Deep eutectic eutectoid gel coating with antibacterial, anti-adhesion and anti-demineralization functions as well as preparation method and application of deep eutectic eutectoid gel coating

Abstract

The invention relates to the technical field of medical materials, and discloses a deep eutectic eutectoid gel coating with antibacterial, anti-adhesion and anti-demineralization functions as well as a preparation method and application of the deep eutectic eutectoid gel coating. The preparation method comprises the following steps: preparing a deep eutectic solvent by mixing SBMA and glycerol or glycerol and gallic acid; the preparation method comprises the following steps: adding a cross-linking agent ethylene glycol dimethacrylate and an initiator into a deep eutectic solvent, uniformly mixing, coating on a PETG substrate, and curing under the action of the initiator to form a continuous and compact deep eutectic eutectoid gel coating. A dense hydrogen bond network is constructed through a deep eutectic system formed by SBMA and glycerin, the hydrophilicity and lubricity of the coating are remarkably improved, adhesion of bacteria and protein in the oral cavity can be effectively reduced, cleanliness of the surface of the appliance is kept, a feasible and efficient technical path is provided for long-term biological functionalization of the invisible appliance, and the application prospect is wide. Meanwhile, the coating can be extensively applied to the fields of other oral medical instruments and biological functional coatings.

Description

Technical Field

[0001] This invention relates to the field of medical materials technology, specifically to a deep eutectic eutectoid gel coating with antibacterial, anti-adhesion and anti-demineralization functions, its preparation method and application. Background Technology

[0002] With the widespread application of invisible orthodontic technology, invisible aligners (such as aligners made of transparent polymer materials like PETG (polyethylene terephthalate-1,4-cyclohexanediol ester)) have gradually replaced some traditional fixed orthodontic methods due to their aesthetic appeal and removability. However, during long-term wear, the closed microenvironment formed between the invisible aligner and the tooth surface restricts saliva flow, making it easier for food debris and plaque to accumulate. This leads to a decrease in local pH, which accelerates the dissolution of hydroxyapatite crystals in tooth enamel and induces tooth demineralization.

[0003] Furthermore, the repeated friction between the wearing and removal of invisible aligners and the tooth surface increases the risk of mechanical damage and demineralization of the enamel. Over time, localized demineralization can manifest as leukoplakia, which not only affects the appearance of the teeth but may also develop into tooth decay.

[0004] Most existing invisible aligners only provide mechanical correction and lack effective antibacterial and demineralization protection mechanisms, making it difficult to maintain oral microenvironment stability during long-term treatment. Although some studies have attempted to endow them with certain biofunctionality through drug impregnation, surface coating, or polymer modification, problems such as uneven drug release, poor material adhesion, insufficient biocompatibility, and complex manufacturing processes limit their clinical application.

[0005] Therefore, there is an urgent need to develop a functional coating material that simultaneously possesses antibacterial, anti-adhesion, and anti-demineralization functions, capable of forming a stable, durable, and controllably released protective layer on the surface of invisible aligners to prevent demineralization and plaque formation caused by oral microenvironment imbalance, thereby improving dental health and material comfort during orthodontic treatment. Summary of the Invention

[0006] To address the shortcomings of current invisible orthodontic devices in terms of antibacterial properties, anti-adhesion properties, and anti-demineralization properties, this invention provides a deep eutectic eutectoid gel coating with antibacterial, anti-adhesion, and anti-demineralization functions, along with its preparation method and application.

[0007] To achieve the above objectives, on the one hand, the present invention provides a method for preparing a deep eutectic eutectoid gel coating with antibacterial, anti-adhesion, and anti-demineralization functions, which includes the following steps: S1. Using sulfobetaine methacrylate as a hydrogen bond acceptor and glycerol or glycerol and gallic acid as hydrogen bond donors, the hydrogen bond acceptor and hydrogen bond donors are mixed and stirred under heating conditions to form a homogeneous and transparent deep eutectic solvent. S2. Add crosslinking agent ethylene glycol dimethacrylate and initiator to the deep eutectic solvent, mix evenly, and then coat it onto the PETG substrate. Under the action of the initiator, it is cured to form a continuous and dense deep eutectic eutectoid gel coating with antibacterial, anti-adhesion and anti-demineralization functions on the surface of the PETG substrate.

