High-weatherability retroreflective film and method of making same

Abstract

The application relates to the technical field of traffic safety, in particular to a high-weather-resistance reflective film and a manufacturing method thereof. The high-weather-resistance reflective film comprises a PET film, a reflective adhesive layer coated on the surface of the PET film, and a silicone coating layer coated on the surface of the adhesive layer; the reflective adhesive layer is formed by uniformly scattering glass beads on the surface of the PET film after the adhesive material is coated on the surface of the PET film; the raw material of the adhesive material comprises, by mass fraction, 50-150 parts of a hydroxyl-containing acrylate resin, 5-12 parts of an IPDI prepolymer, 1-2 parts of UV329 ultraviolet absorber, and 0.5-1.5 parts of anti-aging agent 1076. The reflective film has excellent self-cleaning performance, good reflectivity, long-term stable weather resistance, can effectively reflect incident light, effectively protects the reflective glass beads, can maintain the performance for a long time under various environments and conditions, and is suitable for being used as a traffic sign.

Description

Technical Field

[0001] This invention relates to the field of traffic safety technology, and in particular to a high weather-resistant reflective film and its manufacturing method. Background Technology

[0002] As a retroreflective material, reflective film significantly improves the visibility of objects in low-light environments by directionally reflecting light back towards the light source. It is widely used in road traffic signs, vehicle safety markings, outdoor advertising, and equipment indicators. With the continuous growth of global traffic flow and the increasing demand for nighttime driving safety, reflective film has become one of the key basic materials for modern traffic safety management.

[0003] Currently, mainstream reflective films form an aluminum reflective layer behind a glass microsphere layer using a vacuum evaporation process, utilizing the refraction and reflection of the microspheres to allow light to return. However, the aluminum layer is directly exposed to the environment and is susceptible to oxidation, moisture penetration, and chemical corrosion, causing its reflective performance to degrade over time. Furthermore, the bonding force between the aluminum layer and the microspheres is limited, leading to peeling and detachment after prolonged use, significantly shortening the product's lifespan. Additionally, traditional reflective films often use general-purpose polymer materials such as PET, PVC, or PC on their surfaces. While these materials possess a certain mechanical strength, their weather resistance is insufficient. Long-term exposure to ultraviolet radiation, temperature and humidity changes, and pollutants can cause yellowing, embrittlement, and even cracking, failing to meet the long-term service requirements of harsh outdoor environments.

[0004] In addition, existing products generally lack self-cleaning functions, and their surfaces are prone to adhering to pollutants such as dust and oil, which further reduces reflectivity. These problems together restrict the promotion and application of reflective films in high-value-added fields, and there is an urgent need to develop reflective films that have both long-lasting weather resistance and stable reflective performance. Summary of the Invention

[0005] The purpose of this invention is to address the shortcomings of existing technologies by proposing a high weather-resistant reflective film and its manufacturing method.

[0006] A high weather-resistant reflective film includes: a PET film, a reflective adhesive layer covering the surface of the PET film, and an organosilicon coating covering the surface of the adhesive layer; the reflective adhesive layer is formed by uniformly spreading glass microspheres after coating the PET film surface with adhesive material; the adhesive material raw materials include, by weight, 50-150 parts of hydroxyl-containing acrylate resin, 5-12 parts of IPDI prepolymer, 1-2 parts of UV329 ultraviolet absorber, and 0.5-1.5 parts of antioxidant 1076.

[0007] Preferably, the mass ratio of glass microspheres to adhesive material is 2-3:10.

[0008] Preferably, the glass microspheres have a particle size of 10-50 μm.

[0009] Preferably, the raw materials for the organosilicon coating include, by weight, 5-10 parts of vinyl-terminated polydimethylsiloxane, 1-3 parts of trifluoropropylmethylcyclotrisiloxane, 1-5 parts of activated nano-silica, 1-3 parts of pentaerythritol tetra-3-mercaptopropionate, and 0.1-0.4 parts of 2-hydroxy-2-methylphenylacetone.

