A self-cleaning multicolor paint

Abstract

This application relates to the field of multicolor paint technology, specifically to a self-cleaning multicolor paint. The self-cleaning multicolor paint of this application comprises the following components: deionized water, modified resin, modified nanomaterials, protective colloidal salts, pigments, kaolin, mica powder, titanium dioxide, glass fiber powder, hydroxyethyl cellulose, defoamer, multifunctional additives, dispersing and wetting agents, antifreeze, film-forming aids, and thickeners. The modified nanomaterials and modified resin impart excellent hydrophobic and adhesion properties to the multicolor paint. The preparation method of this self-cleaning multicolor paint includes the following steps: first, a protective sol, a dispersed phase base paint, and a continuous phase clear varnish are prepared separately; then, the protective sol and dispersed phase base paint are mixed and granulated; finally, the sol and continuous phase clear varnish are mixed evenly. The self-cleaning multicolor paint prepared by the above method has rich colors, good simulation effect, and excellent self-cleaning and adhesion properties.

Description

Technical Field

[0001] This application relates to the technical field of multicolor paints, specifically to a self-cleaning multicolor paint. Background Technology

[0002] Multicolor paint is a water-based interior and exterior wall coating processed with special technology. It is usually used to protect and decorate the interior and exterior walls of buildings. It has a rich variety of colors and effects, and can present various simulated effects such as marble, granite, and wood grain, giving the wall surface texture and three-dimensionality. Moreover, multicolor paint generally has excellent properties such as not cracking, not bubbling, scrubbing resistance and mildew resistance, and can maintain its beauty for a long time.

[0003] However, since multicolor paints are often used for the protection and decoration of exterior walls, multicolor paints with self-cleaning functions are becoming increasingly popular and have become a hot topic of research for those skilled in the art.

[0004] The most direct way to obtain multi-color paint with excellent self-cleaning function is to add low surface energy substances, such as fluorosilicone substances or micro-nano particles, to the multi-color paint. However, this direct addition method is prone to delamination, which reduces the adhesion between the low surface energy substances and the wall surface. This not only reduces the self-cleaning performance of the multi-color paint, but also affects the durability of the self-cleaning function. Summary of the Invention

[0005] In order to improve the self-cleaning performance and durability of multicolor paint, this application provides a self-cleaning multicolor paint.

[0006] A self-cleaning multicolor paint comprises the following components in parts by weight: 45-55 parts deionized water, 30-40 parts modified resin, 5-8 parts modified nanomaterials, 2-3.5 parts protective colloidal salt, 0.5-1.5 parts pigment, 1.4-2.1 parts kaolin, 0.3-0.5 parts mica powder, 0.5-1.5 parts titanium dioxide, 0.1-0.3 parts glass fiber powder, 0.5-1 part hydroxyethyl cellulose, 0.2-0.5 parts defoamer, 0.1-0.2 parts multifunctional additive, 0.3-0.6 parts dispersing and wetting agent, 1-2 parts antifreeze, 2-4 parts film-forming aid, and 0.7-1.5 parts thickener;

[0007] The preparation method of the modified nanomaterial includes the following steps:

[0008] S1: Dissolve zinc chloride and sodium hydroxide in deionized water, place at 80℃ for 8-12 hours under sealed conditions, then centrifuge, wash and dry to obtain zinc oxide nanoparticles;

[0009] S2: Dissolve hexadecyltrimethylammonium bromide in deionized water, add methyltrimethoxysilane, stir at room temperature until the solution is clear, then add zinc oxide nanoparticles, stir evenly, then quickly add ammonia water, and stir until a gel is formed; mix methyltrimethylsilane and anhydrous ethanol evenly, slowly add to the gel, let stand at room temperature for 6-12 hours, then dry and grind to obtain modified zinc oxide nanoparticles;

[0010] S4: Mix 3-aminopropyltriethoxysilane and anhydrous ethanol thoroughly, add modified zinc oxide nanoparticles, sonicate for 0.5-1 h, heat to 70℃, stir and reflux for 2-4 h, and distill under reduced pressure to obtain the product.

[0011] In the above technical solution, zinc oxide nanoparticles, as a semiconductor photocatalyst, can effectively photocatalytically degrade organic pollutants adhering to the wall surface, generating small molecules that are easily washed away with water. This gives the multicolor paint coating a certain anti-mildew effect and allows it to maintain a long-lasting self-cleaning function outdoors. However, zinc oxide nanoparticles are prone to agglomeration and have poor dispersibility. Agglomeration reduces their photocatalytic effect and may reduce the self-cleaning effect of the multicolor paint to some extent. Therefore, this application uses a sol-gel method to coat the surface of zinc oxide nanoparticles with silica to improve the dispersibility of zinc oxide nanoparticles. Because the silane precursor contains methyl groups that are not easily soluble in water, silica has good hydrophobic properties, which can further enhance the self-cleaning function of the multicolor paint. Moreover, the silica coating layer also has a three-dimensional network structure with many pores and a large specific surface area, which can improve the strength and toughness of the multicolor paint. In addition, silica has strong activity and is easy to be modified by amination. The modified silica is easier to disperse in the multicolor paint, which improves the bonding strength between silica and modified resin.

[0012] Preferably, the method for preparing the modified resin includes the following steps:

[0013] 1) Dissolve diisocyanate in tetrahydrofuran and isopropanol to obtain mixture a; dissolve aminosilane in tetrahydrofuran and isopropanol to obtain mixture b;

[0014] 2) Under nitrogen protection, slowly add mixture b to mixture a dropwise over a period of 0.5-1 hour. Then add the modified nanomaterials and continue stirring for 4 hours. Add deionized water and remove the solvent by distillation.

[0015] In the above technical solution, isocyanate groups react with primary or secondary amine groups to generate urea-like compounds. Introducing a certain amount of highly polar urea or urethane groups into the modified resin not only improves the adhesion between the modified resin and the substrate, but also allows the urethane or urea groups to form hydrogen bonds. These hydrogen bonds act as physical cross-linking points in the coating, further enhancing the strength of the modified resin. Furthermore, when the coating is damaged under harsh external conditions and cracks form, the flexible polysiloxane fragments can migrate, re-establishing the broken hydrogen bonds and repairing the cracks. Simultaneously, the addition of partially amination-modified nanomaterials allows them to participate in the reaction, chemically linking the nanomaterials to the modified resin. This improves the bonding strength between the modified resin and the nanomaterials, making the nanomaterials less prone to detachment and ensuring the long-lasting self-cleaning properties of the multicolor paint coating.

