An anti-fog coating for vehicle-mounted cameras and its preparation method

Abstract

This application relates to the field of coating layers, and particularly to an anti-fog coating for vehicle-mounted cameras. The anti-fog coating for vehicle-mounted cameras, by mass parts, comprises the following raw materials: 45-60 parts of resin material, 10-20 parts of methyl vinyl silicone rubber, 10-15 parts of microcapsule agent, 20-35 parts of humidity control powder, 15-25 parts of functional filler, 5-10 parts of crosslinking monomer, 3-5 parts of crosslinking assistant, 5-8 parts of foaming agent, 3-4 parts of antibacterial agent, 2-4 parts of ultraviolet resistance agent, 1-2 parts of initiator, 2-4 parts of catalyst, and 8-15 parts of assistant. The anti-fog coating for vehicle-mounted cameras provided by this application not only has excellent anti-fog performance, but also ensures good performance such as aging and corrosion resistance, and can guarantee its performance stability in a long-term high-temperature and high-humidity environment, avoiding the moisture absorption saturation phenomenon of the existing anti-fog coating in a long-term high-temperature and high-humidity environment, and ensuring its anti-condensation effect under normal use conditions.

Description

Technical Field

[0001] This application relates to the field of coating layers, and particularly to an anti-fog coating for vehicle-mounted cameras and a preparation method thereof. Background Art

[0002] With the rapid development of road traffic vehicles in recent years, especially the motor vehicle industries such as new energy vehicles and trains, the development of vehicle-mounted cameras has shown a rapid trend in recent years. And with the continuous progress of driverless technologies, including the full-automatic operation technologies of train vehicles with high automation levels such as GoA3 and GoA4, vehicle-mounted cameras have become one of the key sensors. Whether in rainy days, snowy days, foggy days or at night, road traffic vehicles, including driverless cars and urban rail transit trains, will need to rely on advanced sensors with cameras, such as anti-collision image sensors, speed measurement sensors, pantograph monitoring, and intelligent algorithms to perceive and analyze environmental information to make decisions to achieve better safe operation conditions. Therefore, these sensors are crucial for accurately detecting obstacles and road conditions during the driving of urban rail transit trains and driverless vehicles, enabling vehicles such as trains and cars to drive safely.

[0003] The problem of fogging on vehicle-mounted cameras has an obvious impact on the driverless systems of vehicles and the urban rail transit signal systems. First of all, fogging will lead to a decline in the image quality of the camera, restricting the perception ability of the driverless system for environmental information such as roads, signs, and obstacles, and restricting the monitoring ability of the full-automatic operation system of the train for the environmental information beside the track and the operation conditions of train equipment, which may lead to misjudgment and delayed decision-making, increasing the risk of accidents. Secondly, the difficulty of object detection is a problem. After the camera fogs up, the edges and details cannot be clearly recognized, affecting the object detection and recognition ability, and thus affecting the decision-making and obstacle avoidance ability of driverless train vehicles or car vehicles. Therefore, ensuring the cleanliness and normal working state of vehicle-mounted cameras and adopting appropriate anti-fog measures are important means to ensure the safety and reliability of driverless systems such as trains and cars. As a technical means that can effectively ensure the cleanliness of vehicle-mounted cameras, the anti-fog coating for vehicle-mounted cameras has received extensive attention in recent years. It can effectively achieve the sealing, humidity control, and protection of vehicle-mounted cameras, effectively reducing the possibility of fogging inside and outside the camera to ensure the reliability and clarity of the camera.

[0004] A kind of anti-fog coating for vehicle-mounted cameras provided in this application not only has excellent anti-fog performance, but also ensures its good aging resistance, corrosion resistance and mechanical properties, and can ensure its performance stability in a long-term high-temperature and high-humidity environment, avoiding the moisture absorption saturation phenomenon of the existing anti-fog coating in a long-term high-temperature and high-humidity environment, ensuring its anti-condensation effect under normal use conditions, realizing the dynamic balance of the environmental humidity inside the vehicle-mounted camera, playing a role in protecting optical and electronic components within a suitable humidity range, and having a very excellent application prospect. Summary of the Invention

[0005] To solve the above problems, in the first aspect of this application, a kind of anti-fog coating for vehicle-mounted cameras is provided. Calculated by mass parts, the raw materials are: 45 - 60 parts of resin material, 10 - 20 parts of methyl vinyl silicone rubber, 10 - 15 parts of microcapsule agent, 20 - 35 parts of humidity control powder, 15 - 25 parts of functional filler, 5 - 10 parts of cross-linking monomer, 3 - 5 parts of cross-linking assistant, 5 - 8 parts of foaming agent, 3 - 4 parts of antibacterial agent, 2 - 4 parts of ultraviolet resistant agent, 1 - 2 parts of initiator, 2 - 4 parts of catalyst, and 8 - 15 parts of assistant.

[0006] As a preferred scheme, the mass ratio of the resin material, methyl vinyl silicone rubber and cross-linking monomer is (46 - 55):(12 - 18):(5 - 8).

[0007] As a preferred scheme, the mass ratio of the resin material, methyl vinyl silicone rubber and cross-linking monomer is (48 - 52):(14 - 15):(6 - 7).

[0008] As a preferred scheme, the mass ratio of the microcapsule agent, humidity control powder and functional filler is (12 - 14):(22 - 28):(18 - 25).

[0009] As a preferred scheme, the mass ratio of the microcapsule agent, humidity control powder and functional filler is (13 - 14):(24 - 26):(22 - 24).

