Architectural coating compositions for high humidity environments

Abstract

Disclosed herein is an aqueous architectural composition comprising an optional opacifying pigment, and a copolymer polymerized from a plurality of monomers, wherein a combined weighted solubility is less than 8.0 g / 1, preferably less than about 6.0 g / 1 or less than 4.5 g / 1, and higher than 0.5 g / 1 and wherein monomers' solubility is measured at a temperature from 20°C to 30°C, and wherein the weighted solubility excludes the solubilities of functional monomers and wherein the monomers are polymerized with substantially all polymerizable surfactants and preferably all polymerizable surfactants.

Description

Docket No. BJM-135.PCTARCHITECTURAL COATING COMPOSITIONS FORHIGH HUMIDITY ENVIRONMENTSFIELD OF THE Mi MON[0001 J The present invention is directed to architectural coating compositions, such as paints and stains, used in high humidity environments, such as baths and spas. The present invention is further directed to architectural compositions that comprise a hydrophobic latex resin polymerized mostly with reactive surfactants or with all reactive surfactants.BACKGROUND OF THE INVENTION

[0002] Coatings used in bath and spa applications and in tropical environs encounter problems, including water marks, streaks caused by surfactant leaching, and other defacement issues, due to high humidity. One conventional solution is to use paints that produce paint films with high water vapor transmission to promote the paint films’ ability to resist water vapor condensation by absorbing the water vapor. Water vapor absorption by the paint film, however, can cause loss of adhesion to the walls and delamination. This conventional approach minimized water dripping and streaking down walls. However, surfactant leaching remained a problem.

[0003] Commonly owned U.S. patent No. 8,907,002 to Chen el al discloses a vinyl acrylic copolymer latex resin for high humidity environments, such as baths and spas. The paint film formed from this copolymer latex resin has a water contact angle (WCA) of higher than 60° and a water vapor transmissivity or permeability (WVT) of 0.5 mg / cm2smm,,24hr or greater (mg of w'ater vapor per area of paint film in cm2x thickness of paint film in mm in a 24 hour period). The Chen patent, which is incorporated herein in its entirety', teaches that high WVT values is desirable and can resist water vapor condensation. The Chen patent does not discuss surfactant leaching, which measures leaching caused by liquid water, on its paint films. The present inventors do not believe that transmissivity or permeability of water vapor through paint films affect the compatibility of paint films in high humidity environments.Transmissivity or permeability is directly related to the porosity of the paint films or the empty interstitial spaces among the latex particles in the paint films. It is known that larger latex particle sizes would produce paint films with larger pore spaces and thereby higher transmissivity or permeability. It is also known that paint films with higher porosity' are susceptible to staining for the same reason.Docket No. BJM-135.PCT

[0094] There remains a need for paint compositions that can resist both water dripping and streaking and surfactant leaching in high humidity environments, such as baths and spas or tropical humid environments.SUMMARY OF THE INVENTION

[0005] Hence, an embodiment of the invention is directed to an aqueous architectural composition comprising an optional opacifying pigment, and a copolymer polymerized from a plurality of monomers, wherein a combined weighted solubility is less than 8.0 g / 1, preferably less than about 6.0 g / 1 or less than 4.5 g / 1, and higher than 0,5 g / 1 and wherein monomers’ solubility is measured at a temperature from 20°C to 30°C, and wherein the weighted solubility excludes the solubilities of functional monomers, and wherein the monomers are polymerized with substantially all polymerizable surfactants.

[0806] In one embodiment, the polymerizable surfactant makes up 90 wt.% or more of all surfactants, preferably the polymerizable surfactant makes up 95 wt.% or more of all surfactants.

[0007] Preferably, the monomers are polymerized with only polymerizable surfactants.

[0008] Preferably, the polymerizable surfactant ranges from about 0.4 wt.% to about 3.0 wt.% of total monomer solids, more preferably from about 0.4 wt.% to about 2.75 wt.% of total monomer solids, and more preferably from about 0.5 wt.% to about 2.5 wt.% of total monomer solids.

[0009] In one embodiment, a paint film formed from the aqueous architectural composition has a 60° gloss reading between 10 gloss units (GU) and 25 GU, i.e., the paint film may have a matte or eggshell finish. In another embodiment, a paint film formed from the aqueous architectural composition has a 60° gloss reading between 3 GU and 15 GU, or a 85° sheen reading between 3 GU and 25, or both.

[8010] In another embodiment, the plurality of monomers include a styrene monomer and a (meth)acryiate monomer.

[0011] In one embodiment, the functional monomers include cross-linkable monomers, wet adhesion monomers and chain transfer agents.

