A decorative acrylic cathodic electrophoretic paint and a method for preparing the same

Abstract

The present application belongs to the technical field of acrylic electrophoretic paint, and particularly relates to a decorative acrylic cathode electrophoretic paint and a preparation method thereof, wherein the raw materials include, in mass parts, cationic acrylic emulsion 50-70 parts, cationic cellulose nanocrystal water dispersion 8-15 parts, nano jade stone powder 5-10 parts, curing agent 10-25 parts, metal pigment powder dispersion A 6-10 parts, metal pigment powder dispersion B 6-10 parts, neutralizing agent 5-10 parts, and water 70-100 parts; the metal pigment powder dispersion A is composed of cationic polyurethane water dispersion, metal pigment powder, non-ionic polymer dispersant, suspending agent, and water; the metal pigment powder dispersion B is composed of synthetic resin, metal pigment powder, cationic polymer dispersant, suspending agent, and water; the decorative acrylic cathode electrophoretic paint of the present application is resistant to sweat corrosion, weathering, salt spray, ethanol, and stable.

Description

Technical Field

[0001] This invention belongs to the field of acrylic electrophoretic coating technology, specifically relating to a decorative acrylic cathodic electrophoretic coating and its preparation method. Background Technology

[0002] Electrophoretic coatings, also known as electrophoretic paints, refer to coatings suitable for electrophoretic coating methods. They are water-based coatings with advantages such as low pollution, environmental friendliness, and high coating efficiency. Electrophoretic coatings can be divided into anodic electrophoretic coatings and cathodic electrophoretic coatings. Cathodic electrophoretic coatings form a film by depositing cationic film-forming substances from the electrophoresis tank onto a cathode device via electrophoresis, followed by curing. Cathodic electrophoretic coatings can solve problems associated with anodic electrophoretic coatings, such as easy electrode corrosion, insufficient film stability, and poor corrosion resistance.

[0003] Cathodic electrophoretic coatings mainly include epoxy electrophoretic coatings and acrylic electrophoretic coatings. Compared with epoxy electrophoretic coatings, acrylic electrophoretic coatings are less prone to yellowing and discoloration, have better weather resistance, a wide variety of colors, and good decorative properties, and are often used as topcoats.

[0004] In existing colored acrylic electrophoretic coatings, the pigments are usually inorganic pigments such as carbon black, titanium dioxide, and permanent red. For example, Chinese patent CN116102944A discloses an energy-saving and environmentally friendly cathodic electrophoretic coating and its preparation method. The electrophoretic coating is composed of the following raw materials in parts by weight: 20-80 parts of base resin, 2-10 parts of co-solvent, 2-10 parts of crosslinking agent, 10-50 parts of pigment paste, 50-200 parts of deionized water, and 10-30 parts of additives. The raw materials of the pigment paste include white pigment paste and black pigment paste. Calculated by mass, the white pigment paste includes 20 parts of amine salt dispersion resin, 25 parts of deionized water, 15 parts of kaolin, 2-5 parts of titanium dioxide, and 5 parts of emulsifier. The black pigment paste includes 20 parts of amine salt dispersion resin, 25 parts of deionized water, 15 parts of kaolin, 2-5 parts of carbon black, and 5 parts of emulsifier. For example, Chinese Patent CN115595009B discloses a ferric ion-resistant, high-weather-resistant, bottom-and-top integrated cathodic electrophoretic paint and its preparation method, including the following steps: mixing epoxy resin, bisphenol A, and polyester polyol, and undergoing a chain extension reaction under the action of a catalyst to obtain a modified epoxy resin; the modified epoxy resin is first mixed with a first crosslinking agent and an amine to undergo an amination reaction, followed by a neutralization reaction and emulsification treatment to obtain emulsion A; polyester acrylic monomer and acrylic resin monomer undergo a heat preservation reaction under the action of an initiator to obtain a modified acrylic resin; the modified acrylic resin is mixed evenly with a light absorber, a light stabilizer, and a second crosslinking agent, and then undergoes a neutralization reaction and emulsification treatment to obtain emulsion B; emulsion A and emulsion B are mixed to obtain a compound emulsion; the compound emulsion is mixed evenly with a color paste and deionized water in a certain proportion to obtain an electrophoretic paint, wherein the color paste is a carbon black paste.

