Preparation method of high-performance easy-to-clean coating suitable for various coil steel coating systems

Abstract

The invention provides a preparation method of a high-performance easy-to-clean coating suitable for various coil steel coating systems. The easy-to-clean coating is prepared from the following raw materials in parts by mass: 20 to 60 parts of water-oil universal solvent A, 0.2 to 10 parts of silane, 20 to 60 parts of deionized water, 1 to 15 parts of silica gel and 1 to 10 parts of water-oil universal solvent B. According to the easy-to-clean material prepared by the preparation method disclosed by the invention, the excellent easy-to-clean effect of the easy-to-clean material can be ensured, the performances such as water resistance, mechanical properties, aging resistance and multi-applicability of an easy-to-clean coating are greatly improved, the application range of the easy-to-clean coating is greatly expanded, various system coatings can have a cleaning effect, and the application range of the easy-to-clean coating is widened. And the method has a wide application scene.

Description

Technical Field

[0001] This invention relates to the field of color-coated steel sheet production technology, specifically to a method for preparing a high-performance, easy-to-clean coating suitable for various coil coating systems. Background Technology

[0002] Color-coated steel sheets are a common decorative building material, boasting a rich variety of colors, excellent weather resistance, and decorative effects. Their unique surface texture and gloss enhance the appearance of buildings, making them more aesthetically pleasing. Furthermore, they can create various artistic effects and special patterns, adding an artistic atmosphere to buildings. However, after exposure to wind, sun, and dust, color-coated steel sheets absorb inorganic dust and organic particles from the air, becoming contaminated. The once vibrant sheets turn grayish, a condition that persists even after rain or manual washing. The advent of easy-to-clean coatings has greatly improved this situation.

[0003] Conventional water-based easy-clean coating systems suffer from poor water resistance, adhesion, and weather resistance. After application, rainwater washes away the easy-clean coating, reducing its service life and limiting the lifespan of color-coated steel sheets to about 3 years. Therefore, it is of great significance to provide an easy-clean coating that has high adhesion to the topcoat of coiled steel and high water and weather resistance. Summary of the Invention

[0004] In view of this, the present invention provides a method for preparing a high-performance easy-clean coating applicable to various coil coating systems. In this method, silane and silica gel, as well as water-oil universal solvent A and water-oil universal solvent B are used to enable the obtained easy-clean coating to be better applied to the topcoat of various coils, forming a dense easy-clean film on the surface of the topcoat. After the topcoat is modified, the entire system has excellent easy-cleaning function.

[0005] The technical solution of the present invention is as follows: A method for preparing a high-performance, easy-to-clean coating suitable for various coil coating systems, wherein the easy-to-clean coating comprises the following components in parts by weight: Water-oil universal solvent A 20-60 parts, silane 0.2-10 parts, deionized water 20-60 parts, silicone gel 1-15 parts, water-oil universal solvent B 1-10 parts.

[0006] Preferably, the above-mentioned method for preparing high-performance, easy-to-clean coatings applicable to various coil coating systems comprises the following steps: Step 1: Add water-oil universal solvent A to the reaction vessel; Step 2: Add silane to the water-oil universal solvent A and stir until homogeneous; Step 3: Continue adding deionized water and stir to mix the system evenly; Step 4: Add silicone gel and stir until well combined; Step 5: Add water-oil universal solvent B, mix well, and you will get the coating product.

[0007] Preferably, in step one, the water-oil universal solvent A is one or more combinations of methanol, ethanol, n-butanol, ethylene glycol, propylene glycol methyl ether, and ethylene glycol butyl ether.

[0008] Preferably, in step two, the silane is one or more combinations of 3-glycidyl etheroxypropylmethyldimethoxysilane, 3-glycidyl etheroxypropyltrimethoxysilane, methacryloyloxypropyltrimethoxysilane, 1,2-bis(trimethoxysilyl)ethane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, SI69, and 1,2-bis(trimethoxysilyl)ethane.

