Ultraviolet curing super-hydrophobic and oleophobic hardened coating and preparation method thereof

Abstract

The invention relates to the technical field of UV (ultraviolet) hardened coatings, in particular to an ultraviolet curing super-hydrophobic and oleophobic hardened coating and a preparation method thereof. The ultraviolet curing super-hydrophobic and oleophobic hardened coating is prepared from the following raw materials in parts by weight: 2-6 parts of bifunctional side chain fluorine-containing polyester type polyurethane modified acrylate, 10-40 parts of bifunctional polycarbonate type polyurethane modified acrylate and 15-30 parts of trifunctional polyether type polyurethane modified acrylate, the coating is prepared from the following components in parts by weight: 5-50 parts of hexa-functional polycarbonate type polyurethane modified acrylate, 100-180 parts of a UV reactive diluent, 6-12 parts of a photoinitiator, 0.5-3 parts of a flatting agent, 0.5-4 parts of a wetting agent, 0.5-3 parts of a defoaming agent and 0.5-8 parts of hydrophobic modified nano titanium oxynitride. The hardened coating prepared by the invention has the advantages of high adhesiveness, high hardness, high wear resistance, high yellowing property, high stain resistance and high durability.

Description

Technical Field

[0001] This invention relates to the field of UV curing coating technology, and in particular to a UV-curable superhydrophobic and oleophobic curing coating and its preparation method. Background Technology

[0002] PET film possesses excellent light transmittance, mechanical properties, heat resistance, and flexibility, making it widely used in automotive glass protection films, automotive headlight protection films, kitchenware panel protection films, and glass display screen protection films. However, pure PET film has poor hardness and scratch resistance, requiring a hardening coating to be applied to the surface of the PET base film to improve surface hardness and scratch resistance. Furthermore, the hardening coating must exhibit good adhesion stability to the PET film.

[0003] Existing hardened coatings mainly consist of photosensitive film-forming resins, UV-reactive diluents, photoinitiators, solvents, and leveling agents. The photosensitive film-forming resin is a multifunctional acrylic oligomer. Controlling the functional group degree of the acrylic oligomer controls the hardness and scratch resistance of the hardened coating. However, the high functional group degree of the photosensitive film-forming resin leads to its high viscosity, requiring a large amount of organic solvent for dilution and formulation to improve the processing and application performance of the hardened coating. The hardened coating is formed by the cross-linking reaction of the photosensitive film-forming resin and UV-reactive diluent under the action of ultraviolet light and a photoinitiator. When used as a protective film for automotive glass, higher requirements are placed on the scratch resistance and stain resistance of the hardened coating.

[0004] Existing stain-resistant hardening coatings reduce the surface energy of the hardened coating by adding small-molecule organosilicon or fluorinated antifouling additives, thereby improving its hydrophobic and oleophobic properties and stain resistance. This makes it difficult for oil films to adhere to the surface of the hardened coating, allowing windshield wipers to effectively remove the oil film from the automotive glass protective film and improve driving visibility. However, small-molecule organosilicon or fluorinated antifouling additives are incompatible with the hardened coating matrix, causing them to easily migrate to the surface of the hardened coating. As windshield wipers clean the automotive glass protective film, after a period of use, the small-molecule organosilicon or fluorinated antifouling additives on the surface of the hardened coating will migrate away from the hardened coating due to the periodic friction of the wiper blades, causing the protective film to lose its stain resistance and affecting its stain-resistant lifespan. Increasing the amount of small-molecule organosilicon or fluorinated antifouling additives to improve the stain resistance of the hardened coating will lead to a decrease in the adhesion between the hardened coating and the PET film, affecting the lifespan of the automotive glass protective film. Therefore, the inventors provide a UV-curable superhydrophobic and oleophobic hardening coating and its preparation method. Summary of the Invention

[0005] To address the technical problem of poor stain resistance and durability in existing hardened coatings, this invention provides an ultraviolet light-cured superhydrophobic and oleophobic hardened coating and its preparation method.

[0006] The ultraviolet light-curable superhydrophobic and oleophobic curing coating provided by this invention is achieved through the following technical solution: A UV-curable superhydrophobic and oleophobic hardening coating is made from the following raw materials in parts by weight: 2-6 parts of difunctional side-chain fluorinated polyester-type polyurethane modified acrylate, 10-40 parts of difunctional polycarbonate-type polyurethane modified acrylate, 15-30 parts of trifunctional polyether-type polyurethane modified acrylate, 5-50 parts of hexafunctional polycarbonate-type polyurethane modified acrylate, 100-180 parts of UV reactive diluent, 6-12 parts of photoinitiator, 0.5-3 parts of leveling agent, 0.5-4 parts of wetting agent, 0.5-3 parts of defoamer, and 0.5-8 parts of hydrophobic modified nano titanium oxynitride.

[0007] The hardened coating prepared by this invention has the advantages of high adhesion, high hardness, high wear resistance, and high stain resistance and durability. While ensuring the bonding performance between the hardened coating and the PET film, it endows the hardened coating with good wear resistance, scratch resistance, weather resistance, chemical corrosion resistance, stain resistance and stain resistance durability.

[0008] In this invention, by controlling the molecular weight of difunctional side-chain fluorinated polyester-type polyurethane-modified acrylate, difunctional polycarbonate-type polyurethane-modified acrylate, trifunctional polyether-type polyurethane-modified acrylate, and hexafunctional polycarbonate-type polyurethane-modified acrylate, and by combining them with UV-active diluents, the coating application requirements can be met without the use of additional organic solvents, and the smoothness of the hardened coating and the environmental friendliness of the production process can be improved.

[0009] Preferably, the difunctional side-chain fluorinated polyester polyurethane modified acrylate is made of aliphatic diisocyanate, side-chain fluorinated polyester diol, organotin catalyst, organic solvent, polymerization inhibitor, and end-capping agent; the molar ratio of the isocyanate group -NCO in the aliphatic diisocyanate to the molar ratio of the hydroxyl group -OH in the side-chain fluorinated polyester diol is (1.5-2):1.

[0010] The molecular weight of difunctional polyurethane-modified acrylates with fluorinated polyester side chains, difunctional polycarbonate-modified acrylates, trifunctional polyether-modified acrylates, and hexafunctional polycarbonate-modified acrylates is controlled by the -NCO / OH molar ratio. If the molecular weight is too high, the viscosity will be too high, requiring the addition of too much organic solvent for dilution and preparation. If the molecular weight is too low, the soft segment content will be too low, resulting in decreased flexibility. The hardened coating formed by cross-linking and curing will be brittle and prone to cracking under external impact, affecting the service life of automotive glass protective film.

[0011] Preferably, the aliphatic diisocyanate is at least one of isophorone diisocyanate (IPDI), dicyclohexylmethane diisocyanate (HMDI), norbornene diisocyanate (NBDI), and methylcyclohexyl diisocyanate (HTDI), which can ensure the hardness, wear resistance, scratch resistance, and yellowing resistance of the hardened coating.

[0012] Preferably, the capping agent is at least one of hydroxyethyl methacrylate, hydroxypropyl methacrylate, and hydroxybutyl methacrylate.

[0013] In the difunctional side-chain fluorinated polyester polyurethane modified acrylate, the end-capping agent is selected as hydroxy methacrylate, which has lower reactivity than hydroxy acrylate. This facilitates the migration of the linear difunctional side-chain fluorinated polyester polyurethane modified acrylate to the surface, and the fluorine element tends to accumulate on the surface of the hardened coating. After UV curing, a highly stain-resistant FPU surface structure is formed on the surface of the hardened coating, giving the hardened coating excellent weather resistance, chemical corrosion resistance, stain resistance, and stain resistance durability.

[0014] Preferably, the toluene, acetone, ethyl acetate, N,N-dimethylformamide, methyl ethyl ketone, and dimethyl carbonate are selected from at least one of these.

[0015] Preferably, the organotin catalyst is dibutyltin dilaurate and / or stannous octoate.

[0016] Preferably, the polymerization inhibitor is hydroquinone and / or p-hydroxyanisole.

[0017] Preferably, the side-chain fluorinated polyester diol is made from alicyclic diols, 1,4-cyclohexanedicarboxylic acid, fluorinated diols, and titanate catalysts, and the ratio of the total molar amount of hydroxyl groups in the fluorinated diols and alicyclic diols to the molar amount of carboxyl groups in the 1,4-cyclohexanedicarboxylic acid is (1.02-1.05):1.

[0018] Preferably, the alicyclic diol is at least one selected from 2-cyclohexylpropane-1,3-diol, 1,4-cyclohexanediol, and 1,2-cyclododecanediol.

[0019] Preferably, the fluorinated diol is at least one selected from hexafluoropentanediol, octafluoro-1,6-hexanediol, and 2,2,3,3,4,4-hexafluoro-1,5-pentanediol.

[0020] In the difunctional side-chain fluorinated polyester-modified acrylate, the fluorine element is distributed on the side chain of the PU main chain, which has little impact on the bonding strength between the hardened coating and the PET base film and can improve the mechanical strength of the hardened coating.

[0021] During film formation, the linear difunctional side-chain fluorinated polyester-modified acrylate, due to its significant polarity difference compared to other film-forming resins and reactive diluents, readily migrates to the surface of the hardened coating. After stepped heat treatment in the coating stage, the fluorine in the difunctional side-chain fluorinated polyester-modified acrylate tends to accumulate on the surface of the hardened coating. After UV curing, a highly stain-resistant FPU surface structure is formed on the hardened coating surface, endowing the hardened coating with excellent weather resistance, chemical corrosion resistance, stain resistance, and durability of stain resistance. The fluorine accumulated on the surface of the hardened coating can also effectively protect the PU main chain structure, overcoming the problem of poor hydrolytic stability caused by ester bonds in the difunctional side-chain fluorinated polyester-modified acrylate, and improving the hydrolytic stability and high-temperature resistance of the hardened coating.

[0022] Preferably, the difunctional polycarbonate-type polyurethane modified acrylate is made from aliphatic diisocyanate, polycarbonate diol, organotin catalyst, organic solvent, polymerization inhibitor, and end-capping agent; the molar ratio of the isocyanate group -NCO in the aliphatic diisocyanate to the molar ratio of the hydroxyl group -OH in the polycarbonate diol is (1.5-2):1; the polycarbonate diol is a polycarbonate diol with a molecular weight of 800-1500 using 1,4-cyclohexanediethanol as an initiator and / or a polycarbonate diol with a mixed initiator of 1,4-cyclohexanediethanol / 1,6-hexanediol; the aliphatic diisocyanate is at least one of isophorone diisocyanate IPDI, dicyclohexylmethane diisocyanate HMDI, norbornane diisocyanate NBDI, and methylcyclohexyl diisocyanate HTDI; and the end-capping agent is hydroxyethyl acrylate and / or hydroxypropyl acrylate.

[0023] In this invention, linear difunctional polycarbonate-type polyurethane modified acrylate plays a toughening role, transforming the resulting hardened coating from high-hardness and brittleness to high-hardness and high-toughness. The linear difunctional polycarbonate-type polyurethane modified acrylate ensures the hydrolytic stability, abrasion resistance, and weather resistance of the hardened coating. Furthermore, the introduction of the cyclohexane aliphatic ring structure further improves the hardness and abrasion resistance of the hardened coating while ensuring its resistance to yellowing.

[0024] Preferably, the trifunctional polyether-type polyurethane modified acrylate is composed of aliphatic triisocyanate, polyether glycol, organotin catalyst, organic solvent, polymerization inhibitor, and end-capping agent; the polyether glycol is polytetrahydrofuran ether glycol with a molecular weight of 600-1800 and / or branched polytetrahydrofuran ether glycol with a molecular weight of 800-2000; the aliphatic triisocyanate is HDI trimer and / or IPDI trimer; when the molar ratio of isocyanate group -NCO in the aliphatic triisocyanate to the molar ratio of hydroxyl group -OH in the polyether glycol is 1:(1.5-2), the end-capping agent is acrylic acid and / or methacrylic acid; when the molar ratio of isocyanate group -NCO in the aliphatic triisocyanate to the molar ratio of hydroxyl group -OH in the polyether glycol is (1.5-2):1, the end-capping agent is hydroxyethyl acrylate and / or hydroxypropyl acrylate.

