Aqueous coating compositions, coatings formed therefrom, and articles

Abstract

The present invention relates to a waterborne coating composition, a coating formed therefrom and an article, said waterborne coating composition comprising: a film-forming resin composition, a thickening agent, an environmentally friendly ester-based film-forming coalescent, a filler, optionally an aqueous medium and additional additives; wherein the thickening agent comprises an inorganic thickening agent; wherein the filler comprises diatomaceous earth, said diatomaceous earth being present in an amount of 4-6 wt.%, preferably 4.5-5 wt.%, relative to the total weight of the waterborne coating composition; and wherein the gloss at 60° of a coating formed from the waterborne coating composition differs by no more than 0.4, preferably no more than 0.2, from the gloss at 85°.

Description

TECHNICAL FIELD

[0001] The present application relates to a waterborne coating composition, and also relates to a coating layer formed from the waterborne coating composition, and an article comprising the coating layer. BACKGROUND

[0002] Modern decoration has increasingly high requirements for materials. The appearance of texture paint provides a new direction for indoor wall decoration. Texture paint is actually a pre-artistic coating, also known as texture coating, which can be said to be a replacement product of latex paint. It is a latex paint that can produce texture effects.

[0003] Traditional texture paint can produce various styles of modeling, but the surface feels rough, the style is rough and wild, and for the cloth texture effect, more particles are formed during the construction process and the cloth texture is not natural and continuous, the surface gloss is not uniform, and often needs to be solved by a finish paint to solve the problem of yin and yang surfaces caused by uneven feel and gloss.

[0004] Therefore, it is urgent to develop a new type of coating composition capable of forming cloth texture texture to meet the above application requirements. SUMMARY

[0005] In one aspect, the present application provides a waterborne coating composition comprising:

[0006] a film-forming resin composition, a thickening agent, an environmentally friendly ester film-forming additive, a filler, optionally a waterborne medium, and additional additives;

[0007] wherein the thickening agent comprises an inorganic thickening agent;

[0008] wherein the filler is present in an amount of 4-6% by weight, preferably 4.5-5% by weight, relative to the total weight of the waterborne coating composition; and

[0009] wherein the gloss at 60° of the coating layer formed from the waterborne coating composition differs from the gloss at 85° by no more than 0.4, preferably no more than 0.2.

[0010] In an embodiment of the present application, the thickening agent further comprises a polyurethane thickening agent, preferably a non-ionic polyurethane associative thickening agent.

[0011] In an embodiment of the present application, the film-forming resin composition comprises one or more of an aqueous dispersion of acrylic resin, an aqueous dispersion of polystyrene-acrylic resin, an aqueous dispersion of polyurethane, an aqueous dispersion of polyurethane-acrylic resin, an aqueous dispersion of epoxy resin, an aqueous dispersion of polyester, an aqueous dispersion of polyvinyl acetate, an aqueous dispersion of polysiloxane, preferably one or two of an aqueous dispersion of acrylic resin, an aqueous dispersion of polystyrene-acrylic resin, an aqueous dispersion of polyurethane, and an aqueous dispersion of polyurethane-acrylic resin, more preferably one or two of an aqueous dispersion of acrylic resin, an aqueous dispersion of polystyrene-acrylic resin.

[0012] In a specific embodiment of the present application, the aqueous coating composition comprises:

[0013] 20 to 50 wt% of the aqueous dispersion of acrylic resin, the aqueous dispersion of polystyrene-acrylic resin, or any combination thereof;

[0014] 0.2 to 1.5 wt% of the thickening agent, the thickening agent comprising a combination of inorganic thickening agent, cellulose ether thickening agent, and polyurethane thickening agent.

[0015] 1 to 5 wt% of the environmentally friendly ester coalescent, the environmentally friendly ester coalescent being a non-phthalate environmentally friendly plasticizer, preferably selected from one or more of dipropylene glycol dibenzoate, epoxy acetyl linseed methyl ester, diethylene glycol dibenzoate, diisononyl cyclohexane 1,2-dicarboxylate;

[0016] 5 to 55 wt% of the filler, the filler comprising at least one of heavy calcium powder, silica matting flat powder, talc powder, matting wax paste, or any combination thereof, in addition to the diatomite;

[0017] 0 to 1 wt% of the dispersant, the dispersant being selected from polyacrylate dispersant;

[0018] 0.1 to 0.5 wt% of the wetting agent, the dispersant being selected from silicone wetting agent, acetylenic diol wetting agent, or any combination thereof;

[0019] 0.1 to 0.8 wt% of the defoaming agent, the defoaming agent being selected from organosiloxane defoaming agent, mineral oil defoaming agent, polyether defoaming agent, or any combination thereof;

[0020] 0.5 to 4 wt% of the humectant, the humectant being selected from glycerol, polyethylene glycol, propylene glycol, polyvinyl alcohol, or any combination thereof;

[0021] 0 to 0.4 wt% of the pH adjuster selected from ammonia, organic amines, sodium hydroxide, or any combination thereof;

[0022] 0 to 0.5 wt% of the preservative selected from isothiazolinones, benzimidazoles, Dowicides, or any combination thereof;

[0023] 0 to 0.5 wt% of the bactericide selected from isothiazolinones, iodopropynyl butylcarbamate, carbendazim, diuron, or any combination thereof; and

[0024] 0 to 30 wt% of an aqueous medium.

[0025] In another aspect, the present application provides a coating formed from the above-mentioned aqueous coating composition, the coating having a texture of a cloth grain.

[0026] In another aspect, the present application also provides an article comprising:

[0027] a substrate having at least one major surface; and

[0028] at least one coating layer formed from the aqueous coating composition according to the present application coated directly or indirectly on the major surface.

