A dual-coordination sustained-release antibacterial and antireflective coating and its preparation method

Abstract

The present invention relates to the technical field of functional anti-reflective coatings, and in particular to a dual-coordinate sustained-release antibacterial anti-reflective coating and a preparation method thereof. The dual-coordinate sustained-release antibacterial anti-reflective coating comprises a dual-coordinate sustained-release antibacterial layer and a bottom layer, wherein the dual-coordinate sustained-release antibacterial layer is wrapped around the outer surface of the bottom layer; the dual-coordinate sustained-release antibacterial layer comprises, from the inside to the outside, an inner coordination layer, an antibacterial active layer, and an outer coordination layer; the inner coordination layer is composed of polydopamine, the antibacterial active layer is composed of metal ions, the outer coordination layer is composed of phytic acid, and the bottom layer is composed of inorganic nanoparticles. The preparation method comprises preparing the bottom layer, the inner coordination layer, the antibacterial active layer, and the outer coordination layer. The preparation process is simple, easy to operate, the reaction conditions are mild, and the coating is suitable for large-scale production. The dual-coordinate sustained-release antibacterial anti-reflective coating provided by the present invention has stronger antibacterial activity and a long-lasting antibacterial effect than a single-coordinate antibacterial reflective coating.

Description

Technical Field

[0001] The present invention relates to the technical field of functional anti-reflection coatings, in particular to a dual-coordinated sustained-release antibacterial anti-reflection coating and a preparation method thereof. Background Art

[0002] Anti-reflective coatings are thin dielectric coatings applied to optical surfaces. Inorganic materials are an important component of anti-reflective coatings, mainly including SiO2, MgF2, Al2O3, TiO2, and ZrO2. They have specific refractive indices. By precisely controlling the thickness and refractive index of the coating, light of different wavelengths can be made to destructively interfere on the coating surface, thereby reducing the intensity of the reflected light. However, when anti-reflective coatings are used in medical devices, the coating surface may become a potential habitat for microorganisms, which not only leads to reduced light transmission, but also may cause the spread of pathogenic microorganisms, thereby creating the risk of causing disease. Therefore, anti-reflective coatings need to have both high light transmittance and excellent antibacterial properties.

[0003] Achieving physical antibacterial properties by adjusting the nanostructure of antireflective coatings is an effective method. However, the manufacture of these nanostructures usually requires special materials, complex methods, and expensive equipment, which undoubtedly increases manufacturing costs. Introducing inorganic metal nanoparticles (such as Ag-NPs, Cu-NPs, and Zn-NPs) into the coating is a commonly used strategy. However, the presence of these nanoparticles increases the surface roughness of the coating, thereby increasing light scattering. The addition of non-granular organic antimicrobial agents to the coating can reduce the adverse effects of the introduction of additional substances on transmittance. Although antimicrobial agents such as quaternary ammonium salts, chlorophenols, and organic aldehydes do not form particles that block light transmission, long-term use can easily cause bacteria to develop drug resistance, thereby increasing the risk of transmission of pathogenic microorganisms.

[0004] Inorganic antimicrobial metals incorporated into coatings in the form of ions have become an ideal choice for antireflective coatings. Metal ions typically require carriers, such as zeolites and montmorillonite, to maintain their stability in the coating. However, the large size of these carriers in optical films creates significant obstacles to light propagation. This effect can be reduced if the metal ions are directly attached to the coating surface. Polydopamine (PDA), a commonly used bioadhesive, can precisely control the thickness of the coating at the nanoscale, minimizing its impact on light transmittance. Although current studies have shown that metal ions can undergo coordination reactions with polydopamine, firmly anchoring it to the PDA surface, the presence of trace amounts of water in the environment easily releases the antimicrobial metal ions from the coating surface, seriously affecting its service life. Therefore, developing a durable antimicrobial antireflective coating is a major challenge. Summary of the Invention

[0005] The present invention aims to solve at least one of the technical problems existing in the related art. To this end, the first object of the present invention is to provide a dual-coordinated sustained-release antibacterial antireflective coating; the second object of the present invention is to provide a preparation method.

[0006] In order to achieve the first purpose, the technical solution adopted by the present invention is:

[0007] A dual-coordinate sustained-release antibacterial and anti-reflective coating, comprising a dual-coordinate sustained-release antibacterial layer and a bottom layer, wherein the dual-coordinate sustained-release antibacterial layer is wrapped around the outer surface of the bottom layer;

[0008] The dual coordination sustained-release antibacterial layer includes an inner coordination layer, an antibacterial active layer and an outer coordination layer from the inside to the outside.

