A medical catheter preparation device and method

Abstract

The application discloses a medical catheter preparation device and method. An inner lining layer is covered on the outer surface of a mandrel, and an outer layer is covered on the outer surface of the inner lining layer to form a composite pipe body. A heat shrink tube is sleeved on the outer surface of the composite pipe body to obtain a to-be-rheological pipe body. A heating element II is arranged outside the to-be-rheological pipe body or the to-be-rheological pipe body is arranged in the heating element II. The heating element II is started to heat under a vacuum environment, the outer layer and the inner lining layer are fused, and a composite pipe is prepared. The heating of the heating element II is stopped, the mandrel and the composite pipe are cooled, the composite pipe is taken off from the mandrel after cooling, the heat shrink tube is removed, and a medical catheter is prepared. The heating element I can also be arranged on the mandrel. The heating element I and the heating element II are started to heat under the vacuum environment, the inner lining layer and the outer layer on the mandrel are fused, and the composite pipe is prepared. The mandrel is heated by the heating element I, the temperature of the most difficult heating position is rapidly increased, the risk of excessive heating aging of the outer layer material is reduced, and the generation of bubbles in the composite layer is avoided.

Description

Technical Field

[0001] This invention belongs to the field of medical device technology application, specifically relating to a medical catheter preparation device and method. Background Technology

[0002] To achieve special properties such as delivery and strong support, interventional catheters often utilize multi-layered composite structures. Currently, there are three main processing methods for medical multi-layered composite catheters: First, co-extrusion, where different materials are placed in different chambers of an extruder, melted at high temperatures, and then extruded in layers. Second, dip-coating, where a mandrel is passed through different liquid resin solutions, then the solvent is evaporated in a high-temperature furnace, cured, and the mandrel is removed to obtain the composite tubing. Third, catheter reflow welding, where the mandrel is passed through the catheter liner, and an inner liner layer, an outer layer, and heat-shrink tubing are successively fitted. At high temperatures, the inner and outer layers are molten, and under the shrinkage force of the heat-shrink tubing, the inner and outer layers bond together to form a composite tubing. The heat-shrink tubing restricts the movement of the plastic outer layer and is eventually peeled off from the outermost surface of the medical catheter using a peeling process. The mandrel is used for shaping the inner lumen of the medical catheter, preventing excessive deformation of the outer and inner layers due to the shrinkage force of the heat-shrink tubing. Finally, the medical catheter is removed from the mandrel.

[0003] In current reflow soldering processes for conduits, a heating lag occurs from the outer layer to the inner layer during the heating process. The inner layer temperature rises more slowly, and the inner layer lamination time is longer. When the mandrel is made of metal, its heat capacity is relatively large, requiring it to absorb more heat to raise its temperature. This necessitates an external heating device to provide even greater heat, exacerbating the heating lag. Extending the heating time or increasing the outer layer heating temperature may lead to overheating of the outer layer, causing material aging. Furthermore, air bubbles can exist between layers during lamination, affecting the lamination effect and consequently impacting the overall performance of the conduit. Summary of the Invention

[0004] To address the technical problems in existing catheters, such as air bubbles between layers during the inner layer bonding process and material aging caused by excessive heating of the outer layer due to prolonged fusion time, this invention provides a medical catheter preparation device and method.

[0005] The technical solution adopted is as follows:

[0006] On one hand, the present invention provides a medical catheter preparation device, including a mandrel, a vacuum chamber, and a heating element II disposed in the vacuum chamber or on the wall of the vacuum chamber; the heating element II is disposed outside the rheostat tube body or the rheostat tube body is placed in the heating element II, and the rheostat tube body is wrapped around the mandrel.

[0007] Preferably, the heating element II is a movable heating element sleeved on the outside of the rheostat tube body.

[0008] Furthermore, the heating element II is provided with a temperature measuring element. On the other hand, the present invention also provides a method for preparing a medical catheter using a medical catheter preparation device, wherein an inner liner is covered on the outer surface of a mandrel, and an outer layer is covered on the outer surface of the inner liner to form a composite tube; a heat-shrink tubing is fitted onto the outer surface of the composite tube to obtain a rheostat tube body; a heating element II is placed outside the rheostat tube body or the rheostat tube body is placed inside the heating element II and placed in a vacuum environment in a vacuum chamber; the heating element II is activated to heat the tube, causing the outer layer and the inner liner to fuse together to obtain the composite tube; the heating element II is stopped to allow the composite tube to cool; after the composite tube has cooled, it is removed from the mandrel, and the heat-shrink tubing is removed to obtain the medical catheter.