[0029] The inventors of the present application have surprisingly found that by the specific combination of fillers and thickening agents, the viscosity and consistency of the aqueous coating composition are effectively improved, providing a significant thixotropic effect. By further optimized selection of thickening agents, including inorganic thickening agents and polyurethane-based thickening agents, the apparent particles generated in the making of the cloth grain are significantly reduced. The environmentally friendly ester-based coalescent aids replace the traditional alcohol-ester coalescent aids, assisting film formation, and improving the smoothness and continuity of the cloth grain texture, and also prolonging the open time of the paint film. By the optimized combination of components, the gloss at 60° and 85° incident angles is controlled, solving the problem of uneven gloss leading to the positive and negative sides, and the paint film formed has a delicate hand feeling, without the need for further baking, reducing the construction steps and saving construction time, which was not foreseeable before the present application.

[0030] The details of one or more embodiments of the application are set forth in the description below. Other features, objects, and advantages of the application will be apparent from the description and from the claims.

[0031] Definitions

[0032] As used herein, "a," "an," "the," and "at least one" and similar referents used in connection with an entity describe that entity and at least one of its members or a member of its group. Thus, for example, "a" component can mean one or more components.

[0033] Where a composition is described as including or comprising particular components, it is contemplated that the composition can also consist essentially of the recited components, and that like components can be excluded, except insofar as a context forbids such exclusions. Where a method is described as including or comprising particular process steps, it is contemplated that the method can also consist essentially of the recited process steps, and that like steps can be excluded, except insofar as a context forbids such exclusions.

[0034] For convenience, only some numerical ranges are explicitly disclosed herein. However, any lower limit can be combined with any upper limit to form a range not explicitly recited; and any lower limit can be combined with any other lower limit to form a range not explicitly recited, and likewise any upper limit can be combined with any other upper limit to form a range not explicitly recited. Further, although a range is expressed as from an lower limit to an upper limit, any other limitations of the range constructed from any of the upper limit, the lower limit, and the other limitations are implicitly disclosed, but for convenience are not explicitly restated in their entirety. Further, although a range is expressed as from an lower limit to an upper limit, every point or individual value within that range is also implicitly disclosed. Thus, every point or individual value can be combined with any other point or individual value to form a new range not explicitly recited. Further, although a range is expressed as from an lower limit to an upper limit, every point or individual value within that range is also implicitly disclosed. Thus, every point or individual value can be combined with any other point or individual value to form a new range not explicitly recited.

[0035] The term "major surface" when used in the context of a substrate is the surface formed by a certain length and a certain width dimension of the substrate that is used to provide decoration.

[0036] The term "primer" when used herein refers to a coating composition that can be applied to a substrate and dried, crosslinked, or otherwise hardened to form a tack-free, continuous film having sufficient adhesion to the surface of the substrate.

[0037] The term "on" when used in the context of "applying...over a coating" includes applying a paint or coating composition directly or indirectly over another coating.

[0038] The terms "comprising" and "including," along with their derivatives, as used in the specification and claims, are not intended to be limiting.

[0039] The terms "preferred" and "preferably" refer to a determination that, in certain instances, a particular embodiment can provide certain benefits. However, other embodiments can also be preferred under the same or other circumstances. Additionally, the recitation of one or more preferred embodiments does not imply that other embodiments are not useful, and is not intended to exclude those other embodiments from the scope of the application. BRIEF DESCRIPTION OF DRAWINGS

[0040] Figure 1 A photograph schematically showing a coating having a cloth grain texture obtained from an aqueous coating composition according to the present application. DETAILED DESCRIPTION

[0041] The present application provides, in one aspect, an aqueous coating composition comprising:

[0042] a film-forming resin composition, a thickener, an environmentally friendly ester film- forming coalescent, a filler, optionally an aqueous medium, and additional additives;

[0043] wherein the thickener comprises an inorganic thickener;

[0044] wherein the filler is present in an amount of 4-6 wt.%, preferably in an amount of 4.5-5 wt.%, relative to the total weight of the aqueous coating composition; and

[0045] wherein the gloss at 60° of a coating layer formed from the aqueous coating composition differs from the gloss at 85° by no more than 0.4, preferably no more than 0.2, more preferably no more than 0.1.

[0046] In some embodiments according to the present application, the film-forming resin composition is present in the form of an aqueous dispersion of polymer particles. As used herein, the term "aqueous dispersion of polymer particles" refers to a stable dispersion of synthetic resin (i.e. polymer) in the form of microparticles in an aqueous liquid medium, optionally with the aid of suitable dispersion aids such as surfactants. Thus, the terms "aqueous latex" and "aqueous dispersion" can be used interchangeably in the present application when used in relation to polymers, unless otherwise stated. Methods of preparing aqueous latex are known in the art, for example can be prepared using emulsion polymerization processes known to the skilled person. The emulsion polymerization preparation process typically comprises the steps of dispersing polymerizable monomers in an emulsion in water, optionally under the action of suitable emulsifiers and / or dispersion stabilizers, and with the aid of stirring, and initiating the polymerization of the monomers, for example by adding an initiator.

[0047] In embodiments according to the present application, the aqueous dispersion of polymer particles is considered as the film-forming resin composition in the aqueous coating composition. On the one hand, this resin composition acts as a binder, for providing adhesion of the paint film to the substrate, and to hold the components in the aqueous coating composition, such as the filler, together and impart a certain cohesive strength to the paint film. On the other hand, this polymer particles can react with a suitable curing agent, as required, to achieve cross-linking of the polymer chains, thereby achieving a coating layer with high mechanical strength.

[0048] In some preferred embodiments of the present application, the aqueous dispersion of polymer particles comprises one or more of an aqueous dispersion of acrylic resin, an aqueous dispersion of polystyrene-acrylic resin, an aqueous dispersion of polyurethane, an aqueous dispersion of polyurethane-acrylic resin, an aqueous dispersion of epoxy resin, an aqueous dispersion of polyester, an aqueous dispersion of polyvinyl acetate, an aqueous dispersion of polysiloxane, preferably one or two of an aqueous dispersion of acrylic resin, an aqueous dispersion of polystyrene-acrylic resin, an aqueous dispersion of polyurethane, and an aqueous dispersion of polyurethane-acrylic resin, more preferably one or two of an aqueous dispersion of acrylic resin, an aqueous dispersion of polystyrene-acrylic resin.