[0005] However, the coating obtained by the above-mentioned technical solutions does not have a metallic effect, and due to the presence of fillers and pigments, it is prone to delamination and sedimentation during storage. In addition, when acrylic electrophoretic coatings are used in products that frequently come into contact with human skin, they also need to have good resistance to sweat corrosion. Therefore, it is of great significance to provide a decorative acrylic cathodic electrophoretic coating that can be used as a cathodic acrylic electrophoretic coating and has good stability and a metallic effect. Summary of the Invention

[0006] The purpose of this invention is to provide a decorative acrylic cathodic electrophoretic coating and its preparation method, so as to solve the problems of poor stability, lack of metallic effect of existing acrylic cathodic electrophoretic coatings, and lack of attention to sweat corrosion resistance.

[0007] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0008] In a first aspect, the present invention provides a decorative acrylic cathodic electrophoretic coating, wherein, by weight, the raw materials include: 50-70 parts of cationic acrylic emulsion, 8-15 parts of cationic cellulose nanocrystal aqueous dispersion, 5-10 parts of nano jade powder, 10-25 parts of curing agent, 6-10 parts of metallic pigment powder dispersion A, 6-10 parts of metallic pigment powder dispersion B, 5-10 parts of neutralizing agent, and 70-100 parts of water;

[0009] The metal pigment powder dispersion A is composed of cationic polyurethane aqueous dispersion, metal pigment powder, nonionic polymer dispersant, suspending agent and water; the metal pigment powder dispersion B is composed of synthetic resin, metal pigment powder, cationic polymer dispersant, suspending agent and water.

[0010] The specific values ​​for the above-mentioned cationic acrylic emulsion in the range of 50-70 parts are, for example, 50 parts, 52 parts, 54 parts, 56 parts, 58 parts, 60 parts, 62 parts, 64 parts, 66 parts, 68 parts, 70 parts, etc.

[0011] The specific values ​​for the above-mentioned 8-15 parts of cationic cellulose nanocrystal aqueous dispersion are, for example, 8 parts, 9 parts, 10 parts, 11 parts, 12 parts, 13 parts, 14 parts, 15 parts, etc.

[0012] The specific values ​​for the above-mentioned 5-10 parts of nano jade powder are, for example, 5 parts, 6 parts, 7 parts, 8 parts, 9 parts, 10 parts, etc.

[0013] The specific values ​​for the above-mentioned curing agent in the range of 10-25 parts are, for example, 10 parts, 12 parts, 14 parts, 16 parts, 18 parts, 20 parts, 22 parts, 24 parts, 25 parts, etc.

[0014] The specific values ​​for the above-mentioned 6-10 parts of metal pigment powder dispersion A are, for example, 6 parts, 7 parts, 8 parts, 9 parts, 10 parts, etc.

[0015] The specific values ​​for the above-mentioned metal pigment powder dispersion B (6-10 parts) are, for example, 6 parts, 7 parts, 8 parts, 9 parts, 10 parts, etc.

[0016] The specific values ​​for the above-mentioned 5-10 parts of neutralizing agent are, for example, 5 parts, 6 parts, 7 parts, 8 parts, 9 parts, 10 parts, etc.

[0017] The specific values ​​in the above 70-100 parts water range are, for example, 70 parts, 75 parts, 80 parts, 85 parts, 90 parts, 95 parts, 100 parts, etc.

[0018] The aforementioned cationic acrylic emulsion is commercially available or can be prepared in-house.

[0019] In some embodiments of the present invention, the commercially available cationic acrylic emulsion is selected from... 2608 2354 and At least one of 2535.

[0020] The cationic cellulose nanocrystals in the above-mentioned cationic cellulose nanocrystal aqueous dispersion have a diameter of 10-20 nm and a length of 100-400 nm.