[0009] Preferably, the inner lining and outer layer are tubular, and the inner lining and outer layer are fitted onto the mandrel to form a composite tube; or the inner lining and outer layer are both sheets, which are wound sequentially onto the mandrel to form a composite tube; or the inner lining and outer layer simultaneously include tubular and sheet materials, which are disposed on the mandrel to form a composite tube.

[0010] Furthermore, an intermediate layer is provided between the inner liner and the outer layer; the intermediate layer is a polymer tubing or a metal tubing, and the intermediate layer has an engraved structure or a hollow structure; or the intermediate layer is woven or wound with metal wires and / or polymer wires on the inner liner. On the other hand, the present invention also provides another medical catheter preparation device, comprising: a heating element I, a heating element II, a mandrel, and a vacuum chamber, wherein the heating element II is disposed within the vacuum chamber or on the wall of the vacuum chamber; the heating element II is disposed outside the rheostat tube body to be rheostated or the rheostat tube body to be rheostated is placed in the heating element II, the rheostat tube body to be rheostated is wrapped around the mandrel, and the heating element I is arranged on the mandrel.

[0011] Preferably, the mandrel is heated by conduction, the mandrel has a cavity structure, and the heating element I is disposed inside the cavity of the mandrel.

[0012] Preferably, the mandrel is a metal structure and serves as the heating element I.

[0013] Preferably, the mandrel is heated by induction, and an electromagnetic induction coil is provided outside the mandrel. The mandrel and the rheostat body are located in the cavity formed by the electromagnetic induction coil. The current applied to the electromagnetic induction coil generates an induced current in the mandrel to heat the mandrel.

[0014] Preferably, the heating element II is a movable heating element sleeved on the outside of the rheostat tube body.

[0015] Furthermore, both heating element I and heating element II are equipped with temperature sensing elements.

[0016] On the other hand, the present invention also provides a method for preparing a medical catheter using a medical catheter preparation device, wherein a heating element I is arranged on a mandrel; an inner liner is covered on the outer surface of the mandrel, and an outer layer is covered on the outer surface of the inner liner to form a composite tube; a heat shrink tubing is fitted on the outer surface of the composite tube to obtain a rheometry tube body; a heating element II is placed outside the rheometry tube body or the rheometry tube body is placed in the heating element II and placed in a vacuum environment in a vacuum chamber; heating elements I and II are started to heat, so that the outer layer and the inner liner are fused to obtain a composite tube; heating elements I and II are stopped to allow the mandrel and composite tube to cool; after the composite tube has cooled, it is removed from the mandrel, and the heat shrink tubing is removed to obtain a medical catheter.

[0017] Preferably, in a vacuum environment, heating element I is activated simultaneously to heat the mandrel and heating element II is activated simultaneously to heat the outer layer.

[0018] Preferably, heating element I is activated first to heat the mandrel. Once the mandrel temperature reaches the preset temperature, heating element II is activated in a vacuum environment to heat the outer layer.

[0019] Preferably, the inner lining and outer layer are tubular, and the inner lining and outer layer are fitted onto the mandrel to form a composite tube; or the inner lining and outer layer are both sheets, which are wound sequentially onto the mandrel to form a composite tube; or the inner lining and outer layer simultaneously include tubular and sheet materials, which are disposed on the mandrel to form a composite tube.

[0020] Furthermore, an intermediate layer is provided between the inner lining layer and the outer layer; the intermediate layer is a polymer tubing or a metal tubing, and the intermediate layer has an engraved structure or a hollow structure; or the intermediate layer is woven or wound onto the inner lining layer by metal wires and / or polymer wires. The technical solution of this invention has the following advantages:

[0021] A. The medical catheter preparation apparatus provided by the present invention, in the preparation of medical catheters, obtains a composite tube body by sequentially mounting an inner liner and an outer layer on a mandrel, and then obtains a rheostat tube body by mounting a heat shrink tubing on the outside of the composite tube body. Then, a heating element II is placed outside the rheostat tube body or the rheostat tube body is placed in the heating element II, and the rheostat tube body is heated in a vacuum environment of a vacuum chamber to achieve complete fusion of the inner liner and the outer layer, avoids the generation of air bubbles in the fusion layer between the inner liner and the outer layer, improves the quality and rate of fusion, and significantly improves the yield of medical catheters.

