A process method for improving reliability after film mounting

Abstract

The application discloses a process method for improving the reliability after film mounting, which comprises the following steps: plasma activation treatment, coating of an organic-inorganic hybrid transition layer, application of a pressure-releasable pressure-sensitive adhesive composition and optical base film lamination, roller rolling, second curing, low-temperature pressure release treatment and the like. The application improves the reliability of the film layer, is especially suitable for the fields of vehicle-mounted display screens, building glass explosion-proof films and electronic equipment screen protection films and the like, and can effectively improve the safety and service life of products.

Description

Technical Field

[0001] This invention relates to the field of film sealing technology, and in particular to a process method for improving the reliability of film installation. Background Technology

[0002] With the advancement of technology and the increasing demand from applications in consumer electronics, architectural glass, and other fields, the functional and reliability requirements for membrane materials are also rising. Especially in areas such as automotive displays, safety films for architectural glass, and screen protectors for electronic devices, the film layer must not only possess excellent optical properties but also meet high-strength physical performance requirements, such as scratch resistance, UV resistance, and good adhesion. However, traditional membrane materials often suffer from problems such as weak adhesion, easy film peeling, and poor durability, which directly affect the product's lifespan and safety.

[0003] Past technologies have focused on improving the optical properties or surface hardness of membrane materials, but have often neglected the adhesion between the membrane and the substrate and the stability of the membrane during long-term use.

[0004] Therefore, developing a new process that can effectively improve the adhesion between the membrane and the substrate and increase the durability of the membrane is key to improving the reliability of membrane materials.

[0005] Therefore, this invention is proposed. Summary of the Invention

[0006] To address the aforementioned technical problems, this application provides a process method that can significantly improve the reliability of film installation, solving problems such as easy film peeling, insufficient adhesion, and poor durability in existing film application technologies.

[0007] In order to achieve the objective of this invention, the following technical solution is adopted: This application provides a process method to improve the reliability of film installation, including the following steps: S1. After plasma activation treatment of the surface to be treated, an organic-inorganic hybrid transition layer solution is coated on the surface to be treated, and a transition layer is formed by first curing. S2. Coat the surface of the transition layer with a pressure-relief pressure-sensitive adhesive composition to form a pressure-sensitive adhesive layer; S3. The optical base film is pressed onto the pressure-sensitive adhesive layer, and after being rolled by a pressure roller, it undergoes a second curing process. The finished product after pressing is then placed in a gradient cooling environment for low-temperature pressure release and post-curing to complete the film preparation. The organic-inorganic hybrid transition layer solution comprises a hyperbranched polysiloxane-epoxy resin composite and a nano-titanium dioxide-graphene oxide composite sheet material, wherein the mass ratio of the hyperbranched polysiloxane-epoxy resin composite to the nano-titanium dioxide-graphene oxide composite sheet material is 1:(0.3-0.8). The pressure-relief adhesive composition comprises a fluorinated acrylate copolymer, thermoresponsive polymer microspheres, and a Schiff base metal complex, wherein the mass ratio of the fluorinated acrylate copolymer to the thermoresponsive polymer microspheres is 1:(0.1-0.4).

[0008] Furthermore, the hyperbranched polysiloxane-epoxy resin composite is prepared by an addition reaction between an amino-terminated hyperbranched polysiloxane and a dicyclopentadiene phenol epoxy resin, wherein the degree of branching of the amino-terminated hyperbranched polysiloxane is 0.4-0.6 and the molecular weight is 2000-4000 Da.

[0009] Furthermore, the nano-titanium dioxide-graphene oxide composite sheet material has a sheet thickness of 5nm-20nm, a sheet diameter of 0.5μm-2μm, and a specific surface area of ​​150m². 2 / g-300m 2 / g; In the nano-titanium dioxide-graphene oxide composite sheet material, titanium dioxide nanoparticles are grown in situ on the surface of graphene oxide sheets, and the mass ratio of titanium dioxide to graphene oxide is 1:(0.5-1.5).

[0010] Furthermore, the organic-inorganic hybrid transition layer solution also contains imidazole compounds and acetylacetone metal complexes, wherein the imidazole compounds are one or more of 2-methylimidazole, 2-ethyl-4-methylimidazole or 1-cyanoethyl-2-ethyl-4-methylimidazole, and the acetylacetone metal complexes are aluminum acetylacetone or zirconium acetylacetone.