[0009] The inner coordination layer is wrapped around the outer surface of the bottom layer, and the inner coordination layer is composed of polydopamine;

[0010] The antibacterial active layer is wrapped around the outer surface of the inner coordination layer, and the components of the antibacterial active layer are metal ions;

[0011] The outer coordination layer is wrapped around the outer surface of the antibacterial active layer, and the component of the outer coordination layer is phytic acid;

[0012] The bottom layer is composed of inorganic nanoparticles.

[0013] Furthermore, the metal ions are copper ions and / or zinc ions.

[0014] Furthermore, the thickness of the inner coordination layer is 5 to 100 nm.

[0015] Furthermore, the content of metal ions in the antibacterial active layer is 1 to 50 μg / cm 2 .

[0016] Furthermore, the thickness of the outer coordination layer is 0.1 to 2 nm.

[0017] Furthermore, the inorganic nanoparticles are silicon dioxide nanoparticles and / or titanium dioxide nanoparticles.

[0018] Furthermore, the thickness of the bottom layer is 50 to 300 nm.

[0019] In order to achieve the second purpose, the technical solution adopted by the present invention is:

[0020] A preparation method for preparing any of the above-mentioned dual-coordinated sustained-release antibacterial and antireflective coatings comprises the following steps:

[0021] S100, preparing an inorganic nano sol-gel by a sol-gel method, immersing a substrate in the prepared inorganic nano sol-gel, pulling it up at a uniform speed, drying it, and sintering it at a high temperature to obtain a bottom layer;

[0022] S200, immersing the bottom layer in a dopamine solution for 1 to 24 hours, rinsing, and drying to obtain an inner coordination layer wrapped around the outer surface of the bottom layer;

[0023] S300, immersing the inner coordination layer in a metal salt solution for 0.5 to 2 hours, rinsing, and drying to obtain an antibacterial active layer wrapped around the outer surface of the inner coordination layer;

[0024] S400, immersing the antibacterial active layer in a phytic acid solution for 5 to 120 seconds, rinsing, and drying to obtain an outer coordination layer wrapped around the outer surface of the antibacterial active layer.

[0025] Furthermore, in step S300, the metal salt solution is one or more of copper sulfate, copper nitrate, copper chloride, copper acetate, zinc chloride, zinc nitrate, zinc sulfate and zinc acetate solution, and the concentration of the metal salt solution is 0.1-5 mg / ml.

[0026] Furthermore, in step S400, the concentration of the phytic acid solution is 0.05-10 mg / ml.

[0027] The above one or more technical solutions in the embodiments of the present invention have at least one of the following technical effects:

[0028] The dual-coordination sustained-release antimicrobial and antireflective coating provided by the present invention establishes a metal ion coordination platform on the surface of the inorganic nanocoating. The metal ions in the antimicrobial active layer react with polydopamine to form a chelate, which is firmly attached to the outer surface of the inner coordination layer. The metal ions in the antimicrobial active layer also react with phytic acid to form a complex, which forms a protective film that delays the release of the metal ions. This technical solution not only solves the problem of inorganic nanocoatings being easily contaminated by bacteria, but also delays the release of antimicrobial metal ions, thereby achieving a long-lasting antimicrobial and / or antibacterial effect.

[0029] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is a SEM photograph of the silicon dioxide nano-base layer provided in Example 1 of the present invention.

[0031] Figure 2 This is a SEM photograph of the polydopamine inner coordination layer provided in Example 1 of the present invention.

[0032] Figure 3 This is a nano-infrared spectrum (Nano-IR) photograph of the polydopamine inner coordination layer provided in Example 1 of the present invention.

[0033] Figure 4 This is an AFM comparison photograph of the silicon dioxide nano-base layer and the polydopamine inner coordination layer provided in Example 1 of the present invention.

[0034] Figure 5 This is a SEM photograph of the dual-coordinated sustained-release antibacterial and antireflective coating provided in Example 1 of the present invention.

[0035] Figure 6 This is an XPS photograph of the dual-coordinated sustained-release antibacterial and antireflective coating provided in Example 1 of the present invention. DETAILED DESCRIPTION

[0036] To make the purpose, technical solutions and advantages of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the present invention. Obviously, the embodiments described are part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention. The following embodiments are used to illustrate the present invention, but are not used to limit the scope of the present invention.

