Manufacturing method of ligation clip and ligation clip

Abstract

The invention discloses a manufacturing method of a ligation clip and the ligation clip, the ligation clip comprises a V-shaped ligation clip body, the ligation clip body is made of a high polymer material, the ligation clip body is provided with a first clip arm, a second clip arm and an elastic connecting part, the end part of the first clip arm is provided with a lock hook, and the end part of the second clip arm is provided with a lock catch; the ligature clip further comprises metal wires arranged in the first clip arm, the second clip arm and the elastic connecting portion, a plurality of grooves are formed in the outer surfaces of the metal wires, the ligature clip body wraps the metal wires through an injection molding process, and anchoring portions extending into the grooves are arranged in the ligature clip body. According to the ligation clamp, a rigid-flexible composite implementation mechanism is adopted, the metal wire serves as a rigid core, the ligation clamp body made of a high polymer material serves as a flexible base body, in addition, mutual movement of the ligation clamp body and the metal wire is effectively prevented through combination of the groove and the anchoring part, the mechanical property bottleneck of a traditional single-material ligation clamp is broken through, and the durability of the ligation clamp is improved.

Description

Technical Field

[0001] This invention relates to the field of medical devices, and more specifically to a method for manufacturing a ligation clip and the ligation clip itself. Background Technology

[0002] Disposable ligation clips, also known as closure clips, are mainly used to clamp tubular structures such as blood vessels, lymphatic vessels, and bile ducts to achieve hemostasis or block the flow of contents. They are widely used in endoscopic and open surgeries, replacing traditional suture ligation, and are characterized by convenient operation, minimal trauma, and high efficiency.

[0003] Based on the material, ligation clips can be divided into polymer material ligation clips and metal ligation clips; based on whether they can be degraded and absorbed in the human body, they can be divided into absorbable ligation clips and non-absorbable ligation clips.

[0004] Traditional metal ligation clips (usually titanium or stainless steel clips) provide strong initial clamping force due to their high hardness and material stability, resulting in more stable ligated tissue. However, they have poor tissue compatibility, which may cause rejection and inflammation risks. They are particularly unsuitable for luminal tissues with significant inflammation, edema, or fragility, and cannot handle larger luminals.

[0005] Polymer ligation clips have a wide range of applications; they have good biocompatibility, with no tissue rejection, hyperplasia, or granulomas; and they maintain the activity of tissue stumps. However, long-term retention may lead to a decrease in clamping force due to tissue contraction or activity, resulting in poor long-term stability. For example, the elastic modulus of traditional pure polymer clips (POM) is around 3 GPa, only about 3% of that of titanium alloys, which cannot meet the rigidity requirements of large vessel clamping alone. For example, arterial clamping requires greater than 5 GPa. Traditional designs may use reinforcing ribs or thickened clip walls, but the roots of the reinforcing ribs may experience significant stress concentration. The stress peak at the connection between the reinforcing rib and the matrix can reach 3-5 times the overall average stress. Furthermore, POM material has high notch sensitivity, and scratches may appear at the edges of thickened clip walls, reducing its fracture toughness. It may also conflict with the dimensions of existing instruments, which is not conducive to clinical operation. Summary of the Invention

[0006] To address the above-mentioned problems and overcome at least one deficiency, this invention proposes a method for manufacturing a ligation clip and a ligation clip in general.

[0007] The technical solution adopted in this invention is as follows: A ligation clip includes a V-shaped ligation clip body made of a polymer material. The ligation clip body has a first clamping arm, a second clamping arm, and an elastic connecting portion connecting the first clamping arm and the second clamping arm. The end of the first clamping arm away from the elastic connecting portion has a locking hook, and the end of the second clamping arm away from the elastic connecting portion has a locking buckle. When the first clamping arm and the second clamping arm are brought close together, the locking hook and the locking buckle cooperate to achieve locking. It also includes a metal wire built into the first clamping arm, the second clamping arm, and the elastic connecting portion. The outer surface of the metal wire has multiple grooves. The ligation clip body is coated on the metal wire by injection molding. The ligation clip body has an anchoring portion extending into the grooves.

[0008] The ligation clip of this application adopts a rigid-flexible composite mechanism, with a metal wire as the rigid core and a polymer material ligation clip body as the flexible matrix. In addition, the combination of grooves and anchoring parts effectively prevents the ligation clip body and the metal wire from moving relative to each other. The ligation clip of this application can achieve two major performances. First, it achieves a combination of rigidity and flexibility in mechanical properties. The metal wire provides the precise rigidity and stability required for surgery, while the ligation clip body absorbs the dynamic load during physiological activities, reducing the damage to tissues caused by the ligation clip and giving it a wider clamping range. The two work together to achieve a balance between bending stiffness and elastic deformation capacity. Second, it solves the problem of poor biocompatibility of metal materials. The polymer material is highly inert and has good tissue compatibility. The polymer material completely encapsulates the metal wire and comes into direct contact with human tissue, which can reduce the risk of rejection and inflammation.

[0009] In practical applications, the ligation clip body has a receiving groove for accommodating the metal wire, and the anchoring part is located on the side wall of the receiving groove.

[0010] Preferably, the metal wire is pure titanium wire (medical-grade TA1), and the polymer material is high-grade polyoxymethylene (POM). POM material is ISO 10993 biocompatibility certified and possesses both high rigidity and low moisture absorption. POM has good mechanical properties, excellent creep resistance and stress relaxation ability, and its fatigue resistance is the highest among thermoplastics. However, the bonding between titanium wire and POM is not good, and they can move to each other, affecting the mechanical properties of the ligation clip. This application greatly enhances the adhesion between titanium wire and POM by forming grooves on the outer surface of the metal wire (preferably etched), forming a "rigid-flexible composite structure," breaking through the mechanical performance bottleneck of traditional single-material ligation clips, and improving their durability.

[0011] In one embodiment of the present invention, the V-shaped metal wire is a titanium wire with a diameter of 0.2 mm and a bending angle of about 80 degrees, which makes the bending modulus of the ligation clip reach more than 6 GPa, meeting the needs of most blood vessel clamping. In addition, the resilience of the titanium wire also inhibits the creep of the POM material.

[0012] In one embodiment of the present invention, the cross-section of the metal wire is rectangular, and at least one side of the metal wire has the groove; The metal wire has a first part, a connecting part, and a second part arranged sequentially. The first part corresponds to the first clamping arm, the connecting part corresponds to the elastic connecting part, and the second part corresponds to the second clamping arm.

