Ultraviolet-proof PET explosion-proof vehicle film and preparation method thereof

Abstract

The invention relates to the field of protective films, in particular to an ultraviolet-proof PET explosion-proof vehicle film and a preparation method thereof.The ultraviolet-proof PET explosion-proof vehicle film is formed by sequentially overlapping a wear-resistant PET layer, a sunscreen heat-insulating layer, a pressure-sensitive adhesive layer and a release layer from top to bottom; the sunscreen heat insulation layer is prepared from the following raw materials in parts by weight: 50 to 80 parts of modified polyurethane, 1 to 3 parts of light stabilizer, 0.5 to 1 part of carbon fiber, 0.3 to 0.5 part of silicon dioxide aerogel, 0.1 to 0.3 part of tin antimony oxide and 20 to 30 parts of N-methyl pyrrolidone. The anti-ultraviolet PET explosion-proof vehicle film prepared by the invention has excellent wear resistance, ultraviolet resistance and heat insulation performance and good transparency, and the preparation process is simple.

Description

Technical Field

[0001] The present invention relates to the field of protective films, and particularly to an anti-ultraviolet PET explosion-proof vehicle film and a preparation method thereof. Background Art

[0002] An explosion-proof vehicle film is simply a film layer pasted on automotive glass. It not only has the functions of heat insulation and light insulation, but also has the function of explosion protection, so it is called an explosion-proof film. The explosion-proof vehicle film has strong toughness and is equipped with a special pressure-sensitive adhesive. Once an accident occurs and the glass is broken, the glass fragments will be glued and will not fly and hurt people. However, in the current market, ordinary polyester films are mostly used, which cannot achieve full-function protection. Not only can they not resist ultraviolet and infrared light, resulting in poor heat insulation of the film, but also they are easily decomposed and aged under strong sunlight, leading to problems such as damage to the explosion-proof vehicle film and loss of protection effect.

[0003] Patent CN110802886A discloses a vehicle-used film and a preparation method thereof. The vehicle-used film is composed of the following layers from outside to inside: a matte film, a first adhesive layer, a printed film, a second adhesive layer, a graphite sheet, a third adhesive layer, a first PET transparent film, a fourth adhesive layer, a PET blue film, a silica gel layer, a second PET transparent film, and a self-adhesive tear-off label. This vehicle-used film has good tensile properties, aesthetics, and heat dissipation performance. However, most of the layers of this vehicle film need to be bonded by adhesive layers, resulting in a relatively complex process.

[0004] Patent CN112126370A discloses a vehicle-used heat insulation film, including a PET base layer, a sunscreen layer, a heat insulation and reflection layer, a dyed polyester layer, and a scratch-resistant layer. The upper surface of the PET base layer is provided with a heat insulation and reflection layer through an installation adhesive layer. The upper surface of the heat insulation and reflection layer is coated with a dyed polyester layer. The upper surface of the dyed polyester layer is provided with a sunscreen layer through a synthetic adhesive layer. The upper surface of the sunscreen layer is provided with a scratch-resistant layer. The lower surface of the PET base layer is provided with a release layer film through an adhesive layer. This solution effectively improves the blocking and absorption of ultraviolet rays, infrared rays and other light rays by the heat insulation film, reduces the influence of infrared rays on the heat insulation film, and at the same time reflects part of the sunlight back through the reflective film, further reducing the influence of sunlight and high temperature on the service life of the heat insulation film, improving the heat insulation effect, reducing the temperature inside the vehicle, and thus improving the comfortable environment inside the vehicle. However, its sunscreen layer is made of high-reflection sheet-like substances such as silver and titanium nitride, which may affect the transparency of the vehicle film.

[0005] Therefore, there is an urgent need in the market for a PET explosion-proof vehicle film with good transparency and a simple preparation process. Summary of the Invention

[0006] Aiming at the problems existing in the prior art, the purpose of the present invention is to obtain an anti-ultraviolet PET explosion-proof vehicle film with excellent wear resistance, anti-ultraviolet performance and heat insulation performance, good transparency and simple preparation process.

[0007] In order to achieve the above object, the technical solutions adopted by the present invention are as follows:

[0008] On the one hand, the present invention provides an anti-ultraviolet PET explosion-proof vehicle film, which is composed of a wear-resistant PET layer, a sunscreen and heat insulation layer, a pressure-sensitive adhesive layer and a release layer laminated in sequence from top to bottom; to prepare the sunscreen and heat insulation layer, by weight, it includes the following raw materials: 50-80 parts of modified polyurethane, 1-3 parts of light stabilizer, 0.5-1 part of carbon fiber, 0.3-0.5 part of silica aerogel, 0.1-0.3 part of antimony tin oxide, and 20-30 parts of N-methylpyrrolidone.