[0010] More preferably, activated nano-silica is prepared by the following steps: nano-silica is added to an ethanol aqueous solution and ultrasonically dispersed for 1-2 hours, the pH of the system is adjusted to 4-5, a silane coupling agent is added and stirred for 20-40 minutes, perfluorooctyltrichlorosilane is added and stirred for 5-15 minutes, refluxed at 60-70°C for 2-5 hours, centrifuged, washed with water, and vacuum dried.

[0011] Specifically, the mass ratio of nano-silica, silane coupling agent, and perfluorooctyltrichlorosilane is 10-20:0.1-0.4:0.1-0.2.

[0012] Specifically, the ultrasonic frequency is 60-70kHz.

[0013] The manufacturing method of the above-mentioned high weather-resistant reflective film includes the following steps: S1. Hydroxyl-containing acrylate resin, IPDI prepolymer, UV329 ultraviolet absorber, antioxidant 1076, and ethyl acetate are mixed evenly to obtain an adhesive material. S2. Perform corona treatment on the PET film surface for 30-60 seconds, with a corona power of 5-8 kW / m. 2 Apply adhesive material to the surface of the corona-treated PET film, let it stand for 5-7 minutes, evenly sprinkle glass microspheres, let it stand for 10-20 minutes to obtain the pretreated base layer; S3. Add vinyl-terminated polydimethylsiloxane, trifluoropropylmethylcyclotrisiloxane, activated nano-silica, pentaerythritol tetra-3-mercaptopropionate, and 2-hydroxy-2-methylphenylacetone to dichloromethane and stir until homogeneous. Then spray the mixture onto the pretreated substrate surface and cure under ultraviolet light for 1-1.5 hours at an ultraviolet light intensity of 400-500 mW / cm². 2 Grind at 50-100℃ for 5-10 hours.

[0014] Preferably, in S2, the adhesive material coating thickness is 20-30 μm.

[0015] Preferably, in S3, the coating thickness is 30-40 μm.

[0016] Compared with existing technologies, the present invention has the following advantages: The adhesive material used in this invention is a compound of UV329 ultraviolet absorber and antioxidant 1076, which effectively blocks ultraviolet erosion and inhibits free radical reactions. Combined with the corona treatment of the PET base layer, it enhances the interfacial bonding force and delays the yellowing and embrittlement process of the material. The surface layer is a low surface energy organosilicon coating constructed from vinyl-terminated polydimethylsiloxane and fluorinated siloxane monomers. Combined with the composite rough structure formed by activated nano-silica and glass microspheres, it gives the film excellent resistance to water vapor penetration and chemical corrosion, excellent superhydrophobic effect, and excellent self-cleaning effect, which greatly improves the stability of long-term outdoor service.

[0017] This invention utilizes activated nano-silica uniformly dispersed within an organosilicon network, secured by covalent bonds to prevent detachment. The resulting microscopic uneven structure, synergistically formed with glass microspheres, significantly reduces surface energy, making it difficult for dust and oil to adhere. Rainwater washes away dirt, ensuring long-lasting and stable reflectivity. The glass microspheres are fixed to the substrate surface by an adhesive material and protected by an organosilicon coating, effectively reducing light scattering loss and maintaining high retroreflective efficiency. The adhesive material applied to the substrate surface effectively improves the bonding strength between the PET substrate and the organosilicon coating. After curing, this significantly enhances long-term weather resistance and provides excellent long-term protection.

[0018] The reflective film of this invention not only has excellent self-cleaning properties, but also achieves good reflectivity and long-term stable weather resistance. It can effectively reflect incident light and effectively protect reflective glass microspheres. It can maintain its performance for a long time under various environments and conditions, making it suitable for use as a traffic sign. It can also maintain excellent adhesion when multi-layer reflective film is laminated, which greatly expands its application range and commercial value. Attached Figure Description

[0019] Figure 1 The image shows a comparison of the static water contact angle and peel strength of the reflective films obtained in Example 5 and Comparative Examples 1-2.

[0020] Figure 2 The graph shows a comparison of the reflectivity of the reflective films obtained in Example 5 and Comparative Examples 1-2 before and after simulated solar radiation. Detailed Implementation

[0021] The present invention will now be described in further detail with reference to specific embodiments. The given embodiments are merely illustrative of the invention and not intended to limit its scope. The embodiments provided below can serve as a guide for further improvements by those skilled in the art and do not constitute a limitation on the invention in any way.