[0049] In embodiments according to the present application, the polymer particles in the aqueous dispersion have a range of particle sizes, which can be measured by the Z-average particle size, which refers to the size of the particles determined by dynamic light scattering, for example using a Malvern Zetasizer 3000HS Microsizer. Preferably, the polymer particles of the aqueous dispersion can have a particle size in the range of 50 nm to 200 nm. The inventors of the present application surprisingly found that aqueous dispersions of polymer particles having the above-mentioned range of particle sizes are particularly suitable for formulating aqueous coating compositions, which have suitable rheological and coating properties.

[0050] In embodiments of the present application, the aqueous dispersion of polymer particles has a solids content of 30-50%. From an industrial practical point of view, aqueous dispersions of polymer particles having the above solids content are most readily available. The aqueous dispersions of polymer particles described above are either self-made or commercially available. As illustrative examples, one can use an aqueous dispersion of Dow 3311 acrylic resin commercially available from Dow, an aqueous dispersion of Allnex 6716 acrylic resin commercially available from Allnex, an aqueous dispersion of Archsol 8121 polystyrene-acrylic resin commercially available from Wanhua.

[0051] According to embodiments of the present application, the amount of the aqueous dispersion of polymer particles can vary within a wide range, and can range from about 20 wt% to about 85 wt% by weight relative to the total weight of the aqueous coating composition. In one embodiment, the aqueous coating composition comprises at least 25 wt% of the aqueous dispersion of polymer particles relative to the total weight of the aqueous coating composition. Preferably, the aqueous coating composition comprises at least 30 wt% of the aqueous dispersion of polymer particles relative to the total weight of the aqueous coating composition. More preferably, the aqueous dispersion of polymer particles is present in an amount of at least 30 wt%, at least 35 wt%, at least 40 wt%, at least 45 wt% or more relative to the total weight of the aqueous coating composition. According to the present application, the aqueous dispersion of polymer particles is present in an amount of at most 80 wt%, at most 70 wt%, at most 60 wt%, at most 50 wt% or less relative to the total weight of the aqueous coating composition.

[0052] The aqueous coating composition according to the present application further comprises a film forming aid, preferably an environmentally friendly ester film forming aid, to assist the film formation of the aqueous dispersion of polymer particles. Suitable environmentally friendly ester film forming aids include non-phthalate environmentally friendly plasticizers, preferably one or more selected from dipropylene glycol dibenzoate, epoxy acetyl methyl linseedate, diethylene glycol dibenzoate, diisononyl cyclohexane 1,2- dicarboxylate. These have good resin compatibility, resulting in better coalescence of the aqueous dispersion of polymer particles at low temperature, better viscosity stability, improved pigment stability, and good film formation of the emulsion polymer, and lower film formation temperature.

[0053] In preferred embodiments, the aqueous coating composition comprises about 1 to about 10 wt%, preferably about 1 to about 8 wt%, more preferably about 1 to 3 wt% of the environmentally friendly ester film forming aid relative to the total weight of the aqueous coating composition. Specifically, the amount of the environmentally friendly ester film forming aid comprised by the aqueous coating composition is from about 1 wt%, 2 wt%, about 3 wt%, about 4 wt%, about 5 wt% to about 10 wt%, about 9 wt% or about 8 wt% relative to the total weight of the aqueous coating composition.

[0054] The aqueous coating composition according to the present application further comprises one or more fillers. The term "filler" as used herein refers to any volume extender suitable for use in a coating, which can be organic or inorganic, for example in the form of a particle. The shape of the particle is not particularly limited and can have any suitable shape. The average particle size of the filler can vary in a wide range, for example in the range of about 10 nanometers to about 50 micrometers. Some fillers impart one or more desired properties to the composition and / or to the coating layer formed from the composition in addition to acting as a volume extender for the coating. For example, some fillers can impart a desired color to the composition and to the coating layer obtained from the composition. In this case, such a filler is also referred to as a "pigment". Some fillers can improve chemical and / or physical properties, in particular can improve the mechanical properties of the coating layer obtained from the composition. In this case, such a filler is also referred to as a "reinforcing filler".

[0055] In some embodiments according to the present application, in addition to diatomite, the filler further comprises at least one of silica, ground calcium carbonate, talc, matting wax paste, and any combination thereof. According to the present application, the total amount of the filler can vary in a wide range, for example the total amount thereof is about 5 wt% to about 55 wt%, preferably about 10 to about 50 wt%, more preferably about 20 wt% to about 45 wt% relative to the total weight of the aqueous coating composition.

[0056] Excessive amount of diatomite can result in further decrease of gloss, and beyond a certain amount, it can severely affect the final viscosity of the aqueous coating composition, and thus render the composition unusable. In preferred embodiments, the aqueous coating composition comprises 4-6 wt% diatomite, preferably 3.5-5 wt% diatomite, relative to the total weight of the aqueous coating composition. In this case, a stable surface effect and gloss uniformity can be achieved.

[0057] In embodiments according to the present application, the inorganic thickening agent is modified bentonite. As an illustrative example, bentonite commercially available from Zhejiang Fenghong can be used.

[0058] In preferred embodiments, the aqueous coating composition comprises about 0.1 wt% to about 2 wt%, preferably about 0.2 wt% to about 1.0 wt%, more preferably about 0.2 wt% to about 0.5 wt% of the inorganic thickening agent, relative to the total weight of the aqueous coating composition. Specifically, the amount of the thickening agent comprised in the aqueous coating composition is from about 0.1 wt%, about 0.2 wt%, about 0.3 wt%, about 0.4 wt%, about 0.5 wt%, about 0.6 wt%, about 0.7 wt%, about 0.8 wt%, or about 0.9 wt% to about 2.0 wt%, about 1.5 wt%, about 1.0 wt%, relative to the total weight of the aqueous coating composition.

