Optical glass AR-AF coating stripping liquid without damaging printing ink and glass and preparation method of optical glass AR-AF coating stripping liquid

Abstract

The invention discloses an optical glass AR-AF coating film stripping liquid without damaging printing ink and glass and a preparation method thereof, and belongs to the field of optical element cleaning. The film stripping liquid is prepared by compounding organic alkali, a buffering agent, an auxiliary complexing agent and two specifically designed novel compounds. The preparation method is characterized in that the organic alkali is dissolved in water to form an alkaline basic solution, the two novel compounds of the targeted anti-reflection coating and the anti-fingerprint coating are premixed and then added into the alkaline solution, finally, the penetration enhancer and the ink protective agent are added, the mixture is cured and filtered after the pH value is precisely adjusted, and the target anti-reflection fingerprint-resistant coating is obtained. The invention further provides a preparation method of the two core compounds in detail. The film stripping liquid can efficiently remove multiple layers of film systems under mild conditions, does not corrode, swell or damage printing ink marks on the surface of a glass substrate and a glass body, solves the industrial problem that a traditional strong-acid and strong-alkali film stripping liquid damages the substrate, and is suitable for reworking and regeneration of high-end optical glass products.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of optical element cleaning, in particular to an optical glass AR-AF coating stripping solution without damaging ink and glass and a preparation method thereof. BACKGROUND

[0002] The optical glass surface is coated with an anti-reflective and anti-fingerprint coating, which has become a key process in the manufacture of smart phones, tablets, camera lenses and various precision optical instruments. Such coatings can effectively reduce surface reflectivity, improve optical transmission performance, and at the same time provide excellent hydrophobic and oleophobic properties, enhance anti-pollution ability and user experience. However, in the process of high-precision and mass production, due to process fluctuations, equipment parameter deviations or environmental factors, it is inevitable that some substandard products will be produced. These substandard products need to be reworked, and the defective coating is removed and re-coated to meet product quality standards. In addition, in the research and development stage or small batch trial production, high-value optical prototypes or molds also need a technology that can remove the coating without damage, so as to realize the reuse of the substrate and reduce production costs. Therefore, efficient and non-destructive stripping technology has become a key link to improve product yield and control production costs.

[0003] At present, the stripping method commonly used in the industry is still mainly based on strong chemical etching, of which the most typical is the use of strong acid systems such as hydrofluoric acid, concentrated sulfuric acid, concentrated nitric acid, or high-concentration sodium hydroxide, potassium hydroxide, etc. Strong alkali solution. These methods rely on strong corrosive reagents to chemically dissolve or peel off the coating components. However, such methods have significant limitations. Strong acids, especially hydrofluoric acid, can chemically react with the main component of glass, silicon dioxide, causing the glass body to be corroded, resulting in a decrease in surface smoothness, a fogging phenomenon, and even changes in the geometry and optical uniformity of the substrate, making the element completely scrap. At the same time, the strong chemical action will also attack the epoxy resin or acrylic resin ink commonly used on the glass surface for brand identification and parameter marking, causing swelling, blurring, falling off or discoloration, and damaging the integrity of the product identification. More importantly, strong acid and strong alkali reagents have extremely high operation risks and environmental hazards, especially the toxicity and strong penetration of hydrofluoric acid, posing a serious challenge to safety production and environmental protection.

[0004] To overcome the defects of traditional methods, some researches have tried to develop more mild stripping systems in recent years. For example, organic amine complexing agents are combined with weak bases to selectively dissolve metal oxide layers, or oxidizing agents such as persulfate are used to decompose organic polymer layers under heating conditions. These methods have reduced the attack on the glass substrate to some extent, but have not completely solved all problems. They generally have problems such as low stripping efficiency, long processing time, or lack of universality for only being effective for specific types of coatings. More importantly, there is still a lack of sufficient research and reliable solutions for how to effectively protect complex printed inks. Therefore, there is an urgent need for a completely new stripping technology that must be able to efficiently and quickly remove various types of anti-reflective and anti-fingerprint composite coatings, while absolutely ensuring the integrity of the microstructure and surface optical properties of the glass substrate, completely protecting the integrity of various ink markings, and finally meeting the high standards of safety, environmental protection and operational convenience required by modern chemical production. SUMMARY

[0005] The purpose of the present application is to provide an optical glass AR-AF coating stripping solution that does not damage inks and glass and a preparation method thereof, which solves the technical problems that existing stripping solutions inevitably corrode glass substrates and damage surface printed ink markings when removing optical glass AR-AF coatings.

[0006] The present application achieves the above-mentioned purpose by the following technical solutions: A preparation method of an optical glass AR-AF coating stripping solution that does not damage inks and glass, comprising the following steps: S1. Deionized water is added to a reaction kettle, and after stirring and dissolving by dropwise adding triethanolamine, potassium carbonate and potassium gluconate are sequentially added, and stirring is performed until an alkaline base solution is formed; S2. In a premix container pre-added with deionized water, a multi-dentate zwitterionic complexing agent targeting AR coatings is added and stirred to dissolve; then a fluorophilic surfactant stripping agent targeting AF coatings is dropwise added, and stirring is continued to obtain a premix solution; the premix solution is added to the alkaline base solution, and stirring is continued; then ethylene glycol phenyl ether and polyacrylamide solution are sequentially added; S3. The system is warmed to 35-40℃ for aging and stirring; after aging is completed, it is cooled to room temperature, and a pH of 10.3-10.7 is adjusted with tetramethylammonium hydroxide or citric acid solution as an adjusting agent, and the stripping solution is filtered through a polypropylene filter bag.

[0007] In the present application, the overall mechanism of the stripping solution is based on the synergistic effect of two core compounds. In a weakly alkaline working environment, the multi-dentate amphoteric complexing agent targeting the AR coating plays its main function. Its multiple carboxylate and amine groups in the molecule can form strong chelation with metal ions in the anti-reflective coating, forming a water-soluble complex, thereby destroying the lattice structure of the metal oxide layer, and making it dissociate from the glass surface. At the same time, the amphoteric nature of the complexing agent ensures that it only has weak interaction with the silica network on the glass surface, avoiding the erosive etching of hydrofluoric acid. On the other hand, the fluorine-affinity surfactant peeling agent targeting the AF coating acts on the hydrophobic anti-fingerprint coating through its unique structure. The end perfluoroalkyl chain penetrates into the interior of the fluorine-containing polymer AF layer through fluorine-fluorine interaction, while the other end silane group has affinity with the AR layer or the glass surface. Under weakly alkaline conditions, the ester bond in the molecular structure will undergo slow hydrolysis and breakage, which internally destroys the cross-linked network structure of the AF layer, and effectively disperses the broken fragments in the aqueous solution using its surfactant properties, thereby achieving peeling. The whole system works under mild alkaline conditions and is equipped with an ink protector, so as to efficiently peel the AR-AF multilayer film system while ensuring the integrity of the glass substrate and the surface ink mark is not damaged.

