High-weather-resistant coating applied to automobile real wood interior parts, and preparation method and application thereof

Abstract

The application relates to a high-weather-resistant paint applied to automobile real wood interior parts and a preparation method and application thereof, and belongs to the technical field of automobile paints. The high-weather-resistant paint provided by the application comprises the following components in parts by weight: 45-65 parts of organic silicon modified resin, 5-15 parts of acrylic resin, 2-5 parts of an antiseptic bactericide, 1-3 parts of a light stabilizer and 10-35 parts of an organic solvent; the paint provided by the application is water-white and transparent, has good surface performance and good low-temperature impact resistance, has excellent permeability and sealing performance, can effectively inhibit the yellowing and aging defects of real wood itself or dyed wood skin and the like in a long period in a harsh environment such as high temperature, high humidity and sunlight exposure, and has high application value in automobile real wood interior parts. The high-weather-resistant paint provided by the application can react with water in real wood to permanently and firmly seal the water in wood fibers after being applied to automobile real wood interior parts for surface treatment, realizes the purpose of being combined with wood, and fundamentally solves the long-acting problem of the prior art.

Description

Technical Field

[0001] This invention relates to the technical field of coatings, specifically to a high weather-resistant coating for automotive wood interior trim, its preparation method, and its application. Background Technology

[0002] Real wood, as a natural material, is widely used in automotive interiors due to its unique grain, texture, and three-dimensionality. It is often inlaid in areas such as dashboards, center consoles, door panels, and steering wheels to enhance the quality of the car's interior, and is particularly prevalent in luxury car brands. Meanwhile, engineered wood veneers, made using biomimetic principles and processed through bleaching and dyeing, are also favored in the real wood automotive interior market because they overcome the shortcomings of natural wood and offer advantages such as strong three-dimensional texture, excellent color uniformity, and high consistency of the substrate. However, regardless of whether the interior parts are made of real wood or engineered wood veneers, they are susceptible to fading, yellowing, and aging due to environmental temperature differences and sun exposure during use, which affects the quality of the interior. Therefore, surface protection with coatings is typically used.

[0003] The domestic market for automotive wood interior coatings mainly uses imported weather-resistant coatings, such as those from BASF in Germany and Fuji in the UK. However, existing weather-resistant coatings generally involve adding UV absorbers to the coating and applying it to the surface of the product. Their function is to absorb UV light and protect the coating from ultraviolet radiation, primarily preventing yellowing and aging of the surface coating. Over time, the concentration of UV absorbers in the coating will decrease, causing the coating to age and degrade prematurely. UV light can then penetrate the coating and directly reach the wood itself, failing to effectively inhibit fading, yellowing, and aging defects in the wood itself or dyed veneers in the long term. This falls far short of the high weather resistance requirements for automotive wood interior coatings and cannot pass the stringent long-term testing of automotive wood interior coatings. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of existing technologies and provide a high weather-resistant coating for automotive wood interior trim, its preparation method, and its application. The high weather-resistant coating provided by this invention has good surface properties, strong penetration and sealing properties, excellent weather resistance such as high temperature resistance and light aging resistance, good scratch resistance, and strong practicality, making it highly valuable for use in automotive wood interior trim coatings.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0006] In a first aspect, the present invention provides a coating comprising the following raw materials in parts by weight: 45-65 parts of silicone-modified resin, 5-15 parts of acrylic resin, 1-3 parts of light stabilizer, 0.3-1 parts of antioxidant, and 10-35 parts of organic solvent; wherein the silicone-modified resin is a polysiloxane-modified acrylic resin with vinyl groups, and the acrylic resin is an oil-based acrylic resin.

[0007] Organosilicon-modified resins possess strong bonding energy in their main molecular structure, consisting of siloxane bonds (SI-O-Si), preventing aging and discoloration even in high-temperature environments. Combined with a mixture of light stabilizers and antioxidants, the weather resistance of coatings can be comprehensively improved. By incorporating the aforementioned specific components and proportions, organosilicon-modified acrylic resins exhibit excellent adhesion to commonly used automotive wood interior substrates, forming a coating with moderate hardness and good resistance to low-temperature impact, scratches, and weathering.