[0022] Unless otherwise specified, the experimental methods used in the following examples are conventional methods, performed according to the techniques or conditions described in the literature in this field or according to the product instructions. Unless otherwise specified, the materials and reagents used in the following examples are commercially available.

[0023] The PET film used below was purchased from Hangzhou Limtech Technology Co., Ltd., with a thickness of 80±5μm. The glass microspheres used below were purchased from Shijiazhuang Jiude Mineral Products Co., Ltd., with a particle size of 10-50μm. The hydroxyl-containing acrylate resin used below was sourced from Covestro, under the brand name Bayhydrol. ® A 2470. The IPDI prepolymer used below was purchased from Jining Fangyu Chemical Co., Ltd., model WD-8670. The vinyl-terminated polydimethylsiloxane (Vi-PDMS) used below was purchased from Hubei Xinyuhong Biomedical Technology Co., Ltd.

[0024] Example 1 A high weather-resistant reflective film includes: a PET film, a reflective adhesive layer covering the surface of the PET film, and an organosilicon coating covering the surface of the adhesive layer; the reflective adhesive layer is formed by uniformly spreading glass microspheres after coating the PET film surface with adhesive material.

[0025] The adhesive material raw materials include: 50g of hydroxyl-containing acrylate resin, 5g of IPDI prepolymer, 1g of UV329 ultraviolet absorber, and 0.5g of antioxidant 1076. The mass ratio of glass microspheres to adhesive material is 1:5.

[0026] The raw materials for the silicone coating include: 5g of vinyl-terminated polydimethylsiloxane, 1g of trifluoropropylmethylcyclotrisiloxane, 1g of activated nano-silica, 1g of pentaerythritol tetra-3-mercaptopropionate, and 0.1g of 2-hydroxy-2-methylphenylacetone.

[0027] Activated nano-silica was prepared using the following steps: 10g of nano-silica was added to 50g of a 40% (w / w) aqueous ethanol solution and ultrasonically dispersed for 1h at a frequency of 60kHz. The pH of the system was adjusted to 4-5 using a 1mol / L acetic acid solution. 0.1g of KH570 coupling agent was added and stirred for 20min. 0.1g of perfluorooctyltrichlorosilane was added and stirring was continued for 5min. The mixture was then refluxed at 60℃ for 2h, centrifuged, and the product was washed twice with deionized water and vacuum dried.

[0028] The manufacturing method of the above-mentioned high weather-resistant reflective film includes the following steps: S1. Hydroxyl-containing acrylate resin, IPDI prepolymer, UV329 ultraviolet absorber, antioxidant 1076, and 20g of ethyl acetate are mixed evenly to obtain an adhesive material. S2. Perform corona treatment on the PET film surface for 30 seconds, with a corona power of 5kW / m. 2 The adhesive material is applied to the substrate surface with a thickness of 20μm and left to stand for 5 minutes. Glass microspheres are then evenly sprinkled and left to stand for 10 minutes to obtain the pretreated substrate. S3. Add vinyl-terminated polydimethylsiloxane, trifluoropropylmethylcyclotrisiloxane, activated nano-silica, pentaerythritol tetra-3-mercaptopropionate, and 2-hydroxy-2-methylphenylacetone to 50g of dichloromethane and stir until homogeneous. Spray the mixture onto the pretreated substrate surface to a thickness of 30μm. Cure under ultraviolet light for 1 hour at an ultraviolet light intensity of 400mW / cm². 2 ; rewind and mature at 70℃ for 5 hours.

[0029] Example 2 A high weather-resistant reflective film includes: a PET film, a reflective adhesive layer covering the surface of the PET film, and an organosilicon coating covering the surface of the adhesive layer; the reflective adhesive layer is formed by uniformly spreading glass microspheres after coating the PET film surface with adhesive material.

[0030] The adhesive material raw materials include: 150g of hydroxyl-containing acrylate resin, 12g of IPDI prepolymer, 2g of UV329 ultraviolet absorber, and 1.5g of antioxidant 1076. The mass ratio of glass microspheres to adhesive material is 3:10.

