A method for producing an environmentally friendly, water-based silver powder paint with an electroplating silver effect.

Abstract

This invention relates to the field of water-based silver powder paint, specifically to an environmentally friendly method for producing a water-based silver powder paint with an electroplating silver effect. This method solves the problem that existing water-based silver powder paints cannot simultaneously achieve an electroplated silver appearance, stable storage, high hardness, and excellent corrosion resistance. The method involves first adding a dispersant and passivating agent to deionized water and stirring, then adding a double-coated floating aluminum silver paste and stirring, followed by adding a directional agent and stirring, then adding a water-based epoxy-acrylic composite resin and stirring, and sequentially adding dodecyl alcohol ester, fluorescent whitening agent solution, leveling agent, silicone defoamer, and anti-corrosion and anti-mildew agent and stirring, then adding triethanolamine to adjust the pH value, stirring, and filtering to obtain component A. Before use, components A and B are mixed in a specific mass ratio and stirred to obtain the water-based silver powder paint. This water-based silver powder paint possesses a high mirror-like metallic texture, high hardness, excellent adhesion, and salt spray resistance, while also being environmentally friendly and low in VOCs.

Description

Technical Field

[0001] This invention relates to the field of water-based silver powder paint, and more specifically to a method for producing an environmentally friendly water-based silver powder paint with an electroplating silver effect. Background Technology

[0002] With increasingly stringent global environmental regulations and tightening restrictions on volatile organic compound (VOC) emissions, water-based coatings, with their advantages of low pollution and low toxicity, are gradually replacing traditional oil-based coatings and becoming the mainstream in the industrial coating field. Water-based metallic paint, as a coating with a unique metallic luster and decorative effect, is widely used in automotive parts, appliance casings, hardware tools, architectural decoration, and other fields, and market demand continues to grow.

[0003] However, existing water-based silver powder paint technology still has the following core problems that urgently need to be solved: poor appearance, making it difficult to achieve the texture of electroplated silver; extremely poor storage stability, posing serious safety hazards; insufficient mechanical properties of the paint film, making it easy to scratch and damage; poor corrosion resistance, resulting in a short service life.

[0004] Currently, existing technologies cannot simultaneously achieve excellent appearance, storage stability, mechanical properties, and corrosion resistance, limiting the further application of water-based silver powder paints in high-end industrial coating fields. Therefore, developing an environmentally friendly water-based silver powder paint that combines electroplating silver effects, ultra-long shelf life, high hardness, and excellent corrosion resistance is of significant practical importance. Summary of the Invention

[0005] In order to overcome the above-mentioned technical problems, the purpose of this invention is to provide an environmentally friendly method for producing water-based silver powder paint with an electroplating silver effect.

[0006] The objective of this invention can be achieved through the following technical solutions: This application provides a method for preparing an environmentally friendly water-based silver powder paint with an electroplating silver effect, comprising the following steps: Step 1: Weigh out the following components by weight: 15-25 parts dispersant, 11-18 parts passivating agent, 220-366 parts deionized water, 130-216 parts double-coated floating aluminum silver paste, 10-15 parts orientation agent, 420-700 parts waterborne epoxy-acrylic composite resin, 15-25 parts dodecyl alcohol ester, 60-100 parts fluorescent whitening agent solution, 12-20 parts leveling agent, 0.3-0.5 parts silicone defoamer, and 0.3-0.5 parts preservative and mildew inhibitor. Set aside for later use. Step 2: First, add the dispersant and passivating agent to deionized water and stir for 5-7 minutes at a stirring speed of 480-500 rpm. Then, add the double-coated floating aluminum silver paste and stir for 15-17 minutes at a stirring speed of 780-800 rpm. After that, reduce the stirring speed to 480-500 rpm, add the orientation agent, and stir for 5-7 minutes. Then, add the waterborne epoxy-acrylic composite resin and stir for 10-12 minutes. Next, add the dodecyl alcohol ester, fluorescent whitening agent solution, leveling agent, silicone defoamer, and preservative and mildew inhibitor in sequence. Increase the stirring speed to 900-1000 rpm and stir for 20-22 minutes. Reduce the stirring speed to 300 rpm and add triethanolamine dropwise until the pH value is 6.5-6.8. Stir for 5-7 minutes and then filter through a 200-mesh filter to obtain component A. Step 3: Before use, mix components A and B at a mass ratio of 9:1 and stir for 8-10 minutes at a stirring speed of 300-400 r / min to obtain water-based silver powder paint.

[0007] In a preferred embodiment of the present invention, the fluorescent whitening agent solution in step two is a solution of 2,5-bis(5-tert-butyl-2-benzoxazolyl)thiophene and propylene glycol methyl ether mixed in a ratio of 0.4g:100g.

[0008] In a preferred embodiment of the present invention, the passivating agent in step two is Tech-8892; the dispersant is DISPERBYK-192; the orienting agent is Disparlon 6900-20X; the leveling agent is TEGO Glide 410; the silicone defoamer is Tego Foamex 810; and the preservative and mildew inhibitor is BIT-20.

[0009] In a preferred embodiment of the present invention, component B in step three is a water-based curing agent, model Bayhydur. BL 5140.

[0010] The waterborne epoxy-acrylic composite resin is prepared by the following steps: Step a1: Protocatechuic aldehyde, erythritol, p-toluenesulfonic acid monohydrate, anhydrous N,N-dimethylformamide, and petroleum ether were added to a single-necked round-bottom flask equipped with a magnetic stir bar, a water separator, and a reflux condenser. Nitrogen gas was introduced for protection, and the mixture was stirred for 24 hours at a temperature of 85-90℃ and a stirring rate of 300-400 r / min. After the reaction was completed, the mixture was allowed to cool naturally to room temperature. The reaction solution was poured into an aqueous sodium bicarbonate solution while stirring, and a precipitate was formed. The precipitate was collected by suction filtration using a Buchner funnel and washed with deionized water until the pH of the filtrate was neutral. The filter cake was placed in a vacuum drying oven and dried at a temperature of 55-60℃ for 6-6.2 hours to obtain the dicyclic diacetal tetrahydroxy monomer.

[0011] Step a2: Add the bicyclic diacetal tetrahydroxy monomer, anhydrous ethanol, and deionized water to a single-necked round-bottom flask equipped with a spherical condenser. Purge with nitrogen for protection and stir at a stirring rate of 300-400 r / min for 15-17 min. Then, raise the water bath temperature to 75℃ and stir for 20-22 min. Add activated carbon and continue stirring for 30-35 min. Filter while hot, allow the filtrate to cool to room temperature, and then transfer it to a 4℃ refrigerator for 12 h. Collect the precipitate by vacuum filtration, wash twice with anhydrous ethanol, and then place it in a vacuum drying oven at a temperature of 55-60℃ for 6-6.2 h to obtain the purified bicyclic diacetal tetrahydroxy monomer. Step a3: Add the purified bicyclic diacetal tetrahydroxy monomer, epichlorohydrin, and tetrabutylammonium bromide to the reaction vessel, purge with nitrogen for protection, and stir the reaction at 78-80℃ and a stirring rate of 300-400 r / min for 3.5-3.8 h. Then allow it to cool naturally to room temperature. Next, add sodium hydroxide aqueous solution dropwise while stirring, controlling the addition time to be 70-80 min. After the addition is complete, continue stirring the reaction for 4-4.5 h. Then filter the mixture. The solution was diluted with dichloromethane, washed 5 times with deionized water and 3 times with saturated saline solution. After each washing, the solution was allowed to stand for 30 minutes to separate into layers. The organic phase was collected, dried with anhydrous magnesium sulfate for 40-45 minutes, filtered, and the filtrate was transferred to a rotary evaporator and evaporated at a temperature of 45-50℃ and a pressure of -0.095MPa. The solution was then placed in a vacuum drying oven and dried at a temperature of 55-60℃ for 5-5.2 hours to obtain glycidyl ether epoxy monomer.

[0012] Step a4: Add propylene glycol methyl ether to a four-necked flask, purge with nitrogen for protection, heat to 75-78℃, and stir at 300-400 rpm. Mix methyl methacrylate, trifluoroethyl methacrylate, butyl acrylate, acrylic acid, hydroxyethyl acrylate, and 2 / 3 of benzoyl peroxide in a constant-pressure dropping funnel, controlling the dropping time for 3-3.2 hours. When half of the mixture has been added, add the remaining 1 / 3 of the benzoyl peroxide. After the addition is complete, continue the reaction for 2-2.2 hours, cool to 70℃, then add triethylamine and stir for 5-7 minutes. Add glycidyl ether epoxy monomer dropwise, controlling the dropwise addition. The reaction time is 1.3-1.5 hours, and the reaction continues for 4-4.2 hours. After the reaction is completed, the temperature is lowered to 50°C, the stirring speed is increased to 1500 r / min, and AMP-95 multifunctional additive is added dropwise to adjust the pH value to 5-6. Then, 1 / 3 of the deionized water is added dropwise at a rate of 1 g / min, and the dropping speed is adjusted to 2 g / min. The remaining 2 / 3 of the deionized water is added dropwise, and the dropping time is controlled at 50-60 minutes. Then, silicone defoamer and preservative and mildew inhibitor are added, and the mixture is stirred for 30-35 minutes. The mixture is then filtered through a 200-mesh nylon filter to obtain waterborne epoxy-acrylic composite resin.

