Preparation method of antibacterial powder coating
By adding modified silica sol and benzalkonium bromide to the powder coating, combined with antibacterial agents, the problems of poor adhesion and lack of antibacterial function of traditional powder coatings are solved, and the dense surface structure and sustained-release antibacterial effect of thermoset powder coatings are achieved. .
Patent Information
- Application Number
- CN202411470274.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-21
- Publication Date
- 2025-01-03
AI Technical Summary
Traditional powder coatings have poor adhesion and do not have antibacterial functions, so they cannot meet the needs of sprayed objects with high antibacterial requirements.
The mixture of polyurethane resin and polyethyleneimine is used as the matrix resin solution, and the polyammonium carboxylate dispersant, isoamino sulfate, silica sol and benzalkonium bromide are added to it, and the components such as ball milling and ultrasonic treatment are carried out. A modified silica sol is formed, combined with benzapine bromide and an antibacterial agent, and an antibacterial powder coating is prepared by spray drying.
The chemical cross-linking curing of thermoset powder coatings is achieved, forming a dense surface structure, with sustained release antibacterial effect, and significantly improving the antibacterial properties of powder coatings.
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of powder coating preparation, and in particular to a method for preparing an antibacterial powder coating. Background Art
[0002] Powder coating is a solid powdered synthetic resin coating composed of solid resin, pigment, filler and additives. Unlike ordinary solvent-based coatings and water-based coatings, its dispersion medium is not solvent and water, but air. It has the characteristics of no solvent pollution, 100% film formation and low energy consumption.
[0003] However, traditional powder coatings are mostly thermoplastic powder coatings, which have poor adhesion to metals and do not have antibacterial properties. They cannot meet the use requirements of some objects to be sprayed with high antibacterial requirements. Summary of the invention
[0004] The purpose of the present invention is to solve the shortcomings of the conventional powder coating in the prior art, that is, the conventional powder coating has poor adhesion and lacks antibacterial function.
[0005] In order to achieve the above object, the present invention adopts the following technical scheme: a method for preparing an antibacterial powder coating, comprising the following steps: a: Mix polyurethane resin and polyethyleneimine in a mass ratio of 7-9:1, add them into an organic solvent, and prepare a matrix resin liquid after fully dissolving; b: Add 1-5 parts by weight of a polycarboxylate ammonium salt dispersant to deionized water and stir evenly, then add 20 parts by weight of p-methyl-m-hydroxydiphenylamine and 30 parts by weight of isoaminophenol sulfate, stir evenly, dropwise add isopropanolamine to adjust the pH value to 8.5-9, and then grind with a ball mill to obtain a dispersion; c: adding the silica sol to the dispersion prepared in step b under stirring, and mixing thoroughly to obtain a modified silica sol, wherein the silica sol has a silica mass fraction of 30%, a colloidal particle size of 5-12 nm, and a pH of 8.5-9; d: Mix benzalkonium bromide and deionized water in a ratio of 1-3:10 until dissolved; then add the modified silica sol prepared in step c under stirring, and stir thoroughly until the solution becomes a white paste; e: drying the white paste obtained in step d in a drying oven to obtain a white powder, grinding the powder, and subjecting it to ultrasonic treatment for 30-40 minutes to obtain an antibacterial agent; f: By weight, 60-65 parts by weight of base resin liquid, 3-8 parts by weight of antibacterial agent, 4-7 parts by weight of pigment, 2-5 parts by weight of cellulose acetate butyrate, and 1-2 parts by weight of melamine are mixed, added to a high-speed disperser, and then spray-dried to obtain a finished product.
[0006] In at least some embodiments, the organic solution in step a of the method for preparing the matrix resin liquid is any one of methyl acetate, toluene, and ether.
[0007] In at least some embodiments, in step c of the method for preparing the antibacterial agent, the ratio of the benzalkonium bromide solution to the modified silica sol is 2:3-6.
[0008] In at least some embodiments, in step e of the method for preparing the antibacterial agent, the temperature of the drying oven is 65-85° C., and the drying time is 25-40 hours.
[0009] In at least some embodiments, in step e of the method for preparing the antibacterial agent, the white powder is ground to a particle size of 50-70 μm.
[0010] In at least some embodiments, during the ultrasonic treatment in step e of the method for preparing the antibacterial agent, the frequency of the ultrasonic wave is 32-36 khz.
[0011] In at least some embodiments, the pigment in step f is any one of azo pigments.