[0011] Furthermore, the fluorinated acrylate copolymer is copolymerized from the following monomers in parts by mass: 35-50 parts of isooctyl acrylate, 15-25 parts of butyl acrylate, 5-15 parts of hexafluorobutyl methacrylate, 3-8 parts of acrylmorpholine, and 2-5 parts of itaconic acid monobutyl ester.

[0012] Furthermore, the thermoresponsive polymer microspheres are prepared by soap-free emulsion polymerization of N-isopropylacrylamide and glycidyl methacrylate, wherein the molar ratio of glycidyl methacrylate to N-isopropylacrylamide is 1:(5-10).

[0013] Furthermore, the Schiff base metal complex is a zinc salicylaldehyde imide complex or a copper salicylaldehyde imide complex.

[0014] Furthermore, the second curing process employs segmented temperature-increasing curing, first curing at 40℃-50℃ for 12h-24h, and then increasing the temperature to 60℃-70℃ for another 12h-24h.

[0015] Furthermore, the gradient cooling environment is a three-stage cooling program: the first stage cools from room temperature to 0℃-5℃ at a cooling rate of 5℃ / h-8℃ / h, and holds for 2h-4h; the second stage cools to -10℃ to -15℃ at a cooling rate of 3℃ / h-5℃ / h, and holds for 4h-6h; the third stage cools to -20℃ to -25℃ at a cooling rate of 2℃ / h-3℃ / h, and holds for 6h-10h for low-temperature decompression treatment.

[0016] The present invention also provides an application of the above-mentioned process method for improving the reliability of film installation in the preparation of explosion-proof film for vehicle display screens, safety explosion-proof film for architectural glass, or protective film for electronic device screens.

[0017] The present invention has the following technical effects: (1) This application can significantly improve the adhesion between the film layer and the substrate by performing plasma activation treatment on the substrate surface and coating an organic-inorganic hybrid transition layer containing hyperbranched polysiloxane-epoxy resin composite and nano titanium dioxide-graphene oxide composite sheet material.

[0018] (2) The pressure-sensitive adhesive composition used in this application consists of a fluorinated acrylate copolymer, thermoresponsive polymer microspheres, and a Schiff base metal complex, enabling controlled pressure release and stress regulation during the bonding process. The thermoresponsive microspheres can change the flexibility of the adhesive layer under temperature changes, reducing internal stress accumulation and preventing blistering or deformation of the film layer, while the Schiff base metal complex and the fluorinated acrylate copolymer provide excellent adhesion and chemical resistance. This combination significantly improves the long-term stability of the film layer, enabling the film to maintain a firm and uniform bonding effect even in complex usage environments. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0020] In a first aspect, the present invention provides a process method for improving the reliability of film installation, comprising the following steps: S1. After plasma activation treatment of the surface to be treated, an organic-inorganic hybrid transition layer solution is coated on the surface to be treated, and a transition layer is formed by first curing. S2. Coat the surface of the transition layer with a pressure-relief pressure-sensitive adhesive composition to form a pressure-sensitive adhesive layer; S3. The optical base film is pressed onto the pressure-sensitive adhesive layer, and after being rolled by a pressure roller, it undergoes a second curing process. The finished product after pressing is then placed in a gradient cooling environment for low-temperature pressure release and post-curing to complete the film preparation. The organic-inorganic hybrid transition layer solution comprises a hyperbranched polysiloxane-epoxy resin composite and a nano-titanium dioxide-graphene oxide composite sheet material, wherein the mass ratio of the hyperbranched polysiloxane-epoxy resin composite to the nano-titanium dioxide-graphene oxide composite sheet material is 1:(0.3-0.8). The pressure-relief adhesive composition comprises a fluorinated acrylate copolymer, thermoresponsive polymer microspheres, and a Schiff base metal complex, wherein the mass ratio of the fluorinated acrylate copolymer to the thermoresponsive polymer microspheres is 1:(0.1-0.4).

[0021] The process method provided in this application significantly improves the adhesion, durability, and stability of the film layer. First, plasma activation is used to pretreat the surface to increase the energy of the substrate surface, improving the adhesion between the film layer and the substrate, and laying the foundation for subsequent film bonding. This treatment allows for the formation of a more uniform interface with good affinity, thus contributing to improved long-term film stability. Next, an organic-inorganic hybrid transition layer solution is coated onto the activated surface. This transition layer consists of a hyperbranched polysiloxane-epoxy resin composite and nano-titanium dioxide-graphene oxide composite sheet material. The special structure of the hyperbranched polysiloxane-epoxy resin composite enables it to form strong chemical bonds with the substrate surface. The transition layer formed after the first curing step provides a strong adhesive foundation for the subsequent pressure-sensitive adhesive layer, ensuring the long-term stability of the film layer.

