Coating composition

Abstract

Disclosed is a coating composition comprising a grind resin and a base resin, wherein the grind resin comprises a first acrylic resin comprising moieties derived from glycidyl versatate, the base resin comprises a second acrylic resin comprising moieties derived from glycidyl versatate, and the weight percent of glycidyl versatate moieties in the first acrylic resin is higher than the weight percent of glycidyl versatate moieties in the second acrylic resin. Also disclosed is a substrate coated with the coating composition. Further disclosed is the use of a combination of the grind resin and the base resin for increasing the gloss of a coating in a coating composition.

Description

Technical Field

[0001] This invention relates to the field of coatings, and more specifically to coating compositions with high gloss. Background Technology

[0002] High-gloss coatings are widely used in various fields such as engineering machinery, transportation vehicles, and electronic products. Typically, high-gloss coatings are applied as topcoats to the surface of substrates, providing both protection and aesthetic appeal. Therefore, improving the gloss of coatings has always been a hot research topic in the coatings industry, with both urgent practical needs and potential commercial value. Summary of the Invention

[0003] The inventors have conducted extensive research and developed a coating composition that has improved gloss and is widely applicable to various fields of application.

[0004] The present invention provides a coating composition comprising a grinding resin and a main resin, wherein the grinding resin comprises a first acrylic resin containing a portion derived from glycidyl tert-carbonate, and the main resin comprises a second acrylic resin containing a portion derived from glycidyl tert-carbonate, wherein the weight percentage of the glycidyl tert-carbonate portion in the first acrylic resin is higher than the weight percentage of the glycidyl tert-carbonate portion in the second acrylic resin.

[0005] The present invention also discloses a coated substrate, comprising a substrate and the above-described coating composition coated on at least a portion of the substrate.

[0006] The present invention further discloses the use of a combination of abrasive resin and a main resin for improving the gloss of a coating composition, wherein the abrasive resin comprises a first acrylic resin containing a portion derived from glycidyl tert-carbonate, and the main resin comprises a second acrylic resin containing a portion derived from glycidyl tert-carbonate, wherein the weight percentage of the glycidyl tert-carbonate portion in the first acrylic resin is higher than the weight percentage of the glycidyl tert-carbonate portion in the second acrylic resin.

[0007] The features and advantages of the present invention will be specifically presented in the following detailed description of the embodiments. Detailed Implementation

[0008] As used herein, unless otherwise expressly stated, expressions such as numerical values, ranges, contents, or percentages used in the specification and claims should be considered to vary in all cases according to the term "about," even if the term is not explicitly stated. Therefore, unless stated to the contrary, the numerical parameters listed in the specification and claims herein are approximate values ​​and may vary according to the performance desired by the invention.

[0009] Although the numerical ranges and parameters listed in this invention are approximate, the values ​​listed in the specific embodiments are recorded as accurately as possible. However, any value inherently possesses a certain degree of error. This error is a necessary consequence of the standard deviation derived from the corresponding measurement method.

[0010] Furthermore, it should be understood that any numerical range described herein is intended to include all subranges falling within it. For example, the range “1 to 10” is intended to include all subranges between the minimum value 1 and the maximum value 10, i.e., a minimum value equal to or greater than 1 and a maximum value equal to or less than 10.

[0011] In this application, unless otherwise expressly stated, the use of the singular includes the plural and the plural includes the singular. Furthermore, in this application, unless otherwise expressly stated, "or" is used to mean "and / or," even if "and / or" may be explicitly used in certain circumstances. Additionally, in this application, unless otherwise expressly stated, "a" or "an" is used to mean "at least one." For example, "a" resin, "a" coating, etc., refer to any one or more of these substances. And, as those skilled in the art will recognize, features of one embodiment can be used in conjunction with other embodiments, even if not explicitly stated.

[0012] In this application, the terms “comprising,” “including,” “containing,” and similar terms mean including but not limited to, and do not exclude any variations or additions. Furthermore, although the present invention has described coating compositions and / or methods, etc., using terms such as “comprising,” the coating compositions, etc., detailed herein may also be described as “consisting substantially of” or “consisting of”.

[0013] As described above, the present invention relates to a coating composition comprising a grinding resin and a main resin, wherein the grinding resin comprises a first acrylic resin containing a portion derived from glycidyl tert-carbonate, the main resin comprises a second acrylic resin containing a portion derived from glycidyl tert-carbonate, and the weight percentage of the glycidyl tert-carbonate portion in the first acrylic resin is higher than the weight percentage of the glycidyl tert-carbonate portion in the second acrylic resin.

[0014] As used herein, the term "resin" may be used interchangeably with "polymer" and refers to oligomers and homopolymers, copolymers, and graft polymers. As used herein, the "grinding resin" is premixed with at least a portion of the pigment in the coating composition to coat and / or disperse the pigment before being mixed with the other components of the coating composition. As used herein, the "main resin" provides the mechanical and / or appearance properties of the coating and, together with the grinding resin and curing agent, constitutes the film-forming substance of the coating composition.

[0015] The coating compositions according to the invention can be used as topcoats. As used herein, a topcoat refers to a coating composition used to form the outermost layer of a substrate. Suitably, the coating compositions according to the invention can be used in conjunction with a primer, such as an epoxy primer (i.e., a coating composition in which epoxy resin is the main film-forming substance). Alternatively, the coating compositions according to the invention can be applied directly to a substrate, i.e., the substrate is not coated with any primer / coating composition.

