Antiviral coating capable of continuously releasing negative ions and preparation method thereof

Abstract

The invention relates to the technical field of antiviral coatings, and discloses an antiviral coating capable of continuously releasing negative ions and a preparation method thereof, and the method comprises the following steps: raw material preparation, premixing treatment, functional material addition, assistant blending and post-treatment. The bio-based resin is compounded with the negative ion release material, the nano antiviral material and the aldehyde removal catalyst under specific process conditions, a continuous phase formed by the bio-based resin provides a stable carrier for the functional material, so that the functional material can be uniformly dispersed and firmly combined, and the negative ion release material is protected by a resin system, so that the functional material is more stable and reliable. And the nano antiviral material and the formaldehyde removal catalyst have a synergistic effect on the surface and the interior of the coating to jointly construct a long-acting antiviral and formaldehyde purification functional layer, so that the durability and the stability of the multifunctionality of the coating are realized.

Description

Technical Field

[0001] This invention relates to the field of antiviral coating technology, specifically to an antiviral coating capable of continuously releasing negative ions and its preparation method. Background Technology

[0002] In recent years, various pathogenic viruses have posed a serious challenge to public health due to their easy transmissibility. Viral infection is a major cause of human disease, and one of the common ways viruses are transmitted is through indirect contact with elevator buttons, door handles, walls, etc. With social development, people's health and environmental awareness are constantly increasing. For the surface coating field, coatings that only provide aesthetics and protection are increasingly unable to meet the requirements. People also need coatings that have health benefits.

[0003] Currently, due to various limitations in functionality and preparation processes, traditional coatings cannot achieve a continuous and stable release of negative ions when used for indoor environmental coatings. Uneven dispersion of negative ion-releasing materials in the coating or their susceptibility to deactivation due to environmental factors can lead to large fluctuations in negative ion concentration, affecting the long-term and uniformity of air purification effects. Furthermore, traditional coatings often rely on single active ingredients in their antiviral design, failing to achieve synergistic effects of antiviral and formaldehyde removal. Their removal efficiency for specific viruses and harmful gases is insufficient, making it difficult to cope with multiple pollutants in complex environments. In addition, imperfect mixing processes and rough post-treatment during coating preparation can easily lead to nanomaterial agglomeration, uneven catalyst distribution, and poor stability, resulting in short coating shelf life, poor leveling during application, and rapid degradation of coating performance, thus affecting the actual application effect and durability of the coating.

[0004] Therefore, an antiviral coating capable of continuously releasing negative ions and its preparation method are proposed to solve the above problems. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides an antiviral coating capable of continuously releasing negative ions and its preparation method. The antiviral coating provided by this invention, capable of continuously releasing negative ions, solves the problems mentioned in the background technology, such as large fluctuations in negative ion release concentration, affecting the long-term and uniform air purification effect, difficulty in dealing with multiple pollutants in complex environments, and affecting the actual application effect and durability of the coating.

[0006] To achieve the above objectives, the present invention provides the following technical solution: an antiviral coating capable of continuously releasing negative ions and a method for preparing the same, the method comprising the following steps:

[0007] Step 1: Raw material preparation, selecting bio-based resin, negative ion releasing material, nano antiviral material, formaldehyde removal catalyst, water and additives as basic raw materials;

[0008] Step 2: Premixing treatment. Add bio-based resin and water to a mixing device and stir at 200-500 r / min for 10-20 minutes at room temperature to form a uniform emulsion.

[0009] Step 3: Add functional materials. Add negative ion releasing material, nano antiviral material and formaldehyde removal catalyst to the emulsion obtained in Step 2 in sequence. Control the temperature at 25-35℃ and stir at 300-600r / min for 20-40 minutes to make the materials evenly dispersed.

[0010] Step 4: Additive blending. Add dispersant, defoamer, thickener and preservative to the mixture obtained in Step 3. Increase the stirring speed to 500-1000 r / min and continue stirring for 15-30 minutes to adjust the viscosity and stability of the coating.

[0011] Step 5: Post-processing. The coating obtained in Step 4 is ground to a fineness of ≤50μm using a grinding equipment, then filtered and packaged to obtain the final antiviral coating.

[0012] Preferably, in step one, the bio-based resin is at least one of bio-based acrylic resin, epoxy soybean oil resin, or polylactic acid resin, with a solid content of 40%-60% and a pH value of 7.5-9.0; the negative ion releasing material is at least one of tourmaline powder, negative ion ceramic powder, or diatomaceous earth, with a particle size range of 1-10 μm; and the nano antiviral material is at least one of nano silver, nano zinc oxide, or nano titanium dioxide, with a particle size range of 10-100 nm.

[0013] Preferably, the aldehyde removal catalyst is activated by the following method: placing the catalyst in a muffle furnace and calcining it at 300-500°C for 2-4 hours, then immersing it in a 0.1-0.5 mol / L silver nitrate solution or platinum chloride solution for 10-30 minutes, and then drying it.