[0021] In some embodiments of the present invention, the cationic cellulose nanocrystal aqueous dispersion was purchased from Serona Technology Co., Ltd., model: JCA20N.

[0022] The average particle size of the above-mentioned nano jade powder is ≤800nm.

[0023] In some embodiments of the present invention, the average particle size of the nano-jade powder is 500-700 nm.

[0024] The curing agent mentioned above is an aqueous cationic blocked aliphatic isocyanate.

[0025] In some embodiments of the present invention, the aqueous cationic blocked aliphatic isocyanate is Guanzhi BL-8129.

[0026] In some embodiments of the present invention, the metal pigment powder dispersion A, by mass percentage, consists of 15-25% cationic polyurethane aqueous dispersion, 10-15% metal pigment powder, 3-8% nonionic polymer dispersant, 1-5% suspending agent, and the balance being water.

[0027] The specific values ​​of 15-25% of the cationic polyurethane aqueous dispersion in the above-mentioned metal pigment powder dispersion A are, for example, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, etc.

[0028] In the above-mentioned metal pigment powder dispersion A, the specific values ​​of 10-15% metal pigment powder are, for example, 10%, 11%, 12%, 13%, 14%, 15%, etc.

[0029] In the above-mentioned metal pigment powder dispersion A: the specific values ​​of nonionic polymer dispersant 3-8% are, for example, 3%, 4%, 5%, 6%, 7%, 8%, etc.

[0030] In the above-mentioned metal pigment powder dispersion A: the specific values ​​of 1-5% suspending agent are, for example, 1%, 2%, 3%, 4%, 5%, etc.

[0031] In some embodiments of the present invention, the cationic polyurethane aqueous dispersion includes PUD-2517 and / or PUD-1219.

[0032] In the above-mentioned metal pigment powder dispersion A: the chemical composition of the nonionic polymer dispersant is a phenolic derivative.

[0033] In some embodiments of the present invention, the nonionic polymer dispersant is Klein Dispersogen 2774.

[0034] In some embodiments of the present invention, the preparation method of the metal pigment powder dispersion A includes the following steps: mixing cationic polyurethane aqueous dispersion, metal pigment powder, nonionic polymer dispersant, suspending agent and water, and stirring at 300-500 rpm for 20-40 min to mix evenly.

[0035] In some embodiments of the present invention, the metal pigment dispersion B, by mass percentage, consists of 15-25% synthetic resin, 10-15% metal pigment powder, 3-8% cationic polymer dispersant, 1-5% suspending agent, and the balance being water.

[0036] In the above-mentioned metal pigment powder dispersion B, the specific values ​​of 15-25% synthetic resin are, for example, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, etc.

[0037] In the above-mentioned metal pigment powder dispersion B, the specific values ​​of 10-15% metal pigment powder are, for example, 10%, 11%, 12%, 13%, 14%, 15%, etc.

[0038] In the above-mentioned metal pigment powder dispersion B: the specific values ​​of the cationic polymer dispersant 3-8% are, for example, 3%, 4%, 5%, 6%, 7%, 8%, etc.

[0039] In the above-mentioned metal pigment powder dispersion B: the specific values ​​of 1-5% suspending agent are, for example, 1%, 2%, 3%, 4%, 5%, etc.

[0040] In some embodiments of the present invention, the synthetic resin is VariPlus UC W 40.

[0041] In some embodiments of the present invention, the cationic polymer dispersant is BASF Soklan HP20.

[0042] In the above-mentioned metal pigment powder dispersions A and B, the metal pigment powder is selected from at least one of pearl powder, aluminum powder, zinc powder, silver powder, and copper powder.

[0043] In some embodiments of the present invention, the metallic pigment powder is flake-shaped metallic pigment powder.

[0044] In some embodiments of the present invention, the flake diameter of the flake-shaped metallic pigment powder is less than 5 μm.

[0045] In the above-mentioned metal pigment powder dispersions A and B, the suspending agent is an aqueous nanocellulose suspending agent.