[0016] The coating compositions according to the present invention can be aqueous compositions. As used herein, the term "aqueous" means that the solvent of the coating composition contains at least 50 wt% water based on the weight of the solvent.

[0017] The coating compositions according to the present invention can be two-component compositions. As used herein, the term "two-component," also known as "2K," refers to a coating composition that is cross-linked by reactions between different components and is therefore packaged separately to avoid premature reaction. Typically, the first and second components of a two-component coating composition can be mixed together some time before application to the substrate.

[0018] The coating compositions according to the invention can be thermosetting. As used herein, "thermosetting" means that the coating composition, after being applied to a substrate surface, requires heating to cure into a film. In this document, the term "curing" refers to the process by which a material becomes fixed and no longer flows. Alternatively, the coating compositions according to the invention can be cured at room temperature.

[0019] In the coating composition according to the invention, the abrasive resin comprises a first acrylic resin containing a portion derived from glycidyl tert-carbonate. The first acrylic resin is prepared from a first monomer mixture comprising glycidyl tert-carbonate. In this document, the weight percentage of the glycidyl tert-carbonate portion in the first acrylic resin refers to the weight percentage of the glycidyl tert-carbonate based on the total weight of the first monomer mixture.

[0020] In the coating composition according to the invention, the main resin comprises a second acrylic resin containing a portion derived from glycidyl tert-carbonate. The second acrylic resin is prepared from a second monomer mixture comprising glycidyl tert-carbonate. In this document, the weight percentage of the glycidyl tert-carbonate portion in the second acrylic resin refers to the weight percentage of the glycidyl tert-carbonate based on the total weight of the second monomer mixture.

[0021] Suitably, the amount of glycidyl tert-carbonate may be 25 wt% or higher, such as 25 to 50 wt%, based on the total weight of the first monomer mixture. For example, the amount of glycidyl tert-carbonate may be 25 wt% or higher, 30 wt% or higher, or 35 wt% or higher, and / or 50 wt% or lower, 45 wt% or lower, or 40 wt% or lower, based on the total weight of the first monomer mixture. For example, the amount of glycidyl tert-carbonate may be 25 to 50 wt%, 30 to 45 wt%, 35 to 40 wt%, or within a range ending at any of the above values, based on the total weight of the first monomer mixture.

[0022] Suitably, based on the total weight of the second monomer mixture, the amount of glycidyl tert-carbonate can be less than 25 wt%, such as 5 to less than 25 wt%. For example, based on the total weight of the second monomer mixture, the amount of glycidyl tert-carbonate can be 5 wt% or higher, 10 wt% or higher, or 15 wt% or higher, and / or less than 25 wt% or lower, 23 wt% or lower, or 20 wt% or lower. For example, based on the total weight of the second monomer mixture, the amount of glycidyl tert-carbonate can be 5 to less than 25 wt%, 10 to 23 wt%, 15 to 20 wt%, or within a range ending at any of the above values.

[0023] Suitably, the first monomer mixture may further comprise (1) a (meth)acrylic acid monomer, (2) an aromatic compound monomer containing an unsaturated double bond, and / or (3) an alkyl ester monomer of (meth)acrylic acid. Suitably, the (1) (meth)acrylic acid monomer may comprise acrylic acid, and / or methacrylic acid. Suitably, the (2) aromatic compound monomer containing an unsaturated double bond may comprise styrene, methylstyrene, vinyltoluene, and / or tert-butylstyrene. Suitably, the (3) (meth)acrylic acid alkyl ester monomer may comprise methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, butyl acrylate, butyl methacrylate, tert-butyl acrylate, tert-butyl methacrylate, cyclohexyl methacrylate, cyclohexyl methacrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, glycidyl acrylate, glycidyl methacrylate, isobornyl acrylate, and / or isobornyl methacrylate.

[0024] Suitably, the amount of the (1) (meth)acrylic acid monomer may be from 5 to 20 wt% based on the total weight of the first monomer mixture. For example, the amount of the (1) (meth)acrylic acid monomer may be 5 wt% or higher, 8 wt% or higher, or 10 wt% or higher, and / or 20 wt% or lower, 17 wt% or lower, or 14 wt% or lower based on the total weight of the first monomer mixture. For example, the amount of the (1) (meth)acrylic acid monomer may be from 5 to 20 wt%, 8 to 17 wt%, 10 to 14 wt%, or within a range ending at any of the above values.

[0025] Suitablely, based on the total weight of the first monomer mixture, the amount of the aromatic compound monomer containing unsaturated double bonds in (2) can be from 2 to 15 wt%. For example, based on the total weight of the first monomer mixture, the amount of the aromatic compound monomer containing unsaturated double bonds in (2) can be 2 wt% or higher, 4 wt% or higher, or 6 wt% or higher, and / or 15 wt% or lower, 13 wt% or lower, or 10 wt% or lower. For example, based on the total weight of the first monomer mixture, the amount of the aromatic compound monomer containing unsaturated double bonds in (2) can be from 2 to 15 wt%, 4 to 13 wt%, 6 to 10 wt%, or within a range ending at any of the above values.