[0031] The raw materials for the organosilicon coating include: 10g of vinyl-terminated polydimethylsiloxane, 3g of trifluoropropylmethylcyclotrisiloxane, 5g of activated nano-silica, 3g of pentaerythritol tetra-3-mercaptopropionate, and 0.4g of 2-hydroxy-2-methylphenylacetone.

[0032] Activated nano-silica was prepared using the following steps: 20g of nano-silica was added to 120g of a 60% ethanol aqueous solution and ultrasonically dispersed for 2h at a frequency of 70kHz. The pH of the system was adjusted to 4-5 using a 2mol / L acetic acid solution. 0.4g of KH570 coupling agent was added and stirred for 40min. 0.2g of perfluorooctyltrichlorosilane was added and stirred for another 15min. The mixture was then refluxed at 70℃ for 5h, centrifuged, and the product was washed four times with deionized water and vacuum dried.

[0033] The manufacturing method of the above-mentioned high weather-resistant reflective film includes the following steps: S1. Hydroxyl-containing acrylate resin, IPDI prepolymer, UV329 ultraviolet absorber, antioxidant 1076, and 30g of ethyl acetate are mixed evenly to obtain an adhesive material. S2. Perform corona treatment on the PET film surface for 60 seconds, with a corona power of 8kW / m. 2The adhesive material is applied to the substrate surface with a thickness of 30μm and left to stand for 7 minutes. Glass microspheres are then evenly sprinkled and left to stand for 20 minutes to obtain the pretreated substrate. S3. Add vinyl-terminated polydimethylsiloxane, trifluoropropylmethylcyclotrisiloxane, activated nano-silica, pentaerythritol tetra-3-mercaptopropionate, and 2-hydroxy-2-methylphenylacetone to 150g of dichloromethane and stir until homogeneous. Spray the mixture onto the pretreated substrate surface to a thickness of 40μm. Cure under ultraviolet light for 1.5h at an ultraviolet light intensity of 500mW / cm². 2 ; rewind and cure at 90℃ for 10 hours.

[0034] Example 3 A high weather-resistant reflective film includes: a PET film, a reflective adhesive layer covering the surface of the PET film, and an organosilicon coating covering the surface of the adhesive layer; the reflective adhesive layer is formed by uniformly spreading glass microspheres after coating the PET film surface with adhesive material.

[0035] The adhesive material raw materials include: 80g of hydroxyl-containing acrylate resin, 10g of IPDI prepolymer, 1.2g of UV329 ultraviolet absorber, and 1.2g of antioxidant 1076. The mass ratio of glass microspheres to adhesive material is 1.1:5.

[0036] The raw materials for the organosilicon coating include: 9g of vinyl-terminated polydimethylsiloxane, 1.5g of trifluoropropylmethylcyclotrisiloxane, 4g of activated nano-silica, 1.5g of pentaerythritol tetra-3-mercaptopropionate, and 0.2g of 2-hydroxy-2-methylphenylacetone.

[0037] Activated nano-silica was prepared using the following steps: 18g of nano-silica was added to 60g of a 55% (w / w) aqueous ethanol solution and ultrasonically dispersed for 80min at a frequency of 68kHz. The pH of the system was adjusted to 4-5 using a 1.2mol / L acetic acid solution. 0.3g of KH570 coupling agent was added and stirred for 25min. 0.18g of perfluorooctyltrichlorosilane was added and stirring was continued for 8min. The mixture was then refluxed at 68℃ for 3h, centrifuged, and the product was washed three times with deionized water and vacuum dried.

