Freeze-thaw additive composition

Abstract

A freeze-thaw stabilizer additive composition comprising (a) at least one antifreeze agent, (b) at least one emulsifier, and (c) any other desired optional compounds, a process for making the freeze-thaw stabilizer additive composition, a paint formulation made containing the freeze-thaw stabilizer additive composition, and a process for making the paint formulation.

Description

[Technical Field]

[0001] The present invention relates to freeze-thaw stabilizer additive compositions useful in paint formulations. [Background technology]

[0002] Latex paint formulations generally have highly complex compositions and must possess multiple acceptable properties and meet multiple performance standards. Freeze-thaw (FT) stability is one of the key properties that latex paint formulations must exhibit to ensure a quality architectural coating. FT-stable paint formulations can be frozen and thawed while still remaining a smooth, workable material. To achieve a coating formulation with adequate FT properties, FT stabilizer additives are typically added to the coating formulation. Ethylene glycol (EG) and propylene glycol (PG) are the most widely accepted FT stabilizers in the coating industry. EG and PG are readily soluble in water and coating formulations, and these compounds used as stabilizers in coating formulations are effective in keeping coating formulations stable during freeze-thaw cycles at low dosages. However, EG and PG have strong volatility and are considered one of the major sources of volatile organic compounds (VOCs). With increasing pressure from government regulations to protect the environment, reducing the amount of VOCs present in architectural coatings is highly desirable. Additionally, high performance and environmentally friendly FT stabilizers for paint formulations are in high demand by paint customers.

[0003] Tristyrylphenol (TSP) ethoxylate surfactants have gained acceptance in the paint industry as a non-VOC alternative to EG and PG stabilizers. While TSP-type surfactants are currently classified as "non-alkylphenol ethoxylate (non-APE)-based" or "alkylphenol ethoxylate-free" (APE-free) additives, TSP-type surfactants could conceivably be considered APE (alkylphenol ethoxylate) additives by those skilled in the art, since the primary structure of TSP surfactants is an ethoxylate initiated with tristyrylphenol. However, in terms of performance, TSP-type surfactants used as FT additives are considered by the paint industry to have poor performance for use in mid-end paint formulations with high (e.g., >50 percent) pigment volume concentration (PVC) content. At the same time, some paint customers and formulators have complained that TSP-type products are not only more expensive than other stabilizer products, but also that the use of TSP ethoxylates has a negative impact on paint performance, such as performance related to scrub resistance. It is therefore highly desirable to provide an environmentally friendly (non-VOC, non-APE-based) FT stabilizer composition for use in waterborne paint formulations, which has equivalent or increased FT performance when compared to known PG and TSP ethoxylate surfactants; the FT stabilizer composition also provides improvements in other paint properties, such as scrub resistance.

[0004] Previously, attempts have been made to improve the FT performance of paint formulations using various surfactant compositions. For example, U.S. Patent No. 8,993,658 (B2) discloses a surfactant composition and the use of such a surfactant composition for an aqueous composition, and teaches that ArO-[CH2CH-(CH2CH3)]1-10(CH2CHO)5-50H improves the FT stability in the aqueous paint composition. However, the above patent does not provide any other improvements to the aqueous paint composition while simultaneously increasing the FT stability of the aqueous paint composition.

[0005] In addition to improving the FT performance of compositions, attempts have been made to reduce the VOC content in compositions using various ingredients. For example, U.S. Patent No. 8,119,717 B2 discloses a coating composition used for protection or decoration in the construction industry. The coating includes a latex component and an agent that replaces volatile coalescing solvents, and the resulting coating composition has a low VOC content (e.g., a molecular weight [Mw] of 132 grams per mole [g / mol] or greater). The composition includes (1) a C10-Guerbet alcohol alkoxylate used as a low-VOC coalescing agent component, and (2) polyethylene glycol (PEG) or polypropylene glycol (PPG) used as a freeze-thaw additive. However, the coating formulation taught in the patent is complex and requires multiple ingredients to achieve the benefits described for the coating formulation. Summary of the Invention [Problem to be solved by the invention]

[0006] While some paint formulations may contain ingredients that can be used as FT additives, there is a desire in the paint industry to provide a blend of specific surfactants and specific anti-freeze compounds to improve the FT performance of paint formulations.

[0007] The problems of the prior art are solved by the present invention, which relates to an FT stabilizer additive composition useful in paint formulations, wherein the FT stabilizer additive composition comprises a mixture of a specific antifreeze compound and a specific emulsifier. In some embodiments, such a mixture provides a synergistic effect related to viscosity changes in the paint formulation. Surprisingly, a synergistic effect occurs when a predetermined mixture ratio of the specific antifreeze compound and the specific emulsifier is used to improve the FT performance of a paint formulation containing the FT stabilizer additive composition.