[0022] Building upon this, the second step involves coating the transition layer surface with a pressure-sensitive adhesive composition that combines a fluorinated acrylate copolymer with thermoresponsive polymer microspheres. The fluorinated acrylate copolymer enhances the film's chemical resistance and UV resistance, while the thermoresponsive polymer microspheres provide good flexibility and temperature control under varying temperatures. This design ensures that the film maintains excellent adhesion and weather resistance even in environments with significant temperature fluctuations. Furthermore, the addition of Schiff base metal complexes further improves the adhesive's anti-aging properties and extends the film's lifespan.

[0023] After the optical base film is laminated onto the pressure-sensitive adhesive layer and rolled with pressure rollers, a second curing process firmly bonds the various components of the film layer together, forming a uniform and stable structure. At this point, the film layer possesses extremely high adhesion and strong durability, maintaining stable performance under different temperature and humidity environments. To further ensure the stability of the film layer, this application also employs a gradient cooling low-temperature pressure relief treatment method. By gradually cooling in stages, any stress that may exist within the film layer is released, preventing deformation or decreased adhesion due to excessively rapid temperature changes. This process ensures that the film layer does not experience defects such as edge lifting or blistering even after prolonged use.

[0024] In some embodiments, the hyperbranched polysiloxane-epoxy resin composite is prepared by an addition reaction between an amino-terminated hyperbranched polysiloxane and a dicyclopentadiene phenol epoxy resin, wherein the degree of branching of the amino-terminated hyperbranched polysiloxane is 0.4-0.6 and the molecular weight is 2000-4000 Da.

[0025] In some embodiments, the nano-titanium dioxide-graphene oxide composite sheet material has a sheet thickness of 5nm-20nm, a sheet diameter of 0.5μm-2μm, and a specific surface area of ​​150m². 2 / g-300m 2 / g; In the nano-titanium dioxide-graphene oxide composite sheet material, titanium dioxide nanoparticles are grown in situ on the surface of graphene oxide sheets, and the mass ratio of titanium dioxide to graphene oxide is 1:(0.5-1.5).

[0026] In some embodiments, the organic-inorganic hybrid transition layer solution further comprises an imidazole compound and an acetylacetone metal complex, wherein the imidazole compound is one or more of 2-methylimidazole, 2-ethyl-4-methylimidazole or 1-cyanoethyl-2-ethyl-4-methylimidazole, and the acetylacetone metal complex is aluminum acetylacetone or zirconium acetylacetone.

[0027] In some embodiments, the fluorinated acrylate copolymer is copolymerized from the following monomers in parts by weight: 35-50 parts isooctyl acrylate, 15-25 parts butyl acrylate, 5-15 parts hexafluorobutyl methacrylate, 3-8 parts acrylmorpholine, and 2-5 parts itaconic acid monobutyl ester.

[0028] In some embodiments, the thermoresponsive polymer microspheres are prepared by soap-free emulsion polymerization of N-isopropylacrylamide and glycidyl methacrylate, wherein the molar ratio of glycidyl methacrylate to N-isopropylacrylamide is 1:(5-10).

[0029] This application introduces thermoresponsive polymer microspheres into a pressure-sensitive adhesive composition, significantly improving the stress regulation capability and long-term stability of the film layer, while also enhancing its adhesion under different environments. These thermoresponsive polymer microspheres can change their flexibility and morphology according to temperature changes, thereby achieving automatic adjustment of internal stress during film installation and use. When the film layer is subjected to temperature fluctuations or external forces, the microspheres can locally deform or expand, absorbing and dispersing the stress generated within the film layer, preventing stress concentration that could lead to blistering, edge lifting, or localized detachment. This ensures that the film layer maintains uniform adhesion and a smooth surface even under high or low temperature environments. The addition of thermoresponsive microspheres, combined with the use of fluorinated acrylate copolymers and Schiff base metal complexes, gives the pressure-sensitive adhesive layer both excellent adhesion and outstanding weather resistance and chemical stability, making it less prone to aging or deterioration during long-term use.