[0010] As a preferred scheme, the resin material is a composition of hyperbranched polyurethane acrylate resin and polyethylene glycol diacrylate resin.

[0011] As a preferred scheme, the mass ratio of the hyperbranched polyurethane acrylate resin and polyethylene glycol diacrylate resin is (4 - 4.5):(0.9 - 1.3).

[0012] As a preferred scheme, the mass ratio of the hyperbranched polyurethane acrylate resin and polyethylene glycol diacrylate resin is (4 - 4.2):(1 - 1.1).

[0013] As a preferred embodiment, the weight-average molecular weight of the hyperbranched polyurethane acrylate resin is 10,000 to 15,000 Da.

[0014] As a preferred embodiment, the... of the hyperbranched polyurethane acrylate resin.

[0015] As a preferred embodiment, the weight-average molecular weight of the polyethylene glycol diacrylate resin is 600 to 1,000 Da.

[0016] As a preferred embodiment, the viscosity of the methyl vinyl silicone rubber is 1,000 to 1,500 mPa·s at 25 °C.

[0017] As a preferred embodiment, the microcapsule agent is a paraffin-urea formaldehyde resin microcapsule.

[0018] As a preferred embodiment, the humidity control powder is a composition of nano-aluminum oxide, nano-silica gel, calcium chloride, magnesium chloride, and calcium nitrate.

[0019] As a preferred embodiment, the mass ratio of the nano-aluminum oxide, nano-silica gel, calcium chloride, magnesium chloride, and calcium nitrate is (6 - 8):(4 - 4.5):(3 - 3.5):(1 - 2):(1 - 2).

[0020] As a preferred embodiment, the average particle size of the nano-aluminum oxide is 10 to 20 nm.

[0021] As a preferred embodiment, the specific surface area of the nano-silica gel is 400 to 500 m 2 / g.

[0022] As a preferred embodiment, the average particle size of the calcium chloride is 15 to 20 μm.

[0023] As a preferred embodiment, the average particle size of the magnesium chloride is 10 to 15 μm.

[0024] As a preferred embodiment, the average particle size of the calcium nitrate is 20 to 25 μm.

[0025] As a preferred embodiment, the functional filler is a composition of calcium carbonate and modified composite particles.

[0026] As a preferred embodiment, the mass ratio of the calcium carbonate and the modified composite particles is (3 - 4):(1.5 - 2.2).

[0027] As a preferred embodiment, the average particle size of the calcium carbonate is 200 to 300 nm.

[0028] As a preferred embodiment, the method for preparing the modified composite particles comprises the following steps: S1: Add aluminum chloride and titanium dioxide into DMF, perform ultrasonic dispersion for 20 - 30 min at 200 - 250 W, then add citric acid, succinic anhydride and methacryloxy silane coupling agent, raise the temperature to 60 - 70 °C and keep warm for 2 - 3 h, perform centrifugal filtration, wash and dry to obtain pretreated mixed particles; S2: Add the pretreated mixed particles into a mixed solvent of DMF and methanol, add p-aminobenzoic acid and terephthalic acid, stir and react in a sealed reaction kettle at 120 - 140 °C and a rotation speed of 200 - 240 rpm for 16 - 20 h, naturally cool to room temperature after the reaction is completed, perform centrifugal filtration, wash 2 - 3 times in sequence with DMF and methanol in a circulating manner, and dry in vacuum to obtain pre-product particles; S3: Add the pre-product particles and ethanol into deionized water, adjust the pH to 10 - 10.5 with ammonia water, add tetraethyl orthosilicate and triethanolamine, raise the temperature to 60 - 65 °C and keep warm for 1 - 1.5 h, after completion, wash 2 - 3 times with deionized water in a circulating manner, and dry in vacuum to obtain the product.

[0029] As a preferred embodiment, the mass ratio of the aluminum chloride, titanium dioxide, citric acid, succinic anhydride and methacryloxy silane coupling agent is (5 - 5.5):(0.6 - 1):(0.5 - 0.7):(2 - 2.2):(0.2 - 0.3).

[0030] As a preferred embodiment, in the mixed solvent of DMF and methanol in S2, the mass ratio of DMF to methanol is (3 - 4):1.

[0031] As a preferred embodiment, the mass ratio of the pretreated mixed particles, p-aminobenzoic acid and terephthalic acid is (3 - 3.2):(2.1 - 2.4):(0.5 - 0.8).

[0032] As a preferred embodiment, the mass ratio of the pre-product particles, tetraethyl orthosilicate and triethanolamine is (3.6 - 4):(0.4 - 0.6):(0.05 - 0.1).

[0033] As a preferred embodiment, the average particle size of the titanium dioxide is 5 - 10 nm.

[0034] As a preferred embodiment, the average particle size of the modified composite particles is 420 - 550 nm.

[0035] In this application, the addition of the above-mentioned modified composite particles can effectively improve the high-temperature resistance, corrosion resistance, mechanical and other properties of the anti-fog coating. In particular, it can maintain good performance stability in a long-term high-temperature and high-humidity environment and continuously maintain excellent anti-condensation effect at room temperature. The modified composite particles prepared in this application coordinate and embed titanium dioxide particles on the surface of the adsorption framework particles, thereby forming a composite structure with multiple titanium dioxide particles coating the framework particles. The existence of this structure can first utilize the multiple active groups on the surface of titanium dioxide to form good hydrogen bonds or intermolecular force fixing effects with the organic resin in the coating system, and then achieve its good dispersion effect, reduce the pore diameter of the particles, provide good support for the mechanical properties of the coating system, and ensure a good action environment system for other functions.