[0008] The novel FT stabilizer additive compositions of the present invention exhibit several advantages in various embodiments, including, for example, good FT stabilization effect in paint formulations made from different types of resin systems, while the compositions exhibit the advantages of being non-VOC and non-APE-based. Performance evaluation of the compositions in paint formulations also shows, in some embodiments, improved scrub resistance compared to conventional TSP-type products. Furthermore, the FT additive compositions of the present invention can be easily produced, for example, by a simple mixing step, without relying on conventional complex synthetic routes.

[0009] In one embodiment, the present invention provides an FT stabilizer additive composition comprising, for example, (a) at least one antifreeze compound such as glycerin alkoxylates, pentaerythritol alkoxylates, sorbitol alkoxylates, and the like; (b) at least one emulsifier such as C12-C14 primary or secondary ethoxylates, ethylene oxide (EO) / propylene oxide (PO) block copolymers, castor oil ethoxylates, isooctanol alkoxylates, isodecanol alkoxylates, and the like; and (c) any optional compounds, as desired.

[0010] In another embodiment, the present invention provides a process for making the above-described FT stabilizer additive composition.

[0011] In yet another embodiment, the present invention provides a coating formulation comprising, for example, (A) a resin system, (B) the FT stabilizer additive composition described above, and (C) any desired optional compounds.

[0012] In yet another embodiment, the present invention provides a process for making the above-described paint formulation. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 1 shows the change in viscosity (KU viscosity) of a paint formulation after the formulation was subjected to the FT test and the dosage of the FT additive composition in the formulation (ratio of antifreeze to emulsifier). DETAILED DESCRIPTION OF THE INVENTION

[0014] As used herein, "freeze-thaw stability," with respect to a formulation, means stability after a specified number of cycles of the freeze-thaw process as determined using the freeze-thaw stability test described in GB / T-9168-2008.

[0015] By "anti-freeze compound" herein is meant an additive capable of lowering the freezing point of water.

[0016] In a broad embodiment, the present invention relates to a freeze-thaw (FT) stabilizer additive composition useful in aqueous paint formulations. The FT stabilizer additive composition of the present invention comprises (a) at least one antifreeze compound and (b) at least one alkoxylated emulsifier. Optional compounds can also be added to the freeze-thaw (FT) stabilizer additive composition, as desired.

[0017] The FT additive composition of the present invention can include one or more antifreeze compounds. For example, in one embodiment, the antifreeze compound can include one or more alkoxylated antifreeze compounds having one or more of the following functionality, including all combinations thereof: (1) (≥) two functional groups, such as multi-OH groups, including, for example, alkoxylates initiated with glycerin, pentaerythritol, and sorbitol, and mixtures thereof; (2) derived from starting alkylene oxide compounds, such as ethylene oxide, propylene oxide, butylene oxide, and mixtures thereof; (3) water solubility with a cloud point of greater than (>) 20°C in a 1 wt% aqueous solution; (4) having a Mw of less than (<) 1,000 in one embodiment, less than 700 in another embodiment, and less than 500 in yet another embodiment; (5) a low-VOC or non-VOC compound; and (6) having a boiling point of greater than 250°C in one embodiment, and greater than 287°C in another embodiment.

[0018] In one embodiment, the antifreeze additive compound comprises at least one of glycerin alkoxylate, pentaerythritol alkoxylate, sorbitol alkoxylate, and mixtures thereof. Antifreeze compounds can include commercially available compounds such as, for example, VORANOL™ CP 300, DOWFAX™ DF 121, VORANOL™ RN482 (available from The Dow Chemical Company), Polyol 4640 (available from Perstorp), and mixtures thereof.

[0019] The amount of antifreeze compound used to prepare the compositions of the present invention includes, for example, 1 wt % to 99 wt % in one embodiment, 10 wt % to 90 wt % in another embodiment, and 20 wt % to 80 wt % in yet another embodiment, based on the total weight of the FT additive composition.

[0020] Some of the advantageous properties exhibited by antifreeze compounds include, for example, (1) the compound is a non-VOC compound and (2) the compound is low foaming. For example, one advantage of using an antifreeze additive compound is that the antifreeze additive compound is non-VOC. As used herein, "non-VOC" means that the VOC content of the additive comprises, in one embodiment, 0% to less than 1% by weight, in another embodiment, 0 to 0.05% by weight, and in yet another embodiment, 0% to 0.001% by weight. The VOC characteristics of the antifreeze additive compound are measured by gas chromatography in accordance with GB 18582.

[0021] Another advantage of using the antifreeze additive compounds is that they are low foaming, where "low foaming" means that the additive foaming is zero or at least kept to an insignificant level as determined by visual observation of foaming compared to conventional antifreeze additive compounds.

