Preparation method of anti-fog coating based on cation curing

Abstract

The invention discloses a preparation method of an anti-fog coating based on cationic curing, and aims to provide a cationic curing anti-fog coating which is prepared by uniformly stirring cationic curing organic silicon modified acrylic resin with epoxy resin, adding a certain amount of modified silicon dioxide (SiO2) microspheres, and performing ultraviolet irradiation. The organic silicon modified acrylic resin is adopted, the water resistance, stain resistance, solvent resistance, weather resistance and other properties of the cured film are improved, and the silicon dioxide (SiO2) microspheres reduce the water-oil contact angle of the coating, so that the cured film has good anti-fog performance and is widely applied to automobile windshields, rearview mirrors, medical instruments, spectacle lenses, goggles and the like.

Description

Technical Field

[0001] This invention relates to a method for preparing an anti-fog coating based on cationic curing, belonging to the field of polymer materials technology. Background Technology

[0002] With increased environmental inspections, high-volatile solvent-based coatings face the risk of being completely banned. UV curing technology, characterized by fast drying, energy saving, low VOC emissions, and excellent film performance, has seen rapid development in recent years, and its products are now used in numerous fields. UV curing mainly employs two curing mechanisms: free radical and cationic. Free radical curing systems offer fast curing speeds and easily adjustable product performance, but suffer from issues such as susceptibility to oxygen inhibition, severe polymerization volume shrinkage, low precision, and poor adhesion. In contrast, cationic curing systems are oxygen-resistant, capable of thick film curing, exhibit minimal volume shrinkage, strong adhesion, wear resistance, and high hardness, leading to a gradual increase in their application scenarios and usage.

[0003] In recent years, the development of anti-fog coatings has been very rapid. In applications such as eyeglasses, swimming goggles, bathroom mirrors, car windshields, medical goggles, and face masks, it is necessary to prevent water vapor from condensing into small droplets on the surface to maintain transparency. Therefore, there is a need to develop anti-fog coatings suitable for these applications. Currently, commercially available anti-fog coatings have poor anti-fog performance, short lifespan, and limited application scenarios, which seriously restricts the development of anti-fog coatings. Summary of the Invention

[0004] Purpose of the Invention: The purpose of this invention is to provide a cationically curable organosilicon-modified acrylic resin. After being uniformly stirred with epoxy resin, a certain amount of modified silica (SiO2) microspheres are added. Upon ultraviolet irradiation, a cationically cured antifog coating is obtained. The cured film of this coating exhibits properties such as water resistance, stain resistance, solvent resistance, and weather resistance. The silica (SiO2) microspheres significantly reduce the water-oil contact angle of the coating, giving the cured film excellent antifog performance. It has wide applications in automotive windshields, rearview mirrors, medical devices, eyeglass lenses, and goggles.

[0005] The technical solution adopted in this invention is: A method for preparing an anti-fogging coating based on cationic curing includes the following steps: (1) Preparation of organosilicon modified acrylic resin: Add organic solvent to a flask, heat up, mix organosilicon, alkyl acrylate or alkyl methacrylate, initiator and slowly add dropwise to a three-necked flask after uniform mixing. After the addition is completed, continue to keep warm, and recover the organic solvent by vacuum distillation to obtain organosilicon modified acrylic resin. (2) Preparation of silica microspheres: Add solvent and alkaline water to a three-necked flask, then add tetraethyl orthosilicate under stirring. Stir the mixture at room temperature, centrifuge the product with a high-speed centrifuge, wash the product with solvent, and dry it to obtain silica microspheres. (3) Preparation of antifog coating: The organosilicon modified acrylic resin obtained in step (1), the silica microspheres obtained in step (2), epoxy resin, reactive diluent, chain extender, defoamer, leveling agent and photoinitiator are cured into a film after being irradiated by ultraviolet lamp.