[0013] The rectangular design of the metal wire not only prevents the metal wire and the ligation clip from rotating circumferentially, but also makes it easy to machine grooves on the side of the metal wire.

[0014] In one embodiment of the present invention, the elastic connecting portion has an arc-shaped opening, and the connecting portion of the metal wire avoids the arc-shaped opening; The locking hook has two first side surfaces and a middle surface located between the two first side surfaces. A guide surface is formed on the portion of the first side surface near the middle surface. The guide surface is an inclined surface or a curved surface. The first clamping arm has a first circular limiting post on the side near the locking hook. The latch includes a V-shaped notch at the end of the second clamping arm and second circular limiting posts on both sides of the end of the second clamping arm. The second circular limiting posts have triangular limiting parts. The two limiting parts are used to cooperate with the two guide surfaces of the latch hook respectively to limit the left and right positions of the latch hook, so that the latch hook can accurately cooperate with the V-shaped notch.

[0015] In one embodiment of the present invention, the junction of the guide surface and the intermediate surface is rounded to form a rounded portion. Traditional ligation clips do not have a rounded portion at the junction of the guide surface and the intermediate surface, resulting in poor sliding during the engagement of the hook and latch, and uneven tissue clamping. By rounding the junction of the guide surface and the intermediate surface, the frictional resistance when the hook slides through the V-shaped notch is reduced, thereby achieving fast and smooth sliding, better coordination with the clamping forceps, and significantly improving operational efficiency. Furthermore, this treatment effectively reduces stress concentration caused by pressure on the right-angled structure during sliding, prevents local deformation of the hook, eliminates sharp edges, and reduces the potential risk of injury to the user during use. Simultaneously, the rounded corner treatment also makes the ligation clip smoother and more aesthetically pleasing. This improvement effectively enhances the ease of use of the ligation clip.

[0016] In one embodiment of the present invention, the end of the limiting portion away from the second circular limiting post is rounded to form a rounded portion; The inner side of the limiting part is a straight surface for cooperating with the locking hook, and the outer side of the limiting part is an inclined surface. The further the inclined surface is from the second circular limiting post, the closer the inclined surface is to the straight surface. The angle between the inclined surface and the straight surface is 30°~40°.

[0017] Traditional ligation clips often have poorly designed limiting sections, which can lead to the latch springing open or falling off after closure, causing damage to surrounding tissue and affecting the clip's stability and durability. This application addresses this issue by chamfering the limiting section, transforming it from a sharp angle to a smooth transition, while also tilting the inclined surface inwards at 30°~40°. This improvement reduces resistance when the clip closes, enhancing operational smoothness, and the inward tilt increases stability in the locked state, reducing the risk of slippage due to external forces. Furthermore, the rounded corners reduce the sharp point at the top of the clip from scratching flesh and tissue during closure, contributing to a tighter lock and improving ligation reliability. The smooth transition of the latch and latch also reduces stress concentration in the material under stress, reducing the risk of fatigue fracture.

[0018] In one embodiment of the present invention, the connection between the second circular limiting post and the second clamping arm is rounded to form a rounded portion.

[0019] In use, the second circular limiting post is positioned in the positioning groove of the clamp. Significant stress concentration can easily occur between the second circular limiting post and the ligation clip body, potentially increasing the risk of breakage and resulting in poor clamping stability. This application improves the rigidity of the connection area by rounding the corners at the connection points between the two second circular limiting posts and the second clamping arm. This design effectively reduces stress concentration at the connection point, lowering the risk of breakage due to vascular tension. Specifically, the two triangular limiting parts and the second cylindrical limiting post are located at the upper end of the second clamping arm, acting as limiting elements to ensure that the upper and lower parts of the ligation clip do not experience longitudinal displacement. If the upper and lower parts of the ligation clip shift and slide apart, the ligation clip will lose its ligation function. Therefore, the two second circular limiting posts connected to the triangles need to maintain a more stable connection with the ligation clip body. The rounded corners effectively distribute force, ensuring that the ligation clip bears pressure evenly when clamping an object and when subjected to external forces that could cause it to slide apart, significantly enhancing its resistance to expansion and slippage. Furthermore, the rounded corner design reduces the accumulation of bacteria and dirt, facilitating sterilization during the production process. Overall, the rounded corner treatment here is an efficient structural optimization measure that improves the durability and stability of the ligation clip, as well as increases safety and ease of maintenance.

[0020] In one embodiment of the present invention, the first clamping arm has misaligned teeth on the side for clamping human tissue, and the second clamping arm has misaligned teeth on the side for clamping human tissue.

[0021] The staggered tooth design significantly improves the overall anti-slip performance of the ligation clip after it is closed, thereby enhancing the stability and durability of the object it holds.

[0022] In one embodiment of the present invention, preferably, the tooth tip of the tooth is offset toward the elastic connecting portion, and the tooth tip is rounded.

[0023] This design not only increases the contact area with the clamped tissue, enhancing friction, but also allows the inner angle of the tooth tips to provide a gentle slope during clamping, due to the lateral displacement from the tail (elastic connection side) to the head of the clamp. This makes it easier to clamp the blood vessel and position it in the appropriate area. Furthermore, the rounded corners of the tooth tips further reduce potential damage to the clamped object, avoiding direct insertion or cutting, and achieving fixation through friction. This comprehensive design improves the anti-slip effect of the ligation clip, enhancing the product's clamping stability and durability.

[0024] This application also discloses a method for manufacturing a ligation clip, used to manufacture the ligation clip described above, comprising the following steps: The material pretreatment step involves annealing the metal wire and then pickling it. The metal wire is made of titanium. The drawing process involves drawing the metal wire multiple times using a drawing die to obtain a metal wire of a set diameter. The rectangular metal wire forming process involves first changing the cross-section of the metal wire from a circle to an ellipse through a roller drawing process, and then changing the cross-section of the metal wire from an ellipse to a rectangle through another roller drawing process. The etching step involves using a chemical etching process to treat at least one sidewall of the metal wire, forming multiple grooves on the sidewall of the metal wire, the depth of which is 10~50μm. In the injection molding step, a ligation clip body is formed by injection molding on the outside of the metal wire to obtain a ligation clip, wherein the material of the ligation clip body is POM; The annealing step involves annealing the ligation clips.