[0037] In the following examples, the experimental methods used are conventional methods unless otherwise specified, and the materials, reagents, etc. used are all available from commercial sources unless otherwise specified.

[0038] Example 1 Preparation of a dual-coordinated sustained-release antibacterial and antireflective coating on a glass plate.

[0039] 1. Preparation of silica nano-base layer.

[0040] Inorganic nanoparticles were prepared by the sol-gel method. 5 g of ethyl orthosilicate was added to 50 g of ethanol and stirred for 15 min. 0.12 g of ammonia water was added and stirred for 1 h. The mixture was allowed to stand for 7 days to obtain an inorganic nano sol-gel.

[0041] The cleaned glass plate was immersed in the inorganic nano-sol-gel and pulled up at a constant speed, dried, and sintered at 300°C for 1 hour to obtain a silica nano-base layer, which was wrapped around the outer surface of the glass plate. The silica nano-base layer was examined using a scanning electron microscope (SEM). Figure 1 As shown, the results show that the silica nanoparticles in the silica anti-reflective coating are evenly distributed and have an average particle size of about 17 nm.

[0042] 2. Preparation of polydopamine inner coordination layer.

[0043] 0.1g of dopamine and 0.12g of tris(hydroxymethyl)aminomethane) hydrochloric acid were added to 100g of deionized water and stirred for 1h to obtain a dopamine solution. The above-mentioned bottom layer was immersed in the dopamine solution for 6h, rinsed with deionized water 3 times, and placed in a 50℃ oven for 3h to obtain a polydopamine inner coordination layer, which was wrapped around the outer surface of the bottom layer. The polydopamine inner coordination layer was detected using SEM, as shown in FIG. Figure 2 As shown in the results, it was shown that the deposition of polydopamine did not change the surface morphology of silica nanoparticles. Figure 1 There is no significant change compared to the previous results. Nano-infrared microscopy was used to detect the silica nano-bottom layer and the polydopamine inner coordination layer. Figure 3 As shown, the results show that the inner coordination layer of deposited polydopamine is at 1528 cm -1 The stretching vibration peak of polydopamine (C=N) appears at the bottom of the silica nanoparticles, but no such peak is detected on the silica nanoparticles bottom layer, indicating that polydopamine is successfully deposited on the outer surface of the silica nanoparticles bottom layer. Atomic force microscopy was used to detect the coordination layer of the silica nanoparticles bottom layer and the polydopamine inner layer. Figure 4 As shown, the results show that the deposition of polydopamine on the silica surface reduces the surface roughness of the underlying layer from 5.54 nm to 3.66 nm. The reduction in the roughness of the underlying layer is beneficial to reducing light scattering and improving transmittance.

[0044] 3. Preparation of antibacterial active layer.

[0045] The inner coordination layer is immersed in a 0.5 mg / ml copper acetate solution for 1 hour, rinsed, and dried to obtain an antibacterial active layer, which is wrapped around the outer surface of the inner coordination layer.

[0046] 4. Preparation of outer coordination layer.

[0047] The antibacterial active layer prepared above was immersed in a 0.1 mg / ml phytic acid solution for 10 seconds, rinsed with deionized water three times, and then placed in a 40°C oven for 24 hours to obtain an outer coordination layer, which was wrapped around the outer surface of the antibacterial active layer.

[0048] The dual-coordination sustained-release antibacterial anti-reflective coating on the glass plate is composed of a silica nano-bottom layer, a polydopamine inner coordination layer, an antibacterial active layer and an outer coordination layer. The dual-coordination sustained-release antibacterial anti-reflective coating was tested using SEM, such as Figure 5 The results show that the sequential coordination of copper ions and phytic acid does not affect the surface morphology of the coating. The X-ray photoelectron spectroscopy (XPS) test results of the double-coordinated sustained-release antibacterial antireflective coating are as follows: Figure 6As shown in the figure, the results show that 8 characteristic peaks of elements were detected, namely Si2p, P2p, Si2s, C1, N1s, O1s, Cu2p3 / 2 and Cu2p1 / 2.

[0049] Example 2

[0050] 1. Preparation of silica nano-base layer.

