Electrocoagulation guidewire-based insulation structure and method of forming same, and electrocoagulation guidewire

Abstract

The application provides an insulation structure based on an electrocoagulation guide wire, a forming method thereof, and the electrocoagulation guide wire. The forming method of the insulation structure based on the electrocoagulation guide wire comprises the following steps: performing one-time heat-shrinking and flattening treatment on the PET heat-shrinking tube, so that the PET heat-shrinking tube is sequentially heat-shrunk along the direction from the distal end of the alloy core wire to the proximal end, and the TPU leaching layer overlapped by the PET heat-shrinking tube is softened and extruded and deformed in the PET heat-shrinking tube towards the proximal end of the alloy core wire; performing tearable heat-shrinking and flattening treatment on the TPU leaching layer, so that the TPU leaching layer is sleeved with a tearable heat-shrinking tube, and the tearable heat-shrinking tube is at least partially heat-shrunk and sleeved at the distal end of the PET heat-shrinking tube, and the TPU leaching layer is softened and extruded and deformed in the tearable heat-shrinking tube. The forming method of the insulation structure based on the electrocoagulation guide wire can improve the uniformity of the thickness of the insulation sheath.

Description

Technical Field

[0001] This invention relates to the field of molding technology for plastic materials used in medical devices, and in particular to an insulating structure based on an electrocoagulation wire, a molding method thereof, and the electrocoagulation wire. Background Technology

[0002] This section provides only background information relevant to this disclosure and is not necessarily prior art.

[0003] Electrocoagulation guidewires are mainly composed of core wires, insulating sheaths, and functional coatings. For the insulating sheath, if there are thickness differences, it will significantly reduce the insulation performance and increase clinical risks. In particular, the requirements for the uniformity of the thickness of the insulating sheath are most stringent for high-precision surgical scenarios such as neurointervention and cardiac ablation.

[0004] To improve the consistency of the wire diameter in electrocoagulation conductors, the distal end of the core wire is impregnated with TPU to form an insulating sheath, while the proximal end is heat-shrinked with PET heat-shrink tubing to form an insulating sheath. The TPU-impregnated and PET heat-shrink tubing insulating sheaths need to overlap to ensure the overall insulation of the core wire. However, this overlap causes a localized increase in the thickness of the insulating sheath, such as... Figure 1 As shown, this leads to an imbalance in the electric field distribution, increasing clinical risks. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide an insulation structure based on electrocoagulation wire, a molding method thereof, and an electrocoagulation wire that can improve the thickness uniformity of the insulation structure.

[0006] The objective of this invention is achieved through the following technical solution:

[0007] A method for forming an insulation structure based on an electrocoagulating wire includes the following steps:

[0008] Obtain alloy core wire;

[0009] The alloy core wire is subjected to an extraction treatment to form a TPU extraction layer at the distal end of the alloy core wire.

[0010] The alloy core wire after the extraction treatment is positioned so that a PET heat shrink tube is sleeved on the proximal end of the alloy core wire, and the PET heat shrink tube partially overlaps the proximal end of the TPU extraction layer.

[0011] The PET heat shrink tubing is subjected to a heat shrinking and leveling process to sequentially heat shrink the PET heat shrink tubing from the far end to the near end along the direction of the alloy core wire, and the TPU impregnation layer overlapped by the PET heat shrink tubing is softened and extruded and deformed in the PET heat shrink tubing towards the near end of the alloy core wire.

[0012] The TPU impregnation layer is subjected to a tearable heat shrink leveling treatment so that a tearable heat shrink tube is sleeved on the TPU impregnation layer, and the tearable heat shrink tube is at least partially heat-shrinked and sleeved on the far end of the PET heat shrink tube. The TPU impregnation layer is softened and squeezed and deformed inside the tearable heat shrink tube.

[0013] In one embodiment, the overlap length of the PET heat shrink tubing on the TPU impregnation layer is 2mm to 5mm.

[0014] In one embodiment, the thickness of the TPU impregnation layer is 0.02 mm to 0.04 mm.

[0015] In one embodiment, the thickness of the PET heat shrink tubing is 0.01 mm to 0.05 mm.

[0016] In one embodiment, the outer diameter of the overlap between the PET heat shrink tubing and the TPU impregnation layer is the same as the outer diameter of the proximal end of the TPU impregnation layer.

[0017] In one embodiment, the outer diameter of the distal end of the alloy core wire is smaller than the outer diameter of the proximal end of the alloy core wire.

[0018] In one embodiment, the outer diameter of the distal end of the alloy core wire gradually increases in the direction from the distal end to the proximal end.

[0019] In one embodiment, the outer diameter of the distal end of the alloy core wire is 0.08 mm to 0.36 mm.

[0020] In one embodiment, the distal end of the alloy core wire is a nickel-titanium alloy core wire.

[0021] In one embodiment, the proximal end of the alloy core wire is a stainless steel alloy core wire.

[0022] In one embodiment, at the junction of the proximal and distal ends of the alloy core wire, the outer diameter of the proximal end of the alloy core wire is the same as the outer diameter of the distal end of the alloy core wire, and the PET is at least partially sleeved at the junction of the proximal and distal ends of the alloy core wire.

[0023] In one embodiment, the tearable heat shrink tubing is FEP heat shrink tubing.

[0024] In one embodiment, the PET heat shrink tubing undergoes a heat shrinking and leveling process, the specific steps of which are as follows:

[0025] The distal end of the PET heat shrink tubing is subjected to heat shrinking treatment so that the distal end of the PET heat shrink tubing is sequentially heat-shrinked along the distal end of the alloy core wire toward the proximal end, and the TPU impregnation layer overlapped by the PET heat shrink tubing is softened and extruded and deformed in the PET heat shrink tubing toward the proximal end of the alloy core wire.