[0036] Secondly, the formed composite structure can use the surface titanium dioxide as a good guiding carrier. At room temperature, it can be a good guiding carrier for water molecules. When inside the coating, it can assist in absorbing the water molecules inside the coating. When on the surface, while adsorbing water molecules, it can form a rough continuous peak-valley structure on the coating surface, thereby greatly increasing the surface energy of the coating, effectively enhancing the aggregation of water molecules on the coating surface, and increasing the probability of forming a continuous hydrated layer on the coating surface.

[0037] Finally, the framework particles located at the center of the composite structure can desorb water molecules at high temperatures through amino groups and their own adsorption characteristics, so as to maintain a low moisture absorption level in a high-temperature and high-humidity environment. When the environmental temperature drops below the critical temperature, excellent water molecule adsorption can be realized again, thereby avoiding the phenomenon of moisture absorption saturation of the existing anti-fog coating in a high-temperature and high-humidity environment.

[0038] As a preferred scheme, the cross-linking monomer is styrene.

[0039] As a preferred scheme, the cross-linking aid is a composition of tetramethylol glycoluril and 1,3-bis(oxiranylmethyl)-5-(2-propenyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione.

[0040] As a preferred scheme, the mass ratio of tetramethylol glycoluril to 1,3-bis(oxiranylmethyl)-5-(2-propenyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione is (3 - 4):(1.5 - 2).

[0041] As a preferred scheme, the mass ratio of tetramethylol glycoluril to 1,3-bis(oxiranylmethyl)-5-(2-propenyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione is (3.4 - 3.8):(1.6 - 1.8).

[0042] In this application, by using the above-mentioned specific crosslinking monomers, the compounding of resin materials such as crosslinking aids and hyperbranched polyurethane acrylate resins can effectively improve the anti-fogging, corrosion resistance and mechanical properties of the prepared coating. The combination of crosslinking aids of tetramethylol glycoluril and 1,3-bis(oxiranylmethyl)-5-(2-propenyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione added in this application can effectively serve as the active molecular chain sites in the styrene-acrylate crosslinking reaction in the system, and then enhance the entanglement degree of the crosslinking sites inside the system after the coating is cured, realize the high-molecular chain intercalation with hyperbranched polyurethane acrylate, and then greatly enhance the intermolecular interaction force between the three-dimensional molecular chain networks inside the coating system, further enhancing the intermolecular tightness, improving the enhancement effect of the humidity control powder and filler particles on the internal steric hindrance, and finally greatly reducing the migration efficiency of water molecules and free active groups in the coating, increasing the penetration resistance and path length of water molecules or active molecules carried by water molecules, and maintaining good anti-fogging and anti-aging corrosion effects.

[0043] On the other hand, the multi-active group structures contained in the added tetramethylol glycoluril and hyperbranched polyurethane acrylate can serve as excellent carriers for the humidity control powder and modified fillers during the formation of the coating system. Especially for the hydrogen bond action and intermolecular attraction on the surface of the modified composite particles and some hygroscopic powders, it can effectively enhance the interaction force between the particles and the resin in the coating, playing a good connection and fixing effect, thereby greatly reducing the pore diameter of the micropores formed by the powder particles and filler particles in the coating system, and then avoiding the negative impact of too large pore diameter on the mechanical properties and anti-fogging properties, and obtaining excellent anti-fogging and anti-aging corrosion assistance enhancement effects.

[0044] As a preferred solution, the foaming agent is azodicarbonamide or azobisisobutyronitrile.

[0045] As a preferred solution, the antibacterial agent is chitosan.

[0046] As a preferred solution, the ultraviolet-resistant agent is at least one of glycidoxypropylcaged polyhedral oligomeric silsesquioxane, 2-(2′-hydroxy-3′,5′-di-tert-butylphenyl)-5-chlorobenzotriazole, and 2-(4′-tert-butylphenyl)-4,6-diphenyl-1,3,5-triazine.

[0047] As a preferred solution, the ultraviolet-resistant agent is glycidoxypropylcaged polyhedral oligomeric silsesquioxane.

[0048] As a preferred embodiment, the initiator is at least one of 2-hydroxy-2-methyl-1-phenylpropan-1-one, 2-hydroxy-2-methyl-1-[4-(2-hydroxyethoxy)phenyl]-1-propanone, or 2,4,6-trimethylbenzoyl-diphenylphosphine oxide.

[0049] As a preferred embodiment, the initiator is 2-hydroxy-2-methyl-1-phenylpropan-1-one.

[0050] As a preferred embodiment, the catalyst is any one of acid catalysts.

[0051] As a preferred embodiment, the catalyst is acetic acid.

[0052] As a preferred embodiment, the additives at least include plasticizers, surfactants, and coupling agents.

[0053] As a preferred embodiment, the mass ratio of the plasticizer, surfactant, and coupling agent is (5-10):(1-3):(2-4).

[0054] As a preferred embodiment, the mass ratio of the plasticizer, surfactant, and coupling agent is (6-8):(1.5-2):(3-3.5).

[0055] As a preferred embodiment, the plasticizer is at least one of white oil, epoxy soybean oil, or naphthenic oil.

[0056] As a preferred embodiment, the plasticizer is white oil.

