DESC:FIELD
The present disclosure relates to a coating composition. Particularly, the present disclosure relates to a waterborne coating composition and a process for its preparation.
DEFINITIONS
As used in the present disclosure, the following terms are generally intended to have the meaning as set forth below, except to the extent that the context in which they are used, indicate otherwise.
Whiteness index: The term “whiteness index” refers to a quantitative measure of the degree of whiteness or lightness of the paint/coating, especially its ability to reflect light.
Washability cycles: The term "washability cycles” refers to the number of cleaning cycles a painted/coated surface is withstand without significant deterioration or loss of appearance.
Contrast ratio: The term “contrast ratio” refers to a ratio of the reflectance of a film being applied on a black substrate to that of an identical film on a white substrate.
BACKGROUND
The background information herein below relates to the present disclosure but is not necessarily prior art.
Pigment volume concentration (PVC) is an important factor in the determination of opacity of the paint/coating. Conventionally, high PVC coatings are employed in the paint compositions. However, these high PVC coatings lead to poor surface finish, poor whiteness, less washability cycles and at times poor opacity (poor contrast ratio). Further, the conventional high PVC coatings, when applied with the conventional brushes and rollers, result in the rough finish and patchy appearance of the coat. Lot of variations have been introduced by modifying the components of the coating compositions such as high loading of extenders, use of high brightness extenders, use of spacers, and the like to achieve the better whiteness index and better contrast ratio. However, the use of high extenders is associated with a porosity in coating leading to scattering of light and the low loading of binder which results in inferior washability cycles and thus, poor durability of the coating.
Further, the conventional coatings, particularly high PVC coatings are not compatible to balance the properties of good surface finish, high whiteness index, high washability cycles and high opacity altogether. Even if one of the properties is achieved, the rest of the properties are not successfully attained. In addition, the conventional high PVC coatings fail to allow rheology optimization for ease of application.
Therefore, there is felt a need to provide a waterborne coating composition that obviates the drawbacks mentioned hereinabove or at least provide an alternative solution.
OBJECTS
Some of the objects of the present disclosure, which at least one embodiment herein satisfies, are as follows.
It is an object of the present disclosure is to ameliorate one or more problems of the background or to at least provide a useful alternative.
Another object of the present disclosure is to provide a waterborne coating composition.
Still another object of the present disclosure is to provide a waterborne coating composition for use in interior as well as exterior architectural walls.
Yet another object of the present disclosure is to provide a waterborne coating composition that is economical.
Still another object of the present disclosure is to provide a waterborne coating composition that has improved whiteness index (W.I.) and improved contrast ratio.
Yet another object of the present disclosure is to provide a waterborne coating composition that has improved whiteness index (W.I.) and improved contrast ratio (C.R.), thereby providing better opacity.
Still another object of the present disclosure is to provide a waterborne coating composition that has improved washability cycles.
Yet another object of the present disclosure is to provide a process for the preparation of a waterborne coating composition.
Still another object of the present disclosure is to provide a simple, efficient and eco-friendly process for the preparation of a waterborne coating composition.
Yet another object of the present disclosure is to provide a process for the preparation of a waterborne coating composition that is feasible on a large/commercial scale.
Other objects and advantages of the present disclosure will be more apparent from the following description, which is not intended to limit the scope of the present disclosure.
SUMMARY
The present disclosure relates to a waterborne coating composition and a process for its preparation.
A waterborne coating composition comprising:
a. a styrene-acrylic co-polymer emulsion having a particle size in the range of 110 nm to 170 nm and a glass transition temperature (Tg) of 20 °C;
b. a styrene-acrylic hollow emulsion having a particle size in the range of 600 nm to 700 nm;
c. a dispersion of nano-silica having a particle size in the range of 8 nm to 15 nm;
d. additives; and
e. water.
The composition comprises,
a. the styrene-acrylic co-polymer emulsion is present in an amount in the range of 2 mass% to 10 mass%;
b. the styrene-acrylic hollow emulsion is present in an amount in the range of 5 mass% to 15 mass%;
c. the dispersion of nano-silica is present in an amount in the range of 0.1 mass% to 2 mass%;
d. the additives are present in an amount in the range of 10 mass% to 60 mass%; and
e. q.s. water,
wherein the mass% of each ingredient is with respect to the total mass of the waterborne coating composition.
The mass ratio of the styrene-acrylic co-polymer emulsion to the styrene-acrylic hollow emulsion to the dispersion of nano-silica is in the range of 3:5:1 to 15:25:1.
The styrene-acrylic co-polymer emulsion contains a solid content in the range of 40 mass% to 45 mass% with respect to the total mass of the styrene-acrylic co-polymer emulsion.
The styrene-acrylic hollow emulsion contains a solid content in the range of 30 mass% to 35 mass% with respect to the total mass of the styrene-acrylic hollow emulsion.
The dispersion of nano-silica contains a solid content in the range of 29 mass% to 31 mass% with respect to the total mass of the dispersion of nano-silica.
The additive is selected from the group consisting of a dispersing agent, a co-solvent, an extender, a pigment, a defoamer, a biocide and at least one rheology modifier.
The dispersing agent is selected from ammonium salt of polyacrylic acid and ethoxylated alcohols.
The co-solvent is ester alcohol.
The extender is selected from the group consisting of calcium carbonate, talc, and sodium magnesium aluminosilicate.
The pigment is titanium dioxide.
The biocide is selected from the group consisting of benzimidazole carbamate, 2-n-octyl-4-isothiazolin-3-one and mixture of chlormethyl-/methylisothiazolone and formaldehyde.
The rheology modifier is selected from hydroxy ethyl cellulose and hydrophobically modified alkali swellable emulsion; wherein the hydrophobically modified alkali swellable emulsion is polyacarboxylic acid
The defoamer is selected from mineral oil-based defoamer and hydrocarbon oil based defoamer.
A process for the preparation of a waterborne coating composition, the process comprising the following steps:
i. mixing predetermined amounts of an extender, a pigment and a dispersing agent, a biocide, a defoamer and at least one rheology modifier in a predetermined amount of water followed by stirring at a first predetermined speed for a first predetermined time period to obtain a mixture; and
ii. sequentially, adding predetermined amounts of a styrene-acrylic co-polymer emulsion, a styrene-acrylic hollow emulsion, a dispersion of nano-silica, and a co-solvent in the mixture under stirring and further maintaining under stirring at a second predetermined speed for a second predetermined time period to obtain the waterborne coating composition.