[0022] The FT additive composition of the present invention can include one or more alkoxylated emulsifiers. For example, in one embodiment, the alkoxylated emulsifier can include one or more alkoxylated emulsifiers prepared by reacting (bi) an initiator and (bii) an alkylene oxide. Initiator component (bi) includes, for example, C4 to C18 linear or branched alcohols, acids, esters, amines, and mixtures thereof. Typical initiators can include C12 to C14 primary and secondary alcohols, castor oil, isooctanol, isodecanol, and mixtures thereof. Typical alkylene oxides, component (bii), can include ethylene oxide, propylene oxide, butylene oxide, and mixtures thereof.

[0023] In another embodiment, the alkoxylated emulsifier comprises derivatives of alkoxylated emulsifiers such as phosphate esters, sulfates, and mixtures thereof.

[0024] In one embodiment, for example and without limitation thereby, the alkoxylated emulsifier useful in the present invention, component (b), is selected from, for example, one or more of the following alkoxylated emulsifiers: (1) having several alkylene oxide units, in one embodiment >1, in another embodiment >3, and in yet another embodiment >5; (2) having a moderate hydrophilic-lipophilic balance (HLB) value, for example, in one embodiment in the range of 8 to 18, in another embodiment in the range of 8 to 15, and in yet another embodiment in the range of 10 to 15; (3) being dispersible or soluble in water; and (4) when using non-APE-based compositions, avoid using alkylphenol groups in the initiator, component (b).

[0025] In one preferred embodiment, the emulsifier comprises a C12-C14 primary or secondary alkoxylate, a castor oil ethoxylate, and an EO / PO block copolymer, and mixtures thereof. The emulsifier also includes commercially available compounds such as, for example, TERGITOL™ 15-S, ECOSURF™ LF, TERGITOL™ L, TERGITOL™ X (available from The Dow Chemical Company), and mixtures thereof.

[0026] The amount of emulsifier used to prepare the FT stabilizer additive composition of the present invention is, for example, 1% by weight to 99% by weight in one embodiment, each based on the total weight of the FT stabilizer additive composition. In another embodiment, it is contained in an amount of 20% by weight to 90% by weight, and in yet another embodiment, it is contained in an amount of 20% by weight to 80% by weight.

[0027] In one preferred embodiment, when a freeze-thaw (FT) stabilizer additive composition is prepared and used in an aqueous paint formulation, the mixing ratio of component (a) to component (b) is, in one embodiment, 9 / 1 to 1 / 9 by weight, in another embodiment, 8 / 2 to 2 / 8 by weight, and in yet another embodiment, 8 / 2 to 4 / 6 by weight. Within the above ranges, the FT stabilizer additive composition provides a synergistic FT stabilizing effect to the aqueous paint formulation in which the additive composition is used.

[0028] As used herein, with respect to a paint formulation, a "synergistic FT stabilization effect" means that the FT stabilizer additive composition does not substantially or significantly affect the viscosity of the paint formulation. As used herein, with respect to a paint formulation, a "significantly affecting viscosity" means that the use of the FT stabilizer additive composition, when added to a paint formulation, does not increase or decrease the viscosity of the paint formulation. Or, at least, any change in the viscosity of the paint formulation due to the use of the FT stabilizer additive composition is kept to a minimum. It has been found that the use of an antifreeze additive compound, component (a), alone in a paint formulation results in a paint formulation having a substantially higher viscosity than the combined antifreeze additive compound, component (a), and emulsifier, component (b). In this case, the antifreeze additive compound used alone provides a paint formulation with a viscosity that prevents the formulation from becoming flowable and easily handled. It has been found that the use of the emulsifier, component (b), alone in a paint formulation results in a paint formulation with a viscosity slightly higher or the same as that of the combined antifreeze additive compound, component (a), and emulsifier, component (b). Thus, the synergistic FT stabilization effect of the FT stabilizer additive composition of the present invention includes maintaining zero or minimal change, either an increase or decrease, in the viscosity of the paint formulation. For example, the change in viscosity of the paint formulation before and after the addition of the FT stabilizer additive composition of the present invention is less than 20% in one embodiment, 0% to 20% in another embodiment, 0% to 10% in yet another embodiment, and 0% to 5% in yet another embodiment. Viscosity characteristics of paint formulations are measured in Krebs Units (KU) using a KU viscometer, such as a Stormer viscometer.

[0029] In addition to the FT additive compound, component (a), and the alkoxylated emulsifier, component (b), described above, the freeze-thaw (FT) stabilizer additive composition of the present invention may also contain other additional optional compounds or additives, which may be added to the composition together with the FT additive compound or emulsifier. The optional additives or agents that can be used to prepare the freeze-thaw (FT) stabilizer additive composition of the present invention may include one or more optional compounds known in the art for their use or function. For example, optional additives, agents, or components useful in making the FT stabilizer additive composition of the present invention may include wetting agents, dispersants, foam control agents, rheology modifiers, biocides, pH neutralizers, water, etc., and mixtures thereof.