[0057] As a preferred embodiment, the surfactant is at least one of sodium fatty acid, lauryl alcohol polyoxyethylene ether, or cetearyl alcohol polyoxyethylene ether.

[0058] As a preferred embodiment, the surfactant is sodium fatty acid.

[0059] As a preferred embodiment, the coupling agent is 3-aminopropyltrimethoxysilane or γ-glycidoxypropyltrimethoxysilane.

[0060] As a preferred embodiment, the coupling agent is 3-aminopropyltrimethoxysilane.

[0061] The second aspect of the present application provides a method for preparing the anti-fog coating for the in-vehicle camera, which specifically includes the following steps: S1: Mix the resin material and methyl vinyl silicone rubber in a mixing container, heat up to 50-60 °C, and stir and mix at 200-400 rpm for 40-60 min until uniform to obtain a mixed material; S2: Add the mixed material into a reaction container, add microcapsules, humidity control powder and functional fillers, heat up to 65-70 °C, and stir and mix at 500-600 rpm for 40-60 min until uniform; S3: Then, add a crosslinking monomer, a crosslinking aid, a foaming agent, an antibacterial agent, an ultraviolet-resistant agent, an initiator, a catalyst and an auxiliary agent in sequence. After each addition, continue to keep warm and stir at 65-70 °C and 500-600 rpm for 10-15 min to ensure uniform mixing. After all components are added, transfer them into a vacuum defoaming device and perform defoaming treatment at 70-75 °C for 20-30 min to obtain a mixed coating; S4: Dip the mixed coating on the required surface and irradiate it with ultraviolet light at a power density of 80-120 W / cm² until the coating is completely cured, then it is obtained.

[0062] The beneficial effects of the present application are as follows:

[0063] 1. The anti-fog coating for the in-vehicle camera provided in the present application not only has excellent anti-fog performance, but also ensures its good anti-aging, corrosion resistance and mechanical properties, and can ensure its performance stability in a long-term high-temperature and high-humidity environment, avoiding the moisture absorption saturation phenomenon of the existing anti-fog coating in a long-term high-temperature and high-humidity environment, ensuring the anti-condensation effect under normal use conditions, realizing the dynamic balance of the environmental humidity inside the in-vehicle camera, and playing a role in protecting optical and electronic components within a suitable humidity range, having a very excellent application prospect.

[0064] 2. For the anti-fog coating for the in-vehicle camera provided in the present application, the added modified composite particles coordinate and embed titanium dioxide particles on the surface of the adsorbed framework particles, thereby forming a composite structure with multiple titanium dioxide particles coating the framework particles. The existence of this structure can first utilize the multiple active groups on the surface of titanium dioxide to form good hydrogen bonds or intermolecular force fixing effects with the organic resin in the coating system, thereby realizing its good dispersion effect, reducing the pore diameter of the particle pores, providing good mechanical property support for the coating system, and ensuring a good action environment system for other functions.

[0065] 3. A fog-proof coating for vehicle-mounted cameras provided in the present application. The modified composite particles added therein have framework particles located at the center of the composite structure. Through the amino groups and their own adsorption characteristics, the framework particles can desorb water molecules at high temperatures, so as to maintain a low moisture absorption level in high-temperature and high-humidity environments. When the environmental temperature drops below the critical temperature, excellent water molecule adsorption can be achieved again, thus avoiding the phenomenon of moisture absorption saturation of the existing fog-proof coating in high-temperature and high-humidity environments.

[0066] 4. A fog-proof coating for vehicle-mounted cameras provided in the present application. The tetra(hydroxymethyl)glycoluril and hyperbranched polyurethane acrylate added therein contain multi-active group structures, which can serve as excellent carriers for humidity control powder and modified fillers during the formation of the coating system. In particular, the hydrogen bond action and intermolecular attraction on the surface of the modified composite particles and some moisture absorption powder can effectively enhance the interaction force between the particles and the resin in the coating system, playing a good connection and fixing effect, thereby greatly reducing the pore diameter of the micropores formed by the powder particles and filler particles in the coating system, and thus avoiding the negative impact of too large pore diameters on the mechanical and anti-fog properties, and obtaining excellent anti-fog and aging and corrosion resistance assistance enhancement effects. Specific embodiments

[0067] The technical solutions in the above-mentioned invention content of the present application will be further described and demonstrated in the following specific implementation manners. And the following examples are only actual examples for explaining and interpreting the content of the technical solutions in the specification, and should not limit the scope of the claims to be protected by the present application. All technical products based on the technical solutions described in the invention content of the present application should be covered within the scope to be protected by the present application.

[0068] In the following examples, unless otherwise specified, the raw materials are commercially available products that can be obtained, or can be prepared by methods well-known to those skilled in the art. Example 1

[0069] Example 1 provides a fog-proof coating for vehicle-mounted cameras. By mass, the raw materials are: 50 parts of resin material, 15 parts of methyl vinyl silicone rubber, 13.5 parts of microcapsule agent, 24.8 parts of humidity control powder, 23.2 parts of functional filler, 6.8 parts of cross-linking monomer, 5 parts of cross-linking aid, 6.5 parts of foaming agent, 3.2 parts of antibacterial agent, 3.8 parts of ultraviolet resistance agent, 1.8 parts of initiator, 3.6 parts of catalyst, and 12.4 parts of auxiliary agent.