The styrene-acrylic co-polymer emulsion has a particle size in the range of 110 nm to 170 nm and a glass transition temperature (Tg) of 20 °C.
The styrene-acrylic hollow emulsion has a particle size in the range of 600 nm to 700 nm.
The dispersion of nano-silica has a particle size in the range of 8 nm to 15 nm.
The mass ratio of the styrene-acrylic co-polymer emulsion to the styrene-acrylic hollow emulsion to the dispersion of nano-silica is in the range of 3:5:1 to 15:25:1.
The styrene-acrylic co-polymer emulsion contains a solid content in the range of 40 mass% to 45 mass% with respect to the total mass of the styrene-acrylic co-polymer emulsion.
The styrene-acrylic hollow emulsion contains a solid content in the range of 30 mass% to 35 mass% with respect to the total mass of the styrene-acrylic hollow emulsion.
The dispersion of nano-silica contains a solid content in the range of 29 mass% to 31 mass% with respect to the total mass of the dispersion of nano-silica.
In accordance with the present disclosure, the predetermined amount of
a. the styrene-acrylic co-polymer emulsion is in the range of 2 mass% to 10 mass%;
b. the styrene-acrylic hollow emulsion is in the range of 5 mass% to 15 mass%;
c. the dispersion of nano-silica is in the range of 0.1 mass% to 2 mass%;
d. the extender is in the range of 30 mass% to 50 mass%;
e. the pigment is in the range of 0 mass% to 1 mass%;
f. the dispersing agent is in the range of 0.2 mass% to 0.6 mass%;
g. the biocide is in the range of 0.2 mass% to 0.4 mass%;
h. the co-solvent is in the range of 0.2 mass% to 0.4 mass%;
i. the defoamer is in the range of 0.15 mass% to 0.3 mass%;
j. the rheology modifier is in the range of 0.1 mass% to 2 mass%; and
k. water is in the range of 40 mass% to 50 mass%,
wherein the mass% of each ingredient is with respect to the total mass of the waterborne coating composition.
The extender is selected from the group consisting of calcium carbonate, talc and sodium magnesium aluminosilicate.
The dispersing agent is selected from ammonium salt of polyacrylic acid and ethoxylated alcohols;
The co-solvent is ester alcohol.
The pigment is titanium dioxide.
The biocide is selected from benzimidazole carbamate, 2-n-octyl-4- isothiazolin-3-one and a mixture of chlormethyl-/methylisothiazolone and formaldehyde.

The defoamer is selected from mineral oil-based defoamer and hydrocarbon oil based defoamer.
The rheology modifier is selected from hydroxy ethyl cellulose and hydrophobically modified alkali swellable emulsion; wherein the hydrophobically modified alkali swellable emulsion is polyacarboxylic acid.
The first predetermined speed is in the range of 10 m/s to 25 m/s.
The second predetermined speed is in the range of 500 rpm to 3000 rpm.
The first predetermined time period is in the range of 10 minutes to 50 minutes.
The second predetermined time period is in the range of 10 minutes to 50 minutes.
The waterborne coating composition is characterized by having at least one of the following:
• whiteness index in the range of 90% to 95% measured as per ASTM E313-20 method;
• contrast ratio in the range of 0.90 to 0.95 measured as per ASTM D2805-11 method; and
• washability cycles in the range of 800 to 1300 measured as per IS 15489:2013 method.
DETAILED DESCRIPTION
The present disclosure relates to a coating composition. Particularly, the present disclosure relates to a waterborne coating composition and a process for its preparation.
Embodiments, of the present disclosure, will now be described herein. Embodiments are provided so as to thoroughly and fully convey the scope of the present disclosure to the person skilled in the art. Numerous details, are set forth, relating to specific components, and methods, to provide a complete understanding of embodiments of the present disclosure. It will be apparent to the person skilled in the art that the details provided in the embodiments should not be construed to limit the scope of the present disclosure. In some embodiments, well-known processes, well-known apparatus structures, and well-known techniques are not described in detail.
The terminology used, in the present disclosure, is only for the purpose of explaining a particular embodiment and such terminology shall not be considered to limit the scope of the present disclosure. As used in the present disclosure, the forms "a,” "an," and "the" may be intended to include the plural forms as well, unless the context clearly suggests otherwise. The terms "comprises," "comprising," “including,” and “having,” are open ended transitional phrases and therefore specify the presence of stated features, integers, steps, operations, elements, modules, units, and/or components, but do not forbid the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. The particular order of steps disclosed in the method and process of the present disclosure is not to be construed as necessarily requiring their performance as described or illustrated. It is also to be understood that additional or alternative steps may be employed.
As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed elements.
The terms first, second, third, etc., should not be construed to limit the scope of the present disclosure as the aforementioned terms may be only used to distinguish one element, component, region, layer or section from another component, region, layer, or section. Terms such as first, second, third etc., when used herein do not imply a specific sequence or order unless clearly suggested by the present disclosure.
Conventionally used high pigment volume concentration (PVC) coatings lead to give poor surface finish, reduced whiteness, lower washability, and sometimes, inadequate opacity. When applied with brushes and rollers, they may also result in a rough or patchy appearance. To overcome on this, modifications like high extender loading, brighter extenders, and spacers have been introduced. However, use of high extender creates a porous coating with low binder content, leading to poor durability and washability. Further, the conventional high PVC coatings are not compatible to balance the properties of good surface finish, high whiteness index, high washability cycles and high opacity altogether. Even if one of the properties is achieved, the rest of the properties are not successfully attained. Also, conventional high PVC coatings fail to allow rheology optimization for ease of application.
The present disclosure provides a waterborne coating composition and a process for its preparation.
In an aspect, the present disclosure provides a waterborne coating composition.
The waterborne coating composition comprising:
a. a styrene-acrylic co-polymer emulsion is having a particle size in the range of 110 nm to 170 nm and a glass transition temperature (Tg) of 20 °C;
b. a styrene-acrylic hollow emulsion is having a particle size in the range of 600 nm to 700 nm;
c. a dispersion of nano-silica is having a particle size in the range of 8 nm to 15 nm;
d. additives; and
e. water.
In an embodiment of the present disclosure, the waterborne coating composition is a multicomponent coating system.
Waterborne coating composition refers to a composition that uses water as a solvent to disperse the ingredients used to make the coating or paint.
In an exemplary embodiment of the present disclosure, the styrene-acrylic co-polymer emulsion has a particle size of 150 nm.