[0008] Adding the above-mentioned amount of acrylic resin to the silicone-modified resin and curing it together with the silicone-modified resin to form a coating can significantly improve the surface properties of the coating and enhance its adhesion to common substrates such as PC / ABS+real wood. If insufficient acrylic resin is added, the adhesion will decrease and the low-temperature impact resistance will be poor; if too much acrylic resin is added, it will not have long-term weather resistance and the scratch resistance will be reduced.

[0009] The light stabilizer is a mixture of benzotriazole UV absorber and hindered amine light stabilizer. This mixture is added to an organosilicon-modified resin in the specified weight proportions, and the coating is formed through room temperature curing. The synergistic effect of these components results in high stability and good resistance to photoaging. Insufficient light stabilizer leads to poor photoaging resistance of the coating; excessive light stabilizer results in poor scratch resistance.

[0010] The antioxidant is a mixture of hindered phenolic antioxidants and phosphite antioxidants. This antioxidant mixture is added to an organosilicon-modified resin in the specified weight proportions, and a coating is formed through room temperature curing. The synergistic effect of these antioxidants results in high stability and good heat aging resistance. Insufficient antioxidant addition leads to slightly poorer heat aging resistance in the coating; excessive antioxidant addition has no other positive effects.

[0011] The high weather-resistant coating provided by this invention has excellent resistance to light aging, high temperature, and low temperature impact. It can maintain stable adhesion, without cracking or discoloration even after long-term exposure to light, humidity, and high and low temperature environments. Furthermore, the coating formed maintains good performance in chemical resistance, abrasion resistance, and scratch resistance, and has high application value in the field of coating for automotive wood interiors and other similar products.

[0012] More preferably, the modified acrylic resin is a polysiloxane-modified organosilicon resin; further, the organic solvent is a mixture of propylene glycol methyl ether acetate, propylene glycol methyl ether, and ethyl acetate, wherein the mass ratio of propylene glycol methyl ether acetate, propylene glycol methyl ether, and ethyl acetate is 1:3:1. Using organosilicon-modified resin as the main component, its main molecular structure, siloxane bonds (SI-O-Si), has strong bonding energy and will not age or discolor in high-temperature irradiation. Combined with the aforementioned volatile organic solvent, each component can be fully dissolved, the overall viscosity can be moderately controlled, and both volatility and permeability can be considered, thereby improving the color stability of the real wood under ultraviolet light irradiation.

[0013] Preferably, the light stabilizer includes benzotriazole, and the ultraviolet absorber is at least one of 3-[3-(2-H-benzotriazole-2-yl)-4-hydroxy-5-tert-butylphenyl]-propionic acid-polyethylene glycol 300, 2-(2'-hydroxy-3'-5-di-tert-phenyl)-5-chlorobenzotriazole, or 2-(2'-hydroxy-5'-methylphenyl)benzotriazole. The light stabilizer, employing a mixture of ultraviolet absorber and hindered amine light stabilizer, synergistically absorbs ultraviolet light in the 290nm-400nm range, captures free radicals, and quenches excited-state molecules, thereby delaying coating aging.

[0014] More preferably, the mass ratio of the benzotriazole UV absorber to the hindered amine light stabilizer used in the light stabilizer is 2:1. Using the aforementioned specific type of benzotriazole UV absorber and hindered amine light stabilizer in a 2:1 mass ratio can improve the photoaging performance of the coating on automotive wood interior substrates. Excessive use of the hindered amine light stabilizer reduces scratch resistance; conversely, insufficient use degrades the coating's photoaging resistance.

[0015] Preferably, the raw materials for preparing the coating further include at least one of a preservative, bactericide, defoamer, antioxidant, and wetting agent. Using the above-mentioned additives in parts by weight can effectively reduce the surface tension of the coating, allowing it to penetrate deeply into the real wood substrate, promoting a tight bond between the coating and the real wood substrate, and forming a uniform and smooth surface.