[0026] Suitably, the amount of the alkyl ester monomer of (3)(meth)acrylic acid may be 25 to 50 wt% based on the total weight of the first monomer mixture. For example, the amount of the alkyl ester monomer of (3)(meth)acrylic acid may be 25 wt% or higher, 30 wt% or higher, or 35 wt% or higher, and / or 50 wt% or lower, 45 wt% or lower, or 40 wt% or lower based on the total weight of the first monomer mixture. For example, the amount of the alkyl ester monomer of (3)(meth)acrylic acid may be 25 to 50 wt%, 30 to 45 wt%, 35 to 40 wt%, or within a range ending at any of the above values, based on the total weight of the first monomer mixture.

[0027] Suitably, the first monomer mixture may consist of glycidyl tert-carbonate, (1) (meth)acrylic acid monomer, (2) aromatic compound monomer containing an unsaturated double bond, and (3) alkyl ester monomer of (meth)acrylic acid. Suitably, the (1) (meth)acrylic acid monomer may include acrylic acid.

[0028] Suitably, the first acrylic resin may contain hydroxyl groups. Suitably, the first acrylic resin may not contain urethane linking groups. Suitably, the first acrylic resin may not contain carbon-carbon double bonds.

[0029] Suitably, the second monomer mixture may further comprise (1) a (meth)acrylic acid monomer, (2) an aromatic compound monomer containing an unsaturated double bond, and / or (3) an alkyl ester monomer of (meth)acrylic acid. Suitably, the (1) (meth)acrylic acid monomer may comprise acrylic acid, and / or methacrylic acid. Suitably, the (2) aromatic compound monomer containing an unsaturated double bond may comprise styrene, methylstyrene, vinyltoluene, and / or tert-butylstyrene. Suitably, the (3) (meth)acrylic acid alkyl ester monomer may comprise methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, butyl acrylate, butyl methacrylate, tert-butyl acrylate, tert-butyl methacrylate, cyclohexyl methacrylate, cyclohexyl methacrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, glycidyl acrylate, glycidyl methacrylate, isobornyl acrylate, and / or isobornyl methacrylate.

[0030] Suitably, the amount of the (1) (meth)acrylic acid monomer may be 3 to 15 wt% based on the total weight of the second monomer mixture. For example, the amount of the (1) (meth)acrylic acid monomer may be 3 wt% or higher, 5 wt% or higher, or 7 wt% or higher, and / or 15 wt% or lower, 12 wt% or lower, or 10 wt% or lower based on the total weight of the second monomer mixture. For example, the amount of the (1) (meth)acrylic acid monomer may be 3 to 15 wt%, 5 to 12 wt%, 7 to 10 wt%, or within a range ending at any of the above values, based on the total weight of the second monomer mixture.

[0031] Suitablely, based on the total weight of the second monomer mixture, the amount of the aromatic compound monomer containing unsaturated double bonds in (2) can be from 5 to 20 wt%. For example, based on the total weight of the second monomer mixture, the amount of the aromatic compound monomer containing unsaturated double bonds in (2) can be 5 wt% or higher, 7 wt% or higher, or 9 wt% or higher, and / or 20 wt% or lower, 15 wt% or lower, or 13 wt% or lower. For example, based on the total weight of the second monomer mixture, the amount of the aromatic compound monomer containing unsaturated double bonds in (2) can be from 5 to 20 wt%, 7 to 15 wt%, 9 to 13 wt%, or within a range ending at any of the above values.

[0032] Suitably, the amount of the alkyl ester monomer of (3)(meth)acrylic acid may be 35 to 70 wt% based on the total weight of the second monomer mixture. For example, the amount of the alkyl ester monomer of (3)(meth)acrylic acid may be 35 wt% or higher, 40 wt% or higher, or 45 wt% or higher, and / or 70 wt% or lower, 65 wt% or lower, or 55 wt% or lower based on the total weight of the second monomer mixture. For example, the amount of the alkyl ester monomer of (3)(meth)acrylic acid may be 35 to 70 wt%, 40 to 65 wt%, 45 to 55 wt%, or within a range ending at any of the above values, based on the total weight of the second monomer mixture.

[0033] Suitably, the second monomer mixture may consist of glycidyl tert-carbonate, (1) (meth)acrylic acid monomer, (2) aromatic compound monomer containing an unsaturated double bond, and (3) alkyl ester monomer of (meth)acrylic acid. Suitably, the (1) (meth)acrylic acid monomer may include acrylic acid.

[0034] Suitably, the second acrylic resin may contain hydroxyl groups. Suitably, the second acrylic resin may not contain urethane linking groups. Suitably, the second acrylic resin may not contain carbon-carbon double bonds.

[0035] Suitably, the first acrylic resin solid may have an acid value of 15 mg KOH / g or higher, such as 15 to 25 mg KOH / g, or, for example, 20 to 25 mg KOH / g. The first acrylic resin, possessing a hydrophilic monomer (e.g., acrylic acid) and an appropriate acid value, can provide emulsification capabilities for oily curing agents, improving compatibility with components.