[0025] In one embodiment of the present invention, the injection molding step is implemented by an injection molding device and a heatable injection mold. The injection molding device includes a screw conveyor mechanism, a material barrel is provided at the inlet of the screw conveyor mechanism, and a nozzle is provided at the outlet of the screw conveyor mechanism. The nozzle is used to inject molten POM material into the injection mold. The material barrel is divided into a first section, a second section, and a third section from top to bottom. During operation, the temperature of the first zone of the barrel is 170℃, the temperature of the second zone of the barrel is 180℃, the temperature of the third zone of the barrel is 195℃, the temperature of the nozzle is 195℃, the temperature of the injection mold is 80℃~100℃, the injection pressure of the nozzle is 20MPa, the injection time is 10s, the holding pressure of the nozzle is 10MPa, the holding time is 5s, and the cooling time is 30s.

[0026] Injection molding is a common molding technology in plastics processing due to its high precision, ease of operation, high quality, and wide range of applications. The quality of products produced by injection molding is far superior to that of blow molding and compression molding. Injection molding consists of four stages: plasticizing, filling, holding pressure, and cooling. Temperature, pressure, time, stress, and shrinkage all affect the quality of products produced by injection molding. First, in the plasticizing process, the barrel temperature has a significant impact on the flowability and plasticity of the plastic. The raw material melts in the barrel, and under high temperatures, it is prone to oxidation, ultimately affecting product performance. For example, the preparation of POM (Polymer Propane) thermosensitive plastic material requires strict control of heating temperature and time. It will severely decompose and turn yellow at 240℃, and the holding time at 210℃ should not exceed 20 minutes. During molding, while ensuring material flow, the lowest possible molding temperature and the shortest molding cycle should be used; solidification will occur at temperatures below approximately 160℃. Therefore, a gradient heating melting and plasticizing process is adopted. The temperature of the first zone of the barrel is 170℃ to prevent premature melting and screw slippage. The temperature of the second zone of the barrel is 180℃, which is the main melting zone to ensure that POM is fully plasticized. The temperature of the third zone of the barrel is 195℃ to avoid overheating and decomposition of the material.

[0027] Next is the control of the nozzle temperature, which directly affects the flowability and plasticity of the plastic bag. The nozzle temperature is set to 190℃, and should be slightly lower than the end of the barrel to prevent overflow. The mold has a shape corresponding to the clamping arms of the tie clamp. A heating method is used to control the mold temperature, which is set to 80~100℃. High-temperature molding can effectively reduce internal stress and improve melt filling and bonding strength. The titanium wire is positioned and fixed using positioning pins, which secure the titanium wire from both sides.

[0028] Next, the injection parameters are set, using an injection pressure of 20 MPa. Traditional pure POM material requires an injection pressure of 6 MPa, but to better incorporate the titanium wire during the flow of molten POM, the injection pressure is increased. The POM-titanium wire composite structure often also requires higher pressure. The holding pressure is 50%~70% of the injection pressure. Its function is to prevent backflow during cooling and reduce the shrinkage rate of the material during cooling; here, 10 MPa is selected as the holding pressure. The injection time is 10 seconds, the holding time is 5 seconds, and the cooling time is 30 seconds. Finally, the mold is opened and ejected. The ejection speed should be less than 10 mm / s to prevent whitening or deformation of the titanium wire. The molding cycle is 55~60 seconds.

[0029] During the filling stage, driven by the shear-thinning effect, the molten POM material penetrates into the microgroove structure on the surface of the titanium wire through capillary action, achieving interfacial bonding through a dual mechanism of van der Waals forces and mechanical anchoring. During the holding stage, the melt further compacts and fills the gaps in the microstructure. During the cooling and shrinkage process, the radial stress generated by the crystallization shrinkage of POM causes the polymer in the grooves to form a hook-shaped locking structure, achieving a synergistic strengthening effect of micro / nano-scale mechanical interlocking and molecular-level bonding.

[0030] In one embodiment of the present invention, in the injection molding step, the annealing temperature of the ligation clip is 100℃~120℃, and the annealing time is 30 minutes~60 minutes.

[0031] After injection molding is completed, the injection molded parts should be annealed first, with the temperature set at 100~120℃, which is lower than the melting point of POM 165℃. Then, the injection molded parts should be post-processed, such as removing flash and burrs, and checking for product quality problems such as insufficient plastic, flash, shrinkage, bubbles, black spots, weld lines, etc.

[0032] In one embodiment of the present invention, a specific implementation of the material pretreatment step is as follows: First, the titanium wire is pretreated in two steps. The first step is annealing, in which titanium wires with a diameter of 0.6 mm to 5.0 mm are annealed under vacuum or argon protection (temperature about 650 to 800°C, time 30 to 60 minutes) to eliminate the original stress and improve its plasticity. The second step is surface cleaning, which is done by pickling. The pickling solution is prepared using 10% HNO3 (nitric acid) + 2% HF (hydrofluoric acid) + the balance deionized water. It is suitable for removing the surface oxide layer of pure titanium (Gr1-Gr4) and Ti-6Al-4V alloy wire. The temperature is set to 20-40°C (room temperature to slight heating). Excessive temperature (>50°C) will accelerate the dissolution of titanium, resulting in a rough surface; excessive temperature (<15°C) will lead to insufficient reaction rate. The reaction time should be controlled within the range of 5-15 minutes, observing until the surface oxide layer is completely peeled off. Exceeding this time will result in excessive corrosion (a grayish surface). Mechanical stirring is used to enhance the fluidity of the acid solution, avoid uneven concentration in certain areas, and improve cleaning uniformity. The surface treatment effect is acceptable when the titanium wire surface is uniformly silvery-white. The surface treatment effect is unacceptable when there are localized graying, blackening, or iridescent oxide film residues.

[0033] In one embodiment of the present invention, a specific implementation of the drawing step is as follows: Objective: To gradually thin the thick titanium wire to a diameter close to the equivalent diameter of the target rectangular cross-section (approximately 0.226 mm, corresponding to a round wire of equal area).

[0034] One end of the titanium wire is ground into a tapered shape. Using a polycrystalline diamond (PCD) or cemented carbide die, the titanium wire is threaded into the die, with the shrinkage rate controlled at 10%~20% per pass (titanium has a high work hardening rate, so excessive deformation must be avoided). The initial diameter of the titanium wire is 0.6mm~5.0mm, and different drawing dies with different deformation amounts are selected according to the different sizes of titanium wire used. A high-temperature lubricant (graphite emulsion or molybdenum disulfide) is used to reduce friction. Specifically, a warm drawing process is employed, performed at 200~400°C (through induction heating or resistance heating) to improve the plasticity of the titanium wire and reduce the risk of cracking. The wire drawing speed is 4~6m / min. Annealing (vacuum / argon protection, temperature 600~750°C) is required after every 3~5 passes to eliminate work hardening.