[0030] The amount of any compound used to prepare the composition of the present invention includes, for example, 0% to 50% by weight in one embodiment, 0.01% to 30% by weight in another embodiment, and 1% to 10% by weight in yet another embodiment.

[0031] In a general embodiment, the process for making the freeze-thaw (FT) stabilizer additive composition of the present invention comprises the steps of mixing (a) at least one antifreeze additive compound, (b) at least one alkoxylated emulsifier, and (c) any desired optional compounds.

[0032] In a preferred embodiment, the freeze-thaw (FT) stabilizer additive composition of the present invention can be prepared, for example, by the steps of: (i) weighing predetermined amounts of components (a) and (b) and filling the components into a container to form a mixture; and (ii) stirring the mixture in a container under mechanical agitation at a mixing speed of: In one embodiment, for a period of 20 minutes (min) to 2 hours (hr), and in one embodiment, from 200 revolutions per minute (rpm) to 1,000 rpm.

[0033] Once formed, there are several advantageous properties exhibited by various embodiments of the FT additive composition, for example: (1) the FT additive composition can exhibit excellent freeze-thaw stability, (2) the FT additive composition exhibits good scrub resistance, (3) the FT additive composition is non-VOC, (4) the FT additive composition is non-APE-based, and (5) the FT additive composition is widely compatible with a variety of resins.

[0034] For example, one property of the FT additive composition is to provide a paint formulation with freeze-thaw stability of 0.5% to 1.5% by weight in one embodiment, and 0.5% to 1% by weight in another embodiment. The stability of the paint formulation is measured by particle size measurement or visual observation with the naked eye.

[0035] For example, another property of the FT additive composition is to provide a paint with good scrub resistance. Good scrub resistance means that the FT additive compound does not reduce the scrub resistance of the paint film, or at least maintains a minimal reduction in scrub resistance, compared to conventional PG or EG as the FT additive. The scrub resistance may be, for example, 60% to 120% of that with PG as the FT additive in one embodiment, 80% to 120% in another embodiment, and 90% to 110% in yet another embodiment. The scrub resistance property of a paint formulation is measured by the number of cycles a paint film sample goes through before the film sample is scrubbed across the thickness of the film sample, according to the procedure described in ASTM D2486-74A.

[0036] Another advantageous property of the FT additive composition includes, for example, the FT additive composition being a non-VOC composition. By "non-VOC" herein is meant that the FT additive composition has a VOC content of less than 1 wt. % in one embodiment, between 0 wt. % and 0.05 wt. % in another embodiment, and between 0 wt. % and 0.001 wt. % in yet another embodiment. The VOC properties of the FT additive composition are measured by gas chromatography in accordance with GB 18582.

[0037] Further advantageous properties of the FT additive compositions include, for example, FT additive compositions that are non-APE-based compositions. "Non-APE-based" or "APE-free" herein means that the composition has an alkylphenol ethoxylate content of less than 0.1 wt. % in one embodiment, between 0 wt. % and less than 0.1 wt. % in another embodiment, between 0 wt. % and 0.01 wt. % in yet another embodiment, In yet another embodiment, it means that the alkylphenol ethoxylate content of the composition is measured by high performance liquid chromatography (HPLC).

[0038] The FT additive composition also advantageously has broad compatibility with various resins, such as styrene acrylic (SA) resins, pure or all-acrylic (AA) resins, vinyl acrylic (VA) resins, ethylene-vinyl acetate (EVA) binders, and mixtures thereof. "Compatibility" in this specification means that the FT additive composition of the present invention works effectively with the above different types of resins, and is not suitable for other resins, such as VA resins, compared to conventional TSP-type FT additives that can only work with SA resins.

[0039] The components that make up a paint composition or formulation are well known in the art of making paints and typically include a resin polymer and additives such as water, dispersants, wetting agents, defoamers, thickeners, rheology modifiers, pH buffers, pH neutralizers, biocides, pigments, fillers, coalescents, and the like, and mixtures thereof. The FT stabilizer additive composition of the present invention is useful as another additive for paint formulations. In one preferred embodiment, the FT stabilizer additive composition is useful, for example, in an aqueous paint formulation.

[0040] In one general embodiment, the coating formulation comprises, for example, (A) a resin system, (B) the freeze-thaw stabilizer additive composition described above, and (C) any other desired optional additive compounds, as described above. In a preferred embodiment, the resin system of the coating formulation, component (A), for example, comprises at least one binder. The binder is useful for coating film formation with the coating formulation composition. For example, the binder is selected from the group consisting of pure or all-acrylic (AA) polymers, styrene-acrylic (SA) polymers, vinyl-acrylic (VA) polymers, vinyl acetate-acrylic polymers, ethylene-vinyl acetate (EVA) polymers, etc., and mixtures thereof.