[0016] More preferably, the mass ratio of hindered phenolic antioxidant to phosphite antioxidant is 1:1. Using the aforementioned specific types of hindered phenolic antioxidants and phosphite antioxidants in a 1:1 mass ratio can improve the thermal aging performance of the coating on automotive wood interior substrates. If the proportion of hindered phenolic antioxidant is too low, the coating's thermal aging resistance will deteriorate. Conversely, a high proportion will have no positive effect and will increase product costs.

[0017] Preferably, the antioxidant includes at least one of hindered phenolic antioxidants and phosphite antioxidants; the use of antioxidants can capture generated free radicals or decompose generated macromolecular hydroperoxides, so as to prevent the aging chain reaction from being triggered, and play a protective role against thermo-oxidative aging.

[0018] Preferably, the preservative and bactericide is dimethyloldimethylhydantoin (DMDMH). Using a preservative and bactericide can effectively prevent mold growth, blackening, and discoloration of the real wood substrate, and also improves the weather resistance of the coating.

[0019] More preferably, the coating comprises the following raw materials in parts by weight:

[0020] The following ingredients are combined in the specified proportions: 50-65 parts silicone-modified resin, 5-10 parts acrylic resin, 2-3 parts preservative and bactericide, 0.5-2 parts wetting agent, 0.1-0.5 parts defoamer, 1-3 parts light stabilizer, 0.3-1 part antioxidant, and 10-35 parts organic solvent. This combination helps to further improve the weather resistance, especially the resistance to light aging, of the coating. Increasing the amount of silicone-modified resin reduces the coating's resistance to low-temperature impact and decreases adhesion.

[0021] Secondly, the present invention provides a method for preparing the high weather-resistant coating, comprising the following steps:

[0022] (1) Mix acrylic resin, light stabilizer, antioxidant, preservative and bactericide, wetting agent and part of solvent to obtain a premix;

[0023] (2) Mix the organosilicon modified resin, the premix described in step (1) and the remaining solvent, then add the defoamer and stir. After adjusting the viscosity, filter through a 400-mesh filter to obtain the high weather-resistant coating.

[0024] Preferably, in step (1), the mixing speed is 1000-1200 rpm / min, and the mixing time is 15-30 min, preferably 20 min.

[0025] Preferably, in step (2), the mixing speed is 800-1000 rpm / min, the mixing time is 30-40 min, preferably 35 min; the viscosity of the high weather-resistant coating is 10±1s (25℃, Coat 4 cup).

[0026] Thirdly, the present invention provides the application of the high weather-resistant coating in the preparation of automotive wood interior coatings.

[0027] The aforementioned coating can be sprayed onto various substrates such as PC / ABS and real wood to form a transparent coating. The coating exhibits excellent adhesion, good low-temperature impact resistance, scratch resistance, and weather resistance. It can pass long-term high-temperature and xenon lamp aging tests without cracking or discoloration. It can be applied to luxury car interiors, inlaid in areas such as the dashboard, center console, door panels, and steering wheel to enhance the quality of automotive trim, improve aesthetics, and enhance the user experience.

[0028] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0029] The high weather-resistant coating provided by this invention effectively protects automotive wood interior substrates from UV aging, thermo-oxidative aging, and mildew discoloration by using a combination of organosilicon-modified resin, light stabilizer, antioxidant, and preservative / bacterial agent. The high weather-resistant coating is applied to the surface of the wood automotive trim through spraying or impregnation, allowing it to quickly penetrate the wood substrate. Because the modified organosilicon resin macromolecular chain contains vinyl groups, the light stabilizer mixture is both highly compatible with and can chemically react with these groups, thus fixing them to the macromolecular chain through chemical linkage. It also retains a certain degree of hydrolyzable alkoxy groups, causing hydrolytic condensation between silanol molecules. Then, through methods such as rinsing and heating, it reacts with the moisture in the wood, permanently and firmly sealing it within the wood fibers, achieving the purpose of chemical bonding with the wood. This fundamentally solves the problem of long-term weather resistance achieved by adding UV absorbers to the surface coating of existing products. Detailed Implementation

[0030] To better illustrate the purpose, technical solution, and advantages of the present invention, the present invention will be further described below in conjunction with specific embodiments.