[0035] In one embodiment of the present invention, a specific implementation of the rectangular metal wire forming step is as follows: Since the titanium wire has already been processed into a circular cross-section with an equivalent area in the previous step, the roll drawing process is divided into two passes. The first pass transforms the circle into an ellipse, and the second pass transforms the ellipse into a rectangle. The roll linear speed is 10~30 m / min, using 3 pairs of rolls made of high-hardness tool steel (SKD11) with a TiN surface coating to enhance wear resistance. A warm rolling process is employed, also using localized induction heating (200~300°C) to reduce the rheological stress of the titanium and improve its plasticity. An inert gas is introduced during this process to prevent oxidation. The final product is a rectangular cross-section with dimensions of 0.2 mm × 0.2 mm.

[0036] Chemical etching is used to treat the surface of titanium wires, specifically by etching a rectangular array of microgrooves on the wire surface to enhance the mechanical anchoring effect of POM (polyoxymethylene) melt wetting. Chemical etching is a mask etching technique that utilizes a chemical reaction principle. The etchant reacts chemically with the exposed workpiece between the mask and the workpiece, dissolving it and achieving material removal. Chemical etching is low-cost, highly efficient, can rapidly form surface microstructures, offers high precision, and eliminates processing stress, making it suitable for processing high-hardness materials.

[0037] In one embodiment of the present invention, a specific implementation of the etching step is as follows: A spray etching technique was used to process the surface of rectangular titanium wires. The etching solution consisted of hydrofluoric acid (HF) + nitric acid (HNO3), where HF dissolved the titanium metal and reacted to form a soluble [TiF6]²⁻ complex. HNO3 acted as an oxidant to inhibit excessive corrosion and improve etching uniformity. The spray pressure was 0.6~1 MPa. To achieve deep grooves, a solution of 10% HF + 30% HNO3 + 60% deionized water was used, which could etch grooves with depths of 10μm~50μm.

[0038] The mask is made using film, primarily composed of AgBr, with a resolution of 2-3 μm and a thickness of 4-6 μm. The titanium wire mask material is a self-drying photosensitive anti-corrosion ink, a UV-sensitive material. The mask material is then exposed to ultraviolet light; areas not covered by the film undergo photocuring, while unexposed areas are easily dissolved by alkaline substances. Next, the mask is developed by immersing it in a weakly alkaline solution (0.5%-1% Na2CO3 aqueous solution) for 1-3 minutes, followed by rinsing the workpiece with deionized water. The mask preparation is then complete. Etching is performed using a solution of 10% HF + 30% HNO3 + 60% deionized water for 5-8 minutes. The material is removed, ultimately forming a rectangular array of microgrooves with an etching width of 15-25 μm and a depth of 20-30 μm. This step completes the fabrication process.

[0039] In practical application, the ligation clip of this application cooperates with the clamping forceps. The clamping forceps drive the first clamp arm and the second clamp arm to move closer to each other and lock together. The clamping forceps have positioning grooves that are respectively connected to the first circular limiting post and the second circular limiting post.

[0040] In practical applications, the clamp can be a regular single-shot clamp or a burst-shot clamp.

[0041] The beneficial effects of this invention are as follows: The ligation clip of this application adopts a rigid-flexible composite mechanism, with a metal wire as the rigid core and a polymer material ligation clip body as the flexible matrix. In addition, the combination of grooves and anchoring parts effectively prevents the ligation clip body and the metal wire from moving relative to each other. The ligation clip of this application can achieve two major performances: First, the mechanical properties of rigidity and flexibility are synergistic. The metal wire provides the precise rigidity and stability required for surgery, while the ligation clip body absorbs the dynamic load during physiological activities, reducing the damage of the ligation clip to the tissue and giving it a wider clamping range. The synergy of the two makes the bending stiffness and elastic deformation capacity reach a balance. Second, it solves the problem of poor biocompatibility of metal materials. The polymer material is highly inert and has good tissue compatibility. The polymer material completely wraps the metal wire and comes into direct contact with human tissue, which can reduce the risk of rejection and inflammation. Attached Figure Description

[0042] Figure 1 This is a diagram of a ligation clip; Figure 2 This is a schematic diagram of the ligation clip from another angle; Figure 3 This is a schematic diagram showing the metal wire exposed after the ligation clip body is cut in half; Figure 4 yes Figure 3 A schematic diagram after the metal wire has been removed from the center; Figure 5 This is a schematic diagram of a metal wire; Figure 6This is a schematic diagram of the combination of the continuously firing clamp and the ligation clip; Figure 7 yes Figure 6 Enlarged view of point A in the middle; Figure 8 This is a schematic diagram of the combination of a single-shot clamp and a ligation clip. Figure 9 yes Figure 8 Enlarged view of point B in the middle.

[0043] The labels for the attached figures are as follows: 100. Ligation clip body; 100a. Rounded portion; 100b. Toothed portion; 100c. Receiving groove; 1. First clamping arm; 11. Locking hook; 111. First side surface; 112. Middle surface; 113. Guide surface; 12. First circular limiting post; 2. Second clamping arm; 21. Locking buckle; 211. V-shaped notch; 212. Second circular limiting post; 2121. Limiting part; 2121a. Flat surface; 2121b. Inclined surface; 3. Elastic connecting part; 31. Arc-shaped opening; 4. Applying clamp; 41. Positioning groove; 200. Metal wire; 201. First part; 202. Connecting part; 203. Second part; 200a. Groove. Detailed Implementation

[0044] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0045] In the description of this application, it should be noted that the terms "inner" and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product is in use. They are used only for the convenience of describing this application and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application. Furthermore, the terms "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0046] In the description of this application, it should also be noted that, unless otherwise expressly specified and limited, the terms "setup" and "connection" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0047] The present invention will now be described in detail with reference to the accompanying drawings.