[0022] B. The medical catheter preparation apparatus provided by this invention, in the preparation of medical catheters, has a heating element I arranged on the mandrel, and then an inner liner and an outer layer are sequentially covered on the mandrel to form a composite tube. In the vacuum environment of the vacuum chamber, the heating elements I and II are activated for heating treatment, so that the inner liner and the outer layer reach the fusion temperature simultaneously and form a whole, thus obtaining the composite tube. This invention heats the mandrel by heating element I, so that the temperature of the position that is most difficult to heat up by the external heating element can be rapidly increased, without having to increase the heating time or the heating temperature of the outer layer, thus reducing the risk of excessive heat aging of the outer layer material.

[0023] C. This invention uses a mandrel heating method to fuse the inner and outer layers of the conduit. The fusion between the inner and outer layers is uniform. The increase in mandrel temperature causes the temperature of the inner layer to rise rapidly. On the one hand, this helps to melt the outer layer faster together with the heating element II. On the other hand, it ensures that the temperature between the outer surface of the inner layer and the inner surface of the outer layer can be maintained quickly, which improves the fusion effect of the inner layer. The bonding strength between the inner and outer layers can be effectively improved, and the fusion time is also shortened. Attached Figure Description

[0024] To more clearly illustrate the specific embodiments of the present invention, the accompanying drawings used in the specific embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0025] Figure 1 This is a flowchart of the medical catheter preparation method provided by the present invention;

[0026] Figure 2 This is a schematic diagram of the structure of a medical catheter according to an embodiment of the present invention;

[0027] Figure 3 It shows Figure 1 Cross-sectional view along line AA;

[0028] Figure 4 This is a schematic diagram of the structure of a medical catheter preparation device according to an embodiment of the present invention;

[0029] Figure 5 This is a flowchart of a medical catheter preparation method according to another embodiment of the present invention;

[0030] Figure 6 This is a schematic diagram of the structure of a medical catheter preparation device according to another embodiment of the present invention.

[0031] The meanings of the symbols in the image are as follows:

[0032] 10-Medical catheter, 12-Catheter body, 13-Inner liner, 14-Outer layer, 15-Intermediate layer, 20-Medical catheter preparation device, 21-Vacuum chamber, 22-Fixing element, 23-Mandrel, 24-Heating element II, 25-Heating element I, 26-Rheology tube body to be modified, 27-Guide rail. Detailed Implementation

[0033] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0034] like Figure 2 and Figure 3 As shown, the present invention provides a medical catheter 10, wherein the catheter includes an elongated catheter body 12 having a distal end, a proximal end, and a central chamber. The catheter body includes an inner liner 13 and an outer layer 14, both of which can be made of a suitable polymer material. For example, the material of the inner liner 13 can be any one or a combination of multiples of polytetrafluoroethylene, polyolefin, polyether block polyamide, and polyurethane. The material of the outer layer 14 can be at least one of polyamide, Pebax, polyurethane, and polyolefin.

[0035] like Figure 4 The diagram shows a schematic of the structure of a medical catheter preparation device 20 according to a specific embodiment of the present invention. The device 20 includes a mandrel 23 and a vacuum chamber 21. A heating element II 24 can be provided inside the vacuum chamber 21 or on the wall of the vacuum chamber 21. The heating element II 24 can be provided outside the rheostat tube body 26, or the rheostat tube body 26 can be placed in the heating element II 24, and the rheostat tube body 26 is wrapped around the mandrel 23.

[0036] A fixing element 22 is provided inside the vacuum chamber 21, and the end of the mandrel 23 can be fixed to the fixing element 22. The mandrel 23 can be fixed at both ends, or at one end only, and the other end can be left unfixed. The mandrel 23 can be fixed by suspending it on the fixing element, inserting it into the fixing element, or by other suitable methods. Figure 4In one embodiment shown, both ends of the mandrel 23 are fixed. The rheostat tube 26 is disposed on the outer surface of the mandrel 23, and a heating element II 24 is sleeved on the outside of the rheostat tube 26. A guide rail 27 is also provided inside the vacuum chamber 21, and the heating element II 24 is disposed on the guide rail 27 and can move up and down along the guide rail 27. When the heating element II 24 moves up and down along the guide rail 27, it can heat the rheostat tube 26. A temperature sensing element may also be provided on the heating element II 24, and the temperature sensing element can be any suitable element, such as a temperature sensor. Figure 1 As shown, the specific method includes the following steps:

[0037] [S01] The inner liner 13 is placed over the outer surface of the mandrel 23, and the outer layer 14 is placed over the outer surface of the inner liner 13 to form a composite tube. If both the inner liner 13 and the outer layer 14 are tubular structures, the inner diameter of the inner liner 13 is larger than the outer diameter of the mandrel 23, which facilitates the insertion of the mandrel 23 into the cavity of the inner liner 13, and then the outer layer 14 is fitted onto the inner liner 13 to obtain the composite tube. The inner liner 13 used in this invention is preferably a PTFE tube, whose outer surface is etched to facilitate fusion with the outer layer 14. At the same time, the inner surface of the inner liner 13 has lubricating properties to facilitate the removal of the mandrel.

[0038]

S02

[0039]

S03

[0040] The heating element II can be directly mounted on the wall of the vacuum chamber. The heating element II can also be any suitable movable heating element, such as a ring, which can be moved back and forth to heat the rheostat body. In this case, the rheostat body, the mandrel and the heating element II need to be placed together in the vacuum chamber.

[0041] Heating in a vacuum environment within a vacuum chamber can prevent the formation of air bubbles between the inner and outer lining layers, improving the quality and rate of fusion and significantly increasing the yield of medical catheters.

[0042] As the temperature rises, the inner diameter of the heat shrink tubing shrinks, and the outer layer melts. Under the clamping pressure of the heat shrink tubing, the outer and inner layers fuse together to form a composite tubing.

[0043]

S04

[0044] After the heat treatment is completed, the heating element II24 is turned off, and the composite tube on the mandrel 23 is cooled.

[0045]

S05

[0046] Figure 6 This is a schematic diagram of the structure of a medical catheter preparation device 20 according to another embodiment of the present invention, specifically including: heating element I 25, heating element II 24, mandrel 23 and vacuum chamber 21. Heating element II 24 can be disposed inside the vacuum chamber 21 or on the wall of the vacuum chamber. Heating element II can be disposed outside the rheostat tube body to be modified, or the rheostat tube body to be modified can be placed in the heating element II. The rheostat tube body to be modified is wrapped around the mandrel 23. Heating element I is arranged on the mandrel 23.

[0047] according to Figure 6 In the specific embodiment shown, the heating element II 24 is disposed on the wall of the vacuum chamber. The mandrel 23 can be a cavity structure, and the heating element I 25 can be disposed inside the cavity of the mandrel 23. Heating in a vacuum environment can be achieved by directly placing the rheostat body 26 and the mandrel 23 together into the vacuum chamber 21. Temperature sensing elements can also be provided on the heating element I and heating element II; these temperature sensing elements can be any suitable element, such as a temperature sensor.

[0048] Figure 5 The illustration shows a method for preparing a medical catheter according to another embodiment of the present invention, such as... Figure 5 As shown, the specific methods include:

[0049]

S01

[0050] The mandrel 23 is equipped with a heating element I25. The mandrel 23 can be heated in the following ways: The mandrel 23 can be heated by conduction, for example, if the mandrel 23 has a hollow structure, the heating element I is disposed within the cavity of the mandrel 23. In this case, the heating element I25 can be a resistance wire or other suitable element. The mandrel 23 can also be heated by induction. The mandrel itself is a metal structure, and an electromagnetic induction coil is disposed outside the mandrel. The mandrel 23 and the rheostat body 26 are located within the cavity of the electromagnetic induction coil. Therefore, the current applied to the electromagnetic induction coil will generate an induced current in the metal body of the mandrel 23, thereby heating the mandrel 23. Alternatively, the mandrel 23 is a metal structure, and it itself can serve as the heating element I. In this case, the heating element I25 can be a resistance wire or other suitable element.

[0051]

S02

[0052]

S03

[0053]

S04

[0054] The heating process can be completed entirely in a vacuum. That is, heating elements I25 and II24 are activated simultaneously in a vacuum environment to fuse the inner and outer lining layers on the mandrel, thus forming a composite tube. Alternatively, heating element I25 can be activated first to heat the mandrel. When the mandrel reaches a preset temperature, heating element II24 is activated in a vacuum environment to fuse the inner and outer lining layers on the mandrel, thus forming a composite tube.

