Lightweight wear-resistant antibacterial medical coating and preparation method

Abstract

The present application provides a kind of light wear-resistant bacteriostatic medical coating, including titanium transition layer, and diamond-like carbon film layer in the surface of titanium transition layer, silver and copper are contained in the diamond-like carbon film layer;And the preparation method of light wear-resistant bacteriostatic medical coating, including S1: raw material preparation and pretreatment;S2: Ar ion etching;S3: Ti transition layer deposition;S4: Ag, Cu co-doped deposition;S5: cooling, breaking vacuum.This technical solution has broad-spectrum bacteriostatic effect, and high bacteriostatic rate, reaches high-efficiency sterilization under lower total metal content, reduces endoscope related cross infection problem;Meanwhile, the coating has strong chemical inertness, dense structure without pore, resists multiple disinfection methods, titanium transition layer and silver copper doped structure do not dissolve, do not fail, avoid the problem that traditional antibacterial coating rapidly degrades, fails, falls off after repeated disinfection, meanwhile, the corrosion of disinfection medium to internal metal matrix is isolated, the performance of instrument is stable.

Description

Technical Field

[0001] This invention relates to the field of medical coatings, and more particularly to a lightweight, wear-resistant, and antibacterial medical coating and its preparation method. Background Technology

[0002] Medical endoscopes, as core equipment for minimally invasive diagnosis and treatment, cannot be completely sterilized due to their precise structure, long and narrow lumen, and complex components. Furthermore, medical endoscopes undergo a harsh service environment involving repeated insertion and removal friction and cyclical disinfection with various types of sterilizing media, making them high-risk carriers of cross-infection. Most existing endoscope surface coatings are organic, focusing on lubrication and friction reduction. Therefore, after repeated friction and disinfection, the existing endoscope surface, including the coating, is prone to wear, substrate corrosion, and micro-gaps, creating blind spots for pathogens to hide and colonize, thus hindering infection control. Therefore, a medical coating that is both wear-resistant and antibacterial is needed. Summary of the Invention

[0003] To solve the above problems, the present invention adopts the following technical solution: A lightweight, wear-resistant, and antibacterial medical coating includes a titanium transition layer and a diamond-like carbon film layer located on the surface of the titanium transition layer, wherein the diamond-like carbon film layer contains silver and copper.

[0004] The titanium transition layer forms a metallurgical bonding interface on the surface of the workpiece substrate, while providing stress buffer and transition for the diamond-like carbon film, playing a role in interface strengthening. This facilitates the subsequent adhesion and formation of the diamond-like carbon film on its surface, and reduces problems such as peeling, cracking, and detachment of the diamond-like carbon film in complex areas such as curved surfaces, corners, and channel openings of the endoscope, thereby improving the service life of the endoscope.

[0005] The diamond-like carbon (DLC) film contains silver and copper elements. The synergistic use of silver and copper gives this coating a broad-spectrum antibacterial effect and a high antibacterial rate, achieving highly efficient sterilization with a lower total metal content, thus reducing the risk of cross-infection related to endoscopy. Simultaneously, the negative enthalpy of mixing of copper and titanium allows them to diffuse at the interface during deposition, forming intermetallic compounds such as CuTi and CuTi3. This interfacial reaction layer achieves chemical bonding (metallurgical bonding), significantly improving film adhesion and further preventing problems such as peeling, cracking, and detachment of the DLC film.

[0006] Furthermore, copper exhibits more stable magnetron sputtering characteristics and excellent compatibility with graphite C targets and titanium targets. The introduction of copper makes the plasma more stable during multi-target co-sputtering of graphite C targets and titanium targets, allowing for more precise control of the silver and copper doping ratio during the coating process. This reduces fluctuations in composition and performance during processing, thereby improving the precision of the prepared coating. At the same time, copper is a soft metal solid lubricant, forming a uniform and continuous copper-based transfer film at the mating interface during friction. Combined with the diamond-like carbon film layer, this further reduces the coefficient of friction and wear rate of the coating, avoiding fine scratches on the surface during friction and the fluctuation of the coefficient of friction of the DLC film under dry friction and fluid lubrication conditions.

[0007] This coating is chemically inert, has a dense and non-porous structure, and is resistant to various disinfection methods. Furthermore, the titanium transition layer and the silver-copper doped structure do not dissolve or fail, avoiding the problems of rapid degradation, failure, and peeling of traditional antibacterial coatings after repeated disinfection. At the same time, it isolates the disinfection medium from the corrosion of the substrate inside the coating, ensuring the stable performance of the instruments.

[0008] Furthermore, the titanium transition layer also includes a pure titanium underlayer and TiC. X The gradient middle layer, TiC-DLC top layer, and titanium transition layer have a total thickness of 0.05~0.2μm.

[0009] The thickness is set at 0.05~0.2μm to balance the adhesion guarantee and the precision requirements of the endoscope. The lower limit of 0.05μm ensures that the transition layer forms a continuous, dense, and pinhole-free thin film structure, which can completely cover the surface of the endoscope substrate and effectively isolate the substrate from plasma damage during subsequent deposition. At the same time, it provides a uniform adhesion substrate for the surface diamond-like carbon film, avoiding poor adhesion and local detachment caused by an excessively thin transition layer. The upper limit of 1.0μm avoids excessive internal stress caused by an excessively thick transition layer, preventing the transition layer itself from warping and cracking, and does not change the precision dimensions and fitting clearance of the endoscope components, adapting to the miniaturized and high-precision structural characteristics of the endoscope.

[0010] Furthermore, the thickness of the pure titanium substrate is 0.02~0.05μm, and the TiC... X The thickness of the gradient middle layer is 0.05~0.1μm, and the thickness of the TiC-DLC top layer is 0.03~0.5μm; and TiC X The gradient middle layer transitions linearly from a Ti / C atomic ratio of 9:1 to 1:9 near the pure titanium bottom layer and near the TiC-DLC top layer; the TiC X The gradient middle layer and the TiC-DLC top layer are in-situ doped with 0.5-1 at.% Ag and Cu.

[0011] The three-layer transition structure, while ensuring the original enhanced interface bonding effect, TiC XThe gradient middle layer and TiC-DLC top layer have high hardness, which is close to that of diamond-like carbon film. They are also doped with a certain amount of Ag and Cu, which avoids the problem that the pure titanium layer has no antibacterial ability and is easily worn down by the relatively soft pure titanium layer after the diamond-like carbon film wears or develops scratches or cracks.