[0041] The concentration of the binder in the paint formulation may be, for example, 5% to 60% by weight in one embodiment, 10% to 60% by weight in another embodiment, In yet another embodiment, it is 10% by weight to 40% by weight.

[0042] Because the FT additive composition is a non-VOC composition as described above, advantageously, the paint formulation of the present invention has no volatile organic compounds present in the formulation, or at least trace amounts of VOCs present in the formulation due to unintentional contamination. Generally, the concentration of VOCs in the formulation is, for example, less than 150 grams per liter (g / L) in one embodiment, less than 50 g / L in another embodiment, and less than 5 g / L in yet another embodiment. In other embodiments, the VOC content of the formulation includes, for example, from 0.01 g / L to less than 150 g / L in one embodiment, from 0.01 g / L to less than 50 g / L in another embodiment, and from 0.01 g / L to less than 5 g / L in yet another embodiment.

[0043] Generally, the paint formulation comprises a water-based paint formulation. In one embodiment, the water-based paint formulation comprises an exterior architectural paint. In another embodiment, the water-based paint formulation comprises an interior architectural paint.

[0044] As described above, once the FT stabilizer additive composition of the present invention is made, the FT stabilizer additive composition is added to, for example, a paint formulation to prepare an FT stabilized paint product. In a broad embodiment, the process for making the paint formulation includes, for example, mixing (A) the resin system described above, (B) the freeze-thaw stabilizer additive composition described above, and (C) any desired optional compounds. Conventional mixing methods used in the paint industry are also useful for preparing paint formulations herein, with mixing of the formulation components being carried out, for example, at a temperature of 20 degrees Celsius (°C) to 30°C in one common embodiment.

[0045] Paint formulations containing the FT stabilizer additive composition exhibit several beneficial properties, including, for example: (1) the paint formulation has improved FT stability, (2) the paint formulation has increased scrub resistance, (3) the paint formulation is a non-VOC alternative, and (4) the paint formulation is a non-APE-based alternative.

[0046] For example, one property of a paint formulation includes, for example, that the paint formulation has freeze-thaw stability from -5°C to room temperature (20°C) in one embodiment, from -10°C to room temperature (20°C) in another embodiment, and from -18°C to room temperature (20°C) in yet another embodiment. The stability properties of a paint formulation and its viscosity are measured according to the test procedures set forth in GB / T-9168-2008. In addition to the above tests for measuring stability, the paint formulation can be analyzed by its appearance to the naked eye to observe any particles that may form undesirable clumps, sedimentation, or caking to confirm the stability properties of the paint formulation.

[0047] Another characteristic of a paint formulation includes, for example, a paint formulation having no VOC or low VOC levels, making the formulation an environmentally friendly formulation. For example, the VOC level of a paint formulation, if any, may be: In one embodiment it is <150 g / L, in another embodiment it is <50 g / L, and in yet another embodiment it is <5 g / L. The VOC profile of the paint formulation is measured by gas chromatography according to GB 18582.

[0048] Further properties of the paint formulation include, for example, paint formulations that exhibit increased scrub resistance. For example, scrub resistance may be 60% to 120% of a control sample having PG as an FT additive in one embodiment, 80% to 120% in another embodiment, and 90% to 110% in yet another embodiment. The scrub resistance property of the paint formulation is measured by the number of cycles in which the film is scrubbed according to the procedure set forth in ASTM D2486-74A.