[0013] In a preferred embodiment of the present invention, the ratio of protocatechuic aldehyde, erythritol, p-toluenesulfonic acid monohydrate, anhydrous N,N-dimethylformamide, petroleum ether, and sodium bicarbonate aqueous solution in step a1 is 0.2-0.4 mol: 0.1-0.2 mol: 0.0042-0.0084 mol: 30-60 mL: 60-120 mL: 500-1000 mL.

[0014] In a preferred embodiment of the present invention, the sodium bicarbonate aqueous solution in step a1 has a mass fraction of 3%.

[0015] In a preferred embodiment of the present invention, the ratio of the amount of the bicyclic diacetal tetrahydroxy monomer, anhydrous ethanol, deionized water and activated carbon in step a2 is 10-20g: 40-80mL: 10-20mL: 1-2g.

[0016] In a preferred embodiment of the present invention, the particle size of the activated carbon in step a2 is 60-80 μm.

[0017] In a preferred embodiment of the present invention, the ratio of purified bicyclic diacetal tetrahydroxy monomer, epichlorohydrin, tetrabutylammonium bromide and sodium hydroxide aqueous solution in step a3 is 10-20g: 51-102g: 1-2g: 11-22g.

[0018] In a preferred embodiment of the present invention, the sodium hydroxide aqueous solution in step a3 has a mass fraction of 40%.

[0019] In a preferred embodiment of the present invention, the ratio of the following components in step a4 is as follows: propylene glycol methyl ether, methyl methacrylate, trifluoroethyl methacrylate, butyl acrylate, acrylic acid, hydroxyethyl acrylate, benzoyl peroxide, triethylamine, glycidyl ether epoxy monomer, deionized water, silicone defoamer, and preservative and mildew inhibitor.

[0020] In a preferred embodiment of the present invention, the silicone defoamer in step a4 is TegoFoamex 810.

[0021] In a preferred embodiment of the present invention, the anti-corrosion and anti-mildew agent in step a4 is of type BIT-20.

[0022] The double-coated floating aluminum silver paste is prepared by the following steps: Step b1: Add oily aluminum silver paste and 1 / 2 isopropanol to a beaker and stir for 15-20 min at a stirring rate of 280-300 r / min. Then, ultrasonically disperse for 15-17 min at an ultrasonic power of 200-300 W. Filter and wash the filter cake three times with isopropanol. Disperse the filter cake in 1 / 2 isopropanol and transfer it to a four-necked flask. Purge with nitrogen and maintain the temperature at 40-45℃ and a stirring rate of 280-300 r / min. Adjust the pH to 8.5-8.7 with ammonia. Then, add tetraethyl orthosilicate-isopropanol solution dropwise while stirring, controlling the dropwise addition time to 4-4.2 h. After the dropwise addition is complete, continue to keep the reaction at the temperature for 6-6.2 h. Then, cool naturally to room temperature and age for 12-13 h. Filter and wash the filter cake three times with anhydrous ethanol to obtain a silica-coated aluminum silver paste wet cake. Step b2: Disperse the silica-coated aluminum silver paste wet cake in isopropanol, transfer it to a four-necked flask, purge with nitrogen, and add silane coupling agent solution dropwise while stirring at a temperature of 45-50℃ and a stirring rate of 280-300 r / min, controlling the addition time to 60-70 min. After the addition is complete, continue the reaction for 3.5-4 h, filter, wash the filter cake twice with anhydrous ethanol, disperse the filter cake in propylene glycol methyl ether, stir for 30 min under nitrogen protection, and pass through a 200-mesh sieve to obtain double-coated floating aluminum silver paste.

[0023] In a preferred embodiment of the present invention, the ratio of the amount of oily aluminum silver paste, isopropanol and tetraethyl orthosilicate-isopropanol solution in step b1 is 100-120g: 700-840mL: 50-60mL.

[0024] In a preferred embodiment of the present invention, the tetraethyl orthosilicate-isopropanol solution in step b1 is a solution in which tetraethyl orthosilicate and isopropanol are mixed in a ratio of 15g:50mL.

[0025] In a preferred embodiment of the present invention, the particle size of the oily aluminum silver paste in step b1 is 15-20 μm.

[0026] In a preferred embodiment of the present invention, the ratio of the amount of silica-coated aluminum silver paste wet cake, isopropanol, silane coupling agent solution and propylene glycol methyl ether in step b2 is 100-120g: 300-360mL: 20-24mL: 110-160g.

[0027] In a preferred embodiment of the present invention, the silane coupling agent solution in step b2 is a mixture of γ-methacryloyloxypropyltrimethoxysilane and isopropanol in a ratio of 2g:20mL.

[0028] The beneficial effects of this invention are: This invention discloses an environmentally friendly water-based silver powder paint with an electroplating silver effect. The method involves first adding a dispersant and passivating agent to deionized water and stirring; then adding a double-coated floating aluminum silver paste and stirring; subsequently, reducing the stirring speed; adding a directional agent and stirring; then adding a water-based epoxy-acrylic composite resin and stirring; and then sequentially adding dodecyl alcohol ester, fluorescent whitening agent solution, leveling agent, silicone defoamer, and preservative and antifungal agent and stirring; finally, adding triethanolamine dropwise to adjust the pH value; stirring; and then filtering to obtain component A. Before use, components A and B are mixed and stirred according to the mass ratio to obtain water-based silver powder paint. The water-based epoxy-acrylic composite resin possesses a rigid skeleton, high cross-linking degree, and excellent weather resistance and corrosion resistance. It can guide the aluminum silver paste to uniformly and orientally distribute, presenting a realistic electroplating mirror effect, and significantly improve the adhesion, corrosion resistance, and storage stability of the paint film, perfectly adapting to high-performance environmentally friendly water-based silver powder paint systems. The double-coated floating aluminum silver paste relies on the inner layer of silica to block water-phase corrosion and the outer layer of silane to improve compatibility with the resin, thus solving the problems of water-based silver powder... This invention addresses the problem of hydrogen evolution and blackening during paint storage, improves storage stability, maintains the floating orientation of aluminum flakes, imparts an excellent mirror-like metallic texture and electroplated silver effect to the paint film, and enhances the paint film's resistance to salt spray, weathering, and application dispersion. Through the synergistic effect of water-based epoxy-acrylic composite resin and double-coated floating aluminum silver paste, the prepared water-based silver powder paint combines a high mirror-like metallic texture and realistic appearance, while also possessing high hardness, excellent adhesion, and salt spray corrosion resistance. Furthermore, it is environmentally friendly with low VOCs and can be widely used in high-end industrial coating fields.