[0030] During installation, these microspheres can adjust the softness of the adhesive layer, ensuring uniform adhesion of the film to the substrate surface during pressing and rolling. Even with slight unevenness or bending of the substrate, they effectively reduce the generation of air bubbles and localized non-adhesion. Simultaneously, the thermally responsive properties of the microspheres allow the film to maintain stable adhesion under varying ambient temperatures, preventing localized detachment or loosening due to seasonal temperature changes. This is particularly important for applications requiring high film stability, such as automotive displays, architectural glass, and screen protectors for electronic devices. Furthermore, the uniform distribution and size control of the microspheres within the adhesive layer effectively prevent uneven thickness distribution, further guaranteeing the overall flatness and appearance quality of the film.

[0031] By introducing thermoresponsive polymer microspheres, the pressure-sensitive adhesive composition not only improves the controllability and efficiency of installation during the construction phase, but also significantly enhances the reliability and durability of the membrane during use. This technology can significantly reduce the risk of membrane damage caused by temperature changes, stress accumulation, or external impacts, improve the safety and service life of the membrane in long-term use, while maintaining the optical transparency and aesthetics of the membrane.

[0032] In some embodiments, the Schiff base metal complex is a zinc salicylaldehyde imide complex or a copper salicylaldehyde imide complex.

[0033] In some embodiments, the second curing is carried out by staged temperature increase curing, first curing at 40℃-50℃ for 12h-24h, and then increasing the temperature to 60℃-70℃ for 12h-24h.

[0034] In some embodiments, the gradient cooling environment is a three-stage cooling program: the first stage cools from room temperature to 0℃-5℃ at a cooling rate of 5℃ / h-8℃ / h and is maintained for 2h-4h; the second stage cools to -10℃ to -15℃ at a cooling rate of 3℃ / h-5℃ / h and is maintained for 4h-6h; the third stage cools to -20℃ to -25℃ at a cooling rate of 2℃ / h-3℃ / h and is maintained for 6h-10h for low-temperature decompression treatment.

[0035] Secondly, this application also provides the application of the above-mentioned process method for improving the reliability of film installation in the preparation of explosion-proof film for vehicle display screens, safety explosion-proof film for architectural glass, or protective film for electronic device screens.

[0036] The following is a detailed explanation using specific embodiments: Example 1: S1, Preparation of the transition layer Step 1.1: Synthesis of hyperbranched polysiloxane-epoxy resin composite Under nitrogen protection, 200g of terminal amino hyperbranched polysiloxane (purchased from Shandong Silicon Science New Materials Co., Ltd.) with a molecular weight of 2000 Da and a branching degree of 0.4 and 240g of dicyclopentadiene phenol epoxy resin (purchased from Shengquan Group, epoxy equivalent 256 g / eq) with a molecular weight of 2000 Da and a branching degree of 0.4 were added to a 2L four-necked flask equipped with a stirrer, thermometer and dropping funnel.

[0037] The molar ratio of the controlled-end amino hyperbranched polysiloxane to epoxy resin was 1:1.2. The reaction was carried out in a constant temperature water bath at 80℃ with mechanical stirring for 3 hours at a speed of 300 rpm to obtain the hyperbranched polysiloxane-epoxy resin composite for later use.

[0038] Step 1.2: Preparation of nano-titanium dioxide-graphene oxide composite sheet material The graphene oxide was prepared by in-situ growth method: 100g of graphene oxide (1μm in diameter, purchased from Changzhou Sixth Element) was dispersed in anhydrous ethanol, 150g of tetrabutyl titanate was added, and a small amount of deionized water was slowly added dropwise under ice-water bath conditions to control the mass ratio of titanium dioxide to graphene oxide to be 1:0.67.

[0039] The pH was adjusted to 3-4, and the hydrolysis reaction was carried out at 40℃ for 6 hours to allow titanium dioxide nanoparticles to grow in situ on the surface of graphene oxide sheets.

[0040] After the reaction was completed, the material was centrifuged and washed, dried under vacuum at 60℃ for 12 hours, and then calcined at 450℃ in a nitrogen atmosphere for 2 hours to obtain nano-titanium dioxide-graphene oxide composite sheet material for later use.

[0041] Step 1.3: Preparation of the transition layer solution Take 100g of the hyperbranched polysiloxane-epoxy resin composite obtained in step 1.1, add 50g of the nano-titanium dioxide-graphene oxide composite sheet material obtained in step 1.2 (i.e., mass ratio 1:0.5), and simultaneously add 2g of 2-methylimidazole (purchased from Shanghai Aladdin Biochemical Technology Co., Ltd.) and 1g of aluminum acetylacetonate (purchased from Maclean) as curing accelerators. Dilute with ethyl acetate to a solid content of 40%, disperse in a high-speed disperser at 1500rpm for 30min, and then ultrasonically degas for 20min to obtain a uniform organic-inorganic hybrid transition layer solution.