[0012] In one embodiment, the aqueous architectural composition of claim I further comprising a coalescent aid in the amount less than about 25 ibs. / l 00 gal., and greater than about 5 lbs. / 100 gal., preferably greater than about 10 Ibs. / l OO gal., more preferably greater about 15 Ibs. / lOO gal., more preferably greater than about 20 lbs, / 100 gal.Docket No. BJM-135.PCTBRIEF DESCRIPTION OF THE DRAWINGS

[0013] In the accompanying drawing, which forms a part of the specification and is to be read in conjunction therewith:

[0014] Figure 1 shows genera! formulas of examples of reactive surfactants.DETAILED DESCRIPT10N OF THE ^REFERRED EMBODIMENTS

[0015] The above identified problems are resolved by the inventive paint compositions that utilizes hydrophobic latex polymers comprising substantially styrene and (meth)acrylate monomers that are polymerized with essentially all or preferably all polymerizable or reactive surfactants. The inventive paint compositions produce paint films that resist surfactant leaching caused by water and water vapor, and water dripping and streaking. The inventive paint compositions preferably have lower sheen, such as a matte or eggshell finish, to maintain a desirable ambiance with lower light luminescence for baths and spas.

[0016] The hydrophobicity or hydrophilicity of a surface to a liquid can be determined by water contact angle (WCA) formed by a droplet of that liquid on said surface. A full discussion of the hydrophobicity of a solid surface relative to a liquid is provided below. The WCA is reported in degrees (°) and is a qualitative measurement but not a quantitative measurement. The surface energy or surface free energy (SFE) (mN / m) can be calculated based on WCA, as discussed below. Higher SFE values indicate good wettability and hydrophilicity; WCA higher than 90° typically indicates hydrophobicity.

[0017] The scientific literature has reported a Hansch parameter as a quantitative measurement of hydrophobicity in “Correlation of Biological Activity of Phenoxy acetic Acids with Hammet Substituent Constants and Partition Coefficients,” by C. Hansch, P. Maloney, T. Fujita and R. Muir in Nature, Vol. 194, pp. 178-180 (1962). The Hansch paper reported the research relating to the biological activities in the pharmaceutical field.

[0018] The Hansch paper correlates the biological activities of certain acids with the Hammett substituent, constants. It is related to the fields of medicinal chemistry or pharmaceuticals. In a paper by S. Chandrasekhar, “A Kinetic Basis for the Hansch Equation” (https: / / dl.icdst.org / pdfs / files2 / 5dfd4742ef0d7afafb93139839b55261.pdQ the author states that “the Hansch equation leads to a parabolic relationship between drug activity and hydrophobicity.” This paper also explains that “the Hansch equation defines the fundamental basis of QSAR [quantitative structure activity' relationship], and mathematically relates drugs activity to hydrophobicity.” The Hansch parameter is not solely related to the hydrophobicityDocket _Ncu BJM-135.PCT of monomer, but relates drug efficacy to hydrophobicity. Chandrasekhar also describes a hydrophobicity parameter that is related to “oil / water” partition coefficients.

[0019] The Hansch parameter has been used in connection with hydrophobicity of monomers used in architectural coatings in the patent literature. US 2014 / 0170428 Al, which cited to the 1962 Hansch paper, uses the Hansch parameter in connection with the hydrophobicity of polymer / paint films without discussing the drug activities. WO 2017 / 172520 also calculates the Hansch parameter in reference to an “octanol-water partition coefficient,” in an apparent disagreement with the Chandrasekhar paper. Hansch parameters are reported only for a few common monomers and the reported values can be different for the same monomer. However, these discussion s have not accounted for the connection of the Hansch parameter to drug efficacy.

[0020] The present invention relates in part to the hydrophobicity of paint films, which relates to the relationship between paint films formed from aqueous latex polymeric particles, when dried. One parameter that is directly related to a polymer film and water is the solubility of the monomers present in the film and water. Solubility values of monomers in water are commonly available in chemical encyclopedias, such as the Polymer Handbook 4!hEd.. J. Brandrup et al. (editors), Wiley-InterScience Publication (1999), and scientific websites such as PubChem from the U.S. National Institute of Health’s National Library of Medicine (pubchem.ncbi.nlm.nih.gov / ) and the European Union’s European Chemical Agency (echa.europa.eu / ).