[0008] As a further preferred embodiment of the present invention, the molar ratio of the hydrogen bond acceptor to the hydrogen bond donor is 1:3~5; and / or, the gallic acid accounts for 0~10% of the molar amount of glycerol.

[0009] As a further preferred embodiment of the present invention, the molar ratio of the hydrogen bond acceptor to the hydrogen bond donor is 1:4, and the gallic acid accounts for 4 to 6% of the molar amount of glycerol.

[0010] As a further preferred technical solution of the present invention, in step S1, when gallic acid is not present, the heating temperature for forming the deep eutectic solvent is 30~45 ℃; when gallic acid is present, the heating temperature for forming the deep eutectic solvent is 50~60 ℃; wherein the stirring time is 10~100 minutes.

[0011] As a further preferred embodiment of the present invention, the amount of the crosslinking agent is 0.5 to 5% of the molar amount of the hydrogen bond acceptor; and / or, the concentration of the initiator is 0.1 to 1 wt.

[0012] As a further preferred technical solution of the present invention, the initiator is 2-methyl-1-phenyl-1-propanone (also known as photoinitiator 1173), and ultraviolet light with a wavelength of 365 nm and a power of 10~20 mW / cm² is used for curing.

[0013] As a further preferred embodiment of the present invention, the PETG substrate undergoes surface modification treatment before coating, and the surface modification method is as follows: 1) Place the PETG substrate in a plasma cleaner and perform plasma surface activation treatment at a power of 30~50 W for 1~5 min to introduce surface hydroxyl groups and active sites. 2) Immerse the plasma-treated PETG substrate in a mixed solution of ethanol and water of 3-(isobutyrooxy)propyltrimethoxysilane (IBMA-Silane) and react at a constant temperature of 40~60 °C for 1~5 h to form a dense organosilicon layer on the surface of the silane coupling agent. After the reaction is completed, wash and dry.

[0014] As a further preferred embodiment of the present invention, the PETG substrate is an invisible brace or a sheet used to prepare an invisible brace.

[0015] According to a second aspect of the present invention, the present invention also provides a deep eutectic eutectoid gel coating, which is prepared by the above-described preparation method.

[0016] According to a third aspect of the present invention, the present invention also provides the application of a deep eutectic eutectoid gel coating in the surface modification of invisible orthodontic devices, for achieving multifunctional synergistic protection with antibacterial, anti-protein adhesion and anti-demineralization properties.

[0017] Compared with the prior art, the present invention can achieve the following beneficial effects: (1) The present invention constructs a dense hydrogen bond network through a deep eutectic system formed by SBMA and glycerol, which significantly improves the hydrophilicity and lubricity of the coating, effectively reduces the adhesion of bacteria and proteins in the oral cavity, and keeps the surface of the orthodontic appliance clean.

[0018] (2) The present invention can achieve a slow-release function in an aqueous environment by introducing gallic acid (GA) to form a ternary deep eutectic structure, giving the coating a lasting antibacterial property and the ability to promote remineralization, which helps to prevent enamel demineralization and white spot formation.

[0019] (3) The preparation process of this invention is mild and simple, requiring no organic solvents or high temperature conditions. It is suitable for the modification of polymer substrate surfaces such as invisible orthodontics, and has good processability and potential for large-scale application.

[0020] Therefore, the deep eutectic eutectoid gel coating material provided by this invention has antibacterial, anti-adhesion and anti-demineralization properties, providing a feasible and efficient technical path for the long-term biofunctionalization of invisible orthodontic appliances, and can also be extended to other oral medical devices and biofunctional coating fields. Attached Figure Description

[0021] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0022] Figure 1 Cross-sectional SEM images of pure PETG, modified PETG, SBMA-glycerol coating, and SBMA-glycerol-GA coating.