In accordance with the present disclosure, the particle size of the styrene-acrylic co-polymer contributes to the effective film formation, ensuring that the coating adheres well to surfaces and forms a continuous and smooth layer. This film integrity is crucial for washability because it reduces the risk of the coating breaking down or losing its integrity under mechanical stress, such as scrubbing or repeated washing. The moderate glass transition temperature (Tg) of 20°C ensures flexibility at room temperature, which helps maintain adhesion and resist cracking, thereby improving washability. The styrene-acrylic co-polymer provides smooth film formation and flexibility which is crucial for maintaining washability.
In an exemplary embodiment of the present disclosure, the styrene-acrylic hollow emulsion has a particle size of 650 nm.
In accordance with the present disclosure, the styrene-acrylic hollow emulsion particles having light scattering effect which leads to improved opacity contributing to improved brightness and contrast ratio without adding significant thickness to the film. This light-scattering effect maintains the coating’s bright and white appearance over time, even after more washability cycles.
In an exemplary embodiment of the present disclosure, a dispersion of nano-silica has a particle size of 12 nm.
In accordance with the present disclosure, the nano-silica enhances abrasion resistance and film strength, providing improved durability and ensuring that the optical properties of the coating remain intact over time.
The combination of styrene-acrylic co-polymer emulsion, styrene-acrylic hollow emulsion, and nano-silica dispersion provides a synergistic effect that provides efficient particle packing of small and large particles, which results in a stronger, more durable film. Further, the synergistic combination of the coating composition of the present disclosure provides coatings with significantly enhanced washability cycles, whiteness index, and contrast ratio. The particle size of the co-polymer (styrene-acrylic co-polymer emulsion) ensures good film formation and adhesion, the hollow particles (styrene-acrylic hollow emulsion) provide excellent light scattering for opacity and whiteness, and the dispersion of nano-silica reinforcement improves durability and wear resistance.
In an embodiment of the present disclosure, the waterborne coating composition comprises,
a. the styrene-acrylic co-polymer emulsion in an amount in the range of 2 mass% to 10 mass%;
b. the styrene-acrylic hollow emulsion in an amount in the range of 5 mass% to 15 mass%;
c. the dispersion of nano-silica in an amount in the range of 0.1 mass% to 2 mass%;
d. the additives in an amount in the range of 10 mass% to 60 mass%; and
e. q.s. water,
wherein the mass% of each ingredient is with respect to the total mass of the waterborne coating composition.
In another embodiment of the present disclosure, the waterborne coating composition, comprises
a. the styrene-acrylic co-polymer emulsion in an amount in the range of 5 mass% to 6 mass%;
b. the styrene-acrylic hollow emulsion in an amount in the range of 8 mass% to 10 mass%;
c. the dispersion of nano-silica in an amount in the range of 0.2 mass% to 0.8 mass%;
d. the additives in an amount in the range of 20 mass% to 50 mass%; and
e. q.s. water,
wherein the mass% of each ingredient is with respect to the total mass of the waterborne coating composition.
In an exemplary embodiment of the present disclosure, the waterborne coating composition, comprises
a. the styrene-acrylic co-polymer emulsion in an amount of 5.5 mass%;
b. the styrene-acrylic hollow emulsion in an amount of 9.0 mass%;
c. the dispersion of nano-silica in an amount of 0.5 mass%;
d. the additives in an amount of 40.64 mass%; and
e. water in an amount of 44.36 mass%,
wherein the mass% of each ingredient is with respect to the total mass of the waterborne coating composition.
In an embodiment of the present disclosure, a mass ratio of the styrene-acrylic co-polymer emulsion to the styrene-acrylic hollow emulsion to the dispersion of nano-silica is in the range of 3:5:1 to 15:25:1. In an exemplary embodiment of the present disclosure, the mass ratio of the styrene-acrylic co-polymer emulsion to the styrene-acrylic hollow emulsion to the dispersion of nano-silica is 11:18:1.
In an embodiment of the present disclosure, the styrene-acrylic co-polymer emulsion contains a solid content in the range of 40 mass% to 45 mass% with respect to the total mass of the styrene-acrylic co-polymer emulsion. In an exemplary embodiment of the present disclosure, the styrene-acrylic co-polymer emulsion contains a solid content is of 42 mass% with respect to the total mass of the styrene-acrylic co-polymer emulsion.
In an embodiment of the present disclosure, the styrene-acrylic hollow emulsion contains a solid content in the range of 30 mass% to 35 mass% with respect to the total mass of the styrene-acrylic hollow emulsion. In an exemplary embodiment of the present disclosure, the styrene-acrylic hollow emulsion contains a solid content is of 31 mass% with respect to the total mass of the styrene-acrylic hollow emulsion.
In an embodiment of the present disclosure, the dispersion of nano-silica contains a solid content in the range of 29 mass% to 31 mass% with respect to the total mass of the dispersion of nano-silica. In an exemplary embodiment of the present disclosure, the dispersion of nano-silica contains a solid content is of 29.5 mass% with respect to the total mass of the dispersion of nano-silica.
The solid content in emulsions of waterborne coating composition indicates the proportion of non-volatile materials that remain after water evaporates. It affects film thickness, durability, application ease, and environmental impact. Solid content will impact overall composition in solids excluding water.
In an embodiment of the present disclosure, the additive is selected from the group consisting of a dispersing agent, a co-solvent, an extender, a pigment, a biocide, a defoamer and at least one rheology modifier.
In an embodiment of the present disclosure, the total amount of additives is present in an amount in the range of 10 mass% to 60 mass%. In an exemplary embodiment of the present disclosure, the total amount of additives is present in an amount of 40.64 mass%.
In an embodiment of the present disclosure, the dispersing agent is selected from ammonium salt of polyacrylic acid and ethoxylated alcohols. In an exemplary embodiment of the present disclosure, the dispersing agent is ethoxylated alcohols.
In an embodiment of the present disclosure, the dispersing agent is present in an amount in the range of 0.2 mass% to 0.6 mass% with respect to the total mass of the waterborne coating composition. In an exemplary embodiment of the present disclosure, the dispersing agent is present in an amount of 0.48 mass% with respect to the total mass of the waterborne coating composition.
In an embodiment of the present disclosure, the co-solvent is ester alcohol. In an embodiment of the present disclosure, the co-solvent is 2,2,4-Trimethyl-1,3-pentanediol monoisobutyrate.