[0012] Compared with the prior art, the advantages and positive effects of the present invention are: In the present invention, the coating adopts a thermosetting method to prepare a powder coating, which is solidified into a flat and hard coating film after chemical cross-linking, and the added benzalkonium bromide, silica sol and antibacterial agent are combined to effectively ensure that during the drying process of the antibacterial agent, the benzalkonium bromide hinders the condensation of the colloid in the silica sol to produce pores, and the pores are filled with the antibacterial agent so that the antibacterial agent forms a denser surface structure at the microscopic level, so that when the powder coating is sprayed and formed, the coating has a slow-release antibacterial effect. DETAILED DESCRIPTION
[0013] In order to more clearly understand the above-mentioned purpose, features and advantages of the present invention, the present invention is further described below in conjunction with the accompanying drawings and embodiments. It should be noted that the embodiments of the present application and the features in the embodiments can be combined with each other without conflict.
[0014] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways than those described herein. Therefore, the present invention is not limited to the specific embodiments of the following disclosure.
[0015] In an embodiment of the present invention, a method for preparing an antibacterial powder coating is disclosed, comprising the following steps: a: Mix polyurethane resin and polyethyleneimine in a mass ratio of 7-9:1, add them into an organic solvent, and prepare a matrix resin liquid after fully dissolving; b: Add 1-5 parts by weight of a polycarboxylate ammonium salt dispersant to deionized water and stir evenly, then add 20 parts by weight of p-methyl-m-hydroxydiphenylamine and 30 parts by weight of isoaminophenol sulfate, stir evenly, dropwise add isopropanolamine to adjust the pH value to 8.5-9, and then grind with a ball mill to obtain a dispersion; c: adding the silica sol to the dispersion prepared in step b under stirring, and mixing thoroughly to obtain a modified silica sol, wherein the silica sol has a silica mass fraction of 30%, a colloidal particle size of 5-12 nm, and a pH of 8.5-9; d: Mix benzalkonium bromide and deionized water in a ratio of 1-3:10 until dissolved; then add the modified silica sol prepared in step c under stirring, and stir thoroughly until the solution becomes a white paste; e: drying the white paste obtained in step d in a drying oven to obtain a white powder, grinding the powder, and subjecting it to ultrasonic treatment for 30-40 minutes to obtain an antibacterial agent; f: By weight, 60-65 parts by weight of base resin liquid, 3-8 parts by weight of antibacterial agent, 4-7 parts by weight of pigment, 2-5 parts by weight of cellulose acetate butyrate, and 1-2 parts by weight of melamine are mixed, added to a high-speed disperser, and then spray-dried to obtain a finished product.
[0016] The organic solution in step a of the method for preparing the matrix resin liquid is any one of methyl acetate, toluene and ether.
[0017] In step c of the antibacterial agent preparation method, the ratio of benzalkonium bromide solution to modified silica sol is 2:3-6.
[0018] In step e of the method for preparing the antibacterial agent, the temperature of the drying oven is 65-85° C., and the drying time is 25-40 hours.
[0019] In step e of the method for preparing the antibacterial agent, the white powder is ground to a particle size of 50-70 μm.
[0020] During the ultrasonic treatment in step e of the method for preparing the antibacterial agent, the frequency of the ultrasonic wave is 32-36 khz.
[0021] The pigment in step f is any one of azo pigments.
[0022] Example 1 A method for preparing an antibacterial powder coating provided by an embodiment of the present invention comprises: a: After mixing polyurethane resin and polyethyleneimine in a mass ratio of 7:1, adding them into an organic solvent, fully dissolving them to obtain a matrix resin liquid for later use, and the amount of organic solvent added is 10 times the total mass of the polyurethane resin and polyethyleneimine; b: Add 1 part by weight of a polycarboxylate ammonium salt dispersant to 80 parts by weight of deionized water and stir evenly, then add 20 parts by weight of p-methyl-m-hydroxydiphenylamine and 30 parts by weight of isoaminophenol sulfate, stir evenly, dropwise add isopropanolamine to adjust the pH value to 8.5, and then grind by a ball mill to obtain a dispersion; c: adding the silica sol to the dispersion prepared in step b under stirring, and mixing thoroughly to obtain a modified silica sol, wherein the silica sol has a silica mass fraction of 30%, a colloidal particle size of 5 nm, a pH of 8.5, and a mass ratio of the silica sol to the dispersion of 1:3; d: Mix benzalkonium bromide and deionized water in a ratio of 1:10 until dissolved; then add the modified silica sol prepared in step c under stirring, and stir thoroughly until the solution becomes a white paste; e: drying the white paste obtained in step d in a drying oven to obtain a white powder, grinding the powder, and subjecting it to ultrasonic treatment for 30 minutes to obtain an antibacterial agent; f: By weight, 60 parts by weight of base resin liquid, 3 parts by weight of antibacterial agent, 4 parts by weight of pigment, 2 parts by weight of cellulose acetate butyrate and 1 part by weight of melamine are mixed, added to a high-speed disperser, and then spray-dried to obtain a finished product.