[0059] Suitable thickening agents also include cellulose ether-based thickening agents, alkali-swellable thickening agents, polyurethane-based thickening agents, or any combination thereof, preferably polyurethane-based thickening agents, more preferably non-ionic polyurethane associative thickening agents. All types of thickening agents are commercially available. For example, as an example of a cellulose ether-based thickening agent, methylhydroxyethyl cellulose ether-based thickening agent HMHEC Plus 330 available from Aqualon Company, USA, can be used. As an example of an alkali-swellable thickening agent, TT935 available from Rohm & Haas Company, USA, can be used. As an example of a non-ionic polyurethane associative thickening agent, UCAR® RM-8W, VESMODY U300 and U905 available from Wanhua, can be used. RM-8W, UCAR® VESMODY U300 and U905 available from Wanhua.

[0060] Thus, in some preferred embodiments according to the present application, the thickening agent comprises, in addition to the inorganic thickening agent, a polyurethane-based thickening agent, preferably a non-ionic polyurethane associative thickening agent.

[0061] In some preferred embodiments of the present application, the aqueous coating composition comprises from about 0.1 wt% to about 2 wt%, preferably from about 0.1 wt% to about 1.0 wt%, more preferably from about 0.1 wt% to about 0.5 wt% of a polyurethane-based thickening agent, relative to the total weight of the aqueous coating composition. Specifically, the amount of thickening agent comprised by the aqueous coating composition is from about 0.1 wt%, about 0.2 wt%, about 0.3 wt%, about 0.4 wt%, about 0.5 wt%, about 0.6 wt%, about 0.7 wt%, about 0.8 wt%, or about 0.9 wt% to about 2.0 wt%, about 1.5 wt%, about 1.0 wt%, relative to the total weight of the aqueous coating composition.

[0062] Further, in one preferred embodiment, the thickening agent comprises a combination of an inorganic thickening agent, a cellulose ether-based thickening agent, and a polyurethane-based thickening agent.

[0063] In preferred embodiments, the aqueous coating composition comprises from about 0.1 wt% to about 2 wt%, preferably from about 0.2 wt% to about 1.0 wt% of a thickening agent, relative to the total weight of the aqueous coating composition. Specifically, the amount of thickening agent comprised by the aqueous coating composition is from about 0.1 wt%, about 0.2 wt%, about 0.3 wt%, about 0.4 wt%, about 0.5 wt%, about 0.6 wt%, about 0.7 wt%, about 0.8 wt%, or about 0.9 wt% to about 2.0 wt%, about 1.5 wt%, about 1.0 wt%, relative to the total weight of the aqueous coating composition.

[0064] The inventors of the present invention surprisingly found that by further optimization of the selection of thickening agents, including inorganic thickening agents and polyurethane-based thickening agents, the apparent particles generated in the making of the texture can be significantly reduced. In addition, by the combination of specific fillers and thickening agents, the viscosity and consistency of the waterborne coating composition can be effectively improved, providing a significant thixotropic effect.

[0065] In embodiments of the present invention, the waterborne composition can further comprise additional additives conventionally used in waterborne coating compositions that do not adversely affect the coating composition or the cured coating obtained therefrom. Suitable additives include, for example, those agents that improve the processing or manufacturing properties of the composition, enhance the aesthetics of the composition, or improve specific functional properties or characteristics of the coating composition or the cured coating obtained therefrom, such as adhesion to a substrate. Additives that can be included are, for example, carriers, emulsifiers, pigments, anti-migration aids, biocides, chain extenders, lubricants, wetting agents, biocides, plasticizers, defoamers, colorants, waxes, antioxidants, preservatives, flow control agents, thixotropic agents, dispersants, adhesion promoters, UV stabilizers, defoamers, pH adjusters, or combinations thereof. The amount of each optional ingredient is sufficient to achieve its intended purpose, but preferably, such amount does not adversely affect the coating composition or the cured coating obtained therefrom. In preferred embodiments of the present invention, suitable additional additives include dispersants, wetting agents, defoamers, humectants, pH adjusters, preservatives, biocides, or any combination thereof.

[0066] Suitable dispersants can include anionic dispersants, cationic dispersants, non-ionic dispersants, amphoteric dispersants, or any combination thereof, preferably non-ionic dispersants. All types of dispersants are commercially available. In preferred embodiments, suitable dispersants include polyacrylate dispersants, polymethacrylate dispersants, polycarboxylate dispersants, or any combination thereof. As an example of polyacrylate dispersants, polyacrylate sodium dispersant P30 available from AkzoNobel France can be used.

[0067] In preferred embodiments, the waterborne coating composition can comprise about 0.1 wt% to about 1.5 wt%, preferably about 0.2 wt% to about 1.0 wt%, more preferably about 0.5 wt% to about 0.8 wt% of the dispersant, relative to the total weight of the waterborne coating composition. Specifically, the waterborne coating composition can comprise the dispersant in an amount of from about 0.2 wt%, about 0.3 wt%, about 0.4 wt%, about 0.5 wt%, about 0.6 wt% to about 1.5 wt%, about 1.0 wt%, about 0.9 wt%, relative to the total weight of the waterborne coating composition.

[0068] Suitable wetting agents include organosilicon wetting agents, acetylenic diol wetting agents, or any combination thereof. All types of wetting agents are commercially available products. As an example of an organosilicon wetting agent, BYK 346 available from BYK-Gardner, Germany can be used.

[0069] In preferred embodiments, the aqueous coating composition comprises about 0.1 wt% to about 2 wt%, preferably about 0.1 wt% to about 1.0 wt%, more preferably about 0.1 wt% to about 0.5 wt% of a wetting agent, relative to the total weight of the aqueous coating composition. Specifically, the amount of wetting agent included in the aqueous coating composition is from about 0.2 wt%, about 0.3 wt%, about 0.4 wt%, about 0.5 wt%, about 0.6 wt%, about 0.7 wt%, about 0.8 wt%, or about 0.9 wt% to about 2.0 wt%, about 1.5 wt%, about 1.0 wt%, relative to the total weight of the aqueous coating composition.