[0014] Preferably, the bio-based resin is prepared by the following method: selecting one of corn starch, soybean oil or plant cellulose as raw material, adding the raw material and deionized water to a reaction vessel, with the mass ratio of raw material to water being 1:2-1:4, controlling the temperature at 60-80℃, stirring at 100-300 r / min for 30-60 minutes, then adding 0.1-0.5 parts by weight of ammonium persulfate catalyst, raising the temperature to 80-100℃ and reacting for 2-4 hours, and adjusting the pH to neutral after cooling to obtain a bio-based resin emulsion.

[0015] Preferably, in step two, the premixing treatment includes the following sub-steps: first, heating the water to 30-40℃, then slowly adding the bio-based resin while stirring at a speed of 200-500 r / min, and using ultrasonic-assisted dispersion during the stirring process; the ultrasonic-assisted dispersion is achieved by an immersion ultrasonic probe, the frequency of the ultrasonic wave is 20-40kHz, the power density is 50-150W / L, the treatment method is intermittent, that is, working for 5-10 seconds and then pausing for 2-5 seconds, the treatment time is 5-15 minutes, and the resin is completely emulsified.

[0016] Preferably, in step three, the order of adding functional materials is as follows: first add the negative ion releasing material, stir for 10-15 minutes, then add the nano antiviral material, continue stirring for 10-15 minutes, and finally add the formaldehyde removal catalyst; the stirring equipment is a reaction vessel with a temperature control and vacuum system, the vacuum degree is controlled at -0.05 to -0.1 MPa, and bubbles are removed.

[0017] Preferably, the nano-antiviral material is prepared by the following method: selecting one of silver nitrate, zinc sulfate or tetrabutyl titanate as a precursor, dissolving it in deionized water at a concentration of 0.1-0.5 mol / L, adding 0.1-0.3 parts by weight of sodium citrate as a stabilizer, stirring at 500-1000 r / min for 1-2 hours at 60-80℃, and then synthesizing nanoparticles by precipitation or sol-gel method;

[0018] When synthesizing by precipitation method, slowly add a precipitant sodium hydroxide or sodium carbonate solution with a concentration of 0.5-1.5 mol / L to the above precursor solution, controlling the adding rate to 1-3 mL / min, until the pH value of the solution reaches 8-11, and continue stirring and maturing for 1-3 hours;

[0019] When synthesizing using the sol-gel method, nitric acid or ammonia, accounting for 5%-15% of the molar amount of the precursor, is added to the above precursor solution and aged at 40-60℃ for 12-48 hours to form a sol. Then, the temperature is raised to 60-80℃ and the aging continues for 24-72 hours to transform it into a gel.

[0020] The products obtained by the precipitation method or sol-gel method are centrifuged, washed and dried to obtain nanomaterials with a particle size of 10-100 nm. The centrifugation speed is 8000-12000 rpm and the time is 10-20 minutes. The washing is performed by alternating between deionized water and anhydrous ethanol 2-3 times each. The drying is carried out in a vacuum drying oven at a temperature of 60-80℃ for 2-4 hours.

[0021] Preferably, in step four, the additives include a dispersant, a defoamer, a thickener, and a preservative, wherein the dispersant is at least one of polyvinylpyrrolidone or sodium polyacrylate, and the amount added is 0.5-1.5 parts by weight; the defoamer is at least one of silicone defoamer or mineral oil defoamer, and the amount added is 0.1-0.5 parts by weight; the thickener is at least one of hydroxyethyl cellulose or polyurethane thickener, and the amount added is 0.3-1.0 parts by weight; and the preservative is at least one of isothiazolinone or benzisothiazolinone, and the amount added is 0.1-0.3 parts by weight.

[0022] Preferably, in step five, the grinding equipment is a sand mill or a ball mill, the grinding media is zirconia beads with a diameter of 0.5-1.0 mm, and the grinding time is 30-60 minutes; the filtration uses a 200-400 mesh sieve, the filtration pressure is 0.1-0.3 MPa, and the viscosity of the coating is 80-120 KU with a fineness ≤50 μm.

[0023] Preferably, the coating is composed of the following raw materials in parts by weight: 30-50 parts of bio-based resin, 5-15 parts of negative ion releasing material, 1-5 parts of nano antiviral material, 5-10 parts of formaldehyde removal catalyst, 20-40 parts of water, and 1-5 parts of additives; the formaldehyde removal catalyst is at least one of photocatalyst titanium dioxide, manganese-based catalyst, or molecular sieve catalyst, with a specific surface area ≥100m² / g.

[0024] Compared with existing technologies, this invention provides an antiviral coating capable of continuously releasing negative ions and its preparation method, which has the following beneficial effects:

[0025] 1. In this invention, bio-based resin is compounded with negative ion releasing materials, nano-antiviral materials, and formaldehyde removal catalysts under specific process conditions. The continuous phase formed by the bio-based resin provides a stable carrier for the functional materials, enabling them to be uniformly dispersed and firmly bonded. The negative ion releasing materials, with the protection of the resin system, can continuously and stably release negative ions into the environment. The nano-antiviral materials and formaldehyde removal catalysts work synergistically on the surface and inside of the coating to jointly construct a long-lasting antiviral and formaldehyde-purifying functional layer, thereby achieving the durability and stability of the coating's multifunctionality.