[0042] Step 1.4: Coating and First Curing A clean glass substrate was selected as the surface to be treated, and the glass surface was activated using an atmospheric pressure plasma treatment device with a power of 800W and a linear speed of 5m / min. After treatment, the transition layer solution was uniformly coated onto the glass surface by spin coating. The spin coating parameters were: low speed 500 rpm for 10 s, high speed 2000 rpm for 30 s. After coating, the substrate is placed horizontally in a clean oven for the first curing. The specific curing procedure is as follows: the temperature is increased from room temperature to 80°C at a rate of 2°C / min, and held at this temperature for 30 min to allow the solvent to fully evaporate and initially crosslink; then the temperature is increased to 120°C at a rate of 1°C / min, and held for 60 min to allow the epoxy groups and amino groups to undergo a deep crosslinking reaction; finally, it is naturally cooled to room temperature to obtain a transparent transition layer with a thickness of about 8 μm.

[0043] S2. Preparation of pressure-sensitive adhesive layer Step 2.1: Synthesis of fluorinated acrylate copolymers By mass fraction, 35g of isooctyl acrylate, 15g of butyl acrylate, 5g of hexafluorobutyl methacrylate, 3g of acrylmorpholine and 2g of itaconic acid monobutyl ester were mixed evenly, 100ml of ethyl acetate and 0.3g of initiator AIBN were added, and the polymerization reaction was carried out in a water bath at 75℃ for 8h under nitrogen protection and the rotation speed was 250rpm to obtain a fluorinated acrylate copolymer solution.

[0044] Step 2.2: Preparation of thermoresponsive polymer microspheres By using a soap-free emulsion polymerization method, 20g of N-isopropylacrylamide and glycidyl methacrylate were added to a reactor at a molar ratio of 8:1, along with 500ml of deionized water. Using 0.2g of potassium persulfate as an initiator, the reaction was carried out at 70℃ for 6 hours with a stirring speed of 400rpm, yielding a thermoresponsive polymer microsphere emulsion with an average particle size of 200nm. The emulsion was freeze-dried (-50℃, 24 hours) to obtain a white powder for later use.

[0045] Step 2.3: Formulation of the pressure-sensitive adhesive composition Take 100g of the fluorinated acrylate copolymer solution obtained in step 2.1, add 25g of the thermoresponsive polymer microspheres obtained in step 2.2 (i.e., mass ratio 1:0.25), add 5g of salicylaldehyde imine zinc complex (purchased from Shanghai Dibai Biotechnology Co., Ltd.), add ethyl acetate to adjust the viscosity to about 1500mPa·s, stir at 500rpm for 2h on a magnetic stirrer, and then sonicate to degas for 15min to obtain a pressure-sensitive adhesive composition that can release pressure.

[0046] S3. Film lamination and post-processing The pressure-sensitive adhesive composition described above is applied to the surface of the transition layer obtained in step S1 using a blade coating method. The wet film thickness is controlled to be 40 μm. The solvent is removed by drying in an oven at 60°C for 5 min, forming a pressure-sensitive adhesive layer with a thickness of approximately 20 μm.

[0047] Then carefully cover the base film onto the pressure-sensitive adhesive layer.

[0048] Roller pressing: Rubber rollers are used to press and bond the product at a speed of 2m / min and a linear pressure of 0.4MPa, rolling back and forth twice to ensure complete bonding without air bubbles.

[0049] Second curing: The bonded sample is placed horizontally in a precision oven for staged temperature-increase curing. First stage: Curing at a constant temperature of 45℃ for 18 hours. This stage mainly promotes the slow reaction of the low reactive groups inside the pressure-sensitive adhesive. Second stage: Increase the temperature to 65℃ at a rate of 0.5℃ / min, and continue to cure at this temperature for 18 hours to achieve deep cross-linking of the pressure-sensitive adhesive system.

[0050] Low-temperature pressure release and post-curing: After lamination, the finished product is transferred to a programmable high and low temperature alternating test chamber for gradient cooling treatment. The first step: The temperature is uniformly reduced from room temperature (25℃) to 3℃ at a rate of 6℃ / h, and maintained at this temperature for 3h to allow the internal stress of the system to be initially released. The second stage: the temperature was uniformly reduced to -12℃ at a cooling rate of 4℃ / h and held for 5h to promote the phase change of the thermally responsive microspheres and absorb interfacial stress. The third stage: The temperature was uniformly reduced to -22℃ at a cooling rate of 2.5℃ / h and held for 8 hours to allow the Schiff alkali metal complex to form dynamic coordination bond recombination at low temperature.