[0038] The manufacturing method of the above-mentioned high weather-resistant reflective film includes the following steps: S1. Hydroxyl-containing acrylate resin, IPDI prepolymer, UV329 ultraviolet absorber, antioxidant 1076, and 28g of ethyl acetate are mixed evenly to obtain an adhesive material. S2. Perform corona treatment on the PET film surface for 40 seconds, with a corona power of 7kW / m. 2The adhesive material is applied to the substrate surface with a thickness of 25μm and left to stand for 5.5 minutes. Glass microspheres are then evenly sprinkled and left to stand for 18 minutes to obtain the pretreated substrate. S3. Add vinyl-terminated polydimethylsiloxane, trifluoropropylmethylcyclotrisiloxane, activated nano-silica, pentaerythritol tetra-3-mercaptopropionate, and 2-hydroxy-2-methylphenylacetone to 80g of dichloromethane and stir until homogeneous. Spray the mixture onto the pretreated substrate surface to a thickness of 35μm. Cure under ultraviolet light for 1.3h at an ultraviolet light intensity of 420mW / cm². 2 ; rewind and mature at 60℃ for 7 hours.

[0039] Example 4 A high weather-resistant reflective film includes: a PET film, a reflective adhesive layer covering the surface of the PET film, and an organosilicon coating covering the surface of the adhesive layer; the reflective adhesive layer is formed by uniformly spreading glass microspheres after coating the PET film surface with adhesive material.

[0040] The adhesive material raw materials include: 120g of hydroxyl-containing acrylate resin, 6g of IPDI prepolymer, 1.8g of UV329 ultraviolet absorber, and 0.8g of antioxidant 1076. The mass ratio of glass microspheres to adhesive material is 1.4:5.

[0041] The raw materials for the organosilicon coating include: 7g of vinyl-terminated polydimethylsiloxane, 2.5g of trifluoropropylmethylcyclotrisiloxane, 2g of activated nano-silica, 2.5g of pentaerythritol tetra-3-mercaptopropionate, and 0.3g of 2-hydroxy-2-methylphenylacetone.

[0042] Activated nano-silica was prepared using the following steps: 12g of nano-silica was added to 100g of a 45% (w / w) aqueous ethanol solution and ultrasonically dispersed for 100min at a frequency of 62kHz. The pH of the system was adjusted to 4-5 using a 1.8mol / L acetic acid solution. 0.2g of KH570 coupling agent was added and stirred for 35min. 0.12g of perfluorooctyltrichlorosilane was added and stirring was continued for 12min. The mixture was then refluxed at 62℃ for 4h, centrifuged, and the product was washed three times with deionized water and vacuum dried.

[0043] The manufacturing method of the above-mentioned high weather-resistant reflective film includes the following steps: S1. Hydroxyl-containing acrylate resin, IPDI prepolymer, UV329 ultraviolet absorber, antioxidant 1076, and 22g of ethyl acetate are mixed evenly to obtain an adhesive material. S2. Perform corona treatment on the PET film surface for 50 seconds, with a corona power of 6kW / m. 2The adhesive material is applied to the substrate surface with a thickness of 25μm and left to stand for 6.5 minutes. Glass microspheres are then evenly sprinkled and left to stand for 12 minutes to obtain the pretreated substrate. S3. Add vinyl-terminated polydimethylsiloxane, trifluoropropylmethylcyclotrisiloxane, activated nano-silica, pentaerythritol tetra-3-mercaptopropionate, and 2-hydroxy-2-methylphenylacetone to 120g of dichloromethane and stir until homogeneous. Spray the mixture onto the pretreated substrate surface to a thickness of 35μm. Cure under ultraviolet light for 1.1h at an ultraviolet light intensity of 480mW / cm². 2 ; rewind and mature at 60℃ for 9 hours.

[0044] Example 5 A high weather-resistant reflective film includes: a PET film, a reflective adhesive layer covering the surface of the PET film, and an organosilicon coating covering the surface of the adhesive layer; the reflective adhesive layer is formed by uniformly spreading glass microspheres after coating the PET film surface with adhesive material.

[0045] The adhesive material raw materials include: 100g of hydroxyl-containing acrylate resin, 8g of IPDI prepolymer, 1.5g of UV329 ultraviolet absorber, and 1g of antioxidant 1076. The mass ratio of glass microspheres to adhesive material is 1:4.

[0046] The raw materials for the silicone coating include: 8g of vinyl-terminated polydimethylsiloxane, 2g of trifluoropropylmethylcyclotrisiloxane, 3g of activated nano-silica, 2g of pentaerythritol tetra-3-mercaptopropionate, and 0.25g of 2-hydroxy-2-methylphenylacetone.