[0016] In addition, because the modified resin contains polysiloxane soft segments with good hydrophobicity and flexibility, these soft segments tend to accumulate on the coating surface during the multicolor paint film formation process, reducing the surface free energy of the coating, improving the hydrophobicity of the coating, and thus enhancing the self-cleaning function of the coating. Furthermore, because the modified resin also contains highly polar urea or urethane hard segments, these segments tend to accumulate on the substrate surface during the multicolor paint film formation process. They may react chemically with the active groups on the substrate surface or form hydrogen bonds, which not only improves the adhesion between the coating and the substrate, making the coating less prone to peeling off, but also endows the coating with a certain self-healing ability for cracks.

[0017] Preferably, in step S1, the mass ratio of zinc chloride to sodium hydroxide is 1:(0.8-2.2).

[0018] In the above technical solution, the change in the amount of zinc chloride and sodium hydroxide added may have a significant impact on the morphology of the formed zinc oxide nanoparticles. As the morphology of the zinc oxide nanoparticles changes, the specific surface area of ​​the zinc oxide nanoparticles is different, and the photocatalytic effect also changes accordingly. Therefore, in order to improve the photocatalytic activity and specific surface area of ​​zinc oxide nanoparticles, the applicant has restricted the mass ratio of zinc chloride to sodium hydroxide.

[0019] Preferably, in step S2, the mass ratio of methyltrimethoxysilane to zinc oxide nanoparticles is (12.5-20):1.

[0020] In the above technical solution, the mass ratio of methyltrimethoxysilane to zinc oxide nanoparticles should be controlled within a certain range. If the amount of 3-aminopropyltriethoxysilane added is too small, it is not conducive to gel formation, and the generated silica is difficult to grow uniformly on the surface of zinc oxide nanoparticles. As a result, the coating rate of zinc oxide nanoparticles decreases, reducing the hydrophobicity of the modified nanomaterials and negatively affecting the self-cleaning effect of the multicolor paint. If the amount of methyltrimethoxysilane added is too large, the content of zinc oxide nanoparticles decreases, thus reducing the ability of the multicolor paint to degrade organic pollutants. Consequently, it also affects the anti-fouling ability and self-cleaning function of the multicolor paint.

[0021] Preferably, in step S3, the mass ratio of 3-aminopropyltriethoxysilane to modified zinc oxide nanoparticles is (2-5):1.

[0022] In the above technical solution, the mass ratio of 3-aminopropyltriethoxysilane to modified zinc oxide nanoparticles should be controlled within a certain range. If the amount of 3-aminopropyltriethoxysilane added is too small, the amination rate of silica will decrease, which may reduce the reaction rate with isocyanate, reduce the bonding strength between the modified nanomaterial and the modified resin, and reduce the amount of urea groups generated. This will reduce the number of hydrogen bonds to a certain extent, reduce the strength and adhesion of the multicolor paint, and also have an adverse effect on the self-healing properties of the multicolor paint. If the amount of 3-aminopropyltriethoxysilane added is too large, the content of polar groups in the modified resin will be too large, which may reduce the hydrophobicity and increase the hydrophilicity of the multicolor paint, thereby reducing the self-cleaning performance.

[0023] Preferably, in step 1), the diisocyanate is one of isoflurone diisocyanate, hexamethylene diisocyanate, 1,4-cyclohexane dimethyl diisocyanate, and dicyclohexamethane 4,4-diisocyanate; the aminosilane is one of aminopropyl-terminated polydimethylsiloxane, N-β-(aminoethyl)-γ-aminopropylmethyldimethoxysilane, and N-(β-aminoethyl)-γ-aminopropyltrimeth(eth)oxysilane.

[0024] In the above technical solution, isocyanate groups react with primary or secondary amine groups to generate urea compounds. These urea compounds have highly polar urea groups, which may react with groups on the substrate surface, thereby improving the adhesion of the self-cleaning multicolor paint to the substrate. Furthermore, hydrogen bonds can also form between the urea groups, which not only improves adhesion to the substrate but also allows the broken hydrogen bonds to be re-established when cracks appear in the coating, repairing the cracks and giving the self-cleaning multicolor paint a self-healing capability.

[0025] Preferably, in step 1), the mass ratio of the diisocyanate to the aminosilane is 1:(2.4-3.5).

[0026] If the amount of diisocyanate added is too small, the modified resin will contain less urea or urethane groups, thus reducing the adhesion between the modified resin and the substrate, reducing the strength of the multicolor paint, and reducing the self-healing ability of the coating. If the amount of isocyanate compound added is too large, the content of highly polar urea and urethane groups will be higher, reducing the hydrophobicity of the modified resin and thus reducing the self-cleaning performance of the multicolor paint.

[0027] The above-mentioned technical solution of this application includes at least the following beneficial effects:

[0028] 1. In this application, zinc oxide nanoparticles are a semiconductor photocatalyst that can effectively catalyze the degradation of organic matter and play an anti-fouling role. The silica coating on the zinc oxide nanoparticles has a three-dimensional network structure with a large specific surface area and many pores, which not only improves the strength of the multicolor paint, but also the hydrophobicity of the coated silica has a good self-cleaning effect. In addition, in order to make the modified zinc oxide nanoparticles easier to disperse in the modified resin, the modified zinc oxide nanoparticles are subjected to amination treatment, which improves the bonding strength between the nanoparticles and the modified resin.

[0029] 2. In this application, by reacting aminosilane with diisocyanate, urea groups or urethane groups can be introduced into the modified resin. When the coating is damaged or cracked, the movement of the highly compliant organosilicon segments allows the urea groups or urethane groups to come into full contact, forming dynamic and reversible hydrogen bonds, giving the coating material self-healing ability. In addition, the introduction of urea groups or urethane groups increases the adhesion strength between the organosilicon resin and the substrate, giving the coating both good self-cleaning properties and good adhesion.

[0030] 3. The self-cleaning multicolor paint in this application contains modified nanomaterials, titanium dioxide and other micro- and nano-particles, which may cause the coating surface to exhibit good micro- and nano-shaped protrusions, similar to the nipple structure of lotus leaves, making it difficult for water droplets to spread on the coating surface, thus playing a self-cleaning role. Attached Figure Description

[0031] Figure 1 These are trend graphs showing the changes in water contact angle and roll-off angle of the self-cleaning multicolor paint coatings in Examples 1-11 and Comparative Examples 1-3;

[0032] Figure 2 This is a trend graph showing the change in adhesion level of the self-cleaning multicolor paint coatings in Examples 1-11 and Comparative Examples 1-3;

[0033] Figure 3 This is a trend graph showing the change in the stain resistance level of the self-cleaning multicolor paint coatings of Examples 1-11 and Comparative Examples 1-3. Detailed Implementation

[0034] The present application will be further described in detail below with reference to the embodiments.

[0035] Unless otherwise specified, the raw materials used in the embodiments and comparative examples of this application are all commercially available.