[0006] As a preferred embodiment, the above-described method for preparing an anti-fog coating based on cationic curing includes the following steps: (1) Preparation of organosilicon modified acrylic resin: Add 100-400 parts by weight of organic solvent to a three-necked flask equipped with a stirrer and thermometer, heat to 90-110℃, and slowly add 15-30 parts by weight of organosilicon, 70-85 parts by weight of alkyl acrylate or alkyl methacrylate, and 3-5 parts by weight of initiator to the three-necked flask after mixing evenly. The addition time is 2-4 h. After the addition is completed, continue to keep warm for 6-10 h. The organic solvent is recovered by vacuum distillation. Organosilicon modified acrylic resin is obtained in the three-necked flask.

[0007] (2) Preparation of silica (SiO2) microspheres: 100-200 parts by weight of solvent and 15-50 parts by weight of alkaline water were added to a three-necked flask equipped with a stirrer, and then 10-50 parts by weight of tetraethyl orthosilicate were added under stirring. The mixture was stirred at room temperature for 24-72 h. After centrifugation with a high-speed centrifuge, the product was washed three times with solvent and then dried in an oven at 50℃ for 24-48 h to obtain silica microspheres. The surface of these silica microspheres is covered with a large number of hydroxyl groups, which have good hydrophilicity.

[0008] (3) Preparation of antifog coating: 60-90 parts by weight of silicone-modified acrylic resin obtained in step (1), 3-10 parts by weight of silica (SiO2) microspheres obtained in step (2), 10-30 parts by weight of epoxy resin, 5-30 parts by weight of reactive diluent, 3-10 parts by weight of chain extender, 0.5-2.5 parts by weight of defoamer, 0.2-1.5 parts by weight of leveling agent and 3-5 parts by weight of photoinitiator.

[0009] As a preferred embodiment, in the above-described method for preparing an antifog coating based on cationic curing, the solvent in step (1) is at least one or a mixture of several of the following: toluene, ethyl acetate, isooctyl acetate, butanone, chloroform, xylene, petroleum ether, and DMF; and the organosiloxane is at least one or a mixture of several of the following: vinyltrimethoxysilane, vinyltri-β-methoxyethoxysilane, vinyldimethylethoxysilane, and vinyltriethoxysilane. Alkyl acrylates or alkyl methacrylates are: methyl methacrylate, methyl acrylate, propyl methacrylate, propyl acrylate, butyl methacrylate, butyl acrylate, isobutyl methacrylate, isobutyl acrylate, isoamyl methacrylate, isoamyl acrylate, hexyl methacrylate, hexyl acrylate, hydroxyethyl acrylate (HEA), hydroxyethyl methacrylate (HEMA), hydroxypropyl acrylate (HPA), hydroxypropyl methacrylate (HPMA), tetrahydrofurfuryl acrylate, glycidyl methacrylate, diethylene glycol divinyl ether, 4-hydroxybutyl vinyl ether, or a mixture of at least one or more of these. The initiator is a mixture of at least one or more of the following: azo compounds, organic peroxides, and redox systems.

[0010] Preferably, in step (2) of the present invention, the solvent is a mixture of at least one or more of toluene, xylene, ethanol, and acetone; the alkaline water is a mixture of at least one or more of ammonia water (5-20% by mass), sodium carbonate solution (5-20% by mass), sodium hydroxide solution (2-20% by mass), triethylamine, and diethanolamine; the centrifuge requirements are: rotation speed 1000-2000 r / min, time 10-20 min.

[0011] Preferably, in step (3) of the present invention, the epoxy resin is a mixture of at least one or more of linear alicyclic and aromatic epoxy resins; the reactive diluent is a mixture of at least one or more of KH-560 silane coupling agent, 4-vinylepoxycyclohexane, 3,4-epoxycyclohexylmethyl 3,4-epoxycyclohexylcarboxylate, 3-hydroxymethyl-3-ethyloxetane, 3-benzyloxymethyl-3-ethyloxetane, 3-ethyl-3-(phenoxymethyloxy)heptacyclic butane, 3-ethyl-3-(octoxymethyl)oxetane, and tetrahydroindene diepoxide; and the chain extender is a mixture of at least one or more of diethylene glycol divinyl ether and triethylene glycol divinyl ether. The defoamer is a mixture of at least one or more of the following: organosilicon, organofluorine, and high-molecular-weight organosilicon; the leveling agent is a mixture of at least one or more of the following: acrylate and epoxy leveling agents. The cationic photoinitiator is at least one or a mixture of several of the following: triarylhexafluoroantimony thioonium salt, diaryliodoonium hexafluorophosphate, dialkylbenzoylmethyl thioonium salt, dialkyl-4-hydroxyphenyl thioonium salt, didodecylbenzeneiodoonium salt, diaryliodoonium phosphate, and triaryliodoonium phosphate.