[0009] Preferably, in step four, the silica gel is a nanoscale silica gel; the silica gel brand is one or a combination of the following: Grace's LUDOX AS-30, LUDOX AS-40; Qingdao Haibo's HYTIDE RT95; and Sijing Materials' AC401.

[0010] Preferably, in step five, the universal water-oil solvent B is one or more combinations of methanol, ethanol, n-butanol, ethylene glycol, propylene glycol methyl ether, and ethylene glycol butyl ether; and the universal water-oil solvent B is different from the universal water-oil solvent A. Solvents with different boiling points are beneficial for controlling the evaporation rate and ensuring the integrity of the coating film.

[0011] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. By adding a water-oil universal solvent A, this invention can wet a variety of coil coatings, thereby enabling the easy-to-clean coating to form a complete easy-to-clean coating on the topcoat of various coil coatings when the easy-to-clean coating is applied.

[0012] 2. This invention, by adding silane and silicone gel, and with the synergistic effect of water-oil universal solvent A and water-oil universal solvent B, comprehensively modifies the entire topcoat coating. After high-temperature curing, the organosilane undergoes hydrolysis, condensation, and cross-linking to produce a three-dimensional network reaction film. This film can significantly improve the surface properties of the material, thereby achieving a cleaning effect on the entire surface. Moreover, the products produced during the hydrolysis process contain a large number of "-OH" groups, which can firmly bond with the topcoat, giving the coating excellent adhesion.

[0013] 3. By adjusting the reaction ratio of silane and silicone gel, this invention enables them to react completely, resulting in a film without free functional groups, thereby enhancing the water resistance, chemical resistance, and durability of the easy-to-clean coating.

[0014] 4. This invention utilizes silane in synergy with specific grades of silicone gel to create both hydrophobic and hydrophilic cleaning coatings, thus meeting a variety of customer needs.

[0015] 5. The easy-clean coating provided by this invention improves the surface properties of color-coated steel sheets, enhances adhesion to the topcoat of coiled steel, and gives the easy-clean coating excellent water resistance, adhesion, and weather resistance, ensuring an easy-clean lifespan of over 10 years for the color-coated steel sheets. This product can replace water-based cleaning coatings on the market and is suitable for various coil coatings, enabling easy-clean color-coated steel sheets with a variety of coatings. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 Photos showing carbon black tests on self-cleaning aquamarine coated steel sheets and ordinary aquamarine coated steel sheets.

[0018] Figure 2 Photos of carbon black tests on self-cleaning polyester whitewash board and ordinary polyester whitewash board. Detailed Implementation

[0019] To enable those skilled in the art to better understand the technical solutions of this invention, the technical solutions of this invention will be clearly and completely described below in conjunction with the embodiments of this invention. Obviously, the described embodiments are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this invention.

[0020] The key terms used in this invention are explained below. In the following embodiments, all raw materials are commercially available products.

[0021] Example 1 A method for preparing a high-performance, easy-to-clean coating suitable for various coil coating systems, wherein the easy-to-clean coating comprises the following components in parts by weight: 40 parts of water-oil universal solvent A, 4 parts of organosilane, 4 parts of silicone gel, 2 parts of water-oil universal solvent B, and 50 parts of deionized water; In this embodiment, the water-oil universal solvent A is ethylene glycol butyl ether, which was purchased from Nanjing Gutian Chemical Co., Ltd. The organosilane is 3-glycidyl etheroxypropylmethyldimethoxysilane. In this embodiment, 3-glycidyl etheroxypropylmethyldimethoxysilane was purchased from Nanjing Nengde New Material Technology Co., Ltd., with the brand name SCA-E87T; the silicone gel is Grace's LUDOX AS-40 product. The universal solvent B for water and oil is n-butanol; Using water-oil universal solvent B and water-oil universal solvent A with different boiling points is beneficial for controlling the evaporation rate and ensuring the integrity of the coating film. The above-mentioned method for preparing high-performance, easy-to-clean coatings applicable to various coil coating systems is as follows: Step 1: Add water-oil universal solvent A to the reaction vessel; Step 2: Add silane to the water-oil universal solvent A under low-speed stirring (100 r / min) and stir until homogeneous; Step 3: Continue adding deionized water while stirring, and mix well to ensure the system is homogeneous. Step four, then add the silicone gel under stirring and stir until homogeneous; Step 5: Finally, add water-oil universal solvent B under stirring conditions, mix well, and obtain the coating product. This coating product has the advantages of hydrophobicity and easy cleaning, and can be applied to various coil steel topcoats.