[0025] In this invention, the trifunctional polyether-type polyurethane modified acrylate acts as a crosslinking agent and toughening agent. The soft segment-polytetrahydrofuran ether diol contained therein can improve the toughness of the formed dense three-dimensional network structure and has good hydrolytic stability, wear resistance, and low-temperature flexibility. Under the premise of ensuring the hardness and scratch resistance of the hardened coating, the overall hydrolytic stability, wear resistance, and low-temperature flexibility of the hardened coating can be further optimized.

[0026] Preferably, the hexafunctional polycarbonate-type polyurethane modified acrylate is made from aliphatic triisocyanate, polycarbonate diol, organotin catalyst, organic solvent, polymerization inhibitor, and end-capping agent; the molar ratio of the isocyanate group -NCO in the aliphatic triisocyanate to the molar ratio of the hydroxyl group -OH in the polycarbonate diol is (1.5-2):1; the polycarbonate diol includes at least one of polycarbonate diol with a molecular weight of 800-1500 as an initiator and polycarbonate diol with a mixed diol of 1,4-cyclohexanediol / 1,6-hexanediol as an initiator; the aliphatic triisocyanate is an HDI trimer and / or an IPDI trimer; and the end-capping agent is 1-(acryloyloxy)-3-(methacryloyloxy)-2-propanol.

[0027] In this invention, a hexafunctional polycarbonate-type polyurethane-modified acrylate is used as the main crosslinking agent. HDI trimer and / or IPDI trimer containing cyclohexyl groups are used as hard segments, and polycarbonate diol containing cyclohexyl groups, which exhibits excellent wear resistance and hydrolysis resistance, is used as a soft segment. Introducing cyclohexyl groups into the main chain structure compensates for the reduced hardness and wear resistance caused by the lack of phenyl groups, and also overcomes the yellowing problem caused by phenyl groups. This imparts excellent scratch resistance, wear resistance, hydrolysis resistance, weather resistance, and yellowing resistance to the hardened coating. Furthermore, as a soft segment, the ester bonds on the main chain of the polycarbonate diol have the same polarity as the ester bonds on the main chain of the PET base film, thereby ensuring excellent adhesion strength and stability between the hardened coating and the PET base film, which is beneficial for improving the stability and service life of the hardened coating.

[0028] Preferably, the photoinitiator is at least one of photoinitiator TPO, photoinitiator BP, photoinitiator 1173, photoinitiator 184, photoinitiator 2959, photoinitiator 819, and photoinitiator DETX.

[0029] Preferably, the UV reactive diluent includes a fluorinated UV reactive diluent, a monofunctional UV reactive diluent, and a polyfunctional UV reactive diluent, wherein the fluorinated UV reactive diluent is at least one of (perfluorocyclohexyl) methacrylate, hexafluorobutyl methacrylate, hexafluorobutyl acrylate, octafluoropentyl methacrylate, and dodecafluoroheptyl methacrylate.

[0030] Preferably, the mass ratio of the fluorinated UV reactive diluent to the difunctional side-chain fluorinated polyester polyurethane modified acrylate is (0.8-2):1; the total weight of the fluorinated UV reactive diluent and the difunctional side-chain fluorinated polyester polyurethane modified acrylate is 5-10 parts.

[0031] In this invention, the use of a fluorinated UV reactive diluent in combination with a difunctional side-chain fluorinated polyester-modified acrylate can effectively reduce the viscosity of superhydrophobic and oleophobic hardening coatings, meet the coating application requirements without the use of additional organic solvents, and improve the smoothness and environmental friendliness of the hardened coating.

[0032] Preferably, the monofunctional UV reactive diluent is at least one of butyl methacrylate, 2-ethylhexyl vinyl ether, tetrahydrofuran methyl methacrylate, isobornyl methacrylate, cyclohexyl methacrylate, 4-tert-butylcyclohexyl isobutylenoate, and 3-isobornylcyclohexyl acrylate.

[0033] Preferably, the multifunctional UV-reactive diluent is at least one of pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol hexaacrylate, trimethylolpropane triacrylate, hexanediol diacrylate, propoxylated neopentyl glycol diacrylate, and tripropylene glycol diacrylate.

[0034] In this invention, the UV reactive diluent is selected and optimized according to the type and amount of film-forming resin, which can ensure the application viscosity of the finished superhydrophobic and oleophobic hardening coating and improve the overall performance of the formed hardened coating.

[0035] The present invention provides a method for preparing a UV-curable superhydrophobic and oleophobic hardening coating, which is achieved through the following technical solution: A method for preparing a UV-curable superhydrophobic and oleophobic hardening coating includes the following steps: under light-shielding and nitrogen protection, accurately measured amounts of difunctional side-chain fluorinated polyester-type polyurethane-modified acrylate, difunctional polycarbonate-type polyurethane-modified acrylate, trifunctional polyether-type polyurethane-modified acrylate, hexafunctional polycarbonate-type polyurethane-modified acrylate, UV reactive diluent, leveling agent, wetting agent, defoamer, photoinitiator, and hydrophobic modified nano-titanium oxynitride are mixed evenly, filtered, discharged, and vacuum-packed to obtain the superhydrophobic and oleophobic hardening coating. Finally, the obtained superhydrophobic and oleophobic hardening coating is coated onto a base film, and after step-by-step heat treatment, it is UV-cured with a cumulative light irradiation energy of 350-450 mJ / cm². After UV curing, a superhydrophobic and oleophobic hardening coating is formed on the base film.

[0036] In summary, the present invention has the following advantages: 1. The superhydrophobic and oleophobic curing coating of the present invention is rapidly cured by ultraviolet light to form a hardened coating with advantages such as high adhesion, high hardness, high wear resistance, high stain resistance and durability, and high yellowing resistance, thereby enhancing the market competitiveness of automotive glass protective film.

[0037] 2. The preparation method of the superhydrophobic and oleophobic curable coating provided in this invention is simple to operate and generates no VOCs, thus giving it good environmental friendliness in production. The superhydrophobic and oleophobic curable coating can be rapidly cured under ultraviolet light to form a hardened coating, and no VOCs are generated during the curing process, thus giving it good environmental friendliness in processing. Detailed Implementation

[0038] To further understand the inventiveness and technical advancements of this invention, the preferred embodiments of this invention will be discussed in detail below with reference to examples and comparative examples.

[0039] Example: A UV-curable superhydrophobic and oleophobic hardening coating is formed by heat baking and UV curing of a superhydrophobic and oleophobic hardening coating. The hardening coating is made from the following raw materials in parts by weight: 2-6 parts of difunctional side-chain fluorinated polyester-type polyurethane modified acrylate, 10-40 parts of difunctional polycarbonate-type polyurethane modified acrylate, 15-30 parts of trifunctional polyether-type polyurethane modified acrylate, 5-50 parts of hexafunctional polycarbonate-type polyurethane modified acrylate, 100-180 parts of UV reactive diluent, 6-12 parts of photoinitiator, 0.5-3 parts of leveling agent, 0.5-4 parts of wetting agent, 0.5-3 parts of defoamer, and 0.5-8 parts of hydrophobic modified nano titanium oxynitride.

[0040] The photoinitiator is at least one selected from photoinitiator TPO, photoinitiator BP, photoinitiator 1173, photoinitiator 184, photoinitiator 2959, photoinitiator 819, and photoinitiator DETX. The hardened coating of this invention is used as a protective film for automotive windshields and requires excellent resistance to yellowing. Therefore, selecting any one or more combinations of photoinitiators 1173, 184, and 2959 as the photoinitiator system ensures the yellowing resistance of the hardened coating.

[0041] The leveling agent is at least one of the commercially available BYK-3500, BYK-3505, BYK-3510, BASF Rheovis HS 1332, Rheovis PU 1191, and Rheovis PU 1291.

[0042] The wetting agent is at least one of the commercially available BYK JET 9151, BYK 378, EBECREL 436, TEGO Dispers 689, BASF WE 3322, and Hydropalat WE 3650.

[0043] The defoamer is at least one of the commercially available BASF FoamStar SI 2293, FoamStar SI 2292, TEGO Airex 944, TEGO Airex 96, and BYK 1788 non-silicone defoamers.

[0044] The preparation method of hydrophobically modified nano-titanium oxynitride is as follows: 1. Nano-titanium oxynitride with an average particle size of 30 nm is first surface modified with epoxy silanes (such as γ-glycidoxypropyltrimethoxysilane and γ-glycidoxypropyltriethoxysilane) and mercaptosilanes (such as γ-mercaptopropyltrimethoxysilane and γ-mercaptopropyltriethoxysilane) to obtain nano-titanium oxynitride with surface grafted epoxy groups / mercapto groups; 2. The obtained nano-titanium oxynitride with surface-grafted epoxy / thiol groups is ultrasonically dispersed in an alcohol solvent to obtain a suspension. 1H,1H-perfluorohexylamine is prepared into a 0.25-2wt% 1H,1H-perfluorohexylamine alcohol solution with an alcohol solvent. Under magnetic stirring at 30-45℃, the 1H,1H-perfluorohexylamine alcohol solution is slowly added dropwise to the suspension to graft 1H,1H-perfluorohexylamine onto the surface of the nano-titanium oxynitride to form hydrophobic modified nano-titanium oxynitride.

[0045] In the hardened coating, the thiol groups on the surface of the hydrophobically modified nano-titanium oxynitride react with the active double bonds in the film-forming resin and UV-active diluent to form a thiol-thiol click chemical reaction, which stably loads the material onto the surface of the hardened coating to form a protective layer. This protective layer has properties such as stain resistance, antibacterial and mildew prevention, anti-glare, and anti-rainbow pattern.

[0046] The difunctional side-chain fluorinated polyester-type polyurethane modified acrylate comprises an aliphatic diisocyanate, a side-chain fluorinated polyester diol, an organotin catalyst, an organic solvent, a polymerization inhibitor, and a capping agent. The molar ratio of -NCO in the aliphatic diisocyanate to the molar ratio of -OH in the side-chain fluorinated polyester diol is (1.5-2):1. The side-chain fluorinated polyester diol comprises an alicyclic diol, 1,4-cyclohexanedicarboxylic acid, a fluorinated diol, and a titanate catalyst, produced through conventional polyester processes. The molar ratio of the total hydroxyl groups in the fluorinated diol and the alicyclic diol to the molar ratio of carboxyl groups in the 1,4-cyclohexanedicarboxylic acid is (1.02-1.05):1. The alicyclic diol is at least one selected from 2-cyclohexylpropane-1,3-diol, 1,4-cyclohexanediol, and 1,2-cyclododecanediol. The fluorinated diol is at least one of hexafluoropentanediol, octafluoro-1,6-hexanediol, and 2,2,3,3,4,4-hexafluoro-1,5-pentanediol.

[0047] Bifunctional polycarbonate-type polyurethane modified acrylates are composed of aliphatic diisocyanates, polycarbonate diols, organotin catalysts, organic solvents, polymerization inhibitors, and end-capping agents. The molar ratio of -NCO in the aliphatic diisocyanate to the molar ratio of -OH in the polycarbonate diol is (1.5-2):1. The end-capping agents are hydroxyethyl acrylate and / or hydroxypropyl acrylate, which have relatively high reactivity and can ensure the UV curing rate of the hardened coating. The polycarbonate diol is a polycarbonate diol with a molecular weight of 800-1500 using 1,4-cyclohexanediol as an initiator and / or a polycarbonate diol using a mixed diol of 1,4-cyclohexanediol / 1,6-hexanediol as an initiator, such as UM-CARB90 and UM-CARB100 from Ube Industries, Ltd. of Japan. Introducing aliphatic cyclohexyl groups into the polycarbonate diol can improve the hardness, abrasion resistance, scratch resistance, and yellowing resistance of the hardened coating.