[0031] To better illustrate the purpose, technical solution, and advantages of the present invention, the present invention will be further described below in conjunction with specific embodiments. Unless otherwise specified, the experimental methods used in the following embodiments are conventional methods; the materials and reagents used, unless otherwise specified, are commercially available reagents and materials.

[0032] In the following examples and comparative examples, some component information of the coatings is as follows:

[0033] Organosilicon modified resin: manufactured by Hubei Sihai New Materials Co., Ltd., brand name SH9604A, viscosity in 40wt% solution at 25℃ is 15-40s (Ford cup 4).

[0034] Acrylic resin: Oil-based acrylic resin, purchased from Guangzhou Jingyi New Materials Co., Ltd., brand: Mitsubishi BR-113 from Japan, with a viscosity of 250-340 mPa·s in a 40wt% toluene solution at 25℃ and an average molecular weight of 30,000.

[0035] Preservatives and bactericides: purchased from Guangzhou Zhonghong Biotechnology Co., Ltd.;

[0036] UV absorbers: purchased from Shanghai Kaiyin Chemical Co., Ltd., brand names Tinuvin 1130 and Tinuvin 400;

[0037] Hindered amine light stabilizers: purchased from Shanghai Kaiyin Chemical Co., Ltd., brand names Tinuvin 765, Tinuvin 292 and Tinuvin 123;

[0038] Hindered phenolic antioxidants: purchased from Shanghai Kaiyin Chemical Co., Ltd., brand names irganox1010 and irganox1076;

[0039] Phosphite antioxidants: purchased from Shanghai Kaiyin Chemical Co., Ltd., brand names Irgafos168 and Zhiyi 3010;

[0040] Wetting agent: Manufacturer is Evonik Specialty Chemicals (Shanghai) Co., Ltd., brand name is TegoWet270, Twin4100.

[0041] Defoamer: Manufacturer is BYK Chemical Co., Ltd., brand name is byk-055, byk-052.

[0042] Unless otherwise specified, all other materials and reagents used in the examples are commercially available.

[0043] Example 1

[0044] One embodiment of the coating of the present invention comprises the following raw materials in parts by weight:

[0045] The composition includes 56 parts of silicone-modified resin (Sihai New Materials SH9604A), 6 parts of acrylic resin (Mitsubishi BR-113), 2.2 parts of preservative and bactericide (Guangzhou Zhonghong DMDMH), 1.3 parts of wetting agent (Evonik Twin4100), 0.2 parts of defoamer, 3 parts of light stabilizer, 0.3 parts of antioxidant, and 33 parts of solvent.

[0046] in,

[0047] The light stabilizer is a mixture of ultraviolet absorber and hindered amine light stabilizer in a mass ratio of 2:1; the ultraviolet absorber is Tinuvin 400 and the hindered amine light stabilizer is Tinuvin 123.

[0048] The antioxidant is a mixture of hindered phenolic antioxidant and phosphite antioxidant in a 1:1 mass ratio. The hindered phenolic antioxidant is Irganox 1010; the phosphite antioxidant is Irgafos 168.

[0049] The organic solvent is a mixture of propylene glycol methyl ether acetate, propylene glycol methyl ether, and ethyl acetate in a mass ratio of 1:3:1.

[0050] The wetting agent is Twin410.

[0051] The defoamer is BYK-052.

[0052] The preparation method of high weather-resistant coating includes the following steps:

[0053] (1) Mix acrylic resin, light stabilizer, antioxidant, preservative and bactericide, wetting agent and part of solvent. The mixing speed is 1000-1200 rpm / min and the mixing time is 20 min to obtain a premix.