[0055] Heating the mandrel rapidly raises the temperature of the area where heating element II24 was previously most difficult to heat up, without needing to increase heating time or the outer layer temperature, thus reducing the risk of excessive heat aging of the outer layer material. The increased mandrel temperature also rapidly raises the temperature of a crucial part of the composite layer—the inner liner. This helps the outer layer melt more quickly, working in conjunction with the external heating element II24, and ensures that the temperature of the most critical section of the composite layer—the area between the outer side of the inner liner and the inner side of the outer layer—is maintained quickly. Simultaneously, heating in a vacuum environment prevents the formation of air bubbles between the inner and outer layers, improving the quality and rate of fusion and significantly increasing the yield of medical catheters.

[0056] As the temperature rises, the inner diameter of the heat shrink tubing shrinks, and the outer layer melts. Under the clamping pressure of the heat shrink tubing, the outer and inner layers fuse together to form a composite tubing.

[0057]

S05

[0058] After heat treatment is completed, heating elements I25 and II24 are turned off, while mandrel 23 and composite tube are cooled.

[0059]

S06

[0060] This invention employs a mandrel heating method to fuse the inner liner 13 and outer layer 14 of a medical catheter. This results in a uniform fusion between the inner liner 13 and outer layer 14, improving the fusion effect of the inner liner 13 and effectively enhancing the bond strength between them, while also shortening the fusion time. Specifically, the mandrel heating allows for rapid heating of the inner liner 13, starting from its inner surface. Therefore, throughout the heating process, the heating of the outer layer 14 and the mandrel heating occur simultaneously, ensuring the crucial melting of the outer layer and the temperature rise between the outer and inner walls of the inner liner during the fusion process, thus improving the quality and speed of the fusion.

[0061] The inner liner 13 and outer layer 14 can be tubular, sheet-like, or a combination of both. When the inner liner 13 and outer layer 14 are tubular, they can be sequentially fitted onto the mandrel to form a composite tube. When both the inner liner 13 and outer layer 14 are sheets, they can be sequentially wound around the mandrel to form a composite tube. Heating elements I and II are activated to heat and fuse the composite tube to form a composite tube. When the inner liner 13 and outer layer 14 can simultaneously comprise tubular and sheet-like structures, the inner liner 13 can be tubular and the outer layer 14 can be sheet-like, or the inner liner 13 can be sheet-like and the outer layer 14 can be tubular, or other suitable combinations thereof, forming a composite tube by being mounted on the mandrel 23.

[0062] As a further preferred embodiment of the present invention, such as Figure 3 As shown, an intermediate layer 15 may also be provided between the inner lining layer 13 and the outer layer 14. The intermediate layer 15 may be a pipe, such as a polymer pipe or a metal pipe, with an engraved or hollowed-out structure on the pipe wall. It may also be made of metal wire or polymer wire, or a combination of metal wire and polymer wire, woven or wound on the inner lining layer.

[0063] The method for preparing medical catheters provided by this invention can improve the bonding effect of the inner liner, make the inner liner and outer layer bonded uniformly, shorten the fusion time, and also avoid the phenomenon of air bubbles between layers.

[0064] Any aspects not covered in this invention are applicable to existing technologies.

[0065] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A method for preparing a medical catheter using a medical catheter preparation device, characterized in that, The medical catheter fabrication apparatus includes: a mandrel, a vacuum chamber, and a heating element II disposed within or on the wall of the vacuum chamber; the heating element II is disposed outside the rheostat tube body to be modified, or the rheostat tube body to be modified is placed inside the heating element II, with the rheostat tube body wrapped around the mandrel. The specific method is as follows: The inner lining layer is placed over the outer surface of the mandrel, and the outer layer is placed over the outer surface of the inner lining layer to form a composite tube. Heat shrink tubing is fitted onto the outer surface of the composite tube to obtain the rheology tube body; The heating element II is placed outside the rheostat tube body or the rheostat tube body is placed inside the heating element II and placed in the vacuum environment of the vacuum chamber. The heating element II is then activated to heat the tube, so that the outer layer and the inner lining layer are fused together to form a composite tube. Stop heating element II to allow the composite tube to cool down; After the composite tube cools down, it is removed from the mandrel, and the heat shrink tubing is removed to obtain the medical catheter.