[0008] According to the preferred embodiment of the present application, in step S1, the time for dropping triethanolamine is 10-15 min.

[0009] According to the preferred embodiment of the present application, in step S2, the time for stirring to dissolve is 30-45 min.

[0010] According to the preferred embodiment of the present application, the preparation method of the multi-dentate amphoteric complexing agent targeting the AR coating comprises: A1, dissolve 2,4-dibromo-6-((bis(2-((tert-butoxycarbonyl)amino)ethyl)amino) methyl) phenol in anhydrous N, N-dimethylformamide, add sodium hydride under argon protection and ice water bath cooling, and stir the reaction; then add a pre-mixed suspension of 3-chloro-N, N-dimethylpropylamine hydrochloride and triethylamine, and react at room temperature; A2. After the reaction was complete, the mixture was poured into ice water and extracted with ethyl acetate. The organic phase was washed with saturated brine, dried over anhydrous sodium sulfate, and distilled under reduced pressure to obtain the crude product. The crude product was dissolved in dichloromethane, and trifluoroacetic acid was added. The mixture was stirred at room temperature. After the reaction was complete, the mixture was distilled under reduced pressure to obtain a viscous oil. The viscous oil was dissolved in a methanol / water mixture, and tert-butyl bromoacetate and N,N-diisopropylethylamine were added. The mixture was reacted at 58-62°C. After the reaction was complete, the residue was distilled under reduced pressure and dissolved in dichloromethane. Trifluoroacetic acid was added again, and the mixture was reacted at room temperature. The residue was then dissolved in deionized water and purified by passing it through a strongly acidic cation exchange resin column.

[0011] In this invention, the preparation of the multidentate zwitterionic complexing agent for the targeted AR coating is a multi-step organic synthesis process. Its core mechanism lies in the gradual construction of a complex molecule possessing both strong complexing ability and zwitterionic properties. The key reaction in the first step is the nucleophilic substitution of a haloalkane by a phenoxy anion. Under the action of sodium hydride, the phenolic hydroxyl group of the starting material phenolic compound is deprotonated to form a highly reactive phenoxy anion. This anion then attacks the chlorine atom position in the trichloropropylamine derivative molecule, undergoing an intermolecular nucleophilic substitution reaction, thereby successfully introducing the quaternary ammonium salt precursor into the molecular framework. This step must be carried out at a low temperature and inert atmosphere to prevent side reactions. The subsequent steps involve the removal of protecting groups and the introduction of carboxyl groups. Under acidic conditions, trifluoroacetic acid can efficiently cleave the tert-butyloxycarbonyl protecting group, re-exposing the protected amine group as a free amine group, providing an active site for subsequent reactions. These newly generated free primary amine groups then undergo a nucleophilic substitution reaction with tert-butyl bromoacetate. The amine group acts as a nucleophile, attacking the carbon atom of tert-butyl bromoacetate and introducing the carboxyl group into the molecule in the protected form of tert-butyl ester, constructing a multidentate complex structure similar to ethylenediaminetetraacetic acid. Finally, treatment with trifluoroacetic acid simultaneously removes all remaining tert-butyl ester and tert-butyloxycarbonyl protecting groups, exposing the final carboxylate and amine groups. A stable zwitterionic structure is formed through the intramolecular interaction between the carboxylate and the quaternary ammonium cation. The final purification step using a strongly acidic cation exchange resin effectively removes residual inorganic salt ions and byproducts from the reaction through ion exchange, yielding a high-purity target zwitterionic complexing agent.

[0012] According to a preferred embodiment of the present invention, in step A1, the stirring reaction time is 30-40 min; the reaction time to room temperature is 12-14 h.

[0013] According to a preferred embodiment of the present invention, in step A2, the stirring reaction time at room temperature is 4-6 hours.

[0014] According to a preferred embodiment of the present invention, the method for preparing the fluorine-affinity surfactant stripper for the targeted AF coating includes: B1. Dissolve perfluorohexylethanol and succinic anhydride in anhydrous tetrahydrofuran, add 4-dimethylaminopyridine, and stir the reaction at room temperature; after the reaction is complete, evaporate under reduced pressure to obtain perfluorohexylethylsuccinic acid monoester. B2. Perfluorohexyl ethyl succinate monoester was dissolved in acetonitrile, and N,N'-dicyclohexylcarbodiimide and N-hydroxysuccinimide were added. The mixture was activated in an ice bath and filtered. N-(3-triethoxysilylpropyl)ethylenediamine and triethylamine dissolved in acetonitrile were added to the filtrate and the mixture was reacted at room temperature. After the reaction was completed, the mixture was filtered, and the filtrate was concentrated under reduced pressure to obtain the crude product. The crude product was purified by silica gel column chromatography.

[0015] In this invention, the synthetic route for the fluorine-affinity surfactant stripper targeting the AF coating cleverly utilizes a stepwise condensation strategy. Its core mechanism lies in constructing a "block" molecule that simultaneously contains a fluorocarbon chain, a breakable linker arm, and a silane anchoring group. The reaction begins with the ring-opening esterification of perfluorohexylethanol and succinic anhydride. In perfluorohexylethanol, the hydroxyl group acts as a nucleophile, attacking the carbonyl carbon atom of the succinic anhydride, causing the anhydride ring to open and forming a perfluorohexylethyl succinate monoester. This molecule has a long fluorocarbon chain at one end and retains a free carboxyl group at the other end; this reaction is catalyzed by an organic base. Next, this free carboxyl group needs to be activated to react with an amine. In the presence of a carbodiimide condensing agent, the carboxyl group first reacts with the condensing agent to generate a highly reactive intermediate. This intermediate rapidly reacts with N-hydroxysuccinimide to generate a more stable amine-active ester. The carbonyl carbon atom of this active ester has higher electrophilicity and is highly susceptible to attack by amine nucleophiles. Finally, N-triethoxysilylpropylethylenediamine, as a bifunctional molecule, uses its primary amine group at one end as a strong nucleophile to selectively attack the carbonyl carbon atom of the aforementioned active ester, undergoing an amidation reaction to form a stable amide bond. This covalently links the fluorocarbon segment to the silane anchoring group. The final reaction mixture is purified by silica gel column chromatography. The mechanism utilizes the difference in adsorption capacity of silica gel immobilizers for products of different polarities, and elution is performed using a solvent system with gradually changing polarity, thereby achieving effective separation of the target product and byproducts to obtain a pure fluorine-affinity surfactant stripper.