[0021] Solubility values are quantifiable and can be used to accurately estimate or define solubility values of copolymers by taking into account the solubility of each monomer and its weight percentage in the copolymers to arrive at a weighted solubility of the copolymers. Low solubility correlates to hydrophobicity and high solubility correlates to hydrophilicity. This weighted solubility represents an aggregate hydrophobicity / hydrophilicity of copolymers.[9022[ The copolymers that make up the latex resin in the present invention are polymerized from various (meth)acrylate monomers, vinyl monomers, and styrene, among others, as discussed below. These monomers contribute to the properties of the paint film, formed when the copolymer solutions or paint compositions dried. Smaller amounts of monomers known as functional monomers, less than about 2.0 wt.% or preferably less than about 1.5 wt.% of all monomers (solid), are added to the monomer mixture to perform specific functions, such as cross-linkable monomers, chain transfer agents (CTA) and wet adhesion monomersDocket No. BJM-135.PCT(WAM). Cross-linkable monomers, such as diacetone acrylamide (DAAM) and acetoacetoxy ethyl methacrylate (AAEM), add to the hardness of the paint film far more than their own Tg contribution based on their wt.% to the copolymer’s Tg. CTAs end the polymeric chain during polymerization and reduce the molecular weight of the copolymer. CTAs’ effects on the copolymer’s molecular weight is far more than their own molecular weight. WAMs are added to promote adhesion of the paint film the substrate in humid and wet conditions. WAMs’ contributions to Tg, molecular weight and solubility are not as important and WAMs’ inclusions can skew these properties. As used herein, functional monomers’ contributions to Tg, molecular weight and solubility of the inventive copolymers used in the inventive coatings are omited. Acid monomers, such as AA, MAA, itaconic acid monomers, are used to assist the polymerization process and are not considered as functional monomers.

[9023] In accordance with one aspect of the present invention, the hydrophobicity of the film-forming copolymers is determined by a weighted solubility of the monomers making up the copolymers. Preferably, the weighted solubility without functional monomers is less than 8.0 g / 1, preferably less than about 6.0 g / 1 or less than 4.5 g / 1, and higher than 0.5 g / 1 at a temperature from 20°C to 30°C. Hydrophilic monomers may be used along with hydrophobic monomers, as long as the weighted solubility is within these ranges. Any monomers can be used in combination with each other in the present invention, so long as the weighted solubility is within the ranges stated herein.

[0024] The copolymers that make up the latex resin in the present invention are preferably polymerized with substantially all reactive or polymerizable surfactants and preferably only with reactive or polymerizable surfactants. “Substantially all” means that at least 90 wt.% or preferably at least 95 wt.% of the surfactants used in the polymerization are reactive or polymerizable surfactants. The co-inventors have found that polymerization of hydrophobic monomers meeting the preferred weighted solubility range with non-polymerizable or non- reactive surfactants, however, does not produce paint films that resist high humidity environments, as shown below.

[0025] An exemplary inventive latex copolymer is shown below. inventiveExample 1.Docket No. BJM-135.PCTDocket No. BJM-135.PCT~ The reactive surfactant(s) used in this non-limiting exampie can be polymerizable ether sulfate surfactants, which are commercially available as Adeka SR-1025 or DKS Hitanol SR 1025, which are anionic ether sulfate surfactants at 25% solid, Other suitable reactive surfactants (also known as polymerizable surfactants) are described below'.- The wet adhesion monomer is N-(2~methacryktyloxyethyl)-ethylene urea (www.chemicalbook.com / msds / 2-2-oxo-l-imidazolidinyl-ethyl-methacrylate.htm). [00261 The weighted solubility of the copolymer in Example 1 without functional monomers is calculated as follows:It is noted that this solubility value of 2EIIA used herein is published by the ECHA Chemical Database (Europe) and by the Technical Data Sheet of 2EHA from Synthomer PLC. On the other hand, NHI’s PubChem website reports the solubility of 2EHA in water as 0.1 g / l. The values of 2EHA’s solubility don’t affect very much the overall weighted solubility, and both values are acceptable.

[0027] The total weighted solubility is 2.94 g / l and total solid reactive surfactant is 15.465 grams (61.86 grams at 25% solid), which is 0.85 wt.% of total monomer solids (15.465 + (1,804.8+15,465)). Preferably, the solid reactive surfactant ranges from about 0.4 wt.% to about 3.0 wt.% of total monomer solids, more preferably from about 0.4 wt.% to about 2.75 wt.% of total monomer solids, and more preferably from about 0.5 wt.% to about 2.5 wt.% of total monomer solids.

[6028] The copolymer from Example 1 is used to make an inventive matte paint (Paint Example 2) and an inventive eggshell paint (Paint Example 3), as shown belov,'.

[0029] Paint .Esamgle 2. Inventive Matte PaintDocket No. BJM-135.PCT

[0030] Paint Inventive Eggshell PaintDocket No. BJM-135.PCT10031] A comparative latex resin and a comparative paint were also prepared, as shown below.Comparative Resin Example 1.Docket No. BJM-135.PCT

[0032] The Comparative resin was polymerized with essentially no reactive surfactant, except for a very small amount of SVS, which is also classified as a monomer. The weighted solubility for Comparative Example 1 is shown below.