[0012] Furthermore, the diamond-like carbon film is an Ag- or Cu-doped diamond-like carbon film with a thickness of 0.25~3.0 μm.

[0013] With a thickness of not less than 0.25μm, the diamond-like carbon film is guaranteed to form a continuous, dense, pinhole-free, and uncoated uniform film layer, effectively blocking the corrosion of the base metal by body fluids, disinfectants, tissue fluids, etc., and preventing the leaching of the base or coating components, thus improving the safety of endoscope use.

[0014] With a thickness not exceeding 3.0μm, it avoids problems such as excessive internal stress, increased brittleness, easy cracking, and easy warping and peeling caused by excessively thick film layers. It is especially suitable for complex curved surfaces, corners, edges and other locations where stress is easily concentrated, ensuring that the coating layer does not fail after long-term repeated use.

[0015] Furthermore, the silver content in the diamond-like carbon film is 3.0~5.0 at.%, and the copper content is 1.5~3.0 at.%.

[0016] The silver and copper content is within the aforementioned low-doping range, which will not excessively damage the sp(s) content of the diamond-like carbon film. 3 The bonded structure can retain the core advantages of DLC itself, such as high hardness, high wear resistance and low friction coefficient, while introducing antibacterial function. It avoids problems such as film softening, hardness reduction and insufficient wear resistance caused by excessive metal doping. The coating can meet the dual requirements of wear resistance and antibacterial properties required by endoscopes. Furthermore, in the diamond-like carbon film, the atomic ratio of silver to copper is 1:2 to 2:1.

[0017] By adjusting the ratio of silver and copper, a strong antibacterial effect is maintained while reducing the metal content. This reduces the biocompatibility risks caused by excessive silver and copper ions, making the coating more gentle and safer while meeting the requirements of strong antibacterial effect. Long-term contact with human body cavity mucosa is non-irritating and non-allergenic.

[0018] Furthermore, diamond-like carbon film layer sp 3 The bond content is 30-60%.

[0019] sp 3 With a bond content ranging from 30% to 60%, the coating combines the high hardness of diamond-like carbon with the good toughness of amorphous carbon, ensuring excellent scratch and wear resistance on the endoscope surface while preventing damage from sp. 3Excessive heat can lead to brittle membranes that are prone to chipping and cracking, making them particularly suitable for use with complex curved surfaces, corners, and long-term repeated friction on endoscopes.

[0020] A method for preparing a lightweight, wear-resistant, and antibacterial medical coating includes the following steps: S1: Raw material preparation and pretreatment: Select high-purity target materials: titanium, graphite, silver, and copper; select high-purity argon as the working gas; clean and dry the target workpiece, and load it into the workpiece rack in the vacuum chamber.

[0021] Furthermore, high-purity targets refer to titanium targets, graphite C targets, silver targets, and copper targets with a purity of 99.99%.

[0022] Furthermore, cleaning and drying the target workpiece includes the following sub-steps: S11: Use a neutral medical cleaning agent as the cleaning solution, place the target workpiece into an ultrasonic cleaner, and perform low-power ultrasonic cleaning for 2-8 minutes at 0-45℃. S12: Rinse with two stages of medical ultrapure water overflow for 1-3 minutes each; S13: Dry with hot air at 60~80℃ for 10~15 minutes, without deformation or water stains.

[0023] S2: Ar ion etching: Using a PVD vacuum coating machine, the workpiece holder containing the target workpiece is sent into the vacuum chamber, a vacuum is drawn, and then high-purity Ar is introduced for etching and cleaning.

[0024] Furthermore, the specific parameters of S2 are: back-side vacuum degree ≤ 3.0 × 10⁻⁶ -3 Pa, Ar flow rate set to 10~50 sccm, working gas pressure set to 0.3~0.8 Pa, matrix bias -50~-100 V, time 5~25 min.

[0025] S3: Ti transition layer deposition: Maintaining a vacuum state, magnetron sputtering is performed on the Ti target under an Ar atmosphere to prepare a Ti transition layer on the surface of the target workpiece.

[0026] Furthermore, the specific parameters for S3 are as follows: Ar flow rate set to 15~40 sccm, working gas pressure set to 0.2~0.6 Pa, and Ti target sputtering power set to 1.5~5 W / cm. 2 The substrate bias voltage was set to -50~-100V, and the deposition time was set to 15~40min.

[0027] Furthermore, S3 includes the following sub-steps: S31: Only turn on the Ti target, turn off the C target, Ag target, and Cu target, and deposit for 5~12 minutes to obtain a pure titanium substrate.

[0028] S32: Simultaneously activate Ti, C, Ag, and Cu targets, with Ti target power ranging from 1.5 to 5 W / cm². 2 The linear reduction was 0.2~0.8 W / cm². 2 C target power ranges from 0.2 to 0.8 W / cm². 2 Linear increase to 2~6W / cm 2 The Ag target power was set to 0.1~0.3 W / cm². 2 The Cu power was set to 0.05~0.2W / cm. 2 The deposition time is 12-25 minutes.

[0029] S33: Keep the C target on, the power of the Ag and Cu targets unchanged, and the power of the Ti target continue to decrease until it is turned off.

[0030] S4: Ag and Cu co-doped deposition: After the Ti transition layer is deposited, without breaking the void or cooling down, the parameters are adjusted and graphite C target, Ag target, and Cu target are simultaneously started for co-sputtering to prepare an Ag-Cu-DLC functional layer on the surface of the Ti transition layer.

[0031] Furthermore, the specific parameters for S4 are as follows: working gas pressure set to 0.1~0.5 Pa, graphite C target power set to 2~6 W / cm². 2 The Ag target power was set to 0.5~3W / cm². 2 The Cu target power was set to 0.3~2 W / cm². 2 The substrate bias voltage was set to -50~-200V; the substrate temperature was set to ≤60℃ throughout the process; and the deposition time was set to 30~90min.

[0032] S5: Cooling and Vacuum Breaking: Turn off all target sources and bias power supplies, maintain vacuum and cool to ≤40℃, fill with dry and sterile nitrogen to break the vacuum, and remove the workpiece in a clean environment.

[0033] This preparation method ensures a stable Ti target sputtering process and a high Ti atom ionization rate. The deposited Ti transition layer is dense, pinhole-free, and pore-free. After the Ti transition layer is deposited, no voids are broken or the temperature is lowered before co-sputtering the Ag-Cu-DLC functional layer is directly prepared. This avoids oxidation, contamination, and loss of activation state on the transition layer surface, resulting in a dense, clean, and high-strength interface bond between the two layers. This process solves the problems of easy delamination, peeling, and insufficient adhesion of the coating.