[0047] Activated nano-silica was prepared using the following steps: 15g of nano-silica was added to 80g of a 50% (w / w) aqueous ethanol solution and ultrasonically dispersed for 90min at a frequency of 65kHz. The pH of the system was adjusted to 4-5 using a 1.5mol / L acetic acid solution. 0.25g of KH570 coupling agent was added and stirred for 30min. 0.15g of perfluorooctyltrichlorosilane was added and stirred for another 10min. The mixture was then refluxed at 65℃ for 3.5h, centrifuged, and the product was washed three times with deionized water and vacuum dried.

[0048] The manufacturing method of the above-mentioned high weather-resistant reflective film includes the following steps: S1. Hydroxyl-containing acrylate resin, IPDI prepolymer, UV329 ultraviolet absorber, antioxidant 1076, and 25g of ethyl acetate are mixed evenly to obtain an adhesive material. S2. Perform corona treatment on the PET film surface for 45 seconds, with a corona power of 6.5 kW / m. 2The adhesive material is applied to the substrate surface with a thickness of 25μm and left to stand for 6 minutes. Glass microspheres are then evenly sprinkled and left to stand for 15 minutes to obtain the pretreated substrate. S3. Add vinyl-terminated polydimethylsiloxane, trifluoropropylmethylcyclotrisiloxane, activated nano-silica, pentaerythritol tetra-3-mercaptopropionate, and 2-hydroxy-2-methylphenylacetone to 100g of dichloromethane and stir until homogeneous. Spray the mixture onto the pretreated substrate surface to a thickness of 35μm. Cure under ultraviolet light for 1.2h at an ultraviolet light intensity of 450mW / cm². 2 ; rewind and mature at 65℃ for 8 hours.

[0049] Comparative Example 1 A high weather-resistant reflective film includes: a PET film, a reflective adhesive layer covering the surface of the PET film, and an organosilicon coating covering the surface of the adhesive layer; the reflective adhesive layer is formed by uniformly spreading glass microspheres after coating the PET film surface with adhesive material.

[0050] The adhesive material raw materials include: 100g of hydroxyl-containing acrylate resin, 8g of IPDI prepolymer, 1.5g of UV329 ultraviolet absorber, and 1g of antioxidant 1076. The mass ratio of glass microspheres to adhesive material is 1:4.

[0051] The raw materials for the silicone coating include: 8g of vinyl-terminated polydimethylsiloxane, 2g of trifluoropropylmethylcyclotrisiloxane, 3g of nano-silica, 2g of pentaerythritol tetra-3-mercaptopropionate, and 0.25g of 2-hydroxy-2-methylphenylacetone.

[0052] The manufacturing method of the above-mentioned high weather-resistant reflective film includes the following steps: S1. Hydroxyl-containing acrylate resin, IPDI prepolymer, UV329 ultraviolet absorber, antioxidant 1076, and 25g of ethyl acetate are mixed evenly to obtain an adhesive material. S2. Perform corona treatment on the PET film surface for 45 seconds, with a corona power of 6.5 kW / m. 2 The adhesive material is applied to the substrate surface with a thickness of 25μm and left to stand for 6 minutes. Glass microspheres are then evenly sprinkled and left to stand for 15 minutes to obtain the pretreated substrate. S3. Add vinyl-terminated polydimethylsiloxane, trifluoropropylmethylcyclotrisiloxane, nano-silica, pentaerythritol tetra-3-mercaptopropionate, and 2-hydroxy-2-methylphenylacetone to 100g of dichloromethane and stir until homogeneous. Spray the mixture onto the pretreated substrate surface to a thickness of 35μm. Cure under ultraviolet light for 1.2h at an ultraviolet light intensity of 450mW / cm². 2 ; rewind and mature at 65℃ for 8 hours.

[0053] Comparative Example 2 A high weather-resistant reflective film includes: a PET film, a reflective adhesive layer covering the surface of the PET film, and an organosilicon coating covering the surface of the adhesive layer; the reflective adhesive layer is formed by uniformly spreading glass microspheres after coating the PET film surface with adhesive material.