[0023] Figure 2 Surface SEM images of pure PETG, modified PETG, SBMA-glycerol coating, and SBMA-glycerol-GA coating.

[0024] Figure 3 EDS elemental analysis results for PETG, modified PETG, SBMA-glycerol coating, and SBMA-glycerol-GA coating.

[0025] Figure 4 XPS analysis images of pure PETG, modified PETG, SBMA-glycerol coating, and SBMA-glycerol-GA coating.

[0026] Figure 5 FTIR spectra of pure PETG, modified PETG, SBMA-glycerol coating, and SBMA-glycerol-GA coating.

[0027] Figure 6 The GA release curve is for the SBMA-glycerol-GA coating.

[0028] Figure 7 Tensile property test curves for pure PETG, SBMA-glycerol coating, and SBMA-glycerol-GA coating.

[0029] Figure 8 The results of antibacterial coating against Escherichia coli and Staphylococcus aureus are shown in the following groups: a: control group; b: SBMA-glycerol coating group; c: SBMA-glycerol-GA coating group; d: control group; e: SBMA-glycerol coating group; f: SBMA-glycerol-GA coating group.

[0030] Figure 9 The images show protein adhesion fluorescence patterns, where a: control group; b: SBMA-glycerol coating group; c: SBMA-glycerol-GA coating group; d: control group; e: SBMA-glycerol coating group; f: SBMA-glycerol-GA coating group.

[0031] Figure 10 SEM images of the initial demineralized dental slides and the slides after being coated with pure PETG, SBMA-glycerol, and SBMA-glycerol-GA for 7 days.

[0032] Figure 11 The results show the biocompatibility of pure PETG, SBMA-glycerol coating, and SBMA-glycerol-GA coating with human gingival epithelial cells (HOK).

[0033] Figure 12 Peel tests were performed on SBMA-glycerol coatings and SBMA-glycerol-GA coatings.

[0034] The objectives, features, and advantages of this invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0035] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0036] Unless otherwise defined, the technical terms used in the following embodiments have the same meanings as commonly understood by those skilled in the art to which this invention pertains. Unless otherwise specified, the experimental reagents used in the following embodiments are conventional biochemical reagents; and the experimental methods described are conventional methods.

[0037] The raw materials used in the examples, SBMA (sulfobetaine methacrylate), glycerol, gallic acid (GA), photoinitiator Irgacure 2959 (1173) and crosslinking agent ethylene glycol dimethacrylate (EMMA), were all commercially available analytical grade reagents and were used directly without further purification.

[0038] Example 1: Preparation of SBMA-glycerol co-deposition gel coating This embodiment provides a method for preparing a DES co-deposition gel coating formed by SBMA and glycerol, the steps of which are as follows: (1) Surface modification treatment of PETG substrate: Pure PETG sheet (approximately 1 cm × 1 cm in size) was placed in a plasma cleaner and subjected to plasma surface activation treatment at 40 W for 2 min to introduce surface hydroxyl groups and active sites. The plasma-treated PETG sheet was immediately immersed in an ethanol-water (volume ratio 9:1) solution of 3-(isobutenoyloxy)propyltrimethoxysilane (IBMA-Silane) and reacted at 60°C for 3 h to form a dense organosilicon layer on the PETG surface with the silane coupling agent, thereby introducing active groups that can copolymerize with the double bonds in the subsequent coating. After the reaction, the sample was rinsed with ethanol and deionized water in sequence to remove unreacted coupling agent and dried in a 50°C oven for later use to obtain modified PETG sheet for subsequent coating reaction.

[0039] (2) Formation of DES: Weigh 558.7 mg (4 mmol) of SBMA and 736.72 mg (16 mmol) of glycerol and add them to the reaction flask. Stir for 20 min in an oil bath at 35 °C. The system gradually changes from turbid to transparent, and a homogeneous deep eutectic solution (DES) is obtained.

[0040] (3) Addition of photocurable components: In the above transparent DES system, add photoinitiator 1173 (concentration of 1 wt% of the total mass of the system) and crosslinking agent (EMMA, amount of 1% of the molar amount of SBMA), and stir thoroughly to form a reaction precursor solution.