[0036] Example

[0037] Example 1

[0038] In this embodiment, the self-cleaning multicolor paint contains the following components in parts by weight: 45 parts deionized water, 30 parts modified resin, 5 parts modified nanomaterials, 2 parts protective colloidal salt, 0.5 parts pigment, 1.4 parts kaolin, 0.3 parts mica powder, 0.5 parts titanium dioxide, 0.1 parts glass fiber powder, 0.5 parts hydroxyethyl cellulose, 0.2 parts defoamer, 0.1 parts multifunctional additive, 0.3 parts dispersing and wetting agent, 1 part antifreeze, 2 parts film-forming aid, and 0.7 parts thickener;

[0039] The preparation method of the modified nanomaterial in this embodiment includes the following steps:

[0040] S1: Weigh 10g of zinc chloride and 12g of sodium hydroxide, dissolve them in 500mL of deionized water, stir evenly, place at 80℃ for 8h under sealed conditions, then centrifuge, wash and dry to obtain zinc oxide nanoparticles.

[0041] S2: Weigh 0.3g of cetyltrimethylammonium bromide and 200mL of deionized water, place them in a flask, stir well, add 40g of methyltrimethoxysilane, stir at room temperature until the solution is clear, then add 4g of zinc oxide nanoparticles, stir well, and then quickly add 5mL of 1mol / L ammonia water, stir until a gel is formed; weigh 10g of methyltrimethylsilane and 10mL of anhydrous ethanol, stir well and slowly add them to the gel, let it stand at room temperature for 6h, then dry and grind to obtain modified zinc oxide nanoparticles;

[0042] S3: Weigh 4g of 3-aminopropyltriethoxysilane and 15mL of anhydrous ethanol, mix thoroughly, add 2g of modified zinc oxide nanoparticles, sonicate for 0.5h, heat to 70℃, stir and reflux for 2h, remove ethanol under reduced pressure to obtain the product.

[0043] The method for preparing the modified resin in this embodiment includes the following steps:

[0044] 1) Weigh 2g of hexamethylene diisocyanate, 10mL of tetrahydrofuran and 10mL of isopropanol, place them in a three-necked flask equipped with a magnetic stirrer, and stir until completely dissolved to obtain mixture a; weigh 7g of N-β-(aminoethyl)-γ-aminopropylmethyldimethoxysilane, 30mL of tetrahydrofuran and 30mL of isopropanol, place them in a beaker and mix well to obtain mixture b;

[0045] 2) Under nitrogen protection, slowly add mixture b to mixture a dropwise over a period of 0.5 h, then add 1.5 g of modified nanomaterials, continue stirring and reacting for 4 h, and remove the solvent by distillation.

[0046] The preparation method of the self-cleaning multicolor paint in this embodiment includes the following steps:

[0047] a. Preparation of protective sol: Add 2 kg of lithium magnesium silicate and 20 kg of deionized water to a disperser and stir until completely dissolved;

[0048] b. Preparation of dispersed phase base paint: Add 0.5 kg of hydroxyethyl cellulose and 8 kg of deionized water to a disperser and stir until dissolved. Then, add 100 g of multifunctional additive, 300 g of dispersing and wetting agent, and 100 g of defoamer in sequence and stir evenly. Then, add 1.4 kg of kaolin, 0.5 kg of titanium dioxide, 0.3 kg of mica powder, and 0.1 kg of glass fiber powder and disperse evenly. Then, add 1 kg of film-forming aid, 0.4 kg of antifreeze agent, and 0.5 kg of pigment and stir evenly.

[0049] c. Preparation of continuous phase varnish: Add 17 kg of deionized water, 30 kg of modified resin, 100 g of defoamer, 1 kg of film-forming aid, and 0.6 kg of antifreeze to a disperser, stir evenly, and then slowly add 0.7 kg of thickener and disperse until uniform.

[0050] d. Preparation of self-cleaning multicolor paint: Mix the prepared dispersed phase base paint with the protective sol, granulate with a multicolor-specific vacuum screen granulator to obtain colored dot particles, then add the continuous phase varnish to the colored dot particles and stir evenly to obtain the final product.

[0051] Example 2

[0052] In this embodiment, the self-cleaning multicolor paint contains the following components in parts by weight: 55 parts deionized water, 40 parts modified resin, 8 parts modified nanomaterials, 3.5 parts protective colloidal salt, 1.5 parts pigment, 2.1 parts kaolin, 0.5 parts mica powder, 1.5 parts titanium dioxide, 0.3 parts glass fiber powder, 1 part hydroxyethyl cellulose, 0.5 parts defoamer, 0.2 parts multifunctional additive, 0.6 parts dispersing and wetting agent, 2 parts antifreeze, 4 parts film-forming aid, and 1.5 parts thickener;

[0053] The preparation method of the modified nanomaterial in this embodiment includes the following steps:

[0054] S1: Weigh 10g of zinc chloride and 12g of sodium hydroxide, dissolve them in 500mL of deionized water, stir well, place at 80℃ for 12h under sealed conditions, then centrifuge, wash and dry to obtain zinc oxide nanoparticles.

[0055] S2: Weigh 0.3g of cetyltrimethylammonium bromide and 200mL of deionized water, place them in a flask, stir well, add 40g of methyltrimethoxysilane, stir at room temperature until the solution is clear, then add 4g of zinc oxide nanoparticles, stir well, and then quickly add 5mL of 1mol / L ammonia water, stir until a gel is formed; weigh 10g of methyltrimethylsilane and 10mL of anhydrous ethanol, stir well and slowly add them to the gel, let it stand at room temperature for 12h, then dry and grind to obtain modified zinc oxide nanoparticles;

[0056] S3: Weigh 4g of 3-aminopropyltriethoxysilane and 15mL of anhydrous ethanol, mix thoroughly, add 2g of modified zinc oxide nanoparticles, sonicate for 1h, heat to 70℃, stir and reflux for 4h, remove ethanol under reduced pressure to obtain the product.

[0057] The method for preparing the modified resin in this embodiment includes the following steps:

[0058] 1) Weigh 2g of 1,4-cyclohexanedimethyl diisocyanate, 10mL of tetrahydrofuran and 10mL of isopropanol, place them in a three-necked flask equipped with a magnetic stirrer, and stir until completely dissolved to obtain mixture a; weigh 7g of N-(β-aminoethyl)-γ-aminopropyltrimeth(eth)oxysilane, 30mL of tetrahydrofuran and 30mL of isopropanol, place them in a beaker and mix well to obtain mixture b;

[0059] 2) Under nitrogen protection, slowly add mixture b to mixture a dropwise over a period of 1 hour. Then add 1.8 g of modified nanomaterials and continue stirring for 4 hours. Remove the solvent by distillation.

