Coating composition

Abstract

Disclosed is a coating composition comprising an abrasive resin and a main resin wherein the abrasive resin comprises a first acrylic resin comprising a moiety derived from glycidyl tertiary carboxylic ester and the main resin comprises a second acrylic resin comprising a moiety derived from glycidyl tertiary carboxylic ester, the weight percentage of the glycidyl tertiary carboxylic ester portion in the first acrylic resin is higher than the weight percentage of the glycidyl tertiary carboxylic ester portion in the second acrylic resin. A substrate coated with the coating composition is also disclosed. Also disclosed is the use of a combination of the abrasive resin and the primary resin for improving coating gloss in a coating composition.

Description

Technical Field

[0001] The invention relates to the field of coatings, in particular to a coating composition with high gloss. Background Art

[0002] High gloss coatings are widely used in engineering machinery, transportation vehicles, electronic products and other fields. Usually, high gloss coatings are applied to the surface of substrates as topcoats, which not only play a protective role but also provide aesthetic effects. Therefore, how to improve the gloss of coatings has always been a hot topic in the field of coatings research, with urgent practical needs and potential commercial value. Summary of the invention

[0003] The present inventors have conducted extensive research and developed a coating composition having improved gloss and being widely applicable to various application fields.

[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 versatate glycidyl carbonate, the main resin comprises a second acrylic resin containing a portion derived from versatate glycidyl carbonate, and the weight percentage of the versatate glycidyl carbonate portion in the first acrylic resin is higher than the weight percentage of the versatate glycidyl carbonate portion in the second acrylic resin.

[0005] The invention also discloses a coated substrate, comprising a substrate and the coating composition coated on at least a part of the substrate.

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

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

[0009] Although the numerical ranges and parameters listed for the broad scope of the present invention are approximate, the numerical values ​​listed in the specific examples are recorded as accurately as possible. However, any numerical value inherently has a certain error. The error is the inevitable result of the standard deviation obtained in its corresponding measurement method.

[0010] In addition, it should be understood that any numerical range described herein is intended to include all subranges subsumed therein. For example, a range of "1 to 10" is intended to include all subranges between (and including) the stated minimum value of 1 and the stated maximum value of 10, i.e., having 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. In addition, in this application, unless otherwise expressly stated, the use of "or" means "and / or", even if "and / or" can be explicitly used in some cases. In addition, in this application, unless otherwise expressly stated, the use of "a" or "an" means "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, the features of one embodiment can be used with other embodiments, even if not explicitly stated.

[0012] In this application, "including", "comprising", "containing" and similar terms are meant to include but not limited to, and do not exclude any variants or additions. In addition, although the present invention has described the coating composition and / or method, etc. with terms such as "including", the coating composition, etc. described in detail herein may also be described as "essentially consisting 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 moiety derived from versatate glycidyl carbonate, the main resin comprises a second acrylic resin containing a moiety derived from versatate glycidyl carbonate, and the weight percentage of the versatate glycidyl carbonate moiety in the first acrylic resin is higher than the weight percentage of the versatate glycidyl carbonate moiety in the second acrylic resin.

[0014] As used herein, the term "resin" is used interchangeably with "polymer" to refer to oligomers and homopolymers, copolymers and graft polymers. As used herein, the "grinding resin" is pre-mixed with at least a portion of the pigment of the coating composition to coat and / or disperse the pigment, and then mixed with the other ingredients of the coating composition. As used herein, the "primary resin" provides mechanical and / or appearance properties to the coating, and together with the grinding resin and the curing agent, it constitutes the film-forming substance of the coating composition.

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

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

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

[0018] The coating composition according to the present invention can be cured by heat. As used herein, the "heat curing" refers to the coating composition being cured by heat to form a film after being applied to the substrate surface. In this article, the term "curing" refers to the process of a material becoming fixed and no longer flowing. Alternatively, the coating composition according to the present invention can be cured at room temperature.

[0019] In the coating composition according to the present invention, the grinding resin includes a first acrylic resin, the first acrylic resin contains a portion derived from tert-butyl glycidyl carbonate. The first acrylic resin is prepared from a first monomer mixture including tert-butyl glycidyl carbonate. In this article, the weight percentage of the tert-butyl glycidyl carbonate portion in the first acrylic resin refers to the weight percentage of the weight of tert-butyl glycidyl carbonate based on the total weight of the first monomer mixture.