[0023] The organic solution in step a of the method for preparing the matrix resin liquid is methyl acetate.
[0024] In step c of the antibacterial agent preparation method, the ratio of benzalkonium bromide solution to modified silica sol is 2:3.
[0025] In step e of the method for preparing the antibacterial agent, the drying oven temperature is 65° C. and the drying time is 25 hours.
[0026] In step e of the method for preparing the antibacterial agent, the white powder is ground to a particle size of 50 μm.
[0027] During the ultrasonic treatment in step e of the method for preparing the antibacterial agent, the frequency of the ultrasonic wave is 32 khz.
[0028] The pigment in step f is golden red.
[0029] Example 2 A method for preparing an antibacterial powder coating provided by an embodiment of the present invention comprises the following steps: a: After mixing polyurethane resin and polyethyleneimine in a mass ratio of 9:1, add them into an organic solvent, fully dissolve them to obtain a matrix resin liquid for later use, and the amount of organic solvent added is 10 times the total mass of the polyurethane resin and polyethyleneimine; b: Add 5 parts by weight of a polycarboxylate ammonium salt dispersant to 80 parts by weight of deionized water and stir evenly, then add 20 parts by weight of p-methyl-m-hydroxydiphenylamine and 30 parts by weight of isoaminophenol sulfate, stir evenly, dropwise add isopropanolamine to adjust the pH value to 9, and then grind by a ball mill to obtain a dispersion; c: adding the silica sol to the dispersion prepared in step b under stirring, and mixing thoroughly to obtain a modified silica sol, wherein the silica sol has a silica mass fraction of 30%, a colloidal particle size of 12 nm, a pH of 9, and a mass ratio of the silica sol to the dispersion of 1:3; d. Mix benzalkonium bromide and deionized water in a ratio of 3:10 until dissolved; then add the modified silica sol prepared in step c under stirring, and stir thoroughly until the solution becomes a white paste; e) drying the white paste obtained in step d in a drying oven to obtain a white powder, grinding the powder, and subjecting it to ultrasonic treatment for 40 minutes to obtain an antibacterial agent; f: By weight, 65 parts by weight of base resin liquid, 8 parts by weight of antibacterial agent, 7 parts by weight of pigment, 5 parts by weight of cellulose acetate butyrate and 2 parts by weight of melamine are mixed, added to a high-speed disperser, and then spray-dried to obtain a finished product.
[0030] The organic solution in step a of the method for preparing the matrix resin liquid is toluene.
[0031] In step c of the antibacterial agent preparation method, the ratio of benzalkonium bromide solution to modified silica sol is 2:6.
[0032] In step e of the method for preparing the antibacterial agent, the temperature of the drying oven is 65-85° C. and the drying time is 40 hours.
[0033] In step e of the method for preparing the antibacterial agent, the white powder is ground to a particle size of 70 μm.
[0034] During the ultrasonic treatment in step e of the method for preparing the antibacterial agent, the frequency of the ultrasonic wave is 36 khz.
[0035] The pigment in step f is benzidine yellow G.
[0036] Example 3 A method for preparing an antibacterial powder coating provided by an embodiment of the present invention comprises the following steps: a: After mixing polyurethane resin and polyethyleneimine in a mass ratio of 8:1, adding the mixture into an organic solvent, fully dissolving the mixture to obtain a matrix resin solution for later use, wherein the amount of the organic solvent added is 10 times the total mass of the polyurethane resin and polyethyleneimine; b: Add 3 parts by weight of a polycarboxylate ammonium salt dispersant to 80 parts by weight of deionized water and stir evenly, then add 20 parts by weight of p-methyl-m-hydroxydiphenylamine and 30 parts by weight of isoaminophenol sulfate, stir evenly, dropwise add isopropanolamine to adjust the pH value to 8.5, and then grind with a ball mill to obtain a dispersion; c: adding the silica sol to the dispersion prepared in step b under stirring, and mixing thoroughly to obtain a modified silica sol, wherein the silica sol has a silica mass fraction of 30%, a colloidal particle size of 8.5 nm, a pH of 8.5, and a mass ratio of the silica sol to the dispersion of 1:3; d. Mix benzalkonium bromide and deionized water in a ratio of 2:10 until dissolved; then add the modified silica sol prepared in step c under stirring, and stir thoroughly until the solution becomes a white paste; e: drying the white paste obtained in step d in a drying oven to obtain a white powder, grinding the powder, and subjecting it to ultrasonic treatment for 35 minutes to obtain an antibacterial agent; f: By weight, 62 parts by weight of base resin liquid, 6 parts by weight of antibacterial agent, 5.5 parts by weight of pigment, 3.5 parts by weight of cellulose acetate butyrate and 1.5 parts by weight of melamine were mixed, added to a high-speed disperser, and then spray-dried to obtain a finished product.