[0048] Trifunctional polyether-type polyurethane modified acrylate is composed of aliphatic triisocyanate, polyether glycol, organotin catalyst, organic solvent, polymerization inhibitor, and end-capping agent. The aliphatic triisocyanate is an HDI trimer and / or IPDI trimer, ensuring the hardness, abrasion resistance, scratch resistance, and yellowing resistance of the hardened coating. The polyether glycol is a polytetrahydrofuran ether glycol with a molecular weight of 600-1800 and / or a branched polytetrahydrofuran ether glycol with a molecular weight of 800-2000. These polyether glycols possess good hydrolytic stability, abrasion resistance, and low-temperature flexibility, further optimizing the overall hydrolytic stability, abrasion resistance, and low-temperature flexibility of the hardened coating while ensuring its hardness and scratch resistance.

[0049] When the molar ratio of the isocyanate group -NCO in the aliphatic triisocyanate to the molar ratio of the hydroxyl group -OH in the polyether glycol is 1:(1.5-2), the end-capping agent is acrylic acid and / or methacrylic acid. The trifunctional polyether-type polyurethane modified acrylate prepared in this way has low viscosity and can impart excellent flexibility to the hardened coating.

[0050] When the molar ratio of the isocyanate group -NCO in the aliphatic triisocyanate to the molar ratio of the hydroxyl group -OH in the polyether diol is (1.5-2):1, the end-capping agent is hydroxyethyl acrylate and / or hydroxypropyl acrylate. The trifunctional polyether-type polyurethane modified acrylate prepared in this way has a low viscosity, which can impart good flexibility to the hardened coating and improve the wear resistance and scratch resistance of the hardened coating.

[0051] Hexafunctional polycarbonate-type polyurethane modified acrylate, as the main crosslinking film-forming agent, plays a strong role in the hardness, abrasion resistance, scratch resistance, salt spray resistance, and aging resistance of the formed hardened coating. Hexafunctional polycarbonate-type polyurethane modified acrylate is composed of aliphatic triisocyanate, polycarbonate diol, organotin catalyst, organic solvent, polymerization inhibitor, and end-capping agent. The aliphatic triisocyanate is an HDI trimer and / or IPDI trimer, ensuring the hardness, abrasion resistance, scratch resistance, and yellowing resistance of the hardened coating. The end-capping agent is 1-(acryloyloxy)-3-(methacryloyloxy)-2-propanol. The polycarbonate diol is preferably at least one of the following: polycarbonate diol with a molecular weight of 800-1500 using 1,4-cyclohexanediethanol as an initiator, or polycarbonate diol using a mixed diol of 1,4-cyclohexanediethanol / 1,6-hexanediol as an initiator, such as UM-CARB90 and UM-CARB100 from Ube Industries, Ltd. of Japan.

[0052] UV reactive diluents include fluorinated UV reactive diluents, monofunctional UV reactive diluents, and polyfunctional UV reactive diluents. The fluorinated UV reactive diluent is at least one of (perfluorocyclohexyl) methacrylate, hexafluorobutyl methacrylate, hexafluorobutyl acrylate, octafluoropentyl methacrylate, and dodecafluoroheptyl methacrylate. The mass ratio of the fluorinated UV reactive diluent to the difunctional side-chain fluorinated polyester-modified polyurethane acrylate is (0.8-2):1. Preferably, the total weight of the fluorinated UV reactive diluent and the difunctional side-chain fluorinated polyester-modified polyurethane acrylate is 5-10 parts.

[0053] The single-functional UV reactive diluent is at least one of butyl methacrylate, 2-ethylhexyl vinyl ether, tetrahydrofuran methyl methacrylate, isobornyl methacrylate, cyclohexyl methacrylate, 4-tert-butylcyclohexyl isobutylene acrylate, and 3-isobornylcyclohexyl acrylate.

[0054] The multifunctional UV reactive diluent is at least one of pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol hexaacrylate, trimethylolpropane triacrylate, hexanediol diacrylate, propoxylated neopentyl glycol diacrylate, and dipropylene glycol diacrylate.

[0055] The UV-active diluent for difunctional polycarbonate-type polyurethane modified acrylates is mainly composed of monofunctional acrylates with cyclohexyl groups (at least one of isoborneol methacrylate, cyclohexyl methacrylate, 4-tert-butylcyclohexyl isobutylene acrylate, and 3-isoborneolylcyclohexyl acrylate), which can effectively adjust the application viscosity of superhydrophobic and oleophobic hardening coatings.

[0056] The UV-active diluents in trifunctional polyether-type polyurethane modified acrylates are 2-ethylhexyl vinyl ether and / or tetrahydrofuran methyl methacrylate, which can effectively adjust the application viscosity of superhydrophobic and oleophobic hardening coatings.

[0057] The UV-active diluent for hexafunctional polycarbonate-type polyurethane-modified acrylates is mainly composed of monofunctional acrylates with cyclohexyl groups (at least one of isoborneol methacrylate, cyclohexyl methacrylate, 4-tert-butylcyclohexyl isobutylene acrylate, and 3-isoborneolylcyclohexyl acrylate), which can effectively adjust the application viscosity of superhydrophobic and oleophobic curing coatings. Furthermore, butyl methacrylate in the monofunctional UV-active diluent has a low viscosity. By selectively adding it to the semi-finished product after the superhydrophobic and oleophobic curing coating formulation process, the viscosity of the finished superhydrophobic and oleophobic curing coating can be adjusted to the optimal application viscosity, ensuring the smoothness and visual effect of the cured coating.

[0058] Multifunctional UV reactive diluents serve two purposes: firstly, they dilute and adjust the viscosity of the system; secondly, they participate in the cross-linking reaction, affecting the density of the formed three-dimensional network structure. When selecting multifunctional UV reactive diluents, the amounts of trifunctional polyether-type polyurethane-modified acrylate and hexagonal polycarbonate-type polyurethane-modified acrylate need to be considered. If the proportion of both is high, the viscosity of the film-forming resin in the system will be too high. In this case, a low-viscosity monofunctional UV reactive diluent should be used as the main active diluent, and an appropriate amount of multifunctional UV reactive diluent should be added to adjust, optimize, and improve the hardness, abrasion resistance, scratch resistance, weather resistance, and aging resistance of the hardened coating.

[0059] When the proportions of trifunctional polyether-type polyurethane modified acrylate and hexafunctional polycarbonate-type polyurethane modified acrylate are relatively low, a multifunctional UV reactive diluent can be used to enhance the crosslinking degree of the hardened coating, i.e., increasing the proportion of multifunctional UV reactive diluent in the UV reactive diluent. During formulation, after the multifunctional UV reactive diluent is uniformly mixed with the film-forming resin, functional additives, and hydrophobically modified nano-titanium oxynitride, a monofunctional UV reactive diluent is used to optimize the real-time viscosity of the mixture. This allows the viscosity of the hardened coating to be adjusted to the optimal application viscosity, ensuring the smoothness and visual effect of the hardened coating. In summary, the principle of UV reactive diluent formulation is to optimize the configuration based on the type and amount of film-forming resin to ensure the application viscosity of the finished superhydrophobic and oleophobic hardened coating and improve the overall performance of the formed hardened coating.

[0060] A method for preparing a UV-curable superhydrophobic and oleophobic hardening coating includes the following steps: Under light-shielding and nitrogen protection, accurately measured amounts of difunctional side-chain fluorinated polyester-type polyurethane-modified acrylate, difunctional polycarbonate-type polyurethane-modified acrylate, trifunctional polyether-type polyurethane-modified acrylate, hexafunctional polycarbonate-type polyurethane-modified acrylate, UV-active diluent, leveling agent, wetting agent, defoamer, photoinitiator, and hydrophobic modified nano-titanium oxynitride are mixed evenly, filtered, discharged, and vacuum-packed to obtain the superhydrophobic and oleophobic hardening coating. After the obtained superhydrophobic and oleophobic hardening coating is coated onto a base film, it is subjected to a stepped heat treatment followed by UV curing. The unit light irradiation energy is 40-60 mW / cm², the light exposure time is 5-10 s, and the cumulative light irradiation energy is 350-450 mJ / cm². After UV curing, a superhydrophobic and oleophobic hardening coating is formed on the base film.

[0061] Preparation Example 1: The preparation method of difunctional side-chain fluorinated polyester-type polyurethane modified acrylate is as follows: Step 1: The side-chain fluorinated polyester glycol is prepared using a conventional polyester glycol production method, specifically as follows: Under nitrogen protection, 1.55 mol (223.5 g) of 1,4-cyclohexanediethanol (CAS: 105-08-8, molecular weight: 144.21, Maclean), 2.0 mol (344.3 g) of 1,4-cyclohexanedicarboxylic acid (CAS: 1076-97-7, molecular weight: 172.17, Maclean), 0.5 mol (106.1 g) of 2,2,3,3,4,4-hexafluoro-1,5-pentanediol (CAS: 376-90-9, molecular weight: 212.09, Aladdin), and 2 g of antioxidant 1010 (CAS: 6683-19-8, Maclean) are added to a reaction vessel, and the temperature is raised to... The reaction was carried out at 135℃ for 3 hours, and then the temperature was increased to 230℃ at a constant rate over 4 hours and held for another 3 hours. The temperature at the top of the distillation column was controlled at 102±0.5℃. After 1 hour of reaction, the acid value of the reactants was measured. When the acid value was ≤30mgKOH / g, 0.28g of tetrabutyl titanate (CAS: 5593-70-4, Adamas / Titan) was added. Then, a vacuum treatment was carried out, and the pressure inside the reactor was gradually reduced from atmospheric pressure to 10Pa over 4 hours. The hydroxyl value of the reactants inside the reactor was measured. When the hydroxyl value of the reactants inside the reactor was lower than 114.0mgKOH / g, the vacuum was broken with nitrogen and the temperature was lowered to 110℃. After cooling to below 35℃, the product was unloaded and filled to obtain side-chain fluorinated polyester diol. The measured hydroxyl value of the side-chain fluorinated polyester diol was 112.1mgKOH / g. Step 2: Take 100g of the fluorinated polyester diol with side chains from Step 1 and place it in a reaction vessel. Heat to 125℃ and dehydrate under vacuum for 2 hours. Break the vacuum with nitrogen and adjust the temperature to 90℃. Add 52.48g of dicyclohexylmethane diisocyanate HMDI (CAS: 5124-30-1, molecular weight 262.34, West Asia Reagent), 0.01g of dibutyltin dilaurate, and 85g of acetone to the reaction vessel and mix thoroughly. Maintain the reaction at 90℃ for 2.5 hours. Take a sample to test the -NCO content of the reactants in the vessel (refer to GB / T12009.4-89 standard, i.e., -NCO reacts with di-n-butylamine to generate urea, and the -NCO content is measured by standardization with hydrochloric acid solution) until the theoretical value of the -NCO content in the system is reached, and the isocyanate-terminated polyurethane prepolymer is obtained. Step 3: Adjust the temperature of the isocyanate-terminated polyurethane prepolymer in the reactor to 70℃. Add 0.40g of hydroquinone (CAS: 123-31-9, Maclean) and 0.84g of tetrabutyl titanate to the reactor. Mix well and then add 26.10g of hydroxyethyl methacrylate (CAS: 868-77-9, molecular weight 130.14, Aladdin). Maintain the esterification and termination reaction at 70℃ for 90min. Take a sample to detect the -NCO content of the reactants in the reactor until the -NCO content of the reactants in the reactor is 0. Then remove acetone by vacuum distillation and cool to room temperature to obtain the difunctional side-chain fluorinated polyester polyurethane modified acrylate.