[0009] The anti-ultraviolet PET explosion-proof vehicle film obtained by sequentially laminating the wear-resistant PET layer with good transparency, the sunscreen and heat insulation layer, the pressure-sensitive adhesive layer and the release layer in this application has excellent wear resistance, anti-ultraviolet performance and heat insulation performance and good transparency.

[0010] In some embodiments, the preparation method of the modified polyurethane includes the following steps:

[0011] A1. Add isocyanate, polyester polyol and catalyst into a reaction vessel, stir at 70-80°C for 2-3 h under a nitrogen atmosphere, cool down to 50-60°C, add a chain extender and a solvent, stir for 1-2 h, add KH560 and hydroxyethyl acrylate, and continue to stir for 30-50 min, and then dry to obtain a polymer;

[0012] A2. Add the polymer obtained in step A1, azobisisobutyronitrile and a polymeric ultraviolet absorber into N-methyl-2-pyrrolidone, and react at 70-80°C for 3-5 h to obtain the modified polyurethane.

[0013] In some embodiments, the polymeric ultraviolet absorber is 2-hydroxy-4-methacryloyloxybenzophenone or 2-hydroxy-4-allyloxybenzophenone.

[0014] In this application, by using KH560 silane coupling agent containing epoxy group and hydroxyethyl acrylate containing hydroxyl group to modify polyurethane, -Si-OH bonds can be loaded on the polyurethane, so that carbon fiber, silica aerogel and antimony tin oxide can be evenly dispersed in the modified polyurethane through coupling action, which is beneficial to improving the anti-ultraviolet effect and heat insulation effect of the sunscreen and heat insulation layer. The introduction of the double bond structure enables it to react with the polymeric ultraviolet absorber, further improving the anti-ultraviolet effect of the sunscreen and heat insulation layer.

[0015] In some embodiments, the mass ratio of the isocyanate, polyester polyol, KH560, and hydroxyethyl acrylate is 1:(1 - 3):(0.05 - 0.15):(0.1 - 0.3).

[0016] Hydroxyethyl acrylate and KH560 have a capping effect on the polyurethane chain segment, which may affect its chain segment length and deteriorate the mechanical properties, heat resistance, anti-aging properties, adhesiveness, etc. of the modified polyurethane. By limiting the ratio of the isocyanate, polyester polyol, KH560, and hydroxyethyl acrylate in this application, while improving the UV protection effect and heat insulation effect of the sun protection and heat insulation layer, the basic properties of the polyurethane itself are not affected, which is beneficial to improving the adhesiveness between the sun protection and heat insulation layer, the wear-resistant PET layer, and the pressure-sensitive adhesive layer.

[0017] In some embodiments, the mass ratio of the polymer and the polymeric UV absorber in step A2 is 1:(0.1 - 0.3).

[0018] By limiting the ratio of the polymer and the polymeric UV absorber in this application, it can ensure that the UV absorption chain segments are evenly distributed on the modified polyurethane chain segments, which is beneficial to improving the UV protection performance of the explosion-proof vehicle film.

[0019] In some embodiments, the preparation method of the wear-resistant PET layer includes the following steps:

[0020] B1. Add tetraethyl orthosilicate, phenyltrimethoxysilane, γ-aminopropylmethyldiethoxysilane, deionized water, and glacial acetic acid into isopropanol, and react at 45 - 65 °C for 7 - 9 h to obtain an organosilicon resin.

[0021] B2. Coat the organosilicon resin obtained in step B1 on one side of the PET film and place it at 110 - 130 °C for 20 - 40 min to obtain the wear-resistant PET layer.

[0022] In this application, a layer of organosilicon resin is coated on the PET film to obtain the wear-resistant PET layer, which can improve the wear resistance and hardness of the PET film, reduce the damage of the external environment to the film layer, and is beneficial to improving the service life of the UV-protective PET explosion-proof vehicle film. By selecting phenyltrimethoxysilane as the raw material for preparing the organosilicon resin in this application, the organosilicon resin can produce a π-π conjugation effect with the PET layer, which is beneficial to improving the adhesion of the organosilicon resin on the PET film. And by adding γ-aminopropylmethyldiethoxysilane during the preparation of the organosilicon resin in this application, an amino group can be introduced onto the organosilicon resin, which is beneficial to improving the antistatic property of the surface of the PET vehicle film, reducing the adhesion of dust, and further improving the transparency of the PET vehicle film.

