Weight-reducing car window strengthening coating and construction process thereof

Abstract

The invention discloses a weight-reducing car window strengthening coating and a construction process thereof, the weight-reducing car window strengthening coating comprises a base material and functional additives, the base material is bisphenol A epoxy resin and an anhydride curing agent, the functional additives comprise surface modified nano SiO2, a UV photoinitiator, microcapsules and a dispersion system, and the dispersion system is dimethyl nylon acid and a combined solvent. According to the present invention, by introducing a variety of functional materials, the synergistic enhancement of the wear resistance, the electric conduction, the self-repairing and other performances of the coating is achieved, and the different types of the nanometer materials cooperate with each other to provide the respective advantages so as to significantly improve the comprehensive performance of the coating.

Description

Technical Field

[0001] The present invention relates to the technical field of polymer material surface treatment, and in particular to a weight-reducing vehicle window strengthening coating and a construction process thereof. Background Art

[0002] With the rapid development of modern industrial technology, especially in high-tech fields such as aerospace, rail transportation, and new energy vehicles, extremely stringent requirements have been placed on material performance. Traditional soda-lime glass is heavy and fragile, and it is difficult to meet the high-performance material requirements of these fields. Polycarbonate (PC) board has become an ideal choice to replace traditional glass due to its advantages such as light weight, high strength, impact resistance and excellent processing performance. However, the preparation of a strengthening coating on the surface of the PC board with excellent wear resistance, weather resistance, impact resistance and multifunctional properties (such as electromagnetic shielding, self-repair, etc.) is still a technical problem that needs to be overcome.

[0003] Existing coating processes have numerous drawbacks. For example, some fail to properly address adhesion issues between the coating and the PC substrate, resulting in easy coating detachment. While some coatings offer some functionality, they lack weather resistance and long-term stability. Furthermore, some coating processes have stringent environmental requirements during application, increasing production costs and complexity. Therefore, developing a novel, lightweight, enhanced coating process for automotive windows holds significant practical significance and holds broad market potential. Summary of the Invention

[0004] The purpose of the present invention is to provide a weight-reducing window strengthening coating and its construction process. By introducing a variety of functional materials, the coating achieves synergistic enhancement in various properties such as wear resistance, conductivity, and self-repair. Different types of nanomaterials cooperate with each other, exerting their respective advantages, and significantly improving the overall performance of the coating.

[0005] The above technical objectives of the present invention are achieved through the following technical solutions:

[0006] A weight-reducing vehicle window strengthening coating, characterized in that it includes a base material and functional additives, wherein the base material is bisphenol A epoxy resin and an anhydride curing agent, and the functional additives include surface-modified nano-SiO2, a UV photoinitiator, microcapsules and a dispersion system, and the dispersion system is dimethyl nylonate and a combined solvent. The mass fractions of the above components in the coating are as follows: bisphenol A epoxy resin accounts for 50-60wt%, the anhydride curing agent accounts for 12-20wt%, the surface-modified nano-SiO2 accounts for 1.5-3wt%, the UV photoinitiator accounts for 2-4wt%, the silver-coated copper nanowires account for 1.5-3wt%, the microcapsules account for 3-5wt%, the dimethyl nylonate accounts for 10-15wt%, and the butanone accounts for 8-10wt%.

[0007] Preferably, the bisphenol A epoxy resin is E-51 epoxy resin, and the epoxy value is 0.51 to 0.54 mol / g.

[0008] Preferably, the acid anhydride curing agent is methyltetrahydrophthalic anhydride.

[0009] Preferably, the surface-modified nano-SiO2 is nano-SiO2 surface-treated with silane coupling agent KH-570, with a surface grafting rate of 85-92% and a particle size of 20 nm.

[0010] Preferably, the UV photoinitiator is TPO-L.

[0011] Preferably, the thickness of the outer silver layer of the silver-clad copper nanowire is 5 to 8 nm, the thickness of the inner copper layer is 10 to 15 nm, and the aspect ratio is greater than 1000.