[0051] After the treatment is completed, the film is slowly restored to room temperature at a rate of 2℃ / h to obtain a high-reliability film.

[0052] Comparative Example 1 D1. Substrate Treatment Step D1.1: Substrate Cleaning A glass substrate of the same specifications as in the example was selected as the surface to be treated, and was ultrasonically cleaned with acetone, ethanol and deionized water for 15 minutes each, and then dried with nitrogen.

[0053] Step D1.2: Primer treatment A commercially available silane coupling agent primer (purchased from Dow Corning, with γ-glycidyl etheroxypropyltrimethoxysilane as the main component) was diluted with anhydrous ethanol to a solid content of 2%. It was then uniformly coated onto the glass surface using a spin coating method. The spin coating parameters were: low speed 500 rpm for 10 seconds, and high speed 2000 rpm for 30 seconds. After coating, the primer was dried in an oven at 80°C for 10 minutes to form the base coating layer.

[0054] D2. Preparation of pressure-sensitive adhesive layer Step D2.1: Synthesis of conventional acrylic pressure-sensitive adhesive By mass, 50g of isooctyl acrylate, 30g of butyl acrylate, and 2g of acrylic acid were mixed evenly, and 100ml of ethyl acetate and 0.3g of initiator AIBN were added. The mixture was polymerized in a water bath at 75℃ for 8 hours under nitrogen protection and the rotation speed was 250rpm to obtain a conventional acrylic pressure-sensitive adhesive solution with a solid content of 45.0%.

[0055] Step D2.2: Formulation of pressure-sensitive adhesive composition Take 100g of the conventional acrylic pressure-sensitive adhesive solution obtained in step D2.1, add ethyl acetate to adjust the viscosity to about 1500mPa·s, stir at 500rpm for 1h on a magnetic stirrer, and then sonicate to degas for 15min to obtain the pressure-sensitive adhesive composition.

[0056] D3. Film lamination and post-processing The pressure-sensitive adhesive composition described above was applied to the surface of the base layer obtained in step D1 using a blade coating method. The wet film thickness was controlled to be 50 μm. The solvent was removed by drying in an oven at 60°C for 5 min, forming a pressure-sensitive adhesive layer with a thickness of approximately 25 μm.

[0057] Then carefully cover the base film onto the pressure-sensitive adhesive layer.

[0058] Roller pressing: Rubber rollers are used to press and bond the product at a speed of 0.5m / min and a linear pressure of 0.3MPa, rolling back and forth 3 times to ensure complete bonding without air bubbles.

[0059] Curing treatment: Place the bonded sample horizontally in a constant temperature oven and allow it to cure at room temperature (25℃) for 7 days to allow the pressure-sensitive adhesive system to naturally cross-link and cure. After the treatment, a regular film is obtained.

[0060] Experimental Example: Performance Evaluation of Explosion-proof Film for Vehicle Display Screens in Practical Applications I. Experimental Objective This experimental example aims to simulate a real-world application environment. The films prepared in Example 1 and Comparative Example 1 are applied between the cover glass of the vehicle display screen and the display module. Through a series of standardized performance tests, their reliability under complex working conditions is evaluated.

[0061] II. Sample Preparation Substrate preparation: Cover glass: Chemically strengthened aluminosilicate glass that meets automotive standards.

[0062] Display module simulation: To simplify testing and focus on adhesive layer performance, a polarizer of the same size is bonded to another piece of transparent glass, or a black acrylic sheet with a coefficient of thermal expansion similar to that of glass is used to simulate the display module.

[0063] Sample preparation: Following the complete steps of Example 1 and Comparative Example 1, the film was prepared on the cover glass.

[0064] Then, the prepared cover glass (with film) is bonded to the display module simulation piece in the final step of bonding and post-processing (roller pressing, second curing, and low-temperature pressure release treatment) to obtain a complete three-layer structure test sample. Example / Comparative Example: 10 samples were prepared, 5 for initial performance testing and 5 for performance testing after environmental aging.

[0065] III. Performance Testing Items and Methods 1. Initial optical performance test (average value of 5 samples) Test items: transmittance, haze, and yellowing index.