[0036] Suitably, the second acrylic resin solid may have an acid value of 15 mg KOH / g or higher, such as 15 to 25 mg KOH / g, or, for example, 20 to 25 mg KOH / g. The first acrylic resin, possessing a hydrophilic monomer (e.g., acrylic acid) and an appropriate acid value, provides emulsification ability for oily curing agents, thereby improving the compatibility between components.

[0037] Suitably, the first acrylic resin may be in the form of an aqueous dispersion. As used herein, the term "aqueous" means that the solvent of the dispersion contains at least 50 wt% water based on the weight of the solvent. The dispersion may have a solids content of 40 to 50 wt%. As used herein, "solids content" refers to the weight percentage of the first acrylic resin solids in the first acrylic resin dispersion.

[0038] Suitably, the second acrylic resin may be in the form of an aqueous dispersion. As used herein, the term "aqueous" means that the solvent of the dispersion contains at least 50 wt% water based on the weight of the solvent. The dispersion may have a solid content of 40 to 50 wt%. As used herein, "solid content" refers to the weight percentage of the second acrylic resin solids in the second acrylic resin dispersion.

[0039] Based on the total weight of the coating composition of the present invention, the total amount of the glycidyl tert-carbonate portion from the first acrylic resin and the glycidyl tert-carbonate portion from the second acrylic resin can be 2 wt% or higher, 4 wt% or higher, or 6 wt% or higher, and / or 15 wt% or lower, 12 wt% or lower, or 10 wt% or lower. Based on the total weight of the coating composition of the present invention, the total amount of the glycidyl tert-carbonate portion from the first acrylic resin and the glycidyl tert-carbonate portion from the second acrylic resin can be 2 to 15 wt%, 4 to 12 wt%, 6 to 10 wt%, or within the range of any of the above values.

[0040] Suitably, the coating composition according to the invention may exclude glycidyl tert-carbonate from the first acrylic resin and the second acrylic resin. That is, the content of the glycidyl tert-carbonate fraction in the coating composition according to the invention may be equal to the sum of the glycidyl tert-carbonate fractions from the first acrylic resin and the second acrylic resin. The coating composition according to the invention may include a glycidyl tert-carbonate fraction of 2 wt% or higher, 4 wt% or higher, or 6 wt% or higher, and / or 15 wt% or lower, 12 wt% or lower, or 10 wt% or lower based on the total weight of the coating composition. The coating composition according to the invention may include a glycidyl tert-carbonate fraction of 2 to 15 wt%, 4 to 12 wt%, 6 to 10 wt%, or within the range ending at any of the above values, based on the total weight of the coating composition. The content of the glycidyl tert-carbonate fraction in the coating composition according to the invention can be obtained by thermal decomposition.

[0041] The coating composition according to the invention further includes pigments. The pigments may include organic pigments and / or inorganic pigments. The pigments may include any pigments suitable for water-based coating compositions.

[0042] In the coating composition according to the invention, at least a portion of the pigment may be pre-mixed with the grinding resin before being mixed with the other components of the coating composition. Suitably, in the coating composition according to the invention, all of the pigment may be pre-mixed with the grinding resin.

[0043] The pigment, along with the grinding resin and optional fillers, additives, and solvents, can be pre-mixed to form a color paste. Suitably, the color paste may comprise an aqueous color paste. As used herein, the term "aqueous" means that the solvent of the color paste contains at least 50 wt% water based on the solvent weight.

[0044] Suitably, the weight ratio of the pigment to the polishing resin can be from 2:1 to 4.5:1. Suitably, the weight ratio of the pigment to the polishing resin can be 2:1 or higher, 2.5:1 or higher, or 3:1 or higher, and / or 4.5:1 or lower, 4:1 or lower, or 3.5:1 or lower. Suitably, the weight ratio of the pigment to the polishing resin can be from 2:1 to 4.5:1, 2.5:1 to 4:1, 3:1 to 3.5:1, or within a range ending at any of the above values.

[0045] In the coating composition according to the invention, the pigment paste is added to the coating composition in an amount satisfying a pigment-to-binder ratio (v / v) of 0.05 to 1. As used herein, the term "pigment-to-binder ratio" refers to the ratio of the volume of pigments and fillers (i.e., pigments and fillers) to the volume of binders (i.e., main resin, polishing resin, and curing agent) in the coating composition. Suitably, the coating composition may have a pigment-to-binder ratio of 0.05 or higher, 0.1 or higher, 0.2 or higher, 0.3 or higher, 0.4 or higher, 0.5 or higher, or 0.6 or higher, and / or 1 or lower, 0.9 or lower, 0.8 or lower, or 0.7 or lower. For example, the coating composition may have a pigment-to-binder ratio of 0.05 to 1, 0.2 to 0.8, 0.5 to 0.7, or within a range ending at any of the above values.

[0046] In the coating composition according to the present invention, a grinding resin comprising the first acrylic resin, a main resin comprising the second acrylic resin, and the pigment may be present in the first component, and the second component may include an isocyanate curing agent. The active hydrogen (e.g., hydroxyl groups) in the first and second acrylic resins of the first component can be crosslinked with the NCO groups in the isocyanate curing agent of the second component through reaction.

