Metallic coating and preparation method thereof

Abstract

The invention relates to the field of coatings, and particularly discloses a metal texture coating and a preparation method thereof.The metal texture coating is prepared from, by weight, 60-85 parts of polymer emulsion, 20-35 parts of modified aluminum paste, 0.5-1 part of dispersing agent, 0.5-1 part of antioxidant and 10-25 parts of water; the modified aluminum paste is prepared by the following steps: step 1, fully dispersing a coupling agent, a molecular sieve and aluminum paste to obtain a feed liquid; and 2, acidizing polyvinyl alcohol powder, carrying out full contact reaction on the acidized polyvinyl alcohol powder and the vaporous feed liquid, finally adding a surfactant, and uniformly stirring. The preparation method of the metal texture coating comprises the following steps: uniformly mixing and stirring the polymer emulsion, the modified aluminum paste, the dispersing agent, the antioxidant and the water. The coating prepared by the invention is excellent in metal texture, good in glossiness, and excellent in water resistance and adhesive force.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of paint, more particularly, it relates to a metal texture paint and a preparation method thereof. BACKGROUND

[0002] In recent years, with the gradual improvement of people's aesthetic requirements, in order to give the product a high-grade and modern sense, the paint with metal texture is more and more popular and valued. The metal texture paint is a special paint, which forms a similar metal gloss and texture effect on the surface. In order to make the traditional paint have metal texture, aluminum silver paste is usually added to the traditional paint. The aluminum silver paste is a paste-like metal pigment, which has snowflake, fish scale and silver dollar shape. The formation of the paint with metal texture requires the uniform arrangement of the flaky aluminum in the aluminum silver paste on the surface of the coating layer formed by the paint. However, the aluminum silver paste is easy to agglomerate and arrange unevenly in the paint, which reduces the metal texture and gloss, and affects the adhesion and water resistance between the paint and the base layer. SUMMARY

[0003] In order to effectively improve the water resistance of the paint and improve the metal texture and gloss of the paint, the present application provides a metal texture paint and a preparation method thereof.

[0004] In the first aspect, the present application provides a metal texture paint and a preparation method thereof, which adopts the following technical scheme:

[0005] A metal texture paint, comprising the following raw materials by weight: 60-85 parts of polymer emulsion, 20-35 parts of modified aluminum silver paste, 0.5-1 part of dispersant, 0.5-1 part of antioxidant, and 10-25 parts of water.

[0006] The modified aluminum silver paste is prepared by the following steps:

[0007] Step 1, the coupling agent, molecular sieve and aluminum silver paste are fully dispersed to obtain a liquid;

[0008] Step 2, after the polyvinyl alcohol powder is acidified, it is fully contacted and reacted with the misty liquid, and finally the surfactant is added and stirred uniformly.

[0009] The application modifies the aluminum silver paste, uses molecular sieve as the carrier, and cooperates with the coupling agent to make the aluminum silver paste uniformly dispersed and arranged in the system, improve the metal texture and gloss of the coating, wherein the cross-linking structure formed by the polyvinyl alcohol and the coupling agent makes the polyvinyl alcohol powder dissolved in water and the polymer emulsion have excellent adhesive strength and water resistance after forming a film, and the adhesion of the paint film to the substrate is improved; the acidified polyvinyl alcohol can be better cross-linked, the introduction of the surfactant can further adjust the compatibility of the system and the bubble size and density of the system, form closed small bubbles, and the coupling agent can also eliminate some original large bubbles, reduce the water absorption due to the open pore structure in the construction process, and thus improve the water resistance of the paint film.

[0010] Further, the component usage of the modified aluminum silver paste is as follows: the coupling agent is 1-3 parts, the molecular sieve is 2-5 parts, the aluminum silver paste is 12-25 parts, the polyvinyl alcohol powder is 6-13 parts, and the surfactant is 0.1-0.2 parts.

[0011] By using the above scheme, the component usage of the modified aluminum silver paste is optimized, the quality of the modified aluminum silver paste is further improved, and the comprehensive performance of the coating is improved.

[0012] Further, the surfactant is triterpene saponin or lignin sulfonate.

[0013] Further, in step 2, the raw material for acidification treatment is citric acid or oxalic acid.

[0014] Further, the coupling agent is an amino silane coupling agent and / or a vinyl silane coupling agent.

[0015] As a further preferred scheme of the coupling agent, the coupling agent is an amino silane coupling agent.