[0012] The beneficial effects of this invention are as follows: This invention provides a novel cationic curable silicone-modified epoxy acrylate. After curing with epoxy resin under ultraviolet light, the coating film exhibits excellent mechanical properties, solvent resistance, high adhesion, and good light transmittance. The silica (SiO2) microspheres provide good hydrophilicity to the overall coating film, resulting in a highly hydrophilic coating surface. This promotes the uniform spread of condensate into a transparent water film rather than dispersed droplets, reducing light scattering and emphasizing transparency maintenance. It also provides excellent anti-fogging performance and is suitable for visually sensitive scenarios. Future applications and prospects are expected to expand further. Detailed Implementation

[0013] The present invention will be further described below with reference to embodiments, but the embodiments do not constitute a limitation on the scope of protection of the present invention.

[0014] Example 1 A method for preparing an anti-fogging coating based on cationic curing includes the following steps: (1) Preparation of organosilicon-modified acrylic resin: By mass, 150 parts by mass of toluene were added to a three-necked flask equipped with a stirrer and a thermometer, and the temperature was raised to 95°C. 5 parts by mass of vinyltrimethoxysilane, 5 parts by mass of vinyldimethylethoxysilane, 10 parts by mass of vinyltriethoxysilane, 5 parts by mass of methyl methacrylate, 3 parts by mass of propyl acrylate, 5 parts by mass of butyl methacrylate, 3 parts by mass of hydroxyethyl acrylate (HEA), 5 parts by mass of hydroxyethyl methacrylate (HEMA), 5 parts by mass of hydroxypropyl acrylate (HPA), 5 parts by mass of hydroxypropyl methacrylate (HPMA), 5 parts by mass of tetrahydrofurfuryl acrylate, 40 parts by mass of glycidyl methacrylate, and 3 parts by mass of azobisisobutyronitrile were mixed evenly and then slowly added dropwise to the three-necked flask. The addition time was 2 h. After the addition was completed, the temperature was maintained for 10 h. The organic solvent was recovered by vacuum distillation, and organosilicon-modified acrylic resin was obtained in the three-necked flask.

[0015] (2) Preparation of silica (SiO2) microspheres: 100 parts by mass of ethanol and 15 parts by mass of 20% ammonia solution were added to a three-necked flask equipped with a stirrer, and then 15 parts by mass of tetraethyl orthosilicate were added under stirring. The mixture was stirred at room temperature for 24 h. After centrifuging the product by high-speed centrifugation (1000 r / min, centrifugation for 10 min), the product was washed three times with solvent and then dried in an oven at 50 °C for 24 h to obtain silica microspheres. The surface of these silica microspheres is covered with a large number of hydroxyl groups, which have good hydrophilicity.

[0016] (3) Preparation of antifog coating: 60 parts by mass of silicone modified acrylic resin obtained in step (1), 3 parts by mass of silica (SiO2) microspheres obtained in step (2), 10 parts by mass of epoxy resin E-51, 19 parts by mass of KH-560 silane coupling agent, 5 parts by mass of 4-vinylepoxycyclohexane, 3 parts by mass of 3,4-epoxycyclohexylmethyl 3,4-epoxycyclohexyl carboxylate, 3 parts by mass of 3-hydroxymethyl-3-ethyloxetane reactive diluent, 3 parts by mass of chain extender diethylene glycol divinyl ether, 0.5 parts by mass of defoamer BYK350, 0.2 parts by mass of leveling agent EFKA 3777 and 3 parts by mass of photoinitiator bis(dodecylbenzeneiodonium) salt, were finally cured into a film by a crawler-type curing machine.