[0060] The preparation method of the self-cleaning multicolor paint in this embodiment includes the following steps:

[0061] a. Preparation of protective sol: Add 3.5 kg of lithium magnesium silicate and 25 kg of deionized water to a disperser and stir until completely dissolved;

[0062] b. Preparation of dispersed phase base paint: Add 1 kg of hydroxyethyl cellulose and 10 kg of deionized water to a disperser and stir until dissolved. Then, add 200 g of multifunctional additive, 600 g of dispersing and wetting agent, and 200 g of defoamer in sequence and stir evenly. Then, add 2.1 kg of kaolin, 1.5 kg of titanium dioxide, 0.5 kg of mica powder, and 0.3 kg of glass fiber powder and disperse evenly. Then, add 2 kg of film-forming aid, 1 kg of antifreeze agent, and 1.5 kg of pigment and stir evenly.

[0063] c. Preparation of continuous phase varnish: Add 20 kg of deionized water, 40 kg of modified resin, 300 g of defoamer, 2 kg of film-forming aid, and 1 kg of antifreeze to a disperser, stir evenly, and then slowly add 1.5 kg of thickener and disperse until uniform.

[0064] d. Preparation of self-cleaning multicolor paint: Mix the prepared dispersed phase base paint with the protective sol, granulate with a multicolor-specific vacuum screen granulator to obtain colored dot particles, then add the continuous phase varnish to the colored dot particles and stir evenly to obtain the final product.

[0065] Example 3

[0066] In this embodiment, the self-cleaning multicolor paint contains the following components in parts by weight: 50 parts deionized water, 35 parts modified resin, 7 parts modified nanomaterials, 3 parts protective colloidal salt, 1 part pigment, 1.8 parts kaolin, 0.3 parts mica powder, 1 part titanium dioxide, 0.2 parts glass fiber powder, 0.8 parts hydroxyethyl cellulose, 0.4 parts defoamer, 0.2 parts multifunctional additive, 0.5 parts dispersing and wetting agent, 1.5 parts antifreeze, 3 parts film-forming aid, and 1 part thickener;

[0067] The preparation method of the modified nanomaterial in this embodiment includes the following steps:

[0068] S1: Weigh 10g of zinc chloride and 12g of sodium hydroxide, dissolve them in 500mL of deionized water, stir well, place at 80℃ for 10h under sealed conditions, then centrifuge, wash and dry to obtain zinc oxide nanoparticles.

[0069] S2: Weigh 0.3g of cetyltrimethylammonium bromide and 200mL of deionized water, place them in a flask, stir well, add 40g of methyltrimethoxysilane, stir at room temperature until the solution is clear, then add 4g of zinc oxide nanoparticles, stir well, and then quickly add 5mL of 1mol / L ammonia water, stir until a gel is formed; weigh 10g of methyltrimethylsilane and 10mL of anhydrous ethanol, stir well and slowly add them to the gel, let it stand at room temperature for 9h, then dry and grind to obtain modified zinc oxide nanoparticles;

[0070] S3: Weigh 4g of 3-aminopropyltriethoxysilane and 15mL of anhydrous ethanol, mix thoroughly, add 2g of modified zinc oxide nanoparticles, sonicate for 1h, heat to 70℃, stir and reflux for 4h, remove ethanol under reduced pressure to obtain the product.

[0071] The method for preparing the modified resin in this embodiment includes the following steps:

[0072] 1) Weigh 2g of 4,4-dicyclohexane diisocyanate, 10mL of tetrahydrofuran and 10mL of isopropanol, place them in a three-necked flask equipped with a magnetic stirrer, and stir until completely dissolved to obtain mixture a; weigh 7g of aminopropyl-terminated polydimethylsiloxane, 30mL of tetrahydrofuran and 30mL of isopropanol, place them in a beaker and mix well to obtain mixture b;

[0073] 2) Under nitrogen protection, slowly add mixture b to mixture a dropwise over a period of 1 hour. Then add 1.8 g of modified nanomaterials and continue stirring for 4 hours. Remove the solvent by distillation.

[0074] The preparation method of the self-cleaning multicolor paint in this embodiment includes the following steps:

[0075] a. Preparation of protective sol: Add 3 kg of lithium magnesium silicate and 20 kg of deionized water to a disperser and stir until completely dissolved;

[0076] b. Preparation of dispersed phase base paint: Add 0.8 kg of hydroxyethyl cellulose and 10 kg of deionized water to a disperser and stir until dissolved. Then, add 200 g of multifunctional additive, 500 g of dispersing and wetting agent, and 200 g of defoamer in sequence and stir evenly. Then, add 1.8 kg of kaolin, 1 kg of titanium dioxide, 0.3 kg of mica powder, and 0.2 kg of glass fiber powder and disperse evenly. Then, add 1 kg of film-forming aid, 0.5 kg of antifreeze agent, and 1 kg of pigment and stir evenly.

[0077] c. Preparation of continuous phase varnish: Add 20 kg of deionized water, 35 kg of modified resin, 200 g of defoamer, 2 kg of film-forming aid, and 1 kg of antifreeze to a disperser, stir evenly, and then slowly add 1 kg of thickener and disperse until uniform.

[0078] d. Preparation of self-cleaning multicolor paint: Mix the prepared dispersed phase base paint with the protective sol, granulate with a multicolor-specific vacuum screen granulator to obtain colored dot particles, then add the continuous phase varnish to the colored dot particles and stir evenly to obtain the final product.

[0079] Example 4

[0080] The components of the self-cleaning multicolor paint in this embodiment are the same as those in Example 3;

[0081] The preparation method of the modified nanomaterial in this embodiment differs from that in Example 3 in that:

[0082] S1: Weigh 10g of zinc chloride and 18g of sodium hydroxide, dissolve them in 500mL of deionized water, stir well, place at 80℃ for 10h under sealed conditions, then centrifuge, wash and dry to obtain zinc oxide nanoparticles.

[0083] The remaining steps are the same as in Example 3;

[0084] The preparation method of the modified resin in this embodiment is the same as that in Example 3;

[0085] The preparation method of the self-cleaning multicolor paint in this embodiment is the same as that in Example 3.

[0086] Example 5

[0087] The components of the self-cleaning multicolor paint in this embodiment are the same as those in Example 3;

[0088] The preparation method of the modified nanomaterial in this embodiment differs from that in Example 3 in that:

[0089] S1: Weigh 10g of zinc chloride and 13g of sodium hydroxide, dissolve them in 500mL of deionized water, stir evenly, place at 80℃ for 10h under sealed conditions, then centrifuge, wash and dry to obtain zinc oxide nanoparticles.

[0090] The remaining steps are the same as in Example 3;

[0091] The preparation method of the modified resin in this embodiment is the same as that in Example 3;

[0092] The preparation method of the self-cleaning multicolor paint in this embodiment is the same as that in Example 3.