[0029] In the preparation of water-based silver powder paint, a water-based epoxy-acrylic composite resin is first prepared. Initially, protocatechuic aldehyde and erythritol undergo an intramolecular cyclization acetal reaction under acidic conditions to form a rigid bicyclic diacetal structure, retaining four hydroxyl groups. This structure combines a rigid framework with hydrophilic groups, providing reaction sites for subsequent epoxy modification. Activated carbon decolorization and low-temperature crystallization remove byproduct quinone impurities, preventing color darkening in subsequent reactions and ensuring the high whiteness and metallic luster of the silver powder paint. Then, the tetrahydroxy monomer of the bicyclic diacetal reacts with epichlorohydrin in a two-step reaction catalyzed by tetrabutylammonium bromide. First, the hydroxyl groups attack the epoxy ring of epichlorohydrin, undergoing a ring-opening reaction to generate a chlorohydrin intermediate. Subsequently, under the action of sodium hydroxide aqueous solution, the chlorohydrin intermediate undergoes dechlorination. Hydrogen peroxide undergoes a ring-closure reaction to generate a tetrafunctional epoxy monomer with four glycidyl ether groups. Then, under the initiator benzoyl peroxide, acrylic monomers such as methyl methacrylate and butyl acrylate undergo free radical polymerization to form an acrylic prepolymer backbone with carboxyl and hydroxyl side chains. Methyl methacrylate provides hardness and weather resistance, butyl acrylate provides flexibility, acrylic acid introduces carboxyl groups, providing reaction sites for subsequent water-based conversion and epoxy grafting, and hydroxyethyl acrylate provides hydroxyl groups to enhance crosslinking density. After cooling, triethylamine is added as a catalyst to promote a ring-opening esterification reaction between the carboxyl groups of the prepolymer side chains and the epoxy groups in the glycidyl ether epoxy monomers, chemically grafting the rigid bicyclic diacetal epoxy structure onto the acrylic backbone, thereby constructing a... The epoxy-acrylic hybrid molecular backbone is neutralized by AMP-95 multifunctional additives to form hydrophilic carboxylates on the main chain, imparting hydrophilicity to the polymer molecular chains. Then, through high-speed shearing and gradient hydration, reverse emulsification occurs, causing the hydrophobic polymer segments to self-assemble and disperse in water, ultimately forming a structurally stable waterborne epoxy-acrylic composite resin emulsion. The waterborne epoxy-acrylic composite resin incorporates a rigid bicyclic diacetal structure formed by the condensation of protocatechuic aldehyde and erythritol. This structure provides strong molecular chain rigidity and uniform film shrinkage, guiding the floating aluminum silver paste layers to arrange in a regular, parallel orientation on the paint film surface. This significantly enhances the metallic texture and mirror gloss of the silver paint, presenting an appearance similar to electroplated silver, while also effectively improving the film hardness, scratch resistance, and structure. The coating exhibits excellent adhesion to metal substrates through ring-opening grafting of glycidyl ether epoxy monomers and acrylic prepolymer carboxyl groups. This results in superior adhesion and, thanks to the high-purity monomers and the dense shielding effect of the epoxy, effectively prevents the penetration of water, oxygen, and corrosive media, enhancing the coating's resistance to salt spray, water, acids, alkalis, and solvents. The introduction of trifluoroethyl methacrylate utilizes the low surface energy of fluorine to impart dust and stain resistance, while also providing excellent resistance to UV and thermo-oxidative aging. Outdoor use is less prone to gloss loss, discoloration, chalking, and aging. The resin side chains retain active hydroxyl groups, allowing cross-linking with water-based curing agents to form a dense three-dimensional network, further enhancing the coating's mechanical strength, abrasion resistance, and weather resistance. Furthermore, the entire formulation is water-based, environmentally friendly, and low in VOCs, meeting green coating requirements.

[0030] In the preparation of water-based silver powder paint, a double-coated floating aluminum silver paste was first prepared. Firstly, the oil-based aluminum silver paste was dispersed with isopropanol and ultrasonically broken up agglomerated particles to remove surface oil and additive impurities. Then, under weakly alkaline conditions, tetraethyl orthosilicate underwent a hydrolysis-condensation reaction, uniformly depositing a dense silica inorganic inner coating film on the flake surface of the aluminum silver paste. This film isolates the aluminum powder from direct contact with water, acids, and alkalis, inhibiting hydrogen evolution corrosion and oxidative discoloration. Subsequently, a silane coupling agent was used for secondary modification. The siloxane groups of the silane coupling agent condensed and bonded with the hydroxyl groups on the silica surface, and the organic functional segments were arranged outwards to form an organosilane outer coating, dispersed in propylene glycol methyl ether. This yielded a double-coated floating aluminum silver paste with an inner silica layer and an outer silane coupling agent modified layer. The dense inner layer of silica effectively blocks moisture and acid / alkali corrosion, significantly improving the storage stability and shelf life of water-based silver powder paint. The outer layer of silane coupling agent significantly improves the wetting compatibility and interfacial bonding between aluminum silver paste and water-based epoxy-acrylic composite resin, avoiding defects such as floating, blooming, and delamination in the paint film. The preparation process uses gentle stirring and low-power ultrasonic dispersion to fully preserve the original flake morphology and floating properties of the aluminum flakes. Combined with the resin's orientation effect, the aluminum flakes are arranged in a regular and parallel manner, giving the paint film a strong mirror metallic texture and a realistic electroplated silver effect, effectively improving the gloss and whiteness of the paint film. At the same time, the double coating has excellent passivation protection capabilities, significantly enhancing the paint film's resistance to acids and alkalis, salt spray, and weathering, meeting the requirements for high-corrosion-resistant outdoor coatings. Detailed Implementation

[0031] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0032] Example 1: This embodiment describes a method for producing an environmentally friendly, water-based silver powder paint with an electroplating silver effect, comprising the following steps: Step S1: 0.2 mol protocatechuic aldehyde, 0.1 mol erythritol, 0.0042 mol p-toluenesulfonic acid monohydrate, 30 mL anhydrous N,N-dimethylformamide, and 60 mL petroleum ether were added to a single-necked round-bottom flask equipped with a magnetic stir bar, a water separator, and a reflux condenser. Nitrogen gas was introduced for protection, and the mixture was stirred at 85 °C and a stirring rate of 300 r / min for 24 h. After the reaction was completed, the mixture was allowed to cool naturally to room temperature. The reaction solution was poured into 500 mL of sodium bicarbonate aqueous solution (sodium bicarbonate aqueous solution mass fraction was 3%) while stirring. A precipitate was formed and collected by suction filtration using a Buchner funnel. The precipitate was washed with deionized water until the pH of the filtrate was neutral. The filter cake was placed in a vacuum drying oven and dried at 55 °C for 6 h to obtain the dicyclic diacetal tetrahydroxy monomer. Step S2: Add 10g of bicyclic diacetal tetrahydroxy monomer, 40mL of anhydrous ethanol and 10mL of deionized water to a single-necked round-bottom flask equipped with a spherical condenser. Purge with nitrogen for protection and stir at 300r / min for 15min. Then raise the water bath temperature to 75℃ and stir for 20min. Add 1g of activated carbon (60μm particle size) and continue stirring for 30min. Filter while hot (temperature > 60℃). Allow the filtrate to cool to room temperature and then transfer it to a 4℃ refrigerator for 12h. Collect the precipitate by vacuum filtration, wash twice with anhydrous ethanol, and then place it in a vacuum drying oven at 55℃ for 6h to obtain purified bicyclic diacetal tetrahydroxy monomer. Step S3: 10g of purified bicyclic diacetal tetrahydroxy monomer, 51g of epichlorohydrin and 1g of tetrabutylammonium bromide were added to the reaction vessel, and nitrogen gas was introduced for protection. The reaction was stirred at 78℃ and 300r / min for 3.5h. After that, it was naturally cooled to room temperature. Then, 11g of sodium hydroxide aqueous solution (40% by mass) was added dropwise while stirring, and the addition time was controlled at 70min. After the addition was completed, the reaction was stirred for another 4h. After that, the mixture was filtered, and the filtrate was diluted with dichloromethane. It was washed 5 times with deionized water and 3 times with saturated brine. After each washing, the mixture was allowed to stand for 30min to separate into layers. The organic phase was collected, dried with anhydrous magnesium sulfate for 40min, filtered, and the filtrate was transferred to a rotary evaporator. It was rotary evaporated at 45℃ and -0.095MPa. After that, it was placed in a vacuum drying oven and dried at 55℃ for 5h to obtain glycidyl ether epoxy monomer. Step S4: Add 30g of propylene glycol methyl ether to a four-necked flask, purge with nitrogen for protection, heat to 75°C, and stir at 300 rpm. Mix 55g of methyl methacrylate, 18g of trifluoroethyl methacrylate, 40g of butyl acrylate, 12g of acrylic acid, 7g of hydroxyethyl acrylate, and 1.4g of benzoyl peroxide in a constant-pressure dropping funnel, controlling the dropping time to 3 hours. When half of the mixture has been added, add 0.7g of benzoyl peroxide. After the addition is complete, continue the reaction for 2 hours, cool to 70°C, and then add 0.8g of triethylamine. Stir for 5 hours. Add 40g of glycidyl ether epoxy monomer dropwise over a time of 1.3 hours, and continue the reaction for 4 hours. After the reaction is complete, cool the mixture to 50°C, increase the stirring speed to 1500 r / min, and add AMP-95 multifunctional additive to adjust the pH to 5. Then, add 140g of deionized water dropwise at a rate of 1g / min, then adjust the dropping rate to 2g / min and continue adding 70g of deionized water dropwise over a time of 50 minutes. After that, add 0.50g of silicone defoamer (TegoFoamex 810) and 0.3g of preservative and mildew inhibitor (BIT-20), and continue stirring for 30 minutes. Filter the mixture through a 200-mesh nylon filter to obtain the waterborne epoxy-acrylic composite resin. Step S5: Add 100g of oily aluminum silver paste (particle size of 15μm) and 350mL of isopropanol to a beaker. Stir for 15min at a stirring rate of 280r / min, then ultrasonically disperse for 17min at an ultrasonic power of 200W. Filter, wash the filter cake three times with isopropanol, disperse the filter cake in 350mL of isopropanol, transfer to a four-necked flask, purge with nitrogen for protection, and maintain at 40℃ and a stirring rate of 280r. Under the condition of / min, the pH was adjusted to 8.5 with ammonia water, and then 50 mL of tetraethyl orthosilicate-isopropanol solution (tetraethyl orthosilicate-isopropanol solution is a solution of tetraethyl orthosilicate and isopropanol mixed in a ratio of 15 g: 50 mL) was added dropwise while stirring. The dropwise addition time was controlled at 4 h. After the addition was completed, the reaction was kept at the temperature for 6 h, then naturally cooled to room temperature and aged for 12 h. The mixture was then filtered and the filter cake was washed 3 times with anhydrous ethanol to obtain a silica-coated aluminum silver paste wet cake. Step S6: Disperse 100g of silica-coated aluminum silver paste wet cake in 300mL of isopropanol, transfer it to a four-necked flask, purge with nitrogen, and under conditions of 45℃ and stirring speed of 280r / min, add 20mL of silane coupling agent solution (the silane coupling agent solution is a mixture of γ-methacryloxypropyltrimethoxysilane and isopropanol in a ratio of 2g:20mL) dropwise while stirring. Control the dropping time to 60min. After the dropping is completed, continue the reaction for 3.5h, filter, wash the filter cake twice with anhydrous ethanol, disperse the filter cake in 110g of propylene glycol methyl ether, stir for 30min under nitrogen protection, and pass through a 200-mesh sieve to obtain double-coated floating aluminum silver paste. Step S7: Weigh out 15 parts of dispersant, 11 parts of passivating agent, 220 parts of deionized water, 130 parts of double-coated floating aluminum silver paste, 10 parts of orientation agent, 420 parts of waterborne epoxy-acrylic composite resin, 15 parts of dodecyl alcohol ester, 60 parts of fluorescent whitening agent solution, 12 parts of leveling agent, 0.3 parts of silicone defoamer, and 0.3 parts of preservative and mildew inhibitor according to the following weight proportions, and set aside for later use; Step S8: First, add the dispersant (DISPERBYK-192) and passivator (Tech-8892) to deionized water and stir for 5 minutes at a stirring speed of 480 rpm. Then, add the double-coated floating aluminum silver paste and stir for 15 minutes at a stirring speed of 780 rpm. After that, reduce the stirring speed to 480 rpm and add the orientation agent (Disparlon 6900-20X). Stir for 5 minutes, then add the waterborne epoxy-acrylic composite resin and stir for 10 minutes. Next, add the dodecyl alcohol ester, the fluorescent whitening agent solution (a solution of 2,5-bis(5-tert-butyl-2-benzoxazolyl)thiophene and propylene glycol methyl ether mixed at a ratio of 0.4 g: 100 g), and the leveling agent (TEGO Glide). 410), silicone defoamer (model Tego Foamex 810) and preservative and mildew inhibitor (model BIT-20), increase the stirring speed to 900 r / min, stir for 20 min, reduce the stirring speed to 300 r / min, add triethanolamine dropwise until the pH value is 6.5, stir for 5 min, and then filter through a 200 mesh filter to obtain component A; Step S9: Before use, mix component A and component B (component B is a water-based curing agent, model Bayhydur). Mix BL 5140 and BL 5140 at a mass ratio of 9:1 and stir for 8 minutes at a stirring speed of 300 r / min to obtain water-based silver powder paint.