[0054] (2) Mix the organosilicon modified resin, the premix described in step (1) and the remaining solvent. The mixing speed is 800-1000 rpm / min and the mixing time is 35 min. Then add the defoamer and stir. Adjust the viscosity to 10±1s (25℃, Forecast cup 4). Mix evenly to obtain the final product.

[0055] Example 2

[0056] A high weather-resistant coating comprises the following components in parts by weight: 50 parts of silicone-modified resin (Sihai New Materials SH9604A), 5 parts of acrylic resin (Mitsubishi BR-113), 2 parts of preservative and bactericide (Guangzhou Zhonghong DMDMH), 1.5 parts of wetting agent (Evonik Twin4100), 0.1 parts of defoamer, 3 parts of light stabilizer, 0.3 parts of antioxidant, and 30 parts of solvent;

[0057] in,

[0058] The light stabilizer is a mixture of ultraviolet absorber and hindered amine light stabilizer in a mass ratio of 2:1; the ultraviolet absorber is Tinuvin 400 and the hindered amine light stabilizer is Tinuvin 123.

[0059] The antioxidant is a mixture of hindered phenolic antioxidant and phosphite antioxidant in a 1:1 mass ratio. The hindered phenolic antioxidant is Irganox 1010; the phosphite antioxidant is Irgafos 168.

[0060] The organic solvent is a mixture of propylene glycol methyl ether acetate, propylene glycol methyl ether, and ethyl acetate in a mass ratio of 1:3:1.

[0061] The wetting agent is Twin4100.

[0062] The defoamer is BYK-052.

[0063] The preparation method of high weather-resistant coating includes the following steps:

[0064] (1) Mix acrylic resin, light stabilizer, antioxidant, preservative and bactericide, wetting agent and part of solvent. The mixing speed is 1000-1200 rpm / min and the mixing time is 20 min to obtain a premix.

[0065] (2) Mix the organosilicon modified resin, the premix described in step (1) and the remaining solvent. The mixing speed is 800-1000 rpm / min and the mixing time is 35 min. Then add the defoamer and stir. Adjust the viscosity to 10±1s (25℃, Forecast cup 4). Mix evenly to obtain the final product.

[0066] Example 3

[0067] A high weather-resistant coating comprises the following components in parts by weight: 65 parts of silicone-modified resin (Sihai New Materials SH9604A), 6 parts of acrylic resin (Mitsubishi BR-113), 2 parts of preservative and bactericide (Guangzhou Zhonghong DMDMH), 2 parts of wetting agent (Evonik Twin4100), 0.5 parts of defoamer, 3 parts of light stabilizer, 1 part of antioxidant, and 24 parts of solvent;

[0068] in,

[0069] The light stabilizer is a mixture of ultraviolet absorber and hindered amine light stabilizer in a mass ratio of 2:1; the ultraviolet absorber is Tinuvin 400 and the hindered amine light stabilizer is Tinuvin 123.

[0070] The antioxidant is a mixture of hindered phenolic antioxidant and phosphite antioxidant in a 1:1 mass ratio. The hindered phenolic antioxidant is Irganox 1010; the phosphite antioxidant is Irgafos 168.

[0071] The organic solvent is a mixture of propylene glycol methyl ether acetate, propylene glycol methyl ether, and ethyl acetate in a mass ratio of 1:3:1.

[0072] The wetting agent is Twin4100.

[0073] The defoamer is BYK-052.

[0074] The preparation method of high weather-resistant coating includes the following steps:

[0075] (1) Mix acrylic resin, light stabilizer, antioxidant, preservative and bactericide, wetting agent and part of solvent. The mixing speed is 1000-1200 rpm / min and the mixing time is 20 min to obtain a premix.

[0076] (2) Mix the organosilicon modified resin, the premix described in step (1) and the remaining solvent. The mixing speed is 800-1000 rpm / min and the mixing time is 35 min. Then add the defoamer and stir. Adjust the viscosity to 10±1s (25℃, Forecast cup 4). Mix evenly to obtain the final product.