[0070] Humectants are a type of formulation that prevent the deterioration of the freeze-thaw resistance of the coating, effectively adjust the open time of the wet film during construction, improve the operability of the product, reduce the brush marks of manual brushing and rolling, and thus improve the final film forming effect. Preferably, the humectant is a polyhydric alcohol. More preferably, the humectant includes glycerol, polyethylene glycol, propylene glycol, polyvinyl alcohol, or any combination thereof.

[0071] In preferred embodiments, the aqueous coating composition comprises about 0.5 wt% to about 4 wt%, preferably about 1 wt% to about 3 wt%, more preferably about 1 wt% to about 2.5 wt% of a humectant, relative to the total weight of the aqueous coating composition. Specifically, the amount of humectant included in the aqueous coating composition is from about 0.5 wt%, about 0.8 wt%, about 1.0 wt%, about 1.5 wt%, or about 2.0 wt% to about 4.0 wt%, about 3.5 wt%, about 3.0 wt%, about 2.5 wt%, relative to the total weight of the aqueous coating composition.

[0072] Suitable defoamers include organosiloxane defoamers, mineral oil defoamers, polyether defoamers, polyether-modified organosilicon defoamers, or any combination thereof. All types of defoamers are commercially available products. As an example of an organosiloxane defoamer, BYK 8820 available from BYK-Gardner, Germany can be used. As an example of a mineral oil defoamer, DF6007 available from De Feng, Dongguan, China can be used.

[0073] In preferred embodiments, the aqueous coating composition comprises from about 0.1 wt% to about 1 wt%, preferably from about 0.2 wt% to about 0.8 wt%, more preferably from about 0.4 wt% to about 0.6 wt% of a defoamer, relative to the total weight of the aqueous coating composition. Specifically, the aqueous coating composition comprises the defoamer in an amount from about 0.1 wt%, about 0.2 wt%, 0.3 wt%, about 0.4 wt%, about 0.5 wt%, or about 0.6 wt% to about 1.0 wt%, about 0.9 wt%, or about 0.8 wt%, relative to the total weight of the aqueous coating composition.

[0074] Suitable pH adjusters include anhydrous sodium carbonate, sodium hydroxide, potassium hydroxide, sodium bicarbonate, alcohol amine, aqueous ammonia, organic amines, or any combination thereof. In preferred embodiments, the pH adjuster includes aqueous ammonia, organic amines, sodium hydroxide, or any combination thereof.

[0075] In preferred embodiments, the aqueous coating composition comprises from about 0.1 to about 1.0 wt%, preferably from about 0.1 to about 0.4 wt%, more preferably from about 0.1 to about 0.3 wt% of a pH adjuster, relative to the total weight of the aqueous coating composition. Specifically, the aqueous coating composition comprises the pH adjuster in an amount from about 0.1 wt% or about 0.2 wt% to about 1.0 wt%, about 0.7 wt%, about 0.5 wt%, or about 0.3 wt%, relative to the total weight of the aqueous coating composition.

[0076] Suitable preservatives include isothiazolinones, benzimidazoles, substituted aromatics, organic bromines, organic amines, piperazine triazines, davehill, or any combination thereof, preferably selected from isothiazolinones, benzimidazoles, davehill, or any combination thereof. All types of preservatives are commercially available. For example, as an example of an isothiazolinone preservative, Kathon LX available from Dow Chemical, USA can be used. As an example of a benzimidazole preservative, Rocima BT NV2 available from Dow Chemical, USA can be used.

[0077] In preferred embodiments, the aqueous coating composition comprises from about 0.1 to about 1 wt%, preferably from about 0.1 to about 0.5 wt% of a preservative, relative to the total weight of the aqueous coating composition. Specifically, the aqueous coating composition comprises the preservative in an amount from about 0.1 wt%, 0.2 wt%, about 0.3 wt%, or about 0.4 wt% to about 1.0 wt%, about 0.9 wt%, about 0.7 wt%, or about 0.5 wt%, relative to the total weight of the aqueous coating composition.

[0078] Suitable fungicides include isothiazolinones, benzimidazoles, iodopropynyls, substituted aromatics, dithio carbamates, carbendazim, diuron, or any combination thereof, preferably selected from isothiazolinones, iodopropynyls, carbendazim, diuron, or any combination thereof. All types of fungicides are commercially available. For example, as an example of a carbendazim, diuron, fungicide, Rocima 350 available from Dow Chemical, USA, can be used. As an example of an isothiazolinone fungicide, XARCIN AB available from PCTS Speciality Chemicals, Singapore, can be used.

[0079] In preferred embodiments, the aqueous coating composition comprises about 0.1 to about 1 weight percent, preferably about 0.1 to about 0.5 weight percent, of the fungicide, relative to the total weight of the aqueous coating composition. In particular, the amount of the fungicide comprised by the aqueous coating composition is from about 0.1 weight percent, 0.2 weight percent, about 0.3 weight percent, or about 0.4 weight percent to about 1.0 weight percent, about 0.9 weight percent, about 0.7 weight percent, or about 0.5 weight percent, relative to the total weight of the aqueous coating composition.

[0080] Any suitable aqueous medium can be used to adjust the viscosity of the film-forming resin composition. Suitable aqueous media include water-soluble organic solvents, water, and mixtures thereof. The aqueous medium is selected to adjust the viscosity of the film-forming resin composition for further formulation.

[0081] Suitable water-soluble organic solvents include alcohols (e.g., ethanol, n-propanol, isopropanol, n-butanol, isobutanol, and the like); ketones (e.g., acetone, 2-butanone, cyclohexanone, methyl aryl ketones, ethyl aryl ketones, methyl isoamyl ketone, and the like); glycols (e.g., butyl glycol); glycol ethers (e.g., ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, propylene glycol monomethyl ether, methoxypropanol, dipropylene glycol methyl ether, and the like), glycol esters (e.g., butyl glycol acetate, methoxypropyl acetate, and the like); and mixtures thereof. Preferably, a glycol ether is used as the organic solvent.

[0082] The amount of aqueous medium included in the aqueous coating composition can vary, for example, depending on the coating method and the viscosity desired. Preferred embodiments of the aqueous coating composition include 0-30 weight percent of the aqueous medium, more preferably 2-25 weight percent of water.