[0017] 2. Performance Testing The pencil hardness of the coating was tested according to the national standard GBT-6739. According to GB / 9286-1998, adhesion is tested. Grade 0 indicates no peeling and the strongest adhesion. Grade 1 indicates slight peeling at the edges. Grade 2 indicates that the peeling is more severe than Grade 1. The water resistance of the membrane was determined according to GB / 1733-1993; the transmittance of the membrane was tested using ultraviolet light with a wavelength of 380 nm. The abrasion resistance of the membrane was tested according to GB / T 15036.2 standard; the membrane was washed 200 times with acetone solution to observe its abrasion resistance. Elongation at break: The elongation at break, determined by tensile testing, can, to some extent, indicate the toughness of the material. Coatings with higher elongation at break have better toughness. The performance is shown in Table 1 below. Table 1 Performance Test Results project Water resistance No whitening after soaking for a week hardness 5H Light transmittance 92 wear-resistant WR3 Washable No change Adhesion / Grade 0 Elongation at break 21.24 Water contact angle 14.2° Oil contact angle 22.4° .

[0018] Example 2 A method for preparing an anti-fogging coating based on cationic curing includes the following steps: (1) Preparation of organosilicon-modified acrylic resin: By mass, 200 parts by mass of xylene were added to a three-necked flask equipped with a stirrer and a thermometer, and the temperature was raised to 120°C. 10 parts by mass of vinyldimethylethoxysilane, 15 parts by mass of vinyltriethoxysilane, 3 parts by mass of propyl acrylate, 5 parts by mass of butyl methacrylate, 9 parts by mass of hydroxyethyl methacrylate (HEMA), 5 parts by mass of hydroxypropyl acrylate (HPA), 5 parts by mass of tetrahydrofurfuryl acrylate, 50 parts by mass of glycidyl methacrylate, and 5 parts by mass of azobisisobutyronitrile were mixed evenly and then slowly added dropwise to the three-necked flask. The addition time was 3 h. After the addition was completed, the temperature was maintained for another 8 h. The organic solvent was recovered by vacuum distillation, and organosilicon-modified acrylic resin was obtained in the three-necked flask.

[0019] (2) Preparation of silica (SiO2) microspheres: 100 parts by mass of toluene and 25 parts by mass of 10% ammonia solution were added to a three-necked flask equipped with a stirrer, and then 25 parts by mass of tetraethyl orthosilicate were added under stirring. The mixture was stirred at room temperature for 24 h. The product was centrifuged at high speed (1000 r / min, centrifugation for 20 min), and then washed three times with solvent. After drying in an oven at 50 °C for 24 h, silica microspheres were obtained. The surface of these silica microspheres was covered with a large number of hydroxyl groups, which showed good hydrophilicity.

[0020] (3) Preparation of antifog coating: 80 parts by weight of silicone modified acrylic resin, 15 parts by weight of epoxy resin E-51, 5 parts by weight of silica (SiO2) microspheres, 10 parts by weight of KH-560 silane coupling agent, 15 parts by weight of 4-vinylepoxycyclohexane, 5 parts by weight of 3,4-epoxycyclohexylmethyl 3,4-epoxycyclohexylcarboxylate reactive diluent, 3 parts by weight of chain extender diethylene glycol divinyl ether, 0.5 parts by weight of defoamer BYK350, 0.2 parts by weight of leveling agent EFKA 3777 and 3 parts by weight of photoinitiator diaryliodonium salt of phosphoric acid are cured into a film by a crawler curing machine.