[0033] The comparative bath and spa paint prepared with the comparative latex resin is shown below.Docket No. BJM-135.PCT

[0034] Paint Examples 2 and 3 were tested in along with the Comparative bath and spa paint. The results are summarized in the following table.Docket No. BJM-135.PCTWCA: water contact angle0- higher than 90° indicates hydrophobic surface.SFE: surface free energy, which comprises a disperse fraction and a polar fraction, and can be calculated from the WCA.Surfactant Leaching; 20 (highest score) = no water or leachate marks.Bath test: 1-day and 10-day exposure: 10 (highest score) = no change

[0035] The inventive Paint Examples 1 and 2 included a higher VOC coalescent aid Haltanol, while the Comparative paint is a production paint that utilizes a lower VOC coalescent aid Optifilm 400. This causes the VOC of the inventive prototype Paint Examples to have higher VOC depending on the amount of Haltanol used. It is expected that a tower VOC coalescent aid is used in non-prototype inventive paints.

[0036] The gloss and sheen measurements, described further below, confirmed that inventive Paint Example I has a mate finish, as well as the Conventional Paint Example 1, and that inventive Paint Example 2 has an eggshell finish. Preferably, the inventive paints have a 60° gloss between 2 and 25 gloss units (GU) indicating the preferred mate and eggshell finishes.

[0037] The water contact angle (WCA) measurements showed that all three paint films are hydrophobic. Both inventive Paint Examples 2 and 3 are more hydrophobic than the Comparative Paint Example and the matte Paint Example 2 is considerably more hydrophobic than the Comparative Paint Sample.Docket No. BJM-135.PCT

[0038] The surface energy or surface free energy (SFE) values are higher for the Comparative Paint than for both inventive Paints, indicating that the Comparative Paint is more wettable and therefore less hydrophobic than the inventive Paints. SFE values were obtained with a mobile surface analyzer (MSA) by KRUSS Scientific by measuring the contact angle of a polar liquid (water) and a non-polar liquid (diiodomethane or methylene iodide (CH2I2)) on the dry paint film. The SFE value (mN / m) = disperse value + polar value.

[0039] The WCA and SFE tests showed that the inventive Paint Examples 2 and 3 are more hydrophobic than the Comparative Paint Example.

[0040] The surfactant leaching test, which is described fully below, is a visual test where observers rate the painted surface after water droplets are deposited and after water is sprayed on to the painted surface on a scale from 1. to 5 with 5 means no leaching. The score is a summation of the w'ater drops and sprays test after 1 day and 7 days. The highest score is 20, which represents no surfactant leaching. The surfactant leaching scores for the inventive Paint Examples 2 and 3 are 17.5 and 18.0, respectively, which are close to no surfactant leaching. Comparative Paint Example 1 has a 7.5 score, which signifies significant surfactant leaching.

[0041] The bath test is another visual test where observers rate the painted surface after it is exposed to water vapor on a scale from 1 to 10 with 10 means no change in the appearance of the painted surface. For this test, a painted surface of 6-inch by 6-inch was dried for 24 hours, and was then positioned at a distance of 1 -inch with the painted surface facing a water bath at 60°C. The painted surface was removed after 15 minutes and the painted surface was allowed to dry for 1 day and 7 days. The number of water streaks, if observed, are counted.

[0042] The inventive Paint Examples 2 and 3 have significantly higher water bath scores, 6 and 7, after 1 day than the Comparative Paint Example 1’s score of 2. The inventive Paint Examples also have better water bath scores after 7 days, 7 and 8, than the Comparative Paint Example’s score of 4. The inventive Paint Example 3 has 3 water streaks after 1 day, and no water streak after 7 days. The inventive Paint Example 2 has no water streak after 1 day and 7 days. The present inventors also noted that higher amounts of coalescent aids (Paint Example 2 vs. Paint Example 3) could have reduced the water streaking at I -day interval. Preferably, a low-VOC coalescent aid is utilized in the present invention in the amount of greater than about 5 Ibs. / lOO gal., preferably greater than about 10 Ibs. / lOO gal., more preferably greater about 15 ibs. / lOO gal. or greater than 20 lbs. / 100 gal., and less than about 25 lbs. / l 00 gal.Docket No. BJM-135.PCT

[0043] The results show that the inventive paint compositions with latex resins copolymerized from monomers that meet the weighted solubility in water, discussed herein, and with substantially all and preferably all reactive / poiymerizable surfactant(s) form paint films suitable for high humidity conditions, such as baths and spas as well as tropical environments. The inventive paint films resist both surfactant leaching and water stai n ing / streaking,

[0044] Without being bound to any particular theory', the present inventors believe that there appear to be two methods / mecbanisms to approach formulating paints for high humidity areas. The first is to have a paint system with a latex resin of a certain hydrophilicity, e.g., having a relatively high hydrophilic monomer such as vinyl acetate along with some (meth)acrylate monomers so that water doesn’t sit on the paint film surface and run down or get trapped inside and make the film more water sensitive. In this first system, there is little surfactant leaching (streaking surfactant trails) on the walls during the bath test (water vapor test). However, this tends to give poor surfactant leaching results when liquid water is put directly on the film, not just water vapor. Such paint system is described in U.S. patent No. 8,907,002.