[0012] Preferably, the particle size of the microcapsules is 5 to 10 nm, the coverage rate is not less than 95%, the capsule material of the microcapsules is selected from one of gelatin, gum arabic, polyvinyl alcohol or polylactic acid, the core material of the microcapsules includes 82wt% of bisphenol A epoxy resin, 8wt% of a curing agent and 10wt% of a diluent, the curing agent is selected from one of polyamide, amine compounds or acid anhydride compounds, and the diluent is selected from one of acetone or toluene.

[0013] A construction process for a weight-reducing vehicle window strengthening coating, characterized by comprising the following steps:

[0014] Coating preparation: Bisphenol A epoxy resin, anhydride curing agent, dimethyl nylonate, and butanone were premixed in proportion at a speed of 500 rpm. After 10 minutes, the two were fully mixed to form a uniform premix. Surface-modified nano-SiO2 was then added and ultrasonic-assisted dispersion was performed for 20 minutes. Subsequently, silver-coated copper nanowires were added under nitrogen protection for shear dispersion. Microcapsules were then added and gently stirred and dispersed for 15 minutes. Finally, a photoinitiator TPO-L was added under light-shielding conditions to obtain a weight-reducing window strengthening coating.

[0015] Screen printing: Fix the PC board after plasma activation treatment on the screen printing workbench, fit the screen tightly and correctly on the PC board, control the humidity gradient and pour the weight-reducing window strengthening coating into the screen. Use a scraper to evenly scrape the screen to transfer the weight-reducing window strengthening coating through the pattern part of the screen to the surface of the PC board;

[0016] Post-processing: After the printed PC board is left to evaporate naturally at room temperature, it is then placed in an oven for gradient temperature drying. The dried PC board is then pre-cured at low temperature and then placed in irradiation equipment for final curing. After the final curing, the PC board is annealed to obtain the PC board after the weight-reducing window strengthening coating is completed.

[0017] Preferably, the screen in the screen printing is 62T, the line width accuracy is ±0.05mm, the power of the plasma activation treatment is 300w, the treatment time is 90s, the angle between the scraper and the screen is 72±1°, and the gradient control humidity is specifically: 90% RH for 60 minutes, 60% RH for 60 minutes, and 40% RH for 60 minutes.

[0018] Preferably, the oven temperature in the post-treatment is gradually increased as follows: 80°C for 10 minutes, 120°C for 30 minutes, and 160°C for 60 minutes. The low-temperature pre-curing temperature is 80°C for 30 minutes. The irradiation equipment is 395nm UV with an energy density of 800mJ / cm 2 , annealing temperature is 120℃, and lasts for 1 hour.

[0019] In summary, the present invention has the following beneficial effects:

[0020] 1. Establish a ternary composite system of epoxy resin, nano-SiO2, and metal nanowires. By introducing multiple functional materials, the coating achieves synergistic enhancements in various properties, including wear resistance, conductivity, and self-healing. The different types of nanomaterials complement each other, leveraging their respective strengths to significantly improve the overall performance of the coating.

[0021] 2. Develop a microcapsule self-repair system, using microcapsule technology to encapsulate the repair agent, improving the stability and utilization rate of the repair agent, and realizing the efficient self-repair function of the coating. When the coating is damaged, the microcapsule can release the repair agent in time to repair the damaged area, thereby extending the service life of the coating.

[0022] 3. Through the three-in-one process of gradient dispersion, dynamic humidity control and step curing, the dispersion process, humidity environment and curing conditions can be precisely controlled to ensure the quality and performance of the coating is stable and reliable. This integrated process route can effectively solve the connection problem between each process link and improve production efficiency and product quality. DETAILED DESCRIPTION

[0023] The following is a further description of the specific embodiments of the present invention, which does not limit the present invention.