[0020] In the coating composition according to the present invention, the main resin includes a second acrylic resin, and the second acrylic resin contains a part derived from versatyl glycidyl carbonate. The second acrylic resin is prepared from a second monomer mixture including versatyl glycidyl carbonate. In this article, the weight percentage of the versatyl glycidyl carbonate part in the second acrylic resin refers to the weight percentage of the weight of versatyl glycidyl carbonate based on the total weight of the second monomer mixture.

[0021] Suitably, based on the gross weight of the first monomer mixture, the amount of tert-butyl glycidyl carbonate can be 25wt% or more, such as 25 to 50wt%. For example, based on the gross weight of the first monomer mixture, the amount of tert-butyl glycidyl carbonate can be 25wt% or more, 30wt% or more, or 35wt% or more, and / or 50wt% or less, 45wt% or less, or 40wt% or less. For example, based on the gross weight of the first monomer mixture, the amount of tert-butyl glycidyl carbonate can be 25 to 50wt%, 30 to 45wt%, 35 to 40wt%, or in the range of any of the above values ​​as endpoints.

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

[0023] Suitably, the first monomer mixture may further include (1) (meth) acrylic acid monomers, (2) aromatic compound monomers containing unsaturated double bonds, and / or (3) alkyl ester monomers of (meth) acrylic acid. Suitably, the (1) (meth) acrylic acid monomers may include acrylic acid and / or methacrylic acid. Suitably, the (2) aromatic compound monomers containing unsaturated double bonds may include styrene, methyl styrene, vinyl toluene, and / or tert-butyl styrene. Suitably, the (3) alkyl ester monomers of (meth) acrylic acid may include 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 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 more, 8 wt % or more, or 10 wt % or more, and / or 20 wt % or less, 17 wt % or less, or 14 wt % or less, based on the total weight of the first monomer mixture. For example, the amount of the (1) (meth) acrylic acid monomer may be 5 to 20 wt %, 8 to 17 wt %, 10 to 14 wt %, or within a range with any of the above values ​​as endpoints, based on the total weight of the first monomer mixture.

[0025] Suitably, based on the total weight of the first monomer mixture, the amount of the (2) aromatic compound monomer containing an unsaturated double bond can be 2 to 15 wt %. For example, based on the total weight of the first monomer mixture, the amount of the (2) aromatic compound monomer containing an unsaturated double bond can be 2 wt % or more, 4 wt % or more, or 6 wt % or more, and / or 15 wt % or less, 13 wt % or less, or 10 wt % or less. For example, based on the total weight of the first monomer mixture, the amount of the (2) aromatic compound monomer containing an unsaturated double bond can be 2 to 15 wt %, 4 to 13 wt %, 6 to 10 wt %, or within a range with any of the above values ​​as endpoints.

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

[0027] Suitably, the first monomer mixture may be composed of versatile glycidyl carbonate, (1) (meth) acrylic acid monomer, (2) aromatic compound monomer containing unsaturated double bonds, and (3) (meth) acrylic acid alkyl ester monomer. 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 include (1) (meth) acrylic acid monomers, (2) aromatic compound monomers containing unsaturated double bonds, and / or (3) alkyl ester monomers of (meth) acrylic acid. Suitably, the (1) (meth) acrylic acid monomers may include acrylic acid and / or methacrylic acid. Suitably, the (2) aromatic compound monomers containing unsaturated double bonds may include styrene, methyl styrene, vinyl toluene, and / or tert-butyl styrene. Suitably, the (3) alkyl ester monomers of (meth) acrylic acid may include 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 more, 5 wt % or more, or 7 wt % or more, and / or 15 wt % or less, 12 wt % or less, or 10 wt % or less, 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 with any of the above values ​​as endpoints, based on the total weight of the second monomer mixture.