[0033] Example 2: This embodiment describes a method for producing an environmentally friendly, water-based silver powder paint with an electroplating silver effect, comprising the following steps: Step S1: 0.3 mol protocatechuic aldehyde, 0.15 mol erythritol, 0.0063 mol p-toluenesulfonic acid monohydrate, 45 mL anhydrous N,N-dimethylformamide, and 90 mL petroleum ether were added to a single-necked round-bottom flask equipped with a magnetic stir bar, a water separator, and a reflux condenser. Nitrogen gas was introduced for protection, and the mixture was stirred at 87 °C and a stirring rate of 350 r / min for 24 h. After the reaction was completed, the mixture was allowed to cool naturally to room temperature. The reaction solution was poured into 750 mL of sodium bicarbonate aqueous solution (sodium bicarbonate aqueous solution mass fraction was 3%) while stirring. A precipitate was formed and collected by suction filtration using a Buchner funnel. The precipitate was washed with deionized water until the pH of the filtrate was neutral. The filter cake was placed in a vacuum drying oven and dried at 57 °C for 6.1 h to obtain the dicyclic diacetal tetrahydroxy monomer. Step S2: Add 15g of bicyclic diacetal tetrahydroxy monomer, 60mL of anhydrous ethanol and 15mL of deionized water to a single-necked round-bottom flask equipped with a spherical condenser. Purge with nitrogen for protection and stir at 350r / min for 16min. Then raise the water bath temperature to 75℃ and stir for 21min. Add 1.5g of activated carbon (70μm particle size) and continue stirring for 33min. Filter while hot (temperature >60℃). Allow the filtrate to cool to room temperature and then transfer it to a 4℃ refrigerator for 12h. Collect the precipitate by vacuum filtration, wash twice with anhydrous ethanol, and then place it in a vacuum drying oven at 57℃ for 6.1h to obtain purified bicyclic diacetal tetrahydroxy monomer. Step S3: Add 15g of purified bicyclic diacetal tetrahydroxy monomer, 77g of epichlorohydrin, and 1.5g of tetrabutylammonium bromide to the reactor. Purge with nitrogen for protection and stir at 79℃ and a stirring rate of 350r / min for 3.6h. Afterward, allow to cool naturally to room temperature. Then, while stirring, add 16.5g of sodium hydroxide aqueous solution (40% by mass) dropwise over 75min. After the addition is complete, continue stirring. The reaction was carried out for 4.2 h, followed by filtration. The filtrate was diluted with dichloromethane and washed 5 times with deionized water and 3 times with saturated brine. After each washing, the mixture was allowed to stand for 30 min to separate into layers. The organic phase was collected, dried with anhydrous magnesium sulfate for 43 min, filtered, and the filtrate was transferred to a rotary evaporator and rotary evaporated at 47 °C and -0.095 MPa. The filtrate was then placed in a vacuum drying oven and dried at 57 °C for 5.1 h to obtain glycidyl ether epoxy monomer. Step S4: Add 35g of propylene glycol methyl ether to a four-necked flask, purge with nitrogen for protection, heat to 77°C, and stir at 350 rpm. Mix 64g of methyl methacrylate, 21g of trifluoroethyl methacrylate, 46.5g of butyl acrylate, 14g of acrylic acid, 8g of hydroxyethyl acrylate, and 1.63g of benzoyl peroxide in a constant-pressure dropping funnel, controlling the dropping time to 3.1h. When half of the mixture has been added, add 0.82g of benzoyl peroxide. After the addition is complete, continue the reaction for 2.1h, cool to 70°C, and then add 0.95g of triethylamine. Stir for 6 minutes, then add 46.5 g of glycidyl ether epoxy monomer dropwise over a time of 1.4 hours. Continue the reaction for 4.1 hours. After the reaction is complete, cool down to 50°C, increase the stirring speed to 1500 r / min, and add AMP-95 multifunctional additive to adjust the pH to 5.5. Then, add 82 g of deionized water dropwise at a rate of 1 g / min, then adjust the rate to 2 g / min and continue adding 163 g of deionized water dropwise over a time of 55 minutes. Next, add 0.585 g of silicone defoamer (Tego Foamex 810) and 0.35 g of preservative and mildew inhibitor (BIT-20). Continue stirring for 33 minutes and filter through a 200-mesh nylon filter to obtain waterborne epoxy-acrylic composite resin. Step S5: Add 110g of oily aluminum silver paste (particle size 17μm) and 385mL of isopropanol to a beaker. Stir at 290r / min for 17min, then ultrasonically disperse at 250W for 16min. Filter, wash the filter cake three times with isopropanol, disperse the filter cake in 385mL of isopropanol, transfer to a four-necked flask, purge with nitrogen, and maintain at 43℃ and a stirring rate of 290r / min. Under the condition of n, the pH was adjusted to 8.6 with ammonia water, and then 55 mL of tetraethyl orthosilicate-isopropanol solution (tetraethyl orthosilicate-isopropanol solution is a solution of tetraethyl orthosilicate and isopropanol mixed in a ratio of 15 g: 50 mL) was added dropwise while stirring. The dropwise addition time was controlled at 4.1 h. After the addition was completed, the reaction was kept at the temperature for 6.1 h, then naturally cooled to room temperature and aged for 12.5 h. The mixture was then filtered and the filter cake was washed three times with anhydrous ethanol to obtain a silica-coated aluminum silver paste wet cake. Step S6: Disperse 110g of silica-coated aluminum silver paste wet cake in 330mL of isopropanol, transfer it to a four-necked flask, purge with nitrogen, and under conditions of 47℃ and stirring speed of 290r / min, add 22mL of silane coupling agent solution (the silane coupling agent solution is a mixture of γ-methacryloxypropyltrimethoxysilane and isopropanol in a ratio of 2g:20mL) dropwise while stirring, controlling the dropwise addition time to 65min. After the dropwise addition is complete, continue the reaction for 3.8h, filter, wash the filter cake twice with anhydrous ethanol, disperse the filter cake in 135g of propylene glycol methyl ether, stir for 30min under nitrogen protection, and pass through a 200-mesh sieve to obtain double-coated floating aluminum silver paste; Step S7: Weigh out 20 parts of dispersant, 14.5 parts of passivating agent, 293 parts of deionized water, 173 parts of double-coated floating aluminum silver paste, 12.5 parts of orientation agent, 560 parts of waterborne epoxy-acrylic composite resin, 20 parts of dodecyl alcohol ester, 80 parts of fluorescent whitening agent solution, 16 parts of leveling agent, 0.4 parts of silicone defoamer, and 0.4 parts of preservative and mildew inhibitor according to the following weight proportions, and set aside for later use; Step S8: First, add the dispersant (DISPERBYK-192) and passivator (Tech-8892) to deionized water and stir for 6 minutes at a stirring speed of 490 rpm. Then, add the double-coated floating aluminum silver paste and stir for 16 minutes at a stirring speed of 790 rpm. After that, reduce the stirring speed to 490 rpm and add the orientation agent (Disparlon 6900-20X). Stir for 6 minutes, then add the waterborne epoxy-acrylic composite resin and stir for 11 minutes. Next, add the dodecyl alcohol ester, the fluorescent whitening agent solution (a solution of 2,5-bis(5-tert-butyl-2-benzoxazolyl)thiophene and propylene glycol methyl ether mixed at a ratio of 0.4 g: 100 g), and the leveling agent (TEGO Glide). 410), silicone defoamer (model Tego Foamex 810) and preservative and mildew inhibitor (model BIT-20), increase the stirring speed to 950 r / min, stir for 21 min, decrease the stirring speed to 300 r / min, add triethanolamine dropwise until the pH value is 6.6, stir for 6 min, and then filter through a 200 mesh filter to obtain component A; Step S9: Before use, mix component A and component B (component B is a water-based curing agent, model Bayhydur). Mix BL 5140 and BL 5140 at a mass ratio of 9:1 and stir for 9 minutes at a stirring rate of 350 r / min to obtain water-based silver powder paint.