[0021] 2. Performance Testing The pencil hardness of the coating was tested according to the national standard GBT-6739. According to GB / 9286-1998, adhesion is tested. Grade 0 indicates no peeling and the strongest adhesion. Grade 1 indicates slight peeling at the edges. Grade 2 indicates that the peeling is more severe than Grade 1. The water resistance of the membrane was determined according to GB / 1733-1993; the transmittance of the membrane was tested using ultraviolet light with a wavelength of 380 nm. The abrasion resistance of the membrane was tested according to GB / T 15036.2 standard; the membrane was scrubbed 200 times with acetone solution to observe its scrubbing resistance. Elongation at break: The elongation at break, determined by tensile testing, can, to some extent, indicate the toughness of the material. Coatings with higher elongation at break have better toughness. The performance is shown in Table 2 below. Table 2 project Water resistance No whitening after soaking for a week hardness 6H Light transmittance 93 wear-resistant WR3 Washable No change Adhesion / Grade 0 Elongation at break 24.24 Water contact angle 13.6° Oil contact angle 22.7° Comparative Example 1 (Comparative example without silica microspheres) A method for preparing an anti-fogging coating based on cationic curing includes the following steps: (1) Preparation of organosilicon-modified acrylic resin: By mass, 200 parts by mass of xylene were added to a three-necked flask equipped with a stirrer and a thermometer, and the temperature was raised to 120°C. 10 parts by mass of vinyldimethylethoxysilane, 15 parts by mass of vinyltriethoxysilane, 3 parts by mass of propyl acrylate, 5 parts by mass of butyl methacrylate, 9 parts by mass of hydroxyethyl methacrylate (HEMA), 5 parts by mass of hydroxypropyl acrylate (HPA), 5 parts by mass of tetrahydrofurfuryl acrylate, 50 parts by mass of glycidyl methacrylate, and 5 parts by mass of azobisisobutyronitrile were mixed evenly and then slowly added dropwise to the three-necked flask. The addition time was 3 h. After the addition was completed, the temperature was maintained for another 8 h. The organic solvent was recovered by vacuum distillation, and organosilicon-modified acrylic resin was obtained in the three-necked flask.

[0022] (2) Preparation of coating: The 80 parts by weight of silicone modified acrylic resin, 15 parts by weight of epoxy resin E-51, 10 parts by weight of KH-560 silane coupling agent, 15 parts by weight of 4-vinylepoxycyclohexane, 5 parts by weight of 3,4-epoxycyclohexylmethyl 3,4-epoxycyclohexylcarboxylate reactive diluent, 3 parts by weight of chain extender diethylene glycol divinyl ether, 0.5 parts by weight of defoamer BYK350, 0.2 parts by weight of leveling agent EFKA 3777 and 3 parts by weight of photoinitiator diaryliodonium salt of phosphoric acid were finally cured into a film by a crawler curing machine.

[0023] 2. Performance Testing The pencil hardness of the coating was tested according to the national standard GBT-6739. According to GB / 9286-1998, adhesion is tested. Grade 0 indicates no peeling and the strongest adhesion. Grade 1 indicates slight peeling at the edges. Grade 2 indicates that the peeling is more severe than Grade 1. The water resistance of the membrane was determined according to GB / 1733-1993; the transmittance of the membrane was tested using ultraviolet light with a wavelength of 380 nm. The abrasion resistance of the membrane was tested according to GB / T 15036.2 standard; the membrane was washed 200 times with acetone solution to observe its abrasion resistance. Elongation at break: The elongation at break, determined by tensile testing, can, to some extent, indicate the toughness of the material. Coatings with higher elongation at break have better toughness. The performance is shown in Table 3 below. Table 3 project Water resistance It turns white after soaking for three days hardness 5H Light transmittance 95 wear-resistant WR3 Washable No change Adhesion / Grade 0 Elongation at break 21.55 Water contact angle 78.5° Oil contact angle 98.4° Compared with Comparative Example 1, the performance test results of Examples 1 and 2 of the present invention show that the cationic curing antifog coating prepared by the present invention using specific raw materials has excellent mechanical properties (including hardness, wear resistance, etc.), solvent resistance, high adhesion, good light transmittance and hydrophilicity, reduces light scattering, focuses on maintaining transparency, has a low water-oil contact angle, and has very good antifog performance, achieving great technological progress.