[0016] Further, the polymer emulsion includes one or more of acrylic emulsion, styrene-acrylic emulsion, and polyurethane emulsion.

[0017] Further, the dispersant is VOK-41000 dispersant or BYK-108 dispersant.

[0018] In a second aspect, the application provides a preparation method of a metal texture coating, which uses the following technical scheme:

[0019] A preparation method of a metal texture coating includes the following steps: mixing and stirring the polymer emulsion, the modified aluminum silver paste, the dispersant, the antioxidant, and water uniformly.

[0020] In summary, this application has the following beneficial effects: By modifying the aluminum silver paste, using molecular sieves as a carrier, and combining it with a coupling agent, the aluminum silver paste is uniformly dispersed and arranged in the system, improving the metallic texture and gloss of the coating. The polyvinyl alcohol forms a cross-linked structure with the coupling agent, resulting in excellent adhesive strength and water resistance when the polyvinyl alcohol powder is dissolved in water and combined with the polymer emulsion to form a film, thus improving the adhesion between the paint film and the substrate. The acidified polyvinyl alcohol can better cross-link, and the introduction of surfactants can further adjust the compatibility of the system and the size and density of bubbles, forming closed-cell microbubbles. The coupling agent can also eliminate some of the original large bubbles, reducing the water absorption caused by the open-cell structure during construction, thereby improving the water resistance of the paint film. Detailed Implementation

[0021] The embodiments of the present invention will be described in detail below with reference to the examples. However, those skilled in the art will understand that the following examples are only for illustrating the present invention and should not be regarded as limiting the scope of the present invention. Specific conditions not specified in the examples shall be carried out according to conventional conditions or conditions recommended by the manufacturer. Reagents or instruments whose manufacturers are not specified are all conventional products that can be purchased commercially.

[0022] Example of preparation of modified aluminum silver paste

[0023] Preparation Example 1

[0024] Modified aluminum silver paste is prepared through the following steps:

[0025] Step 1: Disperse 1 kg of vinyl silane coupling agent, 2 kg of molecular sieve and 12 kg of aluminum silver paste for 10 min to obtain a liquid. The molecular sieve has a particle size of 0.04-0.08 mm and is of type 3A.

[0026] Step 2: After acidifying 6 kg of polyvinyl alcohol powder in an 8% oxalic acid solution for 20 min, it is fully reacted with the mist-like liquid. Finally, 0.1 kg of the surfactant triterpenoid saponin is added and stirred evenly. The polyvinyl alcohol grade is 1788.

[0027] Preparation Example 2

[0028] Modified aluminum silver paste is prepared through the following steps:

[0029] Step 1: Disperse 2 kg of vinyl silane coupling agent, 1 kg of amino silane coupling agent, 5 kg of molecular sieve and 25 kg of aluminum silver paste for 20 min to obtain a liquid. The molecular sieve has a particle size of 0.03-0.07 mm and is of type 5A.

[0030] Step 2: After acidifying 13 kg of polyvinyl alcohol powder in a 10% citric acid solution for 20 min, it is fully reacted with the mist-like liquid. Finally, 0.2 kg of sodium lignosulfonate surfactant is added and stirred evenly. The polyvinyl alcohol grade is 2488.

[0031] Preparation Example 3

[0032] Modified aluminum silver paste is prepared through the following steps:

[0033] Step 1: Disperse 2.2 kg of aminosilane coupling agent, 3.5 kg of molecular sieve and 9 kg of aluminum silver paste for 15 min to obtain a liquid. The molecular sieve has a particle size of 0.01-0.05 mm and is of type 3A.

[0034] Step 2: After acidifying 9 kg of polyvinyl alcohol powder in a 10% oxalic acid solution for 20 min, it is fully reacted with the mist-like liquid. Finally, 0.15 kg of the surfactant triterpenoid saponin is added and stirred evenly. The polyvinyl alcohol grade is 1788.

[0035] Preparation Example 4

[0036] Modified aluminum silver paste is prepared through the following steps:

[0037] Step 1: Disperse 1 kg of epoxy silane coupling agent, 2 kg of molecular sieve and 15 kg of aluminum silver paste for 10 min to obtain a liquid. The molecular sieve has a particle size of 0.04-0.08 mm and is of type 3A.