[0031] Suitably, the amount of the (2) aromatic compound monomer containing an unsaturated double bond can be 5 to 20 wt % based on the total weight of the second monomer mixture. For example, the amount of the (2) aromatic compound monomer containing an unsaturated double bond can be 5 wt % or more, 7 wt % or more, or 9 wt % or more, and / or 20 wt % or less, 15 wt % or less, or 13 wt % or less, based on the total weight of the second monomer mixture. For example, the amount of the (2) aromatic compound monomer containing an unsaturated double bond can be 5 to 20 wt %, 7 to 15 wt %, 9 to 13 wt %, or within a range with any of the above values ​​as endpoints, based on the total weight of the second monomer mixture.

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

[0033] Suitably, the second monomer mixture may be composed of versatile glycidyl carbonate, (1) (meth) acrylic acid monomer, (2) aromatic compound monomer containing unsaturated double bonds, and (3) (meth) acrylic acid alkyl ester monomer. 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 mgKOH / g or higher, such as an acid value of 15 to 25 mgKOH / g, such as an acid value of 20 to 25 mgKOH / g. The first acrylic resin having a hydrophilic monomer (e.g., acrylic acid) and an appropriate acid value may provide emulsification ability to an oily curing agent and improve compatibility with the components.

[0036] Suitably, the second acrylic resin solid may have an acid value of 15 mgKOH / g or higher, such as an acid value of 15 to 25 mgKOH / g, such as an acid value of 20 to 25 mgKOH / g. The first acrylic resin having a hydrophilic monomer (e.g., acrylic acid) and an appropriate acid value provides emulsification ability to the oily curing agent, thereby improving the compatibility between the 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 solid content of 40 to 50 wt%. As used herein, the "solid 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, the "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 versatyl carbonate glycidyl moiety from the first acrylic resin and the versatyl carbonate glycidyl moiety from the second acrylic resin can be 2 wt% or more, 4 wt% or more, or 6 wt% or more, and / or 15 wt% or less, 12 wt% or less, or 10 wt% or less. Based on the total weight of the coating composition of the present invention, the total amount of the versatyl carbonate glycidyl moiety from the first acrylic resin and the versatyl carbonate glycidyl moiety from the second acrylic resin can be 2 to 15 wt%, 4 to 12 wt%, 6 to 10 wt%, or in a range with any of the above values ​​as endpoints.

[0040] Suitably, the coating composition according to the present invention may not include tert-butyl glycidyl carbonate other than the first acrylic resin and the second acrylic resin. That is, the content of the tert-butyl glycidyl carbonate part in the coating composition according to the present invention may be equal to the sum of the tert-butyl glycidyl carbonate part from the first acrylic resin and the tert-butyl glycidyl carbonate part from the second acrylic resin. The coating composition according to the present invention may include 2wt% or more, 4wt% or more, or 6wt% or more, and / or 15wt% or less, 12wt% or less, or 10wt% or less of the tert-butyl glycidyl carbonate part based on the total weight of the coating composition. The coating composition according to the present invention may include 2 to 15wt%, 4 to 12wt%, 6 to 10wt%, or tert-butyl glycidyl carbonate part within the range of any of the above values ​​as endpoints based on the total weight of the coating composition. The content of the tert-butyl glycidyl carbonate part in the coating composition according to the present invention can be obtained by thermal cracking.

[0041] The coating composition according to the present invention also includes a pigment. The pigment may include an organic pigment and / or an inorganic pigment. The pigment may include any pigment suitable for an aqueous coating composition.

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

[0043] The pigment, the grinding resin and the optional fillers, additives and solvents may be premixed to form a color paste. Suitably, the color paste may include 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 weight of the solvent.

[0044] Suitably, the weight ratio of the pigment to the grinding resin may be 2: 1 to 4.5: 1. Suitably, the weight ratio of the pigment to the grinding resin may be 2: 1 or more, 2.5: 1 or more, or 3: 1 or more, and / or 4.5: 1 or less, 4: 1 or less, or 3.5: 1 or less. Suitably, the weight ratio of the pigment to the grinding resin may be 2: 1 to 4.5: 1, 2.5: 1 to 4: 1, 3: 1 to 3.5: 1, or within a range with any of the above values ​​as endpoints.