[0034] Graphite C target 2~6W / cm 2 Ag target 0.5~3W / cm 2 Cu target 0.3~2W / cm 2The power ratio ensures that the Ag content is 3.0~5.0 at.%, the Cu content is 1.5~3.0 at.%, and the Ag:Cu atomic ratio is 1:2~2:1 within the design range. This reduces the compositional fluctuations between different workpieces and batches, and solves the problems of inaccurate doping amount, uncontrolled ratio, and large batch performance differences in conventional processes.

[0035] The substrate bias voltage is limited to -50 to -200V to regulate the spline voltage of the DLC film. 3 The bond content is kept stable at 30-60% to avoid excessive bias voltage causing sp. 3 Excessive proportion, high film brittleness leading to easy edge breakage, or excessively low bias voltage causing sp 3 Despite insufficient proportions and inadequate hardness and wear resistance, this solution achieves a balance between high wear resistance and high toughness, adapting to the complex working conditions of repeated insertion, removal, bending, and friction of endoscopes. The substrate temperature remains ≤60℃ throughout the process to prevent thermal deformation of endoscope components and address the issue of Ag and Cu atom diffusion and aggregation caused by high-temperature deposition. This ensures that Ag and Cu antibacterial elements are uniformly dispersed at the nanoscale in the DLC matrix, achieving smooth and slow ion release and long-lasting antibacterial effects. Simultaneously, it does not damage the carbon skeleton structure of the DLC film, balancing mechanical and antibacterial properties. A deposition time range of 30–90 min controls the DLC functional layer thickness to remain stable at 0.25–3.0 μm, ensuring dimensional accuracy and improving wear resistance lifespan.

[0036] Compared with the prior art, the beneficial effects of the present invention are as follows: the coating has a broad-spectrum antibacterial effect and a high antibacterial rate, achieving efficient sterilization with a lower total metal content and reducing endoscope-related cross-infection; at the same time, the coating is chemically inert, has a dense and non-porous structure, is resistant to various disinfection methods, and the titanium transition layer and silver-copper doped structure do not dissolve or fail, avoiding the problem of rapid degradation, failure and peeling of traditional antibacterial coatings after repeated disinfection, while isolating the disinfection medium from the corrosion of the internal metal substrate, ensuring the performance stability of the instrument. Detailed Implementation

[0037] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings: Example

[0038] A lightweight, wear-resistant, and antibacterial medical coating includes a titanium transition layer and a diamond-like carbon film layer located on the surface of the titanium transition layer, wherein the diamond-like carbon film layer contains silver and copper.

[0039] Furthermore, the titanium transition layer also includes a pure titanium underlayer and TiC. X The gradient middle layer, TiC-DLC top layer, and titanium transition layer have a total thickness of 0.05~0.2μm.

[0040] Furthermore, the thickness of the pure titanium substrate is 0.02~0.05μm, and the TiC... X The thickness of the gradient middle layer is 0.05~0.1μm, and the thickness of the TiC-DLC top layer is 0.03~0.5μm; and TiC X The gradient middle layer transitions linearly from a Ti / C atomic ratio of 9:1 to 1:9 near the pure titanium bottom layer and near the TiC-DLC top layer; the TiC X The gradient middle layer and the TiC-DLC top layer are in-situ doped with 0.5-1 at.% Ag and Cu.

[0041] Furthermore, the diamond-like carbon film is an Ag- or Cu-doped diamond-like carbon film with a thickness of 0.25~3.0 μm.

[0042] Furthermore, the silver content in the diamond-like carbon film is 3.0~5.0 at.%, and the copper content is 1.5~3.0 at.%.

[0043] Furthermore, in the diamond-like carbon film, the atomic ratio of silver to copper is 1:2 to 2:1.

[0044] Furthermore, diamond-like carbon film layer sp 3 The bond content is 30-60%. Example

[0045] For the laryngeal blade portion of a video anesthesia laryngoscope, primarily made of stainless steel, aluminum alloy, and polymer materials, the preparation method of this lightweight, wear-resistant, and antibacterial medical coating includes the following steps: S1: Raw material preparation and pretreatment: Select high-purity target materials: titanium, graphite, silver, and copper; select high-purity argon as the working gas; clean and dry the target workpiece, and load it into the workpiece rack in the vacuum chamber.

[0046] Furthermore, high-purity targets refer to titanium targets, graphite C targets, silver targets, and copper targets with a purity of 99.99%.

[0047] Furthermore, cleaning and drying the target workpiece includes the following sub-steps: S11: Use a neutral medical cleaning agent as the cleaning solution, place the target workpiece into an ultrasonic cleaner, and perform low-power ultrasonic cleaning for 5 minutes at 35°C. S12: Rinse with two stages of medical ultrapure water overflow for 3 minutes each; S13: Dryed with 60℃ hot air for 15 minutes, no deformation or water stains.

[0048] S2: Ar ion etching: Using a PVD vacuum coating machine, the workpiece holder containing the target workpiece is sent into the vacuum chamber, a vacuum is drawn, and then high-purity Ar is introduced for etching and cleaning.

[0049] Furthermore, the specific parameters of S2 are as follows: For stainless steel components: Back-end vacuum degree ≤3.0×10 -3 Pa, Ar flow rate set to 30~50 sccm, working gas pressure set to 0.3~0.8 Pa, matrix bias -100V, time 15~20 min; For aluminum alloy components, a back-side vacuum degree of ≤3.0×10 is adopted. -3 Pa, Ar flow rate set to 25~40 sccm, working gas pressure set to 0.4~0.8 Pa, matrix bias -100V, time 12~18 min; For polymer material components, a back-side vacuum degree of ≤3.0×10 is adopted. -3 Pa, Ar flow rate set to 10~50 sccm, working gas pressure set to 0.6~0.8 Pa, matrix bias -50V, time 10~30 min; For components made of stainless steel, aluminum alloy, and polymer materials that cannot be disassembled, a back-side vacuum of ≤3.0×10 is used. -3 Pa, Ar flow rate set to 30 sccm, working gas pressure set to 0.6 Pa, matrix bias -350 V, time 15 min.

[0050] S3: Ti transition layer deposition: Maintaining a vacuum state, magnetron sputtering is performed on the Ti target under an Ar atmosphere to prepare a Ti transition layer on the surface of the target workpiece.

[0051] Furthermore, S3 includes the following sub-steps: S31: Only turn on the Ti target, turn off the C target, Ag target, and Cu target, and deposit for 5~12 minutes to obtain a pure titanium substrate.