[0038] Step 2: After acidifying 6 kg of polyvinyl alcohol powder in an 8% acetic acid solution for 20 min, it is fully reacted with the mist-like liquid. Finally, 0.1 kg of surfactant alkyl glycoside is added and stirred evenly. The polyvinyl alcohol grade is 1788.

[0039] Comparative Preparation Example 1

[0040] The modified aluminum silver paste is prepared by the following steps: 1 kg of vinyl silane coupling agent and 12 kg of aluminum silver paste are fully dispersed and stirred evenly.

[0041] Comparative Preparation Example 2

[0042] Modified aluminum silver paste is prepared by the following steps: 12 kg of aluminum silver paste, 6 kg of polyvinyl alcohol powder, and 0.1 kg of surfactant triterpenoid saponins are stirred evenly, wherein the polyvinyl alcohol grade is 1788.

[0043] Example

[0044] Example 1

[0045] A method for preparing a metallic textured coating includes the following steps: mixing and stirring 60 kg of styrene-acrylic emulsion, 20 kg of modified aluminum silver paste prepared in Preparation Example 1, 1 kg of dispersant, 0.5 kg of antioxidant, and 10 kg of water until homogeneous; wherein the styrene-acrylic emulsion has CAS number 25085-34-1, the dispersant is Walker VOK-41000 dispersant, and the antioxidant is antioxidant 1500.

[0046] Example 2

[0047] A method for preparing a metallic coating includes the following steps: mixing and stirring 85 kg of polyurethane emulsion, 35 kg of modified aluminum silver paste prepared in Preparation Example 1, 0.5 kg of dispersant, 1 kg of antioxidant, and 25 kg of water until homogeneous; wherein the CAS number of the polyurethane emulsion is 51852-81-4, the dispersant is BYK-108 dispersant, and the antioxidant is antioxidant 1010.

[0048] Example 3

[0049] A method for preparing a metallic textured coating includes the following steps: mixing and stirring 70 kg of acrylic emulsion, 30 kg of modified aluminum silver paste prepared in Preparation Example 1, 0.8 kg of dispersant, 0.75 kg of antioxidant, and 20 kg of water until homogeneous; wherein the acrylic emulsion has CAS number 9003-01-4, the dispersant is Walker VOK-41000 dispersant, and the antioxidant is antioxidant 1500.

[0050] Example 4

[0051] The difference from Example 3 is that the modified aluminum silver paste prepared in Preparation Example 2 was used, while the rest were the same as in Example 3.

[0052] Example 5

[0053] The difference from Example 3 is that the modified aluminum silver paste prepared in Preparation Example 3 was used, while the rest are the same as in Example 3.

[0054] Example 6

[0055] The difference from Example 3 is that the modified aluminum silver paste prepared in Preparation Example 4 was used, while the rest were the same as in Example 3.

[0056] Comparative Example

[0057] Comparative Example 1

[0058] The difference from Example 5 is that the modified aluminum silver paste prepared in Comparative Preparation Example 1 was used, while the rest were the same as in Example 5.

[0059] Comparative Example 2

[0060] The difference from Example 5 is that the modified aluminum silver paste prepared in Comparative Preparation Example 2 was used, while the rest were the same as in Example 5.

[0061] Comparative Example 3

[0062] The difference from Example 5 is that commercially available aluminum silver paste was used to replace the modified aluminum silver paste prepared in Preparation Example 3. The aluminum silver paste was purchased from Hefei Xuyang Aluminum Pigment Co., Ltd., and the other components were the same as in Example 5.

[0063] Performance testing

[0064] The metallic coating samples prepared in Examples 1-6 and Comparative Examples 1-3 were tested for water resistance according to GB / T1733--93 "Test Method for Water Resistance of Coating Film". After grinding, cleaning and drying the surface of a tinplate with dimensions of 120mm×50mm×0.3mm, the coating was evenly sprayed onto the substrate and dried at room temperature for 1 hour, and then dried at 60℃ for 3 hours to obtain a coating with a thickness of 50nm. Distilled water was added to a glass water tank and the water temperature was adjusted to 90±2℃. Five test panels were placed in each group, and two-thirds of the test panels were immersed in water. The test panels were checked every 24 hours and every 12 hours after 240 hours. The time when two or more test panels in each group showed signs of loss of gloss, discoloration, blistering, wrinkling, peeling or rusting was recorded.