In an embodiment of the present disclosure, the co-solvent is present in an amount in the range of 0.2 mass% to 0.4 mass% with respect to the total mass of the waterborne coating composition. In an exemplary embodiment of the present disclosure, the co-solvent is present in an amount of 0.3 mass% with respect to the total mass of the waterborne coating composition.
In an embodiment of the present disclosure, the extender is selected from the group consisting of calcium carbonate, talc and sodium magnesium aluminosilicate. In an exemplary embodiment of the present disclosure, the extender is talc. In another exemplary embodiment of the present disclosure, the extender is sodium magnesium aluminosilicate.
In an embodiment of the present disclosure, the extender is present in an amount in the range of 30 mass% to 50 mass% with respect to the total mass of the waterborne coating composition. In an exemplary embodiment of the present disclosure, the extender is present in an amount of 38 mass% with respect to the total mass of the waterborne coating composition.
In an embodiment of the present disclosure, pigment is titanium dioxide.
In an embodiment of the present disclosure, pigment is rutile titanium dioxide. In an exemplary embodiment of the present disclosure, the pigment is rutile titanium dioxide.
In an embodiment of the present disclosure, the pigment is present in an amount in the range of 0 mass% to 1 mass% with respect to the total mass of the waterborne coating composition. In an exemplary embodiment of the present disclosure, the pigment is present in an amount of 0.5 mass% with respect to the total mass of the waterborne coating composition.
In an embodiment of the present disclosure, the biocide is selected benzimidazole carbamate, 2-n-octyl-4-isothiazolin-3-one and mixture of chlormethyl-/methylisothiazolone and formaldehyde. In an exemplary embodiment of the present disclosure, the biocide is mixture of chlormethyl-/methylisothiazolone and formaldehyde.
In an embodiment of the present disclosure, the biocide is present in an amount in the range of 0.2 mass% to 0.4 mass% with respect to the total mass of the waterborne coating composition. In an exemplary embodiment of the present disclosure, the biocide is present in an amount of 0.23 mass% with respect to the total mass of the waterborne coating composition.
In an embodiment of the present disclosure, the defoamer is selected mineral oil-based defoamer and hydrocarbon oil based defoamer. In an exemplary embodiment of the present disclosure, the defoamer is hydrocarbon oil based defoamer.
In an embodiment of the present disclosure, the defoamer is present in an amount in the range of 0.15 mass% to 0.3 mass% with respect to the total mass of the waterborne coating composition. In an exemplary embodiment of the present disclosure, the defoamer is present in an amount of 0.2 mass% with respect to the total mass of the waterborne coating composition.
In an embodiment of the present disclosure, the rheology modifier is a hydrophobically modified alkali swellable emulsion and a hydroxy ethyl cellulose. In an embodiment, the hydrophobically modified alkali swellable emulsion is polyacarboxylic acid.
In an embodiment of the present disclosure, the rheology modifier is present in an amount in the range of 0.1 mass% to 2 mass% with respect to the total mass of the waterborne coating composition. In an exemplary embodiment of the present disclosure, the rheology modifier is 0.93 mass% with respect to the total mass of the waterborne coating composition
In an embodiment of the present disclosure, the hydrophobically modified alkali swellable emulsion is present in an amount in the range of 0.1 mass% to 1 mass% with respect to the total mass of the waterborne coating composition. In an exemplary embodiment of the present disclosure, the hydrophobically modified alkali swellable emulsion is 0.42 mass% with respect to the total mass of the waterborne coating composition.
In an embodiment of the present disclosure, the hydroxy ethyl cellulose is present in an amount in the range of 0.2 mass% to 1 mass% with respect to the total mass of the waterborne coating composition. In an exemplary embodiment of the present disclosure, the hydroxy ethyl cellulose is 0.51 mass% with respect to the total mass of the waterborne coating composition.
In another aspect, the present disclosure provides a process for the preparation of a waterborne coating composition.
The process for the preparation of a waterborne coating composition comprises the following steps:
i. mixing predetermined amounts of an extender, a pigment and a dispersing agent, a biocide, a defoamer and at least one rheology modifier in a predetermined amount of water followed by stirring at a first predetermined speed for a first predetermined time period to obtain a mixture; and
ii. sequentially, adding predetermined amounts of a styrene-acrylic co-polymer emulsion, a styrene-acrylic hollow emulsion, a dispersion of nano-silica, and a co-solvent in the mixture under stirring and further maintaining under stirring at a second predetermined speed for a second predetermined time period to obtain the waterborne coating composition.
The process is described in detail.
In a first step, predetermined amounts of an extender, a pigment and a dispersing agent, a defoamer, a biocide, and at least one rheology modifier is mixed in a predetermined amount of water followed by stirring at a first predetermined speed for a first predetermined time period to obtain a mixture.
In an embodiment of the present disclosure, the extender is selected from the group consisting of calcium carbonate, talc and sodium magnesium aluminosilicate. In an exemplary embodiment of the present disclosure, the extender is talc. In another exemplary embodiment of the present disclosure, the extender is sodium magnesium aluminosilicate.
In an embodiment of the present disclosure, the pigment is titanium dioxide.
In an embodiment of the present disclosure, a rutile titanium dioxide. In exemplary embodiment of the present disclosure, the pigment is rutile titanium dioxide.
In an embodiment of the present disclosure, the pigment is present in an amount in the range of 0 mass% to 1 mass% with respect to the total mass of the waterborne coating composition. In an exemplary embodiment of the present disclosure, the pigment is present in an amount of 0.5 mass% with respect to the total mass of the waterborne coating composition.
In an embodiment of the present disclosure, the dispersing agent is selected from ammonium salt of polyacrylic acid and ethoxylated alcohols. In an exemplary embodiment of the present disclosure, the dispersing agent is ethoxylated alcohols.
In an embodiment of the present disclosure, the dispersing agent is present in an amount in the range of 0.2 mass% to 0.6 mass% with respect to the total mass of the waterborne coating composition. In an exemplary embodiment of the present disclosure, the dispersing agent is present in an amount of 0.48 mass% with respect to the total mass of the waterborne coating composition.
In an embodiment of the present disclosure, the biocide is selected from the group consisting of benzimidazole carbamate, 2-n-octyl-4-isothiazolin-3-one and mixture of chlormethyl-/methylisothiazolone and formaldehyde. In an exemplary embodiment of the present disclosure, the biocide is mixture of chlormethyl-/methylisothiazolone and formaldehyde.