[0045] On the other hand, in the inventive paint system the latex resin is highly hydrophobic or super hydrophobic, e.g., having a relatively high level of styrene and other hydrophobic (meth)acrylate monomers, water repels so much that it does not sit on the film. In this inventive paint system, its paint films repel the water in both the vapor bath test and liquid water the surfactant leaching test. This Inventive highly hydrophobic system is advantageous over the paint system described in US 8,907,002 in that it resist surfactant leaching in both high water vapor environment as well as liquid water environment.

[6046] Polymer compositions that have latex resins He in between that super hydrophobic / super hydrophilic systems do not seem to have these benefits.

[0047] Suitable film-forming monomers and paint additives are described in commonly owned U.S. patent Nos. 1 1 ,345,769, which is incorporated herein by reference in its entirety. Those of ordinary skill in the art can select a set of monomers, so long as the set meets the weighted solubility' in water discussed herein.

[0048] lls drophuhic Surfaces. The hydrophobicity (or wettability) of a solid surface such as a paint film depends on the forces of interaction between water, the surface and the surrounding air. See J. C. Berg, "Wetability'”, Marcel Dekker, New York, 1993 and A. W. Adamson, "Physical Chemistry of Surfaces”, Wiley. The forces of interaction between waterDocket No. BJM-135.PCT and air are surface tension, ytv. Similarly, a surface energy, ysv, is defined as the forces between a solid and the surrounding air and interface tension, VLS, is defined as the forces between the solid and water. For a drop of liquid in equilibrium on a surface, Young's equation stipulates that ysv - YLS~ ?LV COS 0, where 9 is the contact angle of the drop of water or WCA in relation to the surface. Young's equation also shows that, if the surface tension of the liquid is lower than the surface energy, the contact angle is zero and water, wets the surface. Additionally, the water may partially wet the surface (contact angle greater than 0°). If the contact angle is between 0° and 90° the surface is considered hydrophilic; and if the contact angle is greater than 90° the surface is considered hydrophobic. And in certain instances, super-hydrophobic materials, such as lotus leaves, have been noted as having a static water contact angle above 150°. In particular, the static contact angle of a substrate can be measured using a contact angle goniometer and can be measured by methods known to those skilled in the art including the sessile drop method (static and dynamic), Wihelmy method (dynamic and single-fiber), and powder contact angle method.[0(149] The surface energy of a solid, which is the excess energy available at the surface of a solid as compared to its bulk, is determinative of the solid’s hydrophilic or hydrophobic state. Matter seeks to be in a low energy state and chemical bonds reduce energy. Thus, surfaces that have high surface energies tend to be hydrophilic since those surfaces will initiate binding with the hydrogen molecules within water. Hydrophobic materials have lower surface energies and are unable to form hydrogen bonds with water, and water repels the hydrophobe in favor of binding with itself. Young’s equation illustrates this point.

[0050] The surface energy of a solid surface depends on several factors (J. P. Renaud and P. Dinichert, 1956, "Etats de surface et etalement des huiles d'horlogerie", Bulletin SSC III page 681): the chemical composition and crystallographic structure of the solid, and in particular of its surface, the geometric characteristics of the surface and its roughness (and therefore the defects and / or the state of polishing), and the presence of molecules physically adsorbed or chemically bonded to the surface, which can easily mask the solid and significantly modify its surface energy .[0051 j The Owens Wendt Theory, also known as the harmonic mean method, can be used to measure the surface energy of a solid. Owens, D. K.; Wendt, R. G. "Estimation of the surface force energy of polymers", J. Appl. Polym. Sci. 1969, 51, 1741-1747. This theory posits that the surface energy of the surface is the sum of its polar and dispersive components, The polar component accounts for dipole-dipole, dipole-induced, hydrogen bonding and other siteDocket No. BJM-135.PCT specific interactions between a solid and liquid. The dispersive component accounts for surface interactions from Van der Waals and other non-site specific interactions between a solid and liquid. The model is based on two fundamental equations which describe the surface interactions between solids and liquids: Good's Equation (osr =CS+GL-2 (OLDCSD)1 / 2- 2(OLPOSP)1 / 2) and Young's Equation (OS=OSL+OL COS 6). The dispersive component of the surface tension of the wetting liquid is GLD; the polar component of the surface tension of the wetting liquid is <JLP; the dispersive component of the surface energy of the solid is <~$B: and the polar component of the surface energy of the solid is osp. Combining Good's and Young's equation produces the following equation: GL (COS 6 t- 1) / 2+ (asD) "2. The equation has the linear form of y=mx+b, whereby y ~ GL (COS 0 + l) / 2 (OLD)

[0052] The polar and dispersive components of the wetting liquids are known in the literature. A series of replicate contact angles are measured for each of at least two wetting liquids that include, but are not limited to, diiodomethane, benzyl alcohol, ethylene glycol, formamide and water. The y's are plotted as a function of x’s and the polar component of the surface energy. osp, is equivalent to the square root of the slope, m, and the dispersive component of the surface energy, <~sD, is equivalent to the square root of the y-intercept, b.