[0054] The adhesive material raw materials include: 100g of hydroxyl-containing acrylate resin, 8g of IPDI prepolymer, 1.5g of UV329 ultraviolet absorber, and 1g of antioxidant 1076. The mass ratio of glass microspheres to adhesive material is 1:4.

[0055] The raw materials for the silicone coating include: 8g of vinyl-terminated polydimethylsiloxane, 2g of trifluoropropylmethylcyclotrisiloxane, 3g of activated nano-silica, 2g of pentaerythritol tetra-3-mercaptopropionate, and 0.25g of 2-hydroxy-2-methylphenylacetone.

[0056] Activated nano-silica was prepared using the following steps: 15g of nano-silica was added to 80g of a 50% (w / w) aqueous ethanol solution and ultrasonically dispersed for 90min at a frequency of 65kHz. The pH of the system was adjusted to 4-5 using a 1.5mol / L acetic acid solution. 0.25g of KH570 coupling agent was added and stirred for 30min. The mixture was then refluxed at 65℃ for 3.5h, centrifuged, and the product was washed three times with deionized water and vacuum dried.

[0057] The manufacturing method of the above-mentioned high weather-resistant reflective film includes the following steps: S1. Hydroxyl-containing acrylate resin, IPDI prepolymer, UV329 ultraviolet absorber, antioxidant 1076, and 25g of ethyl acetate are mixed evenly to obtain an adhesive material. S2. Perform corona treatment on the PET film surface for 45 seconds, with a corona power of 6.5 kW / m. 2 The adhesive material is applied to the substrate surface with a thickness of 25μm and left to stand for 6 minutes. Glass microspheres are then evenly sprinkled and left to stand for 15 minutes to obtain the pretreated substrate. S3. Add vinyl-terminated polydimethylsiloxane, trifluoropropylmethylcyclotrisiloxane, activated nano-silica, pentaerythritol tetra-3-mercaptopropionate, and 2-hydroxy-2-methylphenylacetone to 100g of dichloromethane and stir until homogeneous. Spray the mixture onto the pretreated substrate surface to a thickness of 35μm. Cure under ultraviolet light for 1.2h at an ultraviolet light intensity of 450mW / cm². 2 ; rewind and mature at 65℃ for 8 hours.

[0058] The static water contact angle of the reflective films obtained in Example 5 and Comparative Examples 1-2 was measured using a contact angle tester.

[0059] The silicone coatings of two reflective films obtained in Example 5 were bonded together, pressed together with a pressure roller, and subjected to ultraviolet light (340nm, 1.5W / m). 2 The samples were irradiated for 10 minutes to obtain test samples. The peel strength of the two reflective films was determined by referring to GB / T 2792-2014 "Test Method for Peel Strength of Adhesive Tapes". The peel strength of Comparative Examples 1-2 was determined according to the aforementioned method.

[0060] like Figure 1 As shown, the reflective film obtained in Example 5 has the highest static water contact angle, which is higher than 150°, exhibiting a self-cleaning function and making it difficult for contaminants to adhere to its surface; while the reflective film obtained in Example 5 has the highest peel strength, which is significantly better than that of Comparative Example 1, but there is no significant difference from Example 5.

[0061] Reflectance A was obtained by measuring the reflectance using a spectrophotometer (Hentley, USA) in a D65 light source environment with an integrating sphere structure of d / 8°. This reflectance data was obtained by weighted averaging of reflectance in 50nm intervals within the wavelength range of 400-700nm, with the weights based on the energy distribution curve of the D65 light source.

[0062] Subsequently, an ultraviolet aging test chamber (340nm, 1.5W / m) was used. 2 The reflective films obtained in Example 5 and Comparative Examples 1-2 were subjected to simulated solar radiation for 240 hours, maintaining a temperature of 50±2℃ and a humidity of 60±2%RH. During the simulation, a 12-hour exposure and 12-hour rest cycle was maintained to simulate the alternation of day and night in a natural environment. The reflectance was then measured again to obtain reflectance B.

[0063] like Figure 2 As shown, the reflective film obtained in Example 5 has the highest reflectivity before and after simulated solar radiation, which is significantly better than the comparative example, demonstrating excellent weather resistance.