[0041] (4) Coating and UV curing: The modified PETG sheet is placed in a clean environment, and the reaction precursor liquid is drop-coated onto its surface and allowed to spread naturally into a film. Then, it is placed under a UV lamp (365 nm, 10 mW / cm²) for 10 min to complete the photocrosslinking and curing, forming a dense SBMA-glycerol coating on the modified PETG sheet.

[0042] Example 2: Preparation of SBMA-glycerol-GA co-deposition gel coating This embodiment provides a method for preparing a ternary DES co-deposition gel coating by introducing gallic acid (GA) into an SBMA and glycerol system, the steps of which are as follows: (1) Surface modification treatment of PETG substrate: Pure PETG sheet with a size of about 1 cm × 1 cm was placed in a plasma cleaner and subjected to plasma surface activation treatment at a power of 40 W for 5 min to introduce surface hydroxyl groups and active sites. The plasma-treated PETG sheet was immediately immersed in an ethanol-water (volume ratio 9:1) solution of 3-(isobutenoyloxy)propyltrimethoxysilane (IBMA-Silane) and reacted at a constant temperature of 60°C for 3 h to form a dense organosilicon layer on the PETG surface by the silane coupling agent, thereby introducing active groups that can copolymerize with the double bonds in the subsequent coating. After the reaction, the sample was rinsed with ethanol and deionized water in sequence to remove unreacted coupling agent and dried in a 50°C oven for later use to obtain modified PETG sheet for subsequent coating reaction.

[0043] (1) Formation of DES: Weigh 558.7 mg (4 mmol) of SBMA, 699.884 mg (15.2 mmol) of glycerol and 68.048 mg (0.8 mmol) of GA, place them in a reaction flask, and stir magnetically for 20 min in an oil bath at 65℃. The system gradually transforms into a transparent and homogeneous liquid, forming a ternary deep eutectic solution of SBMA-glycerol-GA (DES).

[0044] (2) Addition of photocurable components: In the above transparent DES system, add photoinitiator 1173 (concentration of 1 wt% of the total mass of the system) and crosslinking agent (EMMA, amount of 1% of the molar amount of SBMA), and stir thoroughly to form a reaction precursor solution.

[0045] (4) Coating and UV curing: The modified PETG sheet was placed in a clean environment, and the reaction precursor liquid was dropped onto its surface (the amount of drop was the same as in Example 1), allowing it to spread naturally into a film. Then, it was placed under a UV lamp (365 nm, 10 mW / cm²) for 10 min to complete the photocrosslinking and curing, forming a dense SBMA-glycerol-GA ternary co-deposition gel coating on the modified PETG sheet.

[0046] The pure PETG sheets (denoted as PETG) from Examples 1 and 2, as well as the prepared modified PETG sheets (denoted as Si-PETG), SBMA-glycerol coatings (denoted as SBMA-G), and SBMA-glycerol-GA coatings (denoted as SBMA-G-GA), were used as test objects, and the following comparative tests were performed. The results are as follows. Figures 1-11 As shown.

[0047] 1) Structural characterization: The cross-sections of the pure PETG sheets from Examples 1 and 2, as well as the prepared modified PETG sheets, SBMA-glycerol coatings, and SBMA-glycerol-GA coatings, were scanned using a scanning electron microscope. The results are as follows: Figure 1 As shown, both the SBMA-glycerol coating and the SBMA-glycerol-GA coating formed a continuous, dense layer on the PETG surface, with a thickness of approximately 50 μm, indicating successful coating construction.

[0048] The surfaces of the pure PETG sheets from Examples 1 and 2, as well as the prepared modified PETG sheets, SBMA-glycerol coatings, and SBMA-glycerol-GA coatings, were scanned using a scanning electron microscope. The results are as follows: Figure 2 As shown, the introduction of the coating did not significantly change the macroscopic morphology of the PETG surface, which remained smooth and flat.