[0023] In some embodiments, the mass ratio of tetraethyl orthosilicate, phenyltrimethoxysilane, and γ-aminopropylmethyldiethoxysilane is (1 - 3):1:(0.2 - 0.4).

[0024] In some embodiments, the thickness of the silicone resin coating in step B2 is 3 - 6 μm.

[0025] Coating the silicone resin layer on the PET layer may affect its optical properties. In this application, by limiting the thickness of tetraethyl orthosilicate, phenyltrimethoxysilane, γ-aminopropylmethyldiethoxysilane, and the silicone resin coating, while improving the abrasion resistance of the PET film, its transparency can be ensured.

[0026] In some embodiments, the light stabilizer is one or more of o-hydroxybenzophenones, benzotriazoles, salicylate esters, triazines, and substituted acrylonitriles.

[0027] Preferably, the light stabilizer is benzotriazole.

[0028] In some embodiments, the average particle size of the carbon fiber is 150 - 200 nm.

[0029] In this application, by limiting the particle size of the carbon fiber, the heat resistance of the sunscreen and heat insulation layer can be improved. This may be because when the particle size of the carbon fiber is appropriate, it can form a "partition" during the sinking process of silica aerogel and antimony tin oxide in polyurethane, which is conducive to promoting the distribution of silica aerogel and antimony tin oxide in various parts of the modified polyurethane, and is conducive to improving the infrared absorption of the sunscreen and heat insulation layer, thereby improving its heat insulation performance.

[0030] On the other hand, the present invention provides a method for preparing an anti-ultraviolet PET explosion-proof vehicle film, comprising the following steps:

[0031] S1. Corona treatment is performed on the side of the wear-resistant PET layer that is not coated with silicone resin. The power of the corona treatment is 1 - 1.5 kW, and the frequency is 15 - 17 kHz, to obtain a PET film with single-sided corona treatment.

[0032] S2. Add carbon fiber to a partial amount of modified polyurethane and a partial amount of N-methylpyrrolidone, stir at room temperature for 20 - 30 min, and then stir at 300 - 500 r / min for 20 - 24 h to obtain solution A; add the light stabilizer, silica aerogel, and antimony tin oxide to the remaining amount of modified polyurethane and the remaining amount of N-methylpyrrolidone, stir at room temperature for 20 - 30 min, and then stir at 300 - 500 r / min for 20 - 24 h to obtain solution B.

[0033] S3. Coating solution A on the corona-treated surface of the single-sided corona-treated PET film obtained in step S1 to form layer A with a thickness of 5 - 15 μm. After drying, coat solution B on layer A, and after drying, obtain a sunscreen and heat-insulating layer with a thickness of 18 - 22 μm;

[0034] S4. Coating pressure-sensitive adhesive on the sunscreen and heat-insulating layer obtained in step S3. After coating, cure and age it. The aging temperature is 35 - 45 °C, and the aging time is 12 - 48 h. After forming the pressure-sensitive adhesive layer, obtain a sticky PET film;

[0035] S5. Unwind the release layer with a thickness of 25 ± 2 μm onto the sticky PET film obtained in step S4, wind up and press to obtain an anti-ultraviolet PET explosion-proof vehicle film.

[0036] In some embodiments, the preparation method of the release layer includes the following steps: coating a release agent on the surface of the release film, placing it in an oven at 100 - 150 °C, drying for 2 - 3 min, and winding up to obtain the release layer.

[0037] Compared with the prior art, the present invention has the following beneficial effects:

[0038] (1) The anti-ultraviolet PET explosion-proof vehicle film obtained by sequentially laminating the wear-resistant PET layer with good transparency, the sunscreen and heat-insulating layer, the pressure-sensitive adhesive layer and the release layer in the present invention has excellent wear resistance, anti-ultraviolet performance, heat-insulating performance and good transparency.

[0039] (2) By using KH560 silane coupling agent containing epoxy groups and 2-Hydroxyethyl acrylate containing hydroxyl groups to modify polyurethane in the present invention, -Si-OH bonds can be loaded on the polyurethane, so that carbon fiber, silica aerogel and antimony tin oxide can be evenly dispersed in the modified polyurethane through coupling, which is beneficial to improving the anti-ultraviolet effect and heat-insulating effect of the sunscreen and heat-insulating layer. The introduction of the double bond structure enables it to react with the polymeric ultraviolet absorber, further improving the anti-ultraviolet effect of the sunscreen and heat-insulating layer.