[0045] In the coating composition according to the present invention, the color paste is added to the coating composition in an amount to satisfy a pigment-to-base ratio (v / v) of 0.05 to 1. As used herein, the term "pigment-to-base ratio" refers to the ratio of the volume of pigments and fillers (i.e., pigments and fillers) to the volume of base materials (i.e., main resin, grinding resin and curing agent) in the coating composition. Suitably, the coating composition may have a pigment-to-base ratio of 0.05 or more, 0.1 or more, 0.2 or more, 0.3 or more, 0.4 or more, 0.5 or more, or 0.6 or more, and / or 1 or less, 0.9 or less, 0.8 or less, or 0.7 or less. For example, the coating composition may have a pigment-to-base ratio of 0.05 to 1, 0.2 to 0.8, 0.5 to 0.7, or within a range with any of the above values ​​as endpoints.

[0046] In the coating composition according to the present invention, the grinding resin including the first acrylic resin, the main resin including 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 group) in the first acrylic resin and the second acrylic resin in the first component and the NCO group in the isocyanate curing agent of the second component may be cross-linked by reaction.

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

[0048] The coating composition according to the present invention may also contain other optional ingredients that do not adversely affect the coating composition or the coating formed therefrom. For example, the optional ingredients may include, but are not limited to, rheological additives for adjusting the rheological properties of the coating, improving the anti-settling during storage and the anti-sagging during construction; anti-foaming agents and defoaming agents for inhibiting the formation of bubbles and escaping or bursting the generated bubbles during the production process; anti-pinhole agents for increasing the surface tension of the coating and eliminating pinholes; fragrances for providing a pleasant smell to the coating; preservatives that can protect the coating from mold; pH regulators that control pH and stabilize the coating; waxes that improve scratch resistance and improve touch; thickeners that increase the viscosity of the coating and improve the wet film thickness and protect the coating from sedimentation 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 formed therefrom.

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

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

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

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

[0053] The combination of a grind resin comprising the first acrylic resin and a main resin comprising the second acrylic resin can provide improved gloss, with the resulting coating having increased gloss compared to other grind resins and main resins.

[0054] Suitably, the coating composition may include an isocyanate curing agent, which may include an aqueous isocyanate curing agent and / or an oily isocyanate curing agent.

[0055] Example

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

[0057] Example 1

[0058] Preparation of the first acrylic resin dispersion

[0059] In a four-necked flask with N2 and connected to a thermocouple, a disperser and a condenser, 46.58g of propylene glycol butyl ether and 120.96g of tert-butyl carbonate were added in sequence, stirring was started and the temperature was raised to 150°C, and the temperature was kept for 15 minutes. Then, a mixture of 44.62g of acrylic acid, 40.81g of hydroxypropyl methacrylate, 76.11g of methyl methacrylate, 31.25g of styrene, 18.99g of 2-ethylhexyl acrylate and 2.35g of tert-butyl peroxyacetate was added dropwise to the four-necked flask, and the mixture was dripped over 3 hours, and then kept warm for 30 minutes. A mixture of 0.67g of tert-butyl peroxyacetate and 1.6g of propylene glycol butyl ether was continued to be dripped, and the mixture was dripped over 30 minutes, and then kept warm for 30 minutes. Then, the temperature was lowered to 120°C and a mixture of 1.6g of propylene glycol butyl ether and 7.97g of dimethylaminoethanol was added, and the temperature was kept warm for 30 minutes. The temperature was further lowered to 100° C., 402 g of deionized water was added, and the mixture was dispersed at high speed for 60 min before discharging. Finally, a hydroxy acrylic resin dispersion having a tert-butyl glycidyl carbonate content of 36.35 wt % (based on the resin solids) and a solid content of 42.0 wt % was obtained.

[0060] Example 2

[0061] Preparation of the Second Acrylic Resin Dispersion

[0062] In a four-necked flask with N2 and connected to a thermocouple, a disperser and a condenser, 46.58g of propylene glycol butyl ether and 60.48g of tert-butyl carbonate were added in sequence, stirring was started and the temperature was raised to 150°C, and the temperature was kept for 15 minutes. Then, a mixture consisting of 25.57g of acrylic acid, 65.60g of hydroxypropyl methacrylate, 110.24g of methyl methacrylate, 36.75g of styrene, 18.68g of 2-ethylhexyl acrylate, 18.68g of butyl acrylate and 2.35g of tert-butyl peroxyacetate was added dropwise to the four-necked flask, and the mixture was dripped over 3 hours, and then kept warm for 30 minutes. A mixture consisting of 0.67g of tert-butyl peroxyacetate and 1.6g of propylene glycol butyl ether was dripped over 30 minutes, and then kept warm for 30 minutes. Then the temperature was lowered to 120°C and a mixture of 1.6 g of propylene glycol butyl ether and 8.02 g of dimethylaminoethanol was added, and the temperature was kept for 30 minutes. The temperature was further lowered to 100°C, 406.8 g of deionized water was added, and the mixture was dispersed at high speed for 60 minutes before discharging. Finally, a hydroxy acrylic resin dispersion having a tert-butyl carbonate content of 18.0 wt% (based on resin solids) and a solid content of 42.0 wt% was obtained.