[0026] The proximal end of the PET heat shrink tubing is subjected to a two-stage heat shrinking process, so that the proximal end of the PET heat shrink tubing is sequentially heat-shrinked along the direction from the distal end of the alloy core wire toward the proximal end.

[0027] In one embodiment, the distal end of the PET heat shrink tubing is heat-shrinked at a temperature of T1.

[0028] At a temperature of T2, the proximal end of the PET heat shrink tubing is subjected to a two-stage heat shrinking process.

[0029] Where T1 > T2, and T2 ≥ 100℃.

[0030] In one embodiment, the temperature difference between T1 and T2 is 30°C to 50°C.

[0031] In one embodiment, T1 is 100°C to 200°C.

[0032] In one embodiment, T2 is 150°C to 250°C.

[0033] In one embodiment, the distal end of the PET heat shrink tubing is subjected to a heat shrinking process, and the distal end of the PET heat shrink tubing is uniformly heat-shrinked.

[0034] In one embodiment, the proximal end of the PET heat shrink tubing undergoes a two-stage heat shrinking process, resulting in uniform heat shrinkage of the proximal end of the PET heat shrink tubing.

[0035] In one embodiment, the heat shrinking speed of the distal end of the PET heat shrink tubing in the direction from the distal end to the proximal end of the alloy core wire is the same as the heat shrinking speed of the proximal end of the PET heat shrink tubing in the direction from the distal end to the proximal end of the alloy core wire.

[0036] In one embodiment, the distal end of the PET heat shrink tubing is subjected to heat shrinking treatment, and the heat shrinking speed of the distal end of the PET heat shrink tubing is 0.5 mm / s to 3 mm / s.

[0037] In one embodiment, the proximal end of the PET heat shrink tubing undergoes a two-stage heat shrinking process, with the heat shrinking speed of the proximal end of the PET heat shrink tubing being 0.5 mm / s to 3 mm / s.

[0038] In one embodiment, at a heat shrinking speed of D1, a section of the distal end of the PET heat shrink tubing is heat-shrinked.

[0039] At a heat shrinking rate of D2, the proximal end of the PET heat shrink tubing is subjected to a two-stage heat shrinking process.

[0040] Where D1 < D2.

[0041] In one embodiment, D1 is 0, and the distal end of the PET heat shrink tubing is subjected to a heat shrink treatment for a duration of 1 to 2 minutes.

[0042] In one embodiment, D2 is 0.5 mm / s to 3 mm / s.

[0043] In one embodiment, the distal end of the PET heat shrink tubing is subjected to a heat shrinking process at a constant temperature.

[0044] In one embodiment, the proximal end of the PET heat shrink tubing undergoes a two-stage heat shrinking process, wherein the PET heat shrink tubing is heat-shrinked at a constant temperature.

[0045] In one embodiment, the heat shrinking temperature for the distal end of the PET heat shrink tubing is the same as the heat shrinking temperature for the proximal end of the PET heat shrink tubing.

[0046] In one embodiment, the heat shrinking temperature for heat shrinking the distal end of the PET heat shrink tubing is 100°C to 200°C.

[0047] In one embodiment, the heat shrinking temperature for the two-stage heat shrinking treatment of the proximal end of the PET heat shrink tubing is 100°C to 200°C.

[0048] In one embodiment, at a temperature of T3 and a heat shrinking rate of D3, a section of heat shrinking treatment is performed on the distal end of the PET heat shrink tubing.

[0049] At a temperature of T4 and a heat shrinking rate of D4, the proximal end of the PET heat shrink tubing is subjected to a two-stage heat shrinking process.

[0050] Where T3 > T4, D3 < D4, and T4 ≥ 100℃.

[0051] In one embodiment, the temperature difference between T3 and T4 is 10°C to 20°C.

[0052] In one embodiment, T3 is 120°C to 220°C.

[0053] In one embodiment, T4 is 100°C to 200°C.

[0054] In one embodiment, D3 is 0, and a heat shrink treatment is performed on the distal end of the PET heat shrink tubing for a dwell time of 30-60 seconds.

[0055] In one embodiment, D4 is 0.5 mm / s to 3 mm / s.

[0056] In one embodiment, the distal end of the PET heat shrink tubing is subjected to a heat shrinking process at a constant temperature.

[0057] In one embodiment, the proximal end of the PET heat shrink tubing undergoes a two-stage heat shrinking process, wherein the PET heat shrink tubing is heat-shrinked at a constant temperature.

[0058] In one embodiment, the distal end of the PET heat shrink tubing is subjected to a heat shrinking process, and the distal end of the PET heat shrink tubing is uniformly heat-shrinked.

[0059] In one embodiment, the proximal end of the PET heat shrink tubing undergoes a two-stage heat shrinking process, resulting in uniform heat shrinkage of the proximal end of the PET heat shrink tubing.

[0060] In one embodiment, the TPU impregnation layer undergoes a tear-away heat-shrinkable leveling process, the specific steps of which are as follows:

[0061] The TPU impregnation layer is leveled and positioned so that the distal end of the alloy core wire is sleeved with a tear-off heat shrink tubing, and the tear-off heat shrink tubing partially overlaps the distal end of the PET heat shrink tubing.