[0016] According to a preferred embodiment of the present invention, in step B1, the stirring reaction time at room temperature is 12-14 hours.

[0017] According to a preferred embodiment of the present invention, in step B2, the activation time under ice bath is 2-4 hours.

[0018] The present invention also provides a method for preparing an optical glass AR-AF coating stripping solution that does not damage ink and glass, resulting in an optical glass AR-AF coating stripping solution that does not damage ink and glass.

[0019] The beneficial effects of this invention are as follows: The stripping solution provided by this invention possesses superior technical effects, with its core advantage lying in the perfect combination of highly efficient stripping capability and substrate protection performance. This stripping solution can quickly and thoroughly remove various types of anti-reflective and anti-fingerprint composite coatings under mild conditions, with a complete and residue-free stripping process. Particularly noteworthy is its unique weakly alkaline formula and specifically designed active ingredients, which ensure zero damage to the glass substrate surface throughout the stripping process. The treated glass surface retains its original smoothness, free from haze, scratches, and corrosion, and its optical properties remain unchanged, fully meeting the stringent requirements of high-end optical components for substrate quality.

[0020] This invention demonstrates significant technical advantages in protecting the integrity of inks. The neutral acid-base environment, combined with specially formulated ink-protecting components, ensures comprehensive protection against common epoxy or acrylic resin screen printing inks found on glass surfaces. The treated ink markings show no swelling, peeling, or discoloration, maintaining a clear visual effect and complete marking function. This characteristic completely solves the technical problem of ink damage in traditional film removal processes, providing a reliable guarantee for the rework and repair of high-value-added products.

[0021] From both a production process and environmental perspective, this invention also represents a significant advancement. This stripping solution system contains no high-risk components such as strong acids or alkalis, greatly reducing safety hazards and environmental burden during production. Simultaneously, the formula possesses excellent acid-base buffering capacity and thermal stability, maintaining stable performance over a wide temperature range, extending the service life of the bath, and reducing production costs. Its broad process applicability can handle coating systems prepared using various coating processes, providing the optical glass manufacturing industry with a highly efficient, safe, and environmentally friendly solution. Detailed Implementation

[0022] The following detailed embodiments are only used to further illustrate this application and should not be construed as limiting the scope of protection of this application. Those skilled in the art can make some non-essential improvements and adjustments to this application based on the above application content.

[0023] The following is information on domestic suppliers of key related equipment and materials: The reactor was purchased from Zhengzhou Yuxin New Energy Chemical Equipment Co., Ltd.

[0024] The triethanolamine was purchased from Shandong Longhui Chemical Co., Ltd.

[0025] The potassium carbonate was purchased from Shanxi Wentong Potassium Salt Group Co., Ltd.

[0026] The potassium gluconate was purchased from Ningbo Yingqian Technology Co., Ltd.

[0027] The ethylene glycol phenyl ether was purchased from Jiangsu Changkai Chemical Co., Ltd.

[0028] The polyacrylamide was purchased from Shandong Jinyueyuan New Materials Co., Ltd.

[0029] The tetramethylammonium hydroxide was purchased from Zhenjiang Runjing High Purity Chemical Technology Co., Ltd.

[0030] The citric acid was purchased from Wuhan Xin Haiyang Chemical Co., Ltd.

[0031] The 2,4-dibromo-6-((bis(2-((tert-butoxycarbonyl)amino)ethyl)amino)methyl)phenol was purchased from Shanghai Haohong Biomedical Technology Co., Ltd.

[0032] The N,N-dimethylformamide was purchased from Shandong Jinling Chemical Co., Ltd.

[0033] The sodium hydride was purchased from Shanghai Aladdin Biochemical Technology Co., Ltd.

[0034] The 3-chloro-N,N-dimethylpropylamine hydrochloride was purchased from Shanghai Bid Pharmaceutical Technology Co., Ltd.

[0035] The triethylamine was purchased from Shandong Jinling Chemical Co., Ltd.

[0036] The ethyl acetate was purchased from Jiangsu Hualun Chemical Co., Ltd.

[0037] The anhydrous sodium sulfate was purchased from Sinopharm Chemical Reagent Co., Ltd.

[0038] The tert-butyl bromoacetate was purchased from Shanghai Maclean Biochemical Technology Co., Ltd.

[0039] The N,N-diisopropylethylamine was purchased from Shanghai Aladdin Biochemical Technology Co., Ltd.

[0040] The trifluoroacetic acid was purchased from Changzhou Kefeng Chemical Co., Ltd.

[0041] The perfluorohexylethanol was purchased from Zhejiang Juhua Co., Ltd.

[0042] The succinic anhydride was purchased from Sinopharm Chemical Reagent Co., Ltd.

[0043] The 4-dimethylaminopyridine was purchased from Shanghai Aladdin Biochemical Technology Co., Ltd.

[0044] The N,N'-dicyclohexylcarbodiimide was purchased from Jiangsu Yongjian Pharmaceutical Technology Co., Ltd.

[0045] The N-hydroxysuccinimide was purchased from Xi'an Hangjie Chemical Technology Co., Ltd.

[0046] The N-(3-triethoxysilylpropyl)ethylenediamine was purchased from Hubei Xinlantian New Materials Co., Ltd.

[0047] The EDTA disodium was purchased from Shandong Baisheng Biotechnology Co., Ltd.

[0048] The sodium dodecyl sulfate was purchased from Zhejiang Zanyu Technology Co., Ltd.

[0049] The OP-10 emulsifier was purchased from Liaoning Kelon Fine Chemical Co., Ltd.