[0064] The present invention has been described in detail above. Those skilled in the art will recognize that the invention can be practiced in a wide range of ways with equivalent parameters, concentrations, and conditions without departing from its spirit and scope, and without requiring unnecessary experiments. While specific embodiments have been provided, it should be understood that further modifications can be made to the invention. In summary, according to the principles of the invention, this application is intended to include any changes, uses, or improvements to the invention, including changes made using conventional techniques known in the art that depart from the scope disclosed herein.

Claims

1. A highly weather-resistant reflective film, characterized in that, include: PET film, reflective adhesive layer covering the surface of PET film, and silicone coating covering the surface of adhesive layer; The reflective adhesive layer is formed by coating an adhesive material onto the surface of a PET film and then uniformly spreading glass microspheres. The adhesive material raw materials, by weight, include: 50-150 parts of hydroxyl-containing acrylate resin, 5-12 parts of IPDI prepolymer, 1-2 parts of UV329 ultraviolet absorber, and 0.5-1.5 parts of antioxidant 1076.

2. The high weather-resistant reflective film according to claim 1, characterized in that, The mass ratio of glass microspheres to adhesive material is 2-3:

10.

3. The high weather-resistant reflective film according to claim 1, characterized in that, The particle size of the glass microspheres is 10-50 μm.

4. The high weather-resistant reflective film according to claim 1, characterized in that, The raw materials for the organosilicon coating, by weight, include: 5-10 parts of vinyl-terminated polydimethylsiloxane, 1-3 parts of trifluoropropylmethylcyclotrisiloxane, 1-5 parts of activated nano-silica, 1-3 parts of pentaerythritol tetra-3-mercaptopropionate, and 0.1-0.4 parts of 2-hydroxy-2-methylphenylacetone.

5. The high weather-resistant reflective film according to claim 4, characterized in that, Activated nano-silica is prepared by the following steps: nano-silica is added to an ethanol aqueous solution and ultrasonically dispersed for 1-2 hours. The pH of the system is adjusted to 4-5. A silane coupling agent is added and stirred for 20-40 minutes. Perfluorooctyltrichlorosilane is added and stirred for 5-15 minutes. The mixture is refluxed at 60-70°C for 2-5 hours, centrifuged, washed with water, and vacuum dried.

6. The high weather-resistant reflective film according to claim 5, characterized in that, The mass ratio of nano-silica, silane coupling agent, and perfluorooctyltrichlorosilane is 10-20:0.1-0.4:0.1-0.

2.

7. The high weather-resistant reflective film according to claim 5, characterized in that, The ultrasonic frequency is 60-70kHz.

8. A method for manufacturing a high weather-resistant reflective film as described in any one of claims 1-7, characterized in that, Includes the following steps: S1. Hydroxyl-containing acrylate resin, IPDI prepolymer, UV329 ultraviolet absorber, antioxidant 1076, and ethyl acetate are mixed evenly to obtain an adhesive material. S2. Perform corona treatment on the PET film surface for 30-60 seconds, with a corona power of 5-8 kW / m. 2 Apply adhesive material to the surface of the corona-treated PET film, let it stand for 5-7 minutes, evenly sprinkle glass microspheres, let it stand for 10-20 minutes to obtain the pretreated base layer; S3. Add vinyl-terminated polydimethylsiloxane, trifluoropropylmethylcyclotrisiloxane, activated nano-silica, pentaerythritol tetra-3-mercaptopropionate, and 2-hydroxy-2-methylphenylacetone to dichloromethane and stir until homogeneous. Then spray the mixture onto the pretreated substrate surface and cure under ultraviolet light for 1-1.5 hours at an ultraviolet light intensity of 400-500 mW / cm². 2 Grind at 50-100℃ for 5-10 hours.

9. The method for manufacturing the high weather-resistant reflective film according to claim 8, characterized in that, In S2, the adhesive material coating thickness is 20-30μm.

10. The method for manufacturing the high weather-resistant reflective film according to claim 8, characterized in that, In S3, the coating thickness is 30-40μm.

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