[0062] Preparation Example 2: The preparation method of difunctional polycarbonate-type polyurethane modified acrylate is as follows: Step 1: Under nitrogen protection, 90g of polycarbonate diol UM-CARB90 (Ube Industries, Inc., Japan; 1,4-cyclohexanediol CHDM / 1,6-hexanediol HDO=1 / 1, Mn=900, transparent viscous liquid) was placed in a reactor and heated to 125℃ for vacuum dehydration for 2 hours. The vacuum was then broken with nitrogen and the temperature was adjusted to 90℃. 44.46g of isophorone diisocyanate IPDI (CAS: 4098-71-9, molecular weight 222.283, Yantai Wanhua), 0.01g of dibutyltin dilaurate, and 78g of acetone were added to the reactor and mixed thoroughly. The reaction was maintained at 90℃ for 2.5 hours. The -NCO content of the reactants in the reactor was measured until the -NCO content in the reactants reached the theoretical value, thus obtaining isocyanate-terminated polyurethane prepolymer. Step 2: Adjust the temperature of the isocyanate-terminated polyurethane prepolymer in the reactor to 70℃. Add 0.48g of hydroquinone and 0.84g of tetrabutyl titanate to the reactor, mix well, and then add 23.04g of hydroxyethyl acrylate (CAS: 818-61-1, molecular weight 115.115, Aladdin). Maintain the temperature at 70℃ and perform the esterification and termination reaction for 90 minutes. Take a sample to detect the -NCO content of the reactants in the reactor until the -NCO content of the reactants in the reactor is 0. Then, remove acetone by vacuum distillation, cool to room temperature, and discharge to obtain the difunctional polycarbonate-type polyurethane modified acrylate.

[0063] Preparation Example 3-A: The preparation method of trifunctional polyether-type polyurethane modified acrylate is as follows: Step 1: Under nitrogen protection, 195g of polytetrahydrofuran ether diol PTG 650 (molecular weight 650, Shanxi Sanwei Group Co., Ltd., hydroxyl content 172.9mgKOH / g) was placed in a reactor and heated to 120℃ for vacuum dehydration for 2 hours. The vacuum was broken with nitrogen and the temperature was adjusted to 90℃. 95.28g of isophorone diisocyanate trimer (CAS: 67873-91-0, molecular weight 666.85, Bayer's grade Z 4470BA HDI trimer, curing amount 70±2%), 0.01g of dibutyltin dilaurate, and 145g of acetone were added to the reactor and mixed evenly. The temperature was raised to 90℃ and maintained at 90℃ for 2.5 hours. The -NCO content of the reactants in the reactor was measured until the -NCO content in the reactants in the reactor reached the theoretical value, thus obtaining a hydroxyl-terminated polyurethane prepolymer. Step 2: Adjust the temperature of the hydroxyl-terminated polyurethane prepolymer in the reactor to 70℃. Add 0.30g of hydroquinone and 0.96g of tetrabutyl titanate to the reactor and mix thoroughly. Mix 21.62g of acrylic acid (CAS: 79-10-7, molecular weight 72.06, Aladdin), 0.20g of hydroquinone, and 40g of acetone to prepare an AA dropping solution. Add the AA dropping solution to the reactor at a dropping rate of 2g / min. After the dropping is completed, maintain the temperature at 60℃ and continue the esterification reaction for 2 hours. Take a sample to detect the -NCO content of the reactants in the reactor until the -NCO content of the reactants in the reactor is 0. Then, remove the acetone by vacuum distillation and cool to room temperature to obtain trifunctional polyether-type polyurethane modified acrylate.

[0064] Preparation Example 3-B: The preparation method of trifunctional polyether-type polyurethane modified acrylate is as follows: Step 1: Under nitrogen protection, 195g of polytetrahydrofuran ether diol PTG 650 (molecular weight 650, Shanxi Sanwei Group Co., Ltd., measured hydroxyl content 172.9mgKOH / g) was placed in a reaction vessel. The mixture was heated to 120℃ and vacuum dehydrated for 2 hours. The vacuum was then broken with nitrogen and the temperature was adjusted to 90℃. 95.28g of isophorone diisocyanate trimer (CAS: 67873-91-0, molecular weight 666.85, Bayer AG, Germany, grade Z 4470BA) was added to the reaction vessel. HDI trimer (curing amount 70±2%), 0.01g dibutyltin dilaurate, and 145g acetone were mixed evenly and heated to 90℃. The reaction was maintained at 90℃ until the -NCO content in the system was 0. 66.70g isophorone diisocyanate IPDI was added, and the end-capping reaction was maintained at 90℃ for 2.5h. The -NCO content of the reactants in the reactor was measured until the -NCO content in the reactants in the reactor reached the theoretical value, thus obtaining the IPDI-terminated polyurethane prepolymer. Step 2: Adjust the temperature of the IPDI-terminated polyurethane prepolymer in the reactor to 70℃. Add 0.50g of hydroquinone and 0.96g of tetrabutyl titanate to the reactor, mix well, and then add 34.54g of hydroxyethyl acrylate (CAS: 818-61-1, molecular weight 115.115, Aladdin). Maintain the temperature at 70℃ and perform the esterification and termination reaction for 90min. Take a sample to detect the -NCO content of the reactants in the reactor until the -NCO content of the reactants in the reactor is 0. Then, remove acetone by vacuum distillation, cool to room temperature, and discharge to obtain trifunctional polyether-type polyurethane modified acrylate.

[0065] Preparation Example 4: The preparation method of hexafunctional polycarbonate-type polyurethane modified acrylate is as follows: Step 1: Under nitrogen protection, 270g of polycarbonate diol (Ube Industries, Inc., Japan, model UM-CARB90, 1,4-cyclohexanediol CHDM / 1,6-hexanediol HDO=1 / 1, average molecular weight Mn=900, transparent viscous liquid) was placed in a reaction vessel. The mixture was heated to 120℃ and dehydrated under vacuum for 2 hours. The vacuum was then broken with nitrogen, and the temperature was adjusted to 90℃. 95.28g of isophorone diisocyanate trimer (CAS: 67873-91-0, molecular weight 666.85, Bayer, Germany, grade Z 4470BA) was added to the reaction vessel. HDI trimer (curing amount 70±2%), 0.01g dibutyltin dilaurate, and 145g acetone were mixed evenly and heated to 90℃. The reaction was maintained at 90℃ until the -NCO content in the system was 0. 66.70g isophorone diisocyanate IPDI was added, and the reaction was maintained at 90℃ for 2.5h. The -NCO content of the reactants in the reactor was measured until the -NCO content in the reactants in the reactor reached the theoretical value, thus obtaining the IPDI-terminated polyurethane prepolymer. Step 2: Adjust the temperature of the IPDI-terminated polyurethane prepolymer in the reactor to 70℃. Add 0.54g of hydroquinone and 0.90g of tetrabutyl titanate to the reactor, mix well, and then add 64.28g of 1-(acryloyloxy)-3-(methacryloyloxy)-2-propanol (CAS: 1709-71-3, molecular weight: 214.215, Maclean). Maintain the temperature at 70℃ and perform the esterification and termination reaction for 90 minutes. Take a sample to detect the -NCO content of the reactants in the reactor until the -NCO content of the reactants in the reactor is 0. Then, remove acetone by vacuum distillation, cool to room temperature, and discharge to obtain hexafunctional polycarbonate-type polyurethane modified acrylate.

[0066] Preparation Example 5: The preparation method of hydrophobically modified nano-titanium oxynitride is as follows: Step 1: Add 90 parts by weight of ethanol and 10 parts by weight of deionized water to a beaker and mix thoroughly to obtain an ethanol-water solution. Add 0.2 parts by weight of γ-glycidoxypropyltrimethoxysilane KH560 (CAS: 2530-83-8, Aladdin) and 0.5 parts by weight of γ-mercaptopropyltrimethoxysilane (CAS: 4420-74-0, Aladdin) to the beaker and mix thoroughly. Then, add 0.1 mol / L dilute hydrochloric acid solution to adjust the pH to 3.0. Heat the mixture in a water bath to 50°C. Then, add 5 parts by weight of nano-titanium oxynitride (model CW-TiON-001, Shanghai Chaowei Nanotechnology Co., Ltd.) with an average particle size of 30 nm to the beaker and react for 2 hours under magnetic stirring at 120 rpm. Add 0.1 mol / L dilute sodium hydroxide solution to adjust the pH to 7.0. Then, vacuum dry to obtain nano-titanium oxynitride with surface grafted epoxy / mercapto groups. Step 2: Add 75 parts by weight of ethanol, 5 parts by weight of deionized water, and 20 parts by weight of acetone to a beaker and mix thoroughly to obtain an alcohol-ketone aqueous solution. Add 5 parts by weight of the nano-titanium oxynitride prepared in Step 1 with surface-grafted epoxy / thiol groups to the beaker and ultrasonically disperse for 15 min to obtain a suspension. Prepare a 1H,1H-perfluorohexanediol solution: Mix 0.2 parts by weight of 1H,1H-perfluorohexanediol (CAS: 355-34-0, molecular weight 299.085, Aladdin) with 40 parts by weight of ethanol and 10 parts by weight of acetone thoroughly. Maintain the suspension temperature at 40℃ in a water bath. Under magnetic stirring at 40℃ and 120 rpm, add the 1H,1H-perfluorohexanediol solution dropwise to the suspension at a rate of 1 g / min. After the addition is complete, continue the reaction for 1 hour under magnetic stirring at 40℃ and 120 rpm. After filtration and washing three times, vacuum dry to obtain the hydrophobic modified nano-titanium oxynitride product.

[0067] The difference between Preparation Example 6 and Preparation Example 2 is as follows: The preparation method of the difunctional polyether type polyurethane modified acrylate is as follows: Step 1, under nitrogen protection, 100g of polytetrahydrofuran ether diol PTG 1000 (molecular weight 1000, Shanxi Sanwei Group Co., Ltd., measured hydroxyl content 112.3mgKOH / g) is placed in a reaction vessel, heated to 125℃ and vacuum dehydrated for 2h, nitrogen is used to break the vacuum and the temperature is adjusted to 90℃, 44.46g of isophorone diisocyanate IPDI (CAS: 4098-71-9, molecular weight 222.283, Yantai Wanhua), 0.01g of dibutyltin dilaurate, and 85g of acetone are added to the reaction vessel and mixed evenly, heated to 90℃, and maintained at 90℃ for 2.5h. The -NCO content of the reactants in the vessel is measured until the -NCO content in the reactants in the vessel reaches the theoretical value, and the isocyanate-terminated polyurethane prepolymer is obtained; Step 3: Adjust the temperature of the isocyanate-terminated polyurethane prepolymer in the reactor to 70℃, add 0.45g of hydroquinone and 0.88g of tetrabutyl titanate to the reactor, mix well, and then add 23.04g of hydroxyethyl acrylate. Maintain the temperature at 70℃ and perform the esterification and termination reaction for 90 minutes. Take a sample to detect the -NCO content of the reactants in the reactor until the -NCO content of the reactants in the reactor is 0. Then, remove acetone by vacuum distillation, cool to room temperature and discharge to obtain the difunctional polyether type polyurethane modified acrylate.