[0062] The tearable heat shrink tubing undergoes a secondary heat shrinking and leveling process to sequentially heat shrink the tearable heat shrink tubing along the direction from the proximal end to the distal end of the alloy core wire. The TPU impregnation layer softens and is squeezed and deformed within the tearable heat shrink tubing, and the PET heat shrink tubing overlapped by the tearable heat shrink tubing softens and is squeezed and deformed within the tearable heat shrink tubing.

[0063] In one embodiment, the heat shrinking temperature for the secondary heat shrinking and leveling treatment of the tearable heat shrink tubing is 200°C to 250°C.

[0064] In one embodiment, the tearable heat shrink tubing undergoes a secondary heat shrinking and leveling process, and the heat shrinking speed of the tearable heat shrink tubing is 0.8 mm / min to 1.2 mm / min.

[0065] In one embodiment, the alloy core wire is further provided with a coiled spring, the distal end of the coiled spring and the distal end of the alloy core wire being thermally fused together to form a distal ball head, the TPU impregnation layer being formed on the proximal ends of the coiled spring and the alloy core wire, and the PET heat shrink tubing being formed on the proximal end of the alloy core wire; and,

[0066] After the step of performing a tear-away heat-shrinking leveling treatment on the TPU impregnation layer, the method for forming the insulation structure based on electrocoagulation wire further includes the following steps:

[0067] The alloy core wire is subjected to a head-end exposure treatment to form an electrocoagulation zone at its distal end. The peripheral wall of the alloy core wire located in the electrocoagulation zone is exposed to the TPU extraction layer. A plurality of penetration holes are formed on the TPU extraction layer on the distal end ball located in the electrocoagulation zone. The distal end face of the alloy core wire is exposed to the TPU extraction layer through each of the penetration holes.

[0068] In one embodiment, the porosity and / or pore size of the infiltration holes on the distal end face of the alloy core wire located in the electrocoagulation zone gradually increase from the geometric center toward the periphery.

[0069] In one embodiment, the hardness of the TPU impregnation layer is 70A to 90A.

[0070] In one embodiment, the flexural modulus of the TPU impregnation layer is 20 MPa to 35 MPa.

[0071] In one embodiment, the Poisson's ratio of the TPU extract layer is 0.45 to 0.5.

[0072] In one embodiment, the length of the electrocoagulation zone is 1 mm to 5 mm.

[0073] In one embodiment, the diameter of the distal ball head is 0.2 mm to 0.3 mm.

[0074] In one embodiment, before the step of exposing the head end of the alloy core wire and after the step of performing a tear-away heat-shrinkable leveling treatment on the TPU impregnation layer, the method for forming the insulation structure based on the electrocoagulated conductor wire further includes the following steps:

[0075] The TPU extraction layer is subjected to a functional coating adhesion treatment so that a hydrophilic coating is attached to at least the surface of the TPU extraction layer, and the hydrophilic coating is attached to the distal end of the PET heat shrink tubing.

[0076] In one embodiment, the pore size of the penetration pores in the TPU extraction layer located in the electrocoagulation zone satisfies the following condition:

[0077] ;

[0078] Where θ is the angle formed by the intersection of the straight line connecting the point on the arc surface of the distal ball head to the center of the distal ball head and the axis; d(θ) is the diameter of the penetration hole; t0 is the thickness of the TPU extraction layer corresponding to that point; k is 0.08~0.18; δ is 0.1~0.3.

[0079] In one embodiment, the porosity of the penetration pores in the TPU extraction layer located in the electrocoagulation zone satisfies the following condition:

[0080] ;

[0081] ;

[0082] Where θ is the angle formed by the intersection of the straight line connecting the points on the arc surface of the distal ball head to the center of the distal ball head and the axis; ρ(θ) is the porosity of the infiltration hole; ρ max The maximum allowable opening ratio is 20%~30%; n0 is the top base density of 10%~20%; β is 0.5~0.8.

[0083] In one embodiment, the porosity and pore size of the penetration pores in the TPU extraction layer located in the electrocoagulation zone are as follows:

[0084] .

[0085] An insulating structure based on an electrocoagulation wire is formed by the forming method for an insulating structure based on an electrocoagulation wire described in any of the above embodiments.

[0086] An electrocoagulation conductor includes a functional coating and an insulating structure based on the electrocoagulation conductor as described in any of the above embodiments, wherein the functional coating is attached together to the TPU impregnation layer, the PET heat shrink tubing, and the proximal end of the alloy core wire.

[0087] Compared with the prior art, the present invention has at least the following advantages:

[0088] The molding method for the insulation structure based on electrocoagulation wire of the present invention involves sequentially heat-shrinking the PET heat-shrink tubing along the distal end to the proximal end of the alloy core wire. This softens the TPU impregnated layer overlapping the PET heat-shrink tubing and causes it to be extruded and deformed within the PET heat-shrink tubing towards the proximal end of the alloy core wire. This achieves uniform distribution within the PET heat-shrink tubing by gradually extruding the softened TPU impregnated layer in a softened state along the distal end to the proximal end of the alloy core wire, even under space constraints during the sequential heat shrinking of the PET heat-shrink tubing. This improves the uniformity of the insulation structure thickness at the overlap between the PET heat-shrink tubing and the PET impregnated layer. Furthermore, a tear-away heat-shrinkable leveling process is performed on the TPU impregnated layer. The design incorporates a tear-off heat-shrinkable tube fitted onto a TPU-extracted layer, with at least a partial heat-shrinkable sleeve over the distal end of a PET heat-shrinkable tube. This causes the TPU-extracted layer to soften and deform within the tear-off heat-shrinkable tube. Specifically, at the overlap between the PET heat-shrinkable tube and the TPU-extracted layer, and throughout the entire TPU-extracted layer, the TPU-extracted layer and PET heat-shrinkable tube gradually soften and deform under the limited heat-shrinkable space of the tear-off heat-shrinkable tube. This, in turn, causes the space enclosed by the inner diameter of the tear-off heat-shrinkable tube to level the thickness of the TPU-extracted layer and PET heat-shrinkable tube, effectively improving the uniformity of the thickness of the TPU-extracted layer and PET heat-shrinkable tube. This, in turn, improves the uniformity of the insulation structure thickness on the electrocoagulation wire, mitigating the problem of electric field imbalance and thus effectively reducing clinical risks. Attached Figure Description