[0066] Testing process: Baseline calibration was performed on blank cover glass under an environment of room temperature (25℃±2℃) and humidity of 50%±5%.

[0067] Place the prepared test sample (cover plate-film-module) in the instrument's optical path.

[0068] The transmittance, haze value, and yellowing index (YI) of the samples in the visible light band of 380nm-780nm were measured and recorded respectively.

[0069] 2. Bond strength and reliability test (average value of 5 samples) Test item: 180° peel strength (initial and after boiling / high temperature and high humidity).

[0070] Testing process: Initial peel strength: The module layer in the sample is fixed in the lower fixture of the testing machine, and the cover glass layer is peeled upward in a 180° direction.

[0071] Peel at a stretching speed of 300 mm / min, record the peeling force (N / 25 mm), and take the average value of the effective peeled segment.

[0072] Peel strength after damp heat aging: Five more samples were placed in a constant temperature and humidity test chamber, with the temperature set at 85℃ and the humidity at 85%RH, for 1000 hours.

[0073] After removal, allow to recover at room temperature for 2 hours, then test the 180° peel strength using the method described above.

[0074] Boiling water resistance test: The sample was completely immersed in a constant temperature water bath at 65°C (simulating extreme exposure to sunlight or hot water splashing) for 24 hours.

[0075] After removing the product, pat the surface dry with a paper towel and allow it to return to room temperature for 2 hours. Then test the 180° peel strength and observe whether the adhesive layer turns white or peels off.

[0076] 3. Environmental simulation and durability testing (average value of 5 samples) Test items: appearance and bubble condition after high temperature and high humidity cycling and thermal shock tests.

[0077] Testing process: High temperature and high humidity storage: The sample was placed in a test chamber at 85℃ / 85%RH for 1000 hours.

[0078] Take out the sample every 240 hours and observe it under standard conditions for any bubbles, white edges, delamination, yellowing, or other phenomena on the surface and edges, and take photos to record the results.

[0079] Thermal shock test: Place the sample in a thermal shock test chamber and perform the following cycle: -40℃ for 30 minutes → 85℃ for 30 minutes, with a transition time of less than 15 seconds.

[0080] Remove after 500 cycles.

[0081] After restoring for 2 hours under standard conditions, observe the interior and edges of the adhesive layer with a high-power microscope (50-100x) to see if there are microcracks, enlarged bubbles, or new bubbles. Test its transmittance and haze again and compare them with the initial values.

[0082] The final test results are shown in Table 1 below.

[0083] Table 1. Initial optical performance, bond strength and reliability test results Table 2 Results of Environmental Simulation and Durability Tests Based on a comprehensive evaluation of the experimental data, the method of this application demonstrates significant advantages. In terms of optical performance, Example 1 exhibits a transmittance of 92.3%, haze controlled below 0.9%, and a yellowing index below 1.2, significantly superior to Comparative Example 1's 90.5% transmittance, 1.5% haze, and yellowing index of 2.8. This fully demonstrates the good compatibility between the hyperbranched polysiloxane-epoxy resin transition layer and the fluorinated acrylate pressure-sensitive adhesive, effectively avoiding the light scattering problems caused by traditional physical blending. Regarding adhesive strength, the initial peel strength of Example 1 remained between 18.5 N / 25 mm, and after aging at 85°C / 85%RH for 1000 hours, it still maintained a strength of over 16.8 N / 25 mm. In contrast, the peel strength of Comparative Example 1 dropped sharply from 12.3 N / 25 mm to 4.2 N / 25 mm, and after boiling in water at 65°C for 24 hours, it showed large-area blistering and detachment. This fully verifies the chemical anchoring effect formed between the terminal amino hyperbranched polysiloxane in the transition layer and the glass surface.

[0084] The most critical thermal shock test results showed that after 500 cycles of extreme temperatures ranging from -40°C to 85°C, no bubbles, delamination, or microcracks appeared in Example 1, and the haze change rate only increased slightly. In contrast, Comparative Example 1 showed severe delamination and adhesive layer cracking, with haze soaring by 3.5%. This is attributed to the absorption of interfacial stress by the thermally responsive polymer microspheres during the low-temperature phase transition, while the Schiff alkali metal complex dissipated energy through dynamic coordination bond recombination, effectively preventing the generation and propagation of microcracks.

[0085] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the technical solutions of the embodiments of the present invention.