In an embodiment of the present disclosure, the biocide is present in an amount in the range of 0.2 mass% to 0.4 mass% with respect to the total mass of the waterborne coating composition. In an exemplary embodiment of the present disclosure, the biocide is present in an amount of 0.23 mass% with respect to the total mass of the waterborne coating composition.
In an embodiment of the present disclosure, the defoamer is selected from mineral oil-based defoamer and hydrocarbon oil based defoamer. In an exemplary embodiment of the present disclosure, the defoamer is hydrocarbon oil based.
In an embodiment of the present disclosure, the defoamer is present in an amount in the range of 0.15 mass% to 0.3 mass% with respect to the total mass of the waterborne coating composition. In an exemplary embodiment of the present disclosure, the defoamer is present in an amount of 0.2 mass% with respect to the total mass of the waterborne coating composition.
In an embodiment of the present disclosure, the rheology modifier is a hydrophobically modified alkali swellable emulsion and a hydroxy ethyl cellulose. In an embodiment, the hydrophobically modified alkali swellable emulsion is polyacarboxylic acid.
In an embodiment of the present disclosure, the rheology modifier is present in an amount in the range of 0.1 mass% to 2 mass% with respect to the total mass of the waterborne coating composition. In an exemplary embodiment of the present disclosure, the rheology modifier is 0.93 mass% with respect to the total mass of the waterborne coating composition
In an embodiment of the present disclosure, the hydrophobically modified alkali swellable emulsion is present in an amount in the range of 0.1 mass% to 1 mass% with respect to the total mass of the waterborne coating composition. In an exemplary embodiment of the present disclosure, the hydrophobically modified alkali swellable emulsion is 0.42 mass% with respect to the total mass of the waterborne coating composition.
In an embodiment of the present disclosure, the hydroxy ethyl cellulose is present in an amount in the range of 0.2 mass% to 1 mass% with respect to the total mass of the waterborne coating composition. In an exemplary embodiment of the present disclosure, the hydroxy ethyl cellulose is 0.51 mass% with respect to the total mass of the waterborne coating composition.
In an embodiment of the present disclosure, the first predetermined speed is a peripheral stirring speed.
In an embodiment of the present disclosure, the first predetermined peripheral stirring speed is in the range of 10 m/s to 25 m/s. In an exemplary embodiment of the present disclosure, the first predetermined peripheral stirring speed is 12 m/s.
In an embodiment of the present disclosure, the peripheral stirring speed plays a vital role in achieving effective dispersion by breaking down particle clusters, enhancing uniformity, and ensuring the stability of the mixture.
In an embodiment of the present disclosure, the first predetermined time period is in the range of 10 minutes to 50 minutes. In an exemplary embodiment of the present disclosure, the first predetermined time period is 30 minutes.
In a second step, predetermined amounts of a styrene-acrylic co-polymer emulsion, a styrene-acrylic hollow emulsion, a dispersion of nano-silica, and a co-solvent are sequentially added in the mixture under stirring and further maintained under stirring at a second predetermined speed for a second predetermined time period to obtain the waterborne coating composition.
In an embodiment of the present disclosure, a mass ratio of the styrene-acrylic co-polymer emulsion to the styrene-acrylic hollow emulsion to the dispersion of nano-silica is in the range of 3:5:1 to 15:25:1. In an exemplary embodiment of the present disclosure, the mass ratio of the styrene-acrylic co-polymer emulsion to the styrene-acrylic hollow emulsion to the dispersion of nano-silica is 11:18:1.
The mass ratio of the styrene-acrylic co-polymer emulsion to the styrene-acrylic hollow emulsion to the dispersion of nano-silica of the present disclosure provides the balance between the properties such as opacity, washability cycles and whiteness index of the waterborne coating composition.
In an embodiment of the present disclosure, the styrene-acrylic co-polymer emulsion has a particle size in the range of 110 nm to170 nm and a glass transition temperature (Tg) of 20 °C. In an exemplary embodiment of the present disclosure, the styrene-acrylic co-polymer emulsion has a particle size of 150 nm.
In an embodiment of the present disclosure, the styrene-acrylic hollow emulsion has a particle size in the range of 600 nm to 700 nm. In an exemplary embodiment of the present disclosure, the styrene-acrylic hollow emulsion has a particle size of 650 nm.
In an embodiment of the present disclosure, the dispersion of nano-silica has a particle size in the range of 8 nm to 15 nm. In an exemplary embodiment of the present disclosure, a dispersion of nano-silica has a particle size of 12 nm.
In an embodiment of the present disclosure, the styrene-acrylic co-polymer emulsion contains a solid content in the range of 40 mass% to 45 mass% with respect to the total mass of the styrene-acrylic co-polymer emulsion. In an exemplary embodiment of the present disclosure, the styrene-acrylic co-polymer emulsion contains a solid content is of 42 mass% with respect to the total mass of the styrene-acrylic co-polymer emulsion.
In an embodiment of the present disclosure, the styrene-acrylic hollow emulsion contains a solid content in the range of 30 mass% to 35 mass% with respect to the total mass of the styrene-acrylic hollow emulsion. In an exemplary embodiment of the present disclosure, the styrene-acrylic hollow emulsion contains a solid content is of 31 mass% with respect to the total mass of the styrene-acrylic hollow emulsion.
In an embodiment of the present disclosure, the dispersion of nano-silica contains a solid content in the range of 29 mass% to 31 mass% with respect to the total mass of the dispersion of nano-silica. In an exemplary embodiment of the present disclosure, the dispersion of nano-silica contains a solid content is of 29.5 mass% with respect to the total mass of the dispersion of nano-silica.
In an embodiment of the present disclosure, the co-solvent is ester alcohol. In an embodiment of the present disclosure, the co-solvent is 2,2,4-Trimethyl-1,3-pentanediol monoisobutyrate.
In an embodiment of the present disclosure, the co-solvent is present in an amount in the range of 0.2 mass% to 0.4 mass% with respect to the total mass of the waterborne coating composition. In an exemplary embodiment of the present disclosure, the co-solvent is present in an amount of 0.3 mass% with respect to the total mass of the waterborne coating composition.
In an embodiment of the present disclosure, the second predetermined speed is in the range of 500 rpm to 3000 rpm. In an exemplary embodiment of the present disclosure, the second predetermined speed is 1500 rpm.
In an embodiment of the present disclosure, the second predetermined time period is in the range of 10 minutes to 50 minutes. In an exemplary embodiment of the present disclosure, the second predetermined time period is 30 minutes.