[0093] Example 6

[0094] The components of the self-cleaning multicolor paint in this embodiment are the same as those in Example 5;

[0095] The preparation method of the modified nanomaterials in this embodiment differs from that in Example 5 in that:

[0096] S2: Weigh 0.3g of cetyltrimethylammonium bromide and 200mL of deionized water, place them in a flask, stir well, add 50g of methyltrimethoxysilane, stir at room temperature until the solution is clear, then add 3g of zinc oxide nanoparticles, stir well, and then quickly add 5mL of 1mol / L ammonia water, stir until a gel is formed; weigh 10g of methyltrimethylsilane and 10mL of anhydrous ethanol, stir well and slowly add them to the gel, let it stand at room temperature for 9h, then dry and grind to obtain modified zinc oxide nanoparticles;

[0097] The remaining steps are the same as in Example 5;

[0098] The preparation method of the modified resin in this embodiment is the same as that in Example 5;

[0099] The preparation method of the self-cleaning multicolor paint in this embodiment is the same as that in Example 5.

[0100] Example 7

[0101] The components of the self-cleaning multicolor paint in this embodiment are the same as those in Example 5;

[0102] The preparation method of the modified nanomaterials in this embodiment differs from that in Example 5 in that:

[0103] S2: Weigh 0.3g of cetyltrimethylammonium bromide and 200mL of deionized water, place them in a flask, stir well, add 40g of methyltrimethoxysilane, stir at room temperature until the solution is clear, then add 3g of zinc oxide nanoparticles, stir well, and then quickly add 5mL of 1mol / L ammonia water, stir until a gel is formed; weigh 5g of methyltrimethylsilane and 10mL of anhydrous ethanol, stir well and slowly add them to the gel, let it stand at room temperature for 9h, then dry and grind to obtain modified zinc oxide nanoparticles;

[0104] The remaining steps are the same as in Example 5;

[0105] The preparation method of the modified resin in this embodiment is the same as that in Example 5;

[0106] The preparation method of the self-cleaning multicolor paint in this embodiment is the same as that in Example 5.

[0107] Example 8

[0108] The components of the self-cleaning multicolor paint in this embodiment are the same as those in Example 7;

[0109] The preparation method of the modified nanomaterial in this embodiment differs from that in Example 7 in that:

[0110] S3: Weigh 14g of 3-aminopropyltriethoxysilane and 15mL of anhydrous ethanol, mix thoroughly, add 2g of modified zinc oxide nanoparticles, sonicate for 1h, heat to 70℃, stir and reflux for 4h, remove ethanol under reduced pressure to obtain the product.

[0111] The remaining steps are the same as in Example 7;

[0112] The preparation method of the modified resin in this embodiment is the same as that in Example 7;

[0113] The preparation method of the self-cleaning multicolor paint in this embodiment is the same as that in Example 7.

[0114] Example 9

[0115] The components of the self-cleaning multicolor paint in this embodiment are the same as those in Example 7;

[0116] The preparation method of the modified nanomaterial in this embodiment differs from that in Example 7 in that:

[0117] S3: Weigh 10g of 3-aminopropyltriethoxysilane and 15mL of anhydrous ethanol, mix thoroughly, add 2g of modified zinc oxide nanoparticles, sonicate for 1h, heat to 70℃, stir and reflux for 4h, remove ethanol under reduced pressure to obtain the product.

[0118] The remaining steps are the same as in Example 7;

[0119] The preparation method of the modified resin in this embodiment is the same as that in Example 7;

[0120] The preparation method of the self-cleaning multicolor paint in this embodiment is the same as that in Example 7.

[0121] Example 10

[0122] The components of the self-cleaning multicolor paint in this embodiment are the same as those in Example 9;

[0123] The preparation method of the modified nanomaterial in this embodiment differs from that in Example 9 in that:

[0124] 1) Weigh 2g of 4,4-dicyclohexane diisocyanate, 10mL of tetrahydrofuran, and 10mL of isopropanol, place them in a three-necked flask equipped with a magnetic stirrer, and stir until completely dissolved to obtain mixture a; weigh 4.8g of aminopropyl-terminated polydimethylsiloxane, 30mL of tetrahydrofuran, and 30mL of isopropanol, place them in a beaker, and mix well to obtain mixture b;

[0125] 2) Under nitrogen protection, slowly add mixture b to mixture a dropwise over a period of 1 hour. Then add 1.36 g of modified nanomaterials and continue stirring for 4 hours. Remove the solvent by distillation.

[0126] The preparation method of the modified resin in this embodiment is the same as that in Example 9;

[0127] The preparation method of the self-cleaning multicolor paint in this embodiment is the same as that in Example 9.

[0128] Example 11

[0129] The components of the self-cleaning multicolor paint in this embodiment are the same as those in Example 9;

[0130] The preparation method of the modified nanomaterial in this embodiment differs from that in Example 9 in that:

[0131] 1) Weigh 2g of 4,4-dicyclohexane diisocyanate, 10mL of tetrahydrofuran and 10mL of isopropanol, place them in a three-necked flask equipped with a magnetic stirrer, and stir until completely dissolved to obtain mixture a; weigh 6g of aminopropyl-terminated polydimethylsiloxane, 30mL of tetrahydrofuran and 30mL of isopropanol, place them in a beaker and mix well to obtain mixture b;

[0132] 2) Under nitrogen protection, slowly add mixture b to mixture a dropwise over a period of 1 hour. Then add 1.6 g of modified nanomaterials and continue stirring for 4 hours. Remove the solvent by distillation.

[0133] The preparation method of the modified resin in this embodiment is the same as that in Example 9;

[0134] The preparation method of the self-cleaning multicolor paint in this embodiment is the same as that in Example 9.

[0135] Comparative Example

[0136] Comparative Example 1

[0137] The self-cleaning multicolor paint in this comparative example contains the following components in parts by weight: 50 parts deionized water, 35 parts modified resin, 1 part pigment, 1.8 parts kaolin, 0.3 parts mica powder, 1 part titanium dioxide, 0.2 parts glass fiber powder, 0.8 parts hydroxyethyl cellulose, 0.4 parts defoamer, 0.2 parts multifunctional additive, 0.5 parts dispersing and wetting agent, 1.5 parts antifreeze, 3 parts film-forming aid, and 1 part thickener;

[0138] The preparation method of the modified resin in this comparative example includes the following steps:

[0139] 1) Weigh 2g of 4,4-dicyclohexane diisocyanate, 10mL of tetrahydrofuran and 10mL of isopropanol, place them in a three-necked flask equipped with a magnetic stirrer, and stir until completely dissolved to obtain mixture a; weigh 7g of aminopropyl-terminated polydimethylsiloxane, 30mL of tetrahydrofuran and 30mL of isopropanol, place them in a beaker and mix well to obtain mixture b;

[0140] 2) Under nitrogen protection, slowly add mixture b to mixture a dropwise over 1 hour, continue stirring for 4 hours, and then remove the solvent by distillation.