[0048] like Figures 1-5 As shown, a ligation clip includes a V-shaped ligation clip body 100, which is made of polymer material. The ligation clip body 100 has a first clamping arm 1, a second clamping arm 2, and an elastic connecting part 3 connecting the first clamping arm 1 and the second clamping arm 2. The end of the first clamping arm 1 away from the elastic connecting part 3 has a locking hook 11, and the end of the second clamping arm 2 away from the elastic connecting part 3 has a locking buckle 21. When the first clamping arm 1 and the second clamping arm 2 are brought close together, the locking hook 11 and the locking buckle 21 cooperate to lock the clip. The clip also includes a metal wire 200 embedded in the first clamping arm 1, the second clamping arm 2, and the elastic connecting part 3. The outer surface of the metal wire 200 has multiple grooves 200a. The ligation clip body 100 is coated on the metal wire 200 by injection molding. The ligation clip body 100 has an anchoring part (not shown in the figure) extending into the grooves 200a.

[0049] The ligation clip of this application adopts a rigid-flexible composite mechanism, with the metal wire 200 as the rigid core and the ligation clip body 100 of polymer material as the flexible matrix. In addition, the combination of the groove 200a and the anchoring part effectively prevents the ligation clip body 100 and the metal wire 200 from moving relative to each other. The ligation clip of this application can achieve two major performances. First, the rigidity and flexibility of mechanical properties are coordinated. The metal wire 200 provides the precise rigidity and stability required for surgery, and the ligation clip body 100 absorbs the dynamic load in physiological activities, reducing the damage of the ligation clip to the tissue and giving it a wider clamping range. The two work together to balance the bending stiffness and elastic deformation capacity. Second, it solves the problem of poor biocompatibility of metal materials. The polymer material is highly inert and has good tissue compatibility. The polymer material completely wraps the metal wire 200 and comes into direct contact with human tissue, which can reduce the risk of rejection and inflammation.

[0050] In practical applications, the ligation clip body 100 has a receiving groove 100c for accommodating the metal wire 200, and the anchoring part is located on the side wall of the receiving groove 100c.

[0051] Preferably, the metal wire 200 is pure titanium wire (medical grade TA1), and the polymer material is high-grade polyoxymethylene (POM). POM material is ISO 10993 biocompatibility certified and has both high rigidity and low moisture absorption. POM has good mechanical properties, excellent creep resistance and stress relaxation ability, and its fatigue resistance is the highest among thermoplastics. However, the bonding between titanium wire and POM is not good, and they will move to each other, affecting the mechanical properties of the ligation clip. This application greatly enhances the adhesion between titanium wire and POM by forming a groove 200a on the outer surface of the metal wire 200 (preferably etched), forming a "rigid-flexible composite structure", breaking through the mechanical performance bottleneck of traditional single-material ligation clips and improving their durability.

[0052] In this embodiment, the V-shaped 200mm titanium wire has a diameter of 0.2mm and a bending angle of approximately 80 degrees, which allows the ligation clip to achieve a bending modulus of over 6GPa, meeting the needs of most blood vessel clamping. In addition, the resilience of the titanium wire also inhibits the creep of the POM material.

[0053] like Figure 5 As shown, in this embodiment, the cross-section of the metal wire 200 is rectangular, and at least one side of the metal wire 200 has a groove 200a. The metal wire 200 has a first part 201, a connecting part 202 and a second part 203 arranged in sequence. The first part 201 corresponds to the first clamping arm 1, the connecting part 202 corresponds to the elastic connecting part 3, and the second part 203 corresponds to the second clamping arm 2.

[0054] The rectangular design of the metal wire 200 not only prevents the metal wire 200 and the ligation clip body 100 from rotating circumferentially, but also makes it easy to process grooves 200a on the side of the metal wire 200.

[0055] like Figure 1 and Figure 2 As shown, in this embodiment, the elastic connecting part 3 has an arc-shaped opening 31, and the connecting part 202 of the metal wire 200 avoids the arc-shaped opening 31. The locking hook 11 has two first side surfaces 111 and a middle surface 112 located between the two first side surfaces 111. A guide surface 113 is formed on the part of the first side surface 111 near the middle surface 112. The guide surface 113 is an inclined surface or a curved surface. The first clamping arm 1 has a first circular limiting post 12 on the side near the locking hook 11. The latch 21 includes a V-shaped notch 211 located at the end of the second clamping arm 2 and second circular limiting posts 212 located on both sides of the end of the second clamping arm 2. The second circular limiting posts 212 have triangular limiting portions 2121. The two limiting portions 2121 are used to cooperate with the two guide surfaces 113 of the latch 11 respectively to limit the left and right positions of the latch 11, so that the latch 11 is precisely engaged with the V-shaped notch 211.

[0056] In this embodiment, the junction of the guide surface 113 and the intermediate surface 112 is rounded to form a rounded portion 100a. In traditional ligation clips, the junction of the guide surface 113 and the intermediate surface 112 does not have a rounded portion 100a, resulting in poor sliding between the locking hook 11 and the locking buckle 21, and uneven tissue clamping. By rounding the junction of the guide surface 113 and the intermediate surface 112, the frictional resistance of the locking hook 11 as it slides over the V-shaped notch 211 is reduced, enabling rapid and smooth sliding and better coordination with the clamping forceps 4, significantly improving operational efficiency. Furthermore, this treatment effectively reduces stress concentration caused by pressure on the right-angled structure during sliding, preventing local deformation of the locking hook 11, eliminating sharp edges, and reducing the potential risk of injury to the user during use. Simultaneously, the rounded corner treatment also makes the ligation clip smoother and more aesthetically pleasing. This improvement effectively enhances the ease of use of the ligation clip.

[0057] like Figure 1 and 2 As shown, in this embodiment, the end of the limiting part 2121 away from the second circular limiting post 212 is rounded to form a rounded part 100a; The inner surface of the limiting part 2121 is a flat surface 2121a for cooperating with the locking hook 11, and the outer surface of the limiting part 2121 is an inclined surface 2121b. The further the inclined surface 2121b is from the second circular limiting post 212, the closer the inclined surface 2121b is to the flat surface 2121a. The angle between the inclined surface 2121b and the flat surface 2121a is 30°~40°.

[0058] The design of the limiting part 2121 in traditional ligation clips is not entirely reasonable, which may lead to the locking buckle 21 popping out or falling off after closure, and causing damage to surrounding tissues, affecting the stability and durability of the ligation clip. In this application, the limiting part 2121 is chamfered, transforming it from a sharp angle design to a smooth transition, while the inclined surface 2121b is inclined inward at 30°~40°. This improvement reduces the resistance when the ligation clip closes, improving the smoothness of operation, and the inward inclined design increases the stability of the ligation clip in the locked state, reducing the risk of slippage due to external forces. Furthermore, the rounded corner treatment reduces the scratching of flesh and blood tissue by the original sharp point at the upper end of the ligation clip when closed. This improvement helps to achieve a tighter lock, thereby improving the reliability of ligation. The smooth transition of the locking hook 11 and locking buckle 21 also reduces stress concentration in the material under stress, which can lead to material fatigue fracture.