[0051] Inorganic nanoparticles were prepared by the sol-gel method. 3 g of ethyl orthosilicate was added to 45 g of ethanol and stirred for 15 min. 0.12 g of ammonia water was added and stirred for 1 h. The mixture was allowed to stand for 7 days to obtain an inorganic nano sol-gel.

[0052] The cleaned glass plate was immersed in the above-mentioned inorganic nano sol-gel and pulled up at a uniform speed, dried, and sintered at a high temperature of 300°C for 1 hour to obtain a silica nano bottom layer, which was wrapped around the outer surface of the glass plate.

[0053] 2. Preparation of polydopamine inner coordination layer.

[0054] 0.1g of dopamine and 0.12g of tris(hydroxymethyl)aminomethane hydrochloride) were added to 100g of deionized water and stirred for 1 hour to obtain a dopamine solution. The substrate was immersed in the dopamine solution for 6 hours, rinsed with deionized water three times, and then placed in a 50°C oven for 3 hours to obtain a polydopamine inner coordination layer, which was wrapped around the outer surface of the substrate.

[0055] 3. Preparation of antibacterial active layer.

[0056] The inner coordination layer was immersed in a 0.5 mg / ml zinc acetate solution for 1 hour, rinsed, and dried to obtain an antibacterial active layer, which was wrapped around the outer surface of the inner coordination layer.

[0057] 4. Preparation of outer coordination layer.

[0058] The antibacterial active layer prepared above was immersed in a 0.5 mg / ml phytic acid solution for 100 seconds, rinsed with deionized water three times, and then placed in a 40°C oven for 24 hours to obtain an outer coordination layer. The outer coordination layer was wrapped around the outer surface of the antibacterial active layer to obtain a dual-coordination sustained-release antibacterial antireflective coating.

[0059] Example 3

[0060] 1. Preparation of silica nano-base layer.

[0061] Inorganic nanoparticles were prepared by the sol-gel method. 5 g of ethyl orthosilicate was added to 45 g of ethanol and stirred for 15 min. 0.18 g of ammonia water was added and stirred for 1 h. The mixture was allowed to stand for 7 days to obtain an inorganic nano sol-gel.

[0062] The cleaned glass plate was immersed in the above-mentioned inorganic nano sol-gel and pulled up at a uniform speed, dried, and sintered at a high temperature of 300°C for 1 hour to obtain a silica nano bottom layer, which was wrapped around the outer surface of the glass plate.

[0063] 2. Preparation of polydopamine inner coordination layer.

[0064] 0.1g of dopamine and 0.12g of tris(hydroxymethyl)aminomethane hydrochloride) were added to 100g of deionized water and stirred for 1 hour to obtain a dopamine solution. The substrate was immersed in the dopamine solution for 6 hours, rinsed with deionized water three times, and then placed in a 50°C oven for 3 hours to obtain a polydopamine inner coordination layer, which was wrapped around the outer surface of the substrate.

[0065] 3. Preparation of antibacterial active layer.

[0066] The inner coordination layer was immersed in a 0.1 mg / ml copper acetate solution for 1 hour, rinsed, and dried to obtain an antibacterial active layer, which was wrapped around the outer surface of the inner coordination layer.

[0067] 4. Preparation of outer coordination layer.

[0068] The antibacterial active layer prepared above was immersed in a 0.1 mg / ml phytic acid solution for 10 seconds, rinsed with deionized water three times, and placed in a 40°C oven for 24 hours to obtain an outer coordination layer. The outer coordination layer was wrapped around the outer surface of the antibacterial active layer to obtain a dual-coordination sustained-release antibacterial antireflective coating.

[0069] Example 4

[0070] 1. Preparation of silica nano-base layer.

[0071] Inorganic nanoparticles were prepared by the sol-gel method. 4 g of ethyl orthosilicate was added to 40 g of ethanol and stirred for 15 min. 0.18 g of ammonia water was added and stirred for 1 h. The mixture was allowed to stand for 7 days to obtain an inorganic nano sol-gel.

[0072] The cleaned glass plate was immersed in the above-mentioned inorganic nano sol-gel and pulled up at a uniform speed, dried, and sintered at a high temperature of 300°C for 1 hour to obtain a silica nano bottom layer, which was wrapped around the outer surface of the glass plate.

[0073] 2. Preparation of polydopamine inner coordination layer.