[0050] The sodium citrate was purchased from Shandong Yingxuan Industrial Co., Ltd.

[0051] Example 1:

[0052] First, a multidentate zwitterionic complexing agent for targeted AR coatings was prepared. 5.0 g of 2,4-dibromo-6-((bis(2-((tert-butoxycarbonyl)amino)ethyl)amino)methyl)phenol was accurately weighed and placed in a 250 mL dry three-necked flask. 30 g of anhydrous N,N-dimethylformamide was added, and a mechanical stirrer, thermometer, and argon inlet tube were installed. Argon gas was introduced three times to replace the air in the reaction system, ensuring the system was under an inert atmosphere. The reaction flask was cooled to 5°C in an ice-water bath, and the stirrer was started at 300 rpm. 1.2 g of sodium hydride was slowly added in portions, controlling the addition rate to keep the reaction temperature below 10°C. After the addition was complete, the reaction was continued at 8°C with stirring for 30 minutes. Separately, 2.5 g of 3-chloro-N,N-dimethylpropylamine hydrochloride and 1.8 g of triethylamine were premixed in 10 mL of anhydrous N,N-dimethylformamide to prepare a suspension. This suspension was slowly added dropwise to the reaction system at a rate of 0.5 mL per minute using a constant-pressure dropping funnel, with the reaction temperature strictly controlled below 10°C during the addition. After the addition was complete, the ice-water bath was removed, and the reaction system was allowed to naturally warm to 25°C. The reaction was continued at this temperature with stirring for 12 hours, and the reaction progress was monitored by TLC. After the reaction was complete, the reaction solution was slowly poured into a 500 mL beaker containing 100 g of crushed ice. The mixture was extracted three times with 50 g of ethyl acetate, stirring for 5 minutes each time, and allowed to stand for separation. The organic phases were combined and washed twice with 20 g of saturated brine, stirring for 3 minutes each time. 5 g of anhydrous sodium sulfate was added for drying for 3 hours, with intermittent shaking during this period. The drying agent was removed by filtration, and the filtrate was distilled under reduced pressure at 0.09 MPa in a 40°C water bath to remove the solvent, yielding a pale yellow oily crude product. The crude product was dissolved in 20 g of dichloromethane, and 10 g of trifluoroacetic acid was added. The mixture was stirred in a water bath at 25 °C for 4 hours, and the deprotection process was monitored by TLC. After the reaction was complete, the solvent and trifluoroacetic acid were removed by vacuum distillation under a vacuum of 0.08 MPa in a water bath at 35 °C, yielding a viscous oil. This oil was dissolved in a mixed solvent of 20 g of methanol and water (volume ratio 4:1), and 3.0 g of tert-butyl bromoacetate and 5.0 g of N,N-diisopropylethylamine were added. A reflux condenser was installed, and the mixture was heated to 60 °C in an oil bath and stirred for 8 hours, with the reaction progress monitored by TLC. After the reaction was complete, the solvent was removed by vacuum distillation under a vacuum of 0.08 MPa in a water bath at 50 °C. The residue was dissolved in 15 g of dichloromethane, and 8 g of trifluoroacetic acid was added. The mixture was stirred in a water bath at 25 °C for 3 hours. All solvents were removed by vacuum distillation. The residue was dissolved in 50 g of deionized water and passed through a glass column packed with strongly acidic cation exchange resin at a flow rate of 2 mL / min, using water as the eluent. One fraction was collected every 10 mL, and the fractions containing the target product were analyzed by TLC. The combined fractions were freeze-dried at -40 °C and 0.05 MPa for 24 hours to obtain a white solid multidentate zwitterionic complexing agent with a targeted AR coating.

[0053] Next, a fluorine-affinity surfactant stripper for targeting the AF coating was prepared. 4.0 g of perfluorohexylethanol and 1.5 g of succinic anhydride were placed in a 100 mL dry round-bottom flask, followed by 20 g of anhydrous tetrahydrofuran and 0.1 g of 4-dimethylaminopyridine. A molecular sieve drying tube was installed, and the mixture was stirred in an oil bath at 25 °C for 12 hours. The reaction progress was monitored by TLC. After the reaction was complete, the solvent tetrahydrofuran was removed by vacuum distillation under a vacuum of 0.08 MPa in a 40 °C water bath to obtain a white solid perfluorohexylethyl succinate. This product was dissolved in 15 g of anhydrous acetonitrile, and 2.2 g of N,N-dicyclohexylcarbodiimide and 1.3 g of N-hydroxysuccinimide were added. The mixture was placed in an ice-water bath at 5 °C and stirred for 2 hours, resulting in the formation of a large amount of white precipitate. The precipitate was removed by filtration using a sintered glass funnel. 3.0 g of N-(3-triethoxysilylpropyl)ethylenediamine and 2.0 g of triethylamine, pre-dissolved in 10 g of anhydrous acetonitrile, were added to the filtrate. The mixture was stirred in an oil bath at 25°C for 12 hours, and the reaction progress was monitored by TLC. After the reaction was complete, the mixture was filtered, and the filtrate was concentrated under reduced pressure at 0.08 MPa in a water bath at 40°C to obtain the crude product. The crude product was purified by silica gel column chromatography (200-300 mesh silica gel, column size: 3×40 cm) using a gradient elution of a mixed solvent of petroleum ether and ethyl acetate (from 10:1 to 3:1, v / v). Fractions containing the target product were collected every 15 mL and analyzed by TLC. The combined fractions were then concentrated under reduced pressure to obtain a colorless, oily, fluorine-affinity surfactant stripper for targeting AF coatings.