[0052] S32: Simultaneously activate Ti, C, Ag, and Cu targets, with Ti target power ranging from 1.5 to 5 W / cm². 2 The linear reduction was 0.2~0.8 W / cm². 2 C target power ranges from 0.2 to 0.8 W / cm². 2 Linear increase to 2~6W / cm 2 The Ag target power was set to 0.1~0.3 W / cm². 2 The Cu power was set to 0.05~0.2W / cm. 2 The deposition time is 12-25 minutes.

[0053] S33: Keep the C target on, the power of the Ag and Cu targets unchanged, and the power of the Ti target continue to decrease until it is turned off.

[0054] Furthermore, the specific parameters of S3 for different components are as follows: Stainless steel components: S31 deposition time 8 min; S32 Ti target power from 3 W / cm 2 Linear reduction to 0.5 W / cm 2 C target power from 0.5W / cm 2 Linear increase to 4W / cm 2 Ag target power 0.2 W / cm 2 Cu target power 0.1 W / cm 2 The deposition time was 18 min; the Ti target power in S33 was reduced to 0 and then turned off.

[0055] Aluminum alloy components: S31 deposition time 6 min; Ti target power in S32 from 2 W / cm 2 The linear reduction was 0.4 W / cm². 2 C target power from 0.4 W / cm 2 Linear increase to 3W / cm 2 Ag target power 0.15 W / cm 2 Cu target power 0.08 W / cm 2 The deposition time was 15 min; the Ti target power in S33 was reduced to 0 and then turned off.

[0056] Polymer material components: S31 deposition time 10 min; Ti target power in S32 from 4 W / cm 2 The linear reduction was 0.6 W / cm². 2 C target power from 0.6 W / cm 2 Linear increase to 5W / cm 2 Ag target power 0.25 W / cm 2 Cu target power 0.15 W / cm 2 The deposition time was 22 min; the Ti target power in S33 was reduced to 0 and then turned off.

[0057] Combined components: S31 deposition time 7 min; S32 Ti target power from 2.5 W / cm² 2 Linear reduction to 0.5 W / cm 2 C target power from 0.5W / cm 2 Linear increase to 3.5W / cm 2 Ag target power 0.2 W / cm 2 Cu target power 0.1 W / cm 2 The deposition time was 16 min; the Ti target power in S33 was reduced to 0 and then shut off.

[0058] S4: Ag and Cu co-doped deposition: After the Ti transition layer is deposited, without breaking the void or cooling down, the parameters are adjusted and graphite C target, Ag target, and Cu target are simultaneously started for co-sputtering to prepare an Ag-Cu-DLC functional layer on the surface of the Ti transition layer.

[0059] Furthermore, the specific parameters for S4 are as follows: working gas pressure set to 0.5 Pa, graphite C target power set to 2.5 W / cm². 2 The Ag target power was set to 2 W / cm². 2 The Cu target power was set to 1.5 W / cm². 2 The substrate bias voltage was set to -200V; the substrate temperature was set to ≤60℃ throughout the process; and the deposition time was set to 60min.

[0060] S5: Cooling and Vacuum Breaking: Turn off all target sources and bias power supplies, maintain vacuum and cool to ≤40℃, fill with dry and sterile nitrogen to break the vacuum, and remove the workpiece in a clean environment.

[0061] The above preparation method yields a lightweight, wear-resistant, and antibacterial medical coating, comprising a titanium transition layer and a diamond-like carbon film layer located on the surface of the titanium transition layer, wherein the diamond-like carbon film layer contains silver and copper.

[0062] Furthermore, the total thickness of the titanium transition layer is 0.15 μm, consisting of a pure titanium base layer and TiC. X The structure consists of a gradient middle layer and a TiC-DLC top layer; the pure titanium bottom layer is 0.03 μm thick and has a titanium content of 99.95 at.%; TiC X The gradient middle layer has a thickness of 0.08 μm, and the Ti / C atomic ratio linearly transitions from 9:1 to 1:9 from near the pure titanium bottom layer to near the TiC-DLC top layer; the TiC-DLC top layer has a thickness of 0.04 μm; TiC X The gradient middle layer and the TiC-DLC top layer are in-situ doped with 0.8 at.% Ag and Cu.

[0063] Furthermore, the diamond-like carbon film is an Ag- and Cu-doped diamond-like carbon film with a thickness of 0.7 μm.

[0064] Furthermore, the diamond-like carbon film contains 4 at.% silver and 2.5 at.% copper.

[0065] Furthermore, in the diamond-like carbon film, the atomic ratio of silver to copper is 1.6:1.

[0066] Furthermore, diamond-like carbon film layer sp 3 The bond content is 45%.

[0067] The laryngoscope blade of a video anesthesia laryngoscope is made of stainless steel, aluminum alloy, and polymer materials. Its main use is to lift the patient's epiglottis to expose the glottis, guide medical staff to accurately perform airway intubation for anesthesia or emergency treatment, and can also be used for oral examination and treatment. Laryngeal blades come into contact with the inside of the oral cavity. Traditional laryngeal blades often have teeth marks on their surface due to collisions or friction with the teeth, which affects their lifespan with repeated use. The abrasion resistance of this coating enhances the abrasion resistance of the laryngeal blade, increasing its lifespan. Secondly, traditional reusable laryngeal blades require repeated sterilization. After each use, the surface of the blade retains the patient's bodily fluids. Traditional laryngeal blades do not have antibacterial properties, so they need to be soaked or subjected to low-temperature plasma sterilization before reuse. This process can lead to incomplete sterilization and increase the risk of cross-infection during secondary use. The coating prepared in this embodiment has high antibacterial properties, giving the laryngeal blade its own antibacterial characteristics. After use, soaking or low-temperature plasma sterilization ensures more thorough sterilization. At the same time, this coating is chemically inert, has a dense and non-porous structure, is resistant to various sterilization methods, does not dissolve or become ineffective, and isolates the internal substrate from the corrosion of the sterilization medium, ensuring the stability of the instrument's performance. This reduces the risk of secondary cross-infection and extends the product's lifespan. Example

[0068] For the insertion part of an electronic bronchoscope, which needs to enter the subglottic trachea, the outer surface material is TPU and fluororubber. The preparation method of this lightweight, wear-resistant, and antibacterial medical coating includes the following steps: S1: Raw material preparation and pretreatment: Select high-purity target materials: titanium, graphite, silver, and copper; select high-purity argon as the working gas; clean and dry the target workpiece, and load it into the workpiece rack in the vacuum chamber.