[0089] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0090] Figure 1 This is a partial view of the electrocoagulation guide wire mentioned in the background art of this invention;

[0091] Figure 2 This is a partial view of an electrocoagulation guidewire according to an embodiment of the present invention.

[0092] Figure 3 for Figure 2 Another partial view of the electrocoagulation wire shown. Detailed Implementation

[0093] The present application will be further described in detail below with reference to the embodiments and examples. It should be understood that these embodiments and examples are for illustrative purposes only and are not intended to limit the scope of the present application. The purpose of providing these embodiments and examples is to enable a more thorough and comprehensive understanding of the disclosure of the present application. It should also be understood that the present application can be implemented in many different forms and is not limited to the embodiments and examples described herein. Those skilled in the art can make various modifications or alterations without departing from the spirit of the present application, and the equivalent forms obtained also fall within the protection scope of the present application. Furthermore, numerous specific details are set forth in the following description to provide a fuller understanding of the present application. It should be understood that the present application can be implemented without one or more of these details.

[0094] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0095] In this invention, the technical features described in an open-ended manner include both closed-ended technical solutions composed of the listed features and open-ended technical solutions that include the listed features.

[0096] In this invention, numerical intervals (i.e., numerical ranges) are involved. Unless otherwise specified, the selected numerical distributions within the aforementioned numerical intervals are considered continuous, and include the two endpoints (i.e., the minimum and maximum values) of the numerical range, as well as every value between these two endpoints. Unless otherwise specified, when a numerical interval refers only to integers within that interval, it includes the two endpoint integers of the numerical range, as well as every integer between the two endpoints. In this document, this is equivalent to directly listing every integer. For example, if t is an integer selected from 1 to 10, it means that t is any integer selected from the group of integers consisting of 1, 2, 3, 4, 5, 6, 7, 8, 9, and 10. Furthermore, when multiple ranges are provided to describe features or characteristics, these ranges can be merged. In other words, unless otherwise specified, the ranges disclosed herein should be understood to include any and all subranges to which they are included.

[0097] Unless otherwise specified, the temperature parameters in this invention can be either constant temperature treatment or vary within a certain temperature range. It should be understood that constant temperature treatment allows temperature fluctuations within the precision range controlled by the instrument. Fluctuations are permitted within ranges such as ±5℃, ±4℃, ±3℃, ±2℃, and ±1℃.

[0098] This application provides a method for forming an insulating structure based on an electrocoagulating conductor wire. The above-mentioned method for forming an insulation structure based on electrocoagulation wire includes the following steps: obtaining an alloy core wire; performing an extraction treatment on the alloy core wire to form a TPU extraction layer at the distal end of the alloy core wire; performing a positioning treatment on the extracted alloy core wire to attach a PET heat shrink tubing to the proximal end of the alloy core wire, with the PET heat shrink tubing partially overlapping the proximal end of the TPU extraction layer; performing a heat shrinking and leveling treatment on the PET heat shrink tubing to sequentially heat shrink the PET heat shrink tubing from the distal end to the proximal end of the alloy core wire, and softening the TPU extraction layer overlapping the PET heat shrink tubing and extruding and deforming it within the PET heat shrink tubing towards the proximal end of the alloy core wire; performing a tear-away heat shrinking and leveling treatment on the TPU extraction layer to attach a tear-away heat shrink tubing to the TPU extraction layer, with the tear-away heat shrink tubing at least partially heat-shrinking and attaching to the distal end of the PET heat shrink tubing, and softening the TPU extraction layer and extruding and deforming it within the tear-away heat shrink tubing.

[0099] To better understand the molding method of the insulation structure based on electrocoagulation wire of this application, the molding method of the insulation structure based on electrocoagulation wire of this application will be further explained below:

[0100] Please refer to the following: Figure 2 One embodiment of the molding method for an insulation structure based on an electrocoagulation wire includes the following steps:

[0101] S100, Obtain alloy core wire 100. It can be understood that alloy core wire 100 is a core wire obtained by forming alloy material.

[0102] S200: The alloy core wire 100 undergoes an extraction treatment to form a TPU extraction layer 200 at its distal end. It is understood that the TPU extraction layer 200 at the distal end of the alloy core wire 100 provides good flexibility and relatively good insulation. This ensures effective insulation at the distal end of the electrocoagulation guidewire while maintaining its flexibility, thereby ensuring effective bending adaptation of the guidewire within the blood vessel. Further, the extraction treatment of the alloy core wire 100 is specifically performed as follows: TPU is first dissolved into a liquid state, and then the liquid TPU is applied to the distal end of the alloy core wire 100 through an extraction process to form the TPU extraction layer 200. Further, the extraction treatment of the alloy core wire 100 is performed under vacuum conditions.