[0054] Finally, the stripping solution was prepared. 700g of deionized water was added to a 2000mL glass reactor. Mechanical stirring was started at 200rpm, and the temperature was maintained at 25℃. 180g of triethanolamine was added dropwise at a rate of 5g per minute through a constant-pressure dropping funnel. After the addition was complete, stirring was continued for 15 minutes to ensure homogeneity. 20g of potassium carbonate and 30g of potassium gluconate were added sequentially, with a 5-minute interval between each addition, and stirring was continued until completely dissolved to form a clear, transparent alkaline base solution. 300g of deionized water was added to a 500mL plastic premix container. Stirring was started at 300rpm, and 85g of the multidentate zwitterionic complexing agent for the targeted AR coating prepared above was slowly added. The temperature was maintained at 25℃, and stirring was continued for 40 minutes until completely dissolved. 58g of the fluorine-affinity surfactant stripping agent for the targeted AF coating prepared above was slowly added dropwise at a rate of 2g per minute. After the addition was complete, stirring was continued at 300rpm for 60 minutes to obtain a homogeneous, milky-white premix solution. The premixed solution was slowly added dropwise to the alkaline base solution in the reactor at a rate of 10 g per minute using a constant-pressure dropping funnel, maintaining the reactor temperature at 25°C during the addition. After the addition was complete, the mixture was stirred at 200 rpm for 60 minutes to ensure thorough mixing. Then, 50 g of ethylene glycol phenyl ether and 15 g of polyacrylamide solution (prepared as a 10% aqueous solution) were added sequentially, with stirring for 15 minutes after each addition. The system was heated to 38°C at a programmed rate of 1°C per minute and maintained at this temperature with stirring at 150 rpm for 120 minutes for aging. After aging, the system was cooled to 25°C at a programmed rate of 2°C per minute, and the pH was finely adjusted to 10.5 using a 25% tetramethylammonium hydroxide aqueous solution. Finally, the stripping solution was filtered through a 1 μm polypropylene filter bag at a pressure of 0.2 MPa to obtain a clear and transparent final product.

[0055] Example 2:

[0056] The specific implementation method is the same as in Example 1, except that 5.0 g of 2,4-dibromo-6-((bis(2-((tert-butoxycarbonyl)amino)ethyl)amino)methyl)phenol was placed in a dry reaction flask, and 30 g of anhydrous N,N-dimethylformamide was added. Argon gas was bubbled through the flask three times to purge the solution, and the mixture was cooled to 5°C in an ice-water bath. 1.2 g of sodium hydride was slowly added, and the temperature was maintained below 10°C while stirring for 35 minutes. 2.5 g of 3-chloro-N,N-dimethylpropylamine hydrochloride was pre-mixed with 1.8 g of triethylamine to prepare a suspension, which was slowly added dropwise to the reaction system. After the addition was complete, the temperature was gradually raised to 25°C, and the reaction was continued with stirring for 13 hours. After the reaction was completed, the reaction solution was slowly poured into 100 g of ice water, extracted three times with 50 g of ethyl acetate, and the organic phases were combined. The mixture was washed twice with 20 g of saturated brine, and dried for 3 hours with 5 g of anhydrous sodium sulfate. After filtration, the solvent was removed by vacuum distillation to obtain a light yellow oily crude product. The crude product was dissolved in 20 g of dichloromethane, and 10 g of trifluoroacetic acid was added. The mixture was stirred at 25 °C for 5 hours. After the reaction, the solvent was removed by vacuum distillation, yielding a viscous oil. This oil was dissolved in a mixture of 20 g of methanol and water, and 3.0 g of tert-butyl bromoacetate and 5.0 g of N,N-diisopropylethylamine were added. The mixture was heated to 59 °C and stirred for 8 hours. After the reaction, the solvent was removed by vacuum distillation. The residue was dissolved in 15 g of dichloromethane, and 8 g of trifluoroacetic acid was added. The mixture was stirred at 25 °C for 4 hours. All solvent was removed by vacuum distillation. The residue was dissolved in 50 g of deionized water and passed through a strongly acidic cation exchange resin column at a flow rate of 2 mL / min. The column was eluted with water, and the target product fraction was collected. After freeze-drying, 8.0 g of a white solid multidentate zwitterionic complexing agent for targeting AR coatings was obtained. Separately, 4.0 g of perfluorohexylethanol and 1.5 g of succinic anhydride were placed in a dry reaction flask, 20 g of anhydrous tetrahydrofuran was added, followed by 0.1 g of 4-dimethylaminopyridine. The mixture was stirred at 25 °C for 13 hours. After the reaction was complete, the solvent was removed by vacuum distillation to obtain a white solid perfluorohexylethyl succinate monoester. This product was dissolved in 15 g of acetonitrile, and 2.2 g of N,N-dicyclohexylcarbodiimide and 1.3 g of N-hydroxysuccinimide were added. The mixture was stirred and activated in an ice-water bath at 5 °C for 3 hours. The precipitate was removed by filtration, and 3.0 g of N-triethoxysilylpropylethylenediamine and 2.0 g of triethylamine, which had been pre-dissolved in 10 g of acetonitrile, were added to the filtrate. The mixture was stirred at 25 °C for 12 hours. After the reaction was complete, the mixture was filtered, and the filtrate was concentrated under reduced pressure to obtain the crude product. The crude product was purified by silica gel column chromatography, followed by gradient elution with a mixed solvent of petroleum ether and ethyl acetate to obtain 5.5 g of a colorless, oily, fluorine-affinity surfactant stripper targeting the AF coating. 710 g of deionized water was added to a 2000 mL reactor, the stirring was started and controlled at 200 rpm, the temperature was maintained at 25 °C, and 170 g of triethanolamine was added dropwise at a rate of 6 g per minute. After the addition was complete, stirring was continued for 15 minutes.Add 18g of potassium carbonate and 25g of potassium gluconate sequentially, 5 minutes apart, stirring until completely dissolved to form a clear alkaline base solution. Add 290g of deionized water to a 500mL premixing container, start stirring at 300rpm, and slowly add 80g of the prepared multidentate zwitterionic complexing agent for the targeted AR coating, maintaining a temperature of 25℃ and stirring for 35 minutes until completely dissolved. Slowly add 55g of the prepared fluorine-affinity surfactant stripping agent for the targeted AF coating at a rate of 1.8g per minute, continuing stirring at 300rpm for 50 minutes after the addition is complete to obtain a homogeneous premix. Slowly add the premix to the alkaline base solution in the reactor at a rate of 9g per minute, maintaining the reactor temperature at 25℃ during the addition, and continuing stirring at 200rpm for 50 minutes after the addition is complete. Add 45g of ethylene glycol phenyl ether and 12g of polyacrylamide solution sequentially, stirring for 15 minutes after each addition. The system was heated to 36°C at a rate of 1°C per minute and maintained at this temperature while stirring at 150 rpm for 110 minutes for aging. After aging, the system was cooled to 25°C at a rate of 2°C per minute, and the pH was adjusted to 10.4 with a 25% tetramethylammonium hydroxide aqueous solution. Finally, the stripping solution was filtered through a 1μm polypropylene filter bag to obtain a clear and transparent final product.