[0024] A weight-reducing window strengthening coating comprises a base material and functional additives. The base material is bisphenol A epoxy resin E-51 epoxy resin and an anhydride curing agent methyltetrahydrophthalic anhydride. The epoxy value of E-51 epoxy resin is 0.51 to 0.54 mol / g. Bisphenol A epoxy resin is the core film-forming substance. The epoxy groups in its molecules can react with the active hydrogen of the PC board substrate to form chemical bonds. At the same time, the molecular chains are entangled with each other, giving the coating excellent adhesion and firmly adhering to the PC board surface. The benzene ring and ether bond structure ensure chemical stability, making it resistant to corrosion by substances such as acids and alkalis. In addition, its high transparency and regular molecular structure provide the coating with excellent mechanical strength after curing while maintaining good optical properties, ensuring efficient light transmission with minimal scattering. Under heating or catalysis, the anhydride curing agent methyltetrahydrophthalic anhydride undergoes a cross-linking reaction with the epoxy groups of the epoxy resin to generate ester bonds, forming a dense three-dimensional cross-linked network, which significantly improves the hardness and heat resistance of the coating, allowing the coating to maintain morphological stability at high temperatures. At the same time, the dense structure effectively blocks the invasion of foreign substances, greatly enhances the wear and corrosion resistance, and comprehensively optimizes the coating performance.

[0025] The functional additives include surface-modified nano-SiO2, UV photoinitiator TPO-L, microcapsules and a dispersion system. The dispersion system is dimethyl nylonate and a combined solvent. The mass fractions of the above components in the coating are as follows: bisphenol A epoxy resin accounts for 50-60wt%, anhydride curing agent accounts for 12-20wt%, surface-modified nano-SiO2 accounts for 1.5-3wt%, UV photoinitiator accounts for 2-4wt%, silver-coated copper nanowires account for 1.5-3wt%, microcapsules account for 3-5wt%, dimethyl nylonate accounts for 10-15wt%, and butanone accounts for 8-10wt%.

[0026] Surface-modified nano-SiO2 is treated with the silane coupling agent KH-570, resulting in a surface grafting rate of 85-92% and a particle size of 20nm. This significantly improves the compatibility and dispersion uniformity of the nano-SiO2 with the epoxy resin matrix. The modified nano-SiO2 resists agglomeration in the coating and is evenly distributed throughout the coating system, leveraging its advantages of high hardness, wear resistance, and transparency. This significantly improves the coating's wear and scratch resistance while maintaining a high light transmittance, ensuring an optimal balance between optical and mechanical properties.

[0027] UV photoinitiator TPO-L is introduced to construct a dual curing mechanism. Under light conditions, the UV photoinitiator decomposes to produce active free radicals, which trigger the cross-linking reaction of the film-forming substance, improve the hardness and flexibility of the coating, and make the coating have better wear resistance and impact resistance. At the same time, the thermal curing process can also be carried out in coordination to further ensure the performance of the coating.

[0028] The silver-coated copper nanowires have an outer silver layer thickness of 5-8nm and an inner copper layer thickness of 10-15nm, with an aspect ratio greater than 1000. This fully utilizes the high conductivity of silver to ensure rapid electromagnetic signal transmission while utilizing the copper core to reduce cost and weight. Within the coating, the silver-coated copper nanowires intertwine to form conductive pathways. Without affecting the coating's original optical properties, they effectively block electromagnetic interference and reflect or absorb electromagnetic radiation. This provides a reliable electromagnetic shielding solution for applications with stringent electromagnetic compatibility requirements, such as aerospace and electronic equipment, ensuring stable operation in complex electromagnetic environments.

[0029] The microcapsules have a particle size of 5 to 10 nm and a coverage rate of no less than 95%. The microcapsule material is selected from gelatin, gum arabic, polyvinyl alcohol, or polylactic acid. The core material of the microcapsule comprises 82 wt% bisphenol A epoxy resin, 8 wt% curing agent, and 10 wt% diluent. The curing agent is selected from polyamide, amine compound, or acid anhydride compound, and the diluent is selected from acetone or toluene. The repair agent is encapsulated in the coating using microencapsulation technology, achieving the coating's self-healing function. When the coating is damaged, the microcapsules rupture when heated to 120°C, for example, releasing the repair agent to quickly repair the damaged area and extend the coating's service life.