In an embodiment of the present disclosure, the waterborne coating composition comprises:
a. the styrene-acrylic co-polymer emulsion in an amount in the range of 2 mass% to 10 mass%;
b. the styrene-acrylic hollow emulsion in an amount in the range of 5 mass% to 15 mass%;
c. the dispersion of nano-silica in an amount in the range of 0.1 mass% to 2 mass%;
d. the extender in an amount in the range of 30 mass% to 50 mass%;
e. the pigment in an amount in the range of 0 mass% to 1 mass%;
f. the dispersing agent in an amount in the range of 0.2 mass% to 0.6 mass%;
g. the biocide in an amount in the range of 0.2 mass% to 0.4 mass%;
h. the co-solvent in an amount in the range of 0.2 mass% to 0.4 mass%;
i. the rheology modifier in an amount in the range of 0.1 mass% to 2 mass%;
j. the defoamer present in an amount in the range of 0.15 mass% to 0.3 mass%; and
k. water in an amount in the range of 40 mass% to 50 mass%,
wherein the mass% of each ingredient is with respect to the total mass of the waterborne coating composition.
In an exemplary embodiment of the present disclosure, the waterborne coating composition, comprises:
a. the styrene-acrylic co-polymer emulsion in an amount of 5.5 mass%;
b. the styrene-acrylic hollow emulsion in an amount of 9.0 mass%;
c. the dispersion of nano-silica in an amount of 0.5 mass%;
d. the extender in an amount of 38 mass%;
e. the pigment in an amount of 0.5 mass%;
f. the dispersing agent in an amount of 0.48 mass%;
g. the biocide in an amount of 0.23 mass%;
h. the co-solvent in an amount of 0.3 mass%;
i. the defoamer in an amount of 0.2 mass%;
j. the rheology modifier in an amount of 0.93 mass%; and
k. water in an amount of 44.36 mass%,
wherein the mass% of each ingredient is with respect to the total mass of the waterborne coating composition.
The combination of all the ingredients of the waterborne coating composition allow for rheology optimization that results in ease of application enabling smooth finish and non-patchy appearance.
In accordance with the present disclosure, the waterborne coating composition has excellent stability without phase separation and without viscosity change at various adverse condition i.e., stable at hot condition 55 °C for 30 days and cold condition -5°C for 15 days.
In an embodiment of the present disclosure, the waterborne coating composition is characterized by having at least one of the following:
• whiteness index in the range of 90% to 95% measured as per ASTM E313-20 method;
• contrast ratio in the range of 0.90 to 0.95 measured as per ASTM D2805-11 method; and
• washability cycles in the range of 800 to 1300 measured as per IS 15489:2013 method.
In an embodiment of the present disclosure, the whiteness index (W.I.), contrast ratio (C.R.) and washability cycles are obtained at a pigment volume ratio (PVC) more than 70%.
Conventionally, whiteness index (W.I.) and contrast ratio (C.R.) of high PVC architectural coatings are achieved through the use high loading of extenders. The high dosage of extenders introduces porosity in the coatings and with the low loading of binder leads to inferior washability cycles and thus poor durability of the coating.
The commercially available coating compositions do not help optimizing the properties including W.I, C.R., and washability cycles together at the same time, particularly in high pigment volume concentration (PVC) coatings. For high PVC coatings, it is observed that if W.I. and C.R. is improved the washability property is negatively affected and vice-versa.
The present disclosure is directed toward low cost coating composition without affecting the properties like surface finish, washability cycles, whiteness and opacity of the coating. Moreover, the present disclosure provides waterborne coating composition with W.I. of more than 90%, C.R. of more than 0.9 and washability cycles of more than 800. Further, the composition having excellent stability without phase separation and without viscosity change at various adverse condition that is the composition is stable at hot condition 55 °C for 30 days and cold condition -5°C for 15 days. Furthermore, the coating composition has rheology optimization for ease of application resulting into smooth finish and less patchiness specially as compared to high PVC coating compositions.
The waterborne coating composition of the present disclosure used for interior coating primarily used on masonry surfaces and used as a self-priming topcoat with first coat applied as a primer and subsequent coats for topcoat. Further, the composition also be applicable to exterior application with appropriate formulation enhancements for outdoor exposure and weatherability.
The foregoing description of the embodiments has been provided for purposes of illustration and not intended to limit the scope of the present disclosure. Individual components of a particular embodiment are generally not limited to that particular embodiment, but are interchangeable. Such variations are not to be regarded as a departure from the present disclosure, and all such modifications are considered to be within the scope of the present disclosure.
The present disclosure is further described in light of the following experiments which are set forth for illustration purpose only and not to be construed for limiting the scope of the disclosure. The following experiments can be scaled up to industrial/commercial scale and the results obtained can be extrapolated to industrial scale.
EXPERIMENTAL DETAILS
Experiment 1: Process for the preparation of the waterborne coating composition in accordance with the present disclosure
General procedure:
Predetermined amounts of an extender, a pigment, a dispersing agent, a biocide, a defoamer, at least one rheology modifier were mixed in a predetermined amount of water followed by stirring at a first predetermined speed for a first predetermined time period to obtain a mixture. Predetermined amounts of a styrene-acrylic co-polymer emulsion, a styrene-acrylic hollow emulsion, a dispersion of nano-silica and a co-solvent were sequentially added in the mixture under stirring and further maintained under stirring at a second predetermined speed for a second predetermined time period to obtain the waterborne coating composition.
The waterborne coating composition were prepared in Examples 1 to 8 by following the general procedure as above. The predetermined amounts of the specific ingredients of the waterborne coating composition are given in Table 1.