[0026] 2. In this invention, the synergistic process of ultrasonic-assisted dispersion and stirring under vacuum conditions enables the nanoscale antiviral materials and formaldehyde removal catalysts to be fully deagglomerated and uniformly distributed in the emulsion system, avoiding the problem of reduced activity caused by particle aggregation. At the same time, the vacuum environment eliminates air bubbles introduced during stirring. Combined with subsequent fine grinding processes, the storage stability and application smoothness of the finished coating are improved, ensuring that the coating surface is dense and smooth and the functional expression is uniform.

[0027] 3. In this invention, the selected bio-based resins and various functional materials all have excellent compatibility. Through strict raw material activation pretreatment and optimized additive formulation, the interfacial bonding force and synergistic effect between the components are enhanced. This not only ensures that the coating is not prone to delamination and deterioration during storage, but also makes the final coating have excellent adhesion, scrub resistance and long-lasting functional effectiveness, achieving a unity of environmental protection, functionality and durability. Detailed Implementation

[0028] 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.

[0029] Example 1: An antiviral coating capable of continuously releasing negative ions and its preparation method, the method comprising the following steps:

[0030] Step 1: Raw material preparation, selecting bio-based resin, negative ion releasing material, nano antiviral material, formaldehyde removal catalyst, water and additives as basic raw materials;

[0031] Step 2: Premixing treatment. Add bio-based resin and water to a mixing device and stir at 200 r / min for 10 minutes at room temperature to form a uniform emulsion.

[0032] Step 3: Adding functional materials. Add negative ion releasing material, nano antiviral material and formaldehyde removal catalyst to the emulsion obtained in Step 2 in sequence. Control the temperature at 25℃ and stir at 300r / min for 20 minutes to make the materials evenly dispersed.

[0033] Step 4: Additive blending. Add dispersant, defoamer, thickener and preservative to the mixture obtained in Step 3. Increase the stirring speed to 500 r / min and continue stirring for 15 minutes to adjust the viscosity and stability of the coating.

[0034] Step 5: Post-processing. The coating obtained in Step 4 is ground to a fineness of ≤50μm using a grinding equipment, then filtered and packaged to obtain the final antiviral coating.

[0035] In step one, the bio-based resin is at least one of bio-based acrylic resin, epoxy soybean oil resin or polylactic acid resin, with a solid content of 40% and a pH value of 7.5; the negative ion releasing material is at least one of tourmaline powder, negative ion ceramic powder or diatomaceous earth, with a particle size of 3μm; and the nano antiviral material is at least one of nano silver, nano zinc oxide or nano titanium dioxide, with a particle size of 30nm.

[0036] The aldehyde removal catalyst is activated by the following method: the catalyst is placed in a muffle furnace and calcined at 300°C for 2 hours, then immersed in 0.1 mol / L silver nitrate solution or platinum chloride solution for 10 minutes, and then dried.

[0037] The bio-based resin is prepared by the following method: select one of corn starch, soybean oil or plant cellulose as raw material, add the raw material and deionized water to the reaction vessel, the mass ratio of raw material to water is 1:2, control the temperature at 60℃, stir at 100 r / min for 30 minutes, then add 0.1 parts by weight of ammonium persulfate catalyst, raise the temperature to 80℃ and react for 2 hours, cool and adjust the pH to neutral to obtain the bio-based resin emulsion.

[0038] In step two, the premixing treatment includes the following sub-steps: first, heat the water to 30°C, then slowly add the bio-based resin while stirring at a speed of 200 r / min. During the stirring process, ultrasonic-assisted dispersion is used. Ultrasonic-assisted dispersion is achieved through an immersion ultrasonic probe with a frequency of 20 kHz and a power density of 50 W / L. The treatment method is intermittent, i.e., working for 5 seconds followed by a 2-second pause, and the treatment time is 5 minutes to completely emulsify the resin.

[0039] In step three, the functional materials are added in the following order: first, add the negative ion releasing material, stir for 10 minutes, then add the nano antiviral material, continue stirring for 10 minutes, and finally add the formaldehyde removal catalyst. The stirring equipment is a reaction vessel with a temperature control and vacuum system, and the vacuum degree is controlled at -0.05MPa to remove air bubbles.

[0040] The antiviral nanomaterials were prepared by the following method: silver nitrate, zinc sulfate or tetrabutyl titanate were selected as the precursors, dissolved in deionized water at a concentration of 0.1 mol / L, and 0.1 parts by weight of sodium citrate stabilizer were added. The mixture was stirred at 500 r / min for 1 hour at 60℃, and then nanoparticles were synthesized by precipitation or sol-gel method.

[0041] When synthesizing by precipitation method, a precipitant sodium hydroxide or sodium carbonate solution with a concentration of 0.5 mol / L is slowly added dropwise to the above precursor solution, with the dropping rate controlled at 1 mL / min, until the pH value of the solution reaches 8, and then the mixture is stirred and matured for 1 hour.

[0042] When synthesizing using the sol-gel method, nitric acid or ammonia, accounting for 5% of the molar amount of the precursor, is added to the above precursor solution and aged at 40°C for 12 hours to form a sol. Then, the temperature is raised to 60°C and aged for another 24 hours to transform it into a gel.