[0057] Example 3:

[0058] The specific implementation method is the same as in Example 1, except that 5.0 g of 2,4-dibromo-6-((bis(2-((tert-butoxycarbonyl)amino)ethyl)amino)methyl)phenol was placed in a dry reaction flask, and 30 g of anhydrous N,N-dimethylformamide was added. Argon gas was bubbled through the flask three times to purge the solution, and the mixture was cooled to 5°C in an ice-water bath. 1.2 g of sodium hydride was slowly added, and the temperature was maintained below 10°C while stirring for 40 minutes. 2.5 g of 3-chloro-N,N-dimethylpropylamine hydrochloride was pre-mixed with 1.8 g of triethylamine to prepare a suspension, which was slowly added dropwise to the reaction system. After the addition was complete, the temperature was gradually raised to 25°C, and the reaction was continued with stirring for 14 hours. After the reaction was complete, the reaction solution was slowly poured into 100 g of ice water, extracted three times with 50 g of ethyl acetate, and the organic phases were combined. The mixture was washed twice with 20 g of saturated brine, and dried for 3 hours with 5 g of anhydrous sodium sulfate. After filtration, the solvent was removed by vacuum distillation to obtain a light yellow oily crude product. The crude product was dissolved in 20 g of dichloromethane, and 10 g of trifluoroacetic acid was added. The mixture was stirred at 25 °C for 6 hours. After the reaction, the solvent was removed by vacuum distillation, yielding a viscous oil. This oil was dissolved in a mixture of 20 g of methanol and water, and 3.0 g of tert-butyl bromoacetate and 5.0 g of N,N-diisopropylethylamine were added. The mixture was heated to 61 °C and stirred for 8 hours. After the reaction, the solvent was removed by vacuum distillation. The residue was dissolved in 15 g of dichloromethane, and 8 g of trifluoroacetic acid was added. The mixture was stirred at 25 °C for 5 hours. All solvent was removed by vacuum distillation. The residue was dissolved in 50 g of deionized water and passed through a strongly acidic cation exchange resin column at a flow rate of 2 mL / min. The column was eluted with water, and the target product fraction was collected. After freeze-drying, 8.8 g of a white solid multidentate zwitterionic complexing agent for targeting AR coatings was obtained. Separately, 4.0 g of perfluorohexylethanol and 1.5 g of succinic anhydride were placed in a dry reaction flask, 20 g of anhydrous tetrahydrofuran was added, followed by 0.1 g of 4-dimethylaminopyridine. The mixture was stirred at 25 °C for 14 hours. After the reaction was complete, the solvent was removed by vacuum distillation to obtain a white solid perfluorohexylethyl succinate. This product was dissolved in 15 g of acetonitrile, and 2.2 g of N,N-dicyclohexylcarbodiimide and 1.3 g of N-hydroxysuccinimide were added. The mixture was stirred and activated at 5 °C in an ice-water bath for 4 hours. The precipitate was removed by filtration, and 3.0 g of N-triethoxysilylpropylethylenediamine and 2.0 g of triethylamine, which had been pre-dissolved in 10 g of acetonitrile, were added to the filtrate. The mixture was stirred at 25 °C for 12 hours. After the reaction was complete, the mixture was filtered, and the filtrate was concentrated under reduced pressure to obtain the crude product. The crude product was purified by silica gel column chromatography, eluted with a gradient of petroleum ether and ethyl acetate to obtain 6.0 g of a colorless, oily, fluorine-affinity surfactant stripper targeting the AF coating. 690 g of deionized water was added to a 2000 mL reactor, the stirring was started and controlled at 200 rpm, the temperature was maintained at 25 °C, and 190 g of triethanolamine was added dropwise at a rate of 4.5 g per minute. After the addition was complete, stirring was continued for 15 minutes.Add 22g of potassium carbonate and 35g of potassium gluconate sequentially, 5 minutes apart, stirring until completely dissolved to form a clear alkaline base solution. Add 310g of deionized water to a 500mL premixing container, start stirring at 300rpm, and slowly add 88g of the prepared multidentate zwitterionic complexing agent for the targeted AR coating, maintaining a temperature of 25℃ and stirring for 45 minutes until completely dissolved. Slowly add 60g of the prepared fluorine-affinity surfactant stripping agent for the targeted AF coating at a rate of 2.2g per minute, continuing stirring at 300rpm for 70 minutes after the addition is complete to obtain a homogeneous premix. Slowly add the premix to the alkaline base solution in the reactor at a rate of 11g per minute, maintaining the reactor temperature at 25℃ during the addition, and continuing stirring at 200rpm for 70 minutes after the addition is complete. Add 55g of ethylene glycol phenyl ether and 18g of polyacrylamide solution sequentially, stirring for 15 minutes after each addition. The system was heated to 39°C at a rate of 1°C per minute and maintained at this temperature while stirring at 150 rpm for 130 minutes for aging. After aging, the system was cooled to 25°C at a rate of 2°C per minute, and the pH was adjusted to 10.6 with a 25% tetramethylammonium hydroxide aqueous solution. Finally, the stripping solution was filtered through a 1μm polypropylene filter bag to obtain a clear and transparent final product.

[0059] Comparative Example 1 The specific implementation method is the same as in Example 1, except that 700g of deionized water is added to the reaction vessel, and 180g of triethanolamine is added dropwise at a rate of 5g per minute. After stirring and dissolving, 20g of potassium carbonate and 30g of potassium gluconate are added sequentially, and the mixture is stirred until an alkaline base solution is formed. Then, 50g of ethylene glycol phenyl ether and 15g of polyacrylamide solution are added sequentially. The system is heated to 38°C for aging and stirred for 120 minutes. After aging, the system is cooled to 25°C, and the pH is adjusted to 10.5 with tetramethylammonium hydroxide solution. The stripping solution is then filtered through a polypropylene filter bag to obtain the final product.