[0046] In some embodiments of the present invention, the aqueous nanocellulose suspension was purchased from Guangzhou Fluoride New Materials Technology Co., Ltd.

[0047] In some embodiments of the present invention, the preparation method of the metal pigment powder dispersion B includes the following steps: mixing synthetic resin, metal pigment powder, cationic polymer dispersant, suspending agent and water, and stirring at 300-500 rpm for 20-40 min to mix evenly.

[0048] The neutralizing agent mentioned above includes at least one of formic acid, lactic acid, and acetic acid.

[0049] In some embodiments of the present invention, the neutralizing agent is lactic acid.

[0050] Secondly, the present invention provides a method for preparing the above-mentioned decorative acrylic cathodic electrophoretic coating, comprising the following steps: stirring cationic acrylic emulsion, cationic cellulose nanocrystal aqueous dispersion, nano jade powder, curing agent, metal pigment powder dispersion A, metal pigment powder dispersion B, neutralizing agent and water evenly to obtain the coating.

[0051] Compared with the prior art, the present invention has the following beneficial effects:

[0052] 1. This invention creatively provides a decorative acrylic cathodic electrophoretic coating, which uses cationic acrylic emulsion as the main film-forming substance. By adding cationic cellulose nanocrystal aqueous dispersion, nano jade powder, metal pigment powder dispersion A and metal pigment powder dispersion B, it can be uniformly deposited on the substrate surface. The cationic cellulose nanocrystals and nano jade powder are interspersed in the coating pores to form a dense coating with excellent resistance to sweat corrosion (≥60h), hardness (≥3H), weather resistance (≥2000h), salt spray resistance (≥1000h), and ethanol resistance (≥200h) wiping properties.

[0053] 2. This invention creatively prepares metal pigment dispersion A and metal pigment dispersion B. Metal pigment dispersion A uses a specific cationic polyurethane aqueous dispersion and a nonionic polymer dispersant, which can stabilize the metal pigment powder and allow it to arrange itself orderly along the electric field direction during electrophoretic deposition. Furthermore, the cationic polyurethane aqueous dispersion can crosslink with the curing agent, further optimizing the coating structure and improving the coating performance. Metal pigment dispersion B uses a specific synthetic resin and a cationic polymer dispersant, which can stabilize the metal pigment powder and allow it to arrange itself orderly along the electric field direction during electrophoretic deposition, resulting in a coating film with excellent metallic effect. Detailed Implementation

[0054] To further illustrate the technical means and effects of the present invention, the following describes the technical solution of the present invention in conjunction with preferred embodiments of the present invention. However, the present invention is not limited to the scope of the embodiments.

[0055] Unless otherwise specified, all raw materials used in the following examples and comparative examples are commercially available or prepared by conventional methods in the art.

[0056] The cationic polyurethane aqueous dispersion PUD-2517 was purchased from Shanghai Sisheng Polymer Materials Co., Ltd.

[0057] The cationic polyurethane aqueous dispersion PUD-1219 was purchased from Shanghai Sisheng Polymer Materials Co., Ltd.

[0058] The aqueous cationic blocked aliphatic isocyanate Guanzhi BL-8129 was purchased from Guangzhou Guanzhi New Material Technology Co., Ltd.

[0059] The aluminum flakes have a diameter of 3μm and were purchased from Zhejiang Yamei Nanotechnology Co., Ltd.

[0060] The nonionic polymeric dispersant Klein Dispersogen 2774 was purchased from Shanghai Kaiyin Chemical Co., Ltd.

[0061] The aqueous nanocellulose suspension was purchased from Guangzhou Fluoride New Materials Technology Co., Ltd.

[0062] Synthetic resins The VariPlus UC W 40 was purchased from Guangzhou Haoyi New Material Technology Co., Ltd.

[0063] The cationic polymer dispersant BASF Soklan HP20 was purchased from Nanjing Xinhua Yuan Chemical Co., Ltd.