[0074] 0.1g of dopamine and 0.12g of tris(hydroxymethyl)aminomethane hydrochloride) were added to 100g of deionized water and stirred for 1 hour to obtain a dopamine solution. The substrate was immersed in the dopamine solution for 6 hours, rinsed with deionized water three times, and then placed in a 50°C oven for 3 hours to obtain a polydopamine inner coordination layer, which was wrapped around the outer surface of the substrate.

[0075] 3. Preparation of antibacterial active layer.

[0076] The inner coordination layer is immersed in a 3 mg / ml copper acetate solution for 1 hour, rinsed, and dried to obtain an antibacterial active layer, which is wrapped around the outer surface of the inner coordination layer.

[0077] 4. Preparation of outer coordination layer.

[0078] The antibacterial active layer prepared above was immersed in a 5 mg / ml phytic acid solution for 10 seconds, rinsed with deionized water three times, and then placed in a 40°C oven for 24 hours to obtain an outer coordination layer. The outer coordination layer was wrapped around the outer surface of the antibacterial active layer to obtain a dual-coordination sustained-release antibacterial antireflective coating.

[0079] Example 5

[0080] 1. Preparation of silica nano-base layer.

[0081] Inorganic nanoparticles were prepared by the sol-gel method. 5 g of ethyl orthosilicate was added to 45 g of ethanol and stirred for 15 min. 0.18 g of ammonia water was added and stirred for 1 h. The mixture was allowed to stand for 7 days to obtain an inorganic nano sol-gel.

[0082] The cleaned glass plate was immersed in the above-mentioned inorganic nano sol-gel and pulled up at a uniform speed, dried, and sintered at a high temperature of 300°C for 1 hour to obtain a silica nano bottom layer, which was wrapped around the outer surface of the glass plate.

[0083] 2. Preparation of polydopamine inner coordination layer.

[0084] 0.1g of dopamine and 0.12g of tris(hydroxymethyl)aminomethane hydrochloride) were added to 100g of deionized water and stirred for 1 hour to obtain a dopamine solution. The substrate was immersed in the dopamine solution for 6 hours, rinsed with deionized water three times, and then placed in a 50°C oven for 3 hours to obtain a polydopamine inner coordination layer, which was wrapped around the outer surface of the substrate.

[0085] 3. Preparation of antibacterial active layer.

[0086] The inner coordination layer is immersed in a 1 mg / ml copper acetate solution for 1 hour, rinsed, and dried to obtain an antibacterial active layer, which is wrapped around the outer surface of the inner coordination layer.

[0087] 4. Preparation of outer coordination layer.

[0088] The antibacterial active layer prepared above was immersed in a 0.1 mg / ml phytic acid solution for 30 seconds, rinsed with deionized water three times, and then placed in a 40°C oven for 24 hours to obtain an outer coordination layer. The outer coordination layer was wrapped around the outer surface of the antibacterial active layer to obtain a dual-coordination sustained-release antibacterial antireflective coating.

[0089] Comparative Example 1

[0090] 1. Preparation of silica nano-base layer.

[0091] Inorganic nanoparticles were prepared by the sol-gel method. 5 g of ethyl orthosilicate was added to 50 g of ethanol and stirred for 15 min. 0.12 g of ammonia water was added and stirred for 1 h. The mixture was allowed to stand for 7 days to obtain an inorganic nano sol-gel.

[0092] The cleaned glass plate was immersed in the above-mentioned inorganic nano sol-gel and pulled up at a uniform speed, dried, and sintered at a high temperature of 300°C for 1 hour to obtain a silica nano bottom layer, which was wrapped around the outer surface of the glass plate.

[0093] 2. Preparation of polydopamine inner coordination layer.

[0094] 0.1g of dopamine and 0.12g of tris(hydroxymethyl)aminomethane hydrochloride) were added to 100g of deionized water and stirred for 1 hour to obtain a dopamine solution. The substrate was immersed in the dopamine solution for 6 hours, rinsed with deionized water three times, and then placed in a 50°C oven for 3 hours to obtain a polydopamine inner coordination layer, which was wrapped around the outer surface of the substrate.

[0095] 3. Preparation of antibacterial active layer.

[0096] The above-mentioned inner coordination layer was immersed in a 0.5 mg / ml copper acetate solution for 1 hour, rinsed and dried, rinsed with deionized water three times, and placed in a 40°C oven for 24 hours to obtain an antibacterial active layer. The antibacterial active layer was wrapped around the outer surface of the inner coordination layer, thereby obtaining a monocoordinated antibacterial antireflective coating.