[0040] (3) Coating a layer of silicone resin on the PET film to obtain a wear-resistant PET layer in the present invention can improve the wear resistance and hardness of the PET film, reduce the damage of the external environment to the film layer, and is beneficial to improving the service life of the anti-ultraviolet PET explosion-proof vehicle film. By selecting phenyltrimethoxysilane as the raw material for preparing the silicone resin in this application, the silicone resin and the PET layer can produce a π-π conjugation effect, which is beneficial to improving the adhesion of the silicone resin on the PET film. And introducing an amine group on the silicone resin in this application is beneficial to improving the antistatic property of the surface of the PET vehicle film, reducing the adhesion of dust and further improving the transparency of the PET vehicle film. Specific embodiments

[0041] The present invention will be described below in conjunction with specific implementation embodiments. It should be noted that the following embodiments are examples of the present invention, only for explaining the present invention, and not for limiting the present invention. Other combinations and various improvements within the concept of the present invention can be made without departing from the gist or scope of the present invention.

[0042] In the following examples and comparative examples, except for the modified polyurethane and the wear-resistant PET layer, the other compounds and related reagents used can be purchased from the market. Among them, the thickness of the PET film is 25 ± 2 μm, purchased from Changzhou Lingke Electronic Technology Co., Ltd.; the release film is a PET release film with a thickness of 23 ± 2 μm, purchased from Dongguan Zhongshu New Material Technology Development Co., Ltd.; the model of the release agent is BMR-168, purchased from Fujian Blue Ocean Blackstone New Material Technology Co., Ltd.; the average particle size of carbon fiber-1 is 170 nm and the average particle size of carbon fiber-2 is 100 nm, both purchased from Zhongke Leiming (Beijing) Technology Co., Ltd.; the model of the fumed silica is HB-132, purchased from Hubei Huifu Nanomaterials Co., Ltd.; the average particle size of antimony tin oxide is 30 nm, purchased from Qinghe County Chaotai Metal Materials Co., Ltd.; the number average molecular weight of PBA polyester polyol is 1000, purchased from Shanghai Hongzhuang Chemical Technology Co., Ltd.; the pressure-sensitive adhesive is an acrylic pressure-sensitive adhesive, with the model Dow PS-8200, purchased from Shanghai Rongtai Chemical New Materials Co., Ltd.

[0043] Preparation Example 1

[0044] The preparation method of modified polyurethane-1 includes the following steps:

[0045] A1. Add 10 g of toluene diisocyanate, 20 g of PBA polyester polyol and DY-20 catalyst into a reaction vessel, stir at 75 °C for 2.5 h under a nitrogen atmosphere, cool down to 55 °C, add 1 g of 1,4-butanediol and 10 g of acetone and stir for 1.5 h, then add 1 g of KH560 and 2 g of hydroxyethyl acrylate and continue stirring for 40 min, and dry to obtain a polymer;

[0046] A2. Add 10 g of the polymer obtained in step A1, 0.1 g of azobisisobutyronitrile and 2 g of 2-hydroxy-4-allyloxybenzophenone into 30 g of N-methyl-2-pyrrolidone, and react at 75 °C for 4 h to obtain modified polyurethane-1.

[0047] Preparation Example 2

[0048] The preparation method of modified polyurethane-2 is the same as that of Preparation Example 1 in specific implementation, except that the addition amount of KH560 is 0.2 g.

[0049] Preparation Example 3

[0050] The preparation method of modified polyurethane-3 is the same as that of Preparation Example 1 in specific implementation manner, except that the addition amount of hydroxyethyl acrylate is 0.5 g.

[0051] Preparation Example 4

[0052] The preparation method of modified polyurethane-4 is the same as that of Preparation Example 1 in specific implementation manner, except that the addition amount of 2-hydroxy-4-allyloxybenzophenone is 5 g.

[0053] Preparation Example 5

[0054] The preparation method of polyurethane comprises the following steps: Add 10 g of toluene diisocyanate, 20 g of PBA polyester polyol and DY-20 catalyst into a reaction vessel, stir at 75 °C for 2.5 h under a nitrogen atmosphere, cool down to 55 °C, add 1 g of 1,4-butanediol and 10 g of acetone, and stir for 1.5 h to obtain polyurethane.