[0103] S300: The alloy core wire 100 after impregnation treatment is positioned so that a PET heat shrink tubing 300 is sleeved on the proximal end of the alloy core wire 100, and the PET heat shrink tubing 300 partially overlaps the proximal end of the TPU impregnation layer 200. It can be understood that first sleeved the PET heat shrink tubing 300 on the proximal end of the alloy core wire 100, and partially overlaps it on the proximal end of the TPU impregnation layer 200, ensures effective control of the sleeve position of the PET heat shrink tubing 300 after heat shrinking.

[0104] S400, Perform a heat shrinking and leveling process on the PET heat shrink tubing 300 so that the PET heat shrink tubing 300 is sequentially heat-shrinked along the direction from the far end to the near end of the alloy core wire 100, and the TPU impregnation layer 200 overlapping the PET heat shrink tubing 300 is softened and extruded and deformed in the PET heat shrink tubing 300 towards the near end of the alloy core wire 100. It is understandable that when the PET heat shrink tubing 300 is heat-shrinkably sleeved onto the TPU impregnation layer 200, in order to achieve the insulation effect of the electrocoagulation guide wire, the PET heat shrink tubing 300 needs to partially overlap the TPU impregnation layer 200. However, this results in an increase in the thickness of the insulation portion corresponding to the overlap, thereby affecting the electric field distribution. In order to reduce the clinical risks caused by uneven electric field distribution of the electrocoagulation guide wire, in this application, after the PET heat shrink tubing 300 is positioned, the PET heat shrink tubing 300 is sequentially heat-shrinked along the direction from the distal end to the proximal end of the alloy core wire 100, so that the TPU impregnation layer 200 overlapped by the PET heat shrink tubing 300 softens and moves towards the alloy core wire 100 within the PET heat shrink tubing 300. The TPU-extracted layer 200 overlapping with the PET heat-shrink tubing 300 is gradually squeezed and evenly distributed within the PET heat-shrink tubing 300 in a softened state, under space constraints, as the PET heat-shrink tubing 300 is sequentially heat-shrinked along the distal to proximal direction of the alloy core wire 100. This improves the uniformity of the insulation structure thickness at the overlap between the PET heat-shrink tubing 300 and the PET-extracted layer, thus improving the uniformity of the insulation structure thickness on the electrocoagulation guide wire, reducing the problem of electric field distribution imbalance, and effectively reducing clinical risks.

[0105] S500, the TPU impregnation layer 200 is subjected to a tearable heat shrink leveling treatment so that a tearable heat shrink tube (not shown) is sleeved on the TPU impregnation layer 200, and the tearable heat shrink tube is at least partially heat-shrinked and sleeved on the far end of the PET heat shrink tube 300, and the TPU impregnation layer 200 is softened and squeezed and deformed inside the tearable heat shrink tube. It is understood that the TPU extraction layer 200 is formed through extraction, which means that the overall thickness uniformity of the TPU extraction layer 200 cannot meet the requirements for high-precision surgical scenarios such as neurointervention and cardiac ablation. Therefore, in this application, after performing a heat-shrinking and leveling treatment on the PET heat-shrink tubing 300 to improve the thickness uniformity of the insulation structure at the overlap between the PET heat-shrink tubing 300 and the PET extraction layer, a further tearable heat-shrinking and leveling treatment is performed on the TPU extraction layer 200. This ensures that a tearable heat-shrink tubing is fitted onto the TPU extraction layer 200, and that at least part of the tearable heat-shrink tubing is heat-shrinkably fitted onto the PET heat-shrink tubing. At the distal end of the heat shrink tubing 300, the TPU-extracted layer 200 softens and deforms within the tearable heat shrink tubing. This deformation occurs at the overlap between the PET heat shrink tubing 300 and the TPU-extracted layer 200, as well as at the TPU-extracted layer 200 as a whole. Under the limited heat shrink space of the tearable heat shrink tubing, the TPU-extracted layer 200 and the PET heat shrink tubing 300 gradually soften and deform. This, in turn, causes the space enclosed by the inner diameter of the tearable heat shrink tubing to level the thickness of the TPU-extracted layer 200 and the PET heat shrink tubing 300, further effectively improving the uniformity of the thickness of the TPU-extracted layer 200 and the PET heat shrink tubing 300.

[0106] The aforementioned method for forming an insulation structure based on electrocoagulation wire involves sequentially heat-shrinking the PET heat-shrink tubing 300 along the distal to proximal direction of the alloy core wire 100. This softens the TPU impregnated layer 200 overlapping the PET heat-shrink tubing 300 and causes it to deform within the PET heat-shrink tubing 300 towards the proximal end of the alloy core wire 100. This method achieves uniform distribution within the PET heat-shrink tubing 300 by gradually extruding the TPU impregnated layer 200 in a softened state along the distal to proximal direction of the alloy core wire 100, despite space constraints caused by the sequential heat-shrinking of the PET heat-shrink tubing 300. This improves the uniformity of the insulation structure thickness at the overlap between the PET heat-shrink tubing 300 and the PET impregnated layer. Furthermore, the TPU impregnated layer 200 is further made tearable. Heat shrinking and leveling treatment is performed so that a tear-off heat shrink tubing is fitted onto the TPU impregnation layer 200, and the tear-off heat shrink tubing is at least partially heat-shrinked onto the distal end of the PET heat shrink tubing 300. The TPU impregnation layer 200 softens and deforms within the tear-off heat shrink tubing, thereby gradually softening and deforming the TPU impregnation layer 200 and the PET heat shrink tubing 300 at the overlap of the PET heat shrink tubing 300 and the TPU impregnation layer 200 as a whole, under the limited heat shrinking space of the tear-off heat shrink tubing. This further promotes the leveling of the thickness of the TPU impregnation layer 200 and the PET heat shrink tubing 300 within the space enclosed by the inner diameter of the tear-off heat shrink tubing, and further effectively improves the thickness uniformity of the TPU impregnation layer 200 and the PET heat shrink tubing 300, that is, improves the thickness uniformity of the insulation structure on the electrocoagulation guide wire, reduces the problem of electric field distribution imbalance, and thus effectively reduces clinical risks.