[0024] The above description of the embodiments is only for the purpose of helping to understand the method and core ideas of the present invention. It should be noted that those skilled in the art can make various improvements and modifications to the present invention without departing from the principles of the invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

Claims

1. A method for preparing an anti-fogging coating based on cationic curing, characterized in that, Includes the following steps: (1) Preparation of organosilicon modified acrylic resin: Add organic solvent to a flask, heat up, mix organosilicon, alkyl acrylate or alkyl methacrylate, initiator and slowly add dropwise to a three-necked flask after uniform mixing. After the addition is completed, continue to keep warm, and recover the organic solvent by vacuum distillation to obtain organosilicon modified acrylic resin. (2) Preparation of silica microspheres: Add solvent and alkaline water to a three-necked flask, then add tetraethyl orthosilicate under stirring. Stir the mixture at room temperature, centrifuge the product with a high-speed centrifuge, wash the product with solvent, and dry it to obtain silica microspheres. (3) Preparation of antifog coating: The organosilicon modified acrylic resin obtained in step (1), the silica microspheres obtained in step (2), epoxy resin, reactive diluent, chain extender, defoamer, leveling agent and photoinitiator are cured into a film after being irradiated by ultraviolet lamp.

2. The method for preparing a cationic curing anti-fog coating according to claim 1, characterized in that, Includes the following steps: (1) Preparation of organosilicon modified acrylic resin: Add 100-400 parts by weight of organic solvent to a flask, heat to 90-110℃, add 15-30 parts by weight of organosilicon, 70-85 parts by weight of alkyl acrylate or alkyl methacrylate, 3-5 parts by weight of initiator, mix evenly and slowly drop into a three-necked flask, the dropping time is 1-4 h, after the dropping is completed, continue to keep warm for 1-10 h, and recover the organic solvent by vacuum distillation to obtain organosilicon modified acrylic resin; (2) Preparation of silica microspheres: 100-200 parts by weight of solvent and 15-50 parts by weight of alkaline water were added to a three-necked flask, and then 10-50 parts by weight of tetraethyl orthosilicate were added under stirring. The mixture was stirred at room temperature for 24-72 h. After the product was centrifuged by a high-speed centrifuge, the product was washed with solvent and dried to obtain silica microspheres. (3) Preparation of antifog coating: 60-90 parts by weight of silicone-modified acrylic resin obtained in step (1), 3-10 parts by weight of silica microspheres obtained in step (2), 10-30 parts by weight of epoxy resin, 5-30 parts by weight of reactive diluent, 3-10 parts by weight of chain extender, 0.5-2.5 parts by weight of defoamer, 0.2-1.5 parts by weight of leveling agent and 3-5 parts by weight of photoinitiator are cured into a film after being irradiated by ultraviolet lamp.

3. The method for preparing a cationic curing anti-fog coating according to claim 1, characterized in that, The solvent mentioned in step (1) is at least one or a mixture of several of the following: toluene, ethyl acetate, isooctyl acetate, butanone, chloroform, xylene, petroleum ether and DMF.

4. The method for preparing a cationic curing anti-fog coating according to claim 1, characterized in that, The organosiloxane mentioned in step (1) is at least one or a mixture of several of vinyltrimethoxysilane, vinyltri-β-methoxyethoxysilane, vinyldimethylethoxysilane, and vinyltriethoxysilane.

5. The method for preparing a cationic curing anti-fog coating according to claim 1, characterized in that, The alkyl acrylate or alkyl methacrylate mentioned in step (1) is: methyl methacrylate, methyl acrylate, propyl methacrylate, propyl acrylate, butyl methacrylate, butyl acrylate, isobutyl methacrylate, isobutyl acrylate, isoamyl methacrylate, isoamyl acrylate, hexyl methacrylate, hexyl acrylate, hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, hydroxypropyl methacrylate, tetrahydrofurfuryl acrylate, glycidyl methacrylate, diethylene glycol divinyl ether, 4-hydroxybutyl vinyl ether, or a mixture of at least one or more of these. The initiator is a mixture of at least one or more of the following: azo compounds, organic peroxides, and redox systems.

6. The method for preparing a cationic curing anti-fog coating according to claim 1, characterized in that, The solvent in step (2) is: at least one or a mixture of several of toluene, xylene, ethanol, and acetone; The alkaline water is a mixture of at least one or more of the following: ammonia water with a mass concentration of 5-20%, sodium carbonate solution with a mass concentration of 5-20%, sodium hydroxide solution with a mass concentration of 2-20%, triethylamine, and diethanolamine; the centrifuge requirements are: speed of 1000-2000 r / min, time of 10-20 min.