2. The method for preparing a medical catheter according to claim 1, characterized in that, The heating element II is a movable heating element that is sleeved on the outside of the rheostat tube body.

3. The method for preparing a medical catheter according to claim 1, characterized in that, The heating element II is equipped with a temperature measuring element.

4. The method for preparing a medical catheter according to claim 1, characterized in that, The inner lining and outer layer are tubular, and the inner lining and outer layer are fitted onto the mandrel to form a composite tube; or the inner lining and outer layer are both sheets, which are wound sequentially onto the mandrel to form a composite tube; or the inner lining and outer layer include both tubular and sheet materials, which are disposed on the mandrel to form a composite tube.

5. The method for preparing a medical catheter according to claim 4, characterized in that, An intermediate layer is provided between the inner lining layer and the outer layer; the intermediate layer is a polymer tube or a metal tube, and the intermediate layer has an engraved structure or a hollow structure; or the intermediate layer is woven or wound on the inner lining layer by metal wires and / or polymer wires.

6. A method for preparing a medical catheter using a medical catheter preparation device, characterized in that, The medical catheter fabrication apparatus includes: a heating element I, a heating element II, a mandrel, and a vacuum chamber. The heating element II is disposed within the vacuum chamber or on the wall of the vacuum chamber. The heating element II is located outside the rheostat tube body to be modified, or the rheostat tube body to be modified is placed inside the heating element II. The rheostat tube body is wrapped around the mandrel. The heating element I is arranged on the mandrel. The specific fabrication method is as follows: Heating element I is arranged on the spindle; The inner lining layer is placed over the outer surface of the mandrel, and the outer layer is placed over the outer surface of the inner lining layer to form a composite tube. Heat shrink tubing is fitted onto the outer surface of the composite tube to obtain the rheology tube body; The heating element II is placed outside the rheostat tube body or the rheostat tube body is placed inside the heating element II and placed in the vacuum environment of the vacuum chamber. The heating elements I and II are started to heat, so that the outer layer and the inner lining layer are fused together to obtain a composite tube. Stop heating elements I and II to allow the mandrel and composite tube to cool down; After the composite tube cools down, it is removed from the mandrel, and the heat shrink tubing is removed to obtain the medical catheter.

7. The method for preparing a medical catheter according to claim 6, characterized in that, The mandrel is heated by conduction. The mandrel has a hollow structure, and the heating element I is disposed inside the cavity of the mandrel.

8. The method for preparing a medical catheter according to claim 6, characterized in that, The mandrel is a metal structure and it itself serves as heating element I.

9. The method for preparing a medical catheter according to claim 6, characterized in that, The mandrel is heated by induction, and an electromagnetic induction coil is provided outside the mandrel. The mandrel and the rheostat body are located in the cavity formed by the electromagnetic induction coil. The current applied to the electromagnetic induction coil generates an induced current in the mandrel, which heats the mandrel.

10. The method for preparing a medical catheter according to claim 6, characterized in that, The heating element II is a movable heating element that is sleeved on the outside of the rheostat tube body.

11. The method for preparing a medical catheter according to claim 10, characterized in that, Both heating element I and heating element II are equipped with temperature measuring elements.

12. The method for preparing a medical catheter according to claim 11, characterized in that, In a vacuum environment, heating element I is activated simultaneously to heat the mandrel, and heating element II is activated simultaneously to heat the outer layer.

13. The method for preparing a medical catheter according to claim 12, characterized in that, First, start heating element I to heat the mandrel. Once the mandrel reaches the preset temperature, start heating element II to heat the outer layer in a vacuum environment.

14. The method for preparing a medical catheter according to claim 13, characterized in that, The inner lining and outer layer are tubular, and the inner lining and outer layer are fitted onto the mandrel to form a composite tube; or the inner lining and outer layer are both sheets, which are wound sequentially onto the mandrel to form a composite tube; or the inner lining and outer layer include both tubular and sheet materials, which are disposed on the mandrel to form a composite tube.

15. The method for preparing a medical catheter according to any one of claims 6-14, characterized in that, An intermediate layer is provided between the inner lining layer and the outer layer; the intermediate layer is a polymer tube or a metal tube, and the intermediate layer has an engraved structure or a hollow structure; or the intermediate layer is woven or wound on the inner lining layer by metal wires and / or polymer wires.

Images