[0049] EDS elemental analysis was performed on the pure PETG sheets from Examples 1 and 2, as well as the prepared modified PETG sheets, SBMA-glycerol coating, and SBMA-glycerol-GA coating. The results are as follows: Figure 3 As shown, the N and S element signals are significantly enhanced with the introduction of the coating, indicating that the SBMA structure was successfully coated on the PETG surface; while the Si signal decreases, indicating that the original silane coupling layer was covered by the coating.

[0050] XPS analysis was performed on the pure PETG sheets from Examples 1 and 2, as well as the prepared modified PETG sheets, SBMA-glycerol coating, and SBMA-glycerol-GA coating. The results are as follows: Figure 4 As shown, obvious Si–O and Si–C peaks appear in the modified PETG material, proving the successful silane coupling. In both coating groups, these signals weaken, while N peaks and C–N and C=O enhancements appear, proving the successful introduction of SBMA and GA, forming a stable eutectoid network. That is, with the addition of the coating, the Si-O and Si-C bonds are weakened and covered, and due to the quaternary ammonium salt and some hydrogen bonding in SBMA, their content increases with the addition of the coating, proving the successful synthesis of the coating.

[0051] The Fourier transform infrared spectra of the pure PETG sheets from Examples 1 and 2, as well as the prepared modified PETG sheets, SBMA-glycerol coating, and SBMA-glycerol-GA coating, were obtained, such as... Figure 5 As shown, the modified PETG material exhibits a C=O characteristic peak at 1635 cm⁻¹; the SBMA characteristic peak of C–N stretching vibration appears at 953 cm⁻¹; and the GA benzene ring C–H out-of-plane bending vibration peak appears at approximately 800 cm⁻¹, all of which verify the successful integration of the coating's chemical composition.

[0052] 2) Functional performance testing: Figure 6 The GA release curve for the SBMA-glycerol-GA coating shows that the GA release is essentially complete within 48 hours, exhibiting typical water-responsive and controllable release characteristics. The specific test method is as follows: PETG sheets containing the SBMA-glycerol-GA coating (Example 2) were immersed in an aqueous solution. Immersion solutions were collected and replenished at 3, 6, 9, 12, 24, and 48 hours. The obtained solutions were compared with the standard GA concentration. The concentration of GA in the immersion solutions was measured using ultraviolet light to plot the GA release curve. The curve shows that the SBMA-glycerol-GA coating exhibits water-responsive GA release characteristics, and the complete release within 48 hours demonstrates a certain degree of sustained-release. This is beneficial for eliminating surrounding bacteria during invisible orthodontic treatment, thus protecting teeth from damage.

[0053] Figure 7 The tensile property test curves for each group of PETG samples are shown. The results indicate that the tensile strength and elongation at break of the SBMA-glycerol and SBMA-glycerol-GA coated samples are basically consistent with the original PETG, indicating that the coating did not weaken the mechanical properties of the substrate. The specific test method was as follows: pure PETG sheets, as well as PETG sheets with SBMA-glycerol coating and SBMA-glycerol-GA coating, were cut into dumbbell shapes using a die and subjected to tensile testing using a tensile testing machine. Figure 7 As can be seen from point a, the coating does not have a significant impact on PETG; Figure 7 Figure b is a bar chart of the tensile force of PETG sheet, which shows that the coating has no effect on its tensile force. Figure 7 In the figure, 'c' represents the tensile modulus, and it can also be seen that the coating does not have a significant impact on its tensile modulus.

[0054] Figure 8 This is the result of antibacterial plating against Escherichia coli and Staphylococcus aureus. The procedure involved plating coated and uncoated PETG sheets with 10... 6After co-culturing with CFU / mL bacterial suspension for 4 hours, the samples were plated for further incubation. Results showed that the SBMA-glycerol-GA group achieved a bactericidal rate of approximately 98%, significantly superior to the two-component coating. The specific testing method involved cutting pure PETG sheets, as well as PETG sheets with SBMA-glycerol and SBMA-glycerol-GA coatings, into 1*1cm squares. These squares were then co-cultured with Staphylococcus aureus and Escherichia coli at a bacterial concentration of 10^6 for 4 hours. 10 μL of the co-culture solution was then plated to observe the bactericidal ability of the coatings. The results clearly demonstrate that the SBMA-glycerol-GA group exhibited a strong bactericidal ability exceeding 98%, showing the best performance.