[0097] The dual-coordinate sustained-release antibacterial antireflective coating and the single-coordinate antibacterial antireflective coating prepared above were tested according to the standard coating antibacterial test. The test results are shown in Table 1.

[0098] Table 1 Results of light transmittance, antibacterial rate and antibacterial durability of Examples and Comparative Examples

[0099]

[0100] The dual-coordinate sustained-release antimicrobial antireflective coatings provided in Examples 1 to 5 have a bottom layer composed of a silica nanoparticle base layer and an average light transmittance greater than 96%. They exhibit antibacterial rates exceeding 99.99% against Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa. After immersion in water for 12 days, the dual-coordinate sustained-release antimicrobial antireflective coatings exhibited an antibacterial rate exceeding 80%. The single-coordinate antimicrobial antireflective coating provided in Comparative Example 1 has a bottom layer composed of a silica nanoparticle base layer and an average light transmittance greater than 96%. They exhibited an antibacterial rate exceeding 99.99% against Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa. However, the single-coordinate antimicrobial antireflective coating exhibited an antibacterial rate of 0% after immersion in water for 12 days. These results demonstrate that the dual-coordinate sustained-release antimicrobial antireflective coating provided by the present invention can enhance the long-term antimicrobial efficacy of the coating compared to the single-coordinate antimicrobial antireflective coating.

[0101] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A dual-coordinated sustained-release antibacterial antireflective coating, characterized in that: It comprises a dual coordination sustained-release antibacterial layer and a bottom layer, wherein the dual coordination sustained-release antibacterial layer is wrapped around the outer surface of the bottom layer; The dual coordination sustained-release antibacterial layer includes an inner coordination layer, an antibacterial active layer and an outer coordination layer from the inside to the outside. The inner coordination layer is wrapped around the outer surface of the bottom layer, and the inner coordination layer is composed of polydopamine; The antibacterial active layer is wrapped around the outer surface of the inner coordination layer, and the components of the antibacterial active layer include copper ions and / or zinc ions; The outer coordination layer is wrapped around the outer surface of the antibacterial active layer, and the component of the outer coordination layer is phytic acid; The bottom layer is composed of inorganic nanoparticles, which are silicon dioxide nanoparticles.

2. The dual-coordinated sustained-release antibacterial antireflective coating according to claim 1, characterized in that: The thickness of the inner coordination layer is 5 to 100 nm.

3. The dual-coordinated sustained-release antibacterial antireflective coating according to claim 1, characterized in that: The content of metal ions in the antibacterial active layer is 1 to 50 μg / cm 2 .

4. The dual-coordinated sustained-release antibacterial antireflective coating according to claim 1, wherein: The thickness of the outer coordination layer is 0.1-2 nm.

5. The dual-coordinated sustained-release antibacterial antireflective coating according to claim 1, characterized in that: The thickness of the bottom layer is 50 to 300 nm.

6. A preparation method, characterized in that: The method for preparing the dual-coordinated sustained-release antibacterial antireflective coating according to any one of claims 1 to 5 comprises the following steps: S100, preparing an inorganic nano sol-gel by a sol-gel method, immersing a substrate in the prepared inorganic nano sol-gel, pulling it up at a uniform speed, drying it, and sintering it at a high temperature to obtain a bottom layer; S200, immersing the bottom layer in a dopamine solution for 1 to 24 hours, rinsing, and drying to obtain an inner coordination layer wrapped around the outer surface of the bottom layer; S300, immersing the inner coordination layer in a metal salt solution for 0.5 to 2 hours, rinsing, and drying to obtain an antibacterial active layer wrapped around the outer surface of the inner coordination layer; S400, immersing the antibacterial active layer in a phytic acid solution for 5 to 120 seconds, rinsing, and drying to obtain an outer coordination layer wrapped around the outer surface of the antibacterial active layer.

7. The preparation method according to claim 6, wherein In step S300, the metal salt solution is one or more of copper sulfate, copper nitrate, copper chloride, copper acetate, zinc chloride, zinc nitrate, zinc sulfate and zinc acetate solutions, and the concentration of the metal salt solution is 0.1-5 mg / ml.

8. The preparation method according to claim 6, wherein In step S400, the concentration of the phytic acid solution is 0.05-10 mg / ml.

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