[0049] The FT additive composition is useful, for example, in water-based paint formulations. Advantageously, low-VOC water-based paint formulations are produced using the above-described FT stabilizer, component (a). The low-VOC water-based paints having the described FT stabilizer, component (a), are useful, for example, in exterior architectural paints and / or interior architectural paints. The present invention includes the following aspects. Section 1. 1. A freeze-thaw stabilizer additive composition comprising: (a) at least one antifreeze compound; and (b) at least one emulsifier, wherein the freeze-thaw stabilizer additive composition provides a paint formulation with stability, such that when the viscosity of the paint formulation is measured at 23°C using a Stormer viscometer before and after the freeze-thaw stability test, the paint formulation experiences a change in viscosity of between 0 percent and less than 10 percent after the formulation is subjected to the freeze-thaw stability test described in GB / T-9168-2008. Section 2. Item 1. The composition according to item 1, wherein the antifreeze compound is selected from the group consisting of glycerin alkoxylates, pentaerythritol alkoxylates, sorbitol alkoxylates, and mixtures thereof. Section 3. Item 3. The composition of item 1 or 2, wherein the at least one emulsifier comprises a C12-C14 primary or secondary alkoxylate, a castor oil ethoxylate, an ethylene oxide / propylene oxide copolymer, butylene oxide, or a mixture thereof. Section 4. Item 1. The composition of item 1, wherein the freeze-thaw stabilizer additive composition provides a paint formulation with an appearance that is devoid of particle aggregation, sedimentation, or caking. Section 5. Item 1, wherein the freeze-thaw stabilizer additive composition provides a paint formulation having (i) a VOC level of from 0 weight percent to less than 1 weight percent, and (ii) an APE level of from 0 weight percent to less than 0.1 weight percent. Section 6. Item 1, wherein the freeze-thaw stabilizer additive composition provides a paint formulation with a scrub resistance of 60 percent to 120 percent of that of one containing propylene glycol, as measured according to the procedure set forth in ASTM D2486-74A. Section 7. Item 1. The composition according to item 1, wherein the emulsifier is an alkoxylated emulsifier or a derivative thereof. Section 8. Item 1. The composition according to item 1, wherein the concentration of the antifreeze compound is 1 weight percent to 99 weight percent, and the concentration of the emulsifier is 1 weight percent to 99 weight percent, each based on the total weight of the composition. Section 9. A process for making a freeze-thaw stabilizer additive composition comprising mixing (a) at least one antifreeze compound and (b) at least one emulsifier. Section 10. 1. A freeze-thaw stabilizer additive composition comprising: (a) at least one antifreeze compound selected from the group consisting of glycerin alkoxylates, pentaerythritol alkoxylates, sorbitol alkoxylates, and mixtures thereof; and (b) at least one emulsifier selected from the group consisting of C12-C14 primary or secondary alkoxylates, castor oil ethoxylates, ethylene oxide / propylene oxide copolymers, butylene oxide, or mixtures thereof. Section 11. A coating formulation comprising: (A) a resin system; and (B) the freeze-thaw stabilizer additive composition described in item 1. Section 12. Item 12. The coating formulation of item 11, wherein the resin system, component (A), comprises at least one binder selected from the group consisting of acrylic polymers, styrene-acrylic polymers, vinyl acetate-acrylic polymers, ethylene-vinyl acetate polymers, and mixtures thereof. Section 13. Item 13. The paint formulation of item 12, wherein the binder is present in a concentration of 5 weight percent to 60 weight percent, based on the total weight of the paint formulation. Section 14. Item 12. The paint formulation of item 11, including a water-based paint formulation. Section 15. A process for making a coating formulation comprising: (A) mixing a resin system with (B) the freeze-thaw stabilizer additive composition described in paragraph 1. [Example]

[0050] The following examples are presented to further illustrate the invention but should not be construed as limiting the scope of the claims. All parts and percentages are by weight unless otherwise indicated.

[0051] Various terms and designations used in the following inventive examples (Inv. Ex.) and comparative examples (Comp. Ex.) are explained below. "PVC" stands for pigment volume concentration.

[0052] Table I sets forth the various materials, ingredients, or raw materials used in preparing the FT additive compositions of the present invention. [Table 1]

[0053] Examples 1-6 and Comparative Examples A-E - Freeze-Thaw Additives The FT additive composition samples of Inv.Ex.1-6 and Comp.Ex.E were prepared by simply mixing the two components specified in Table II under mechanical agitation. The composition samples are listed in Table II. [Table 2]

[0054] The various materials, ingredients, or raw materials used in preparing paint formulations containing the FT additive compositions of the present invention are set forth in Table III. [Table 3]

[0055] General process for preparing paint formulations The following general process was used to prepare paint formulations containing the FT additive compositions of the present invention (referred to herein as "FT stabilizers").

[0056] Part A: Milling Procedure Step (1): The dispersion plate was attached to the dispersion machine.

[0057] Step (2): Water was added to a 1 liter (L) stainless steel cup.

[0058] Step (3): The thickener and pH buffer were added to the steel cup, and the contents of the steel cup were continuously dispersed at 450 rpm for 10 minutes. The resulting mixture gradually became more viscous.

[0059] Step (4): The dispersant and wetting agent were respectively added to the mixture in the steel cup, and the contents of the steel cup were continuously dispersed for 10 minutes.

[0060] Step (5): As the viscosity of the mixture in the steel cup increased, the dispersion speed was gradually increased to 1,800 rpm while titanium dioxide and filler were added to the mixture in the steel cup.

[0061] Step (6): The mixture obtained from step (5) was continuously dispersed for an additional 30 minutes to ensure uniformity of the final mixture obtained.

[0062] Part B: Let-down Procedure Step (7): The dispersion plate was replaced with a stirrer, and the mixture obtained from step (6) was continuously stirred with the stirrer at 1,800 rpm.

[0063] Step (8): The binder, antifoaming agent, coalescent, and biocide were added to the mixture obtained in step (7). As the viscosity of the mixture decreased, the stirring speed of the stirrer was gradually reduced to 700-800 rpm, and the mixture was then continuously stirred at 700-800 rpm for 10 minutes.