[0068] The difference between Preparation Example 7 and Preparation Example 3-A is as follows: The preparation method of the trifunctional polyester-type polyurethane modified acrylate is as follows: Step 1, under nitrogen protection, 300g of polybutylene adipate diol JF-PE-3010T (molecular weight 1000, Zhejiang Huafeng New Material Co., Ltd., measured hydroxyl content 111.9mgKOH / g) was placed in a reaction vessel, heated to 120℃ and vacuum dehydrated for 2h, the vacuum was broken with nitrogen and the temperature was adjusted to 90℃, and 95.28g of isophorone diisocyanate trimer (CAS: 67873-91-0, molecular weight 666.85, Bayer, Germany grade Z 4470BA) was added to the reaction vessel. HDI trimer, cured amount 70±2%), 0.01g dibutyltin dilaurate, and 180g acetone were mixed evenly and reacted at 90℃ for 2.5h. The -NCO content of the reactants in the reactor was measured until the -NCO content in the reactor was 0, and hydroxyl-terminated polyurethane prepolymer was obtained. Step 2: Adjust the temperature of the hydroxyl-terminated polyurethane prepolymer in the reactor to 70℃. Add 0.40g of hydroquinone and 0.84g of tetrabutyl titanate to the reactor and mix evenly. Mix 21.62g of acrylic acid (CAS: 79-10-7, molecular weight 72.06, Aladdin), 0.20g of hydroquinone, and 40g of acetone evenly to prepare an AA dropping solution. Add the AA dropping solution to the reactor at a dropping rate of 2g / min. After the dropping is completed, maintain the temperature at 60℃ and continue the esterification reaction for 2 hours. Then, remove the acetone by vacuum distillation and cool to room temperature to obtain trifunctional polyester-type polyurethane modified acrylate.

[0069] The difference between Preparation Example 8 and Preparation Example 3-B is as follows: The preparation method of the trifunctional polyester-type polyurethane modified acrylate is as follows: Step 1, under nitrogen protection, 300g of polybutylene adipate diol JF-PE-3010T (molecular weight 1000, Zhejiang Huafeng New Material Co., Ltd., measured hydroxyl content 111.9mgKOH / g) is placed in a reaction vessel, heated to 120℃ and vacuum dehydrated for 2h, nitrogen is used to break the vacuum and the temperature is adjusted to 90℃, and 95.28g of isophorone diisocyanate trimer (CAS: 67873-91-0, molecular weight 666.85, Bayer, Germany grade Z 4470BA) is added to the reaction vessel. HDI trimer (curing amount 70±2%), 0.01g dibutyltin dilaurate, and 180g acetone were mixed evenly and reacted at 90℃ for 2.5h to obtain hydroxyl-terminated polyurethane prepolymer. Then, 66.70g isophorone diisocyanate IPDI was added, and the end-capping reaction was maintained at 90℃ for 1.5h. The -NCO content of the reactants in the reactor was measured until the -NCO content in the reactants in the reactor reached the theoretical value, thus obtaining the IPDI-terminated polyurethane prepolymer. Step 2: Adjust the temperature of the IPDI-terminated polyurethane prepolymer in the reactor to 70℃. Add 0.50g of hydroquinone and 0.96g of tetrabutyl titanate to the reactor, mix well, and then add 34.54g of hydroxyethyl acrylate (CAS: 818-61-1, molecular weight 115.115, Aladdin). Maintain the temperature at 70℃ and perform the esterification and termination reaction for 90min. Take a sample to detect the -NCO content of the reactants in the reactor until the -NCO content in the reactants in the reactor is 0. Then, remove acetone by vacuum distillation, cool to room temperature, and discharge to obtain trifunctional polyester-type polyurethane modified acrylate.

[0070] The difference between Preparation Example 9 and Preparation Example 4 is as follows: The preparation method of the hexafunctional polyether-type polyurethane modified acrylate is as follows: Step 1, under nitrogen protection, 195g of polytetrahydrofuran ether diol PTG 650 (molecular weight 650, Shanxi Sanwei Group Co., Ltd., measured hydroxyl content 172.9mgKOH / g) was placed in a reaction vessel, heated to 120℃ and vacuum dehydrated for 2h, nitrogen was used to break the vacuum and the temperature was adjusted to 90℃, and 95.28g of isophorone diisocyanate trimer (CAS: 67873-91-0, molecular weight 666.85, Bayer, Germany grade Z 4470BA) was added to the reaction vessel. HDI trimer (curing amount 70±2%), 0.01g dibutyltin dilaurate, and 145g acetone were mixed evenly and reacted at 90℃ for 2.5h to obtain hydroxyl-terminated polyurethane prepolymer. 66.70g isophorone diisocyanate IPDI was added and reacted at 90℃ for 1.5h. The -NCO content of the reactants in the reactor was measured until the -NCO content in the reactants in the reactor reached the theoretical value to obtain IPDI-terminated polyurethane prepolymer. Step 2: Adjust the temperature of the IPDI-terminated polyurethane prepolymer in the reactor to 70℃. Add 0.54g of hydroquinone and 0.90g of tetrabutyl titanate to the reactor, mix well, and then add 64.28g of 1-(acryloyloxy)-3-(methacryloyloxy)-2-propanol (CAS: 1709-71-3, molecular weight: 214.215, Maclean). Maintain the temperature at 70℃ and perform the esterification and termination reaction for 90 minutes. Take a sample to detect the -NCO content of the reactants in the reactor until the -NCO content in the reactants in the reactor is 0. Then, remove acetone by vacuum distillation, cool to room temperature, and discharge to obtain hexafunctional polyether-type polyurethane modified acrylate.

[0071] The difference between Preparation Example 10 and Preparation Example 5 is as follows: In step one of the preparation method of hydrophobically modified nano-titanium oxynitride, 90 parts by weight of ethanol and 10 parts by weight of deionized water are added to a beaker and mixed evenly to obtain an ethanol aqueous solution. 0.2 parts by weight of γ-glycidyl etheroxypropyltrimethoxysilane KH560 are added to the beaker, mixed evenly, and then 0.1 mol / L dilute hydrochloric acid aqueous solution is added dropwise to adjust the pH value to 3.0. The temperature is raised to 50°C in a water bath. Then, 5 parts by weight of nano-titanium oxynitride with an average particle size of 30 nm are added to the beaker, and the reaction is carried out for 2 h under magnetic stirring at 120 rpm. 0.1 mol / L dilute sodium hydroxide aqueous solution is added to adjust the pH value to 7. Then, the surface-grafted epoxy-based nano-titanium oxynitride is obtained by vacuum drying. The remaining steps are the same.

[0072] Example 1: A UV-curable superhydrophobic and oleophobic curable coating is formed by UV curing of a superhydrophobic and oleophobic curable coating. This curable coating is made from the following raw materials in parts by weight: 2 parts of the difunctional side-chain fluorinated polyester-type polyurethane-modified acrylate from Preparation Example 1, 3 parts of hexafluorobutyl acrylate (CAS: 54052-90-3, Aladdin), 15 parts of the difunctional polycarbonate-type polyurethane-modified acrylate from Preparation Example 2, 20 parts of 3-isoborneolylcyclohexyl acrylate (CAS: 903876-45-9, Shaanxi Didu Pharmaceutical Chemical Co., Ltd.), 20 parts of the trifunctional polyether-type polyurethane-modified acrylate from Preparation Example 3-B, 30 parts of tetrahydrofuran methacrylate (CAS: 2455-24-5, Shanghai Yi'en Chemical Technology Co., Ltd.), 30 parts of the hexafunctional polycarbonate-type polyurethane-modified acrylate from Preparation Example 4, and 45 parts of cyclohexyl methacrylate (CAS: 101-43-9 (Maclean), 15 parts trimethylolpropane triacrylate (CAS: 15625-89-5, Aladdin), 30 parts dipropylene glycol diacrylate (CAS: 42978-66-5, Aladdin), 10 parts butyl methacrylate (CAS: 97-88-1, Maclean), 9 parts photoinitiator 184 (CAS: 947-19-3, Aladdin), 3 parts leveling agent - BYK-3505, 3 parts wetting agent - TEGO Dispers689, 2 parts defoamer - Evonik BYK 1788 non-silicone defoamer, and 3 parts of the hydrophobic modified nano titanium oxynitride in Preparation Example 5.

[0073] A method for preparing a UV-curable superhydrophobic and oleophobic coating includes the following steps: Step 1: First, synthesize difunctional polyurethane-modified acrylates with fluorinated polyester side chains, difunctional polycarbonate-modified acrylates, trifunctional polyether-modified acrylates, and hexafunctional polycarbonate-modified acrylates. The preparation method for the difunctional polyurethane-modified acrylate with fluorinated polyester side chains is described in Preparation Example 1; the preparation method for the difunctional polycarbonate-modified acrylate is described in Preparation Example 2; the preparation method for the trifunctional polyether-modified acrylate is described in Preparation Example 3; and the preparation method for the hexafunctional polycarbonate-modified acrylate is described in Preparation Example 4. Step 2: Under light-protected and nitrogen-protected conditions, mix 2 parts of the difunctional side-chain fluorinated polyester-type polyurethane modified acrylate from Preparation Example 1, 3 parts of hexafluorobutyl acrylate, 15 parts of the difunctional polycarbonate-type polyurethane modified acrylate from Preparation Example 2, 20 parts of 3-isobornylcyclohexyl acrylate, 20 parts of the trifunctional polyether-type polyurethane modified acrylate from Preparation Example 3-B, 30 parts of tetrahydrofuran methacrylate, 30 parts of hexafunctional polycarbonate-type polyurethane modified acrylate from Preparation Example 4, 45 parts of cyclohexyl methacrylate, 15 parts of trimethylolpropane triacrylate, 30 parts of tripropylene glycol diacrylate, 9 parts of photoinitiator 184, 3 parts of BYK-3505, 3 parts of TEGO Dispers 689, and 2 parts of BYK 1788. Mix non-organosilicon defoamer and 3 parts of hydrophobic modified nano-titanium oxynitride from Preparation Example 5, add 10 parts of butyl methacrylate to adjust the viscosity of the system, mix well, filter, discharge, and vacuum package to obtain a superhydrophobic and oleophobic hardening coating. Step 3: The superhydrophobic and oleophobic curable coating is applied to a PET base film (TOYOBOA optical grade polyester film A4360, 125μm thick) using a coating equipment. It is then placed in an oven for stepped heat treatment, sequentially at 40℃ for 60s, 50℃ for 60s, and 65℃ for 120s. Following this, it is subjected to UV curing in a medium-pressure mercury lamp with a unit light energy of 50mW / cm², an exposure time of 8s, and a cumulative light energy of 500mJ / cm². After curing, the superhydrophobic and oleophobic curable coating forms an 8.0μm thick dry film on the PET base film. It is important to note that the unit light energy should be controlled within 50±5 mW / cm². While excessive unit light energy can improve curing and production efficiency, it can lead to higher internal stress in the resulting superhydrophobic and oleophobic curable coating, affecting its physicochemical properties.

[0074] The difference between Example 2 and Example 1 is that the UV-curable superhydrophobic and oleophobic curing coating is made from the following raw materials in parts by weight: 3 parts of the difunctional side-chain fluorinated polyester-type polyurethane modified acrylate from Preparation Example 1, 4.5 parts of hexafluorobutyl acrylate, 15 parts of the difunctional polycarbonate-type polyurethane modified acrylate from Preparation Example 2, 20 parts of 3-isobornylcyclohexyl acrylate, 20 parts of the trifunctional polyether-type polyurethane modified acrylate from Preparation Example 3-B, 30 parts of tetrahydrofuran methacrylate, 30 parts of hexafunctional polycarbonate-type polyurethane modified acrylate from Preparation Example 4, 45 parts of cyclohexyl methacrylate, 15 parts of trimethylolpropane triacrylate, 30 parts of tripropylene glycol diacrylate, 10 parts of butyl methacrylate, 9 parts of photoinitiator 184, 3 parts of BYK-3505, 3 parts of TEGO Dispers 689, and 2 parts of BYK 1788. Non-organic silicone defoamer, 3 parts of hydrophobic modified nano-titanium oxynitride in Preparation Example 5.