[0034] Example 3: This embodiment describes a method for producing an environmentally friendly, water-based silver powder paint with an electroplating silver effect, comprising the following steps: Step S1: 0.4 mol protocatechuic aldehyde, 0.2 mol erythritol, 0.0084 mol p-toluenesulfonic acid monohydrate, 60 mL anhydrous N,N-dimethylformamide, and 120 mL petroleum ether were added to a single-necked round-bottom flask equipped with a magnetic stir bar, a water separator, and a reflux condenser. Nitrogen gas was introduced for protection, and the mixture was stirred at 90 °C and a stirring rate of 400 r / min for 24 h. After the reaction was completed, the mixture was allowed to cool naturally to room temperature. The reaction solution was poured into 1000 mL of sodium bicarbonate aqueous solution (sodium bicarbonate aqueous solution mass fraction was 3%) while stirring. A precipitate was formed and collected by suction filtration using a Buchner funnel. The precipitate was washed with deionized water until the pH of the filtrate was neutral. The filter cake was placed in a vacuum drying oven and dried at 60 °C for 6.2 h to obtain the dicyclic diacetal tetrahydroxy monomer. Step S2: Add 20g of bicyclic diacetal tetrahydroxy monomer, 80mL of anhydrous ethanol and 20mL of deionized water to a single-necked round-bottom flask equipped with a spherical condenser. Purge with nitrogen for protection and stir at 400r / min for 17min. Then raise the water bath temperature to 75℃ and stir for 22min. Add 2g of activated carbon (particle size of 60-80μm) and continue stirring for 35min. Filter while hot (temperature >60℃). Allow the filtrate to cool to room temperature and then transfer it to a 4℃ refrigerator for 12h. Collect the precipitate by vacuum filtration, wash twice with anhydrous ethanol, and then place it in a vacuum drying oven and dry at 60℃ for 6.2h to obtain purified bicyclic diacetal tetrahydroxy monomer. Step S3: 20g of purified bicyclic diacetal tetrahydroxy monomer, 102g of epichlorohydrin, and 2g of tetrabutylammonium bromide were added to a reaction vessel. Nitrogen gas was introduced for protection, and the reaction was stirred at 80℃ and 400r / min for 3.8h. After that, the mixture was allowed to cool naturally to room temperature. Then, 22g of sodium hydroxide aqueous solution (40% by mass) was added dropwise while stirring, with the addition time controlled at 80min. After the addition was completed, the reaction was stirred for another 4.5h. The mixture was then filtered, and the filtrate was diluted with dichloromethane. It was washed 5 times with deionized water and 3 times with saturated brine. After each washing, the mixture was allowed to stand for 30min to separate into layers. The organic phase was collected, dried with anhydrous magnesium sulfate for 45min, filtered, and the filtrate was transferred to a rotary evaporator. The mixture was rotary evaporated at 50℃ and -0.095MPa. After that, it was placed in a vacuum drying oven and dried at 60℃ for 5.2h to obtain glycidyl ether epoxy monomer. Step S4: Add 40g of propylene glycol methyl ether to a four-necked flask, purge with nitrogen for protection, heat to 78°C, and stir at 400 rpm. Mix 73g of methyl methacrylate, 24g of trifluoroethyl methacrylate, 53g of butyl acrylate, 16g of acrylic acid, 9g of hydroxyethyl acrylate, and 1.86g of benzoyl peroxide in a constant-pressure dropping funnel. Control the dropping time to 3.2h. When half of the mixture has been added, add 0.94g of benzoyl peroxide. After the addition is complete, continue the reaction for 2.2h, cool to 70°C, and then add 1.1g of triethylamine. Stir for 7 minutes, then add 53g of glycidyl ether epoxy monomer dropwise over a time of 1.5 hours. Continue the reaction for 4.2 hours. After the reaction is complete, cool to 50°C, increase the stirring speed to 1500 r / min, and add AMP-95 multifunctional additive to adjust the pH to 6. Then, add 186g of deionized water dropwise at a rate of 1g / min, then adjust the rate to 2g / min and continue adding the remaining 94g of deionized water over a time of 60 minutes. After that, add 0.67g of silicone defoamer (Tego Foamex 810) and 0.4g of preservative and mildew inhibitor (BIT-20). Continue stirring for 35 minutes and filter through a 200-mesh nylon filter to obtain waterborne epoxy-acrylic composite resin. Step S5: Add 120g of oily aluminum silver paste (particle size 20μm) and 420mL of isopropanol to a beaker. Stir at 300r / min for 20min, then ultrasonically disperse at 300W for 17min. Filter, wash the filter cake three times with isopropanol, disperse the filter cake in 420mL of isopropanol, transfer to a four-necked flask, purge with nitrogen, and maintain at 45℃ and a stirring speed of 300r / min. Under the conditions of in, the pH was adjusted to 8.7 with ammonia water, and then 60 mL of tetraethyl orthosilicate-isopropanol solution (tetraethyl orthosilicate-isopropanol solution is a solution of tetraethyl orthosilicate and isopropanol mixed in a ratio of 15 g: 50 mL) was added dropwise while stirring. The dropwise addition time was controlled at 4.2 h. After the addition was completed, the reaction was kept at the temperature for 6.2 h, then naturally cooled to room temperature and aged for 13 h. The mixture was then filtered and the filter cake was washed three times with anhydrous ethanol to obtain a silica-coated aluminum silver paste wet cake. Step S6: Disperse 120g of silica-coated aluminum silver paste wet cake in 360mL of isopropanol, transfer it to a four-necked flask, purge with nitrogen, and under conditions of 50℃ and a stirring rate of 300r / min, add 24mL of silane coupling agent solution (the silane coupling agent solution is a mixture of γ-methacryloxypropyltrimethoxysilane and isopropanol in a ratio of 2g:20mL) dropwise while stirring. Control the dropping time to 70min. After the dropping is completed, continue the reaction for 4h, filter, wash the filter cake twice with anhydrous ethanol, disperse the filter cake in 160g of propylene glycol methyl ether, stir for 30min under nitrogen protection, and pass through a 200-mesh sieve to obtain double-coated floating aluminum silver paste. Step S7: Weigh out 25 parts of dispersant, 18 parts of passivating agent, 366 parts of deionized water, 216 parts of double-coated floating aluminum silver paste, 15 parts of orientation agent, 700 parts of waterborne epoxy-acrylic composite resin, 25 parts of dodecyl alcohol ester, 100 parts of fluorescent whitening agent solution, 20 parts of leveling agent, 0.5 parts of silicone defoamer, and 0.5 parts of preservative and mildew inhibitor according to the following weight proportions, and set aside. Step S8: First, add the dispersant (DISPERBYK-192) and passivator (Tech-8892) to deionized water and stir for 7 minutes at a stirring speed of 500 rpm. Then, add the double-coated floating aluminum silver paste and stir for 17 minutes at a stirring speed of 800 rpm. After that, reduce the stirring speed to 500 rpm and add the orientation agent (Disparlon 6900-20X). Stir for 7 minutes, then add the waterborne epoxy-acrylic composite resin and stir for 12 minutes. Next, add the dodecyl alcohol ester, the fluorescent whitening agent solution (a solution of 2,5-bis(5-tert-butyl-2-benzoxazolyl)thiophene and propylene glycol methyl ether mixed at a ratio of 0.4 g: 100 g), and the leveling agent (TEGO Glide). 410), silicone defoamer (model Tego Foamex 810) and preservative and mildew inhibitor (model BIT-20), increase the stirring speed to 1000 r / min, stir for 22 min, decrease the stirring speed to 300 r / min, add triethanolamine dropwise until the pH value is 6.8, stir for 7 min, and then filter through a 200 mesh filter to obtain component A; Step S9: Before use, mix component A and component B (component B is a water-based curing agent, model Bayhydur). Mix BL 5140 and BL 5140 at a mass ratio of 9:1 and stir for 10 minutes at a stirring speed of 400 r / min to obtain water-based silver powder paint.