[0064] Step (9): The thickener was added to the mixture from step (8), and as the viscosity of the mixture increased, the stirring speed was increased to 1,800 rpm, and the mixture was continuously stirred for 10 minutes. The viscosity, reported in Krebs Units (KU), of the resulting mixture, which is the paint formulation, was adjusted using the thickener. KU viscosities were adjusted in the range of 95 KU to 100 KU. Viscosity is reported in KU as measured using a conventional Stormer viscometer. As is well known, the Stormer viscometer uses a load-based rotation to determine viscosity.

[0065] Part C: Addition of FT stabilizers Step (10): The paint formulation from step (9) was divided into several parts.

[0066] Step (11): Each part of the paint formulation was continuously stirred at 700-800 rpm, and then the FT stabilizer (according to the specific formulation being tested as listed in Table II) was added to the formulation while continuously stirring the formulation for 10 minutes.

[0067] Step (12): Each paint formulation sample from the formulation of step (11) to be tested was kept in the laboratory on a laboratory countertop at room temperature (approximately 23°C) for at least 24 hours before subjecting the sample to the FT test.

[0068] Examples 7-9 - Paint Formulations Three paint formulations were prepared using the general procedure described above, and the paint formulations were tested and evaluated as described herein below. The three paint formulations are listed in Table IV and include (1) a mid-range architectural paint containing an SA binder (59% PVC), (2) an interior architectural paint containing an AA binder (52% PVC), and (3) a mid-range exterior architectural paint containing an AA binder (55.6% PVC). The PVC used in the formulations ranged from 50% to 70%, and the three formulations covered both interior and exterior architectural paints, using both SA and AA type binders. [Table 4]

[0069] Performance Evaluation Test Freeze-thaw stability test (GB / T-9168-2008) The paint formulation samples were placed in a freezer at a temperature of -5±2°C and frozen for 18 hours. The paint samples were then removed from the freezer and placed at room temperature (approximately 23°C) for 6 hours. The freeze-thaw (FT) process was repeated three times for each paint sample, and the appearance of the formulation was visually checked for any of the following phenomena: precipitation, gelation, coagulation, or aggregation. If none of the above phenomena were visually observed in the formulation, the formulation was deemed freeze-thaw stable.

[0070] The KU viscosity of the paint formulation was tested before and after the above FT test as an indicator of FT performance. The lower the KU viscosity change, the better the FT performance of the formulation.

[0071] Scrub Resistance Test (ASTM Test Method D 2486-74A) The general procedure for testing the paint formulation samples was as follows: Step (1): A drawdown of paint is made with a 150 micron (μm) film applicator onto a black vinyl scrub chart.

[0072] Step (2): Allow the black vinyl scrub chart to dry in a current temperature room (CTR) for 7 days.

[0073] Step (3): Place the black vinyl scrub chart in a scrubbing machine and test the chart using an abrasive scrubbing media, for example, Type SC-2.

[0074] Step (4): Start the scrub resistance test and record the first cut-through cycle.

[0075] Performance evaluation results Experiment 1 - Paint formulation containing SA binder (59% PVC) (a) Viscosity The total dosage of the freeze-thaw additive samples was kept at 1 wt% in each test. Delta KU, i.e., the KU obtained after the FT test minus the initial KU, is used herein as a measure of the FT performance of the freeze-thaw additive samples. The smaller the delta KU, the better the FT stabilization performance.

[0076] From the test results shown in Table V and Figure 1, it can be seen that the antifreeze compound, CP300, alone (Comp. Ex. A) exhibited poor FT stabilization performance. After three cycles of the FT test, the paint samples exhibited a solidified appearance with no flowability, even under agitation. When the antifreeze compound CP300 was mixed with the emulsifier 15-S-9 (Comp. Ex. 1-4), FT performance was significantly improved, along with better flowability and less aggregate. Compared with the antifreeze compound CP300 alone (Comp. Ex. A) and the emulsifier 15-S-9 alone (Comp. Ex. B), blends of the two components exhibited smaller delta KU. A synergistic effect was observed at CP300 / 15-S-9 mix ratios of 8 / 2 to 4 / 6 by weight. In contrast, in Comp. Ex. E, emulsifier L-64 was mixed with the antifreeze compound CP300, resulting in poor FT performance. [Table 5]

[0077] (b) Scrub resistance Scrub resistance is an indicator of the densification and shatter resistance of the paint layer. As previously mentioned, one drawback of TSP-type products is their adverse effect on scrub resistance properties. In this scrub resistance test, Comp. Ex. D (using 1% PG) was used as a control. As shown in Table VI, when Inv. Ex. 5 (CP-300 / 15-S-9) was used, scrub resistance was maintained at 91.7% of PG performance. In contrast, the scrub resistance of Comp. Ex. B (15-S-9) was maintained at 48.2% of PG performance. Comp. Ex. B, which contains the emulsifier 15-S-9, had a higher delta KU viscosity than Inv. Ex. 1, shown in Table V, and the scrub resistance of Comp. Ex. B was nearly twice as poor as that of Inv. Ex. 1, shown in Table VI. The scrub resistance performance of Comp. Ex. C (FT-100) was 51.9%, which was also poor. [Table 6]