[0083] The amount of each optional ingredient is sufficient to achieve its intended purpose, but preferably, such amount does not adversely affect the aqueous coating composition or the cured coating obtained therefrom. According to certain embodiments of the present application, the total amount of additional additives is in the range of about 0 weight percent to about 20 weight percent, preferably in the range of about 1 weight percent to about 10 weight percent, relative to the total weight of the aqueous coating composition.

[0084] In one embodiment of the present application, the waterborne coating composition of the present application comprises, relative to the total weight of the waterborne coating composition:

[0085] 20 to 50 wt% of an aqueous dispersion of an acrylic resin, an aqueous dispersion of a polystyrene-acrylic resin, or any combination thereof;

[0086] 0.2 to 1.5 wt% of a thickening agent;

[0087] 1 to 5 wt% of an environmentally friendly ester-based coalescent;

[0088] 5 to 55 wt% of a filler;

[0089] 1 to 10 wt% of additional additives; and

[0090] 0 to 30 wt% of an aqueous medium;

[0091] wherein the additional additives are selected from one or more of wetting agents, defoamers, humectants, dispersants, pH adjusters, bactericides, preservatives.

[0092] In one embodiment of the present application, the waterborne coating composition of the present application comprises, relative to the total weight of the waterborne coating composition:

[0093] 20 to 50 wt% of the aqueous dispersion of an acrylic resin, the aqueous dispersion of a polystyrene-acrylic resin, or any combination thereof;

[0094] 0.2 to 1.5 wt% of the thickening agent, the thickening agent comprising an inorganic thickening agent and a polyurethane thickening agent, preferably a combination of an inorganic thickening agent, a polyurethane thickening agent, and a cellulose ether thickening agent;

[0095] 1 to 5 wt% of the environmentally friendly ester-based coalescent, the environmentally friendly ester-based coalescent being a non-phthalate environmentally friendly plasticizer, preferably selected from one or more of dipropylene glycol dibenzoate, methyl epoxy acetyl linseedate, diethylene glycol dibenzoate, diisononyl cyclohexane 1,2-dicarboxylate;

[0096] 5 to 55 wt% of the filler, the filler further comprising at least one of heavy calcium powder, silica, talc powder, mat wax paste, or a combination thereof, in addition to the diatomite;

[0097] 0 to 1 wt%, preferably 0.5 to 0.8 wt%, of the dispersant, the dispersant being selected from a polyacrylate dispersant;

[0098] 0.1 to 0.5 wt.%, preferably 0.1 to 0.3 wt.% of the wetting agent, the dispersing agent is selected from silicone based wetting agent, acetylenic diol based wetting agent or any combination thereof;

[0099] 0.1 to 0.8 wt.%, preferably 0.4 to 0.6 wt.% of the defoaming agent, the defoaming agent is selected from silicone oxane defoaming agent, mineral oil based defoaming agent, polyether defoaming agent or any combination thereof;

[0100] 0.5 to 4 wt.%, preferably 1 to 3 wt.% of the humectant, the humectant is selected from glycerol, polyethylene glycol, propylene glycol, polyvinyl alcohol or any combination thereof;

[0101] 0 to 0.4 wt.%, preferably 0.1 to 0.3 wt.% of the pH adjusting agent, the pH adjusting agent is selected from ammonia, organic amine, sodium hydroxide or any combination thereof;

[0102] 0 to 0.5 wt.%, preferably 0.1 to 0.5 wt.% of the preservative, the preservative is selected from isothiazolinone, benzimidazole, Dowicil or any combination thereof;

[0103] 0 to 0.5 wt.%, preferably 0.1 to 0.5 wt.% of the bactericide, the bactericide is selected from isothiazolinone, iodopropynyl, carbendazim, diuron or any combination thereof; and

[0104] 0 to 30 wt.%, preferably 10 to 20 wt.% of the aqueous medium.

[0105] The inventors surprisingly found that by optimizing the combination of components, the gloss at 60° and 85° incident angles is controlled, the problem of uneven gloss leading to the occurrence of highlight and shadow is solved, and the paint film formed has a delicate hand feeling, does not need to be overcoated, reduces the construction steps and saves construction time, which was not predictable before the present application.

[0106] Without wishing to be bound by any theory, the inventors provide the following explanation to enable the present application to be better understood.

[0107] In the waterborne coating composition of the present application, diatomite as a filler will affect the gloss of the coating at 60° and 85° incident angles, the inventors use a specific amount of diatomite to make the surface effect gloss of the obtained coating reach a certain degree of uniformity, for example, the gloss of the coating formed from the waterborne coating composition at 60° is not more than 0.4, preferably not more than 0.2, more preferably not more than 0.1, most preferably substantially the same as the gloss at 85°; using an environmentally friendly ester film-forming additive to replace the traditional alcohol ester film-forming additive not only helps film formation, but also improves the smoothness and continuity of the grain texture and prolongs the open time of the paint film; in addition, through the further optimization of the thickening agent, the obvious particles generated in the grain making process are significantly reduced. Through the matching of specific fillers and thickening agents, the viscosity and consistency of the waterborne coating composition are effectively improved, and a significant thixotropic effect is provided.

[0108] According to the present application, the waterborne coating composition can be applied by conventional coating methods known to those of ordinary skill in the art. The coating methods include dip coating, spin coating, spray coating, curtain coating, brush coating, roller coating, and other coating methods known in the art. In one embodiment of the present application, the coating is performed using a spray coating process. In this way, a coating can be formed from the waterborne coating composition of the present application, which also falls within the scope of protection of the present application.

[0109] Therefore, in another aspect of the embodiments of the present application, there is provided a coating obtainable from the waterborne coating composition described herein, the coating having a grain texture, in particular a paint film unevenness, which is crisscrossed, similar to a woven grain texture, as shown in Figure 1 .