Table 1: Waterborne coating compositions prepared in accordance with the present disclosure
Example No. Waterborne coating composition
Styrene-acrylic co-polymer emulsion
(mass%) styrene-acrylic hollow emulsion
(mass%) Dispersion of nano-silica
(mass%) Additives
Dispersing agent
(mass%) Co-solvent
(mass%) Extenders
(mass%) Pigment
(mass%) defoamer
(mass%) Biocide
(mass%) Rheology modifier
(mass%) Water
(mass%)
hydroxyethyl cellulose polyacarboxylic acid
1. 4.84 9 0.5 0.48 0.3 38 0.5 0.2 0.23 0.51 0.42 45.02
2. 5.5 9 0.5 0.48 0.3 38 0.5 0.2 0.23 0.51 0.42 44.36
3. 6.16 9 0.5 0.48 0.3 38 0.5 0.2 0.23 0.51 0.42 43.7
4. 5.5 7 0.5 0.48 0.3 38 0.5 0.2 0.23 0.51 0.42 46.36
5. 5.5 9 0.5 0.48 0.3 38 0.5 0.2 0.23 0.51 0.42 44.36
6. 5.5 11 0.5 0.48 0.3 38 0.5 0.2 0.23 0.51 0.42 42.36
7. 5.5 9 1 0.48 0.3 38 0.5 0.2 0.23 0.51 0.42 43.86
8. 5.5 9 1.5 0.48 0.3 38 0.5 0.2 0.23 0.51 0.42 43.36
For the sake of brevity, multiple number of experiments are not included in the specification. However, the other ingredients having similar functionality can be used in the preparation of the waterborne coating composition of the present disclosure and the coating composition will give similar results.
Experiment 2: Performance study of the waterborne coating composition prepared in accordance with the present disclosure
The properties such as whiteness index, contrast ratio and washability cycles were determined for Examples 1 to 8 of the waterborne coating compositions, prepared in the Experiment 1 of the present disclosure by using standard methods.
i. Determination of washability cycles by using IS 15489:2013 method:
The washability cycles of the waterborne coating compositions prepared in examples 1 to 8 were studied by using IS 15489:2013 method.

ii. Determination of whiteness index (W.I.) by using ASTM E313-20 method:
The whiteness index (W.I.) of the waterborne coating compositions prepared in examples 1 to 8 were studied by using ASTM E313-20 method.

iii. Determination of contrast ratio (C.R.) by using ASTM D2805-11 method:
The contrast ratio (C.R.) of the waterborne coating compositions prepared in examples 1 to 8 were studied by using ASTM D2805-11 method.
The results obtained for the studies (i) to (iii) for the determination of washability cycles, whiteness index and contrast ratio respectively for examples 1 to 8 of the waterborne coating compositions are represented in the Table 2.
Table 2: Results of the performance studies of waterborne coating compositions 1 to 8
Examples Properties
Whiteness index (W.I.) Contrast ratio (C.R.) Washability cycles
1. 94.205 0.92 1047
2. 93.632 0.92 1023
3. 93.838 0.92 1029
4. 93.574 0.914 1098
5. 93.632 0.92 1023
6. 93.89 0.92 1073
7. 93.971 0.911 1217
8. 93.994 0.912 1302
From Table 2, it is observed that the waterborne coating compositions prepared in examples 1 to 8 of the present disclosure have whiteness index of more than 90% and contrast ratio of more than 0.9, along with washability cycles of more than 900. Thus, these performance properties of waterborne coating compositions 1 to 8 of the present disclosure are found to be better than the conventionally used expensive coating compositions.
Experiment 3: Comparative study of the waterborne coating composition prepared in accordance with the present disclosure with conventional coating compositions
Table 3: Comparative study waterborne coating composition of present disclosure and conventional coating compositions.
Coating composition W.I. C.R. Washability cycles
Example 2 (present disclosure) 93% 0.92 1023
Market Sample 1 – Distemper 88.4% 0.914 111
Market Sample 2 – Emulsion 88.9% 0.897 148
Market Sample 3 – Emulsion 89.4% 0.93 125 cycles
From Table 3 it is observed that the waterborne coating composition of the present disclosure having more whiteness index, contrast ratio and washability cycles as compared to the conventional coating compositions (market samples 1 to 3).
TECHNICAL ADVANCES AND ECONOMIC SIGNIFICANCE
The present disclosure described hereinabove has several technical advantages including, but not limited to, the realization of a waterborne coating composition that;
• is cheaper;
• has improved whiteness index (W.I.) and improved washability cycles; and
• has significantly improved contrast ratio (C.R.) thereby providing improved opacity;
and,
a process for the preparation of a waterborne coating composition that;
• is simple, efficient and eco-friendly; and
• is feasible on a large/commercial scale.
The embodiments herein and the various features and advantageous details thereof are explained with reference to the non-limiting embodiments in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.
The foregoing description of the specific embodiments so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.
The use of the expression “at least” or “at least one” suggests the use of one or more elements or ingredients or quantities, as the use may be in the embodiment of the invention to achieve one or more of the desired objects or results. While certain embodiments of the inventions have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the inventions. Variations or modifications to the formulation of this invention, within the scope of the invention, may occur to those skilled in the art upon reviewing the disclosure herein. Such variations or modifications are well within the spirit of this invention.
Any discussion of documents, acts, materials, devices, articles or the like that has been included in this specification is solely for the purpose of providing a context for the disclosure. It is not to be taken as an admission that any or all of these matters form a part of the prior art base or were common general knowledge in the field relevant to the disclosure as it existed anywhere before the priority date of this application.
The numerical values given for various physical parameters, dimensions, and quantities are only approximate values and it is envisaged that the values higher than the numerical value assigned to the physical parameters, dimensions, and quantities fall within the scope of the invention unless there is a statement in the specification to the contrary.
While considerable emphasis has been placed herein on the specific features of the preferred embodiment, it will be appreciated that many additional features can be added and that many changes can be made in the preferred embodiment without departing from the principles of the disclosure. These and other changes in the preferred embodiment of the disclosure will be apparent to those skilled in the art from the disclosure herein, whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the disclosure and not as a limitation. ,CLAIMS:WE CLAIM:
1. A waterborne coating composition comprising:
a. a styrene-acrylic co-polymer emulsion having a particle size in the range of 110 nm to 170 nm and a glass transition temperature (Tg) of 20 °C;
b. a styrene-acrylic hollow emulsion having a particle size in the range of 600 nm to 700 nm;
c. a dispersion of nano-silica having a particle size in the range of 8 nm to 15 nm;
d. additives; and
e. water.
2. The composition as claimed in claim 1, wherein
a. said styrene-acrylic co-polymer emulsion is present in an amount in the range of 2 mass% to 10 mass%;
b. said styrene-acrylic hollow emulsion is present in an amount in the range of 5 mass% to 15 mass%;
c. said dispersion of nano-silica is present in an amount in the range of 0.1 mass% to 2 mass%;
d. said additives are present in an amount in the range of 10 mass% to 60 mass%; and
e. q.s. water,
wherein said mass% of each ingredient is with respect to the total mass of said waterborne coating composition.