[0078] Experiment 2 - Interior architectural paint containing AA binder (52% PVC) The inventive examples were evaluated in paint formulations containing AA binders. As shown in Table VII, the FT additive compositions (Inv. Ex. 2 and 6) achieved significantly lower delta KU compared to Comp. Ex. B and Comp. Ex. C. At the same time, the scrub resistance performance of the FT additive compositions (Inv. Ex. 2 and 6) was significantly lower. It was better than FT-100 (Comp.Ex.B). [Table 7]

[0079] Experiment 3 - Mid-end exterior architectural coating containing AA binder (55.6% PVC) Tests were conducted on exterior paints containing AA binders, as shown in Table VIII. Similar to the results of the other experiments above, Inv.Ex.2 exhibited good FT performance with a small delta KU. Additionally, the scrub resistance of Inv.Ex.2 was better than both Comp.Ex.B and Comp.Ex.C. [Table 8]

[0080] From the tests performed as described above, several conclusions can be reached, including, for example, the following: (1) the solution of the present invention can be easily obtained by simple mechanical mixing; (2) mixtures of antifreeze compounds and emulsifiers meeting the above-mentioned criteria can achieve effective performance for stabilizing paint formulations during freeze-thaw cycles; (3) synergistic effects can be achieved by using specific mixing ratios for the components of the composition of the present invention; (4) good EH&S profiles can be achieved with non-VOC, non-APEO-based properties; (5) significant improvements in scrub resistance performance can be obtained using the composition of the present invention compared to conventional TSP derivatives; and (6) the solution can be compatible with different binders in water-based architectural paint formulations.

Claims

1. 1. A freeze-thaw stabilizer additive composition comprising: (a) at least one antifreeze compound selected from the group consisting of glycerin alkoxylates, pentaerythritol alkoxylates, sorbitol alkoxylates, and mixtures thereof; and (b) at least one emulsifier selected from the group consisting of C12-C14 primary or secondary alkoxylates, castor oil ethoxylates, and mixtures thereof, wherein the blend ratio of component (a) to component (b) is 8 / 2 to 4 / 6 by weight; 1. The freeze-thaw stabilizer additive composition of claim 1, wherein the freeze-thaw stabilizer additive composition provides a paint formulation with stability, wherein when the viscosity of the paint formulation is measured at 23°C using a Stormer viscometer before and after the freeze-thaw stability test, the viscosity of the paint formulation changes by 0 percent to less than 10 percent after the formulation is subjected to the freeze-thaw stability test described in GB / T-9168-2008.

2. 10. The composition of claim 1, wherein the freeze-thaw stabilizer additive composition provides a paint formulation with an appearance that is devoid of particle agglomeration, settling, or caking.

3. 10. The composition of claim 1, wherein the freeze-thaw stabilizer additive composition provides a paint formulation with (i) a VOC level of from 0 weight percent to less than 1 weight percent, and (ii) an APE level of from 0 weight percent to less than 0.1 weight percent.

4. 10. The composition of claim 1, wherein the freeze-thaw stabilizer additive composition provides a paint formulation with 60 percent to 120 percent of the scrub resistance of one containing propylene glycol, as measured according to the procedure set forth in ASTM D2486-74A.

5. 10. A process for making the freeze-thaw stabilizer additive composition of claim 1, comprising:

1. A process comprising mixing (a) at least one antifreeze compound selected from the group consisting of glycerin alkoxylates, pentaerythritol alkoxylates, sorbitol alkoxylates, and mixtures thereof, and (b) at least one emulsifier selected from the group consisting of C12-C14 primary or secondary alkoxylates, castor oil ethoxylates, and mixtures thereof, wherein the mixing ratio of component (a) to component (b) is from 8 / 2 to 4 / 6 by weight.

6. 10. A coating formulation comprising: (A) a resin system; and (B) the freeze-thaw stabilizer additive composition of claim 1.

7. 7. The coating formulation of claim 6, wherein the (A) resin system comprises at least one binder selected from the group consisting of acrylic polymers, styrene-acrylic polymers, vinyl acetate-acrylic polymers, ethylene-vinyl acetate polymers, and mixtures thereof.

8. 8. The paint formulation of claim 7, wherein the binder is present in a concentration of 5 to 60 percent by weight, based on the total weight of the paint formulation.

9. 10. The paint formulation of claim 6, comprising a water-based paint formulation.

10. 10. A process for making a coating formulation comprising: mixing (A) a resin system; and (B) the freeze-thaw stabilizer additive composition of claim 1.

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