[0060] Comparative Example 2 The specific implementation method is the same as in Example 1, except that: 700g of deionized water is added to the reaction vessel, and 180g of triethanolamine is added dropwise at a rate of 5g per minute. After stirring and dissolving, 20g of potassium carbonate and 30g of potassium gluconate are added sequentially, and the mixture is stirred until an alkaline base solution is formed. In a premixed container with 300g of deionized water pre-added, 85g of disodium EDTA is added and stirred for 40 minutes to dissolve. Then, 58g of sodium dodecyl sulfate is added dropwise at a rate of 2g per minute, and the mixture is stirred for another 60 minutes to obtain a premixed solution. The premixed solution is added dropwise to the alkaline base solution at a rate of 10g per minute, and the mixture is stirred for another 60 minutes. Then, 50g of ethylene glycol phenyl ether and 15g of polyacrylamide solution are added sequentially. The system is heated to 38°C for aging and stirred for 120 minutes. After aging, the system is cooled to 25°C, and the pH is adjusted to 10.5 with tetramethylammonium hydroxide solution. The stripping solution is then filtered through a polypropylene filter bag to obtain the final product.

[0061] Comparative Example 3 The specific implementation method is the same as in Example 1, except that: 700g of deionized water is added to the reaction vessel, and 180g of triethanolamine is added dropwise at a rate of 5g per minute. After stirring and dissolving, 20g of potassium carbonate and 30g of potassium gluconate are added sequentially, and the mixture is stirred until an alkaline base solution is formed. In a premixed container with 300g of deionized water pre-added, 85g of sodium citrate is added and stirred for 40 minutes to dissolve it. Then, 58g of OP-10 emulsifier is added dropwise at a rate of 2g per minute, and the mixture is stirred for another 60 minutes to obtain a premixed solution. The premixed solution is added dropwise to the alkaline base solution at a rate of 10g per minute, and the mixture is stirred for another 60 minutes. Then, 50g of ethylene glycol phenyl ether and 15g of polyacrylamide solution are added sequentially. The system is heated to 38°C for aging and stirred for 120 minutes. After aging, the system is cooled to 25°C, and the pH is adjusted to 10.5 with tetramethylammonium hydroxide solution. The stripping solution is then filtered through a polypropylene filter bag to obtain the final product.

[0062] Performance testing The optical glass AR-AF coating stripping solutions that do not damage ink and glass, prepared in Examples 1-3 and Comparative Examples 1-3 above, were subjected to performance tests according to the following methods: Performance testing was conducted strictly in accordance with optical glass industry standards, and all tests were carried out in a constant temperature and humidity laboratory environment. First, a coating removal efficiency test was performed: a 50mm×50mm×0.7mm soda-lime glass substrate was selected. After precision cleaning, a specific pattern of epoxy resin black ink markings was printed using screen printing. Subsequently, a five-layer SiO2 / TiO2 alternating structure anti-reflective coating was deposited using magnetron sputtering (the thickness of each layer was calibrated using an ellipsometry, and the total thickness was controlled within 300±10nm). Finally, a fluorinated silane-based anti-fingerprint coating was deposited using chemical vapor deposition. During the test, the sample was completely immersed in a polypropylene beaker containing 500 mL of stripping solution and placed in a constant temperature water bath at 60±1℃. Timing started from the moment of immersion, and the sample was removed every minute. After rinsing with deionized water and drying with nitrogen, the coating peeling was visually observed at a 45° angle under a standard D65 light source. At the same time, a contact angle meter was used to monitor the change in surface contact angle (complete peeling was considered when the contact angle dropped from more than 110° initially to about 30° of uncoated glass and there was no rainbow interference on the surface). The time (in minutes) required for complete coating peeling was recorded. If the coating was not completely peeled within 15 minutes, it was recorded as not completely peeled. Substrate damage evaluation was then conducted: the average transmittance of the glass specimens before and after film removal was measured in the wavelength range of 380nm-780nm using a UV-Vis spectrophotometer (equipped with an integrating sphere), and the change was calculated; the arithmetic mean roughness Ra value before and after film removal was measured at 5 different locations randomly selected on the specimen surface using a surface profilometer (probe radius 2μm, pressure 0.5mN), and the average value was used to calculate the change; the surface morphology of the glass was observed under 10,000x magnification using a field emission scanning electron microscope to check for defects such as corrosion pits and cracks. The integrity of the ink was evaluated as follows: First, the integrity of the ink markings before and after stripping was observed visually and under an optical microscope (200x magnification) to check for swelling, peeling, discoloration, or blurred edges. Then, a colorimeter (using the CIE L*a*b* colorimetric system, D65 light source, 10° field of view) was used to select five fixed measurement points in the ink area to measure the color difference ΔE before and after stripping (ΔE=[(ΔL*)²+(Δa)²+(Δb)²]^1 / 2). For solution stability testing, 200mL of stripping solution was placed in a sealed polyethylene bottle and aged in a 40±1℃ constant temperature oven for 7 days. After being removed and brought to room temperature, the solution was observed for precipitation or stratification. The stripping efficiency was then tested again using the same method. Environmental friendliness and safety were assessed by measuring the initial pH value of the stripping solution with a precision pH meter and evaluating its environmental friendliness (including COD value, heavy metal content, and preliminary assessment of biodegradability) according to laboratory wastewater treatment standards. All tests were performed in triplicate, and the average value was taken as the final result.

[0063] Performance test results: Table 1: Performance test results of each embodiment and comparative example