Claims

1. A process method for improving the reliability of film installation, characterized in that, Includes the following steps: S1. After plasma activation treatment of the surface to be treated, an organic-inorganic hybrid transition layer solution is coated on the surface to be treated, and a transition layer is formed by first curing. S2. Coat the surface of the transition layer with a pressure-relief pressure-sensitive adhesive composition to form a pressure-sensitive adhesive layer; S3. The optical base film is pressed onto the pressure-sensitive adhesive layer, and after being rolled by a pressure roller, it undergoes a second curing process. The finished product after pressing is then placed in a gradient cooling environment for low-temperature pressure release and post-curing to complete the film preparation. The organic-inorganic hybrid transition layer solution comprises a hyperbranched polysiloxane-epoxy resin composite and a nano-titanium dioxide-graphene oxide composite sheet material, wherein the mass ratio of the hyperbranched polysiloxane-epoxy resin composite to the nano-titanium dioxide-graphene oxide composite sheet material is 1:(0.3-0.8). The pressure-relief adhesive composition comprises a fluorinated acrylate copolymer, thermoresponsive polymer microspheres, and a Schiff base metal complex, wherein the mass ratio of the fluorinated acrylate copolymer to the thermoresponsive polymer microspheres is 1:(0.1-0.4).

2. The process method for improving the reliability of film installation according to claim 1, characterized in that, The hyperbranched polysiloxane-epoxy resin composite is prepared by an addition reaction between an amino-terminated hyperbranched polysiloxane and a dicyclopentadiene phenol epoxy resin. The amino-terminated hyperbranched polysiloxane has a branching degree of 0.4-0.6 and a molecular weight of 2000-4000 Da.

3. The process method for improving the reliability of film installation according to claim 1, characterized in that, The nano-titanium dioxide-graphene oxide composite sheet material has a sheet thickness of 5nm-20nm, a sheet diameter of 0.5μm-2μm, and a specific surface area of ​​150m². 2 / g-300m 2 / g; In the nano-titanium dioxide-graphene oxide composite sheet material, titanium dioxide nanoparticles are grown in situ on the surface of graphene oxide sheets, and the mass ratio of titanium dioxide to graphene oxide is 1:(0.5-1.5).

4. The process method for improving the reliability of film installation according to claim 1, characterized in that, The organic-inorganic hybrid transition layer solution also contains imidazole compounds and acetylacetone metal complexes. The imidazole compounds are one or more of 2-methylimidazole, 2-ethyl-4-methylimidazole, or 1-cyanoethyl-2-ethyl-4-methylimidazole, and the acetylacetone metal complexes are aluminum acetylacetone or zirconium acetylacetone.

5. The process method for improving the reliability of film installation according to claim 1, characterized in that, The fluorinated acrylate copolymer is copolymerized from the following monomers in parts by mass: 35-50 parts of isooctyl acrylate, 15-25 parts of butyl acrylate, 5-15 parts of hexafluorobutyl methacrylate, 3-8 parts of acrylmorpholine, and 2-5 parts of itaconic acid monobutyl ester.

6. The process method for improving the reliability of film installation according to claim 1, characterized in that, The thermoresponsive polymer microspheres are prepared by soap-free emulsion polymerization of N-isopropylacrylamide and glycidyl methacrylate, wherein the molar ratio of glycidyl methacrylate to N-isopropylacrylamide is 1:(5-10).

7. The process method for improving the reliability of film installation according to claim 1, characterized in that, The Schiff base metal complex is a zinc salicylaldehyde imide complex or a copper salicylaldehyde imide complex.

8. The process method for improving the reliability of film installation according to claim 1, characterized in that, The second curing process employs a segmented temperature increase curing method, first curing at 40℃-50℃ for 12h-24h, and then increasing the temperature to 60℃-70℃ for another 12h-24h.

9. The process method for improving the reliability of film installation according to claim 1, characterized in that, The gradient cooling environment consists of a three-stage cooling program: the first stage cools the room temperature to 0℃-5℃ at a rate of 5℃ / h-8℃ / h and holds for 2h-4h; the second stage cools the room temperature to -10℃ to -15℃ at a rate of 3℃ / h-5℃ / h and holds for 4h-6h; and the third stage cools the room temperature to -20℃ to -25℃ at a rate of 2℃ / h-3℃ / h and holds for 6h-10h for low-temperature decompression treatment.

10. The application of a process method for improving the reliability of film installation as described in any one of claims 1-9 in the preparation of explosion-proof films for vehicle displays, safety explosion-proof films for architectural glass, or protective films for electronic device screens.

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