[0035] Comparative Example 1: This comparative example demonstrates a method for preparing an environmentally friendly, water-based silver powder paint with an electroplating silver effect, including the following steps: Step S1: Add 30g of propylene glycol methyl ether to a four-necked flask, purge with nitrogen for protection, heat to 75°C, and stir at 300 rpm. Mix 55g of methyl methacrylate, 18g of trifluoroethyl methacrylate, 40g of butyl acrylate, 12g of acrylic acid, 7g of hydroxyethyl acrylate, and 1.4g of benzoyl peroxide in a constant pressure dropping funnel, and control the dropping time for 3 hours. When half of the mixture has been added, add 0.7g of benzoyl peroxide. After the addition is complete, continue the reaction for 2 hours, cool to 50°C, increase the stirring speed to 1500 rpm, and add AMP-95 multifunctional additive to adjust the pH to 5. Then, add 140g of deionized water at a rate of 1g / min, then adjust the dropping rate to 2g / min and continue adding 70g of deionized water, controlling the dropping time for 50 minutes. Finally, add 0.50g of silicone defoamer (the silicone defoamer is Tego Foamex). Add 810) and 0.3g of preservative and mildew inhibitor (model BIT-20), stir for 30 minutes, filter with a 200-mesh nylon filter to obtain water-based acrylic resin; Step S2: Add 100g of oily aluminum silver paste (particle size of 15μm) and 350mL of isopropanol to a beaker. Stir for 15min at a stirring rate of 280r / min, then ultrasonically disperse for 17min at an ultrasonic power of 200W. Filter, wash the filter cake three times with isopropanol, disperse the filter cake in 350mL of isopropanol, transfer to a four-necked flask, purge with nitrogen for protection, and maintain at 40℃ and a stirring rate of 280r. Under the condition of / min, the pH was adjusted to 8.5 with ammonia water, and then 50 mL of tetraethyl orthosilicate-isopropanol solution (tetraethyl orthosilicate-isopropanol solution is a solution of tetraethyl orthosilicate and isopropanol mixed in a ratio of 15 g: 50 mL) was added dropwise while stirring. The dropwise addition time was controlled at 4 h. After the addition was completed, the reaction was kept at the temperature for 6 h, then naturally cooled to room temperature and aged for 12 h. The mixture was then filtered and the filter cake was washed 3 times with anhydrous ethanol to obtain a silica-coated aluminum silver paste wet cake. Step S3: Disperse 100g of silica-coated aluminum silver paste wet cake in 300mL of isopropanol, transfer it to a four-necked flask, purge with nitrogen, and under conditions of 45℃ and stirring speed of 280r / min, add 20mL of silane coupling agent solution (the silane coupling agent solution is a mixture of γ-methacryloxypropyltrimethoxysilane and isopropanol in a ratio of 2g:20mL) dropwise while stirring, controlling the dropwise addition time to 60min. After the dropwise addition is complete, continue the reaction for 3.5h, filter, wash the filter cake twice with anhydrous ethanol, disperse the filter cake in 110g of propylene glycol methyl ether, stir for 30min under nitrogen protection, and pass through a 200-mesh sieve to obtain double-coated floating aluminum silver paste; Step S4: Weigh out 15 parts of dispersant, 11 parts of passivating agent, 220 parts of deionized water, 130 parts of double-coated floating aluminum silver paste, 10 parts of orientation agent, 420 parts of water-based acrylic resin, 15 parts of dodecyl alcohol ester, 60 parts of fluorescent whitening agent solution, 12 parts of leveling agent, 0.3 parts of silicone defoamer, and 0.3 parts of preservative and mildew inhibitor according to the following weight proportions, and set aside for later use; Step S5: First, add the dispersant (DISPERBYK-192) and passivator (Tech-8892) to deionized water and stir for 5 minutes at a stirring speed of 480 rpm. Then, add the double-coated floating aluminum silver paste and stir for 15 minutes at a stirring speed of 780 rpm. After that, reduce the stirring speed to 480 rpm and add the orientation agent (Disparlon 6900-20X). Stir for 5 minutes, then add the water-based acrylic resin and stir for 10 minutes. Next, add the dodecyl alcohol ester, fluorescent whitening agent solution (a solution of 2,5-bis(5-tert-butyl-2-benzoxazolyl)thiophene and propylene glycol methyl ether mixed at a ratio of 0.4 g: 100 g), leveling agent (TEGO Glide 410), and silicone defoamer (Tego). Foamex 810) and a preservative and mildew inhibitor (model BIT-20) were added. The stirring speed was increased to 900 r / min and stirred for 20 min. The stirring speed was then reduced to 300 r / min. Triethanolamine was added dropwise until the pH value was 6.5 and stirred for 5 min. The mixture was then filtered through a 200-mesh filter to obtain component A. Step S6: Before use, mix component A and component B (component B is a water-based curing agent, model Bayhydur). Mix BL 5140 and BL 5140 at a mass ratio of 9:1 and stir for 8 minutes at a stirring speed of 300 r / min to obtain water-based silver powder paint.