[0022] Example 2 A method for preparing a high-performance, easy-to-clean coating suitable for various coil coating systems, wherein the easy-to-clean coating comprises the following components in parts by weight: 40 parts of water-oil universal solvent A, 4 parts of organosilane, 1 part of silicone gel, 2 parts of water-oil universal solvent B, and 53 parts of deionized water; Among them, the water-oil universal solvent A is ethylene glycol butyl ether, which was purchased from Nanjing Gutian Chemical Co., Ltd. The organosilane was 1,2-bis(trimethoxysilyl)ethane, purchased from Peimu New Materials Technology (Shanghai) Co., Ltd., with the grade name KH-7029; The silicone gel is Qingdao Haibo's HYTIDE RT95 product; The universal solvent B for water and oil is n-butanol; Using water-oil universal solvent B and water-oil universal solvent A with different boiling points is beneficial for controlling the evaporation rate and ensuring the integrity of the coating film. The above-mentioned method for preparing high-performance, easy-to-clean coatings applicable to various coil coating systems is as follows: Step 1: Add water-oil universal solvent A to the reaction vessel; Step 2: Add silane to the water-oil universal solvent A under low-speed stirring (100 r / min) and stir until homogeneous; Step 3: Continue adding deionized water while stirring, and mix well to ensure the system is homogeneous. Step four, then add the silicone gel under stirring and stir until homogeneous; Step 5: Finally, add water-oil universal solvent B under stirring conditions, mix well, and obtain the coating product. In this coating product, the coating obtained by reacting 1,2-bis(trimethoxysilyl)ethane with Qingdao Haibo's HYTIDE RT95 has the advantages of hydrophilicity and easy cleaning, and can be applied to various coil steel topcoats.

[0023] Performance Evaluation: The solid content of the easy-to-clean coating products prepared in Examples 1 and 2 is between 3-8%. Using RDS18# rods, they were coated on conventional aquamarine colored steel sheets, high corrosion-resistant cyan-green colored steel sheets, high corrosion-resistant tin gray colored steel sheets, and polyester white-gray steel sheets, with a film thickness of 0.5-1μm. After coating, they were cured at high temperature of 224-232℃ to obtain colored steel sheets with different properties. In the following experimental measurements of this invention, the high-temperature curing temperature is 230℃.

[0024] In the color-coated steel sheet product of the present invention, the surface of the coiled steel is sequentially coated with a primer, a topcoat, and a self-cleaning coating, and the self-cleaning coating is used to finish the topcoat.

[0025] The carbon black test results for self-cleaning aquamarine coated steel sheets and ordinary aquamarine coated steel sheets are shown below. Figure 1 The carbon black test results for self-cleaning polyester whitewash board and ordinary polyester whitewash board are shown in [the table below]. Figure 2 ; The self-cleaning test results for the above three types of color-coated steel sheets are shown in Table 1 below.

[0026] Table 1. Self-cleaning test results of color-coated steel sheets with different systems