[0141] The preparation method of the self-cleaning multicolor paint in this comparative example is the same as that in Example 3.

[0142] Comparative Example 2

[0143] The self-cleaning multicolor paint in this comparative example contains the following components in parts by weight: 50 parts deionized water, 35 parts modified resin, 1 part zinc oxide nanoparticles, 7 parts silica nanoparticles, 1 part pigment, 1.8 parts kaolin, 0.3 parts mica powder, 1 part titanium dioxide, 0.2 parts glass fiber powder, 0.8 parts hydroxyethyl cellulose, 0.4 parts defoamer, 0.2 parts multifunctional additive, 0.5 parts dispersing and wetting agent, 1.5 parts antifreeze, 3 parts film-forming aid, and 1 part thickener;

[0144] The preparation method of the modified resin in this comparative example includes the following steps:

[0145] 1) Weigh 2g of 4,4-dicyclohexane diisocyanate, 10mL of tetrahydrofuran and 10mL of isopropanol, place them in a three-necked flask equipped with a magnetic stirrer, and stir until completely dissolved to obtain mixture a; weigh 7g of aminopropyl-terminated polydimethylsiloxane, 30mL of tetrahydrofuran and 30mL of isopropanol, place them in a beaker and mix well to obtain mixture b;

[0146] 2) Under nitrogen protection, slowly add mixture b to mixture a dropwise over 1 hour. Then add 0.2 g of zinc oxide nanoparticles and 1.6 g of silica particles, continue stirring and reacting for 4 hours, and remove the solvent by distillation.

[0147] The preparation method of the self-cleaning multicolor paint in this comparative example is the same as that in Example 3.

[0148] Comparative Example 3

[0149] The self-cleaning multicolor paint in this comparative example contains the following components in parts by weight: 50 parts deionized water, 35 parts polydimethylsiloxane, 7 parts modified nanomaterials, 3 parts protective colloidal salt, 1 part pigment, 1.8 parts kaolin, 0.3 parts mica powder, 1 part titanium dioxide, 0.2 parts glass fiber powder, 0.8 parts hydroxyethyl cellulose, 0.4 parts defoamer, 0.2 parts multifunctional additive, 0.5 parts dispersing and wetting agent, 1.5 parts antifreeze, 3 parts film-forming aid, and 1 part thickener;

[0150] The preparation method of the modified nanomaterial in this comparative example includes the following steps:

[0151] S1: Weigh 10g of zinc chloride and 12g of sodium hydroxide, dissolve them in 500mL of deionized water, stir well, place at 80℃ for 10h under sealed conditions, then centrifuge, wash and dry to obtain zinc oxide nanoparticles.

[0152] S2: Weigh 0.3g of cetyltrimethylammonium bromide and 200mL of deionized water, place them in a flask, stir well, add 40g of methyltrimethoxysilane, stir at room temperature until the solution is clear, then add 4g of zinc oxide nanoparticles, stir well, and then quickly add 5mL of 1mol / L ammonia water, stir until a gel is formed; weigh 10g of methyltrimethylsilane and 10mL of anhydrous ethanol, stir well and slowly add them to the gel, let it stand at room temperature for 9h, then dry and grind to obtain the final product;

[0153] The preparation method of the self-cleaning multicolor paint in this embodiment includes the following steps:

[0154] a. Preparation of protective sol: Add 3 kg of lithium magnesium silicate and 20 kg of deionized water to a disperser and stir until completely dissolved;

[0155] b. Preparation of dispersed phase base paint: Add 0.8 kg of hydroxyethyl cellulose and 10 kg of deionized water to a disperser and stir until dissolved. Then, add 200 g of multifunctional additive, 500 g of dispersing and wetting agent, and 200 g of defoamer in sequence and stir evenly. Then, add 7 kg of modified nanomaterials, 1.8 kg of kaolin, 1 kg of titanium dioxide, 0.3 kg of mica powder, and 0.2 kg of glass fiber powder and disperse evenly. Then, add 1 kg of film-forming aid, 0.5 kg of antifreeze agent, and 1 kg of pigment and stir evenly.

[0156] c. Preparation of continuous phase varnish: Add 20 kg of deionized water, 35 kg of polydimethylsiloxane, 200 g of defoamer, 2 kg of film-forming aid, and 1 kg of antifreeze to a disperser, stir evenly, and then slowly add 1 kg of thickener and disperse until uniform.

[0157] d. Preparation of self-cleaning multicolor paint: Mix the prepared dispersed phase base paint with the protective sol, granulate with a multicolor-specific vacuum screen granulator to obtain colored dot particles, then add the continuous phase varnish to the colored dot particles and stir evenly to obtain the final product.

[0158] Performance testing

[0159] Detection methods

[0160] The self-cleaning multicolor paints obtained in Examples 1-11 and Comparative Examples 1-3 were applied to asbestos-free cement boards. After drying and forming a film, the following tests were conducted:

[0161] 1. Water contact angle and sliding angle test

[0162] Water contact angle test: At room temperature, a water droplet (2.5 μL) was placed on the coating surface using the pendant drop method. The static contact angle between the water droplet and the sample surface was measured using image analysis technology. The water contact angle was measured 5 times at different locations on each sample coating, and the average value was taken. The test results are shown in the appendix. Figure 1 ;

[0163] Roll-off angle test: Place the coating sample on a horizontal sample stage, then drop water onto the sample surface using a micro-syringe. Gradually and carefully tilt the sample stage. The critical tilt angle of the sample stage when the water droplet rolls off the sample surface is the roll-off angle. Test the roll-off angle 5 times at different positions on each sample coating and take the average value. The test results are shown in the appendix. Figure 1 .

[0164] 2. Adhesion test

[0165] According to GB / T 9286-2021 "Cross-cut Test for Paints and Varnishes", a cross-cut tester is used to make one horizontal and one vertical cut, forming 100 small squares. 3M 600 adhesive tape is then applied to each square, and the tape is quickly pulled off. The coating is graded based on the percentage of area that has detached from the substrate. There are six grades: Grade 1: Smooth cut edges, no detachment at the edges of the squares; Grade 2: Detachment area < 5%; Grade 3: Detachment area 5%-15%; Grade 4: Detachment area 15%-35%; Grade 5: Detachment area 35%-65%; Grade 6: Detachment area > 65%. Test results are attached. Figure 2 .

[0166] 3. Stain resistance test

[0167] The stain resistance of the coating was determined according to GB / T 9870-2013 "Test Method for Stain Resistance of Architectural Coatings". The results were divided into five levels: Level 0: No staining, no perceptible color difference; Level 1: Very slight, barely perceptible color difference; Level 2: Slight, relatively obvious color difference; Level 3: Moderate, very obvious color difference; Level 4: Severe, severe color difference. The test results are attached. Figure 3 .