[0030] A construction process for a weight-reducing vehicle window strengthening coating comprises the following steps:

[0031] Coating preparation: Bisphenol A epoxy resin, anhydride curing agent, dimethyl nylonate, and butanone were premixed in proportion at a speed of 500 rpm. After 10 minutes, the two were fully mixed to form a uniform premix. Surface-modified nano-SiO2 was then added and ultrasonic-assisted dispersion was performed for 20 minutes. Subsequently, silver-coated copper nanowires were added under nitrogen protection for shear dispersion. Microcapsules were then added and gently stirred and dispersed for 15 minutes. Finally, a photoinitiator TPO-L was added under light-shielding conditions to obtain a weight-reducing window strengthening coating.

[0032] Screen printing: Take the PC board after plasma activation treatment and fix it on the screen printing workbench to ensure that there is no dust, oil or other impurities attached to it to avoid affecting the adhesion of the coating. Fit the screen tightly and correctly on the PC board. Gradiently control the humidity and pour the weight-reducing window strengthening coating into the screen. Use a scraper to evenly scrape the screen to transfer the weight-reducing window strengthening coating through the pattern part of the screen to the surface of the PC board.

[0033] Post-processing: After the printing is completed, the PC board is left to evaporate naturally at room temperature, and then placed in an oven for gradient temperature drying to gradually evaporate the moisture and solvent inside the coating, reduce the generation of internal stress, and improve the adhesion and stability of the coating. The dried PC board is then pre-cured at low temperature and then placed under irradiation equipment for final curing to fully cure the coating, so that it has excellent hardness, wear resistance and chemical corrosion resistance. After the final curing is completed, the PC board is annealed to further release the internal stress inside the coating, improve the stability and durability of the coating, and obtain the PC board after the weight-reducing window strengthening coating construction is completed.

[0034] The screen used in screen printing is 62T with a line width accuracy of ±0.05mm. The screen is cleaned and degreased to ensure that the coating can pass through the screen smoothly and adhere evenly. The power of the plasma activation treatment is 300w, the treatment time is 90s, the angle between the scraper and the screen is 72±1°, and the gradient humidity control is specifically: 90% RH for 60 minutes, 60% RH for 60 minutes, and 40% RH for 60 minutes.

[0035] The gradient temperature rise of the oven in the post-treatment is: 80℃ for 10 minutes, 120℃ for 30 minutes, and 160℃ for 60 minutes. The low-temperature pre-curing temperature is 80℃ for 30 minutes. The irradiation equipment is 395nm UV with an energy density of 800mJ / cm 2 , annealing temperature is 120℃, and lasts for 1 hour.

[0036] Example 1

[0037] A weight-reducing vehicle window strengthening coating comprises the following components: 50 wt% of bisphenol A epoxy resin, 15 wt% of an anhydride curing agent, 3 wt% of surface-modified nano-SiO2, 2 wt% of a UV photoinitiator, 3 wt% of silver-coated copper nanowires, 3 wt% of microcapsules, 15 wt% of dimethyl nylonate, and 9 wt% of butanone.

[0038] The capsule material of the microcapsule is gelatin, and the core material of the microcapsule includes 82 wt% of bisphenol A epoxy resin, 8 wt% of curing agent and 10 wt% of diluent. The curing agent is polyamide and the diluent is acetone.

[0039] The above coating materials are used to prepare weight-reducing car window reinforced coating PC boards.

[0040] Example 2

[0041] A weight-reducing vehicle window strengthening coating comprises the following components: 55 wt% of bisphenol A epoxy resin, 12 wt% of an anhydride curing agent, 3 wt% of surface-modified nano-SiO2, 2 wt% of a UV photoinitiator, 3 wt% of silver-coated copper nanowires, 5 wt% of microcapsules, 10 wt% of dimethyl nylonate, and 10 wt% of butanone.

[0042] The capsule material of the microcapsule is gum arabic, and the core material of the microcapsule includes 82 wt% of bisphenol A epoxy resin, 8 wt% of curing agent and 10 wt% of diluent. The curing agent is an amine compound and the diluent is acetone.