[0047] Suitablely, the isocyanate curing agent may include an aqueous isocyanate curing agent and / or an oil-based isocyanate curing agent. The first and second acrylic resins may be compatible with the aqueous isocyanate curing agent, the oil-based isocyanate curing agent, or a mixture thereof. As used herein, the term "oil-based isocyanate curing agent" may also be referred to as "solvent-based isocyanate curing agent." As used herein, the term "aqueous isocyanate curing agent" may be obtained by grafting hydrophilic groups onto a solvent-based isocyanate curing agent.

[0048] The coating compositions according to the invention may further contain other optional ingredients that will not adversely affect the coating composition or the coating thus formed. For example, these optional ingredients may include, but are not limited to, rheology modifiers for adjusting the rheological properties of the coating, improving its resistance to settling during storage and its resistance to sag during application; defoamers and antifoaming agents for inhibiting bubble formation during production and for escaping or breaking existing bubbles; anti-pinhole agents for increasing the surface tension of the coating and eliminating pinholes; fragrances for providing a pleasant odor to the coating; preservatives for protecting the coating from mold; pH adjusters for controlling and stabilizing the coating; waxes for improving scratch resistance and tactile feel; thickeners for increasing coating viscosity and improving wet film thickness and protecting the coating from settling and stratification, etc. Each optional ingredient is preferably included in an amount sufficient to achieve its intended purpose, but not in an amount that adversely affects the coating composition or the coating thus formed.

[0049] The present invention also relates to a coated substrate, comprising a substrate and a coating composition as described above coated on at least a portion of the substrate. Suitably, the substrate may comprise steel and / or tin. For example, the substrate may comprise a steel plate, a tin plate, and / or a tin-plated plate. Suitably, the substrate may comprise a coated substrate. For example, the substrate may comprise a substrate coated with an epoxy primer. Alternatively, the substrate may comprise an uncoated substrate.

[0050] The coating composition according to the invention can be applied by any standard method known in the art, such as spraying, dipping, rolling, brushing, etc., and then cured under heat to form a coating. Typically, the coating composition according to the invention can be cured within 30 minutes at a temperature of 80°C. Alternatively, the coating composition according to the invention can be cured at room temperature. The coating formed by the coating composition according to the invention can have a dry film thickness of 40 to 80 μm.

[0051] The coating formed by the coating composition according to the invention may include a glycidyl tert-carbonate portion. Suitably, based on the total weight of the cured coating formed by the coating composition, the content of the glycidyl tert-carbonate portion may be 5 to 30 wt%, for example 10 to 30 wt%, such as 15 to 30 wt%.

[0052] This invention also relates to the use of a combination of abrasive resin and a main resin in a coating composition for improving the gloss of a coating, wherein the abrasive resin comprises a first acrylic resin containing a portion derived from glycidyl tert-carbonate, and the main resin comprises a second acrylic resin containing a portion derived from glycidyl tert-carbonate, wherein the weight percentage of the glycidyl tert-carbonate portion in the first acrylic resin is higher than the weight percentage of the glycidyl tert-carbonate portion in the second acrylic resin. The first acrylic resin may have the characteristics described above. The second acrylic resin may have the characteristics described above.

[0053] The combination of a polishing resin containing the first acrylic resin and a base resin containing the second acrylic resin can provide improved gloss, resulting in a coating with higher gloss compared to other polishing resins and base resins.

[0054] Suitablely, the coating composition may include an isocyanate curing agent. The isocyanate curing agent may include an aqueous isocyanate curing agent and / or an oil-based isocyanate curing agent.

[0055] Example

[0056] The following embodiments further illustrate the invention, but should not be construed as limiting the invention to the details described in the embodiments. Unless otherwise stated, all parts and percentages in the following embodiments are by weight.

[0057] Example 1

[0058] Preparation of the first acrylic resin dispersion

[0059] In a four-necked flask supplied with N2 and connected to a thermocouple, disperser, and condenser, 46.58 g of propylene glycol butyl ether and 120.96 g of glycidyl tert-carbonate were added sequentially. The mixture was stirred and heated to 150°C, and held at this temperature for 15 min. Then, a mixture consisting of 44.62 g of acrylic acid, 40.81 g of hydroxypropyl methacrylate, 76.11 g of methyl methacrylate, 31.25 g of styrene, 18.99 g of 2-ethylhexyl acrylate, and 2.35 g of tert-butyl peroxide was added dropwise over 3 hours, followed by holding at this temperature for 30 min. Next, a mixture consisting of 0.67 g of tert-butyl peroxide and 1.6 g of propylene glycol butyl ether was added dropwise over 30 min, followed by holding at this temperature for 30 min. The temperature was then lowered to 120°C, and a mixture consisting of 1.6 g of propylene glycol butyl ether and 7.97 g of dimethylaminoethanol was added, and the mixture was held at this temperature for 30 min. The temperature was further reduced to 100℃, 402g of deionized water was added, and the mixture was dispersed at high speed for 60 minutes before being discharged. The final product was a hydroxyl acrylic resin dispersion with a glycidyl tert-carbonate content of 36.35wt% (as a percentage of resin solids) and a solid content of 42.0wt%.