[0059] like Figure 1 and Figure 2 As shown, in this embodiment, the connection between the second circular limiting post 212 and the second clamping arm 2 is rounded to form a rounded portion 100a.

[0060] In use, the second circular limiting post 212 is positioned in the positioning groove 41 of the clamping clamp 4. Significant stress concentration can easily occur between the second circular limiting post 212 and the ligation clamp body 100, which may increase the risk of breakage during use, resulting in poor clamping stability. This application improves the rigidity of the connection area by rounding the corners at the connection points between the two second circular limiting posts 212 and the second clamping arm 2. This design effectively reduces stress concentration at the connection point and lowers the risk of breakage due to vascular tension. Specifically, the two triangular limiting parts 2121 and the second cylindrical limiting post are located at the upper end of the second clamping arm 2. They act as limiting elements, ensuring that the upper and lower parts of the ligation clamp do not experience longitudinal displacement. If the upper and lower parts of the ligation clamp shift and slide apart, the ligation clamp will lose its ligation function. Therefore, the two second circular limiting posts 212 connected to the triangles need to maintain a more stable connection with the ligation clamp body 100. Rounded corners effectively distribute force, ensuring the ligation clip bears pressure evenly when holding an object and subjected to external forces that could cause it to slip and separate, significantly enhancing its resistance to expansion and slippage. Furthermore, the rounded corner design reduces the accumulation of bacteria and dirt, facilitating sterilization during production. Overall, this rounded corner treatment is a highly efficient structural optimization measure that improves the durability and stability of the ligation clip, while also increasing safety and ease of maintenance.

[0061] like Figure 1 and 2 As shown, in this embodiment, the first clamping arm 1 has a staggered tooth 100b on the side used to clamp human tissue, and the second clamping arm 2 has a staggered tooth 100b on the side used to clamp human tissue.

[0062] The staggered teeth 100b design significantly improves the overall anti-slip performance of the ligation clip after closure, thereby enhancing the stability and durability of the clamped object.

[0063] In this embodiment, preferably, the tooth tip of the tooth portion 100b is biased toward the elastic connecting portion 3, and the tooth tip of the tooth portion 100b is rounded.

[0064] This design not only increases the contact area with the clamped tissue and enhances friction, but also allows the inner angle of the tooth tip of the 100b teeth to provide a gentle slope during clamping, due to the lateral displacement from the tail of the ligation clip (on the side of the elastic connection 3) towards the head. This makes it easier to clamp the blood vessel and position it in the appropriate area. Furthermore, the rounded corners of the tooth tips further reduce potential damage to the clamped object, avoiding direct insertion or cutting, and achieving fixation through friction. This comprehensive design improves the anti-slip effect of the ligation clip and enhances the product's clamping stability and durability.

[0065] like Figures 6-9 As shown, in practical application, the ligation clip of this application cooperates with the clamping forceps 4. The clamping forceps 4 drives the first clamping arm 1 and the second clamping arm 2 to move closer together and lock. The clamping forceps have positioning grooves 41 that are respectively positioned with the first circular limiting post 12 and the second circular limiting post 212. In practical application, the clamping forceps 4 can be a common single-shot clamping forceps 4 (see...). Figure 8 ), or it can be used as a clamp for rapid-fire 4 (see Figure 6 ).

[0066] This embodiment also discloses a method for manufacturing a ligation clip, used to manufacture the ligation clip of this embodiment, including the following steps: The material pretreatment steps involve annealing the metal wire and then pickling it. The metal wire is made of titanium. The drawing process involves drawing the metal wire multiple times using a drawing die to obtain a metal wire of a set diameter. The rectangular metal wire forming process involves first changing the cross-section of the metal wire from a circle to an ellipse through a roller drawing process, and then changing the cross-section of the metal wire from an ellipse to a rectangle through another roller drawing process. In the etching step, a chemical etching process is used to treat at least one sidewall of the metal wire, so that multiple grooves are formed on the sidewall of the metal wire, and the depth of the grooves is 10~50μm. In the injection molding step, the ligation clip body is formed by injection molding on the outside of the metal wire to obtain the ligation clip. The material of the ligation clip body is POM. The annealing step involves annealing the ligation clips.

[0067] In this embodiment, the injection molding step is carried out by injection molding equipment and a heatable injection mold. The injection molding equipment includes a screw conveyor mechanism, a barrel is provided at the feed port of the screw conveyor mechanism, and a nozzle is provided at the discharge port of the screw conveyor mechanism. The nozzle is used to inject molten POM material into the injection mold. The barrel is divided into barrel zone 1, barrel zone 2 and barrel zone 3 from top to bottom. During operation, the temperature of zone 1 of the barrel is 170℃, the temperature of zone 2 of the barrel is 180℃, the temperature of zone 3 of the barrel is 195℃, the temperature of the nozzle is 195℃, the temperature of the injection mold is 80℃~100℃, the injection pressure of the nozzle is 20Mpa, the injection time is 10s, the holding pressure of the nozzle is 10Mpa, the holding time is 5s, and the cooling time is 30s.

[0068] Injection molding is a common molding technology in plastics processing due to its high precision, ease of operation, high quality, and wide range of applications. The quality of products produced by injection molding is far superior to that of blow molding and compression molding. Injection molding consists of four stages: plasticizing, filling, holding pressure, and cooling. Temperature, pressure, time, stress, and shrinkage all affect the quality of products produced by injection molding. First, in the plasticizing process, the barrel temperature has a significant impact on the flowability and plasticity of the plastic. The raw material melts in the barrel, and under high temperatures, it is prone to oxidation, ultimately affecting product performance. For example, the preparation of POM (Polymer Propane) thermosensitive plastic material requires strict control of heating temperature and time. It will severely decompose and turn yellow at 240℃, and the holding time at 210℃ should not exceed 20 minutes. During molding, while ensuring material flow, the lowest possible molding temperature and the shortest molding cycle should be used; solidification will occur at temperatures below approximately 160℃. Therefore, a gradient heating melting and plasticizing process is adopted. The temperature of the first zone of the barrel is 170℃ to prevent premature melting and screw slippage. The temperature of the second zone of the barrel is 180℃, which is the main melting zone to ensure that POM is fully plasticized. The temperature of the third zone of the barrel is 195℃ to avoid overheating and decomposition of the material.