[0043] The above coating materials are used to prepare weight-reducing car window reinforced coating PC boards.

[0044] Example 3

[0045] A weight-reducing vehicle window strengthening coating comprises the following components: 60 wt% of bisphenol A epoxy resin, 12 wt% of an anhydride curing agent, 1.5 wt% of surface-modified nano-SiO2, 2 wt% of a UV photoinitiator, 3 wt% of silver-coated copper nanowires, 3 wt% of microcapsules, 10 wt% of dimethyl nylonate, and 8.5 wt% of butanone.

[0046] The capsule material of the microcapsule is polyvinyl alcohol, and the core material of the microcapsule includes 82 wt% of bisphenol A epoxy resin, 8 wt% of curing agent and 10 wt% of diluent. The curing agent is an amine compound, and the diluent is one of toluene.

[0047] The above coating materials are used to prepare weight-reducing car window reinforced coating PC boards.

[0048] Example 4

[0049] A weight-reducing vehicle window strengthening coating comprises the following components: 55 wt% of bisphenol A epoxy resin, 15 wt% of an anhydride curing agent, 3 wt% of surface-modified nano-SiO2, 3 wt% of a UV photoinitiator, 2 wt% of silver-coated copper nanowires, 4 wt% of microcapsules, 10 wt% of dimethyl nylonate, and 8 wt% of butanone.

[0050] The capsule material of the microcapsule is polylactic acid, and the core material of the microcapsule includes 82 wt% of bisphenol A epoxy resin, 8 wt% of curing agent and 10 wt% of diluent. The curing agent is an acid anhydride compound, and the diluent is toluene.

[0051] The above coating materials are used to prepare weight-reducing car window reinforced coating PC boards.

[0052] The PC board prepared in Example 4 and conventional glass were subjected to performance tests. The electromagnetic shielding test was conducted according to the IEEE 299 standard method, with a passing standard of not less than 40 dB at 1 GHz. The self-repair efficiency was conducted according to the ASTM D3363 standard method, with a passing standard of scratch repair ≥ 90%. The ultra-low temperature resistance was conducted according to the GJB 150.4 standard method, with a passing standard of no cracking at -70°C × 50 cycles. The specific test data are shown below.

[0053]

[0054]

[0055] It can be seen from the above data that the technical solution of this application achieves synergistic enhancement of the coating's multiple properties such as wear resistance, conductivity, and self-repair. At the same time, the prepared weight-reducing window reinforced coating PC board is used in the aircraft field, which is 53% lighter than traditional glass, effectively reducing the weight of the aircraft and improving fuel efficiency and flight performance. At the same time, it has passed the MIL-STD-810G dust test (wind speed 18m / s×8h), proving that it has good weather resistance and stability in harsh environments, and realizes the integration of EMI shielding (42dB) and anti-icing coating (contact angle>150°), meeting the aircraft's requirements for electromagnetic compatibility and anti-icing performance, and solving the technical difficulties of lightweight transparent material multifunctional coatings. It is particularly suitable for high-end application scenarios such as aircraft windows, high-speed rail side windows, and panoramic skylights of new energy vehicles.

[0056] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art may make various modifications or equivalent substitutions to the present invention within the essence and protection scope of the present invention, and such modifications or equivalent substitutions should also be deemed to fall within the protection scope of the technical solution of the present invention.

Claims

1. A weight-reducing vehicle window strengthening coating, characterized in that: The coating comprises a matrix material and functional additives, wherein the matrix material is bisphenol A epoxy resin and an anhydride curing agent, the functional additives comprise surface-modified nano-SiO2, a UV photoinitiator, microcapsules and a dispersion system, the dispersion system is dimethyl nylonate and a combined solvent, and the mass fractions of the above components in the coating are as follows: bisphenol A epoxy resin accounts for 50-60wt%, anhydride curing agent accounts for 12-20wt%, surface-modified nano-SiO2 accounts for 1.5-3wt%, UV photoinitiator accounts for 2-4wt%, silver-coated copper nanowires account for 1.5-3wt%, microcapsules account for 3-5wt%, dimethyl nylonate accounts for 10-15wt%, and butanone accounts for 8-10wt%.