[0069] Furthermore, high-purity targets refer to titanium targets, graphite C targets, silver targets, and copper targets with a purity of 99.99%.

[0070] Furthermore, cleaning and drying the target workpiece includes the following sub-steps: S11: Use a neutral medical cleaning agent as the cleaning solution, place the target workpiece into an ultrasonic cleaner, and perform low-power ultrasonic cleaning for 5 minutes at 25°C. S12: Rinse with two-stage medical ultrapure water overflow for 2 minutes each; S13: Dryed with 50℃ hot air for 10 minutes, no deformation or water stains.

[0071] S2: Ar ion etching: Using a PVD vacuum coating machine, the workpiece holder containing the target workpiece is sent into the vacuum chamber, a vacuum is drawn, and then high-purity Ar is introduced for etching and cleaning.

[0072] Furthermore, the specific parameters of S2 are as follows: For TPU and fluororubber components, a back-side vacuum degree of ≤3.0×10 is adopted. -3 Pa, Ar flow rate set to 25 sccm, working gas pressure set to 0.8 Pa, matrix bias -100 V, time 8 min.

[0073] S3: Ti transition layer deposition: Maintaining a vacuum state, magnetron sputtering is performed on the Ti target under an Ar atmosphere to prepare a Ti transition layer on the surface of the target workpiece.

[0074] S31: Only Ti target is turned on, C target, Ag target and Cu target are turned off, deposition time is 8 min, pure titanium bottom layer is obtained; S32: Simultaneously activate Ti, C, Ag, and Cu targets, with Ti target power starting at 1.5 W / cm². 2 Linear reduction to 0.5 W / cm 2 C target power from 0.5W / cm 2 Linear increase to 2.5W / cm 2 The Ag target power was set to 0.2 W / cm². 2 The Cu target power was set to 0.1 W / cm². 2 Deposition time: 12 min; S33: Keep the C target on, the power of the Ag and Cu targets unchanged, and the power of the Ti target continue to decrease until it is turned off to complete the gradient deposition of the Ti transition layer. This ensures a smooth transition between the transition layer and the subsequent Ag-Cu-DLC functional layer, while avoiding damage to the TPU and fluororubber matrix.

[0075] S4: Ag and Cu co-doped deposition: After the Ti transition layer is deposited, without breaking the void or cooling down, the parameters are adjusted and graphite C target, Ag target, and Cu target are simultaneously started for co-sputtering to prepare an Ag-Cu-DLC functional layer on the surface of the Ti transition layer.

[0076] Furthermore, the specific parameters for S4 are as follows: working gas pressure set to 0.5 Pa, graphite C target power set to 2.5 W / cm². 2 The Ag target power was set to 1 W / cm². 2 The Cu target power was set to 1 W / cm. 2 The substrate bias voltage was set to -50V; the substrate temperature was set to ≤60℃ throughout the process; and the deposition time was set to 50min.

[0077] S5: Cooling and Vacuum Breaking: Turn off all target sources and bias power supplies, maintain vacuum and cool to ≤40℃, fill with dry and sterile nitrogen to break the vacuum, and remove the workpiece in a clean environment.

[0078] The insertion section of an electronic bronchoscope provides the necessary imaging and working channel for observation, diagnosis, imaging, and treatment of the trachea and bronchi. During use, it needs to pass through the patient's teeth and is often used in conjunction with other surgical instruments. The most common failure rate is damage to the outer skin of the insertion section. Damage leads to incomplete sterilization and affects some functions, rendering the product unusable. This coating's abrasion-resistant properties increase the wear resistance of the insertion section's surface, significantly reducing damage from external forces and protecting its toughness and strength. After use, further immersion or low-temperature plasma sterilization is performed. The antibacterial properties of this coating ensure more thorough sterilization, reducing the risk of secondary cross-infection and extending the product's lifespan.

[0079] The above preparation method yields a lightweight, wear-resistant, and antibacterial medical coating, comprising a titanium transition layer and a diamond-like carbon film layer located on the surface of the titanium transition layer, wherein the diamond-like carbon film layer contains silver and copper.

[0080] Furthermore, the total thickness of the titanium transition layer is 0.15 μm, consisting of a pure titanium base layer and TiC. X The structure consists of a gradient middle layer and a TiC-DLC top layer; the titanium content is 99.95 at.%, the pure titanium bottom layer is 0.03 μm thick, and the TiC... X The thickness of the gradient middle layer is 0.08 μm, and the thickness of the TiC-DLC top layer is 0.04 μm; TiC X The gradient middle layer transitions linearly from a Ti / C atomic ratio of 9:1 to 1:9 near the pure titanium bottom layer and near the TiC-DLC top layer; TiC X The gradient middle layer and the TiC-DLC top layer are in-situ doped with 0.8 at.% Ag and Cu.

[0081] Furthermore, the diamond-like carbon film is an Ag- and Cu-doped diamond-like carbon film with a thickness of 0.55 μm.

[0082] Furthermore, the silver content in the diamond-like carbon film is 4.0 at.% and the copper content is 2.2 at.%.

[0083] Furthermore, in the diamond-like carbon film, the atomic ratio of silver to copper is 1.8:1.

[0084] Furthermore, diamond-like carbon film layer sp 3 Bond content is 45%. Example

[0085] Five samples were prepared. All samples used the same substrate (316L medical stainless steel) and the same high-purity target material: titanium target, graphite C target, silver target and copper target, all with a purity of 99.99%.

[0086] S1: Raw material preparation and pretreatment: Select high-purity target materials: titanium, graphite, silver, and copper; select high-purity argon as the working gas; clean and dry the target workpiece, and load it into the workpiece rack in the vacuum chamber.

[0087] Furthermore, high-purity targets refer to titanium targets, graphite C targets, silver targets, and copper targets with a purity of 99.99%.

[0088] Furthermore, cleaning and drying the target workpiece includes the following sub-steps: S11: Use a neutral medical cleaning agent as the cleaning solution, place the target workpiece into an ultrasonic cleaner, and perform low-power ultrasonic cleaning for 5 minutes at 35°C. S12: Rinse with two-stage medical ultrapure water overflow for 2 minutes each; S13: Dryed with 60℃ hot air for 15 minutes, no deformation or water stains.

[0089] S2: Ar ion etching: Using a PVD vacuum coating machine, the workpiece holder containing the target workpiece is sent into the vacuum chamber, a vacuum is drawn, and then high-purity Ar is introduced for etching and cleaning.