7. The method for preparing a cationic curing anti-fog coating according to claim 1, characterized in that, In step (3), the epoxy resin is a mixture of at least one or more of linear alicyclic and aromatic epoxy resins.

8. The method for preparing a cationic curing anti-fog coating according to claim 1, characterized in that, The active diluent in step (3) is at least one or a mixture of several of the following: KH-560 silane coupling agent, 4-vinylcyclohexane oxide, 3,4-epoxycyclohexylmethyl 3,4-epoxycyclohexyl carboxylate, 3-hydroxymethyl-3-ethyloxetane, 3-benzyloxymethyl-3-ethyloxetane, 3-ethyl-3-(phenoxymethyloxy)heptacyclic butane, 3-ethyl-3-(octoxymethyl)oxetane, and tetrahydroindene diepoxide; Chain extender: at least one or a mixture of several of diethylene glycol divinyl ether and triethylene glycol divinyl ether; The defoamer is a mixture of at least one or more of the following: organosilicon, organofluorine, and high molecular weight organosilicon; the leveling agent is a mixture of at least one or more of the following: acrylate and epoxy leveling agents.

9. The method for preparing a cationic curing anti-fog coating according to claim 1, characterized in that, In step (3), the cationic photoinitiator is at least one or a mixture of several of the following: triarylhexafluoroantimony thioonium salt, diaryliodoonium hexafluorophosphate, dialkylbenzoylmethyl thioonium salt, dialkyl-4-hydroxyphenyl thioonium salt, didodecylbenzeneiodoonium salt, diaryliodoonium phosphate, and triaryliodoonium phosphate.

10. A method for preparing an anti-fogging coating based on cationic curing, characterized in that, Includes the following steps: (1) Preparation of organosilicon modified acrylic resin: By mass, 200 parts by mass of xylene were added to a three-necked flask equipped with a stirrer and a thermometer, and the temperature was raised to 120°C. 10 parts by mass of vinyl dimethyl ethoxysilane, 15 parts by mass of vinyl triethoxysilane, 3 parts by mass of propyl acrylate, 5 parts by mass of butyl methacrylate, 9 parts by mass of hydroxyethyl methacrylate (HEMA), 5 parts by mass of hydroxypropyl acrylate (HPA), 5 parts by mass of tetrahydrofurfuryl acrylate, 50 parts by mass of glycidyl methacrylate, and 5 parts by mass of azobisisobutyronitrile were mixed evenly and then slowly added dropwise to the three-necked flask. The addition time was 3 h. After the addition was completed, the temperature was maintained for 8 h. The organic solvent was recovered by vacuum distillation. The organosilicon modified acrylic resin was obtained in the three-necked flask. (2) Preparation of silica microspheres: 100 parts by mass of toluene and 25 parts by mass of 10% ammonia solution were added to a three-necked flask equipped with a stirrer, and then 25 parts by mass of tetraethyl orthosilicate were added under stirring. The mixture was stirred at room temperature for 24 h, and the product was centrifuged at 1000 r / min for 20 min. The product was then washed three times with solvent and dried in an oven at 50 °C for 24 h to obtain silica microspheres. The surface of these silica microspheres is covered with a large number of hydroxyl groups, which gives them good hydrophilicity. (3) Preparation of antifog coating: 80 parts by weight of organosilicon modified acrylic resin obtained in step (1), 5 parts by weight of silica (SiO2) microspheres obtained in step (2), 15 parts by weight of epoxy resin E-51, 10 parts by weight of KH-560 silane coupling agent, 15 parts by weight of 4-vinylepoxycyclohexane, 5 parts by weight of 3,4-epoxycyclohexylmethyl 3,4-epoxycyclohexylcarboxylate reactive diluent, 3 parts by weight of chain extender diethylene glycol divinyl ether, 0.5 parts by weight of defoamer BYK350, 0.2 parts by weight of leveling agent EFKA 3777 and 3 parts by weight of photoinitiator diaryliodonium salt of phosphoric acid are finally cured into a film by a crawler curing machine.