[0107] I understand, please refer to the above as well. Figure 2Ideally, the electric field distribution of a uniform insulation layer is parallel and uniform, with consistent electric intensity. However, when the insulation layer thickness is uneven, the electric field concentrates in areas with thinner insulation, creating a localized electric field enhancement effect. This makes thinner areas more susceptible to breakdown. If the overall insulation structure formed by the TPU impregnation layer 200 or PET heat shrink tubing 300 has an uneven thickness distribution, it is prone to localized breakdown, causing current to leak into the surrounding normal tissue and resulting in non-target areas being damaged. Burns and the formation of electrocoagulation thrombi in non-target areas increase clinical risks. Furthermore, the electric field strength in the effective electrocoagulation zone distal to the electrocoagulation guidewire decreases due to current shunting, leading to reduced electrocoagulation efficiency. In addition, uneven thickness of the PU-extracted layer or PET heat-shrink tubing 300 causes stress concentration during advancement in areas with thinner TPU-extracted layers 200, making the guidewire prone to breakage at these points during repeated bending, potentially causing medical accidents. In this application, the TPU-extracted layer 200 overlapping with the PET heat-shrink tubing 300... 0. Under space constraints, as the PET heat shrink tubing 300 is sequentially heat-shrinked along the distal to proximal direction of the alloy core wire 100, the TPU impregnated layer 200 overlapping with the PET heat shrink tubing 300 is gradually extruded in a softened state along the distal to proximal direction of the alloy core wire 100 to achieve uniform distribution within the PET heat shrink tubing 300. This initially achieves uniform thickness at the overlap between the PET heat shrink tubing 300 and the TPU impregnated layer 200. Combined with the limited heat shrinking space of the tearable heat shrink tubing, this gradually achieves uniform thickness distribution of the TPU impregnated layer 200 and PE at various locations. The softening and extrusion of the T-type heat shrink tubing 300 causes the space enclosed by the inner diameter of the tearable heat shrink tubing to level the thickness of the TPU impregnation layer 200 and the PET heat shrink tubing 300. This effectively improves the uniformity of the thickness of the TPU impregnation layer 200 and the PET heat shrink tubing 300, thereby improving the uniformity of the insulation structure thickness on the electrocoagulation guide wire. This reduces the problem of electric field distribution imbalance, thereby reducing the local breakdown of the TPU impregnation layer 200 or the PET heat shrink tubing 300 during the electrocoagulation process and ensuring the electrocoagulation effect.

[0108] That's understandable, please refer to it as well. Figure 2After solvent drying, the TPU extract layer 200 is prone to micropores and thickness fluctuations, especially due to the influence of the spring winding on the surface of the alloy core wire 100. This can cause the TPU extract layer 200 located between adjacent turns of the spring to even indent, further exacerbating the uneven thickness distribution of the TPU extract layer 200 on the electrocoagulation guide wire. Adding additives to the TPU solution formed by the TPU extract layer 200 or modifying the TPU is unlikely to effectively improve the thickness uniformity of the TPU extract layer 200. Similarly, eliminating air bubbles through hot pressing is also unlikely to effectively improve the thickness uniformity of the TPU extract layer 200. Therefore, the application of a tear-off heat-shrink tubing to the TPU extract layer 200 is necessary. During heat shrinking, the heat shrink tubing applies uniform radial pressure to the TPU impregnation layer 200, causing it to soften and ripple within the tearable heat shrink tubing. This forces the filling of depressions and micropores, effectively reshaping the thickness of the TPU impregnation layer 200 and improving its uniformity, thus ensuring better electrocoagulation. Furthermore, the tearable heat shrink tubing further smooths the overlap between the TPU impregnation layer 200 and the PET heat shrink tubing 300, further improving the uniformity of the insulation structure formed by the TPU impregnation layer 200 and the PET heat shrink tubing 300.

[0109] It should be noted that after the tear-off heat shrink tubing is heat-shrinked, the tear-off heat shrink tubing is peeled off and is not part of the structure that is ultimately formed in the electrocoagulation wire.

[0110] Please refer to the following: Figure 2 In one embodiment, the overlap length of the PET heat shrink tubing 300 on the TPU impregnation layer 200 is 2mm to 5mm. Further, the thickness of the TPU impregnation layer 200 is 0.02mm to 0.04mm. Further, the thickness of the PET heat shrink tubing 300 is 0.01mm to 0.05mm, ensuring effective insulation at the overlap between the PET heat shrink tubing 300 and the TPU impregnation layer 200.

[0111] Please refer to the following: Figure 2 In one embodiment, the outer diameter of the overlap between the PET heat shrink tubing 300 and the TPU impregnation layer 200 is the same as the outer diameter of the near end of the TPU impregnation layer 200. This effectively flattens the thickness of the overlap between the PET heat shrink tubing 300 and the TPU impregnation layer 200 to be the same as the outer diameter of the near end of the TPU impregnation layer 200, thus achieving better thickness uniformity of the insulation structure formed by the PET heat shrink tubing 300 and the TPU impregnation layer 200.