[0065] The metallic coating samples prepared in Examples 1-6 and Comparative Examples 1-3 were subjected to adhesion tests according to the national standard GB / T 9286-1998. After grinding, cleaning and drying the surface of a tinplate with dimensions of 120mm×50mm×0.3mm, the coating was sprayed onto the substrate and dried at room temperature for 1 hour, and then dried at 60℃ for 3 hours to obtain a coating with a thickness of 50nm. A cross-cutting device with a grid spacing of was used to make a grid, and then transparent tape was used to stick the grid area tightly and then pull off the tape. Five test plates were used in each group, and the peeling of the coating in the grid area was observed to determine its adhesion level. The test results are shown in Table 1.

[0066] The metallic coating samples prepared in Examples 1-6 and Comparative Examples 1-3 were tested for gloss according to the national standard GB / T 9754-2007. After grinding, cleaning and drying the surface of a tinplate with dimensions of 120mm×50mm×0.3mm, the coating was sprayed onto the substrate and dried at room temperature for 1 hour, and then dried at 60℃ for 3 hours to obtain a coating with a thickness of 50nm. Five test plates were used in each group. The gloss of the coating at different positions was measured with a gloss meter at 60°, and the average value was obtained as the actual gloss of the coating. The test results are shown in Table 1.

[0067] The metallic texture samples prepared in Examples 1-6 and Comparative Examples 1-3 were subjected to metallic texture testing: After grinding, cleaning and drying the surface of a tinplate with dimensions of 120mm×50mm×0.3mm, the coating was sprayed onto the substrate and dried at room temperature for 1 hour, and then dried at 60℃ for 3 hours to obtain a coating with a thickness of 50nm. Five test plates were used in each group, and the metallic texture level was obtained by visual inspection. There were five levels in total, from high to low: high, relatively high, medium, relatively low and low. The test results are shown in Table 1.

[0068] Table 1

[0069] Water resistance / h Adhesion Gloss (60°) Metallic feel grade Example 1 312 1st grade 91.3 High Example 2 312 1st grade 90.9 High Example 3 324 0th grade 92.8 High Example 4 324 0th grade 93.1 High Example 5 336 0th grade 94.2 High Example 6 324 1st grade 91.5 High Comparative Example 1 240 3rd grade 80.3 Medium Comparative Example 2 252 2nd grade 81.7 Medium Comparative Example 3 240 3rd grade 78.6 Low

[0070] As can be seen from Examples 1-6 and Table 1, the coatings obtained using the raw material components of this application have excellent metallic texture and gloss, as well as good adhesion to the substrate and excellent water resistance. As can be seen from Examples 5 and Comparative Examples 1-3 and Table 1, the preparation method and raw material components of the modified aluminum silver paste have a significant impact on the overall performance of the product.

[0071] 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 metallic paint characterized by, The raw materials include the following components by weight: polymer emulsion 60-85 parts, modified aluminum silver paste 20-35 parts, dispersant 0.5-1 part, antioxidant 0.5-1 part, and water 10-25 parts; The modified aluminum silver paste is prepared by the following steps: Step 1: disperse the coupling agent, molecular sieve and aluminum silver paste to obtain a slurry; Step 2: after acid treatment of the polyvinyl alcohol powder, fully contact the slurry with the mist, and finally add a surfactant and stir uniformly.

2. The metallic paint according to claim 1, characterized in that: The components used in the modified aluminum silver paste are as follows by weight: coupling agent 1-3 parts, molecular sieve 2-5 parts, aluminum silver paste 12-25 parts, polyvinyl alcohol powder 6-13 parts, and surfactant 0.1-0.2 parts.

3. The metallic paint according to claim 2, characterized in that: The surfactant is triterpene saponin or lignin sulfonate.

4. The metallic paint of claim 1, wherein: In step 2, the acid treatment uses citric acid or oxalic acid.

5. The metallic paint of claim 2, wherein: The coupling agent is amino silane coupling agent and / or vinyl silane coupling agent.

6. The metallic paint of claim 1, wherein: The polymer emulsion includes one or more of acrylic emulsion, styrene-acrylic emulsion, and polyurethane emulsion.

7. The metallic paint of claim 1, wherein: The dispersant is VOK-41000 dispersant or BYK-108 dispersant.

8. The method of preparing a metallic paint according to claim 1, characterized in that: The method includes the following steps: mix and stir the polymer emulsion, modified aluminum silver paste, dispersant, antioxidant, and water uniformly.