[0090] S3: Ti transition layer deposition: Maintaining a vacuum state, magnetron sputtering is performed on the Ti target under an Ar atmosphere to prepare a Ti transition layer on the surface of the target workpiece.

[0091] S31: Only enable the Ti target, and disable the C, Ag, and Cu targets to obtain a pure titanium substrate.

[0092] S32: Simultaneously activate Ti, C, Ag, and Cu targets, with Ti target power ranging from 1.5 to 5 W / cm². 2 The linear reduction was 0.2~0.8 W / cm². 2 C target power ranges from 0.2 to 0.8 W / cm². 2 Linear increase to 2~6W / cm 2 The Ag target power was set to 0.1~0.3 W / cm². 2 The Cu power was set to 0.05~0.2W / cm. 2 The deposition time is 12-25 minutes.

[0093] S33: Keep the C target on, the power of the Ag and Cu targets unchanged, and the power of the Ti target continue to decrease until it is turned off.

[0094] S4: Ag and Cu co-doped deposition: After the Ti transition layer is deposited, without breaking the void or cooling down, the parameters are adjusted and graphite C target, Ag target, and Cu target are simultaneously started for co-sputtering to prepare an Ag-Cu-DLC functional layer on the surface of the Ti transition layer.

[0095] The specific parameters for sample 1: S2 are as follows: a back-bottom vacuum of 2.0 × 10⁻⁶.-3 Pa, Ar flow rate set to 30 sccm, working gas pressure set to 0.5 Pa, matrix bias -100 V, time 15 min.

[0096] The specific parameters for S3 are: Ar flow rate set to 30 sccm, working gas pressure set to 0.6 Pa, substrate bias set to -60 V, and total deposition time set to 30 min. S31: Only Ti target is turned on, C target, Ag target and Cu target are turned off, deposition time is 5 min, pure titanium substrate is obtained; S32: Simultaneously activate Ti, C, Ag, and Cu targets, with Ti target power starting at 2.5 W / cm². 2 The linear reduction was 0.6 W / cm². 2 C target power from 0.4 W / cm 2 Linear increase to 3.0 W / cm 2 The Ag target power was set to 0.2 W / cm². 2 The Cu target power was set to 0.1 W / cm². 2 Deposition time: 20 min; S33: Keep the C target on, the power of the Ag and Cu targets unchanged, and continue to reduce the power of the Ti target to the off. The deposition time is 5 minutes to complete the deposition of the Ti transition layer.

[0097] The specific parameters for S4 are as follows: working pressure set to 0.3 Pa, graphite C target power set to 3.0 W / cm². 2 The Ag target power was set to 0.8 W / cm². 2 The Cu target power was set to 0.5 W / cm². 2 The substrate bias voltage was set to -60V; the substrate temperature was set to ≤60℃ throughout the process; and the deposition time was set to 60min.

[0098] Sample 2: The specific parameters of S2 are as follows: a back-bottom vacuum of 2.2 × 10⁻⁶. -3 Pa, Ar flow rate set to 32 sccm, working gas pressure set to 0.5 Pa, matrix bias -100 V, time 15 min.

[0099] The specific parameters for S3 are: Ar flow rate set to 30 sccm, working gas pressure set to 0.6 Pa, substrate bias set to -60 V, and total deposition time set to 30 min. S31: Only Ti target is turned on, C target, Ag target and Cu target are turned off, deposition time is 5 min, pure titanium substrate is obtained; S32: Simultaneously activate Ti, C, Ag, and Cu targets; Ti target power starts at 2.6 W / cm². 2 The linear reduction was 0.7 W / cm². 2 C target power from 0.4 W / cm2 Linear increase to 3.0 W / cm 2 The Ag target power was set to 0.22 W / cm². 2 The Cu target power was set to 0.12 W / cm². 2 Deposition time: 20 min; S33: Keep the C target on, the power of the Ag and Cu targets unchanged, and continue to reduce the power of the Ti target to the off. The deposition time is 5 minutes to complete the deposition of the Ti transition layer.

[0100] The specific parameters for S4 are as follows: working pressure set to 0.3 Pa, graphite C target power set to 3.0 W / cm². 2 The Ag target power was set to 0.85 W / cm². 2 The Cu target power was set to 0.55 W / cm². 2 The substrate bias voltage was set to -150V; the substrate temperature was set to ≤60℃ throughout the process; and the deposition time was set to 60min.

[0101] The specific parameters for sample 3: S2 are as follows: a back-bottom vacuum of 2.5 × 10⁻⁶. -3 Pa, Ar flow rate set to 25 sccm, working gas pressure set to 0.6 Pa, matrix bias -350 V, time 12 min.

[0102] The specific parameters for S3 are: Ar flow rate set to 25 sccm, working gas pressure set to 0.5 Pa, substrate bias set to -50 V, and total deposition time set to 25 min. S31: Only Ti target is turned on, C target, Ag target and Cu target are turned off, deposition time is 4 min, pure titanium bottom layer is obtained; S32: Simultaneously activate Ti, C, Ag, and Cu targets, with Ti target power starting at 2.0 W / cm². 2 Linear reduction to 0.5 W / cm 2 C target power from 0.3W / cm 2 Linear increase to 2.5W / cm 2 The Ag target power was set to 0.18 W / cm². 2 The Cu target power was set to 0.08 W / cm². 2 The deposition time was 18 minutes.

[0103] The specific parameters for S4 are as follows: working pressure set to 0.5 Pa, graphite C target power set to 2.5 W / cm². 2 The Ag target power was set to 0.5 W / cm². 2 The Cu target power was set to 0.3 W / cm². 2 The substrate bias voltage was set to -60V; the substrate temperature was set to ≤60℃ throughout the process; and the deposition time was set to 50min.

[0104] The specific parameters for sample 4: S2 are as follows: a back-bottom vacuum of 1.8 × 10⁻⁶. -3 Pa, Ar flow rate set to 35 sccm, working gas pressure set to 0.4 Pa, matrix bias -50 V, time 18 min.

[0105] The specific parameters for S3 are: Ar flow rate set to 30 sccm, working gas pressure set to 0.6 Pa, substrate bias set to -70 V, and total deposition time set to 32 min. S31: Only Ti target is turned on, C target, Ag target and Cu target are turned off, deposition time is 7 min, pure titanium substrate is obtained; S32: Simultaneously activate Ti, C, Ag, and Cu targets; Ti target power starts at 2.8 W / cm². 2 The linear reduction was 0.8 W / cm². 2 The target power (C) increased linearly from 0.5 W / cm² to 4.0 W / cm². 2 The Ag target power was set to 0.25 W / cm². 2 The Cu target power was set to 0.15 W / cm². 2 Deposition time: 22 min; S33: Keep the C target on, the power of the Ag and Cu targets unchanged, and continue to reduce the power of the Ti target to the off. The deposition time is 3 minutes to complete the deposition of the Ti transition layer.