[0043] The products obtained by precipitation or sol-gel methods were centrifuged, washed and dried to obtain nanomaterials with a particle size of 10 nm. The centrifugation speed was 8000 rpm and the time was 10 minutes. The washing was carried out by alternating washing with deionized water and anhydrous ethanol twice each. The drying was carried out in a vacuum drying oven at 60°C for 2 hours.

[0044] In step four, the additives include dispersants, defoamers, thickeners, and preservatives. The dispersant is at least one of polyvinylpyrrolidone or sodium polyacrylate, added at 0.5 parts by weight. The defoamer is at least one of silicone defoamers or mineral oil defoamers, added at 0.1 parts by weight. The thickener is at least one of hydroxyethyl cellulose or polyurethane thickeners, added at 0.3 parts by weight. The preservative is at least one of isothiazolinone or benzisothiazolinone, added at 0.1 parts by weight.

[0045] In step five, the grinding equipment is a sand mill or ball mill, the grinding media is zirconia beads with a diameter of 0.5 mm, and the grinding time is 30 minutes; the filtration uses a 200-mesh sieve, the filtration pressure is 0.1 MPa, and the resulting coating has a viscosity of 80 KU and a fineness of ≤50 μm.

[0046] The coating is composed of the following raw materials in parts by weight: 30 parts of bio-based resin, 5 parts of negative ion releasing material, 1 part of nano antiviral material, 5 parts of formaldehyde removal catalyst, 20 parts of water, and 1 part of additives. The formaldehyde removal catalyst is at least one of photocatalyst titanium dioxide, manganese-based catalyst, or molecular sieve catalyst, with a specific surface area ≥100m² / g.

[0047] Example 2: An antiviral coating capable of continuously releasing negative ions and its preparation method, the method comprising the following steps:

[0048] Step 1: Raw material preparation, selecting bio-based resin, negative ion releasing material, nano antiviral material, formaldehyde removal catalyst, water and additives as basic raw materials;

[0049] Step 2: Premixing treatment. Add bio-based resin and water to a mixing device and stir at 350 r / min for 15 minutes at room temperature to form a uniform emulsion.

[0050] Step 3: Adding functional materials. Add negative ion releasing material, nano antiviral material and formaldehyde removal catalyst to the emulsion obtained in Step 2 in sequence. Control the temperature at 30℃ and stir at 450r / min for 30 minutes to make the materials evenly dispersed.

[0051] Step 4: Additive blending. Add dispersant, defoamer, thickener and preservative to the mixture obtained in Step 3. Increase the stirring speed to 800 r / min and continue stirring for 25 minutes to adjust the viscosity and stability of the coating.

[0052] Step 5: Post-processing. The coating obtained in Step 4 is ground to a fineness of ≤50μm using a grinding equipment, then filtered and packaged to obtain the final antiviral coating.

[0053] In step one, the bio-based resin is at least one of bio-based acrylic resin, epoxy soybean oil resin or polylactic acid resin, with a solid content of 50% and a pH value of 8.5; the negative ion releasing material is at least one of tourmaline powder, negative ion ceramic powder or diatomaceous earth, with a particle size of 6μm; and the nano antiviral material is at least one of nano silver, nano zinc oxide or nano titanium dioxide, with a particle size of 60nm.

[0054] The aldehyde removal catalyst was activated by the following method: the catalyst was placed in a muffle furnace and calcined at 400°C for 3 hours, then immersed in 0.3 mol / L silver nitrate solution or platinum chloride solution for 20 minutes, and then dried.

[0055] The bio-based resin is prepared by the following method: select one of corn starch, soybean oil or plant cellulose as raw material, add the raw material and deionized water to the reaction vessel, the mass ratio of raw material to water is 1:3, control the temperature at 70℃, stir at 200 r / min for 45 minutes, then add 0.3 parts by weight of ammonium persulfate catalyst, raise the temperature to 90℃ and react for 3 hours, cool and adjust the pH to neutral to obtain the bio-based resin emulsion.

[0056] In step two, the premixing treatment includes the following sub-steps: first, heat the water to 35°C, then slowly add the bio-based resin while stirring at a speed of 350 r / min. During the stirring process, ultrasonic-assisted dispersion is used. Ultrasonic-assisted dispersion is achieved through an immersion ultrasonic probe with a frequency of 30 kHz and a power density of 100 W / L. The treatment method is intermittent, i.e., working for 7 seconds followed by a 3-second pause, and the treatment time is 10 minutes to completely emulsify the resin.

[0057] In step three, the functional materials are added in the following order: first, add the negative ion releasing material, stir for 12 minutes, then add the nano antiviral material, continue stirring for 12 minutes, and finally add the formaldehyde removal catalyst. The stirring equipment is a reaction vessel with a temperature control and vacuum system, and the vacuum degree is controlled at -0.08MPa to remove air bubbles.