[0053] Additionally, the surface energy of a solid may be measured using contact angle hysteresis. To make this measurement a pipete injects a liquid onto a solid, and the liquid forms a contact angle. The pipette then injects more liquid, the droplet will increase in volume and its contact angle will increase, but its three phase boundary will remain stationary until it suddenly advances outward. The contact angle the droplet had immediately before advancing outward is termed the advancing contact angle. The receding contact angle is now measured by pumping the liqu id back out of the droplet. The droplet will decrease in volume, the contact angle will decrease, but its three phase boundary will remain stationary until it suddenly recedes inward. The contact angle the droplet had immediately before receding inward is termed the receding contact angle. The difference between advancing and receding contact angles is termed contact angle hysteresis and can be used to characterize surface heterogeneity', roughness, mobility, and wettability. Preferably the contact angle hysteresis should be relatively small for a hydrophobic surface; and for a super hydrophobic surface should be less than 5°.

[0054] A hydrophobic surface may be determined by at least one, or more, of the following measures: static water contact angle, surface energy, and contact angle hysteresis. If theDocket No. BJM-135.PCT static water contact angle is used, the static water contact angle should be greater than 90°, preferably it is greater than 120°, and most preferably greater than 150°. If surface energy is used, the surface energy should be less than 40 mJ / m2, more preferably fess than 20 mJ / m2, and most preferably less than 10 mJ / m2. The surface energies may be further evaluated on their dispersive and polar energy components. In particular, the polar energy component of the surface energy may be less than about 5%, less than about 2.5%, less than about 1%, preferably less than 0.4%, and most preferably less than 0.1%. For example, in the instance where the surface energy is less than 40 mJ / m2, preferably the dispersive energy component is less than 40 mJ / m2and the polar energy component is less than 2.0 mJ / m2. Similarly, where the surface energy is less than 20 mJ / m2, preferably the dispersive energy component is less than 20 mJ / m2and the polar energy component is less than 1 mJ / m2. Properties of Polymers by D. W. Van Krevelen (Elsevier 1990) disclose various polymers, their surface energies, and the dispersive and polar components of their surface energies and are hereby incorporated in its entirety by reference. Also, where the surface energy is less than 10 mJ / m2. preferably the dispersive energy component is less than 10 m.T / m2and the polar energy component is less than 0.5 mJ7m2. Where the measure is contact angle hysteresis, the measurement should be less than about 40°, more preferably less than about 20°, most preferably less than about 10°.

[0055] Surfactant Leaching Experiment. This test determines whether surfactants or other water-soluble materials can leach from a paint film to cause a blotchy appearance or tan or brown spots to appear on the paint film when certain environmental conditions exist. Surfactant leaching is a test for probing the extent of exterior water spotting on a coating. The test method for surfactant leaching involved forming 3 -mil draw' down panels of each coating composition. These panels were then allowed to dry in air at about 72°F and 50% RH for about 24 hours. Each panel was then held so that the coating on the substrate was oriented vertically, at which point 3-5 drops of water were applied over the coated area. Additionally, water is also sprayed on the panel. Without changing the orientation of the panels, the coatings were allowed to dry for 1 day and 7 days. The presence or absence of visible staining on each panel was noted and rated from 1 to 5, with 1 representing the most visible stain and with 5 representing no visible stain, for drops and sprays at 1 day and at 7 days. The maximum rating is 20.[ 9056 J The reactive or polymerizable surfactant will be copolymerized with other monomers and incorporated into the polymer of the invention.Docket No. BJM-135.PCTSuitable reactive or polymerizable surfactants include, but are not limited to, ammonium polyoxyethylene- 1- (allyloxymethyl) -alkyl ether sulfate, ether sulfate, ammonium polyoxyethylene nonylpropenylphenyl ether sulfate, polyoxyethylene nonylpropenylphenyl ether, ammonium polyacrylate, styrene-maleic acid copolymer ammonium, polyoxyethylene alkyl ether, polyoxyethylene styrenated phenyl ether, polyoxyethylene polyoxypropylene glycol, polyoxyalkyiene decyl ether, polyoxyethylene tridecyl ether, alkyl benzene sulfonate, dioctyl sulfosuccinate, sodium lauryl sulfate, polyoxyethylene alkyl ether phosphoric ester, polyoxyethylene styrenated phenyl ether phosphoric, ester, polyoxyethylene styrenated phenyl ether sulfate, or polyoxyethylene alkyl ether sulfate. Other suitable examples of the reactive surfactant monomer include, but are not limited to, compounds containing a polymeric unit based on ethyleneoxide and a polymeric unit based on butyleneoxide and containing, at a terminal, an alkenyl group having a terminal double bond and --SO3NH4 (for example, products by the names of “LATEMUL PD-104” and “LATEMUL PD-105” manufactured by Kao Corporation).