3. The composition as claimed in claim 1, wherein a mass ratio of said styrene-acrylic co-polymer emulsion to said styrene-acrylic hollow emulsion to said dispersion of nano-silica is in the range of 3:5:1 to 15:25:1.
4. The composition as claimed in claim 1, wherein
• said styrene-acrylic co-polymer emulsion contains a solid content in the range of 40 mass% to 45 mass% with respect to the total mass of said styrene-acrylic co-polymer emulsion;
• said styrene-acrylic hollow emulsion contains a solid content in the range of 30 mass% to 35 mass% with respect to the total mass of said styrene-acrylic hollow emulsion; and
• said dispersion of nano-silica contains a solid content in the range of 29 mass% to 31 mass% with respect to the total mass of said dispersion of nano-silica.
5. The composition as claimed in claim 1, wherein said additive is selected from the group consisting of a dispersing agent, a co-solvent, an extender, a pigment, a biocide, a defoamer and at least one rheology modifier.
6. The coating composition as claimed in claim 5, wherein
• said dispersing agent is selected from ammonium salt of polyacrylic acid and ethoxylated alcohols;
• said co-solvent is ester alcohol;
• said extender is selected from the group consisting of calcium carbonate, talc and sodium magnesium aluminosilicate;
• said pigment is titanium dioxide;
• said biocide is selected from the group consisting of benzimidazole carbamate, 2-n-octyl-4-isothiazolin-3-one and mixture of chlormethyl-/methylisothiazolone and formaldehyde;
• said defoamer is selected from mineral oil-based defoamer and hydrocarbon oil based defoamer; and
• said rheology modifier is selected from hydroxy ethyl cellulose and a hydrophobically modified alkali swellable emulsion; wherein said hydrophobically modified alkali swellable emulsion is polyacarboxylic acid.
7. A process for the preparation of a waterborne coating composition, said process comprising the following steps:
i. mixing predetermined amounts of an extender, a pigment and a dispersing agent, a biocide, a defoamer and at least one rheology modifier in a predetermined amount of water followed by stirring at a first predetermined speed for a first predetermined time period to obtain a mixture; and
ii. sequentially, adding predetermined amounts of a styrene-acrylic co-polymer emulsion, a styrene-acrylic hollow emulsion, a dispersion of nano-silica, and a co-solvent in said mixture under stirring and further maintaining under stirring at a second predetermined speed for a second predetermined time period to obtain said waterborne coating composition.
8. The process as claimed in claim 7, wherein
a. said styrene-acrylic co-polymer emulsion has a particle size in the range of 110 nm to 170 nm and a glass transition temperature (Tg) of 20 °C;
b. said styrene-acrylic hollow emulsion has a particle size in the range of 600 nm to 700 nm; and
c. said dispersion of nano-silica has a particle size in the range of 8 nm to 15 nm.
9. The process as claimed in claim 7, wherein a mass ratio of said styrene-acrylic co-polymer emulsion to said styrene-acrylic hollow emulsion to said dispersion of nano-silica is in the range of 3:5:1 to 15:25:1.
10. The process as claimed in claim 7, wherein
• said styrene-acrylic co-polymer emulsion contains a solid content in the range of 40 mass% to 45 mass% with respect to the total mass of said styrene-acrylic co-polymer emulsion;
• said styrene-acrylic hollow emulsion contains a solid content in the range of 30 mass% to 35 mass% with respect to the total mass of said styrene-acrylic hollow emulsion; and
• said dispersion of nano-silica contains a solid content in the range of 29 mass% to 31 mass% with respect to the total mass of said dispersion of nano-silica.
11. The process as claimed in claim 7, wherein
a. said styrene-acrylic co-polymer emulsion is present in an amount in the range of 2 mass% to 10 mass%;
b. said styrene-acrylic hollow emulsion is present in an amount in the range of 5 mass% to 15 mass%;
c. said dispersion of nano-silica is present in an amount in the range of 0.1 mass% to 2 mass%;
d. said extender is present in an amount in the range of 30 mass% to 50 mass%;
e. said pigment is present in an amount in the range of 0 mass% to 1 mass%;
f. said dispersing agent is present in an amount in the range of 0.2 mass% to 0.6 mass%;
g. said biocide is present in an amount in the range of 0.2 mass% to 0.4 mass%;
h. said co-solvent is present in an amount in the range of 0.2 mass% to 0.4 mass%;
i. said defoamer is present in an amount in the range of 0.15 mass% to 0.3 mass%;
j. said rheology modifier is present in an amount in the range of 0.1 mass% to 2 mass%; and
k. water is present in an amount in the range of 40 mass% to 50 mass%,
wherein said mass% of each ingredient is with respect to the total mass of said waterborne coating composition.
12. The process as claimed in claim 7, wherein
• said extender is selected from the group consisting of calcium carbonate, talc and sodium magnesium aluminosilicate;
• said dispersing agent is selected from ammonium salt of polyacrylic acid and ethoxylated alcohols;
• said co-solvent is ester alcohol;
• said pigment is titanium dioxide;
• said biocide is selected from benzimidazole carbamate, 2-n-octyl-4- isothiazolin-3-one and mixture of chlormethyl-/methylisothiazolone and formaldehyde;
• said defoamer is selected from mineral oil-based defoamer and hydrocarbon oil based defoamer; and
• said rheology modifier is selected from hydroxy ethyl cellulose and hydrophobically modified alkali swellable emulsion; wherein hydrophobically modified alkali swellable emulsion is polyacarboxylic acid.
13. The process as claimed in claim 7, wherein
• said first predetermined speed is in the range of 10 m/s to 25 m/s; and
• said second predetermined speed is in the range of 500 rpm to 3000 rpm.
14. The process as claimed in claim 7, wherein
• said first predetermined time period is in the range of 10 minutes to 50 minutes; and
• said second predetermined time period is in the range of 10 minutes to 50 minutes.
15. The waterborne coating composition as claimed in claim 1 is characterized by having at least one of the following:
• whiteness index in the range of 90% to 95% measured as per ASTM E313-20 method;
• contrast ratio in the range of 0.90 to 0.95 measured as per ASTM D2805-11 method; and

• washability cycles are in the range of 800 to 1300 measured as per IS 15489:2013 method.

Dated this 13th Day of January 2025

_______________________________
MOHAN RAJKUMAR DEWAN, IN/PA – 25
OF R. K. DEWAN & CO.
AUTHORIZED AGENT OF APPLICANT

TO,
THE CONTROLLER OF PATENTS
THE PATENT OFFICE, AT MUMBAI