[0058] The antiviral nanomaterials were prepared by the following method: silver nitrate, zinc sulfate or tetrabutyl titanate were selected as the precursors, dissolved in deionized water at a concentration of 0.3 mol / L, and 0.2 parts by weight of sodium citrate stabilizer were added. The mixture was stirred at 800 r / min for 1.5 hours at 70 °C, and then nanoparticles were synthesized by precipitation or sol-gel method.

[0059] When synthesizing by precipitation method, a precipitant sodium hydroxide or sodium carbonate solution with a concentration of 1.0 mol / L is slowly added dropwise to the above precursor solution, with the dropping rate controlled at 2 mL / min, until the pH value of the solution reaches 10, and then the mixture is stirred and matured for 2 hours.

[0060] When synthesizing using the sol-gel method, nitric acid or ammonia, accounting for 10% of the molar amount of the precursor, is added to the above precursor solution and aged at 50°C for 24 hours to form a sol. Then, the temperature is raised to 70°C and aged for another 36 hours to transform it into a gel.

[0061] The products obtained by precipitation or sol-gel methods were centrifuged, washed and dried to obtain nanomaterials with a particle size of 60 nm. The centrifugation speed was 10,000 rpm and the time was 15 minutes. The washing was carried out by alternating between deionized water and anhydrous ethanol twice each. The drying was carried out in a vacuum drying oven at 70 °C for 3 hours.

[0062] In step four, the additives include dispersants, defoamers, thickeners, and preservatives. The dispersant is at least one of polyvinylpyrrolidone or sodium polyacrylate, with an addition amount of 1.0 part by weight. The defoamer is at least one of silicone defoamers or mineral oil defoamers, with an addition amount of 0.3 parts by weight. The thickener is at least one of hydroxyethyl cellulose or polyurethane thickener, with an addition amount of 0.6 parts by weight. The preservative is at least one of isothiazolinone or benzisothiazolinone, with an addition amount of 0.2 parts by weight.

[0063] In step five, the grinding equipment is a sand mill or a ball mill, the grinding media is zirconia beads with a diameter of 0.7 mm, and the grinding time is 45 minutes; the filtration uses a 300-mesh sieve, the filtration pressure is 0.2 MPa, and the resulting coating has a viscosity of 100 KU and a fineness of ≤50 μm.

[0064] The coating is composed of the following raw materials in parts by weight: 40 parts of bio-based resin, 10 parts of negative ion releasing material, 3 parts of nano antiviral material, 7 parts of formaldehyde removal catalyst, 30 parts of water, and 3 parts of additives. The formaldehyde removal catalyst is at least one of photocatalyst titanium dioxide, manganese-based catalyst, or molecular sieve catalyst, with a specific surface area ≥100m² / g.

[0065] Example 3: An antiviral coating capable of continuously releasing negative ions and its preparation method, the method comprising the following steps:

[0066] Step 1: Raw material preparation, selecting bio-based resin, negative ion releasing material, nano antiviral material, formaldehyde removal catalyst, water and additives as basic raw materials;

[0067] Step 2: Premixing treatment. Add bio-based resin and water to a mixing device and stir at 500 r / min for 20 minutes at room temperature to form a uniform emulsion.

[0068] Step 3: Adding functional materials. Add negative ion releasing material, nano antiviral material and formaldehyde removal catalyst to the emulsion obtained in Step 2 in sequence. Control the temperature at 35℃ and stir at 600r / min for 40 minutes to make the materials evenly dispersed.

[0069] Step 4: Additive blending. Add dispersant, defoamer, thickener and preservative to the mixture obtained in Step 3. Increase the stirring speed to 1000 r / min and continue stirring for 30 minutes to adjust the viscosity and stability of the coating.

[0070] Step 5: Post-processing. The coating obtained in Step 4 is ground to a fineness of ≤50μm using a grinding equipment, then filtered and packaged to obtain the final antiviral coating.

[0071] In step one, the bio-based resin is at least one of bio-based acrylic resin, epoxy soybean oil resin or polylactic acid resin, with a solid content of 60% and a pH value of 9.0; the negative ion releasing material is at least one of tourmaline powder, negative ion ceramic powder or diatomaceous earth, with a particle size of 10μm; and the nano antiviral material is at least one of nano silver, nano zinc oxide or nano titanium dioxide, with a particle size of 100nm.

[0072] The aldehyde removal catalyst is activated by the following method: the catalyst is placed in a muffle furnace and calcined at 500°C for 4 hours, then immersed in 0.5 mol / L silver nitrate solution or platinum chloride solution for 30 minutes, and then dried.

[0073] The bio-based resin is prepared by the following method: select one of corn starch, soybean oil or plant cellulose as raw material, add the raw material and deionized water to the reaction vessel, the mass ratio of raw material to water is 1:4, control the temperature at 80℃, stir at 300r / min for 60 minutes, then add 0.5 parts by weight of ammonium persulfate catalyst, raise the temperature to 100℃ and react for 4 hours, cool and adjust the pH to neutral to obtain the bio-based resin emulsion.