[0070] The resin material is a composition of hyperbranched polyurethane acrylate resin and polyethylene glycol diacrylate resin, and the mass ratio of the two is 4:1. The weight average molecular weight of the hyperbranched polyurethane acrylate resin is 12000 Da, and it is purchased from the corresponding molecular weight product sold by Dongguan Inoue New Materials Development Co., Ltd.

[0071] The weight-average molecular weight of the polyethylene glycol diacrylate resin is 800 Da, and it is purchased from the corresponding molecular weight model product sold by Zhongshan Dixin Chemical Co., Ltd.

[0072] The viscosity of the methyl vinyl silicone rubber is 1200 mPa·s at 25 °C, and it is purchased from the ELASTOSIL® M 3030 model product sold by Wacker Chemie.

[0073] The microcapsule agent is paraffin-urea formaldehyde resin microcapsules, and it is purchased from the F0 grade product sold by Shanghai Yuyu New Materials Technology Co., Ltd.

[0074] The humidity control powder is a composition of nano-aluminum oxide, nano-silica gel, calcium chloride, magnesium chloride and calcium nitrate, and the mass ratio is 7.5:4:3.5:1.5:1.

[0075] The average particle size of the nano-aluminum oxide is 18 nm; the specific surface area of the nano-silica gel is 484 m 2 / g, and it is purchased from the corresponding specific surface area model product sold by Shanghai Macklin Biochemical Co., Ltd.; the average particle size of calcium chloride is 15 μm, the average particle size of magnesium chloride is 12.5 μm, the average particle size of calcium nitrate is 20 μm, and calcium chloride, magnesium chloride and calcium nitrate are all purchased from the corresponding particle size products sold by Shanghai Macklin Biochemical Co., Ltd.

[0076] The functional filler is a composition of calcium carbonate and modified composite particles, and the mass ratio of the two is 3.2:2.

[0077] The average particle size of the calcium carbonate is 300 nm, and it is purchased from the corresponding particle size model product sold by Shandong Tian'an New Materials Co., Ltd.

[0078] The preparation method of modified composite particles comprises the following steps, calculated by mass: S1: adding 5.4 parts of aluminum chloride and 0.75 parts of titanium dioxide to 200 parts of DMF, ultrasonically dispersing at 240W for 25 minutes, then adding 0.6 parts of citric acid, 2.1 parts of succinic anhydride and 0.22 parts of methacryloxysilane coupling agent, heating to 65°C and keeping warm for 2.5 hours, centrifugally filtering, washing and drying to obtain pretreated mixed particles; S2: adding 3.2 parts of pretreated mixed particles to a mixed solvent of 220 parts of DMF and methanol (the mass ratio of DMF to methanol is 4:1), adding 2 .2 parts of p-aminobenzoic acid and 0.6 parts of terephthalic acid are stirred in a sealed reactor at 125°C and 200rpm for 18 hours. After the reaction is completed, it is naturally cooled to room temperature, centrifuged, washed with DMF and methanol for 3 times in a cycle, and vacuum dried to obtain pre-product particles; S3: 3.8 parts of pre-product particles and 10 parts of ethanol are added to 120 parts of deionized water, the pH is adjusted to 10.2 with ammonia water, 0.55 parts of tetraethyl orthosilicate and 0.08 parts of triethanolamine are added, the temperature is raised to 64°C and kept warm for 1.2 hours. After completion, the deionized water is washed for 3 times in a cycle, and vacuum dried to obtain.

[0079] The average particle size of titanium dioxide is 5 nm; the average particle size of the modified composite particles is 517 nm.

[0080] The cross-linking monomer is styrene; the cross-linking auxiliary agent is a composition of tetramethylol glycoluril and 1,3-bis(oxiranylmethyl)-5-(2-propenyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione, and the mass ratio of the two is 3.5:1.8.

[0081] The foaming agent is azodicarbonamide; the antibacterial agent is chitosan, which is a food-grade antibacterial chitosan product purchased from Zhejiang Yicun Biotechnology Co., Ltd.

[0082] The UV-resistant agent is glycidyl ether oxypropyl cage-type polysilsesquioxane, which is a high-purity GR product purchased from Xi'an Qiyue Biotechnology Co., Ltd.

[0083] The initiator is 2-hydroxy-2-methyl-1-phenylpropan-1-one; and the catalyst is acetic acid.

[0084] The additives are plasticizer, surfactant and coupling agent, and the mass ratio of the three is 6.5:2:3.

[0085] The plasticizer is white oil #5; the surfactant is sodium fatty acid; and the coupling agent is 3-aminopropyltrimethoxysilane.

[0086] In the second aspect of this embodiment, a method for preparing the above anti-fog coating for vehicle-mounted cameras is provided, which specifically includes the following steps: S1: Mix the resin material and methyl vinyl silicone rubber in a mixing container, heat up to 60°C, and stir and mix at 300 rpm for 50 min until uniform to obtain a mixed material; S2: Add the mixed material to a reaction container, add microcapsules, humidity control powder, and functional fillers, heat up to 70°C, and stir and mix at 550 rpm for 45 min until uniform; S3: Then, add crosslinking monomers, crosslinking aids, foaming agents, antibacterial agents, UV-resistant agents, initiators, catalysts, and additives in sequence. After each addition, continue to keep warm and stir at 70°C and 550 rpm for 12 min to ensure uniform mixing. After all components are added, transfer to a vacuum degassing device and perform degassing treatment at 75°C for 25 min to obtain a mixed coating; S4: Dip the mixed coating on the required surface and irradiate it with ultraviolet light at a power density of 100 W / cm² until the coating is completely cured, and then it is obtained. Example 2

[0087] The specific implementation manner of this embodiment is basically the same as that of Example 1, except that: for the anti-fog coating for vehicle-mounted cameras, in parts by mass, the raw materials are: 55 parts of resin material, 12 parts of methyl vinyl silicone rubber, 12.2 parts of microcapsules, 28 parts of humidity control powder, 18 parts of functional fillers, 8 parts of crosslinking monomers, 5 parts of crosslinking aids, 6.5 parts of foaming agents, 3.2 parts of antibacterial agents, 3.8 parts of UV-resistant agents, 1.8 parts of initiators, 3.6 parts of catalysts, and 12.4 parts of additives.