[0106] The specific parameters for S4 are as follows: working pressure set to 0.2 Pa, graphite C target power set to 4.0 W / cm². 2 The Ag target power was set to 1.2 W / cm². 2 The Cu target power was set to 0.7 W / cm². 2 The substrate bias voltage was set to -180V; the substrate temperature was set to ≤60℃ throughout the process; and the deposition time was set to 70min.

[0107] The specific parameters for sample 5: S2 are as follows: a back-bottom vacuum of 2.3 × 10⁻⁶. -3 Pa, Ar flow rate set to 28 sccm, working pressure set to 0.5 Pa, matrix bias -50 V, time 14 min.

[0108] The specific parameters for S3 are as follows: Ar flow rate set to 28 sccm, working gas pressure set to 0.5 Pa, and Ti target sputtering power set to 2.2 W / cm². 2 The substrate bias voltage was set to -55V, and the total deposition time was 28 minutes. S31: Only Ti target is turned on, C target, Ag target and Cu target are turned off, deposition time is 6 min, pure titanium bottom layer is obtained; S32: Simultaneously activate Ti, C, Ag, and Cu targets, with Ti target power starting at 2.2 W / cm². 2 The linear reduction was 0.6 W / cm². 2 C target power from 0.4 W / cm 2 Linear increase to 2.8W / cm 2 The Ag target power was set to 0.2 W / cm². 2 The Cu target power was set to 0.1 W / cm². 2 The deposition time was 19 minutes. S33: Keep the C target on, the power of the Ag and Cu targets unchanged, and continue to reduce the power of the Ti target to the off. The deposition time is 3 minutes to complete the deposition of the Ti transition layer.

[0109] The specific parameters for S4 are as follows: working pressure set to 0.4 Pa, graphite C target power set to 2.8 W / cm². 2 The Ag target power was set to 0.65 W / cm². 2 The Cu target power was set to 0.4 W / cm². 2 The substrate bias voltage was set to -100V; the substrate temperature was set to ≤60℃ throughout the process; and the deposition time was set to 55min.

[0110] S5: Cooling and Vacuum Breaking: Turn off all target sources and bias power supplies, maintain vacuum and cool to ≤40℃, fill with dry and sterile nitrogen to break the vacuum, and remove the workpiece in a clean environment.

[0111] Samples 1-5 were subjected to S6 performance testing, which included the following steps: S61: Interface Bonding Performance Test: The adhesion test is conducted using the cross-cut adhesion test. The sample is fixed flat on a rigid platform. A cross-cut adhesion tester is used to create a 6×6 grid perpendicular to the coating surface with a uniform and steady force. The grid spacing is 1mm, and the blade must completely penetrate the coating to the substrate surface. A soft brush is used to gently sweep along the diagonal of the grid 5 times to remove coating debris. 3M medical tape is then completely applied to the grid area. Air bubbles are removed by pressing evenly with the fingers. After standing for 90 seconds, the tape is peeled off smoothly and quickly at a 60° angle to the coating surface. The extent of coating peeling off in the grid area is observed through a magnifying glass.

[0112] S62: Adhesion test after long-term immersion: The coating sample is completely immersed in a simulated body fluid at a constant temperature of 37°C and left to soak for 30 days. Fresh simulated body fluid is replaced every 7 days. After soaking, the sample is taken out, rinsed with ultrapure water, dried with sterile cold air, and subjected to a cross-cut adhesion test according to the method in S61 to determine the adhesion level.

[0113] S63: Wear resistance test: A multi-functional friction and wear tester was used. The wear pair was a medical-grade 316L stainless steel standard ball (diameter 4mm, roughness Ra≤0.02μm). The normal load was 5N, the reciprocating stroke was 10mm, the reciprocating frequency was 2Hz, and the test time was 60min. The test environment was divided into dry friction (25℃ standard environment) and 37℃ constant temperature physiological saline environment (simulating human body fluid). The sample is flattened and fixed on the sample stage of the friction testing machine, and the grinding ball is fixed in the fixture to ensure that the grinding surface is perpendicular to the coating surface. When testing in a physiological saline environment, the sample must be completely immersed in physiological saline at a constant temperature of 37°C to ensure that the friction is in a liquid environment throughout the process. Start the testing machine and test according to the above parameters. The instrument collects friction coefficient data in real time, takes the average friction coefficient during the stable phase, and calculates the wear rate.

[0114] S64: Antibacterial rate test: The film contact method was used: 100 μL of bacterial suspension was evenly dropped onto the sample surface and covered with a sterile polyethylene film to ensure complete contact between the bacterial suspension and the sample surface without air bubbles; the inoculated sample was placed in a sterile petri dish and incubated at 37℃ and relative humidity ≥90% for 24 h; after incubation, the sample and film were rinsed with 10 mL of sterile physiological saline, the eluent was collected, serially diluted and spread on nutrient agar plates, and incubated at 37℃ for 24 h, and the number of colonies on the plates was counted; Antibacterial rate (%) = ((number of viable bacteria in blank control - number of viable bacteria in sample) / number of viable bacteria in blank control) × 100%.

[0115] S65: Ag and Cu ion leaching test: Inductively coupled plasma mass spectrometry was used. The immersion medium was simulated body fluid, and the leaching ratio was sample coating surface area / immersion medium volume = 3 cm³. 2 / mL; The coated sample was completely immersed in the extraction medium and kept at a constant temperature of 37℃ for 7 days. A blank medium control group was set up. After soaking, the upper layer of extract was taken, filtered through a 0.22μm filter membrane, and the concentrations of Ag and Cu elements in the extract were tested by ICP-MS. The blank control group was tested simultaneously. Data processing: Sample ion dissolution amount = sample extract concentration - blank control group concentration, in mg / L.

[0116] S66: Comparative Example 1: No Ti transition layer; Comparative Example 2: No Ag or Cu doping.