[0074] In step two, the premixing treatment includes the following sub-steps: first, heat the water to 40°C, then slowly add the bio-based resin while stirring at a speed of 500 r / min. During the stirring process, ultrasonic-assisted dispersion is used. Ultrasonic-assisted dispersion is achieved through an immersion ultrasonic probe with a frequency of 40 kHz and a power density of 150 W / L. The treatment method is intermittent, i.e., working for 10 seconds followed by a 5-second pause, and the treatment time is 15 minutes to completely emulsify the resin.

[0075] In step three, the functional materials are added in the following order: first, add the negative ion releasing material, stir for 15 minutes, then add the nano antiviral material, continue stirring for 15 minutes, and finally add the formaldehyde removal catalyst. The stirring equipment is a reaction vessel with a temperature control and vacuum system, and the vacuum degree is controlled at -0.1MPa to remove air bubbles.

[0076] The antiviral nanomaterials were prepared by the following method: silver nitrate, zinc sulfate or tetrabutyl titanate were selected as the precursors, dissolved in deionized water at a concentration of 0.5 mol / L, and 0.3 parts by weight of sodium citrate stabilizer were added. The mixture was stirred at 1000 r / min for 2 hours at 80℃, and then nanoparticles were synthesized by precipitation or sol-gel method.

[0077] When synthesizing by precipitation method, a precipitant sodium hydroxide or sodium carbonate solution with a concentration of 1.5 mol / L is slowly added dropwise to the above precursor solution, with the addition rate controlled at 3 mL / min, until the pH value of the solution reaches 11, and then the mixture is stirred and matured for 3 hours.

[0078] When synthesizing using the sol-gel method, nitric acid or ammonia, accounting for 15% of the molar amount of the precursor, is added to the above precursor solution and aged at 60°C for 48 hours to form a sol. Then, the temperature is raised to 80°C and aged for another 72 hours to transform it into a gel.

[0079] The products obtained by precipitation or sol-gel methods were centrifuged, washed and dried to obtain nanomaterials with a particle size of 100 nm. The centrifugation speed was 12000 rpm and the time was 20 minutes. The washing was carried out by alternating washing with deionized water and anhydrous ethanol 3 times each. The drying was carried out in a vacuum drying oven at 80℃ for 4 hours.

[0080] In step four, the additives include dispersants, defoamers, thickeners, and preservatives. The dispersant is at least one of polyvinylpyrrolidone or sodium polyacrylate, and the amount added is 1.5 parts by weight. The defoamer is at least one of silicone defoamer or mineral oil defoamer, and the amount added is 0.5 parts by weight. The thickener is at least one of hydroxyethyl cellulose or polyurethane thickener, and the amount added is 1.0 part by weight. The preservative is at least one of isothiazolinone or benzisothiazolinone, and the amount added is 0.3 parts by weight.

[0081] In step five, the grinding equipment is a sand mill or a ball mill, the grinding media is zirconia beads with a diameter of 1.0 mm, and the grinding time is 60 minutes; the filtration uses a 400-mesh sieve, the filtration pressure is 0.3 MPa, and the resulting coating has a viscosity of 120 KU and a fineness of ≤50 μm.

[0082] The coating is composed of the following raw materials in parts by weight: 50 parts of bio-based resin, 15 parts of negative ion releasing material, 5 parts of nano antiviral material, 10 parts of formaldehyde removal catalyst, 40 parts of water, and 5 parts of additives. The formaldehyde removal catalyst is at least one of photocatalyst titanium dioxide, manganese-based catalyst, or molecular sieve catalyst, with a specific surface area ≥100m² / g.

[0083] Comparative Example 1: The difference between this comparative example and Example 1 is that no negative ion releasing material was added when preparing the coating in this comparative example.

[0084] Comparative Example 2 differs from Example 1 in that no nano-antiviral materials were added during the preparation of the coating in this comparative example.

[0085] Comparative Example 3 differs from Example 1 in that the formaldehyde removal catalyst was not activated during the preparation of the coating in this comparative example.

[0086] Comparative Example 4 differs from Example 1 in that vacuum mixing was not used in this comparative example.

[0087] The antiviral coatings capable of continuously releasing negative ions prepared in Examples 1-3 and Comparative Examples 1-4 were subjected to performance tests. The test items and test methods are as follows:

[0088] For the negative ion release test, in a closed environment chamber at a temperature of 23±2℃ and a relative humidity of 50±5%, after the coated sample was placed for 24 hours, the negative ion concentration in the chamber was measured using an air negative ion detector, and the negative ion release per unit area was calculated.

[0089] Antiviral performance test: Under the conditions of temperature 20±2℃ and relative humidity 50±5%, a virus suspension of a specified concentration was dropped onto the coating surface. After a specified time, the residual liquid was collected and the virus titer was measured to calculate the antiviral rate.

[0090] Formaldehyde purification performance test: In a 1 cubic meter environmental chamber, formaldehyde gas of a specified initial concentration is injected. Under the conditions of temperature 23±2℃, relative humidity 50±5%, and light, the formaldehyde concentration in the chamber is monitored for 24 hours, and the formaldehyde purification efficiency is calculated.

[0091] For adhesion testing, the cross-cut test is used. A grid is formed on the coating surface using a cutter with a cutting interval of 1 mm or 2 mm. Pressure-sensitive adhesive tape is then applied and quickly peeled off. The adhesion is evaluated based on the grid peeling level.