[0075] The difference between Example 3 and Example 1 is that the UV-curable superhydrophobic and oleophobic curing coating is made from the following raw materials in parts by weight: 4 parts of the difunctional side-chain fluorinated polyester polyurethane modified acrylate from Preparation Example 1, 6 parts of hexafluorobutyl acrylate, 15 parts of the difunctional polycarbonate polyurethane modified acrylate from Preparation Example 2, 20 parts of 3-isobornylcyclohexyl acrylate, 20 parts of the trifunctional polyether polyurethane modified acrylate from Preparation Example 3-B, 30 parts of tetrahydrofuran methacrylate, 30 parts of hexafunctional polycarbonate polyurethane modified acrylate from Preparation Example 4, 45 parts of cyclohexyl methacrylate, 15 parts of trimethylolpropane triacrylate, 30 parts of tripropylene glycol diacrylate, 10 parts of butyl methacrylate, 9 parts of photoinitiator 184, 3 parts of BYK-3505, 3 parts of TEGO Dispers 689, and 2 parts of BYK 1788. Non-organic silicone defoamer, 3 parts of hydrophobic modified nano-titanium oxynitride in Preparation Example 5.

[0076] The difference between Example 4 and Example 1 is that the UV-curable superhydrophobic and oleophobic curing coating is made from the following raw materials in parts by weight: 6 parts of the difunctional side-chain fluorinated polyester-type polyurethane modified acrylate from Preparation Example 1, 9 parts of hexafluorobutyl acrylate, 15 parts of the difunctional polycarbonate-type polyurethane modified acrylate from Preparation Example 2, 20 parts of 3-isobornylcyclohexyl acrylate, 20 parts of the trifunctional polyether-type polyurethane modified acrylate from Preparation Example 3-B, 30 parts of tetrahydrofuran methacrylate, 30 parts of the hexafunctional polycarbonate-type polyurethane modified acrylate from Preparation Example 4, 45 parts of cyclohexyl methacrylate, 15 parts of trimethylolpropane triacrylate, 30 parts of tripropylene glycol diacrylate, 10 parts of butyl methacrylate, 9 parts of photoinitiator 184, 3 parts of BYK-3505, 3 parts of TEGO Dispers 689, and 2 parts of BYK 1788. Non-organic silicone defoamer, 3 parts of hydrophobic modified nano-titanium oxynitride in Preparation Example 5.

[0077] The difference between Example 5 and Example 1 is that the UV-curable superhydrophobic and oleophobic curing coating is made from the following raw materials in parts by weight: 3 parts of the difunctional side-chain fluorinated polyester polyurethane modified acrylate from Preparation Example 1, 4.5 parts of hexafluorobutyl acrylate, 15 parts of the difunctional polycarbonate polyurethane modified acrylate from Preparation Example 2, 20 parts of 3-isobornylcyclohexyl acrylate, 20 parts of the trifunctional polyether polyurethane modified acrylate from Preparation Example 3-A, 30 parts of tetrahydrofuran methacrylate, 30 parts of hexafunctional polycarbonate polyurethane modified acrylate from Preparation Example 4, 45 parts of cyclohexyl methacrylate, 15 parts of trimethylolpropane triacrylate, 30 parts of tripropylene glycol diacrylate, 10 parts of butyl methacrylate, 9 parts of photoinitiator 184, 3 parts of BYK-3505, 3 parts of TEGO Dispers 689, and 2 parts of BYK 1788. Non-organic silicone defoamer, 3 parts of hydrophobic modified nano-titanium oxynitride in Preparation Example 5.

[0078] The difference between Example 6 and Example 1 is that the UV-curable superhydrophobic and oleophobic curing coating is made from the following raw materials in parts by weight: 2 parts of the difunctional side-chain fluorinated polyester polyurethane modified acrylate from Preparation Example 1, 2 parts of hexafluorobutyl acrylate, 2.6 parts of (perfluorocyclohexyl) methacrylate (CAS: 40677-94-9, Ron), 25 parts of the difunctional polycarbonate polyurethane modified acrylate from Preparation Example 2, 30 parts of 3-isobornylcyclohexyl acrylate, 15 parts of the trifunctional polyether polyurethane modified acrylate from Preparation Example 3-B, 20 parts of tetrahydrofuran methacrylate, 20 parts of the hexafunctional polycarbonate polyurethane modified acrylate from Preparation Example 4, 40 parts of cyclohexyl methacrylate, 35 parts of trimethylolpropane triacrylate, 20 parts of tripropylene glycol diacrylate, 9 parts of photoinitiator 184, 4 parts of butyl methacrylate, 3 parts of BYK-3505, and 3 parts of TEGODispers. 689, 2 parts of BYK 1788 non-organosilicone defoamer, and 3 parts of the hydrophobic modified nano-titanium oxynitride in Preparation Example 5.

[0079] The difference between Example 7 and Example 1 is that the UV-curable superhydrophobic and oleophobic curing coating is made from the following raw materials in parts by weight: 3 parts of the difunctional side-chain fluorinated polyester polyurethane modified acrylate of Preparation Example 1, 6 parts of octafluoropentyl methacrylate (CAS: 355-93-1, Maclean), 35 parts of the difunctional polycarbonate polyurethane modified acrylate of Preparation Example 2, 50 parts of 3-isobornylcyclohexyl acrylate, 30 parts of the trifunctional polyether polyurethane modified acrylate of Preparation Example 3-B, 45 parts of tetrahydrofuran methacrylate, 40 parts of the hexafunctional polycarbonate polyurethane modified acrylate of Preparation Example 4, 60 parts of cyclohexyl methacrylate, 15 parts of trimethylolpropane triacrylate, 30 parts of tripropylene glycol diacrylate, 16 parts of butyl methacrylate, 10 parts of photoinitiator 184, 3 parts of BYK-3505, 3 parts of TEGO Dispers 689, and 2 parts of BYK. 1788 non-organosilicon defoamer, 3 parts of hydrophobic modified nano-titanium oxynitride in Preparation Example 5.

[0080] The difference between Example 8 and Example 1 is that the UV-curable superhydrophobic and oleophobic curing coating is made from the following raw materials in parts by weight: 2.6 parts of the difunctional side-chain fluorinated polyester polyurethane modified acrylate of Preparation Example 1, 5.2 parts of dodecafluoroheptyl methacrylate (CAS: 2261-99-6, Aladdin), 10 parts of the difunctional polycarbonate polyurethane modified acrylate of Preparation Example 2, 20 parts of 3-isobornylcyclohexyl acrylate, 15 parts of the trifunctional polyether polyurethane modified acrylate of Preparation Example 3-B, 30 parts of tetrahydrofuran methacrylate, 45 parts of the hexafunctional polycarbonate polyurethane modified acrylate of Preparation Example 4, 70 parts of cyclohexyl methacrylate, 20 parts of trimethylolpropane triacrylate, 25 parts of tripropylene glycol diacrylate, 12 parts of butyl methacrylate, 9.5 parts of photoinitiator 184, 3 parts of BYK-3505, 3 parts of TEGO Dispers 689, and 2 parts of BYK. 1788 Non-organic silicone defoamer, 3 parts of the hydrophobic modified nano-titanium oxynitride in Preparation Example 5.

[0081] The difference between Comparative Example 1 and Example 1 is that the UV-curable superhydrophobic and oleophobic curing coating is made from the following raw materials in parts by weight: 5 parts hexafluorobutyl acrylate, 15 parts difunctional polycarbonate-type polyurethane modified acrylate from Preparation Example 2, 20 parts 3-isobornylcyclohexyl acrylate, 20 parts trifunctional polyether-type polyurethane modified acrylate from Preparation Example 3, 30 parts tetrahydrofuran methacrylate, 30 parts hexafunctional polycarbonate-type polyurethane modified acrylate from Preparation Example 4, 45 parts cyclohexyl methacrylate, 15 parts trimethylolpropane triacrylate, 30 parts tripropylene glycol diacrylate, 10 parts butyl methacrylate, 9 parts photoinitiator 184, 3 parts leveling agent - BYK-331, 3 parts wetting agent - TEGO Dispers 689, 2 parts defoamer - Evonik BYK 1788 non-silicone defoamer, and 3 parts hydrophobic modified nano titanium oxynitride from Preparation Example 5.

[0082] The difference between Comparative Example 2 and Example 1 is that the UV-curable superhydrophobic and oleophobic curing coating is made from the following raw materials in parts by weight: 1 part of the difunctional side-chain fluorinated polyester polyurethane modified acrylate of Preparation Example 1, 1.5 parts of hexafluorobutyl acrylate, 15 parts of the difunctional polycarbonate polyurethane modified acrylate of Preparation Example 2, 20 parts of 3-isobornylcyclohexyl acrylate, 20 parts of the trifunctional polyether polyurethane modified acrylate of Preparation Example 3, 30 parts of tetrahydrofuran methacrylate, 30 parts of the hexafunctional polycarbonate polyurethane modified acrylate of Preparation Example 4, 45 parts of cyclohexyl methacrylate, 15 parts of trimethylolpropane triacrylate, 30 parts of tripropylene glycol diacrylate, 10 parts of butyl methacrylate, 9 parts of photoinitiator 184, 3 parts of BYK-3505, 3 parts of TEGO Dispers 689, and 2 parts of BYK 1788. Non-organic silicone defoamer, 3 parts of hydrophobic modified nano-titanium oxynitride in Preparation Example 5.

[0083] The difference between Comparative Example 3 and Example 1 is that the UV-curable superhydrophobic and oleophobic curing coating was made from the following raw materials in parts by weight: 8 parts of the difunctional side-chain fluorinated polyester-type polyurethane modified acrylate from Preparation Example 1, 12 parts of hexafluorobutyl acrylate, 15 parts of the difunctional polycarbonate-type polyurethane modified acrylate from Preparation Example 2, 20 parts of 3-isobornylcyclohexyl acrylate, 20 parts of the trifunctional polyether-type polyurethane modified acrylate from Preparation Example 3, 30 parts of tetrahydrofuran methacrylate, 30 parts of the hexafunctional polycarbonate-type polyurethane modified acrylate from Preparation Example 4, 45 parts of cyclohexyl methacrylate, 15 parts of trimethylolpropane triacrylate, 30 parts of tripropylene glycol diacrylate, 10 parts of butyl methacrylate, 9 parts of photoinitiator 184, 3 parts of BYK-3505, 3 parts of TEGO Dispers 689, and 2 parts of BYK 1788. Non-organic silicone defoamer, 3 parts of hydrophobic modified nano-titanium oxynitride from Preparation Example 5, and 50 parts of organic solvent - ethyl acetate.

[0084] The coating process of the superhydrophobic and oleophobic curable coating is as follows: The superhydrophobic and oleophobic curable coating is applied to a PET base film (TOYOBOA optical grade polyester film A4360, thickness 125μm) using a coating equipment. Then, it is put into an oven for stepped heat treatment, which is carried out sequentially at 70℃ for 30s, 80℃ for 60s, and 85℃ for 150s. After removing the organic solvent - ethyl acetate, it is put into a medium-pressure mercury lamp for ultraviolet curing treatment. The unit light energy is 50mW / cm², the exposure time is 8s, and the cumulative light energy is 500mJ / cm². After curing, a superhydrophobic and oleophobic curable coating with a dry film thickness of 8.0μm is formed on the PET base film.

[0085] The difference between Comparative Example 4 and Example 1 is that 15 parts of the difunctional polycarbonate-type polyurethane modified acrylate in Preparation Example 2 were replaced with 15 parts of the difunctional polyether-type polyurethane modified acrylate in Preparation Example 6, while the other components remained unchanged.

[0086] The difference between Comparative Example 5 and Example 5 is that 20 parts of the trifunctional polyether polyurethane modified acrylate in Preparation Example 3-A in the UV-curable superhydrophobic and oleophobic hardening coating formulation were replaced with 20 parts of the trifunctional polyester polyurethane modified acrylate in Preparation Example 7, while the other components remained unchanged.