[0060] Example 2

[0061] Preparation of the second acrylic resin dispersion

[0062] In a four-necked flask supplied with N2 and connected to a thermocouple, disperser, and condenser, 46.58 g of propylene glycol butyl ether and 60.48 g of glycidyl tert-carbonate were added sequentially. The mixture was stirred and heated to 150°C, and held at this temperature for 15 min. Then, a mixture consisting of 25.57 g of acrylic acid, 65.60 g of hydroxypropyl methacrylate, 110.24 g of methyl methacrylate, 36.75 g of styrene, 18.68 g of 2-ethylhexyl acrylate, 18.68 g of butyl acrylate, and 2.35 g of tert-butyl peroxide was added dropwise to the flask over 3 hours, followed by holding at the temperature for 30 min. Next, a mixture consisting of 0.67 g of tert-butyl peroxide and 1.6 g of propylene glycol butyl ether was added dropwise over 30 min, followed by holding at the temperature for another 30 min. The temperature was then lowered to 120°C, and a mixture of 1.6 g propylene glycol butyl ether and 8.02 g dimethylaminoethanol was added. The mixture was kept at this temperature for 30 minutes. The temperature was then further lowered to 100°C, and 406.8 g deionized water was added. The mixture was dispersed at high speed for 60 minutes before being discharged. The final product was a hydroxyl acrylic resin dispersion with a glycidyl tert-carbonate content of 18.0 wt% (as a percentage of resin solids) and a solid content of 42.0 wt%.

[0063] Examples 3-7

[0064] Preparation and performance evaluation of waterborne two-component polyurethane yellow topcoat containing hydrophilic modified IPDI trimer (waterborne) and HDI trimer (oilborne).

[0065] Using the hydroxyl acrylic resin dispersions with varying glycidyl tert-carbonate content prepared in Examples 1-2, and acrylic resins (non-E-10P resins) without glycidyl tert-carbonate, a water-based two-component polyurethane yellow topcoat was prepared according to the components and contents listed in Table 1. Specifically, the preparation method includes:

[0066] Preparation of the pigment paste: Add deionized water to the paint mixing tank, fix it under a high-speed disperser, and start stirring at 300-400 rpm / min. Add the dispersant, grinding resin, solvent 1, defoamer 1, neutralizer 1, and rheology modifier to the paint mixing tank sequentially. After adding all the ingredients, maintain the stirring speed for 10 minutes. Adjust the speed to 800-1000 rpm / min, and then slowly add titanium dioxide, iron oxide yellow, pigment yellow 139, and barium sulfate sequentially. After adding all the ingredients, maintain the stirring speed for 15-30 minutes. Then transfer the material from the paint mixing tank to the grinding tank, connect the grinding tank to the circulating cooling water system, and fix it under a high-speed disperser. Start stirring at 1000-1500 rpm / min. Then slowly add 0.7-1.2 times the mass of the material (using abrasive beads) to the grinding tank, increase the stirring speed to 2000-3000 rpm / min, and grind and disperse for 2-3 hours until the pigment paste fineness is less than 20 μm. Pour out the material from the grinding tank and filter out the abrasive beads; the resulting color paste should be stored for later use.

[0067] Preparation of the first component: Add the color paste to the paint mixing tank, fix it under a high-speed disperser, and start stirring at a speed of 300-400 rpm / min. Then add the main resin to the paint mixing tank, maintaining the speed constant, and disperse for 10 minutes. Next, add neutralizer 2, solvent 2, solvent 3, solvent 4, defoamer 2, wetting agent, defoamer 3, and deionized water to the paint mixing tank in sequence, then stir to 600-1000 rpm / min and disperse for 15-20 minutes. Discharge the material to obtain the first component, and store it for later use.

[0068] Preparation of the second component: Add HDI trimer, hydrophilic modified IPDI trimer and solvent 5 sequentially to the paint mixing tank, fix it under a high-speed disperser, start stirring at 500-1000 rpm / min for 20-30 minutes. Discharge the material to obtain the second component, and store it for later use.

[0069] The first and second components were mixed, and a certain amount of water was added to adjust the viscosity so that the viscosity of Tu#4 was 50s. The prepared coating composition was sprayed onto the substrate and then baked to obtain a cured coating. The specific spraying and baking parameters are as follows: the construction environment temperature was maintained at 23℃ and the humidity at 50-60%RH. The coating was sprayed onto the steel plate substrate using an air spray gun, and the final coating thickness was controlled at 40-50μm. After spraying, it was flash-dried at room temperature for 20 minutes, and then baked at 80℃ for 30 minutes.

[0070] Table 1

[0071]

[0072]

[0073] 1 The gloss level of the cured coating at 20° was measured using a BYK gloss meter.2 Determined according to ASTM-D3359 standard; and 3 Determined according to GB / T1732-2020 standard.

[0074] As can be seen from Table 1, using acrylic resin with a high content of glycidyl tert-carbonate as the grinding resin and acrylic resin with a low content of glycidyl tert-carbonate as the main resin results in a final coating with a significantly higher 20° gloss than other combinations.

[0075] Examples 8-9

[0076] Preparation and performance evaluation of waterborne two-component polyurethane black topcoat containing hydrophilic modified IPDI trimer (waterborne) and HDI trimer (oilborne).