[0092] The scrub resistance test involves fixing the sample on a scrub tester, using a scrubbing medium of a specified concentration and a specific brush, and repeatedly scrubbing the coating surface under a certain load, recording the number of scrubbing cycles until the substrate is exposed.

[0093] The test data of the antiviral coatings prepared in Examples 1-3 and Comparative Examples 1-4 are recorded in the table below:

[0094] Testing items Negative ion release (ions / s·cm²) Antiviral rate (%) Formaldehyde purification rate (%) Adhesion (Grade) Washability (times) Example 1 482±25 99.8 92.5 0 12500 Example 2 468±22 99.5 90.8 0 11800 Example 3 495±30 99.9 93.1 0 13000 Comparative Example 1 85±15 99.7 91.0 1 9800 Comparative Example 2 475±20 30.5 89.5 1 10200 Comparative Example 3 490±28 99.6 65.3 0 12300 Comparative Example 4 455±40 98.5 88.9 2 8500

[0095] Comparison and analysis of the data in the table show that the antiviral coatings prepared using the methods in Examples 1-3 exhibit superior performance in all aspects compared to the coatings obtained in Comparative Examples 1-4. This indicates that the combination of bio-based resin with negative ion releasing materials, nano-antiviral materials, and formaldehyde removal catalysts under specific process conditions provides a stable carrier for the functional materials through a continuous phase formed by the bio-based resin, enabling them to be uniformly dispersed and firmly bonded. The negative ion releasing materials, protected by the resin system, can continuously and stably release negative ions into the environment. The nano-antiviral materials and formaldehyde removal catalysts work synergistically on the coating surface and within the coating to jointly construct a long-lasting antiviral and formaldehyde-purifying functional layer, thus achieving the long-lasting and stable multifunctionality of the coating. The synergistic process of ultrasonic-assisted dispersion and stirring under vacuum conditions allows the nanoscale antiviral materials and formaldehyde removal catalysts to fully deagglomerate and uniformly distribute in the emulsion system, avoiding the problem of reduced activity caused by particle aggregation. Simultaneously, the vacuum environment eliminates air bubbles introduced during stirring. Combined with subsequent fine grinding processes, this improves the storage stability and application smoothness of the finished coating, ensuring a dense and smooth coating surface and uniform functional expression. The selected bio-based resins and various functional materials all have excellent compatibility. Through strict raw material activation pretreatment and optimized additive formulation, the interfacial bonding and synergistic effect between the components are enhanced. This not only ensures that the coating is not prone to delamination and deterioration during storage, but also makes the final coating have excellent adhesion, scrub resistance and long-lasting functional effectiveness, achieving a unity of environmental protection, functionality and durability.

[0096] By comparing and analyzing the relevant data in the table, it can be seen that the antiviral coating prepared by the method of the present invention not only has excellent negative ion release function and efficient antiviral and formaldehyde purification capabilities, but also has good adhesion and washability. This indicates that the antiviral coating capable of continuously releasing negative ions and its preparation method provided by the present invention have excellent comprehensive performance.

[0097] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0098] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for preparing an antiviral coating capable of continuously releasing negative ions, characterized in that: The method includes the following steps: Step 1: Raw material preparation, selecting bio-based resin, negative ion releasing material, nano antiviral material, formaldehyde removal catalyst, water and additives as basic raw materials; Step 2: Premixing treatment. Add bio-based resin and water to a mixing device and stir at 200-500 r / min for 10-20 minutes at room temperature to form a uniform emulsion. Step 3: Add functional materials. Add negative ion releasing material, nano antiviral material and formaldehyde removal catalyst to the emulsion obtained in Step 2 in sequence. Control the temperature at 25-35℃ and stir at 300-600r / min for 20-40 minutes to make the materials evenly dispersed. Step 4: Additive blending. Add dispersant, defoamer, thickener and preservative to the mixture obtained in Step 3. Increase the stirring speed to 500-1000 r / min and continue stirring for 15-30 minutes to adjust the viscosity and stability of the coating. Step 5: Post-processing. The coating obtained in Step 4 is ground to a fineness of ≤50μm using a grinding equipment, then filtered and packaged to obtain the final antiviral coating.

2. The method for preparing an antiviral coating capable of continuously releasing negative ions according to claim 1, characterized in that: In step one, the bio-based resin is at least one of bio-based acrylic resin, epoxy soybean oil resin, or polylactic acid resin, with a solid content of 40%-60% and a pH value of 7.5-9.0; the negative ion releasing material is at least one of tourmaline powder, negative ion ceramic powder, or diatomaceous earth, with a particle size range of 1-10 μm; and the nano antiviral material is at least one of nano silver, nano zinc oxide, or nano titanium dioxide, with a particle size range of 10-100 nm.

3. The method for preparing an antiviral coating capable of continuously releasing negative ions according to claim 1, characterized in that: The aldehyde removal catalyst is activated by the following method: the catalyst is placed in a muffle furnace and calcined at 300-500℃ for 2-4 hours, then soaked in 0.1-0.5mol / L silver nitrate solution or platinum chloride solution for 10-30 minutes, and then dried.