[0055] Figure 9 The results show the fluorescence of protein adhesion. FITC-labeled bovine serum albumin (BSA) and lysozyme were used as model proteins, co-cultured with the samples in PBS for 2 h, and then observed. The results showed strong fluorescence on the PETG surface, while the two coated samples showed extremely weak fluorescence, indicating that the coating significantly reduced protein adhesion. The specific testing method involved cross-linking bovine whey protein and lysozyme with fluorescent labels to form fluorescently labeled proteins. The fluorescently labeled protein solution was co-cultured with 1*1cm experimental PETG sheets for 1 hour. After incubation, the protein adhesion on the sheets was observed using a confocal microscope. Fluorescence was observed in the uncoated pure PETG material, indicating protein adhesion to the substrate. However, the two coated groups, namely the SBMA-glycerol coating and the SBMA-glycerol-GA coating, showed no obvious fluorescence, indicating that no significant protein adhesion occurred on the coated substrate.

[0056] Figure 10SEM images of the initial demineralized tooth slices and those coated with PETG, SBMA-glycerol, and SBMA-glycerol-GA for 7 days are shown. Results show that newly formed needle-like crystal structures appeared on the surface of the SBMA-glycerol-GA group, suggesting that GA promotes remineralization. The specific testing method was as follows: To investigate whether the coatings could remineralize demineralized enamel, bovine teeth were cut into 1*1cm slices and fixed in resin. The surface was lightly polished and etched with 35% phosphoric acid to remove all minerals and expose the columnar dentin structure. Experimental PETG sheets with gaps were fixed to the tooth surface and immersed in artificial saliva for 7 days, with daily saliva changes. This simulated the contact between the aligners and the teeth during invisible orthodontic treatment, providing a fluid-flowing environment. As can be seen, the dentin structure on the pure PETG sheet is similar to that of the original untreated dentin, and no new crystal forms appear. The group covered with PETG sheet with SBMA-glycerol coating also did not form any new minerals. However, the group covered with PETG sheet with SBMA-glycerol-GA coating showed obvious formation of new minerals. This is because GA has a certain effect of recruiting minerals and inducing remineralization.

[0057] Figure 11 The biocompatibility results for each group with human gingival epithelial cells (HOK) are presented. CCK-8 assay and live / dead staining results showed that neither the SBMA-glycerol nor the SBMA-glycerol-GA group affected cell proliferation and morphology, demonstrating good biocompatibility. The specific testing method involved co-culturing experimental PETG sheets with cell culture medium to obtain an extract. HOK cells were cultured using this extract, and cell proliferation was measured after 24 hours. CCK-8 analysis showed that the coated PETG sheets did not affect cell proliferation in either group. Live / dead staining also indicated that the coating had no effect on cell morphology. Morphological observation using staining showed that the coating did not significantly affect cell morphology.

[0058] The test method for Lap shear strength is illustrated as follows: Figure 12 As shown in Figure a, pure PETG sheets were cut to a size of 1*3cm, and a coating with an area of ​​1*1cm was applied between two layers of PETG sheets. The adhesion force of the coating was measured by stretching it up and down. Figure b shows the adhesion force and mechanical strength of the coating obtained from parallel samples of the SBMA-glycerol group and the SBMA-glycerol-GA group coatings. Figure 12 In the diagram, c represents the specific mechanical trend curve of the group closest to the average value in b. This demonstrates that the coatings obtained in Examples 1 and 2 both possess excellent adhesion properties.

[0059] In summary, compared with Example 2, the introduction of GA in Example 1 leads to a richer hydrogen bond network structure in the system, which not only enhances the intermolecular forces of the coating but also further improves its antibacterial properties and bioactivity, while maintaining good lubricity and transparency.