[0087] The difference between Comparative Example 6 and Example 1 is that 20 parts of the trifunctional polyether polyurethane modified acrylate in Preparation Example 3-B of the UV-curable superhydrophobic and oleophobic curing coating formulation were replaced with 20 parts of the trifunctional polyester polyurethane modified acrylate in Preparation Example 8, while the other components remained unchanged.

[0088] The difference between Comparative Example 7 and Example 1 is that 30 parts of the hexafunctional polycarbonate-type polyurethane modified acrylate in Preparation Example 4 were replaced with 30 parts of the hexafunctional polyether-type polyurethane modified acrylate in Preparation Example 9, while the other components remained unchanged.

[0089] The difference between Comparative Example 8 and Example 1 is that the 30 parts of hexafunctional polycarbonate-type polyurethane modified acrylate in the UV-curable superhydrophobic and oleophobic curing coating formulation of Example 4 were replaced with 30 parts of commercially available hexafunctional polyurethane modified acrylate (AgiSyn 716 hexafunctional aliphatic modified polyester acrylate from Shandong Shoucheng Chemical Co., Ltd.), while the other components remained unchanged.

[0090] The difference between Comparative Example 9 and Example 1 is that no hydrophobic modified nano-titanium oxynitride is added to the UV-cured superhydrophobic and oleophobic hardening coating. Specifically, the UV-curable superhydrophobic and oleophobic curing coating is made from the following raw materials in parts by weight: 3 parts of the difunctional side-chain fluorinated polyester-type polyurethane modified acrylate of Preparation Example 1, 4.5 parts of hexafluorobutyl acrylate, 15 parts of the difunctional polycarbonate-type polyurethane modified acrylate of Preparation Example 2, 20 parts of 3-isobornylcyclohexyl acrylate, 20 parts of the trifunctional polyether-type polyurethane modified acrylate of Preparation Example 3-B, 30 parts of tetrahydrofuran methacrylate, 30 parts of hexafunctional polycarbonate-type polyurethane modified acrylate of Preparation Example 4, 45 parts of cyclohexyl methacrylate, 15 parts of trimethylolpropane triacrylate, 30 parts of tripropylene glycol diacrylate, 10 parts of butyl methacrylate, 9 parts of photoinitiator 184, 3 parts of BYK-3505, 3 parts of TEGO Dispers 689, and 2 parts of BYK 1788 non-silicone defoamer.

[0091] The difference between Comparative Example 10 and Example 1 is that 3 parts of the hydrophobic modified nano titanium oxynitride in Preparation Example 5 were replaced with 3 parts of the hydrophobic modified nano titanium oxynitride in Preparation Example 10, while the other components remained unchanged.

[0092] Control group: The existing superhydrophobic and oleophobic curable coating formulation is as follows: 5 parts octafluoroamyl methacrylate, 20 parts bifunctional polyurethane acrylate SD 0442 from Guangzhou Songda New Material Technology Co., Ltd., 30 parts hexafunctional aromatic polyurethane acrylate SD 7549 from Guangzhou Songda New Material Technology Co., Ltd., 30 parts tetrahydrofuran methyl methacrylate, 45 parts cyclohexyl methacrylate, 30 parts tripropylene glycol diacrylate, and 150 parts organic solvent - ethyl acetate.

[0093] Under light-protected and nitrogen-protected conditions, 5 parts of octafluoroamyl methacrylate, 20 parts of bifunctional polyurethane acrylate SD 0442 from Guangzhou Songda New Material Technology Co., Ltd., 30 parts of hexafunctional aromatic polyurethane acrylate SD 7549 from Guangzhou Songda New Material Technology Co., Ltd., 30 parts of tetrahydrofuran methyl methacrylate, 45 parts of cyclohexyl methacrylate, 30 parts of tripropylene glycol diacrylate, and 150 parts of organic solvent-ethyl acetate are mixed, filtered, discharged, and vacuum-packed to obtain a superhydrophobic and oleophobic curable coating.

[0094] The coating process for the superhydrophobic and oleophobic curable coating is as follows: The existing superhydrophobic and oleophobic curable coating is applied to a PET base film (TOYOBOA optical grade polyester film A4360, thickness 125μm) using a coating equipment. Then, it is placed in an oven for stepped heat treatment, successively subjected to heat treatment at 70℃ for 30s, at 80℃ for 60s, and at 85℃ for 150s. After removing the organic solvent - ethyl acetate, it is placed in a medium-pressure mercury lamp for ultraviolet curing treatment. The unit light energy is 50mW / cm², the exposure time is 8s, and the cumulative light energy is 500mJ / cm². After curing, a superhydrophobic and oleophobic curable coating with a dry film thickness of 8.0μm is formed on the PET base film.

[0095] Table 1: Test parameters of the hardened coating / PET composite film in Examples 1-8, control group, and Comparative Examples 1-10

[0096] Notes: 1. The contact angle of the coating was tested using a TY-SDJ02 contact angle meter with a droplet volume of 2.5 μL. Three tests were performed, and the average value was taken. 2. The specific test method for the contact angle after 1000 rubs: A dedicated eraser ER-502 was used, with a load of 10 N, a test speed of 40 times / min, and a rubbing stroke of 20 mm. The hardened coating / PET composite film was placed on the test platform, and the eraser was used to repeatedly rub the film under the above conditions. After 1000 rubs, the droplet angle of the hardened coating was measured using a contact angle meter. 3. Hardness was determined according to GB / T6739-2022 "Determination of Hardness of Paints and Varnishes by Pencil Method". 4. Transmittance and haze were measured using a YH1100 transmittance and haze meter (measurement range 400~700 nm) from Guangdong Yuelian Instrument Co., Ltd.

[0097] Based on Example 1 and the control group, and in conjunction with Table 1, it can be seen that the superhydrophobic and oleophobic curing coating of the present invention does not require the addition of organic solvents and still meets the low viscosity requirements of the coating process. The prepared superhydrophobic and oleophobic curing coating has better hydrophobic and oleophobic properties and higher light transmittance than the curing coating formed in the control group.

[0098] Based on Example 1 and Comparative Example 1, and referring to Table 1, it can be seen that the initial contact angle and the contact angle after 1000 rubs with an eraser in Comparative Example 1, which uses hexafluorobutyl acrylate as the main stain-resistant additive, are worse than those in Example 1, which uses a compound of difunctional side-chain fluorinated polyester polyurethane modified acrylate and hexafluorobutyl acrylate. In particular, the contact angle after 1000 rubs with an eraser changes by -4.7° in Comparative Example 1, while it only changes by -2.3° in Example 1. Therefore, it can be concluded that using a compound of difunctional side-chain fluorinated polyester polyurethane modified acrylate and hexafluorobutyl acrylate as a stain-resistant additive can improve the hydrophobic and oleophobic properties, abrasion resistance, and scratch resistance of the hardened coating.

[0099] Table 2: Test parameters of hardened coatings in Examples 1-8, control group, and comparative examples 1-10

[0100] Notes: 5. The adhesion of the hardened coating was determined according to ASTM D3359-09, with a dry film thickness of 8.0 μm. 6. The steel wool abrasion resistance test was conducted using an ASR-339A abrasion testing machine. The friction medium was #0000 steel wool, and the load was 1000g. The steel wool was repeatedly rubbed under the above conditions. After 100 rubs, the surface of the hardened coating was observed for scratches until scratches appeared. If no scratches were observed after 4000 rubs, but scratches appeared after 4100 rubs, then the steel wool abrasion resistance was considered to be no scratches after 4000 rubs. 7. Neutral Salt Spray Resistance Test: According to GB / T 1771-2007 "Determination of Neutral Salt Spray Resistance of Paints and Varnishes", the test conditions are: temperature: 35±2°C; sodium chloride solution concentration: 5%; pH value: 6.5-7.2, test time: 72.0h. After the neutral salt spray test, the hardened coating is marked with a cross-cut pattern using a cross-cut tool according to ASTM D3359-09 standard. 3M 600 tape is then applied to the marked cross-cut pattern and quickly peeled off at a 180-degree angle. The cross-cut pattern removal is observed using a magnifying glass. 8. **Double 85 Aging Test:** After aging the hardened coating in an 85℃, 85%RH constant temperature and humidity chamber for 1000 hours, remove it and allow it to cool to room temperature for 2 hours. Following ASTM D3359-09 standards, use a cross-cut tester to draw a grid on the coating surface. Apply 3M 600 tape to the grid lines and then quickly peel it off at a 180-degree angle. Observe the removal of the grid lines using a magnifying glass. 9. **Yellowing Resistance:** After aging the hardened coating in an 85℃, 85%RH constant temperature and humidity chamber for 1000 hours, remove it and allow it to cool to room temperature for 2 hours. Measure the ΔE value of the hardened coating using a BYK 6801 spectrophotometer. A smaller ΔE value indicates better yellowing resistance of the hardened coating.

[0101] Based on Example 1 and the control group, and referring to Tables 1-2, it can be seen that the superhydrophobic and oleophobic hardened coating prepared in this invention has better hydrophobic and oleophobic properties and anti-yellowing properties than the hardened coating formed in the control group. Although the hexafunctional aromatic polyurethane acrylate SD 7549 in the control group can ensure that the hardened coating has good wear resistance, it will lead to a decrease in the weather resistance and anti-yellowing properties of the hardened coating.

[0102] Based on Example 1 and Comparative Example 1, and in conjunction with Tables 1-2, it can be seen that the hardened coating prepared by the compound of difunctional side-chain fluorinated polyester polyurethane modified acrylate and hexafluorobutyl acrylate in Example 1 showed no scratches and a color difference ΔE=0.89 after 4000 rubs, while the hardened coating in Comparative Example 1 showed no scratches and a color difference ΔE=1.36 after 3700 rubs. Using the compound of difunctional side-chain fluorinated polyester polyurethane modified acrylate and hexafluorobutyl acrylate as a stain-resistant additive can improve the wear resistance and anti-yellowing properties of the hardened coating.

[0103] Based on Examples 1-4 and Comparative Examples 2-3, and referring to Table 1-2, it can be seen that the hydrophobic and oleophobic properties of the hardened coating increase with the increase of the content of difunctional side-chain fluorinated polyester polyurethane modified acrylate and hexafluorobutyl acrylate. The total addition amount of difunctional side-chain fluorinated polyester polyurethane modified acrylate and hexafluorobutyl acrylate should be controlled at 5-15 parts to ensure the hydrophobic and oleophobic properties, abrasion resistance, and scratch resistance of the hardened coating. Excessive addition, while beneficial to hydrophobicity, oleophobicity, abrasion resistance, and scratch resistance, will affect adhesion and the bonding stability between the hardened coating and the base film, thus affecting the service life of the hardened coating / PET composite film. Conversely, too low an addition amount will not significantly improve hydrophobicity and oleophobicity, and will not provide optimal stain resistance and stain durability.

[0104] Based on Example 1 and Comparative Example 4, and referring to Tables 1-2, it can be seen that replacing the difunctional polycarbonate-type polyurethane modified acrylate with a difunctional polyether-type polyurethane modified acrylate has a positive effect on the flexibility and light transmittance of the hardened coating, but it will adversely affect the wear resistance and scratch resistance of the hardened coating. In the contact angle after 1000 cycles of rubber rubbing, the change rate of Comparative Example 4 is -3.6°, while that of Example 1 is only -2.3°. In the steel wool rubbing test, the hardened coating of Comparative Example 4 showed no scratches after 3500 cycles of rubbing, while the hardened coating of Example 1 showed no scratches after 4000 cycles of rubbing. Therefore, it can be seen that the compounding of difunctional polycarbonate-type polyurethane modified acrylate can improve the wear resistance and scratch resistance of the hardened coating.