[0112] Please refer to the following: Figure 2In one embodiment, the outer diameter of the distal end of the alloy core wire 100 is smaller than the outer diameter of the proximal end of the alloy core wire 100. Further, in the direction from the distal end to the proximal end of the alloy core wire 100, the outer diameter of the distal end gradually increases. Further, the outer diameter of the distal end of the alloy core wire 100 is 0.08 mm to 0.36 mm. Further, the distal end of the alloy core wire 100 is a nickel-titanium alloy core wire 100. Further, the proximal end of the alloy core wire 100 is a stainless steel alloy core wire 100. Further, the distal end of the alloy core wire 100 is welded to the proximal end of the alloy core wire 100. Further, at the connection between the proximal end and the distal end of the alloy core wire 100, the outer diameter of the proximal end of the alloy core wire 100 is the same as the outer diameter of the distal end of the alloy core wire 100, and PET is at least partially sleeved at the connection between the proximal end and the distal end of the alloy core wire 100. It is understandable that insulation is difficult to guarantee when the thickness of the TPU impregnation layer is small, and the outer diameter of the near end of the alloy core wire 100 is large. Therefore, in order to reduce the further increase of the outer diameter of the electrocoagulation wire, the near end of the alloy core wire 100 is insulated through the PET heat shrink tubing 300. The PET heat shrink tubing 300 also has very good insulation when the thickness is small, thus ensuring the effective insulation of the electrocoagulation wire.

[0113] Please refer to the following: Figure 2 In one embodiment, the PET heat shrink tubing 300 undergoes a heat shrink leveling process, the specific steps of which are as follows:

[0114] The distal end of the PET heat shrink tube 300 is subjected to heat shrink treatment so that the distal end of the PET heat shrink tube 300 is sequentially heat-shrinked along the distal end of the alloy core wire 100 toward the proximal end, and the TPU impregnation layer 200 overlapped by the PET heat shrink tube 300 is softened and extruded and deformed in the PET heat shrink tube 300 toward the proximal end of the alloy core wire 100.

[0115] The proximal end of the PET heat shrink tubing 300 is subjected to a two-stage heat shrinking process so that the proximal end of the PET heat shrink tubing 300 is sequentially heat-shrinked along the direction from the distal end of the alloy core wire 100 toward the proximal end.

[0116] It can be understood that during the sequential heat shrinking process of the PET heat shrink tube 300 along the direction from the distal end to the proximal end of the alloy core wire 100, the TPU impregnation layer 200 overlapping with the PET heat shrink tube 300 softens and is squeezed and deformed towards the proximal end of the PET heat shrink tube 300. Then, the proximal end of the PET heat shrink tube 300 is sequentially heat-shrinked along the direction from the distal end to the proximal end of the alloy core wire 100, so that the remaining part of the PET heat shrink tube 300, except for the overlapping part with the TPU impregnation layer 200, continues to be sequentially heat-shrinked along the direction from the distal end to the proximal end of the alloy core wire 100, and causes the TPU impregnation layer 200 reaching the proximal end of the PET heat shrink tube 300 to continue to be squeezed and deformed towards the proximal end of the PET heat shrink tube 300, effectively achieving effective leveling of the thickness at the overlap between the TPU impregnation layer 200 and the PET heat shrink tube 300.

[0117] Please refer to the following: Figure 2 In one embodiment, at temperature T1, the distal end of the PET heat shrink tubing 300 undergoes a first-stage heat shrinking treatment. Further, at temperature T2, the proximal end of the PET heat shrink tubing 300 undergoes a second-stage heat shrinking treatment. Further, T1 > T2, and T2 ≥ 100°C. Further, the temperature difference between T1 and T2 is 30°C to 50°C. Further, T1 is 100°C to 200°C. Further, T2 is 150°C to 250°C. Further, the distal end of the PET heat shrink tubing 300 undergoes a first-stage heat shrinking treatment, resulting in uniform heat shrinkage of the distal end. Further, the proximal end of the PET heat shrink tubing 300 undergoes a second-stage heat shrinking treatment, resulting in uniform heat shrinkage of the proximal end. Furthermore, the heat shrinking speed of the distal end of the PET heat shrink tubing 300 along the direction from the distal end to the proximal end of the alloy core wire 100 is the same as the heat shrinking speed of the proximal end of the PET heat shrink tubing 300 along the direction from the distal end to the proximal end of the alloy core wire 100. Furthermore, the distal end of the PET heat shrink tubing 300 undergoes a first-stage heat shrinking treatment, with a heat shrinking speed of 0.5 mm / s to 3 mm / s. Furthermore, the proximal end of the PET heat shrink tubing 300 undergoes a second-stage heat shrinking treatment, with a heat shrinking speed of 0.5 mm / s to 3 mm / s.