4. The method for preparing an antiviral coating capable of continuously releasing negative ions according to claim 2, characterized in that: The bio-based resin is prepared by the following method: select one of corn starch, soybean oil or plant cellulose as raw material, add the raw material and deionized water to a reaction vessel, the mass ratio of raw material to water is 1:2-1:4, control the temperature at 60-80℃, stir at 100-300r / min for 30-60 minutes, then add 0.1-0.5 parts by weight of ammonium persulfate catalyst, heat to 80-100℃ and react for 2-4 hours, cool and adjust the pH to neutral to obtain bio-based resin emulsion.

5. The method for preparing an antiviral coating capable of continuously releasing negative ions according to claim 1, characterized in that: In step two, the premixing treatment includes the following sub-steps: first, heat the water to 30-40℃, then slowly add the bio-based resin while stirring at a speed of 200-500 r / min. During the stirring process, ultrasonic-assisted dispersion is used. The ultrasonic-assisted dispersion is achieved by an immersion ultrasonic probe with a frequency of 20-40 kHz and a power density of 50-150 W / L. The treatment method is intermittent, that is, working for 5-10 seconds and then pausing for 2-5 seconds, with a treatment time of 5-15 minutes, to completely emulsify the resin.

6. The method for preparing an antiviral coating capable of continuously releasing negative ions according to claim 1, characterized in that: In step three, the order of adding functional materials is as follows: first add the negative ion releasing material, stir for 10-15 minutes, then add the nano antiviral material, continue stirring for 10-15 minutes, and finally add the formaldehyde removal catalyst; the stirring equipment is a reaction vessel with a temperature control and vacuum system, and the vacuum degree is controlled at -0.05 to -0.1 MPa to remove bubbles.

7. The method for preparing an antiviral coating capable of continuously releasing negative ions according to claim 6, characterized in that: The nano-antiviral material is prepared by the following method: silver nitrate, zinc sulfate or tetrabutyl titanate is selected as a precursor, dissolved in deionized water at a concentration of 0.1-0.5 mol / L, and sodium citrate stabilizer is added at 0.1-0.3 parts by weight. The mixture is stirred at 500-1000 r / min for 1-2 hours at 60-80℃, and then nanoparticles are synthesized by precipitation or sol-gel method. When synthesizing by precipitation method, slowly add a precipitant sodium hydroxide or sodium carbonate solution with a concentration of 0.5-1.5 mol / L to the above precursor solution, controlling the adding rate to 1-3 mL / min, until the pH value of the solution reaches 8-11, and continue stirring and maturing for 1-3 hours; When synthesizing using the sol-gel method, nitric acid or ammonia, accounting for 5%-15% of the molar amount of the precursor, is added to the above precursor solution and aged at 40-60℃ for 12-48 hours to form a sol. Then, the temperature is raised to 60-80℃ and the aging continues for 24-72 hours to transform it into a gel. The products obtained by the precipitation method or sol-gel method are centrifuged, washed and dried to obtain nanomaterials with a particle size of 10-100 nm. The centrifugation speed is 8000-12000 rpm and the time is 10-20 minutes. The washing is performed by alternating between deionized water and anhydrous ethanol 2-3 times each. The drying is carried out in a vacuum drying oven at a temperature of 60-80℃ for 2-4 hours.

8. The method for preparing an antiviral coating capable of continuously releasing negative ions according to claim 1, characterized in that: In step four, the additives include dispersants, defoamers, thickeners, and preservatives. The dispersant is at least one of polyvinylpyrrolidone or sodium polyacrylate, added at 0.5-1.5 parts by weight. The defoamer is at least one of silicone defoamers or mineral oil defoamers, added at 0.1-0.5 parts by weight. The thickener is at least one of hydroxyethyl cellulose or polyurethane thickener, added at 0.3-1.0 parts by weight. The preservative is at least one of isothiazolinone or benzisothiazolinone, added at 0.1-0.3 parts by weight.

9. The method for preparing an antiviral coating capable of continuously releasing negative ions according to claim 1, characterized in that: In step five, the grinding equipment is a sand mill or a ball mill, the grinding media is zirconia beads with a diameter of 0.5-1.0 mm, and the grinding time is 30-60 minutes; the filtration uses a 200-400 mesh screen, the filtration pressure is 0.1-0.3 MPa, and the viscosity of the coating is 80-120 KU with a fineness ≤50 μm.

10. An antiviral coating capable of continuously releasing negative ions, prepared by the method for preparing an antiviral coating capable of continuously releasing negative ions as described in any one of claims 1-9, characterized in that: The coating is composed of the following raw materials in parts by weight: 30-50 parts of bio-based resin, 5-15 parts of negative ion releasing material, 1-5 parts of nano antiviral material, 5-10 parts of formaldehyde removal catalyst, 20-40 parts of water, and 1-5 parts of additives; the formaldehyde removal catalyst is at least one of photocatalyst titanium dioxide, manganese-based catalyst, or molecular sieve catalyst, with a specific surface area ≥100m² / g.