[0057] Reactive surfactants possessing, for example, isopropenylphenyl or allyl groups are also suitable. Examples include reactive surfactants sold by PPG Industries, Inc., as MAZON® SAM 181, 183, 184, 211 surfactants which are anionic sulfates or sulfonates and MAZON® SAM 185-187 surfactants which are nonionic surfactants. Other reactive surfactants include the macro monomers sold by Daiichi Kogyo Seiyaku under the names NIOGEN RN, AQUARON or HITENOL BC and KH surfactants. These include polyoxyethylene alkyl phenyl ether compounds of the general formulas shown in Figure 1 .

[0058] In these Formulas, R is nonyl or octyl, and n and m are preferably integers of from 10 to 50 and 10 to 40, respectively. More preferably, n ranges from 10 to 20, and rn from 10 to 20. HITENOL RN, HITENOL KH-0, HITENOL BC10, HITENOL BC20, HITENOL, HS-20 and HITENOL A- 10 products are particularly preferred reactive surfactants. Other such reactive surfactants include the sodium alkyl allyl sulfosuccinate sold by Henkel, under the trade name TREM LF40.

[0059] Gloss and Fi a ish of Paint Films. The gloss or the gloss finish of a dried paint surface indicates the level of shinmess or glass-likeness of the surface. The level of gloss ranges from flat / matte to high gloss. The gloss of a surface can be described as the reflection of light from the surface that is independent of color. To measure gloss, a single beam of light is deflected off the surface at a particular angle into a receptor, and discussed inDocket No. BJM-135.PCT htp: / / www.paintiiifo.com / mpi / approved / sheen.shtmi, which is incorporated herein by reference in its entirety. The receptor gauges the intensity of that light in gloss units. The equipment is standardized with specially produced, polished, glass or ceramic tiles. ASTM method D 523 provides the procedures for performing this gioss test.[00601 ASTM method D 523 uses 60° angle for comparing surface glosses and to determine whether other angles such as 20° and 85°are warranted. The 20° angle is used when the surface sample has a 60° gioss value greater than 70 gioss units, and the 85° is used if the 60° gloss value is less than 30 gioss units, he angle is measured from a vertical axis, e.g., a 60° angle is measured from the vertical line or the Ocline, and the 60° angle is 30° above the surface being tested.

[0061] Commonly, the term sheen is used to describe the low angle gloss, e.g., 85° from vertical or 5° above the surface to be measured. The 85° angle is preferred in measuring low gloss coatings, and is generally a more accurate indicator of the transition between flat and eggshell. Steep angles, such as 20°, are more often used with a high gloss surface such as automotive coatings.[01)62] The Master Paint Institute (MP1) categorizes the gloss finishes of paints as follows:TABLE. The Reflectivity of Paints with Different Gloss at Different AnglesHigher gloss values indicate shinier surfaces.

[0663] For the present invention, the inventive paints preferably have satin or eggshell finishes or have 60° gloss readings between 2 GU and 25 GU, or 2-10 GU for matte and 10- 25 GU for eggshell at 60° gloss readings.

[0064] Tg, glass transition temperature, can be readily calculated by Fox’s equation, as discussed below, which aggregates the weight fraction of each monomer and the Tg of aDocket No. BJM- 135.PCT mono-polymer made entirely from that monomer. As calculated, Tg generally does not include the hardness caused by the cross-linking of the polymer chains. The crosslinking monomer(s) when added to the monomer mixture typically is used in relatively low amounts, e.g., less than about 10 wt.%. The calculated Tg preferably includes the film forming monomers. The cross-linking monomers, and any functional monomer whose contribution to the polymer is less than about 2.0 wt.% or preferably less than about 1.5 wt.% and whose Tg is not widely available, such as wet adhesion monomers are omitted from the Tg calculations. Chain transfer agent is also omitted from the Tg calculations.