[0063] Embodiment 3-7

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

[0065] Hydroxylated acrylic resin dispersions with different contents of tert-butyl glycidyl carbonate prepared in Examples 1-2 and acrylic resins without tert-butyl glycidyl carbonate (non-E-10P resin) were used to prepare waterborne two-component polyurethane yellow topcoat according to the ingredients and contents listed in Table 1. Specifically, the preparation method comprises:

[0066] Preparation of color paste: add deionized water to the paint tank, fix it under the high-speed disperser, start stirring, the speed is 300-400rpm / min, and then add dispersant, grinding resin, solvent 1, defoamer 1, neutralizer 1, and rheological additive to the paint tank in turn. After adding, keep the speed unchanged and stir for 10 minutes. Adjust the speed to 800-1000rpm / min, then slowly add titanium dioxide, iron oxide yellow, pigment yellow 139 and barium sulfate in turn, and keep the speed unchanged and stir for 15-30min after adding. Then transfer the materials in the paint tank to the grinding tank, connect the circulating condensed water to the grinding tank and fix it under the high-speed disperser, start stirring at 1000-1500rpm / min, then slowly add 0.7-1.2 times the mass of the material into the grinding tank, stir to 2000-3000rpm / min, grind and disperse for 2-3 hours until the color paste fineness is less than 20μm. Pour out the material in the grinding tank and filter out the pick beads to obtain the color paste, which should be stored for later use.

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

[0068] Preparation of the second component: Add HDI trimer, hydrophilic modified IPDI trimer and solvent 5 into the paint can in sequence, fix it under a high-speed disperser, start stirring at 500-1000rpm / min, and stir for 20-30 minutes. Discharge the material to obtain the second component, which is stored for later use.

[0069] Mix the first and second components, add a certain amount of water to adjust the viscosity, so that the viscosity of Tu#4 is 50s. Spray the prepared coating composition on the substrate, and then bake to obtain a cured coating. The specific spraying and baking parameters are as follows: The construction environment maintains a temperature of 23°C and a humidity of 50-60% RH. Use an air spray gun to spray on the steel plate substrate, and the coating thickness is finally controlled to be 40-50μm. After spraying, flash dry at room temperature for 20 minutes, and then bake at 80°C for 30 minutes.

[0070] Table 1

[0071]

[0072]

[0073] 1 The gloss 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, when acrylic resin with a high content of versatate glycidyl carbonate is used as the grinding resin and acrylic resin with a low content of versatate glycidyl carbonate is used as the main resin, the 20° gloss of the final coating will be significantly higher than that of other combinations.

[0075] Embodiment 8-9

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

[0077] The hydroxylated acrylic resin dispersions with different contents of tert-butyl glycidyl carbonate prepared in Examples 1-2 were used, and water-based two-component polyurethane black topcoat was prepared according to the components and contents listed in Table 2. Specifically, the preparation method comprises:

[0078] Preparation of color paste: add deionized water to the paint tank, fix it under a high-speed disperser, start stirring, the speed is 300-400rpm / min, and add dispersant, grinding resin, solvent 1, defoamer 1, and neutralizer 1 to the paint tank in turn. Keep the speed unchanged and stir for 10 minutes after adding. Adjust the speed to 800-1000rpm / min, then slowly add carbon black in turn, and keep the speed unchanged and stir for 15-30min after adding. Then transfer the materials in the paint tank to the grinding tank, connect the circulating condensed water to the grinding tank and fix it under a high-speed disperser, start stirring at 1000-1500rpm / min, then slowly add 0.7-1.2 times the mass of the material into the grinding tank, stir to 2000-3000rpm / min, grind and disperse for 2-3 hours until the color paste fineness is less than 20μm. Pour out the materials in the grinding tank and filter out the pickaxe beads, which is the color paste, and save it for later use.