[0077] Example 4

[0078] One embodiment of the coating of the present invention comprises the following raw materials in parts by weight:

[0079] The composition includes 48 parts of silicone-modified resin (Sihai New Materials SH9604A), 6 parts of acrylic resin (Mitsubishi BR-113), 2.2 parts of preservative and bactericide (Guangzhou Zhonghong DMDMH), 1.3 parts of wetting agent (Evonik Twin4100), 0.2 parts of defoamer, 3 parts of light stabilizer, 0.3 parts of antioxidant, and 33 parts of solvent.

[0080] in,

[0081] The light stabilizer is a mixture of ultraviolet absorber and hindered amine light stabilizer in a mass ratio of 2:1; the ultraviolet absorber is Tinuvin 400 and the hindered amine light stabilizer is Tinuvin 123.

[0082] The antioxidant is a mixture of hindered phenolic antioxidant and phosphite antioxidant in a 1:1 mass ratio. The hindered phenolic antioxidant is Irganox 1010; the phosphite antioxidant is Irgafos 168.

[0083] The organic solvent is a mixture of propylene glycol methyl ether acetate, propylene glycol methyl ether, and ethyl acetate in a mass ratio of 1:3:1.

[0084] The wetting agent is Twin4100.

[0085] The defoamer is BYK-052.

[0086] The preparation method of high weather-resistant coating includes the following steps:

[0087] (1) Mix acrylic resin, light stabilizer, antioxidant, preservative and bactericide, wetting agent and part of solvent. The mixing speed is 1000-1200 rpm / min and the mixing time is 20 min to obtain a premix.

[0088] (2) Mix the organosilicon modified resin, the premix described in step (1) and the remaining solvent. The mixing speed is 800-1000 rpm / min and the mixing time is 35 min. Then add the defoamer and stir. Adjust the viscosity to 10±1s (25℃, Forecast cup 4). Mix evenly to obtain the final product.

[0089] Example 5

[0090] The difference between Example 5 and Example 1 is that in Example 5, the light stabilizer Tinuvin 400 is replaced with Tinuvin 1130.

[0091] Comparative Example 1

[0092] The difference between Comparative Example 1 and Example 1 is that the organosilicon modified resin in Comparative Example 1 has a mass fraction of 66 parts.

[0093] Comparative Example 2

[0094] The difference between Comparative Example 2 and Example 1 is that the light stabilizer in Comparative Example 2 is a mixture of ultraviolet absorber and hindered amine light stabilizer in a mass ratio of 1:0.8.

[0095] Comparative Example 3

[0096] The difference between Comparative Example 3 and Example 1 is that the light stabilizer in Comparative Example 3 is a mixture of ultraviolet absorber and hindered amine light stabilizer in a mass ratio of 1:1.2.

[0097] Performance testing

[0098] The coatings from Examples 1-5 and Comparative Examples 1-3 were applied to the same type of automotive wood interior trim substrate, and then left to stand at 20-35°C for 2 hours to obtain 12 sets of coatings. The coatings were then baked at 50°C for 48 hours, and the following tests were performed on the coatings:

[0099] I. Heat resistance test:

[0100] The coatings of Examples 1-5 and Comparative Examples 1-3 were subjected to thermal aging at (105±2)℃ for 500 hours, and the yellowing phenomenon on their surfaces was observed. The test results required that there were no defects such as cracks, bubbles, wrinkles, peeling, deformation, or delamination, and the color change level was ≥4. Specific data are shown in Table 1.

[0101] II. Alternating Damp Heat Test:

[0102] Samples from Examples 1-5 and Comparative Examples 1-3 were tested under the following conditions. The test results were required to show no defects such as cracks, bubbles, wrinkles, peeling, deformation, or delamination. Adhesion: 0-1 grade; Scratch resistance: no peeling or cracking of paint to the substrate. Scratches are not allowed (scratches are permissible). Discoloration grade: ≥4 grade. Specific data are shown in Table 1.