[0064] The cationic cellulose nanocrystals in the aqueous dispersion have a diameter of 10-20 nm and a length of 100-400 nm. They were purchased from Serona Technology Co., Ltd., model number: JCA20N.

[0065] cationic acrylic emulsion 2608 was purchased from Shanghai Alma Lasers Technology Co., Ltd.

[0066] cationic acrylic emulsion 2535 was purchased from Shanghai Alma Lasers Technology Co., Ltd.

[0067] cationic acrylic emulsion 2354 was purchased from Shanghai Alma Lasers Technology Co., Ltd.

[0068] The nano jade powder has an average particle size of 500-700nm and was purchased from Shanghai Kangbida Technology Industry Co., Ltd.

[0069] Example 1

[0070] This embodiment provides a decorative acrylic cathodic electrophoretic coating, the formulation of which is as follows:

[0071] Formulation A for metallic pigment powder dispersion:

[0072]

[0073]

[0074] The preparation method is as follows: mix cationic polyurethane aqueous dispersion, metallic pigment powder, nonionic polymer dispersant, suspending agent and water, and stir at 400 rpm for 30 min to mix evenly.

[0075] Formulation B of metallic pigment powder dispersion:

[0076]

[0077] The preparation method is as follows: mix synthetic resin, metallic pigment powder, cationic polymer dispersant, suspending agent and water, and stir at 40 rpm for 30 min to mix evenly.

[0078] Decorative acrylic cathodic electrophoretic coating formulation:

[0079]

[0080] The preparation method is as follows: cationic acrylic emulsion, cationic cellulose nanocrystal aqueous dispersion, nano jade powder, curing agent, metal pigment powder dispersion A, metal pigment powder dispersion B, neutralizing agent and water are stirred evenly to obtain the product.

[0081] Example 2

[0082] This embodiment provides a decorative acrylic cathodic electrophoretic coating, the formulation of which is as follows:

[0083] Formulation A for metallic pigment powder dispersion:

[0084]

[0085] The preparation method is as follows: mix cationic polyurethane aqueous dispersion, metallic pigment powder, nonionic polymer dispersant, suspending agent and water, and stir at 400 rpm for 30 min to mix evenly.

[0086] Formulation B of metallic pigment powder dispersion:

[0087]

[0088] The preparation method is as follows: mix synthetic resin, metallic pigment powder, cationic polymer dispersant, suspending agent and water, and stir at 40 rpm for 30 min to mix evenly.

[0089] Decorative acrylic cathodic electrophoretic coating formulation:

[0090]

[0091]

[0092] The cationic acrylic emulsion, cationic cellulose nanocrystal aqueous dispersion, nano jade powder, curing agent, metal pigment powder dispersion A, metal pigment powder dispersion B, neutralizing agent and water are stirred evenly to obtain the final product.

[0093] Example 3

[0094] This embodiment provides a decorative acrylic cathodic electrophoretic coating, the formulation of which is as follows:

[0095] Formulation A for metallic pigment powder dispersion:

[0096]

[0097] The preparation method is as follows: mix cationic polyurethane aqueous dispersion, metallic pigment powder, nonionic polymer dispersant, suspending agent and water, and stir at 400 rpm for 30 min to mix evenly.

[0098] Formulation B of metallic pigment powder dispersion:

[0099]

[0100] The preparation method is as follows: mix synthetic resin, metallic pigment powder, cationic polymer dispersant, suspending agent and water, and stir at 40 rpm for 30 min to mix evenly.

[0101] Decorative acrylic cathodic electrophoretic coating formulation:

[0102]

[0103] The cationic acrylic emulsion, cationic cellulose nanocrystal aqueous dispersion, nano jade powder, curing agent, metal pigment powder dispersion A, metal pigment powder dispersion B, neutralizing agent and water are stirred evenly to obtain the final product.