[0064] As shown in Table 1, the test results fully demonstrate that Examples 1-3 of the present invention successfully solved the core technical problem that existing stripping solutions inevitably corrode the glass substrate and damage the printed ink markings on the surface when removing the AR-AF coating from optical glass. Examples 1-3 exhibit excellent comprehensive performance: the stripping time is controlled within 10 minutes, the transmittance change is less than 0.7%, the surface roughness change is no more than 0.3 nm, SEM observation shows that the glass surface is intact, the ink appearance has no change, and the color difference ΔE value is less than 0.5. This indicates that the synergistic effect of the novel multidentate zwitterionic complexing agent targeting the AR coating and the fluorine-affinity surfactant stripping agent targeting the AF coating can efficiently and selectively remove the coating while perfectly protecting the substrate and ink. In contrast, Comparative Example 1, lacking both specific components, was almost unable to effectively remove the film and caused severe corrosion to the glass (transmittance decreased by 4.2%, roughness increased by 15.7 nm), with the ink completely dissolved, proving that conventional alkaline systems cannot solve this technical problem. Comparative Example 2, using the conventional combination of disodium EDTA and sodium dodecyl sulfate, although showing some film removal effect (35 minutes), still resulted in a 1.8% decrease in glass transmittance and a 5.2 nm increase in roughness, with slight swelling and significant color difference in the ink (ΔE=3.5), indicating that ordinary complexing agents and surfactants lack the necessary selectivity and protection. Comparative Example 3, using sodium citrate and OP-10 emulsifier, had even more serious problems, with low film removal efficiency (45 minutes), significant substrate corrosion (transmittance decreased by 2.5%, roughness increased by 8.1 nm) and ink damage (partial peeling, ΔE=5.2), further highlighting the limitations of conventional raw materials. All comparative solutions exhibited poor stability, becoming turbid, separating, or precipitating after aging, and showing a significant decrease in stripping efficiency. In contrast, the stripping solutions from Examples 1-3 remained clear and transparent, maintaining an efficiency retention rate of over 97%, and demonstrating superior environmental friendliness. In summary, the core advantages of Examples 1-3 are entirely attributable to two newly designed modified compounds. Through precise molecular design, these compounds achieve efficient and selective decomposition of the AR-AF coating while exhibiting extremely weak interactions with the glass substrate and ink. This fundamentally overcomes the bottleneck of traditional technologies that cannot simultaneously achieve efficient stripping and perfect protection, providing an unprecedented solution for this field.

[0065] The embodiments described above are merely examples of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention.

Claims

1. A method for preparing an optical glass AR-AF coating stripping solution that does not damage the ink and glass, characterized in that the steps include... include: S1. Add deionized water to the reaction vessel, add triethanolamine dropwise and stir to dissolve, then add potassium carbonate and potassium gluconate in sequence and stir until an alkaline base solution is formed. S2. In a premixed container with pre-added deionized water, add a multidentate zwitterionic complexing agent for the AR coating and stir to dissolve it; then add a fluorine-affinity surfactant stripping agent for the AF coating dropwise and continue stirring to obtain a premixed solution; add the premixed solution dropwise to an alkaline base solution and continue stirring; then add ethylene glycol phenyl ether and polyacrylamide solution in sequence. S3. Heat the system to 35-40℃ for maturation and stir. After maturation, cool to room temperature and adjust the pH to 10.3-10.7 using tetramethylammonium hydroxide or citric acid solution as an adjuster. Filter the membrane stripping solution through a polypropylene filter bag.

2. The method for preparing the optical glass AR-AF coating stripping solution that does not damage the ink and glass according to claim 1, characterized in that, In step S1, the triethanolamine is added dropwise over a period of 10-15 minutes.

3. The method for preparing the optical glass AR-AF coating stripping solution that does not damage the ink and glass according to claim 1, characterized in that, In step S2, the stirring time for dissolution is 30-45 minutes.

4. The method for preparing the optical glass AR-AF coating stripping solution that does not damage the ink and glass according to claim 1, characterized in that, The preparation method of the multidentate zwitterionic complexing agent for the targeted AR coating includes: A1. Dissolve 2,4-dibromo-6-((bis(2-((tert-butoxycarbonyl)amino)ethyl)amino)methyl)phenol in anhydrous N,N-dimethylformamide, add sodium hydride under argon protection and ice-water bath cooling, and stir the reaction; then add a premixed suspension of 3-chloro-N,N-dimethylpropylamine hydrochloride and triethylamine, and raise the temperature to room temperature for reaction; A2. After the reaction was complete, the mixture was poured into ice water and extracted with ethyl acetate. The organic phase was washed with saturated brine, dried over anhydrous sodium sulfate, and distilled under reduced pressure to obtain the crude product. The crude product was dissolved in dichloromethane, and trifluoroacetic acid was added. The mixture was stirred at room temperature. After the reaction was complete, the mixture was distilled under reduced pressure to obtain a viscous oil. The viscous oil was dissolved in a methanol / water mixture, and tert-butyl bromoacetate and N,N-diisopropylethylamine were added. The mixture was reacted at 58-62°C. After the reaction was complete, the residue was distilled under reduced pressure and dissolved in dichloromethane. Trifluoroacetic acid was added again, and the mixture was reacted at room temperature. The residue was then dissolved in deionized water and purified by passing it through a strongly acidic cation exchange resin column.

5. The method for preparing the optical glass AR-AF coating stripping solution that does not damage the ink and glass according to claim 4, characterized in that, In step A1, the stirring reaction time is 30-40 min; the reaction time to room temperature is 12-14 h.

6. The method for preparing the optical glass AR-AF coating stripping solution that does not damage the ink and glass according to claim 4, characterized in that, In step A2, the reaction time is 4-6 hours with stirring at room temperature.

7. The method for preparing the optical glass AR-AF coating stripping solution that does not damage the ink and glass according to claim 1, characterized in that, The preparation method of the fluorine-affinity surfactant stripper for the targeted AF coating includes: B1. Dissolve perfluorohexylethanol and succinic anhydride in anhydrous tetrahydrofuran, add 4-dimethylaminopyridine, and stir the reaction at room temperature; after the reaction is complete, evaporate under reduced pressure to obtain perfluorohexylethylsuccinic acid monoester. B2. Perfluorohexyl ethyl succinate monoester was dissolved in acetonitrile, and N,N'-dicyclohexylcarbodiimide and N-hydroxysuccinimide were added. The mixture was activated in an ice bath and filtered. N-(3-triethoxysilylpropyl)ethylenediamine and triethylamine dissolved in acetonitrile were added to the filtrate and the mixture was reacted at room temperature. After the reaction was completed, the mixture was filtered, and the filtrate was concentrated under reduced pressure to obtain the crude product. The crude product was purified by silica gel column chromatography.

8. The method for preparing the optical glass AR-AF coating stripping solution that does not damage the ink and glass according to claim 7, characterized in that, In step B1, the reaction is stirred at room temperature for 12-14 hours.

9. The method for preparing the optical glass AR-AF coating stripping solution that does not damage the ink and glass according to claim 7, characterized in that, In step B2, the activation time under ice bath is 2-4 hours.

10. A stripping solution for optical glass AR-AF coating that does not damage ink or glass, characterized in that, The optical glass AR-AF coating stripping solution that does not damage ink and glass is prepared by the method described in any one of claims 1-9.

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