[0055] Preparation Example 6

[0056] The preparation method of wear-resistant PET layer-1 comprises the following steps:

[0057] B1. Add 2 g of tetraethyl orthosilicate, 1 g of phenyltrimethoxysilane, 0.3 g of γ-aminopropylmethyldiethoxysilane, 10 g of deionized water, 2 g of glacial acetic acid into 10 g of isopropanol, react at 55 °C for 8 h to obtain an organosilicon resin;

[0058] B2. Coat the organosilicon resin obtained in step B1 on one side of a PET film, the coating thickness of the organosilicon resin is 5 μm, and place it at 120 °C for 30 min to obtain wear-resistant PET layer-1.

[0059] Preparation Example 7

[0060] The preparation method of wear-resistant PET layer-2 is the same as that of Preparation Example 6 in specific implementation manner, except that the addition amount of γ-aminopropylmethyldiethoxysilane is 0.1 g.

[0061] Preparation Example 8

[0062] The preparation method of the release layer comprises the following steps: Coating a release agent on the surface of a release film, placing it in an oven at 125 °C, drying for 3 min, and winding it up to obtain the release layer

[0063] Example 1

[0064] An anti-ultraviolet PET explosion-proof vehicle film is composed of a wear-resistant PET layer, a sunscreen and heat-insulating layer, a pressure-sensitive adhesive layer and a release layer laminated in sequence from top to bottom; to prepare the sunscreen and heat-insulating layer, by weight, it includes the following raw materials: 65 parts of modified polyurethane-1, 2 parts of benzotriazole, 0.8 part of carbon fiber-1, 0.4 part of silica aerogel, 0.2 part of antimony tin oxide, and 25 parts of N-methylpyrrolidone.

[0065] The preparation method of the anti-ultraviolet PET explosion-proof vehicle film in this embodiment includes the following steps:

[0066] S1. Corona-treat the side of the wear-resistant PET layer without coated silicone resin through a corona device. The power of the corona treatment is 1.3 kW and the frequency is 16 kHz to obtain a single-sided corona-treated PET film;

[0067] S2. Add carbon fiber-1 to half of the modified polyurethane-1 and half of the N-methylpyrrolidone, stir at room temperature for 25 min, and then stir at 400 r / min for 22 h to obtain solution A; add benzotriazole, silica aerogel, and antimony tin oxide to the remaining modified polyurethane-1 and the remaining N-methylpyrrolidone, stir at room temperature for 25 min, and then stir at 400 r / min for 22 h to obtain solution B;

[0068] S3. Coating solution A on the corona-treated surface of the single-sided corona-treated PET film obtained in step S1 through an automatic coating device to form a layer A with a thickness of 10 μm. After drying, coat solution B on layer A, and after drying, obtain a sunscreen and heat-insulating layer with a thickness of 20 μm;

[0069] S4. Use an automatic coating device to coat a pressure-sensitive adhesive on the sunscreen and heat-insulating layer obtained in step S3. After coating, cure and age it. The aging temperature is 40 °C and the aging time is 30 h to form a pressure-sensitive adhesive layer and obtain a sticky PET film;

[0070] S5. Unroll a release layer with a thickness of 25 μm on the sticky PET film obtained in step S4, wind up and press it to obtain an anti-ultraviolet PET explosion-proof vehicle film with a thickness of 85 μm.

[0071] Example 2

[0072] An anti-ultraviolet PET explosion-proof vehicle film is composed of a wear-resistant PET layer, a sunscreen and heat-insulating layer, a pressure-sensitive adhesive layer and a release layer laminated in sequence from top to bottom; to prepare the sunscreen and heat-insulating layer, by weight, it includes the following raw materials: 50 parts of modified polyurethane-1, 1 part of benzotriazole, 0.5 part of carbon fiber-1, 0.3 part of silica aerogel, 0.1 part of antimony tin oxide, and 20 parts of N-methylpyrrolidone.

[0073] The preparation method of the anti-ultraviolet PET explosion-proof vehicle film in this embodiment includes the following steps:

[0074] S1. Corona-treat the side of the wear-resistant PET layer without coated silicone resin through a corona device. The power of the corona treatment is 1 kW and the frequency is 17 kHz to obtain a PET film with single-sided corona treatment.