[0103] The test procedure and test duration shall be carried out in accordance with the following requirements.

[0104] 15.5h / 100℃→0.5h / 23℃→7.5h / -40℃→0.5h / 23℃→15.5h / 55℃ / 95%→0.5h / 23℃→7.5h / -40℃→0.5h / 23℃ (The above procedure is one cycle).

[0105] 1) Temperature and humidity:

[0106] High temperature: 90℃±2℃

[0107] Low temperature: -40℃±2℃

[0108] High temperature and high humidity: 55℃±2℃ / 95%RH

[0109] 2) Number of loops: 5 loops

[0110] After the test, the sample was placed at room temperature for 1 hour before being inspected.

[0111] III. Scratch Resistance Test:

[0112] The samples from Examples 1-5 and Comparative Examples 1-3 were placed under the following conditions for testing. The test results required that the paint did not peel off or crack from the substrate. Scratches were not allowed (a few scratches were permitted). Specific data are shown in Table 1. The test requirements are as follows:

[0113] 1) Operating force: 10N

[0114] 2) Before the test, place the sample at (23±2)℃ and (50±5)% relative humidity for at least 16 hours. Use automated equipment to make parallel scratches at least 40×40 mm long every 2 mm on an area of ​​1600 mm2. Each scratch is generated by a single movement in one direction.

[0115] 3) Scratching speed: V = 1000 mm / min

[0116] 4) Scratch spacing: 2mm

[0117] 5) Scribing needle: φ1mm

[0118] IV. Chemical resistance, abrasion resistance, and drop test:

[0119] The coatings of Examples 1-5 and Comparative Examples 1-3 were subjected to the following tests using the following reagents, respectively. The test results required that the surface be free of residual reagents after cleaning, and free of defects such as cracks, blistering, wrinkling, and peeling. Adhesion: 0-1 grade. Discoloration grade ≥4 grade. Scratch resistance: No peeling or cracking from the paint to the substrate. Scratches are not allowed (scratches are permitted). The blistering grade after the sunscreen resistance test should be ≥8MD. Specific data are shown in Table 1.

[0120] A. Dry cloth abrasion resistance: 100 cycles of abrasion resistance and color fading test were conducted using dry cloth;

[0121] B. Abrasion resistance of wet cloth: 100 abrasion resistance tests were conducted using a wet cloth (distilled water);

[0122] C. Abrasion resistance to detergents: with 5% surfactant ( The dishwashing liquid underwent 10 abrasion resistance color fading tests.

[0123] Amino alcohol cleaning solution ( The glass cleaner underwent 10 abrasion resistance and color fading tests.

[0124] D. Resistance to organic solvents and abrasion resistance: 10 abrasion resistance color fading tests were conducted using petroleum ether (boiling point range: 80℃-100℃);

[0125] Ten abrasion resistance color fading tests were conducted using denatured alcohol (99% ethanol, 1% methyl ethyl ketone).

[0126] E. Sweat resistance and abrasion resistance: Ten abrasion resistance and color fading tests were conducted using synthetic sweat A [acetic acid with a volume ratio of 0.75% (7.5 mL of 100% acetic acid was diluted with distilled water to 1 L)].

[0127] Ten abrasion resistance color fading tests were conducted using synthetic sweat B [ammonia solution: (1g NH3 solution + 3.47g NaCl + 690mL water)].

[0128] 5. Photoaging resistance:

[0129] Xenon lamp aging tests were conducted on the coatings of Examples 1-5 and Comparative Examples 1-3, respectively, referring to the Volkswagen PV1303-2015 Xenon Arc Aging Test for Automotive Interior Components. The total test time was 125 cycles (600 hours). The test results were required to be: gloss loss ≤1, chalking 0, cracking 0 (so), blistering 10, peeling 0 (so), mold growth 0 (so), spots 0 (so), gold efflorescence 0, pinholes ≤1, no orange peel effect, discoloration ≥4, and adhesion ≤1. Specific data are shown in Table 1. The test conditions were as follows: TYPES BORO / SODA LIME internal / external filters; 228 min illumination period, irradiance (1.2±0.02) W / m².nm @ 420 nm, blackboard temperature (89±3)℃, test chamber temperature (62±2)℃, relative humidity (50±5)%; 60 min darkness period, blackboard temperature (38±3)℃, test chamber temperature (38±3)℃, relative humidity (95±5)%; after the test, color change was evaluated according to GB / T250-2008. Specific data are shown in Table 1.