[0037] The organic solution in step a of the method for preparing the matrix resin liquid is ether.
[0038] In step c of the antibacterial agent preparation method, the ratio of benzalkonium bromide solution to modified silica sol is 2:4.
[0039] In step e of the method for preparing the antibacterial agent, the drying oven temperature is 75° C. and the drying time is 35 hours.
[0040] In step e of the method for preparing the antibacterial agent, the white powder is ground to a particle size of 60 μm.
[0041] During the ultrasonic treatment in step e of the method for preparing the antibacterial agent, the frequency of the ultrasonic wave is 34 khz.
[0042] The pigment in step f is permanent orange RN.
[0043] The antibacterial powder coatings were prepared by the methods of the embodiments, and then sprayed on the surface of the plastic plate. The antibacterial results were tested by JIS2801 standard: Compared with the untreated sample, Example 1 has a significant antibacterial effect; Compared with the untreated sample, the antibacterial effect of Example 2 is weaker than that of Example 1; Compared with the untreated sample, the antibacterial effect of Example 3 is stronger than that of Example 2 and weaker than that of Example 1; Therefore, it can be concluded that benzalkonium bromide hinders the condensation of colloids in the silica sol and produces pores, which are filled with the antibacterial agent to form a denser surface structure at the microscopic level. As a result, when the powder coating is sprayed and formed, the coating has a sustained-release antibacterial effect, and the smaller the pores, the stronger the antibacterial ability. In summary, the antibacterial powder coating of the present invention has greatly improved antibacterial properties compared with ordinary powder coatings and can be promoted and applied.
[0044] The above are only preferred embodiments of the present invention and are not intended to limit the present invention in other forms. Any technician familiar with the profession may use the technical contents disclosed above to change or modify them into equivalent embodiments with equivalent changes and apply them to other fields. However, any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present invention without departing from the technical solution of the present invention still falls within the protection scope of the technical solution of the present invention.
Claims
1. A method for preparing an antibacterial powder coating, characterized in that: The following steps are involved: a: Mix polyurethane resin and polyethyleneimine in a mass ratio of 7-9:1, add them into an organic solvent, and prepare a matrix resin liquid after fully dissolving; b: Add 1-5 parts by weight of a polycarboxylate ammonium salt dispersant to deionized water and stir evenly, then add 20 parts by weight of p-methyl-m-hydroxydiphenylamine and 30 parts by weight of isoaminophenol sulfate, stir evenly, dropwise add isopropanolamine to adjust the pH value to 8.5-9, and then grind with a ball mill to obtain a dispersion; c: adding the silica sol to the dispersion prepared in step b under stirring, and mixing thoroughly to obtain a modified silica sol, wherein the silica sol has a silica mass fraction of 30%, a colloidal particle size of 5-12 nm, and a pH of 8.5-9; d: Mix benzalkonium bromide and deionized water in a ratio of 1-3:10 until dissolved; then add the modified silica sol prepared in step c under stirring, and stir thoroughly until the solution becomes a white paste; e: drying the white paste obtained in step d in a drying oven to obtain a white powder, grinding the powder, and subjecting it to ultrasonic treatment for 30-40 minutes to obtain an antibacterial agent; f: By weight, 60-65 parts by weight of base resin liquid, 3-8 parts by weight of antibacterial agent, 4-7 parts by weight of pigment, 2-5 parts by weight of cellulose acetate butyrate, and 1-2 parts by weight of melamine are mixed, added to a high-speed disperser, and then spray-dried to obtain a finished product.
2. The method for preparing an antibacterial powder coating according to claim 1, characterized in that: The organic solution in step a of the method for preparing the matrix resin liquid is any one of methyl acetate, toluene and ether.
3. The method for preparing an antibacterial powder coating according to claim 1, characterized in that: In step c of the antibacterial agent preparation method, the ratio of benzalkonium bromide solution to modified silica sol is 2:3-6.
4. The method for preparing an antibacterial powder coating according to claim 1, characterized in that: In step e of the method for preparing the antibacterial agent, the temperature of the drying oven is 65-85° C., and the drying time is 25-40 hours.
5. The method for preparing an antibacterial powder coating according to claim 1, characterized in that: In step e of the method for preparing the antibacterial agent, the white powder is ground to a particle size of 50-70 μm.
6. The method for preparing an antibacterial powder coating according to claim 1, characterized in that: During the ultrasonic treatment in step e of the method for preparing the antibacterial agent, the frequency of the ultrasonic wave is 32-36 khz.
7. The method for preparing an antibacterial powder coating according to claim 1, characterized in that: The pigment in step f is any one of azo pigments.