[0075] S2. Add carbon fiber-1 to a partial amount of modified polyurethane-1 and a partial amount of N-methylpyrrolidone, stir at room temperature for 20 min, and then stir at 300 r / min for 24 h to obtain solution A; add benzotriazole, silica aerogel, and antimony tin oxide to the remaining amount of modified polyurethane and the remaining amount of N-methylpyrrolidone, stir at room temperature for 20 min, and then stir at 300 r / min for 24 h to obtain solution B.

[0076] S3. Coating solution A on the corona-treated side of the PET film with single-sided corona treatment obtained in step S1 through an automatic coating device to form a layer A with a thickness of 10 μm. After drying, coat solution B on layer A, and after drying, obtain a sunscreen and heat insulation layer.

[0077] S4. Coat pressure-sensitive adhesive on the sunscreen and heat insulation layer obtained in step S3 through an automatic coating device. After coating, cure and age it. The aging temperature is 35 °C and the aging time is 48 h. After forming a pressure-sensitive adhesive layer, obtain a sticky PET film.

[0078] S5. Unwind a release layer with a thickness of 25 μm on the sticky PET film obtained in step S4, wind up and press it to obtain an anti-ultraviolet PET explosion-proof vehicle film with a thickness of 85 μm.

[0079] Example 3

[0080] An anti-ultraviolet PET explosion-proof vehicle film is composed of a wear-resistant PET layer, a sunscreen and heat insulation layer, a pressure-sensitive adhesive layer and a release layer stacked from top to bottom in sequence; to prepare the sunscreen and heat insulation layer, by weight, it includes the following raw materials: 80 parts of modified polyurethane, 3 parts of benzotriazole, 1 part of carbon fiber-1, 0.5 part of silica aerogel, 0.3 part of antimony tin oxide, and 30 parts of N-methylpyrrolidone

[0081] The preparation method of the anti-ultraviolet PET explosion-proof vehicle film in this example includes the following steps:

[0082] S1. Corona-treat the side of the wear-resistant PET layer without coated silicone resin through a corona device. The power of the corona treatment is 1.5 kW and the frequency is 15 kHz to obtain a PET film with single-sided corona treatment.

[0083] S2. Add carbon fiber - 1 to a partial amount of modified polyurethane - 1 and a partial amount of N - methylpyrrolidone, stir at room temperature for 30 min, and then stir at 500 r / min for 20 h to obtain solution A; add benzotriazole, silica aerogel, and antimony tin oxide to the remaining amount of modified polyurethane and the remaining amount of N - methylpyrrolidone, stir at room temperature for 30 min, and then stir at 500 r / min for 20 h to obtain solution B;

[0084] S3. Coating solution A on the corona - treated surface of the single - sided corona - treated PET film obtained in step S1 through an automatic coating device to form an A layer with a thickness of 10 μm, drying, then coating solution B on the A layer, and drying to obtain a sunscreen and heat - insulation layer;

[0085] S4. Use an automatic coating device to coat a pressure - sensitive adhesive on the sunscreen and heat - insulation layer obtained in step S3. After coating, cure and age it. The aging temperature is 45 °C and the aging time is 12 h. After forming a pressure - sensitive adhesive layer, a sticky PET film is obtained;

[0086] S5. Unwind a release layer with a thickness of 25 μm onto the sticky PET film obtained in step S4, wind up and press it to obtain an anti - ultraviolet PET explosion - proof vehicle film with a thickness of 85 μm.

[0087] Example 4

[0088] An anti - ultraviolet PET explosion - proof vehicle film and its preparation method. The specific implementation method is the same as that of Example 1, except that carbon fiber - 1 is replaced with carbon fiber - 2 in equal amounts.

[0089] Example 5

[0090] An anti - ultraviolet PET explosion - proof vehicle film and its preparation method. The specific implementation method is the same as that of Example 1, except that modified polyurethane - 1 is replaced with modified polyurethane - 2 in equal amounts.

[0091] Example 6

[0092] An anti - ultraviolet PET explosion - proof vehicle film and its preparation method. The specific implementation method is the same as that of Example 1, except that modified polyurethane - 1 is replaced with modified polyurethane - 3 in equal amounts.

[0093] Example 7

[0094] An anti - ultraviolet PET explosion - proof vehicle film and its preparation method. The specific implementation method is the same as that of Example 1, except that modified polyurethane - 1 is replaced with modified polyurethane - 4 in equal amounts.

[0095] Example 8

[0096] An anti - ultraviolet PET explosion - proof vehicle film and its preparation method. The specific implementation method is the same as that of Example 1, except that wear - resistant PET layer - 1 is replaced with wear - resistant PET layer - 2 in equal amounts.