[0065] The aggregated Tg of a co-poiymer calculated by Fox’s equation includes the individual Tg of various monomers being co-poIymerized, as follows: l / Tgagg=Wfi / TgiHAVt2 / Tg2-!-WVrgx, where Tgaggis the aggregated Tg of the co-polymer Wfxis the weight fraction of each monomer x Tgxis the Tg of a polymer made from the single monomer x x is the number of monomers in the co-polymer

[0066] Differential scanning calorimetry (DSC) is a technique commonly used to measure experimentally the response of polymers to heating. DSC can be used to study the melting of a crystalline polymer or the glass transition to measure Tg. DSC can measure the hardness caused by crosslinking of the polymers resulting in higher Tg, as well as the hardness of the un-crosslinked polymers. The DSC set-up generally comprises a measurement chamber housing two pans and a computer to control the heating of the pans. The sample pan contains the material being investigated. A second pan, which can be empty, is used as a reference. The computer is used to monitor the temperature and regulate the rate at w'hich the temperature of the pans changes. A typical heating rate is around 10 °C / min. The rate of temperature change for a given amount of heat will differ between the two pans. This difference depends on the composition of the pan contents as well as physical changes such as phase changes. For the heat flux, the system generally varies the heat provided to one of the pans in order to keep the temperature of both pans the same. The difference in heat output of the two heaters is recorded. If a polymer in its solid state is heated it will at some point reach its Tg. At this point the mechanical properties of the polymer change from those of a britle material to those of an elastic material due to changes in chain mobility. The heat capacity of the polymer is different before and after Tg. The heat capacity Cp of polymers is usually higher above Tg. It is important to note that the transition does not occur suddenly atDocket No. BJM-135.PCT one unique temperature but rather over a range of temperatures. The temperature in the middle of the inclined region is taken as the Tg. The glass transition results in a kink in the heat versus temperature plot due to the change in heat capacity. In a plot of heat flow versus temperature it is a gradual transition that occurs over a range of temperatures. The glass transition temperature is taken to be the middle of the sloped region. See generally polymerscience.physik.hu-berlin.de / docs / manuals / DSC.

[0067] The Tg values by DSC are preferably measured with solid samples of the polymer without any of the crosslinking compounds such as hydrazine or hydrazone in the aqueous phase of the paints or stains that would crosslink with monomers such as DAAM. Hence, the Tg(DSC) reported are the Tg of the un-crosslinked polymers.[0(568] For the present invention, Tg can be calculated by Fox’s equation or measured by DSC.

[0069] While it is apparent that the illustrative embodiments of the invention disclosed herein fulfill the objectives stated above, it is appreciated that numerous modifications and other embodiments may be devised by those skilled in the art. 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 invention.

Claims

Docket No. BJM-135.PCTCLAIMSWe claim :

1. An aqueous architectural composition comprising an optional opacifying pigment, and a copolymer polymerized from a plurality of monomers, wherein a combined weighted solubility is less than 8,0 g / 1, preferably less than about 6.0 g / 1 or less than 4.5 g / 1, and higher than 0.5 g / 1 and wherein monomers’ solubility is measured at a temperature from 20°C to 30°C, and wherein the weighted solubility excludes the solubilities of functional monomers, wherein the monomers are polymerized with substantially all polymerizable surfactants.

2. The aqueous architectural composition of claim 1, wherein the monomers are polymerized with only polymerizable surfactants.

3. The aqueous architectural composition of claim 1 , wherein the polymerizable surfactant ranges from about 0.4 wt.% to about 3.0 wt.% of total monomer solids, more preferably from about 0.4 wt.% to about 2.75 wt.% of total monomer solids, and more preferably from about 0.5 wt.% to about 2.5 wt.% of total monomer solids.

4. The aqueous architectural composition of claim 1, wherein a paint film formed from the aqueous architectural composition has a 60° gloss reading between 10 gloss units (GU) and 25 GU.

5. The aqueous architectural composition of claim 1 , wherein a paint film formed from the aqueous architectural composition has a 60° gloss reading between 3 gloss units (GU) and 15 GU, or a 85° sheen reading between 3 GU and 25 GU, or both.

6. The aqueous architectural composition of claim 1, wherein the plurality of monomers include a styrene monomer and a (meth)acrylate monomer.Docket No. BJM-135.PCTI. The aqueous architectural composition of claim 1, wherein the polymerizable surfactant comprises an anionic ether sulfate surfactant.

8. The aqueous architectural composition of claim 1, wherein the polymerizable surfactant makes up 90 wt.% or more of all surfactants.

9. The aqueous architectural composition of claim 8, wherein the polymerizable surfactant makes up 95 wt.% or more of all surfactants.

10. The aqueous architectural composition of claim 1 fi-rther comprising a coalescent aid in the amount less than about 25 Ibs. / lOO gal. and greater than about 5 Ibs. / lOO gal., preferably greater than about 10 lbs. / l 00 gal., more preferably greater about 15 IbsJlOO gal., more preferably greater than about 20 Ibs. / lOO gal.I I . The aqueous architectural composition of claim I , wherein the functional monomers include cross-linkable monomers, wet adhesion monomers and chain transfer agents.

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