[0069] Next is the control of the nozzle temperature, which directly affects the flowability and plasticity of the plastic bag. The nozzle temperature is set to 190℃, and should be slightly lower than the end of the barrel to prevent overflow. The mold has a shape corresponding to the clamping arms of the tie clamp. A heating method is used to control the mold temperature, which is set to 80~100℃. High-temperature molding can effectively reduce internal stress and improve melt filling and bonding strength. The titanium wire is positioned and fixed using positioning pins, which secure the titanium wire from both sides.

[0070] Next, the injection parameters are set, using an injection pressure of 20 MPa. Traditional pure POM material requires an injection pressure of 6 MPa, but to better incorporate the titanium wire during the flow of molten POM, the injection pressure is increased. The POM-titanium wire composite structure often also requires higher pressure. The holding pressure is 50%~70% of the injection pressure. Its function is to prevent backflow during cooling and reduce the shrinkage rate of the material during cooling; here, 10 MPa is selected as the holding pressure. The injection time is 10 seconds, the holding time is 5 seconds, and the cooling time is 30 seconds. Finally, the mold is opened and ejected. The ejection speed should be less than 10 mm / s to prevent whitening or deformation of the titanium wire. The molding cycle is 55~60 seconds.

[0071] During the filling stage, driven by the shear-thinning effect, the molten POM material penetrates into the microgroove structure on the surface of the titanium wire through capillary action, achieving interfacial bonding through a dual mechanism of van der Waals forces and mechanical anchoring. During the holding stage, the melt further compacts and fills the gaps in the microstructure. During the cooling and shrinkage process, the radial stress generated by the crystallization shrinkage of POM causes the polymer in the grooves to form a hook-shaped locking structure, achieving a synergistic strengthening effect of micro / nano-scale mechanical interlocking and molecular-level bonding.

[0072] In this embodiment, during the injection molding step, the annealing temperature of the ligation clip is 100℃~120℃, and the annealing time is 30 minutes~60 minutes.

[0073] After injection molding is completed, the injection molded parts should be annealed first, with the temperature set at 100~120℃, which is lower than the melting point of POM 165℃. Then, the injection molded parts should be post-processed, such as removing flash and burrs, and checking for product quality problems such as insufficient plastic, flash, shrinkage, bubbles, black spots, weld lines, etc.

[0074] In this embodiment, a specific implementation of the material pretreatment step is as follows: First, the titanium wire is pretreated in two steps. The first step is annealing, in which titanium wires with a diameter of 0.6 mm to 5.0 mm are annealed under vacuum or argon protection (temperature about 650 to 800°C, time 30 to 60 minutes) to eliminate the original stress and improve its plasticity. The second step is surface cleaning, which is done by pickling. The pickling solution is prepared using 10% HNO3 (nitric acid) + 2% HF (hydrofluoric acid) + the balance deionized water. It is suitable for removing the surface oxide layer of pure titanium (Gr1-Gr4) and Ti-6Al-4V alloy wire. The temperature is set to 20-40°C (room temperature to slight heating). Excessive temperature (>50°C) will accelerate the dissolution of titanium, resulting in a rough surface; excessive temperature (<15°C) will lead to insufficient reaction rate. The reaction time should be controlled within the range of 5-15 minutes, observing until the surface oxide layer is completely peeled off. Exceeding this time will result in excessive corrosion (a grayish surface). Mechanical stirring is used to enhance the fluidity of the acid solution, avoid uneven concentration in certain areas, and improve cleaning uniformity. The surface treatment effect is acceptable when the titanium wire surface is uniformly silvery-white. The surface treatment effect is unacceptable when there are localized graying, blackening, or iridescent oxide film residues.

[0075] In this embodiment, one specific implementation of the pulling step is as follows: Objective: To gradually thin the thick titanium wire to a diameter close to the equivalent diameter of the target rectangular cross-section (approximately 0.226 mm, corresponding to a round wire of equal area).

[0076] One end of the titanium wire is ground into a tapered shape. Using a polycrystalline diamond (PCD) or cemented carbide die, the titanium wire is threaded into the die, with the shrinkage rate controlled at 10%~20% per pass (titanium has a high work hardening rate, so excessive deformation must be avoided). The initial diameter of the titanium wire is 0.6mm~5.0mm, and different drawing dies with different deformation amounts are selected according to the different sizes of titanium wire used. A high-temperature lubricant (graphite emulsion or molybdenum disulfide) is used to reduce friction. Specifically, a warm drawing process is employed, performed at 200~400°C (through induction heating or resistance heating) to improve the plasticity of the titanium wire and reduce the risk of cracking. The wire drawing speed is 4~6m / min. Annealing (vacuum / argon protection, temperature 600~750°C) is required after every 3~5 passes to eliminate work hardening.

[0077] In this embodiment, a specific implementation of the rectangular metal wire forming step is as follows: Since the titanium wire has already been processed into a circular cross-section with an equivalent area in the previous step, the roll drawing process is divided into two passes. The first pass transforms the circle into an ellipse, and the second pass transforms the ellipse into a rectangle. The roll linear speed is 10~30 m / min, using 3 pairs of rolls made of high-hardness tool steel (SKD11) with a TiN surface coating to enhance wear resistance. A warm rolling process is employed, also using localized induction heating (200~300°C) to reduce the rheological stress of the titanium and improve its plasticity. An inert gas is introduced during this process to prevent oxidation. The final product is a rectangular cross-section with dimensions of 0.2 mm × 0.2 mm.

[0078] Chemical etching is used to treat the surface of titanium wires, specifically by etching a rectangular array of microgrooves on the wire surface to enhance the mechanical anchoring effect of POM (polyoxymethylene) melt wetting. Chemical etching is a mask etching technique that utilizes a chemical reaction principle. The etchant reacts chemically with the exposed workpiece between the mask and the workpiece, dissolving it and achieving material removal. Chemical etching is low-cost, highly efficient, can rapidly form surface microstructures, offers high precision, and eliminates processing stress, making it suitable for processing high-hardness materials.