[0060] While specific embodiments of the present invention have been described above, those skilled in the art should understand that these are merely illustrative examples, and various changes or modifications can be made to these embodiments without departing from the principles and essence of the present invention. The scope of protection of the present invention is defined only by the appended claims.

Claims

1. A method for preparing a deep eutectic eutectoid gel coating with antibacterial, anti-adhesion, and anti-demineralization functions, characterized in that, Includes the following steps: S1. Using sulfobetaine methacrylate as a hydrogen bond acceptor and glycerol or glycerol and gallic acid as hydrogen bond donors, the hydrogen bond acceptor and hydrogen bond donors are mixed and stirred under heating conditions to form a homogeneous and transparent deep eutectic solvent. S2. Add crosslinking agent ethylene glycol dimethacrylate and initiator to the deep eutectic solvent, mix evenly, and then coat it onto the PETG substrate. Under the action of the initiator, it is cured to form a continuous and dense deep eutectic eutectoid gel coating with antibacterial, anti-adhesion and anti-demineralization functions on the surface of the PETG substrate.

2. The method for preparing a deep eutectic eutectoid gel coating with antibacterial, anti-adhesion, and anti-demineralization functions according to claim 1, characterized in that, The molar ratio of the hydrogen bond acceptor to the hydrogen bond donor is 1:3 to 5; and / or, the gallic acid accounts for 0 to 10% of the molar amount of glycerol.

3. The method for preparing a deep eutectic eutectoid gel coating with antibacterial, anti-adhesion, and anti-demineralization functions according to claim 2, characterized in that, The molar ratio of the hydrogen bond acceptor to the hydrogen bond donor is 1:4, and the gallic acid accounts for 4-6% of the molar amount of glycerol.

4. The method for preparing a deep eutectic eutectoid gel coating with antibacterial, anti-adhesion, and anti-demineralization functions according to claim 1, characterized in that, When gallic acid is absent, the heating temperature for forming a deep eutectic solvent is 30~45 ℃; when gallic acid is present, the heating temperature for forming a deep eutectic solvent is 50~60 ℃.

5. The method for preparing a deep eutectic eutectoid gel coating with antibacterial, anti-adhesion, and anti-demineralization functions according to claim 1, characterized in that, The amount of the crosslinking agent is 0.5 to 5% of the molar amount of the hydrogen bond acceptor; and / or, the concentration of the initiator is 0.1 to 1 wt%.

6. The method for preparing a deep eutectic eutectoid gel coating with antibacterial, anti-adhesion, and anti-demineralization functions according to claim 1, characterized in that, The initiator is the photoinitiator Irgacure 2959, and the curing process uses ultraviolet light with a wavelength of 365 nm and a power of 10~20 mW / cm².

7. The method for preparing a deep eutectic eutectoid gel coating with antibacterial, anti-adhesion, and anti-demineralization functions according to claim 1, characterized in that, The PETG substrate underwent surface modification treatment before coating, and the surface modification method is as follows: 1) Place the PETG substrate in a plasma cleaner and perform plasma surface activation treatment at a power of 30~50 W for 1~5 min to introduce surface hydroxyl groups and active sites. 2) Immerse the plasma-treated PETG substrate in a mixed solution of ethanol and water of 3-(isobutyrooxy)propyltrimethoxysilane (IBMA-Silane) and react at a constant temperature of 40~60 °C for 1~5 h to form a dense organosilicon layer on the surface of the silane coupling agent. After the reaction is completed, wash and dry.

8. The method for preparing a deep eutectic eutectoid gel coating with antibacterial, anti-adhesion, and anti-demineralization functions according to any one of claims 1-7, characterized in that, The PETG substrate is a clear aligner or a sheet used to prepare a clear aligner.

9. A deep eutectic eutectoid gel coating, characterized in that, It is prepared by the preparation method according to any one of claims 1-8.

10. The application of the deep eutectic eutectoid gel coating of claim 9 in the surface modification of invisible orthodontic devices.

Images