[0110] The waterborne coating composition of the present application can be applied in various thicknesses. In certain embodiments, the coating amount is in the range of 70-100 g / m 2 In certain embodiments of the present application, the dry film thickness of the formed coating is in the range of 15-50 microns, preferably in the range of 18-30 microns. The coating can be cured by air drying or by accelerating the curing using various drying devices familiar to those skilled in the art (e.g., an oven).

[0111] Another aspect of the embodiments of the present application provides an article comprising: a substrate having at least one major surface; and a coating formed from the waterborne coating composition according to the present application coated directly or indirectly on the major surface.

[0112] The coating compositions can be applied to a variety of different substrates using conventional coating techniques. Examples of suitable substrates include wood, metal, plastic, leather, fabric, ceramic, glass, cement board, or any combination thereof. Preferably, the waterborne coating compositions of the present application are particularly suitable for use on wood substrates. Suitable wood substrates include substrates derived from wood materials such as oak (e.g., white oak and red oak), pine (e.g., white pine and southern yellow pine), poplar, spruce, cherry, walnut, mahogany, cedar, maple, mahogany, birch, hickory, walnut, ash, etc. In addition, the wood substrate can be an engineered wood product, wherein the substrate is made from wood pieces (e.g., sheets, chips, flakes, fibers, strands).

[0113] According to the present application, the article can be prepared, for example, by the steps of: (1) providing a substrate; (2) sequentially applying and forming one or more layers of the waterborne coating composition according to the present application on the substrate using a coating and curing process to provide the substrate with a grain texture.

[0114] According to the present application, the article thus obtained can be used in end applications including, but not limited to, consumer electronics (e.g., laptop, cell phone housing), wooden furniture, household appliances (e.g., oven, coffee maker), automotive interior (e.g., panel, bracket, armrest), clothing (athletic shoes), packaging (e.g., cosmetic bottle / cap, bag), and texture films for in-mold decoration / in-mold labeling (IMD / IML) in a variety of application areas.

[0115] The present application is more particularly described in the following examples that are intended to be illustrative only, as numerous modifications and variations within the scope of the present application will be apparent to those skilled in the art. Unless otherwise noted, all parts, percentages, and ratios reported herein are on a weight basis, and all reagents used in the examples are commercially available and used without further purification, unless otherwise stated.

[0116] Examples

[0117] Test Methods

[0118] Gloss This test is used to measure the gloss of a cured coating. The Sheen Micro Glosmeter is used to evaluate the gloss at 60° and 85° according to ASTM D523.

[0119] Solids Determined according to GB / T 1725-2007 standard.

[0120] Viscosity: The viscosity was determined according to ASTM D 2196 (Determination of Rheological Properties of Non-Newtonian Materials by Rotational (Brookfield) Viscometer) using a Stormer KU viscometer.

[0121] Materials

[0122] The materials used are listed in Table 1 below.

[0123] Table 1: Materials used and related information

[0124] Trade Name Manufacturer Description SMY LT Zhejiang Fenghong Modified Bentonite Clay VESMODY U505 Wanhua Polyurethane-based Thickener TXIB Eastman Environmentally Friendly Ester-based Coalescent CELITE 490 Silica Diatomaceous Earth

[0125] Step 1: Add part of the water, dispersant, wetting agent, defoamer, humectant, and hydroxyl cellulose in sequence into a stirring container, and disperse in a blender at a medium speed of 500-800 rpm for 15 minutes until the hydroxyl cellulose particles are completely dissolved to form a premix;

[0126] Step 2: Add the PH adjuster, organically modified bentonite, diatomite, titanium dioxide, and heavy calcium powder in sequence into the premix, and disperse in a blender at a high speed of 800-1200 rpm for 20 minutes until the fineness is ≤45 μm;

[0127] Step 3: Add the aqueous dispersion of acrylic resin, and dilute the environmentally friendly high-boiling film-forming aid with a small amount of water. Disperse and add into the slurry at a medium speed of 500-800 rpm for 15 minutes.

[0128] Step 4: Add the bactericide and preservative in sequence into the slurry, and adjust the product viscosity with the thickening agent. Disperse at a high speed of 800-1200 rpm for 15 minutes in a blender. Perform related quality data detection on the slurry, such as viscosity, specific gravity, and PH value, to obtain the water-based paint composition.

[0129] Table 1: Composition and amount of the water-based paint composition

[0130]

[0131]

[0132] The water-based paint composition was scraped onto black and white checkered paper with a coater, and the gloss of the dry film was detected after drying.

[0133] The water-based paint composition was rolled onto a standard plate, and then textured with a texture device (K brand iron tooth comb, Shunde Kishbond Coating Equipment Co., Ltd.) to form a texture effect, and the surface effect was visually observed. The test results are shown in Tables 2 and 3.

[0134] Table 2: Test results

[0135]

[0136] As can be seen from the results of Table 2, with the increase of the amount of diatomite, the gloss will further decrease, and the decrease of the gloss at 85-degree incident angle is more significant than that at 60-degree incident angle; when the amount of diatomite reaches a certain range, the uniformity of the surface gloss remains stable, but when the amount of diatomite exceeds a certain range, the final viscosity of the water-based paint composition will be seriously affected, and thus the water-based paint composition cannot be used. According to the embodiments of the present application, the diatomite is present in an amount of 4-6% by weight, preferably in an amount of 3.5-5% by weight, relative to the total weight of the water-based paint composition. Through the control of the addition ratio of diatomite, a product with cloth texture can be obtained.

[0137] Table 3: Test results

[0138]

[0139] As can be seen from the results of Table 3, the different thickening systems will affect the final effect of the paint film, and through the reasonable collocation of inorganic thickening agent and polyurethane thickening agent, the present embodiment can obtain a coating film with continuous cloth texture and less particles.

[0140] Although the present application is described with reference to a large number of embodiments and examples, those skilled in the art can recognize, according to the disclosure of the present application, that other embodiments can be designed without departing from the scope and spirit of the present application.