[0088] The resin material is a composition of hyperbranched polyurethane acrylate resin and polyethylene glycol diacrylate resin, and the mass ratio of the two is 4.5:0.9.

[0089] The humidity control powder is a composition of nano-aluminum oxide, nano-silica gel, calcium chloride, magnesium chloride, and calcium nitrate, and the mass ratio is 6:4.5:3:1:1.5.

[0090] The functional filler is a composition of calcium carbonate and modified composite particles, and the mass ratio of the two is 4:1.5.

[0091] The additive is a plasticizer, a surfactant, and a coupling agent, and the mass ratio of the three is 8:1.5:3.5. Example 3

[0092] The specific implementation of this embodiment is basically the same as that of Embodiment 1, except that: for the anti-fog coating of the vehicle-mounted camera, by mass, the raw materials are: 46 parts of resin material, 18 parts of methyl vinyl silicone rubber, 14 parts of microcapsule agent, 22 parts of humidity control powder, 25 parts of functional filler, 5 parts of crosslinking monomer, 5 parts of crosslinking assistant, 6.5 parts of foaming agent, 3.2 parts of antibacterial agent, 3.8 parts of ultraviolet-resistant agent, 1.8 parts of initiator, 3.6 parts of catalyst, and 12.4 parts of assistant.

[0093] The resin material is a composition of hyperbranched polyurethane acrylate resin and polyethylene glycol diacrylate resin, and the mass ratio of the two is 4:1.3.

[0094] The humidity control powder is a composition of nano-aluminum oxide, nano-silica gel, calcium chloride, magnesium chloride and calcium nitrate, and the mass ratio is 8:4:3.5:2:2.

[0095] The functional filler is a composition of calcium carbonate and modified composite particles, and the mass ratio of the two is 3:2.2.

[0096] The assistant is a plasticizer, a surfactant and a coupling agent, and the mass ratio of the three is 5:2.5:2.

[0097] Comparative Example 1

[0098] The specific implementation of this comparative example is basically the same as that of Embodiment 1, except that: for the anti-fog coating of the vehicle-mounted camera, by mass, the raw materials are: 65 parts of resin material, 8 parts of methyl vinyl silicone rubber, 8.8 parts of microcapsule agent, 28.6 parts of humidity control powder, 15.2 parts of functional filler, 2.5 parts of crosslinking monomer, 5 parts of crosslinking assistant, 6.5 parts of foaming agent, 3.2 parts of antibacterial agent, 3.8 parts of ultraviolet-resistant agent, 1.8 parts of initiator, 3.6 parts of catalyst, and 12.4 parts of assistant.

[0099] Comparative Example 2

[0100] The specific implementation of this comparative example is basically the same as that of Embodiment 1, except that: for the anti-fog coating of the vehicle-mounted camera, by mass, the raw materials are: 40 parts of resin material, 20 parts of methyl vinyl silicone rubber, 5.5 parts of microcapsule agent, 15.2 parts of humidity control powder, 35.5 parts of functional filler, 6.8 parts of crosslinking monomer, 5 parts of crosslinking assistant, 6.5 parts of foaming agent, 3.2 parts of antibacterial agent, 3.8 parts of ultraviolet-resistant agent, 1.8 parts of initiator, 3.6 parts of catalyst, and 12.4 parts of assistant.

[0101] Comparative Example 3

[0102] The specific implementation of this comparative example is basically the same as that of Embodiment 1, except that: the crosslinking monomer is a composition of p-methylstyrene and 2-ethylhexyl acrylate, and the mass ratio of the two is 0.8:2.

[0103] Comparative Example 4

[0104] The specific implementation manner of this comparative example is basically the same as that of Example 1, except that: the crosslinking aid is a composition of tetramethylol glycoluril and 1,3-bis(oxiranylmethyl)-5-(2-propenyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione, and the mass ratio of the two is 4.5:0.4.

[0105] Comparative Example 5

[0106] The specific implementation manner of this comparative example is basically the same as that of Example 1, except that: the crosslinking aid is a composition of tetramethylol glycoluril and 1,3-bis(oxiranylmethyl)-5-(2-propenyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione, and the mass ratio of the two is 1:1.8.