[0036] Comparative Example 2: This comparative example demonstrates a method for preparing an environmentally friendly, water-based silver powder paint with an electroplating silver effect, including the following steps: Step S1: 0.2 mol protocatechuic aldehyde, 0.1 mol erythritol, 0.0042 mol p-toluenesulfonic acid monohydrate, 30 mL anhydrous N,N-dimethylformamide, and 60 mL petroleum ether were added to a single-necked round-bottom flask equipped with a magnetic stir bar, a water separator, and a reflux condenser. Nitrogen gas was introduced for protection, and the mixture was stirred at 85 °C and a stirring rate of 300 r / min for 24 h. After the reaction was completed, the mixture was allowed to cool naturally to room temperature. The reaction solution was poured into 500 mL of sodium bicarbonate aqueous solution (sodium bicarbonate aqueous solution mass fraction was 3%) while stirring. A precipitate was formed and collected by suction filtration using a Buchner funnel. The precipitate was washed with deionized water until the pH of the filtrate was neutral. The filter cake was placed in a vacuum drying oven and dried at 55 °C for 6 h to obtain the dicyclic diacetal tetrahydroxy monomer. Step S2: Add 10g of bicyclic diacetal tetrahydroxy monomer, 40mL of anhydrous ethanol and 10mL of deionized water to a single-necked round-bottom flask equipped with a spherical condenser. Purge with nitrogen for protection and stir at 300r / min for 15min. Then raise the water bath temperature to 75℃ and stir for 20min. Add 1g of activated carbon (60μm particle size) and continue stirring for 30min. Filter while hot (temperature > 60℃). Allow the filtrate to cool to room temperature and then transfer it to a 4℃ refrigerator for 12h. Collect the precipitate by vacuum filtration, wash twice with anhydrous ethanol, and then place it in a vacuum drying oven at 55℃ for 6h to obtain purified bicyclic diacetal tetrahydroxy monomer. Step S3: 10g of purified bicyclic diacetal tetrahydroxy monomer, 51g of epichlorohydrin and 1g of tetrabutylammonium bromide were added to the reaction vessel, and nitrogen gas was introduced for protection. The reaction was stirred at 78℃ and 300r / min for 3.5h. After that, it was naturally cooled to room temperature. Then, 11g of sodium hydroxide aqueous solution (40% by mass) was added dropwise while stirring, and the addition time was controlled at 70min. After the addition was completed, the reaction was stirred for another 4h. After that, the mixture was filtered, and the filtrate was diluted with dichloromethane. It was washed 5 times with deionized water and 3 times with saturated brine. After each washing, the mixture was allowed to stand for 30min to separate into layers. The organic phase was collected, dried with anhydrous magnesium sulfate for 40min, filtered, and the filtrate was transferred to a rotary evaporator. It was rotary evaporated at 45℃ and -0.095MPa. After that, it was placed in a vacuum drying oven and dried at 55℃ for 5h to obtain glycidyl ether epoxy monomer. Step S4: Add 30g of propylene glycol methyl ether to a four-necked flask, purge with nitrogen for protection, heat to 75°C, and stir at 300 rpm. Mix 55g of methyl methacrylate, 18g of trifluoroethyl methacrylate, 40g of butyl acrylate, 12g of acrylic acid, 7g of hydroxyethyl acrylate, and 1.4g of benzoyl peroxide in a constant-pressure dropping funnel, controlling the dropping time to 3 hours. When half of the mixture has been added, add 0.7g of benzoyl peroxide. After the addition is complete, continue the reaction for 2 hours, cool to 70°C, and then add 0.8g of triethylamine. Stir for 5 hours. Add 40g of glycidyl ether epoxy monomer dropwise over a time of 1.3 hours, and continue the reaction for 4 hours. After the reaction is complete, cool the mixture to 50°C, increase the stirring speed to 1500 r / min, and add AMP-95 multifunctional additive to adjust the pH to 5. Then, add 140g of deionized water dropwise at a rate of 1g / min, then adjust the dropping rate to 2g / min and continue adding 70g of deionized water dropwise over a time of 50 minutes. After that, add 0.50g of silicone defoamer (TegoFoamex 810) and 0.3g of preservative and mildew inhibitor (BIT-20), and continue stirring for 30 minutes. Filter the mixture through a 200-mesh nylon filter to obtain the waterborne epoxy-acrylic composite resin. Step S5: Weigh out 15 parts of dispersant, 11 parts of passivating agent, 220 parts of deionized water, 130 parts of oil-based aluminum silver paste, 10 parts of orientation agent, 420 parts of water-based epoxy-acrylic composite resin, 15 parts of dodecyl alcohol ester, 60 parts of fluorescent whitening agent solution, 12 parts of leveling agent, 0.3 parts of silicone defoamer, and 0.3 parts of preservative and mildew inhibitor according to the following weight proportions, and set aside for later use; Step S6: First, add the dispersant (DISPERBYK-192) and passivator (Tech-8892) to deionized water and stir for 5 minutes at a stirring speed of 480 rpm. Then, add the oil-based aluminum silver paste (15 μm particle size) and stir for 15 minutes at a stirring speed of 780 rpm. After that, reduce the stirring speed to 480 rpm and add the orientation agent (Disparlon 6900-20X). Stir for 5 minutes, then add the water-based epoxy-acrylic composite resin and stir for 10 minutes. Next, add the dodecyl alcohol ester, the fluorescent whitening agent solution (a solution of 2,5-bis(5-tert-butyl-2-benzoxazolyl)thiophene and propylene glycol methyl ether mixed at a ratio of 0.4 g: 100 g), and the leveling agent (TEGO Glide). 410), silicone defoamer (model Tego Foamex 810) and preservative and mildew inhibitor (model BIT-20), increase the stirring speed to 900 r / min, stir for 20 min, reduce the stirring speed to 300 r / min, add triethanolamine dropwise until the pH value is 6.5, stir for 5 min, and then filter through a 200 mesh filter to obtain component A; Step S7: Before use, mix component A and component B (component B is a water-based curing agent, model Bayhydur). Mix BL 5140 and BL 5140 at a mass ratio of 9:1 and stir for 8 minutes at a stirring speed of 300 r / min to obtain water-based silver powder paint.

[0037] Comparative Example 3: This comparative example demonstrates a method for preparing an environmentally friendly, water-based silver powder paint with an electroplating silver effect, including the following steps: Step S1: Add 30g of propylene glycol methyl ether to a four-necked flask, purge with nitrogen for protection, heat to 75°C, and stir at 300 rpm. Mix 55g of methyl methacrylate, 18g of trifluoroethyl methacrylate, 40g of butyl acrylate, 12g of acrylic acid, 7g of hydroxyethyl acrylate, and 1.4g of benzoyl peroxide in a constant pressure dropping funnel, and control the dropping time for 3 hours. When half of the mixture has been added, add 0.7g of benzoyl peroxide. After the addition is complete, continue the reaction for 2 hours, cool to 50°C, increase the stirring speed to 1500 rpm, and add AMP-95 multifunctional additive to adjust the pH to 5. Then, add 140g of deionized water at a rate of 1g / min, then adjust the dropping rate to 2g / min and continue adding 70g of deionized water, controlling the dropping time for 50 minutes. Finally, add 0.50g of silicone defoamer (the silicone defoamer is Tego Foamex). Add 810) and 0.3g of preservative and mildew inhibitor (model BIT-20), stir for 30 minutes, filter with a 200-mesh nylon filter to obtain water-based acrylic resin; Step S2: Weigh out 15 parts of dispersant, 11 parts of passivating agent, 220 parts of deionized water, 130 parts of oil-based aluminum silver paste, 10 parts of orientation agent, 420 parts of water-based acrylic resin, 15 parts of dodecyl alcohol ester, 60 parts of fluorescent whitening agent solution, 12 parts of leveling agent, 0.3 parts of silicone defoamer, and 0.3 parts of preservative and mildew inhibitor according to the following weight proportions, and set aside for later use; Step S3: First, add the dispersant (DISPERBYK-192) and passivator (Tech-8892) to deionized water and stir for 5 minutes at a stirring speed of 480 rpm. Then, add the oil-based aluminum silver paste (15 μm particle size) and stir for 15 minutes at a stirring speed of 780 rpm. After that, reduce the stirring speed to 480 rpm and add the orientation agent (Disparlon 6900-20X). Stir for 5 minutes, then add the water-based acrylic resin and stir for 10 minutes. Next, add the dodecyl alcohol ester, the fluorescent whitening agent solution (a solution of 2,5-bis(5-tert-butyl-2-benzoxazolyl)thiophene and propylene glycol methyl ether mixed at a ratio of 0.4 g: 100 g), and the leveling agent (TEGO Glide). 410), silicone defoamer (model Tego Foamex 810) and preservative and mildew inhibitor (model BIT-20), increase the stirring speed to 900 r / min, stir for 20 min, reduce the stirring speed to 300 r / min, add triethanolamine dropwise until the pH value is 6.5, stir for 5 min, and then filter through a 200 mesh filter to obtain component A; Step S4: Before use, mix component A and component B (component B is a water-based curing agent, model Bayhydur). Mix BL 5140 and BL 5140 at a mass ratio of 9:1 and stir for 8 minutes at a stirring speed of 300 r / min to obtain water-based silver powder paint.

[0038] Performance testing The water-based silver powder paints of Examples 1-3 and Comparative Examples 1-3 were tested according to the following methods; 60° Mirror Gloss Test: Water-based silver powder paint was sprayed onto a flat tinplate, with the dry film thickness controlled at 20μm. It was cured for 7 days at a temperature of 23℃ and a relative humidity of 50%. The gloss meter was calibrated using a standard plate. Five different locations were selected on the sample surface for testing. Each location was tested once. The maximum and minimum values ​​were discarded, and the arithmetic mean of the remaining three test values ​​was taken as the final result, accurate to 1°.

[0039] Aluminum sheet parallel alignment rate test: The cured paint film sample was brittlely fractured with liquid nitrogen, the cross-section was cut off, and gold was sprayed on using an ion sputtering instrument. The cross-sectional morphology of the paint film was observed under SEM with a magnification of 500-1000x. Ten different fields of view were randomly selected, and the orientation of at least 50 aluminum sheets in each field of view was counted. The angle between the aluminum sheet and the paint film surface was defined as ≤15° as parallel alignment. The percentage of parallel alignment aluminum sheets to the total number of aluminum sheets counted was calculated to the nearest 1%.

[0040] Pencil hardness test: The sample preparation method is the same as that for the 60° mirror gloss test. The pencil is sharpened to expose 5mm of lead, and the end face is smoothed on sandpaper. The pencil is fixed at a 45° angle on the hardness tester, a load of 1000g is applied, and the hardness tester is pushed to pass through the paint film surface at a uniform speed for about 10mm. Five positions are tested for each hardness level. The hardness level of the hardest pencil that does not cause scratches to the paint film is taken as the pencil hardness of the paint film.

[0041] Stability test: The water-based silver powder paint of component A was put into a glass bottle with a stopper, the sample volume was 4 / 5 of the bottle volume, and sealed. The sealed sample was placed in a constant temperature oven at 50℃ and left for 30 consecutive days. After that, it was taken out and left at room temperature for 24 hours. The results were observed and recorded to see if the sample showed any phenomena such as layering, precipitation, gas expansion, or discoloration.