[0079] In this embodiment, one specific implementation of the etching step is as follows: A spray etching technique was used to process the surface of rectangular titanium wires. The etching solution consisted of hydrofluoric acid (HF) + nitric acid (HNO3), where HF dissolved the titanium metal and reacted to form a soluble [TiF6]²⁻ complex. HNO3 acted as an oxidant to inhibit excessive corrosion and improve etching uniformity. The spray pressure was 0.6~1 MPa. To achieve deep grooves, a solution of 10% HF + 30% HNO3 + 60% deionized water was used, which could etch grooves with depths of 10μm~50μm.

[0080] The mask is made using film, primarily composed of AgBr, with a resolution of 2-3 μm and a thickness of 4-6 μm. The titanium wire mask material is a self-drying photosensitive anti-corrosion ink, a UV-sensitive material. The mask material is then exposed to ultraviolet light; areas not covered by the film undergo photocuring, while unexposed areas are easily dissolved by alkaline substances. Next, the mask is developed by immersing it in a weakly alkaline solution (0.5%-1% Na2CO3 aqueous solution) for 1-3 minutes, followed by rinsing the workpiece with deionized water. The mask preparation is then complete. Etching is performed using a solution of 10% HF + 30% HNO3 + 60% deionized water for 5-8 minutes. The material is removed, ultimately forming a rectangular array of microgrooves with an etching width of 15-25 μm and a depth of 20-30 μm. This step completes the fabrication process.

[0081] The above description is merely a preferred embodiment of the present invention and does not limit the scope of patent protection of the present invention. Any equivalent structural transformations made based on the description and drawings of the present invention, whether directly or indirectly applied to other related technical fields, are similarly included within the scope of protection of the present invention.

Claims

1. A ligation clip, comprising a V-shaped ligation clip body, the ligation clip body being made of a polymer material, the ligation clip body having a first clamping arm, a second clamping arm, and an elastic connecting portion connecting the first clamping arm and the second clamping arm, wherein the end of the first clamping arm away from the elastic connecting portion has a locking hook, and the end of the second clamping arm away from the elastic connecting portion has a locking buckle, wherein when the first clamping arm and the second clamping arm are brought close together, the locking hook and the locking buckle cooperate to achieve locking; characterized in that, It also includes a metal wire built into the first clamp arm, the second clamp arm and the elastic connecting part. The outer surface of the metal wire has multiple grooves. The ligation clip body is covered on the metal wire by injection molding. The ligation clip body has an anchoring part that extends into the grooves.

2. The ligation clip as described in claim 1, characterized in that, The cross-section of the metal wire is rectangular, and at least one side of the metal wire has the groove. The metal wire has a first part, a connecting part and a second part arranged in sequence. The first part corresponds to the first clamping arm, the connecting part corresponds to the elastic connecting part, and the second part corresponds to the second clamping arm. The ligation clip body is made of POM, and the metal wire is made of titanium.

3. The ligation clip as described in claim 1, characterized in that, The elastic connecting part has an arc-shaped opening, and the connecting part of the metal wire avoids the arc-shaped opening; The locking hook has two first side surfaces and a middle surface located between the two first side surfaces. A guide surface is formed on the portion of the first side surface near the middle surface. The guide surface is an inclined surface or a curved surface. The first clamping arm has a first circular limiting post on the side near the locking hook. The latch includes a V-shaped notch at the end of the second clamping arm and second circular limiting posts on both sides of the end of the second clamping arm. The second circular limiting posts have triangular limiting parts. The two limiting parts are used to cooperate with the two guide surfaces of the latch hook respectively to limit the left and right positions of the latch hook, so that the latch hook can accurately cooperate with the V-shaped notch.

4. The ligation clip as described in claim 3, characterized in that, The junction between the guide surface and the intermediate surface is rounded to form a rounded portion.

5. The ligation clip as described in claim 3, characterized in that, The end of the limiting part away from the second circular limiting post is rounded to form a rounded part; The inner side of the limiting part is a straight surface for cooperating with the locking hook, and the outer side of the limiting part is an inclined surface. The further the inclined surface is from the second circular limiting post, the closer the inclined surface is to the straight surface. The angle between the inclined surface and the straight surface is 30°~40°.

6. The ligation clip as described in claim 3, characterized in that, The connection between the second circular limiting post and the second clamping arm is rounded to form a rounded part.

7. The ligation clip as described in claim 1, characterized in that, The first clamping arm has staggered teeth on one side for clamping human tissue, and the second clamping arm has staggered teeth on one side for clamping human tissue. The tips of the teeth are offset toward the elastic connection part, and the tips of the teeth are rounded.

8. A method for manufacturing a ligation clip, used to manufacture the ligation clip of claim 2, characterized in that, Includes the following steps: The material pretreatment step involves annealing the metal wire and then pickling it. The metal wire is made of titanium. The drawing process involves drawing the metal wire multiple times using a drawing die to obtain a metal wire of a set diameter. The rectangular metal wire forming process involves first changing the cross-section of the metal wire from a circle to an ellipse through a roller drawing process, and then changing the cross-section of the metal wire from an ellipse to a rectangle through another roller drawing process. The etching step involves using an etching process to treat at least one sidewall of the metal wire, forming multiple grooves on the sidewall of the metal wire, the depth of which is 10~50μm. In the injection molding step, a ligation clip body is formed by injection molding on the outside of the metal wire to obtain a ligation clip, wherein the material of the ligation clip body is POM; The annealing step involves annealing the ligation clips.

9. The method for manufacturing a ligation clip as described in claim 8, characterized in that, The injection molding step is carried out by injection molding equipment and a heatable injection mold. The injection molding equipment includes a screw conveyor mechanism, a material barrel is provided at the inlet of the screw conveyor mechanism, and a nozzle is provided at the outlet of the screw conveyor mechanism. The nozzle is used to inject molten POM material into the injection mold. The material barrel is divided into three sections from top to bottom: section one, section two, and section three. During operation, the temperature of the first zone of the barrel is 170℃, the temperature of the second zone of the barrel is 180℃, the temperature of the third zone of the barrel is 195℃, the temperature of the nozzle is 195℃, the temperature of the injection mold is 80℃~100℃, the injection pressure of the nozzle is 20MPa, the injection time is 10s, the holding pressure of the nozzle is 10MPa, the holding time is 5s, and the cooling time is 30s.

10. The method for manufacturing a ligation clip as described in claim 9, characterized in that, In the injection molding process, the annealing temperature of the ligation clip is 100℃~120℃, and the annealing time is 30 minutes~60 minutes.

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