[0107] Comparative Example 6

[0108] The specific implementation manner of this comparative example is basically the same as that of Example 1, except that: the preparation method of the modified composite particles includes the following steps, in parts by mass: S1: Add 8.5 parts of aluminum chloride and 0.35 part of titanium dioxide to 200 parts of DMF, ultrasonically disperse for 25 min at 240 W, then add 0.4 part of citric acid, 1.1 parts of succinic anhydride and 0.1 part of methacryloxy silane coupling agent, heat up to 65 °C and keep warm for 2.5 h, centrifuge and filter, wash and dry to obtain pretreated mixed particles; S2: Add 5.5 parts of pretreated mixed particles to a mixed solvent of 220 parts of DMF and methanol (the mass ratio of DMF to methanol is 4:1), add 2.2 parts of p-aminobenzoic acid and 0.6 part of terephthalic acid, stir and react in a sealed reaction kettle at 125 °C and 200 rpm for 18 h, after the reaction is completed, naturally cool to room temperature, centrifuge and filter, wash 3 times in turn with DMF and methanol, and vacuum dry to obtain pre-product particles; S3: Add 3.8 parts of pre-product particles and 10 parts of ethanol to 120 parts of deionized water, adjust the pH to 10.2 with ammonia water, add 0.55 part of tetraethyl orthosilicate and 0.08 part of triethanolamine, heat up to 64 °C and keep warm for 1.2 h, after completion, wash 3 times with deionized water in circulation, and vacuum dry to obtain the product.

[0109] The average particle size of the modified composite particles is 384 nm.

[0110] Comparative Example 7

[0111] The specific implementation of this comparative example is basically the same as that of Example 1, except that the preparation method of the modified composite particles includes the following steps, in parts by mass: S1: Add 7.5 parts of aluminum chloride and 0.75 parts of titanium dioxide to 200 parts of DMF, disperse ultrasonically at 240 W for 25 min, then add 0.6 parts of citric acid, 2.1 parts of succinic anhydride and 0.22 parts of methacryloxy silane coupling agent, heat up to 65 °C and keep warm for 2.5 h, centrifuge and filter, wash and dry to obtain pretreated mixed particles; S2: Add 1.5 parts of pretreated mixed particles to a mixed solvent of 220 parts of DMF and methanol (the mass ratio of DMF to methanol is 4:1), add 4.5 parts of p-aminobenzoic acid and 2.5 parts of terephthalic acid, stir and react in a sealed reaction kettle at 125 °C and 200 rpm for 18 h, after the reaction is completed, naturally cool to room temperature, centrifuge and filter, wash 3 times in turn with DMF and methanol, dry in vacuum to obtain pre-product particles; S3: Add 3.8 parts of pre-product particles and 10 parts of ethanol to 120 parts of deionized water, adjust the pH to 10.2 with ammonia water, add 1.8 parts of tetraethyl orthosilicate and 0.22 parts of triethanolamine, heat up to 64 °C and keep warm for 1.2 h, after completion, wash 3 times with deionized water in circulation, dry in vacuum to obtain the product.

[0112] The average particle size of the modified composite particles is 675 nm.

[0113] Comparative Example 8

[0114] The specific implementation of this comparative example is basically the same as that of Example 1, except that the average particle size of titanium dioxide is 35 nm; the average particle size of the modified composite particles is 722 nm.

[0115] Performance evaluation

[0116] Bonding performance test: Apply the product to an aluminum plate, after curing is completed, test the overall bonding strength of the coating through a tensile peel tester, and record the average value of 10 tests in Table 1.

[0117] Moisture absorption amount test: Apply the product to a metal plate, after curing is completed, place it in an environment of 25 °C temperature and 96 ± 2% humidity for 24 h, test its weight, calculate the overall moisture absorption amount before and after the test, and record the average value of 10 tests in Table 1.

[0118] High temperature and high humidity test: Apply the product to a metal plate, after curing is completed, put it into a constant temperature and humidity box at 85 ± 3 °C and relative humidity of 75 ± 2% for 1000 h, after completion, observe its surface state. If there are phenomena such as coating peeling, cracking, and yellowing, record it as unqualified, otherwise it is qualified. Test 50 groups of specimens for each group, calculate the qualification rate of each group and record it in Table 1.

[0119] Salt corrosion resistance test: The coatings prepared in the examples and comparative examples were subjected to a corrosion resistance test with 5 wt% NaCl. The coating specimens with a thickness of 1.5 mm were immersed in a 5 wt% NaCl solution for 400 h. After that, the coatings were taken out and observed for cracking, blistering, hydrolysis, and corrosion oxidation. If any of these phenomena occurred, it was recorded as qualified; otherwise, it was unqualified. 50 specimens were tested in each group, and the qualification rate was recorded in Table 1.

[0120] Table 1 Performance test results

[0121] Example Adhesion strength (MPa) <![CDATA[Moisture absorption (g / m 2 ·24 h)]]> Qualified rate of high temperature and high humidity resistance (%) Qualified rate of salt spray corrosion resistance (%) Example 1 1.41 69.9 98 98 Example 2 1.36 67.4 96 94 Example 3 1.39 66.8 98 96 Comparative example 1 1.17 52.3 90 90 Comparative example 2 1.09 54.4 92 92 Comparative example 3 1.11 51.4 88 86 Comparative example 4 1.24 47.1 86 80 Comparative example 5 1.29 48.2 90 82 Comparative example 6 1.25 49.4 82 78 Comparative example 7 1.11 47.9 80 76 Comparative example 8 1.22 46.8 84 80

[0122] From the data results of the examples, comparative examples, and Table 1 of this application, it can be seen that Examples 1-3 of this application have obvious advantages over Comparative Examples 1-8 in terms of adhesion performance, anti-fog performance, high temperature resistance, and corrosion and aging resistance. This is mainly because of the combined action of the defined resin materials, defined crosslinking system solutions, modified composite particles, and other matching solutions added in this application. In contrast, Comparative Examples 1-8 did not adopt the technical solutions defined in this application, resulting in obvious disadvantages in the above performance tests. This further proves the necessity of the defined technical solutions of this application for the technical effects and solving technical problems of this application.