[0117] Sample 1 Level 0 Level 0 0.13 0.11 <![CDATA[1.8×10 -7 ]]> 99.7 99.8 0.058 0.026 Sample 2 Level 0 Level 0 0.14 0.12 <![CDATA[1.9×10 -7 ]]> 99.6 99.7 0.059 0.027 Sample 3 Level 0 Level 0 0.16 0.14 <![CDATA[2.8×10 -7 ]]> 99.2 99.3 0.041 0.019 Sample 4 Level 0 Level 0 0.10 0.09 <![CDATA[1.3×10 -7 ]]> 99.9 99.9 0.085 0.039 Sample 5 Level 0 Level 0 0.13 0.11 <![CDATA[2.3×10 -7 ]]> 99.5 99.7 0.053 0.035 Comparative Example 1 Level 2 Level 3 0.22 0.20 <![CDATA[9.2×10 -6 ]]> 99.6 99.5 0.057 0.025 Comparative Example 2 Level 1 Level 1 0.15 0.14 <![CDATA[3.6×10 -7 ]]> 11.5 12.3 Not detected Not detected Additional notes: 1. Adhesion grade determination using the cross-cut adhesion test: Grade 0 (no peeling), Grade 1 (slight peeling at the grid edges, peeling area < 5%), Grade 2 (peeling area 5%~15%), Grade 3 (peeling area 15%~35%); 2. Wear rate calculation follows step S63, calculated by scanning the wear marks using a laser confocal profilometer; 3. Ion dissolution tests deducted the concentration of the blank control group, meeting medical safety limits (Ag ≤ 0.1 mg / L, Cu ≤ 0.05 mg / L); 4. The viable bacteria count in the blank control group for the antibacterial rate test was 1 × 10⁻⁶. 6 ~2×10 6 CFU / mL.

[0118] The data obtained from the performance test was processed to produce the table above. The data in the table shows that the coating adheres well and is not easy to fall off under dry storage and normal use conditions; it also has excellent wear resistance and is not prone to scratches or damage; at the same time, it has a high antibacterial rate, reducing cross-infection related to endoscopes; the silver and copper doped structure does not dissolve or fail, avoiding the problem of rapid degradation, failure and peeling of traditional antibacterial coatings after repeated disinfection, while isolating the internal metal substrate from the disinfection medium, ensuring the stability of the instrument's performance.

[0119] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A lightweight, wear-resistant, and antibacterial medical coating, characterized in that: It includes a titanium transition layer and a diamond-like carbon film layer located on the surface of the titanium transition layer, the diamond-like carbon film layer containing silver and copper.

2. The lightweight, wear-resistant, antibacterial medical coating as described in claim 1, characterized in that: The titanium transition layer also includes a pure titanium underlayer and TiC. X The gradient middle layer, TiC-DLC top layer, and titanium transition layer have a total thickness of 0.05~0.2μm.

3. The lightweight, wear-resistant, antibacterial medical coating as described in claim 1, characterized in that: The diamond-like carbon film is an Ag- or Cu-doped diamond-like carbon film with a thickness of 0.25~3.0 μm.

4. The lightweight, wear-resistant, and antibacterial medical coating as described in claim 1, characterized in that: The diamond-like carbon film contains 3.0~5.0 at.% silver and 1.5~3.0 at.% copper.

5. The lightweight, wear-resistant, antibacterial medical coating and its preparation method as described in claim 1, characterized in that: In the diamond-like carbon film, the atomic ratio of silver to copper is 1:2 to 2:

1.

6. The lightweight, wear-resistant, antibacterial medical coating and its preparation method as described in claim 1, characterized in that: The diamond-like carbon film layer sp 3 The bond content is 30-60%.

7. The method for preparing the lightweight, wear-resistant, and antibacterial medical coating as described in any one of claims 1 to 6, characterized in that: Includes the following steps: S1: Raw material preparation and pretreatment: Select high-purity target materials: titanium, graphite, silver, and copper; High-purity argon is selected as the working gas; the target workpiece is cleaned, dried, and placed into the workpiece holder in the vacuum chamber. The high-purity target material refers to titanium target, graphite C target, silver target, and copper target with a purity of 99.99%. S2: Ar ion etching: Using a PVD vacuum coating machine, the workpiece holder containing the target workpiece is sent into the vacuum chamber, a vacuum is drawn, and then high-purity Ar is introduced for etching and cleaning. S3: Ti transition layer deposition: Maintaining a vacuum state, magnetron sputtering is performed on the Ti target under an Ar atmosphere to prepare a Ti transition layer on the surface of the target workpiece. S4: Ag and Cu co-doping deposition: After the Ti transition layer is deposited, without breaking the void or cooling down, the parameters are adjusted, and graphite C target, Ag target and Cu target are simultaneously started for co-sputtering to prepare an Ag-Cu-DLC functional layer on the surface of the Ti transition layer. S5: Cooling and Vacuum Breaking: Turn off all target sources and bias power supplies, maintain vacuum and cool to ≤40℃, fill with dry and sterile nitrogen to break the vacuum, and remove the workpiece in a clean environment.

8. The method for preparing the lightweight, wear-resistant, and antibacterial medical coating as described in claim 7, characterized in that: The specific parameters for S2 are: back-side vacuum degree ≤ 3.0 × 10⁻⁶ -3 Pa, Ar flow rate set to 10~50 sccm, working gas pressure set to 0.3~0.8 Pa, matrix bias voltage -200~-600 V, time 5~25 min.

9. The method for preparing the lightweight, wear-resistant, and antibacterial medical coating as described in claim 7, characterized in that: S3 includes the following sub-steps: S31: Only turn on the Ti target, turn off the C target, Ag target, and Cu target, and deposit for 5~12 minutes to obtain a pure titanium substrate; S32: Simultaneously activate Ti, C, Ag, and Cu targets, with Ti target power ranging from 1.5 to 5 W / cm². 2 The linear reduction was 0.2~0.8 W / cm². 2 C target power ranges from 0.2 to 0.8 W / cm². 2 Linear increase to 2~6W / cm 2 The Ag target power was set to 0.1~0.3 W / cm². 2 The Cu power was set to 0.05~0.2W / cm. 2 Deposition time: 12-25 min; S33: Keep the C target on, the power of the Ag and Cu targets unchanged, and the power of the Ti target continue to decrease until it is turned off.

10. The method for preparing the lightweight, wear-resistant, and antibacterial medical coating as described in claim 7, characterized in that: The specific parameters for S4 are as follows: working gas pressure is set to 0.1~0.5Pa, and graphite C target power is set to 2~6W / cm². 2 The Ag target power was set to 0.5~3Wcm. 2 The Cu target power was set to 0.3~2 W / cm². 2 The substrate bias voltage was set to -50 to -200V; the substrate temperature was set to ≤60℃ throughout the process; and the deposition time was set to 30 to 90 minutes.