[0077] Hydroxyacrylate resin dispersions with varying glycidyl tert-carbonate content prepared in Examples 1-2 were used to prepare a water-based two-component polyurethane black topcoat according to the components and contents listed in Table 2. Specifically, the preparation method includes:

[0078] Preparation of the color paste: Add deionized water to the paint mixing tank, fix it under a high-speed disperser, and start stirring at 300-400 rpm / min. Add the dispersant, grinding resin, solvent 1, defoamer 1, and neutralizer 1 sequentially to the paint mixing tank. After adding all the ingredients, maintain the stirring speed for 10 minutes. Adjust the speed to 800-1000 rpm / min, and then slowly add carbon black sequentially. After adding all the ingredients, maintain the stirring speed for 15-30 minutes. Then transfer the material from the paint mixing tank to the grinding tank, connect the grinding tank to the circulating cooling water system, and fix it under a high-speed disperser. Start stirring at 1000-1500 rpm / min. Then slowly add 0.7-1.2 times the mass of the material (using abrasive beads) to the grinding tank, and increase the stirring speed to 2000-3000 rpm / min. Grind and disperse for 2-3 hours until the color paste fineness is less than 20 μm. Pour out the material from the grinding tank and filter out the abrasive beads; this is the color paste, which can be stored for later use.

[0079] Preparation of the first component: Add the color paste to the paint mixing tank, fix it under a high-speed disperser, and start stirring at a speed of 300-400 rpm / min. Then add the main resin to the paint mixing tank, maintaining the speed constant, and disperse for 10 minutes. Next, add defoamer 2, neutralizer 2, wetting agent, solvent 2, solvent 3, solvent 4, rheology modifier, and deionized water to the paint mixing tank in sequence, then stir to 600-1000 rpm / min and disperse for 15-20 minutes. Discharge the material to obtain the first component, and store it for later use.

[0080] Preparation of the second component: Add HDI trimer, hydrophilic modified IPDI trimer and solvent 5 sequentially to the paint mixing tank, fix it under a high-speed disperser, start stirring at 500-1000 rpm / min for 20-30 minutes. Discharge the material to obtain the second component, and store it for later use.

[0081] The first and second components were mixed, and a certain amount of water was added to adjust the viscosity so that the viscosity of Tu#4 was 50s. The prepared coating composition was sprayed onto the substrate and then baked to obtain a cured coating. The specific spraying and baking parameters are as follows: the construction environment temperature was maintained at 23℃ and the humidity at 50-60%RH. The coating was sprayed onto the steel plate substrate using an air spray gun, and the final coating thickness was controlled at 40-50μm. After spraying, it was flash-dried at room temperature for 20 minutes, and then baked at 80℃ for 30 minutes.

[0082] Table 2

[0083]

[0084]

[0085] 1 The gloss level of the cured coating at 20° was measured using a BYK gloss meter.

[0086] 2 Determined according to ASTM-D3359 standard; and

[0087] 3 Determined according to GB / T1732-2020 standard.

[0088] As can be seen from Table 2, when acrylic resin with a high content of glycidyl tert-carbonate is used as the grinding resin and acrylic resin with a low content of glycidyl tert-carbonate is used as the main resin, the final coating has a higher 20° gloss than other combinations.

[0089] Examples 10-14

[0090] Preparation and gloss evaluation of waterborne two-component polyurethane yellow topcoat containing HDI trimer (oil-based)

[0091] Using the hydroxyl acrylic resin dispersions with varying glycidyl tert-carbonate content prepared in Examples 1-2, and acrylic resins without glycidyl tert-carbonate (non-E-10P resin), a waterborne two-component polyurethane yellow topcoat was prepared according to the components and contents listed in Table 3. Specifically, the preparation method includes:

[0092] Preparation of the pigment paste: Add deionized water to the paint mixing tank, fix it under a high-speed disperser, and start stirring at 300-400 rpm / min. Add the dispersant, grinding resin, solvent 1, defoamer 1, neutralizer 1, and rheology modifier 1 sequentially to the paint mixing tank. After adding all the ingredients, maintain the stirring speed for 10 minutes. Adjust the speed to 800-1000 rpm / min, and then slowly add titanium dioxide, iron oxide yellow, pigment yellow 139, and barium sulfate sequentially. After adding all the ingredients, maintain the stirring speed for 15-30 minutes. Then transfer the material from the paint mixing tank to the grinding tank, connect the grinding tank to the circulating cooling water system, and fix it under a high-speed disperser. Start stirring at 1000-1500 rpm / min. Then slowly add 0.7-1.2 times the mass of the material (using abrasive beads) to the grinding tank, increase the stirring speed to 2000-3000 rpm / min, and grind and disperse for 2-3 hours until the pigment paste fineness is less than 20 μm. Pour out the material from the grinding tank and filter out the abrasive beads; the resulting color paste should be stored for later use.

[0093] Preparation of the first component: Add the color paste to the paint mixing tank, fix it under a high-speed disperser, and start stirring at a speed of 300-400 rpm / min. Then add the main resin to the paint mixing tank, maintaining the speed constant, and disperse for 10 minutes. Next, add defoamer 2, neutralizer 2, neutralizer 3, solvent 2, solvent 3, solvent 4, and rheology modifier 2 to the paint mixing tank in sequence, then stir to 600-1000 rpm / min and disperse for 15-20 minutes. Discharge the material to obtain the first component, and store it for later use.