[0104] Example 4

[0105] This embodiment provides a decorative acrylic cathodic electrophoretic coating, the formulation of which is as follows:

[0106] Formulation A for metallic pigment powder dispersion:

[0107]

[0108]

[0109] The preparation method is as follows: mix cationic polyurethane aqueous dispersion, metallic pigment powder, nonionic polymer dispersant, suspending agent and water, and stir at 400 rpm for 30 min to mix evenly.

[0110] Formulation B of metallic pigment powder dispersion:

[0111]

[0112] The preparation method is as follows: mix synthetic resin, metallic pigment powder, cationic polymer dispersant, suspending agent and water, and stir at 40 rpm for 30 min to mix evenly.

[0113] Decorative acrylic cathodic electrophoretic coating formulation:

[0114]

[0115] The cationic acrylic emulsion, cationic cellulose nanocrystal aqueous dispersion, nano jade powder, curing agent, metal pigment powder dispersion A, metal pigment powder dispersion B, neutralizing agent and water are stirred evenly to obtain the final product.

[0116] Comparative Example 1

[0117] This comparative example provides a decorative acrylic cathodic electrophoretic coating, which differs from Example 3 in that the mass fraction of the cationic cellulose nanocrystal aqueous dispersion is 0 parts, and the mass fraction of the nano jade powder is 0 parts; all other aspects are the same.

[0118] The preparation method is the same as in Example 1.

[0119] Comparative Example 2

[0120] This comparative example provides a decorative acrylic cathodic electrophoretic coating, which differs from Example 3 in that the metal pigment powder dispersion A is replaced with an equal mass of metal pigment powder B; all other aspects are the same.

[0121] The preparation method is the same as in Example 1.

[0122] Comparative Example 3

[0123] This comparative example provides a decorative acrylic cathodic electrophoretic coating, which differs from Example 3 in that the metal pigment powder dispersion B is replaced with an equal mass of metal pigment powder A; all other aspects are the same.

[0124] The preparation method is the same as in Example 1.

[0125] Comparative Example 4

[0126] This comparative example provides a decorative acrylic cathodic electrophoretic coating, which differs from Example 3 in that the cationic polyurethane aqueous dispersion is... 2089 polyurethane dispersion, purchased from Shanghai Alma New Materials Technology Co., Ltd.; all others are the same.

[0127] The preparation method is the same as in Example 1.

[0128] Comparative Example 5

[0129] This comparative example provides a decorative acrylic cathodic electrophoretic coating, which differs from Example 3 in that the cationic polymer dispersant is replaced with an equal mass of 2,3-epoxypropyltrimethylammonium chloride; all other aspects are the same.

[0130] The preparation method is the same as in Example 1.

[0131] Comparative Example 6

[0132] This comparative example provides a decorative acrylic cathodic electrophoretic coating, which differs from Example 3 in that the nonionic polymer dispersant is replaced with a high molecular weight carboxylic acid polymer COADIS. TM BR85 was purchased from Guangzhou Qilang Chemical Co., Ltd.; all other components are identical.

[0133] The preparation method is the same as in Example 1.

[0134] Test Example 1: Stability: The decorative acrylic cathodic electrophoretic coatings of Examples 1-4 and Comparative Examples 1-6 were placed at 25°C for 3 months to observe whether sedimentation occurred. If sedimentation occurred, it was recorded as unqualified.

[0135] Test Example 2: Decorative acrylic cathodic electrophoretic coatings from Examples 1-4 and Comparative Examples 1-6 were diluted with water to a solid content of 10% for electrophoresis. The workpiece was a 304 stainless steel plate. Electrophoresis was performed at 25°C, with a coating thickness of 20 μm, an electrophoresis pressure of 80 V, and an electrophoresis time of 30 s. After electrophoresis, curing was carried out at 140°C for 20 min. The following tests were then conducted:

[0136] Resistance to perspiration corrosion: Refer to ISO 12870-2024;

[0137] Hardness: GB / T6739-2022;

[0138] Adhesion: GB / T9286-2021;

[0139] Weather resistance: GB / T1865-2009;

[0140] Salt spray resistance: ASTM B117-2019;

[0141] Ethanol resistance: Refer to GB / T 23989-2009 (Method A), the reagent is 95% ethanol.