[0168] Results Analysis

[0169] contrast Figure 1-3 The data from Comparative Examples 1-3 and Examples 1-3 show that modified nanomaterials have a significant impact on the self-cleaning performance of self-cleaning multicolor paints. This may be because the modified nanomaterials themselves have good hydrophobicity and can degrade organic pollutants under photocatalysis. Modified resins can greatly improve the adhesion of self-cleaning multicolor paints, enabling the multicolor paint coating to maintain long-term stability. This may be because the polar groups in the modified resins can undergo physical or chemical reactions with the groups on the substrate surface.

[0170] contrast Figure 1-3 The data from Examples 3-5 show that during the preparation of zinc oxide nanoparticles, as the amount of sodium hydroxide added increases, the water contact angle of the self-cleaning multicolor paint coating increases and the roll-off angle decreases, indicating that the hydrophobicity of the self-cleaning multicolor paint coating is enhanced. This may be because the morphology and structure of zinc oxide nanoparticles also change with the increase of sodium hydroxide addition. With the increase of sodium hydroxide addition, the specific surface area of ​​zinc oxide nanoparticles increases, the photocatalytic efficiency is enhanced, and the anti-fouling property is enhanced.

[0171] contrast Figure 1-3 The data from Examples 5-7 show that during the modification of zinc oxide nanoparticles, as the amount of silane added increases, the water contact angle of the self-cleaning multicolor paint increases, the roll-off angle decreases, the hydrophobicity is enhanced, the self-cleaning performance is improved, and the anti-fouling property is enhanced. This may be because when the amount of silane added increases, the amount of hydrophobic silica on the surface of zinc oxide nanoparticles increases, thus enhancing the hydrophobicity. However, when the amount of silane added is too large, the hydrophobicity of the self-cleaning multicolor paint remains basically unchanged, or even decreases slightly.

[0172] contrast Figure 1-3As can be seen from the data in Examples 7-11, with the increase of polar groups such as urea groups or urethane groups in the modified resin, the adhesion of the self-cleaning multicolor paint is significantly enhanced, and the hydrophobicity is also slightly improved. This may be because the polar groups react chemically with the groups on the substrate surface or form hydrogen bonds, which enhances the adhesion. Moreover, when cracks appear in the coating, urea groups or urethane groups can reform hydrogen bonds to repair the cracks, which also improves the hydrophobicity to a certain extent. However, when there are too many polar groups, the hydrophobicity of the self-cleaning multicolor paint is weakened and the hydrophilicity is enhanced.

[0173] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. A method for preparing a self-cleaning multicolor paint, characterized in that, It comprises the following steps: a. Preparation of protective sol: add magnesium lithium silicate 3 kg and deionized water 20 kg into a disperser and stir until completely dissolved; b. Preparation of dispersed phase base paint: add hydroxyethyl cellulose 0.8 kg and deionized water 10 kg into a disperser and stir until dissolved, then add multifunctional additives 200 g, dispersion wetting agent 500 g, and defoaming agent 200 g in sequence, stir uniformly, then add kaolin 1.8 kg, titanium white 1 kg, mica powder 0.3 kg, and glass fiber powder 0.2 kg, disperse uniformly, then add film forming additives 1 kg, antifreeze 0.5 kg, and pigments 1 kg, and stir uniformly; c. Preparation of continuous phase varnish: add deionized water 20 kg, modified resin 35 kg, defoaming agent 200 g, film forming additives 2 kg, and antifreeze 1 kg into a disperser and stir uniformly, then slowly add thickening agent 1 kg and disperse until uniform; d. Preparation of self-cleaning multi-color paint: mix the prepared dispersed phase base paint with the protective sol, granulate with a multi-color special vacuum screen granulator to obtain color point particles, then add the continuous phase varnish to the color point particles and stir uniformly to obtain the self-cleaning multi-color paint; The preparation method of the modified resin comprises the following steps: 1) Take 4,4'-dicyclohexyl methane diisocyanate 2 g, tetrahydrofuran 10 mL, and isopropyl alcohol 10 mL, place them in a three-necked flask equipped with a magnetic stirrer, stir until completely dissolved to obtain a mixed solution a; take amino propyl terminated polydimethylsiloxane 7 g, tetrahydrofuran 30 mL, and isopropyl alcohol 30 mL, mix them uniformly in a beaker to obtain a mixed solution b; 2) Under nitrogen protection, slowly drop the mixed solution b into the mixed solution a, the dropping time is 1 h, then add 1.8 g of modified nanomaterial, continue to stir for 4 h, and remove the solvent by distillation; The preparation method of the modified nanomaterial comprises the following steps: S1: Take zinc chloride 10 g and sodium hydroxide 12 g, dissolve them in 500 mL of deionized water, stir uniformly, place them in a constant temperature of 80℃ for 10 h under airtight condition, then perform centrifugation, washing, and drying to obtain zinc oxide nanoparticles; S2: Take 0.3 g of cetyltrimethylammonium bromide and 200 mL of deionized water, place them in a flask, stir uniformly, then add 40 g of methyltrimethoxysilane, stir at room temperature until the solution is clear, then add 4 g of zinc oxide nanoparticles, stir uniformly, then quickly add 5 mL of 1 mol / L ammonia water, and stir until a gel is formed; take 10 g of methyltrimethoxysilane and 10 mL of anhydrous ethanol, stir uniformly, then slowly add them to the gel, place them at room temperature for 9 h, then dry and grind to obtain modified zinc oxide nanoparticles; S3: Take 3-aminopropyl triethoxysilane 4 g and anhydrous ethanol 15 mL, mix them thoroughly, add 2 g of modified zinc oxide nanoparticles, ultrasonic for 1 h, heat to 70℃, stir under reflux for 4 h, and remove ethanol under reduced pressure to obtain the product.