[0027] In Table 1 above, Adhesion: The cross-cut test showed that the cleaning effect still met the national standard after being stuck with tape and soaked in water for 24 hours, indicating that the coating was not removed by tape or water. Hydrophobicity and hydrophilicity: Hydrophilicity and hydrophobicity are determined by testing the contact angle of water droplets on the coating surface using a Krüz droplet surface analyzer; <90° indicates hydrophilicity, and >90° indicates hydrophobicity. Cleanliness: Test the color difference of the carbon black test area. If dE < 1, it meets the standard. For details, refer to GB / T13448. Water resistance: After soaking in deionized water at 25℃ for 24 hours, the carbon black test still meets the standard; Bending performance: After bending the color-coated sheet 180° a total of 4 times, it was peeled off with 3M tape. There was no peeling off. For details, please refer to GB / T 13448. Acid and alkali resistance: Refer to GB / T 13448, immerse the sample in 5% HCl solution at 23±2℃ for 24h, and immerse it in 5% NaOH solution for 24h. Aging performance: The QUV-A aging test of the color-coated sheet showed that the carbon black test still met the standard. For details, please refer to GB / T13448. Test procedure for resistance to carbon black contamination: S1. Stir the prepared 5% carbon black suspension evenly, and use a dropper to add the carbon black suspension to the surface of the horizontally placed sample, allowing the suspension to spread naturally. Sufficient carbon black suspension should be added to ensure that its natural spreading area on the sample surface is not less than 50*50mm. S2, Place the sample with the added carbon black suspension horizontally into the oven, bake at 60°C for 1 hour, and then remove it to cool to room temperature. S3. Rinse with running water while wiping with degreased cotton to remove carbon black slag until no carbon black slag remains on the sample surface. S4. Dry the sample with a powerful hair dryer. S5, measure the color difference between the carbon black contaminated and uncontaminated parts of the sample.

[0028] The results of the above tests are presented in Table 2 below.

[0029] Table 2 Detection Results

[0030] Although the present invention has been described in detail with reference to preferred embodiments, it is not limited thereto. Various equivalent modifications or substitutions can be made to the embodiments of the present invention by those skilled in the art without departing from the spirit and essence of the invention, and such modifications or substitutions should all be within the scope of the present invention. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should also be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be determined by the scope of the claims.

Claims

1. A method for preparing a high-performance, easy-to-clean coating suitable for various coil coating systems, characterized in that, This easy-clean coating comprises the following components in parts by weight: Water-oil universal solvent A 20-60 parts, silane 0.2-10 parts, deionized water 20-60 parts, silicone gel 1-15 parts, water-oil universal solvent B 1-10 parts.

2. The method for preparing a high-performance, easy-to-clean coating applicable to various coil coating systems as described in claim 1, characterized in that, The process is as follows: Step 1: Add water-oil universal solvent A to the reaction vessel; Step 2: Add silane to the water-oil universal solvent A and stir until homogeneous; Step 3: Continue adding deionized water and stir to mix the system evenly; Step 4: Add silicone gel and stir until well combined; Step 5: Add water-oil universal solvent B, mix well, and you will get the coating product.

3. The method for preparing a high-performance, easy-to-clean coating applicable to various coil coating systems as described in claim 2, characterized in that, In step one, the universal solvent A for water and oil is one or a combination of methanol, ethanol, n-butanol, ethylene glycol, propylene glycol methyl ether, and ethylene glycol butyl ether.

4. The method for preparing a high-performance, easy-to-clean coating applicable to various coil coating systems as described in claim 2, characterized in that, In step two, the silane is one or more combinations of 3-glycidyl etheroxypropylmethyldimethoxysilane, 3-glycidyl etheroxypropyltrimethoxysilane, methacryloyloxypropyltrimethoxysilane, 1,2-bis(trimethoxysilyl)ethane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, SI69, and 1,2-bis(trimethoxysilyl)ethane.

5. The method for preparing a high-performance, easy-to-clean coating applicable to various coil coating systems as described in claim 2, characterized in that, In step four, the silica gel is a nanoscale silica gel; the silica gel brand is one or a combination of the following: Grace's LUDOX AS-30 and LUDOX AS-40; Qingdao Haibo's HYTIDE RT95; and Sijing Materials' AC401 gel.

6. The method for preparing a high-performance, easy-to-clean coating applicable to various coil coating systems as described in claim 1, characterized in that, In step five, the universal water-oil solvent B is one or more combinations of methanol, ethanol, n-butanol, ethylene glycol, propylene glycol methyl ether, and ethylene glycol butyl ether; and the universal water-oil solvent B is different from the universal water-oil solvent A.

Images