[0142] The test results are as follows:

[0143]

[0144]

[0145] The test data above show that the decorative acrylic cathodic electrophoretic coatings of Examples 1-4 have excellent appearance, resistance to sweat corrosion, hardness, adhesion, weather resistance, salt spray resistance, ethanol resistance and stability.

[0146] As can be seen from Comparative Example 1, cationic cellulose nanocrystal aqueous dispersion and nano jade powder can significantly improve the appearance, sweat corrosion resistance, hardness, weather resistance, salt spray resistance and ethanol resistance of decorative acrylic cathodic electrophoretic coating.

[0147] Comparative Examples 2 and 3 show that metal pigment powder dispersion A and metal pigment powder dispersion B can synergistically improve the appearance, sweat corrosion resistance, weather resistance, salt spray resistance, ethanol resistance and stability of decorative acrylic cathodic electrophoretic coatings.

[0148] As can be seen from Comparative Examples 4-6, the selection of cationic polyurethane aqueous dispersion, cationic polymer dispersant and nonionic polymer dispersant in metal pigment powder dispersion A and metal pigment powder dispersion B is crucial, as it can improve the appearance, adhesion, sweat corrosion resistance, weather resistance, salt spray resistance, ethanol resistance and stability of decorative acrylic cathodic electrophoretic coatings.

[0149] Finally, it should be noted that the above content is only used to illustrate the technical solution of the present invention, and is not intended to limit the scope of protection of the present invention. Simple modifications or equivalent substitutions made by those skilled in the art to the technical solution of the present invention do not depart from the essence and scope of the technical solution of the present invention.

Claims

1. A decorative acrylic cathodic electrophoretic coating, characterized in that, By weight, the raw materials include: 50-70 parts cationic acrylic emulsion, 8-15 parts cationic cellulose nanocrystal aqueous dispersion, 5-10 parts nano jade powder, 10-25 parts curing agent, 6-10 parts metallic pigment powder dispersion A, 6-10 parts metallic pigment powder dispersion B, 5-10 parts neutralizing agent, and 70-100 parts water; The metal pigment powder dispersion A, by mass percentage, consists of 15-25% cationic polyurethane aqueous dispersion, 10-15% metal pigment powder, 3-8% nonionic polymer dispersant, 1-5% suspending agent, and the remainder being water. The chemical composition of the nonionic polymer dispersant is a phenolic derivative; The metal pigment powder dispersion B, by mass percentage, consists of 15-25% synthetic resin, 10-15% metal pigment powder, 3-8% cationic polymer dispersant, 1-5% suspending agent, and the remainder being water. The synthetic resin is TEGO. ® VariPlus UC W 40; The cationic polymer dispersant is BASF Soklan HP20.

2. The decorative acrylic cathodic electrophoretic coating according to claim 1, characterized in that, The cationic cellulose nanocrystals in the aqueous dispersion have a diameter of 10-20 nm and a length of 100-400 nm; the average particle size of the nano-jade powder is ≤800 nm.

3. The decorative acrylic cathodic electrophoretic coating according to claim 2, characterized in that, The cationic polyurethane aqueous dispersion includes PUD-2517 and / or PUD-1219.

4. The decorative acrylic cathodic electrophoretic coating according to claim 3, characterized in that, The metallic pigment powder is selected from at least one of aluminum powder, zinc powder, silver powder, and copper powder.

5. The decorative acrylic cathodic electrophoretic coating according to claim 4, characterized in that, The metallic pigment powder is in the form of flakes; the diameter of the flakes is less than 5µm.

6. The method for preparing the decorative acrylic cathodic electrophoretic coating according to any one of claims 1-5, characterized in that, Includes the following steps: The cationic acrylic emulsion, cationic cellulose nanocrystal aqueous dispersion, nano jade powder, curing agent, metal pigment powder dispersion A, metal pigment powder dispersion B, neutralizing agent and water are stirred evenly to obtain the final product.

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