[0079] Preparation of the first component: Add the color paste to the paint tank, fix it under the high-speed disperser, start stirring, and the speed is 300-400rpm / min. Then add the main resin to the paint tank, keep the speed unchanged, and disperse for 10 minutes. Then add defoamer 2, neutralizer 2, wetting agent, solvent 2, solvent 3, solvent 4, rheological additive and deionized water to the paint tank in sequence, then stir to 600-1000rpm / min, and disperse for 15-20 minutes. Discharge the material to obtain the first component, which is stored for later use.

[0080] Preparation of the second component: Add HDI trimer, hydrophilic modified IPDI trimer and solvent 5 into the paint can in sequence, fix it under a high-speed disperser, start stirring at 500-1000rpm / min, and stir for 20-30 minutes. Discharge the material to obtain the second component, which is stored for later use.

[0081] Mix the first and second components, add a certain amount of water to adjust the viscosity, so that the viscosity of Tu#4 is 50s. Spray the prepared coating composition on the substrate, and then bake to obtain a cured coating. The specific spraying and baking parameters are as follows: The construction environment maintains a temperature of 23°C and a humidity of 50-60% RH. Use an air spray gun to spray on the steel plate substrate, and the coating thickness is finally controlled to be 40-50μm. After spraying, flash dry at room temperature for 20 minutes, and then bake at 80°C for 30 minutes.

[0082] Table 2

[0083]

[0084]

[0085] 1 The gloss 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 high content of versatate glycidyl carbonate is used as grinding resin and acrylic resin with low content of versatate glycidyl carbonate is used as main resin, the 20° gloss of the final coating is higher than that of other combinations.

[0089] Examples 10-14

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

[0091] Hydroxyl acrylic resin dispersions with different contents of tert-butyl glycidyl carbonate prepared in Examples 1-2 and acrylic resins without tert-butyl glycidyl carbonate (non-E-10P resin) were used to prepare water-based two-component polyurethane yellow topcoat according to the ingredients and contents listed in Table 3. Specifically, the preparation method comprises:

[0092] Preparation of color paste: add deionized water to the paint tank, fix it under the high-speed disperser, start stirring, the speed is 300-400rpm / min, and add dispersant, grinding resin, solvent 1, defoamer 1, neutralizer 1, and rheological additive 1 to the paint tank in turn. Keep the speed unchanged and stir for 10 minutes after adding. Adjust the speed to 800-1000rpm / min, then slowly add titanium dioxide, iron oxide yellow, pigment yellow 139 and barium sulfate in turn, and keep the speed unchanged and stir for 15-30min after adding. Then transfer the materials in the paint tank to the grinding tank, connect the circulating condensed water to the grinding tank and fix it under the high-speed disperser, start stirring at 1000-1500rpm / min, then slowly add 0.7-1.2 times the mass of the material into the grinding tank, stir to 2000-3000rpm / min, grind and disperse for 2-3 hours until the color paste fineness is less than 20μm. Pour out the material in the grinding tank and filter out the pick beads to obtain the color paste, which should be stored for later use.

[0093] Preparation of the first component: Add the color paste to the paint preparation tank, fix it under the high-speed disperser, start stirring, and the speed is 300-400rpm / min. Then add the main resin to the paint preparation tank, keep the speed unchanged, and disperse for 10 minutes. Then add defoamer 2, neutralizer 2, neutralizer 3, solvent 2, solvent 3, solvent 4 and rheological additive 2 to the paint preparation tank in sequence, then stir to 600-1000rpm / min, and disperse for 15-20 minutes. Discharge the material to obtain the first component, which is stored for later use.

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

[0095] Mix the first and second components, add a certain amount of water to adjust the viscosity, so that the viscosity of Tu#4 is 50s. Spray the prepared coating composition on the substrate, and then bake to obtain a cured coating. The specific spraying and baking parameters are as follows: The construction environment maintains a temperature of 23°C and a humidity of 50-60% RH. Use an air spray gun to spray on the steel plate substrate, and the coating thickness is finally controlled to be 40-50μm. After spraying, flash dry at room temperature for 20 minutes, and then bake at 80°C for 30 minutes.