[0042] Salt spray resistance test: Water-based silver powder paint was sprayed onto a 150mm×70mm×0.8mm cold-rolled steel plate (model Q235), with a dry film thickness controlled at 20μm. The plate was cured for 7 days under standard conditions. The edges and bottom were sealed with a mixture of paraffin and rosin. A 5% sodium chloride aqueous solution was prepared, and the pH was adjusted to 7. The sample was placed at a 30° angle to the vertical direction in a salt spray test chamber at 35℃. The sedimentation rate was 1mL / (80cm). 2• h), spray continuously, observe the surface phenomena of the sample periodically, and record the time when defects appear.

[0043] The test results are shown in Table 1: Table 1: Test Results Summary Table

[0044] Referring to the table above, based on the comparison between Examples 1-3 and Comparative Examples 1-3, it can be seen that water-based silver powder paint has high mirror gloss, excellent storage stability, high hardness and excellent salt spray resistance, and is environmentally friendly with low VOC, fully meeting the requirements of high-end industrial coating.

[0045] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0046] The above description is merely an example and illustration of the present invention. Those skilled in the art can make various modifications or additions to the specific embodiments described or use similar methods to replace them, as long as they do not deviate from the invention or exceed the scope defined in this application, they should all fall within the protection scope of the present invention.

Claims

1. A method for producing an environmentally friendly, water-based silver powder paint with an electroplating silver effect, characterized in that, Includes the following steps: Step 1: Weigh out the following components by weight: 15-25 parts dispersant, 11-18 parts passivating agent, 220-366 parts deionized water, 130-216 parts double-coated floating aluminum silver paste, 10-15 parts orientation agent, 420-700 parts waterborne epoxy-acrylic composite resin, 15-25 parts dodecyl alcohol ester, 60-100 parts fluorescent whitening agent solution, 12-20 parts leveling agent, 0.3-0.5 parts silicone defoamer, and 0.3-0.5 parts preservative and mildew inhibitor. Set aside for later use. Step 2: First, add the dispersant and passivator to deionized water and stir. Then, add the double-coated floating aluminum silver paste and stir. Next, add the orientation agent and stir. Then, add the water-based epoxy-acrylic composite resin and stir. Then, add the dodecyl alcohol ester, fluorescent whitening agent solution, leveling agent, silicone defoamer and preservative and mildew inhibitor in sequence and stir. Add triethanolamine dropwise to adjust the pH value and stir. Then filter to obtain component A. Step 3: Before use, mix components A and B at a mass ratio of 9:1 and stir to obtain water-based silver powder paint.

2. The method for producing an environmentally friendly water-based silver powder paint with an electroplating silver effect according to claim 1, characterized in that, The fluorescent whitening agent solution in step two is a solution of 2,5-bis(5-tert-butyl-2-benzoxazolyl)thiophene and propylene glycol methyl ether mixed in a ratio of 0.4g:100g.

3. The method for producing an environmentally friendly, water-based silver powder paint with an electroplating silver effect according to claim 1, characterized in that, Component B in step three is a water-based curing agent.

4. The method for producing an environmentally friendly water-based silver powder paint with an electroplating silver effect according to claim 1, characterized in that, The waterborne epoxy-acrylic composite resin is prepared by the following steps: Step a1: Protocatechuic aldehyde, erythritol, p-toluenesulfonic acid monohydrate, anhydrous N,N-dimethylformamide and petroleum ether were added to a single-necked round-bottom flask, stirred and reacted, cooled, and the reaction solution was poured into an aqueous sodium bicarbonate solution. Then the solution was filtered, washed and dried to obtain the bicyclic diacetal tetrahydroxy monomer. Step a2: Add bicyclic diacetal tetrahydroxy monomer, anhydrous ethanol and deionized water to a single-necked round-bottom flask and stir. Then add activated carbon and continue stirring. Filter while hot, cool, then refrigerate and stand, filter, wash and dry to obtain purified bicyclic diacetal tetrahydroxy monomer. Step a3: The purified bicyclic diacetal tetrahydroxy monomer, epichlorohydrin and tetrabutylammonium bromide were added to the reaction vessel and stirred. After cooling, sodium hydroxide aqueous solution was added and the reaction was continued by stirring. The mixture was filtered, the filtrate was diluted with dichloromethane, washed, the organic phase was collected, dried, filtered, rotary evaporated, and then dried to obtain glycidyl ether epoxy monomer. Step a4: Add propylene glycol methyl ether to a four-necked flask. Mix methyl methacrylate, trifluoroethyl methacrylate, butyl acrylate, acrylic acid, hydroxyethyl acrylate, and 2 / 3 of benzoyl peroxide. Place the mixture in a constant pressure dropping funnel. When half of the mixture has been added, add the remaining 1 / 3 of benzoyl peroxide and continue the reaction. Then add triethylamine and stir. Add glycidyl ether epoxy monomer and continue the reaction. Add AMP-95 multifunctional additive to adjust the pH value. Then add deionized water. Finally, add silicone defoamer and preservative and mildew inhibitor, continue stirring, and filter to obtain waterborne epoxy-acrylic composite resin.

5. The method for producing an environmentally friendly water-based silver powder paint with an electroplating silver effect according to claim 4, characterized in that, In step a1, the ratio of protocatechuic aldehyde, erythritol, p-toluenesulfonic acid monohydrate, anhydrous N,N-dimethylformamide, petroleum ether, and sodium bicarbonate aqueous solution is 0.2-0.4 mol : 0.1-0.2 mol : 0.0042-0.0084 mol : 30-60 mL : 60-120 mL : 500-1000 mL; the mass fraction of the sodium bicarbonate aqueous solution is 3%.

6. The method for producing an environmentally friendly water-based silver powder paint with an electroplating silver effect according to claim 4, characterized in that, In step a2, the ratio of the bicyclic diacetal tetrahydroxy monomer, anhydrous ethanol, deionized water, and activated carbon is 10-20g: 40-80mL: 10-20mL: 1-2g; the particle size of the activated carbon is 60-80μm.

7. The method for producing an environmentally friendly, water-based silver powder paint with an electroplating silver effect according to claim 4, characterized in that, In step a3, the ratio of purified bicyclic diacetal tetrahydroxy monomer, epichlorohydrin, tetrabutylammonium bromide, and sodium hydroxide aqueous solution is 10-20g: 51-102g: 1-2g: 11-22g; the mass fraction of the sodium hydroxide aqueous solution is 40%.

8. The method for producing an environmentally friendly water-based silver powder paint with an electroplating silver effect according to claim 4, characterized in that, The ratio of the following components in step a4 is as follows: propylene glycol methyl ether, methyl methacrylate, trifluoroethyl methacrylate, butyl acrylate, acrylic acid, hydroxyethyl acrylate, benzoyl peroxide, triethylamine, glycidyl ether epoxy monomer, deionized water, silicone defoamer, and preservative and mildew inhibitor.

9. The method for producing an environmentally friendly water-based silver powder paint with an electroplating silver effect according to claim 1, characterized in that, The double-coated floating aluminum silver paste is prepared by the following steps: Step b1: Add oily aluminum silver paste and 1 / 2 isopropanol to a beaker, stir, then ultrasonically disperse, filter, wash, disperse the filter cake in 1 / 2 isopropanol, adjust the pH, then add tetraethyl orthosilicate-isopropanol solution, continue the reaction at a constant temperature, then cool, age, filter, wash, to obtain silica-coated aluminum silver paste wet cake; Step b2: Disperse the silica-coated aluminum silver paste wet cake in isopropanol, add silane coupling agent solution, continue the reaction, filter, wash, disperse the filter cake in propylene glycol methyl ether, stir, and sieve to obtain double-coated floating aluminum silver paste.

10. The method for producing an environmentally friendly water-based silver powder paint with an electroplating silver effect according to claim 9, characterized in that, In step b1, the ratio of the oily aluminum silver paste, isopropanol, and tetraethyl orthosilicate-isopropanol solution is 100-120g: 700-840mL: 50-60mL; the tetraethyl orthosilicate-isopropanol solution in step b1 is a solution prepared by mixing tetraethyl orthosilicate and isopropanol in a ratio of 15g: 50mL; the particle size of the oily aluminum silver paste in step b1 is 15-20μm; in step b2, the ratio of the silica-coated aluminum silver paste wet cake, isopropanol, silane coupling agent solution, and propylene glycol methyl ether is 100-120g: 300-360mL: 20-24mL: 110-160g; the silane coupling agent solution in step b2 is a mixture prepared by mixing γ-methacryloyloxypropyltrimethoxysilane and isopropanol in a ratio of 2g: 20mL.

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