Claims

1. A coating formed from an aqueous coating composition comprising: a film-forming resin composition, a thickening agent, an environmentally friendly ester-based film-forming coalescent, a filler, optionally an aqueous medium, and additional additives; wherein the thickening agent comprises a combination of an inorganic thickening agent, a polyurethane-based thickening agent, and a cellulose ether-based thickening agent, the inorganic thickening agent being a modified bentonite clay; wherein the filler comprises diatomaceous earth, the diatomaceous earth being present in an amount of 3.5-5 wt.%, relative to the total weight of the aqueous coating composition; wherein the coating formed from the aqueous coating composition has a gloss at 60° that differs by no more than 0.4 from a gloss at 85°; and wherein the coating has a texture of a cloth grain formed by applying the aqueous coating composition with a cloth graining device.

2. The coating of claim 1, wherein, The coating formed from the aqueous coating composition has a gloss at 60° that differs by no more than 0.2 from a gloss at 85°.

3. The coating of claim 1, wherein, The polyurethane-based thickening agent is a non-ionic polyurethane associative thickening agent.

4. The coating of claim 1, wherein, The filler further comprises at least one of silica, heavy calcium powder, talc powder, matting wax paste, and combinations thereof.

5. The coating of claim 3, wherein, The filler further comprises at least one of silica, heavy calcium powder, talc powder, matting wax paste, and combinations thereof.

6. The coating of claim 1, wherein, The environmentally friendly ester-based film-forming coalescent is a non-phthalate environmentally friendly plasticizer.

7. The coating of claim 3, wherein, The environmentally friendly ester-based film-forming coalescent is a non-phthalate environmentally friendly plasticizer.

8. The coating of claim 4, wherein, The environmentally friendly ester-based film-forming coalescent is a non-phthalate environmentally friendly plasticizer.

9. The coating of claim 5, wherein, The environmentally friendly ester-based film-forming coalescent is a non-phthalate environmentally friendly plasticizer.

10. The coating according to any one of claims 6 to 9, wherein, The environmentally friendly ester-based film-forming coalescent is selected from one or more of dipropylene glycol dibenzoate, methyl epoxy acetyl linseedate, diethylene glycol dibenzoate, diisononyl cyclohexane 1,2-dicarboxylate.

11. The coating of any one of claims 1 to 9, wherein, The film-forming resin composition comprises one or more of an aqueous dispersion of an acrylic resin, an aqueous dispersion of a polystyrene-acrylic resin, an aqueous dispersion of a polyurethane, an aqueous dispersion of a polyurethane-acrylic resin, an aqueous dispersion of an epoxy resin, an aqueous dispersion of a polyester, an aqueous dispersion of a polyvinyl acetate, an aqueous dispersion of a polysiloxane.

12. The coating of claim 11, wherein, The film-forming resin composition comprises one or both of an aqueous dispersion of an acrylic resin, an aqueous dispersion of a polystyrene-acrylic resin, an aqueous dispersion of a polyurethane, and an aqueous dispersion of a polyurethane-acrylic resin.

13. The coating of claim 11, wherein, The film-forming resin composition comprises one or both of an aqueous dispersion of an acrylic resin, an aqueous dispersion of a polystyrene-acrylic resin.

14. The coating of claim 11, wherein, The aqueous coating composition comprises: 20 to 50 wt.% of the aqueous dispersion of the acrylic resin, the aqueous dispersion of the polystyrene-acrylic resin, or any combination thereof; 0.2 to 1.5 wt.% of the thickening agent; 1 to 5 wt.% of the environmentally friendly ester-based film-forming coalescent; 5 to 55 wt.% of the filler; 1 to 10 wt.% of the additional additives; and 0 to 30 wt.% of the aqueous medium; The additional additive is selected from one or more of wetting agents, defoaming agents, humectants, dispersants, pH adjusters, bactericides, preservatives.

15. The coating of claim 14, wherein, The aqueous coating composition comprises, relative to the total weight of the aqueous coating composition: 20 to 50 wt% of the aqueous dispersion of the acrylic resin, the aqueous dispersion of the polystyrene-acrylic resin, or any combination thereof; 0.2 to 1.5 wt% of the thickening agent; 1 to 5 wt% of the environmentally friendly ester film-forming aid, which is a non-phthalate environmentally friendly plasticizer; 5 to 55 wt% of the filler, which, in addition to the diatomite, comprises at least one of heavy calcium powder, silica, talc powder, matt wax paste, or any combination thereof; 0 to 1 wt% of the dispersant, which is selected from polyacrylate dispersants; 0.1 to 0.5 wt% of the wetting agent, which is selected from silicone-based wetting agents, acetylenic diol-based wetting agents, or any combination thereof; 0.1 to 0.8 wt% of the defoaming agent, which is selected from silicone oxane defoaming agents, mineral oil-based defoaming agents, polyether defoaming agents, or any combination thereof; 0.5 to 4 wt% of the humectant, which comprises polyhydric alcohols; 0 to 0.4 wt% of the pH adjuster, which is selected from ammonia water, organic amines, sodium hydroxide, or any combination thereof; 0 to 0.5 wt% of the preservative, which is selected from isothiazolinones, benzimidazoles, Dowicil, or any combination thereof; 0 to 0.5 wt% of the bactericide, which is selected from isothiazolinones, iodoacetylenic alcohols, carbendazim, diuron, or any combination thereof; and 0 to 30 wt% of the aqueous medium.

16. The coating of claim 15, wherein, The environmentally friendly ester film-forming aid is selected from one or more of dipropylene glycol dibenzoate, epoxy acetyl linseed oil methyl ester, diethylene glycol dibenzoate, cyclohexane 1,2-dicarboxylic acid diisononyl ester.

17. The coating of claim 15, wherein, The humectant is selected from glycerol, polyethylene glycol, propylene glycol, polyvinyl alcohol, or any combination thereof.

18. An article comprising a substrate having at least one major surface; and at least one coating layer, which is directly or indirectly coated on the major surface, is a coating layer formed from the aqueous coating composition according to any one of claims 1-17.

19. The article of claim 18, wherein, The substrate comprises wood, metal, plastic, leather, fabric, ceramic, glass, cement board, or any combination thereof.

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