Claims

1. An anti-fog coating for a vehicle-mounted camera, characterized in that: The raw materials are as follows: 45-60 parts of resin, 10-20 parts of methyl vinyl silicone rubber, 10-15 parts of microcapsules, 20-35 parts of moisture control powders, 15-25 parts of functional fillers, 5-10 parts of crosslinking monomers, 3-5 parts of crosslinking aids, 5-8 parts of foaming agents, 3-4 parts of antibacterial agents, 2-4 parts of UV resistant agents, 1-2 parts of initiators, 2-4 parts of catalysts, and 8-15 parts of additives. The resin material is a composite material of a hyperbranched polyurethane acrylate resin with a weight average molecular weight of 10000-15000Da and a polyethylene glycol diacrylate resin with a weight average molecular weight of 600-1000Da in a mass ratio of (4-4.5): (0.9-1.3); The viscosity of methyl vinyl silicone rubber is 1000~1500mPa·s at 25℃; The microcapsule is paraffin-urea-formaldehyde resin microcapsule; The moisture control powder is a composite material of nano-alumina, nano-silica gel, calcium chloride, magnesium chloride and calcium nitrate in a mass ratio of (6-8): (4-4.5): (3-3.5): (1-2): (1-2); the average particle size of the nano-alumina is 10-20 nm; The functional filler is a composite material of calcium carbonate and modified composite particles in a mass ratio of (3-4): (1.5-2.2); The preparation method of the modified composite particles includes: S1: adding aluminum chloride and titanium dioxide to DMF, ultrasonically dispersing at 200-250W for 20-30min, then adding citric acid, succinic anhydride and methacryloyloxysilane coupling agent, heating to 60-70°C and keeping warm for 2-3h, centrifugally filtering, washing and drying to obtain pre-treated mixed particles; S2: adding the pre-treated mixed particles to a mixed solvent of DMF and methanol, adding p-aminobenzoic acid and terephthalic acid, stirring and reacting at 120-140°C and 200-240rpm in a sealed reactor for 16-20h, naturally cooling to room temperature after the reaction is completed, centrifugally filtering, washing with DMF and methanol in a cycle for 2-3 times in sequence, and vacuum drying to obtain pre-product particles; S3: adding the pre-product particles and ethanol to deionized water, adjusting the pH to 10-10.5 with ammonia water, adding ethyl orthosilicate and triethanolamine, heating to 60-65°C and keeping warm for 1-1 .5h, after completion, wash with deionized water for 2-3 times, and dry in vacuum to obtain; The mass ratio of aluminum chloride, titanium dioxide, citric acid, succinic anhydride and methacryloxysilane coupling agent is (5-5.5): (0.6-1): (0.5-0.7): (2-2.2): (0.2-0.3); the mass ratio of pre-treated mixed particles, aminobenzoic acid and terephthalic acid is (3-3.2): (2.1-2.4): (0.5-0.8); The average particle size of titanium dioxide is 5~10nm; the average particle size of modified composite particles is 420~550nm; The cross-linking monomer is styrene; The cross-linking auxiliary agent is a composite material of tetramethylol glycoluril and 1,3-bis(oxiranylmethyl)-5-(2-propylene)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione in a mass ratio of (3-4):(1.5-2); The auxiliary agent is a composite material of a plasticizer, a surfactant and a coupling agent in a mass ratio of (5-10): (1-3): (2-4).

2. The anti-fog coating for a vehicle-mounted camera according to claim 1, characterized in that: The mass ratio of the resin material, methyl vinyl silicone rubber and cross-linking monomer is (46-55): (12-18): (5-8).

3. The anti-fog coating for a vehicle-mounted camera according to claim 2, characterized in that: The mass ratio of the microcapsule, the moisture control powder and the functional filler is (12-14): (22-28): (18-25).

4. The anti-fog coating for a vehicle-mounted camera according to claim 3, characterized in that: The specific surface area of ​​the nano silica gel is 400-500m 2 / g.

5. The anti-fog coating for a vehicle-mounted camera according to claim 4, characterized in that: The mass ratio of the pre-product particles, tetraethyl orthosilicate and triethanolamine is (3.6-4): (0.4-0.6): (0.05-0.1).

6. A method for preparing an anti-fog coating for a vehicle camera according to any one of claims 1 to 5, characterized in that: The specific steps include: S1: Mix the resin material and methyl vinyl silicone rubber in a mixing container, heat it to 50-60°C, stir and mix at 200-400rpm for 40-60min until uniform, and obtain a mixture; S2: Add the mixture to a reaction container, add microcapsules, moisture control powder and functional fillers, heat it to 65-70°C, stir and mix at 500-600rpm for 40-60min until uniform; S3: Then add cross-linking monomer, cross-linking auxiliary agent, foaming agent, antibacterial agent, UV resistant agent, initiator, catalyst and auxiliary agent in sequence, continue to stir at 65-70°C and 500-600rpm for 10-15min after each addition to ensure uniform mixing, and after all ingredients are added, move them into a vacuum degassing device, degassing at 70-75°C for 20-30min, and obtain a mixed coating; S4: Dip-coat the mixed coating on the desired surface and irradiate it with UV light at a power density of 80~120 W / cm² until the coating is completely cured.