[0096] Table 3

[0097]

[0098]

[0099]

[0100] 1The gloss 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] From Table 3, we can see that when acrylic resin with high content of versatate glycidyl carbonate is used as grinding resin and acrylic resin with low content of versatate glycidyl carbonate is used as main resin, the 20° gloss of the final coating is higher than that of other combinations.

[0104] While particular aspects of the invention have been illustrated and described, it will be apparent to those skilled in the art that various other changes and modifications may be made without departing from the spirit and scope of the invention. It is therefore intended that the appended claims cover all such changes and modifications as fall within the scope of the invention.

Claims

1. A coating composition comprising a grinding resin and a main resin, wherein the grinding resin comprises a first acrylic resin containing a moiety derived from versatate glycidyl carbonate, the main resin comprises a second acrylic resin containing a moiety derived from versatate glycidyl carbonate, the weight percentage of versatate glycidyl carbonate moiety in the first acrylic resin being higher than the weight percentage of versatate glycidyl carbonate moiety in the second acrylic resin.

2. The coating composition of claim 1, wherein the first acrylic resin comprises 25 wt% or more of a versatate glycidyl carbonate moiety based on the total solid weight of the first acrylic resin.

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

4. The coating composition of any one of claims 1 to 3, wherein the second acrylic resin comprises less than 25 wt% of versatate glycidyl carbonate moieties based on the total solid weight of the second acrylic resin.

5. The coating composition of any one of claims 1 to 4, wherein the second acrylic resin comprises 5 to less than 25 wt% of versatate glycidyl carbonate moieties based on the total solid weight of the second acrylic resin.

6. The coating composition of any one of claims 1 to 5, wherein each of the first acrylic resin and the second acrylic resin does not contain a carbon-carbon double bond.

7. The coating composition of any one of claims 1 to 6, wherein the first acrylic resin is prepared from a monomer mixture including a (meth)acrylic acid monomer.

8. The coating composition of any one of claims 1 to 7, wherein the second acrylic resin is prepared from a monomer mixture including a (meth)acrylic acid monomer. 9 . The coating composition according to claim 1 , wherein each of the first acrylic resin and the second acrylic resin has an acid value of 15 mgKOH / g or more.

10. The coating composition of any one of claims 1 to 9, wherein the coating composition has a pigment to binder ratio (v / v) of 0.05 to 1.

11. The coating composition of any one of claims 1-10, wherein the coating composition is water-borne.

12. The coating composition of any one of claims 1-11, wherein the coating composition comprises 2 to 15 wt% of the glycidyl versatate moiety based on the total weight of the coating composition.

13. The coating composition according to any one of claims 1 to 12, wherein the coating composition is a two-component composition, wherein the grinding resin and the main resin are contained in a first component, and a second component comprises an isocyanate-based curing agent.

14. The coating composition according to claim 13, wherein the isocyanate curing agent comprises a water-based isocyanate curing agent and / or an oil-based isocyanate curing agent.

15. A coated substrate comprising a substrate and the coating composition according to any one of claims 1 to 14 coated on at least a portion of the substrate.

16. The coated substrate of claim 15, wherein the substrate comprises steel, and / or tin.

17. A coated substrate as claimed in claim 15 or 16, wherein the coating formed from the coating composition comprises a compound containing a versatate glycidyl carbonate moiety.

18. The coated substrate of any one of claims 15 to 17, wherein the coating formed from the coating composition comprises 5 to 30 wt% of the glycidyl versatate moiety based on the total weight of the cured coating.

19. Use of a combination of a grinding resin and a main resin for improving the gloss of a coating in a coating composition, wherein the grinding resin comprises a first acrylic resin containing a moiety derived from versatate glycidyl carbonate, the main resin comprises a second acrylic resin containing a moiety derived from versatate glycidyl carbonate, the weight percentage of versatate glycidyl carbonate moiety in the first acrylic resin being higher than the weight percentage of versatate glycidyl carbonate moiety in the second acrylic resin.

20. The use according to claim 19, wherein the coating composition comprises an isocyanate curing agent, and the isocyanate curing agent comprises an aqueous isocyanate curing agent and / or an oily isocyanate curing agent.

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