[0094] Preparation of the second component: Add HDI trimer and solvent 5 sequentially to the paint mixing tank, fix it under a high-speed disperser, start stirring at 500-1000 rpm / min for 20-30 minutes. Discharge the material to obtain the second component, and store it for later use.

[0095] The first and second components were mixed, and a certain amount of water was added to adjust the viscosity so that the viscosity of Tu#4 was 50s. The prepared coating composition was sprayed onto the substrate and then baked to obtain a cured coating. The specific spraying and baking parameters are as follows: the construction environment temperature was maintained at 23℃ and the humidity at 50-60%RH. The coating was sprayed onto the steel plate substrate using an air spray gun, and the final coating thickness was controlled at 40-50μm. After spraying, it was flash-dried at room temperature for 20 minutes, and then baked at 80℃ for 30 minutes.

[0096] Table 3

[0097]

[0098]

[0099]

[0100] 1The gloss level of the cured coating at 20° was measured using a BYK gloss meter.

[0101] 2 Determined according to ASTM-D3359 standard; and

[0102] 3 Determined according to GB / T1732-2020 standard.

[0103] As can be seen from Table 3, when acrylic resin with a high content of glycidyl tert-carbonate is used as the grinding resin and acrylic resin with a low content of glycidyl tert-carbonate is used as the main resin, the final coating has a higher 20° gloss than other combinations.

[0104] Although specific aspects of the invention have been explained and described, it will be apparent to those skilled in the art that many other changes and modifications can be made without departing from the spirit and scope of the invention. Therefore, the appended claims are intended to cover all such changes and modifications that fall within the scope of the invention.

Claims

1. A coating composition comprising a polishing resin and a main resin, wherein the polishing resin comprises a first acrylic resin containing a portion derived from glycidyl tert-carbonate, the main resin comprises a second acrylic resin containing a portion derived from glycidyl tert-carbonate, wherein the weight percentage of the glycidyl tert-carbonate portion in the first acrylic resin is higher than the weight percentage of the glycidyl tert-carbonate portion in the second acrylic resin, the first acrylic resin comprising 25 wt% or more of the glycidyl tert-carbonate portion based on the total solid weight of the first acrylic resin, and the second acrylic resin comprising 5 to less than 25 wt% of the glycidyl tert-carbonate portion based on the total solid weight of the second acrylic resin.

2. The coating composition of claim 1, wherein the first acrylic resin comprises 25 to 50 wt% of glycidyl tert-carbonate based on the total solid weight of the first acrylic resin.

3. The coating composition of claim 1, wherein each of the first acrylic resin and the second acrylic resin does not contain carbon-carbon double bonds.

4. The coating composition of claim 1, wherein the first acrylic resin is prepared from a monomer mixture including (meth)acrylic acid monomer.

5. The coating composition of claim 1, wherein the second acrylic resin is prepared from a monomer mixture comprising (meth)acrylic acid monomer.

6. The coating composition of claim 1, wherein each of the first acrylic resin and the second acrylic resin has an acid value of 15 mgKOH / g or higher.

7. The coating composition of claim 1, wherein the coating composition has a pigment-to-binder ratio (v / v) of 0.05 to 1.

8. The coating composition of claim 1, wherein the coating composition is water-based.

9. The coating composition of claim 1, wherein the coating composition comprises 2 to 15 wt% of glycidyl tert-carbonate based on the total weight of the coating composition.

10. The coating composition of claim 1, wherein the coating composition is a two-component composition, wherein the abrasive resin and the main resin are contained in the first component, and the second component comprises an isocyanate curing agent.

11. The coating composition of claim 10, wherein the isocyanate curing agent comprises an aqueous isocyanate curing agent and / or an oil-based isocyanate curing agent.

12. A coated substrate comprising a substrate and a coating composition as described in any one of claims 1-11 coated on at least a portion of the substrate.

13. The coated substrate of claim 12, wherein the substrate is a steel plate, a tin plate, and / or a tin-plated plate.

14. The coated substrate of claim 12, wherein the coating formed by the coating composition comprises 5 to 30 wt% of glycidyl tert-carbonate based on the total weight of the cured coating.

15. Use of a combination of abrasive resin and a base resin for improving the gloss of a coating composition, wherein the abrasive resin comprises a first acrylic resin containing a portion derived from glycidyl tert-carbonate, the base resin comprises a second acrylic resin containing a portion derived from glycidyl tert-carbonate, wherein the weight percentage of the glycidyl tert-carbonate portion in the first acrylic resin is higher than the weight percentage of the glycidyl tert-carbonate portion in the second acrylic resin, the first acrylic resin comprises 25 wt% or more of the glycidyl tert-carbonate portion based on the total solid weight of the first acrylic resin, and the second acrylic resin comprises 5 to less than 25 wt% of the glycidyl tert-carbonate portion based on the total solid weight of the second acrylic resin.

16. The use as claimed in claim 15, wherein the coating composition comprises an isocyanate curing agent, the isocyanate curing agent comprising an aqueous isocyanate curing agent and / or an oil-based isocyanate curing agent.

17. The use as claimed in claim 15, wherein the first acrylic resin comprises 25 to 50 wt% of glycidyl tert-carbonate fraction based on the total solid weight of the first acrylic resin.

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