2. A method for preparing a self-cleaning multicolor paint, characterized by, It comprises the following steps: a. Preparation of protective sol: add magnesium lithium silicate 3.5 kg and deionized water 25 kg into a disperser and stir until completely dissolved; b Preparation of the dispersed phase base paint: add hydroxyethyl cellulose 1 kg and deionized water 10 kg in the disperser, after stirring to dissolve, add multifunctional additives 200 g, dispersion wetting agent 600 g, defoaming agent 200 g, stirring uniformly, then add kaolin 2.1 kg, titanium dioxide 1.5 kg, mica powder 0.5 kg, glass fiber powder 0.3 kg, stirring uniformly, then add film forming agent 2 kg, antifreeze 1 kg, pigment 1.5 kg, stirring uniformly; c Preparation of the continuous phase varnish: add deionized water 20 kg, modified resin 40 kg, defoaming agent 300 g, film forming agent 2 kg, antifreeze 1 kg in the disperser, stirring uniformly, then slowly add thickening agent 1.5 kg, disperse uniformly; d Preparation of self-cleaning multi-color paint: mix the prepared dispersed phase base paint with protective sol, granulate with multi-color special vacuum screen granulator, get color point particles, then add continuous phase varnish to the color point particles, stirring uniformly, get the self-cleaning multi-color paint; The preparation method of the modified resin comprises the following steps: 1) weigh 1,4-cyclohexane dimethyl diisocyanate 2 g, tetrahydrofuran 10 mL and isopropyl alcohol 10 mL, put them in a three-necked flask equipped with a magnetic stirrer, stir until completely dissolved, obtain a mixed solution a; weigh N-(β-aminoethyl)-γ-aminopropyl trimethoxysilane or N-(β-aminoethyl)-γ-aminopropyl triethoxysilane 7 g, tetrahydrofuran 30 mL and isopropyl alcohol 30 mL, mix them uniformly in a beaker, obtain a mixed solution b; 2) under the protection of nitrogen, slowly drop the mixed solution b into the mixed solution a, the dropping time is 1 h, then add 1.8 g of modified nanometer material, continue to stir for 4 h, remove the solvent by distillation, and then; The preparation method of the modified nanometer material comprises the following steps: S1: weigh zinc chloride 10 g and sodium hydroxide 12 g, dissolve them in 500 mL of deionized water, stir uniformly, place in a constant temperature of 80℃ for 12 h under airtight condition, then centrifuge, wash and dry, obtain zinc oxide nanoparticles; S2: weigh 0.3 g of cetyltrimethylammonium bromide and 200 mL of deionized water, put them in a flask, stir uniformly, then add 40 g of methyltrimethoxysilane, stir until the solution is clear at room temperature, then add 4 g of zinc oxide nanoparticles, stir uniformly, then quickly add 5 mL of 1 mol / L ammonia water, stir until a gel is formed; weigh 10 g of methyltrimethoxysilane and 10 mL of anhydrous ethanol, stir uniformly, then slowly add to the gel, place at room temperature for 12 h, then dry and grind, obtain modified zinc oxide nanoparticles; S3: weigh 3-aminopropyl triethoxysilane 4 g and anhydrous ethanol 15 mL, mix them uniformly, add 2 g of modified zinc oxide nanoparticles, ultrasonic for 1 h, heat to 70℃, stir under reflux for 4 h, remove ethanol under reduced pressure, and then.

3. A method for preparing a self-cleaning multicolor paint, characterized by, Comprise the following steps: a Preparation of protective sol: add magnesium lithium silicate 2 kg and deionized water 20 kg in the disperser, stir until completely dissolved; b Preparation of the dispersed phase base paint: add hydroxyethyl cellulose 0.5 kg and deionized water 8 kg in a disperser, after stirring to dissolve, add multifunctional additive 100 g, dispersion wetting agent 300 g, defoaming agent 100 g, stirring uniformly, then add kaolin 1.4 kg, titanium dioxide 0.5 kg, mica powder 0.3 kg, glass fiber powder 0.1 kg, stirring uniformly, then add film forming additive 1 kg, antifreeze 0.4 kg, pigment 0.5 kg, stirring uniformly; c Preparation of the continuous phase varnish: add deionized water 17 kg, modified resin 30 kg, defoaming agent 100 g, film forming additive 1 kg, antifreeze 0.6 kg in a disperser, stirring uniformly, then slowly add thickening agent 0.7 kg, stirring to uniform; d Preparation of the self-cleaning multi-color paint: mix the prepared dispersed phase base paint with the protective sol, granulate with multi-color special vacuum screen granulator, get color point particles, then add the continuous phase varnish to the color point particles, stirring uniformly, get the self-cleaning multi-color paint. The preparation method of the modified resin comprises the following steps: 1) weigh 2 g of hexamethylene diisocyanate, 10 mL of tetrahydrofuran and 10 mL of isopropyl alcohol, and place them in a three-necked flask equipped with a magnetic stirrer, stirring until completely dissolved to obtain a mixed solution a; weigh 7 g of N-β-(aminoethyl)-γ-aminopropyl methyl dimethoxy silane, 30 mL of tetrahydrofuran and 30 mL of isopropyl alcohol, and mix them uniformly in a beaker to obtain a mixed solution b; 2) under nitrogen protection, slowly drop the mixed solution b into the mixed solution a, the dropping time is 0.5 h, then add 1.5 g of modified nanometer material, continue to stir for 4 h, and remove the solvent by distillation; The preparation method of the modified nanometer material comprises the following steps: S1: weigh 10 g of zinc chloride and 12 g of sodium hydroxide, dissolve them in 500 mL of deionized water, stirring uniformly, place them in a constant temperature of 80℃ for 8 h under airtight condition, then centrifuge, wash and dry to obtain zinc oxide nanoparticles; S2: weigh 0.3 g of cetyl trimethyl ammonium bromide and 200 mL of deionized water, place them in a flask, stirring uniformly, then add 40 g of methyl trimethoxy silane, stirring at room temperature until the solution is clear, then add 4 g of zinc oxide nanoparticles, stirring uniformly, then quickly add 5 mL of 1 mol / L ammonia water, stirring until a gel is formed; weigh 10 g of methyl trimethoxy silane and 10 mL of anhydrous ethanol, stirring uniformly, then slowly add them to the gel, place them at room temperature for 6 h, then dry and grind to obtain modified zinc oxide nanoparticles; S3: weigh 4 g of 3-aminopropyl triethoxysilane and 15 mL of anhydrous ethanol, mix them uniformly, add 2 g of modified zinc oxide nanoparticles, ultrasonic for 0.5 h, heat to 70℃, stirring reflux for 2 h, remove ethanol under reduced pressure, and obtain the product.

4. Process for the preparation of a self-cleaning multicolor paint according to any one of claims 1-3, characterized in that, The multifunctional additive is 2-amino-2-methyl-1-propanol; the film forming additive is alcohol ester twelve.

5. Process for the preparation of a self-cleaning multicolor paint according to any one of claims 1-3, characterized in that, The defoaming agent is one or more of fatty alcohol polyoxyethylene ether, silicone defoaming agent; the dispersing wetting agent is one or more of polyacrylate, silicate, polyvinyl alcohol; the antifreezing agent is one or more of ethylene glycol, propylene glycol; the thickening agent is one or more of polyurethane thickening agent, sodium polyacrylate. The defoaming agent is one or more of fatty alcohol polyoxyethylene ether, silicone defoaming agent; the dispersing wetting agent is one or more of polyacrylate, silicate, polyvinyl alcohol; the antifreezing agent is one or more of ethylene glycol, propylene glycol; the thickening agent is one or more of polyurethane thickening agent, sodium polyacrylate.

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