[0105] Based on Examples 5 and Comparative Example 5, and referring to Tables 1-2, it can be seen that in the contact angle after 1000 eraser rubs, the change rate of Comparative Example 5 is -2.1°, while that of Example 5 is -3.1°. In the steel wool rubbing test, the hardened coating of Comparative Example 5 showed no scratches after 4100 rubs, while the hardened coating of Example 5 showed no scratches after 4000 rubs. The hardened coating prepared by replacing the trifunctional polyether-type polyurethane-modified acrylate with the trifunctional polyester-type polyurethane-modified acrylate exhibits relatively better wear resistance and scratch resistance. However, the hardened coating of Comparative Example 5 showed a decrease in resistance to neutral salt spray and adhesion after double 85 aging to 4B, and a color ΔE value of 1.36. The use of the trifunctional polyester-type polyurethane-modified acrylate deteriorates the weather resistance, salt spray corrosion resistance, and aging resistance of the hardened coating. Therefore, it can be concluded that the hardened coating with excellent comprehensive performance prepared by using the trifunctional polyether-type polyurethane-modified acrylate is more suitable as a protective coating for automotive windshields.

[0106] Based on Examples 1 and 6, and referring to Tables 1-2, it can be seen that the contact angle after 1000 eraser rubs was -2.0° for Comparative Example 6 and -2.3° for Example 1. In the steel wool rubbing test, the hardened coating of Comparative Example 6 showed no scratches after 4100 rubs, while the hardened coating of Example 1 showed no scratches after 4000 rubs. The hardened coating prepared by replacing the trifunctional polyether-type polyurethane modified acrylate with a trifunctional polyester-type polyurethane modified acrylate exhibits better wear resistance and scratch resistance. However, the hardened coating of Comparative Example 6 showed a decrease in resistance to neutral salt spray and adhesion after double 85 aging to 4B, and a color difference ΔE value of 1.28. The use of trifunctional polyester-type polyurethane modified acrylate deteriorates the weather resistance, salt spray corrosion resistance, and aging resistance of the hardened coating. Therefore, the hardened coating prepared using trifunctional polyether-type polyurethane modified acrylate has excellent comprehensive performance and is more suitable as a protective coating for automotive windshields.

[0107] Based on Example 1 and Comparative Example 7, and referring to Tables 1-2, it can be seen that in the contact angle after 1000 eraser rubs, Example 1 showed a change of only -2.3°, while Comparative Example 7 showed a change of -4.5°. In the steel wool rubbing test, the hardened coating of Comparative Example 7 showed no scratches after 3000 rubs, while the hardened coating of Example 1 showed no scratches after 4000 rubs. In terms of hardness, the hardness of the hardened coating of Comparative Example 7 was 6H, while the hardness of the hardened coating of Example 1 was 8H. It can be seen that replacing the hexafunctional polyether-type polyurethane-modified acrylate with the hexafunctional polycarbonate-type polyurethane-modified acrylate as the main crosslinking agent leads to a significant decrease in the hardness, wear resistance, and scratch resistance of the hardened coating. The hardened coating prepared with the hexafunctional polycarbonate-type polyurethane-modified acrylate as the main crosslinking agent has excellent wear resistance, scratch resistance, and weather resistance.

[0108] Based on Example 1 and Comparative Example 8, and referring to Tables 1-2, it can be seen that in the contact angle after 1000 eraser rubs, Example 1 showed a change of only -2.3°, while Comparative Example 8 showed a change of -3.3°. In the steel wool rubbing test, the hardened coating of Comparative Example 8 showed no scratches after 3500 rubs, while the hardened coating of Example 1 showed no scratches after 4000 rubs. Therefore, it can be seen that the hardened coating prepared by replacing the hexafunctional polycarbonate-type polyurethane-modified acrylate with commercially available hexafunctional aliphatic polyurethane as the main crosslinking agent has worse wear resistance and scratch resistance than the hardened coating prepared by using hexafunctional polycarbonate-type polyurethane-modified acrylate as the main crosslinking agent in Example 1. Furthermore, the color difference ΔE value of the hardened coating of Comparative Example 8 is 1.74, and its weather resistance and aging resistance are also inferior to the hardened coating prepared in Example 1. As can be seen from Example 1 and Comparative Examples 8-9 and Table 1-2, the hardened coating prepared by using the self-made hexafunctional polycarbonate-type polyurethane modified acrylate in this invention has excellent wear resistance, scratch resistance and weather resistance.

[0109] Based on Examples 1 and 9, and referring to Tables 1-2, it can be seen that the addition of hydrophobically modified nano-titanium oxynitride is beneficial to improving the wear resistance, scratch resistance, and yellowing resistance of the hardened coating. Based on Examples 1 and 10, and referring to Tables 1-2, it can be seen that the lack of thiol-SH groups on the surface of the hydrophobically modified nano-titanium oxynitride in Example 10 leads to a deviation in its adhesion stability to the hardened coating substrate. In the contact angle after 1000 cycles of rubber rubbing, the change rate of Comparative Example 10 was -3.0°, while that of Example 1 was only -2.3°. This indicates that the hardened coating prepared using the hydrophobically modified nano-titanium oxynitride in Example 10 exhibits a decrease in steel wool wear resistance and yellowing resistance, while the hardened coating prepared using the hydrophobically modified nano-titanium oxynitride in Example 5 shows relatively better wear resistance, scratch resistance, and yellowing resistance.

[0110] In summary, the hardened coating formed by the superhydrophobic and oleophobic curing coating configured in this invention and rapidly cured by ultraviolet light has advantages such as high adhesion, high hardness, high wear resistance, high stain resistance and durability, and high yellowing resistance, thereby enhancing the market competitiveness of automotive glass protective films.

[0111] It should be noted that this specific embodiment is merely an explanation of the technical solution of the present invention and is not intended to limit the present invention. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but as long as they are within the scope of the claims of the present invention, they are protected by patent law.

Claims

1. A UV-curable superhydrophobic and oleophobic curing coating, characterized in that: The UV-curable superhydrophobic and oleophobic hardening coating is made from the following raw materials in parts by weight: 2-6 parts of difunctional side-chain fluorinated polyester-type polyurethane modified acrylate, 10-40 parts of difunctional polycarbonate-type polyurethane modified acrylate, 15-30 parts of trifunctional polyether-type polyurethane modified acrylate, 5-50 parts of hexafunctional polycarbonate-type polyurethane modified acrylate, 100-180 parts of UV reactive diluent, 6-12 parts of photoinitiator, 0.5-3 parts of leveling agent, 0.5-4 parts of wetting agent, 0.5-3 parts of defoamer, and 0.5-8 parts of hydrophobic modified nano titanium oxynitride.

2. The UV-curable superhydrophobic and oleophobic curing coating according to claim 1, characterized in that: The difunctional side-chain fluorinated polyester-type polyurethane modified acrylate comprises an aliphatic diisocyanate, a side-chain fluorinated polyester diol, an organotin catalyst, an organic solvent, a polymerization inhibitor, and a capping agent; the aliphatic diisocyanate is at least one selected from isophorone diisocyanate (IPDI), dicyclohexylmethane diisocyanate (HMDI), norbornane diisocyanate (NBDI), and methylcyclohexyl diisocyanate (HTDI); the molar ratio of the isocyanate group -NCO in the aliphatic diisocyanate to the molar ratio of the hydroxyl group -OH in the side-chain fluorinated polyester diol is (1.5-2):1; the capping agent is at least one selected from hydroxyethyl methacrylate, hydroxypropyl methacrylate, and hydroxybutyl methacrylate.

3. The UV-curable superhydrophobic and oleophobic curing coating according to claim 2, characterized in that: The side-chain fluorinated polyester diol is composed of an alicyclic diol, 1,4-cyclohexanedicarboxylic acid, a fluorinated diol, and a titanate catalyst. The alicyclic diol is at least one selected from 2-cyclohexylpropane-1,3-diol, 1,4-cyclohexanediethanol, and 1,2-cyclododecanediol. The fluorinated diol is at least one selected from hexafluoropentanediol, octafluoro-1,6-hexanediol, and 2,2,3,3,4,4-hexafluoro-1,5-pentanediol. The ratio of the total molar amount of hydroxyl groups in the fluorinated diol and the alicyclic diol to the molar amount of carboxyl groups in the 1,4-cyclohexanedicarboxylic acid is (1.02-1.05):

1.

4. The UV-curable superhydrophobic and oleophobic curing coating according to claim 1, characterized in that: The hexafunctional polycarbonate-type polyurethane modified acrylate is made from aliphatic triisocyanate, polycarbonate diol, organotin catalyst, organic solvent, polymerization inhibitor, and end-capping agent; the polycarbonate diol includes at least one of polycarbonate diol with a molecular weight of 800-1500 as an initiator and polycarbonate diol with a mixed diol of 1,4-cyclohexanediol / 1,6-hexanediol as an initiator; the molar ratio of the isocyanate group -NCO in the aliphatic triisocyanate to the molar ratio of the hydroxyl group -OH in the polycarbonate diol is (1.5-2):1; the aliphatic triisocyanate is an HDI trimer and / or an IPDI trimer; the end-capping agent is 1-(acryloyloxy)-3-(methacryloyloxy)-2-propanol.

5. The UV-curable superhydrophobic and oleophobic curing coating according to claim 1, characterized in that: The photoinitiator is at least one of photoinitiator TPO, photoinitiator BP, photoinitiator 1173, photoinitiator 184, photoinitiator 2959, photoinitiator 819, and photoinitiator DETX.

6. The UV-curable superhydrophobic and oleophobic curing coating according to claim 1, characterized in that: The UV reactive diluent includes fluorinated UV reactive diluents, monofunctional UV reactive diluents, and polyfunctional UV reactive diluents. The fluorinated UV reactive diluent is at least one of (perfluorocyclohexyl) methacrylate, hexafluorobutyl methacrylate, hexafluorobutyl acrylate, octafluoropentyl methacrylate, and dodecafluoroheptyl methacrylate.

7. The UV-curable superhydrophobic and oleophobic curing coating according to claim 6, characterized in that: The monofunctional UV reactive diluent is at least one of butyl methacrylate, 2-ethylhexyl vinyl ether, tetrahydrofuran methyl methacrylate, isobornyl methacrylate, cyclohexyl methacrylate, 4-tert-butylcyclohexyl isobutylene acrylate, and 3-isobornylcyclohexyl acrylate.

8. The UV-curable superhydrophobic and oleophobic curing coating according to claim 6, characterized in that: The multifunctional UV reactive diluent is at least one of pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol hexaacrylate, trimethylolpropane triacrylate, hexanediol diacrylate, propoxylated neopentyl glycol diacrylate, and dipropylene glycol diacrylate.

9. The UV-curable superhydrophobic and oleophobic curing coating according to claim 6, characterized in that: The mass ratio of the fluorinated UV-active diluent to the difunctional side-chain fluorinated polyester polyurethane-modified acrylate is (0.8-2):1; the total weight of the fluorinated UV-active diluent and the difunctional side-chain fluorinated polyester polyurethane-modified acrylate is 5-10 parts.

10. A method for preparing a UV-curable superhydrophobic and oleophobic curing coating according to any one of claims 1-9, characterized in that: Includes the following steps: Under light-proof and nitrogen protection, accurately measured amounts of difunctional side-chain fluorinated polyester-type polyurethane-modified acrylate, difunctional polycarbonate-type polyurethane-modified acrylate, trifunctional polyether-type polyurethane-modified acrylate, hexafunctional polycarbonate-type polyurethane-modified acrylate, UV reactive diluent, leveling agent, wetting agent, defoamer, photoinitiator, and hydrophobic modified nano-titanium oxynitride are mixed evenly, filtered, discharged, and vacuum-packed to obtain a superhydrophobic and oleophobic curable coating. Finally, the obtained superhydrophobic and oleophobic curable coating is coated onto a base film, and after step-by-step heat treatment, it is UV cured with a cumulative light irradiation energy of 350-450 mJ / cm². After UV curing, a superhydrophobic and oleophobic curable coating is formed on the base film.

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