[0097] Comparative Example 1

[0098] An anti-ultraviolet PET explosion-proof vehicle film and its preparation method. The specific implementation is the same as that of Example 1, except that the modified polyurethane-1 is replaced with polyurethane in equal amount.

[0099] Comparative Example 2

[0100] An anti-ultraviolet PET explosion-proof vehicle film and its preparation method. The specific implementation is the same as that of Example 1, except that the wear-resistant PET layer-1 is replaced with a PET film in equal amount.

[0101] Performance Test

[0102] The following performance tests were carried out on the anti-ultraviolet PET explosion-proof vehicle films obtained from the above examples and comparative examples:

[0103] (1) Sunscreen and heat insulation performance and transparency: Use an S-45 Lambda950 ultraviolet-visible spectrophotometer, an S-47 Spectrum100 Fourier transform infrared spectrometer, and a Q-07WTH-A intelligent transmittance tester to test each vehicle film to judge the sunscreen and heat insulation performance and transparency of the vehicle film;

[0104] (2) Wear resistance: Place each vehicle film under 0000# steel wool with a load of 500 g and rub it back and forth 40 times. The grade with the number of scratches between 0 and 5 is excellent, the grade with the number of scratches between 6 and 10 is good, the grade with the number of scratches between 11 and 15 is medium, and the grade with the number of scratches ≥ 16 is poor.

[0105] The test results are shown in Table 1:

[0106] Table 1

[0107] Group Visible light transmittance % Ultraviolet transmittance % Total solar energy transmittance % Wear resistance Example 1 82 0.5 54.2 Excellent Example 2 81 0.7 53.7 Excellent Example 3 82 0.6 55.5 Excellent Example 4 75 0.9 57.3 Excellent Example 5 72 1.3 62.3 Excellent Example 6 74 1.1 59.6 Excellent Example 7 79 1.4 61.2 Excellent Example 8 68 0.8 55.7 Excellent Comparative Example 1 79 2.7 65.2 Excellent Comparative Example 2 78 0.8 53.8 Good

[0108] As can be seen from the data in Table 1, the anti-ultraviolet PET explosion-proof vehicle film in Examples 1-3 of the present invention has excellent wear resistance, anti-ultraviolet performance, heat insulation performance and good transparency. From the comparison between Example 4 and Example 1, it can be seen that changing the particle size of carbon fiber will prevent the carbon fiber from forming a "partition" during the sinking process of silica aerogel and antimony tin oxide in polyurethane, resulting in uneven distribution of substances that can exert heat insulation effect and infrared refraction effect, leading to deterioration of the transparency, anti-ultraviolet performance and heat insulation performance of the vehicle film; from the comparison between Examples 5, 6 and Example 1, it can be seen that changing the ratio of isocyanate, polyester polyol, KH560 and hydroxyethyl acrylate will deteriorate the loading capacity of modified polyurethane for silica aerogel, antimony tin oxide and carbon fiber, resulting in deterioration of the transparency, anti-ultraviolet performance and heat insulation performance of the vehicle film; from the comparison between Example 7 and Example 1, it can be seen that changing the ratio of polymer and polymeric ultraviolet absorber will lead to uneven distribution of ultraviolet absorption segments, resulting in a decrease in the anti-ultraviolet performance of the vehicle film; from the comparison between Example 8 and Example 1, it can be seen that changing the ratio of tetraethyl orthosilicate, phenyltrimethoxysilane and γ-aminopropylmethyldiethoxysilane will cause dust to easily adhere to the vehicle film, resulting in a decrease in the transparency of the vehicle film; from the comparison between Comparative Example 1 and Example 1, it can be seen that without modifying the polyurethane, the anti-ultraviolet performance and heat insulation performance of the vehicle film deteriorate; from the comparison between Comparative Example 2 and Example 1, it can be seen that directly using a PET film, the wear resistance of the vehicle film is poor.

[0109] The above embodiments are only for illustrating the technical concept and features of the present invention, and the purpose is to enable those who are familiar with this technology to understand the content of the present invention and implement it. It cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit and essence of the present invention should be covered within the protection scope of the present invention.