[0130] Table 1 Test results of each group of samples

[0131]

[0132] Comparing the performance test results of the embodiments and comparative examples in Table 1 above, we can see that:

[0133] (1) From Examples 1-5: Within the range of raw material components and proportions for coating preparation as defined in this invention, the coating has good weather resistance: high temperature resistance and light aging resistance both pass the test; and it has good abrasion resistance. After being treated with dry cloth, wet cloth, cleaning liquid, organic solvent and synthetic sweat and subjected to 100 rubbing color fading tests, its appearance has no visible changes, and its adhesion still passes the test; in addition, it also has good scratch resistance and low temperature impact resistance.

[0134] (2) As can be seen from Examples 1, 2-3 and Comparative Example 1, the effect is best when the weight of silicone modified resin is 50-65 parts, and the heat aging resistance of the coating after spraying and curing is further improved; when the weight of silicone modified resin exceeds 65 parts, the adhesion performance decreases; further increasing the amount of silicone modified resin significantly affects the scratch resistance of the coating, and the low temperature impact resistance cannot pass the test; however, when the weight of silicone modified resin is less than 50 parts, the coating also cannot pass the high temperature resistance and light aging resistance tests.

[0135] (3) As can be seen from Example 1 and Comparative Examples 2-3, only the synergistic effect of a specific mass ratio of ultraviolet light absorber and hindered amine light stabilizer can ensure both the resistance to photoaging and the scratch resistance of the coating formed by the paint. If the proportion of hindered amine light stabilizer is too high, the scratch resistance will not meet the requirements; if it is too low, the resistance to photoaging will fail the test.

[0136] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. The application of a high weather-resistant coating in the preparation of automotive wood interior coatings, characterized in that, The high weather-resistant coating comprises the following raw materials in parts by weight: 50-65 parts of organosilicon modified resin, 5-15 parts of acrylic resin, 2-5 parts of preservative and bactericide, 0.5-2 parts of wetting agent, 0.1-0.5 parts of defoamer, 1-3 parts of light stabilizer, 0.3-1 parts of antioxidant, and 10-35 parts of organic solvent. The silicone-modified resin is designated SH9604A; the acrylic resin is an oil-based acrylic resin; the preservative and bactericide is dimethyloldimethylhydantoin; the light stabilizer is a mixture of benzotriazole UV absorber and hindered amine light stabilizer in a mass ratio of 2:1; the antioxidant is a mixture of hindered phenolic antioxidant and phosphite antioxidant in a mass ratio of 1:1; the organic solvent is a mixture of propylene glycol methyl ether acetate, propylene glycol methyl ether, and ethyl acetate; the high weather-resistant coating has a viscosity of 10±1s, and the test conditions are 25℃ and four-cup coating.

2. The application according to claim 1, characterized in that, The high weather-resistant coating is prepared by the following method: (1) Mix acrylic resin, light stabilizer, antioxidant, preservative and bactericide, wetting agent and some organic solvent to obtain a premix; (2) Mix the organosilicon modified resin, the premix described in step (1) and the remaining organic solvent, then add defoamer and stir. After adjusting the viscosity, filter through a 400-mesh filter to obtain the high weather-resistant coating.

3. The application according to claim 2, characterized in that, In step (1), the mixing speed is 1000-1200 rpm / min and the mixing time is 15-30 min; in step (2), the mixing speed is 800-1000 rpm / min and the mixing time is 30-40 min.

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