2. The weight-reducing vehicle window strengthening coating according to claim 1, characterized in that: The bisphenol A epoxy resin is E-51 epoxy resin, and the epoxy value is 0.51-0.54 mol / g.

3. The weight-reducing vehicle window strengthening coating according to claim 1, characterized in that: The acid anhydride curing agent is methyltetrahydrophthalic anhydride.

4. The weight-reducing vehicle window strengthening coating according to claim 1, characterized in that: The surface-modified nano-SiO2 is nano-SiO2 that has been surface-treated with a silane coupling agent KH-570, has a surface grafting rate of 85-92%, and a particle size of 20 nm.

5. The weight-reducing vehicle window strengthening coating according to claim 1, characterized in that: The UV photoinitiator is TPO-L.

6. The weight-reducing vehicle window strengthening coating according to claim 1, characterized in that: The thickness of the outer silver layer of the silver-clad copper nanowire is 5-8 nm, the thickness of the inner copper layer is 10-15 nm, and the aspect ratio is greater than 1000.

7. The weight-reducing vehicle window strengthening coating according to claim 1, characterized in that: The microcapsule particle size is 5 to 10 nm, the coverage rate is not less than 95%, the capsule material of the microcapsule is selected from one of gelatin, gum arabic, polyvinyl alcohol or polylactic acid, the core material of the microcapsule includes 82wt% of bisphenol A epoxy resin, 8wt% of a curing agent and 10wt% of a diluent, the curing agent is selected from one of polyamide, amine compound or acid anhydride compound, and the diluent is selected from one of acetone or toluene.

8. A construction process for a weight-reducing vehicle window strengthening coating, characterized in that: The steps include: Coating preparation: Bisphenol A epoxy resin, anhydride curing agent, dimethyl nylonate, and butanone were premixed in proportion at a speed of 500 rpm. After 10 minutes, the two were fully mixed to form a uniform premix. Surface-modified nano-SiO2 was then added and ultrasonic-assisted dispersion was performed for 20 minutes. Subsequently, silver-coated copper nanowires were added under nitrogen protection for shear dispersion. Microcapsules were then added and gently stirred and dispersed for 15 minutes. Finally, a photoinitiator TPO-L was added under light-shielding conditions to obtain a weight-reducing window strengthening coating. Screen printing: Fix the PC board after plasma activation treatment on the screen printing workbench, fit the screen tightly and correctly on the PC board, control the humidity gradient and pour the weight-reducing window strengthening coating into the screen. Use a scraper to evenly scrape the screen to transfer the weight-reducing window strengthening coating through the pattern part of the screen to the surface of the PC board; Post-processing: After the printed PC board is left to evaporate naturally at room temperature, it is then placed in an oven for gradient temperature drying. The dried PC board is then pre-cured at low temperature and then placed in irradiation equipment for final curing. After the final curing, the PC board is annealed to obtain the PC board after the weight-reducing window strengthening coating is completed.

9. The construction process of a weight-reducing vehicle window strengthening coating according to claim 8, characterized in that: The screen used in the screen printing is 62T, the line width accuracy is ±0.05mm, the power of the plasma activation treatment is 300w, the treatment time is 90s, the angle between the scraper and the screen is 72±1°, and the gradient control humidity is specifically: 90% RH for 60 minutes, 60% RH for 60 minutes, and 40% RH for 60 minutes.

10. The construction process of a weight-reducing vehicle window strengthening coating according to claim 8, characterized in that: The oven temperature in the post-treatment was gradually increased as follows: 80°C for 10 minutes, 120°C for 30 minutes, and 160°C for 60 minutes. The low-temperature pre-curing temperature was 80°C for 30 minutes. The irradiation equipment was 395nm UV with an energy density of 800mJ / cm 2 , annealing temperature is 120℃, and lasts for 1 hour.

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