Claims

1. A UV-proof PET explosion-proof car film, characterized in that: The invention is composed of a wear-resistant PET layer, a sunscreen and heat-insulating layer, a pressure-sensitive adhesive layer and a release layer stacked in sequence from top to bottom; the sunscreen and heat-insulating layer is prepared from the following raw materials, measured by weight: 50-80 parts of modified polyurethane, 1-3 parts of light stabilizer, 0.5-1 part of carbon fiber, 0.3-0.5 parts of silica aerogel, 0.1-0.3 parts of antimony tin oxide and 20-30 parts of N-methylpyrrolidone.

2. The anti-ultraviolet PET explosion-proof car film according to claim 1, characterized in that: The preparation method of the modified polyurethane comprises the following steps: A1. Add isocyanate, polyester polyol and catalyst into a reaction vessel, stir at 70-80°C for 2-3h under nitrogen atmosphere, cool to 50-60°C, add chain extender and solvent, stir for 1-2h, add KH560 and hydroxyethyl acrylate, continue stirring for 30-50min, and dry to obtain a polymer; A2. Add the polymer obtained in step A1, azobisisobutyronitrile and polymeric ultraviolet absorber to N-methyl-2-pyrrolidone, and react at 70-80° C. for 3-5 hours to obtain modified polyurethane.

3. The anti-ultraviolet PET explosion-proof car film according to claim 2, characterized in that: The mass ratio of the isocyanate, polyester polyol, KH560 and hydroxyethyl acrylate is 1:(1-3):(0.05-0.15):(0.1-0.3).

4. The anti-ultraviolet PET explosion-proof car film according to claim 2, characterized in that: The mass ratio of the polymer to the polymeric ultraviolet absorber is 1:(0.1-0.3).

5. The anti-ultraviolet PET explosion-proof car film according to claim 2, characterized in that: The polymeric ultraviolet absorber is 2-hydroxy-4-methacryloxybenzophenone or 2-hydroxy-4-allyloxybenzophenone.

6. The anti-ultraviolet PET explosion-proof car film according to claim 1, characterized in that: The preparation method of the wear-resistant PET layer comprises the following steps: B1. Add ethyl orthosilicate, phenyltrimethoxysilane, γ-aminopropylmethyldiethoxysilane, deionized water and glacial acetic acid to isopropanol, and react at 45-65° C. for 7-9 hours to obtain a silicone resin; B2. Coat the organic silicone resin obtained in step B1 on one side of the PET film and place it at 110-130° C. for 20-40 min to obtain a wear-resistant PET layer.

7. The anti-ultraviolet PET explosion-proof car film according to claim 6, characterized in that: The mass ratio of the tetraethyl orthosilicate, phenyltrimethoxysilane and γ-aminopropylmethyldiethoxysilane is (1-3):1:(0.2-0.4).

8. The anti-ultraviolet PET explosion-proof car film according to claim 6, characterized in that: The thickness of the silicone resin coating in step B2 is 3-6 μm.

9. The anti-ultraviolet PET explosion-proof car film according to claim 1, characterized in that: The average particle size of the carbon fiber is 150-200 nm.

10. A method for preparing the UV-proof PET explosion-proof vehicle film according to any one of claims 1 to 9, characterized in that: The following steps are involved: S1, performing corona treatment on the side of the wear-resistant PET layer that is not coated with the silicone resin, the power of the corona treatment is 1-1.5kW, and the frequency is 15-17kHz, to obtain a single-sided corona PET film; S2, adding carbon fiber to a part of the modified polyurethane and a part of N-methylpyrrolidone, stirring at room temperature for 20-30 minutes, and then stirring at 300-500r / min for 20-24 hours to obtain solution A; adding light stabilizer, silica aerogel, and antimony tin oxide to the remaining amount of modified polyurethane and the remaining amount of N-methylpyrrolidone, stirring at room temperature for 20-30 minutes, and then stirring at 300-500r / min for 20-24 hours to obtain solution B; S3, coating the corona surface of the single-sided corona PET film obtained in step S1 with solution A to form a layer A with a thickness of 5-15 μm, and coating the layer A with solution B after drying to obtain a sunscreen and heat-insulating layer with a thickness of 18-22 μm after drying; S4, coating a pressure-sensitive adhesive on the sunscreen and heat-insulating layer obtained in step S3, curing and aging the coating, wherein the aging temperature is 35-45° C. and the aging time is 12-48 hours, and a viscous PET film is obtained after forming a pressure-sensitive adhesive layer; S5. Unwind the release layer with a thickness of 25±2 μm on the sticky PET film obtained in step S4, and rewind and press to obtain an anti-ultraviolet PET explosion-proof car film with a thickness of 85±2 μm.