[0118] Please refer to the following: Figure 2In other embodiments, at a heat shrinking rate of D1, the distal end of the PET heat shrink tubing 300 undergoes a first-stage heat shrinking treatment. Further, at a heat shrinking rate of D2, the proximal end of the PET heat shrink tubing 300 undergoes a second-stage heat shrinking treatment. Further, D1 < D2. Further, D1 is 0, and the distal end of the PET heat shrink tubing 300 undergoes a first-stage heat shrinking treatment with a dwell time of 1 min to 2 min. Further, D2 is 0.5 mm / s to 3 mm / s. Further, the distal end of the PET heat shrink tubing 300 undergoes a first-stage heat shrinking treatment, and the PET heat shrink tubing 300 is heat-shrinked at a constant temperature. Further, the proximal end of the PET heat shrink tubing 300 undergoes a second-stage heat shrinking treatment, and the PET heat shrink tubing 300 is heat-shrinked at a constant temperature. Further, the heat shrinking temperature for the first-stage heat shrinking treatment of the distal end of the PET heat shrink tubing 300 is the same as the heat shrinking temperature for the second-stage heat shrinking treatment of the proximal end of the PET heat shrink tubing 300. Furthermore, the heat shrinking temperature for the distal end of the PET heat shrink tubing 300 is 100℃~200℃. Furthermore, the heat shrinking temperature for the proximal end of the PET heat shrink tubing 300 is 100℃~200℃. It can be understood that D1 is 0, mainly because the overlap between the TPU impregnation layer 200 and the PET heat shrink tubing 300 is relatively short. When using a hot air gun for heat shrinking, directly controlling the dwell time is sufficient to effectively represent the heat shrinking speed.

[0119] Please refer to the following: Figure 2 In some further embodiments, at a temperature of T3 and a heat shrinking rate of D3, the distal end of the PET heat shrink tubing 300 undergoes a first-stage heat shrinking treatment. Further, at a temperature of T4 and a heat shrinking rate of D4, the proximal end of the PET heat shrink tubing 300 undergoes a second-stage heat shrinking treatment. Further, T3 > T4, D3 < D4, and T4 ≥ 100°C. Further, the temperature difference between T3 and T4 is 10°C to 20°C. Further, T3 is 120°C to 220°C. Further, T4 is 100°C to 200°C. Further, D3 is 0, and the distal end of the PET heat shrink tubing 300 undergoes a first-stage heat shrinking treatment with a dwell time of 30S to 60S. Further, D4 is 0.5mm / s to 3mm / s. Further, the distal end of the PET heat shrink tubing 300 undergoes a first-stage heat shrinking treatment, and the PET heat shrink tubing 300 undergoes constant-temperature heat shrinking. Furthermore, the proximal end of the PET heat shrink tubing 300 undergoes a two-stage heat shrinking process, with the PET heat shrink tubing 300 undergoing constant-temperature heat shrinking. Furthermore, the distal end of the PET heat shrink tubing 300 undergoes a one-stage heat shrinking process, with the distal end of the PET heat shrink tubing 300 undergoing uniform heat shrinking. Furthermore, the proximal end of the PET heat shrink tubing 300 undergoes a two-stage heat shrinking process, with the proximal end of the PET heat shrink tubing 300 undergoing uniform heat shrinking. It can be understood that D3 is 0, mainly considering that the overlap between the TPU impregnation layer 200 and the PET heat shrink tubing 300 is relatively short. When using a hot air gun for heating and shrinking, directly controlling the residence time can effectively represent the heat shrinking speed.

[0120] Please refer to the following: Figure 2 In one embodiment, the TPU impregnation layer 200 undergoes a tear-away heat-shrinkable leveling process, the specific steps of which are as follows:

[0121] The TPU impregnation layer 200 is leveled and positioned so that the distal end of the alloy core wire 100 is fitted with a tear-off heat shrink tubing, and the tear-off heat shrink tubing overlaps the distal end of the PET heat shrink tubing 300.

[0122] The tearable heat shrink tubing undergoes a secondary heat shrinking and leveling process to sequentially heat shrink the tearable heat shrink tubing along the direction from the proximal end to the distal end of the alloy core wire 100. The TPU impregnation layer 200 is softened and deformed within the tearable heat shrink tubing, and the PET heat shrink tubing 300 overlapped with the tearable heat shrink tubing is softened and deformed within the tearable heat shrink tubing.

[0123] It is understandable that the tearable heat shrink tubing overlaps the distal end of the PET heat shrink tubing 300, meaning the tearable heat shrink tubing overlaps the junction of the PET heat shrink tubing 300 and the TPU impregnation layer 200. This further promotes the sequential softening and extrusion deformation of the PET heat shrink tubing 300 and the TPU impregnation layer 200 at the junction within the tearable heat shrink tubing, moving sequentially from the proximal end to the distal end along the alloy core wire 100. This further effectively improves the performance of the PET heat shrink tubing 300. The uniformity of the thickness of the insulation structure formed together with the TPU impregnation layer 200 is improved by applying uniform radial pressure to the TPU impregnation layer 200 during heat shrinking of the tear-off heat shrink tubing. This causes the TPU impregnation layer 200 to soften and deform within the tear-off heat shrink tubing, forcibly filling the depressions and micropores of the TPU impregnation layer 200. This also achieves a reshaping of the overall thickness of the TPU impregnation layer 200, effectively improving the uniformity of the thickness of the TPU impregnation layer 200 and thus ensuring a better electrocoagulation effect.

[0124] Please refer to the following: Figure 2In one embodiment, the tearable heat shrink tubing is FEP heat shrink tubing. Further, the heat shrinking temperature for the secondary heat shrinking and leveling treatment of the tearable heat shrink tubing is 200℃~250℃. Further, the heat shrinking speed of the tearable heat shrink tubing for the secondary heat shrinking and leveling treatment is 0.8mm / min~1.2mm / min. Furthermore, the heat shrinking temperature of the FEP heat shrink tubing is 200℃~250℃, which eliminates the need to increase the heat shrinking temperature of the FEP heat shrink tubing to achieve further flattening at the overlap between the PET heat shrink tubing 300 and the TPU impregnation layer 200. That is, the normal heat shrinking temperature, which is determined by the sequential heat shrinking of the tearable heat shrink tubing along the direction from the near end to the far end of the alloy core wire 100, can effectively achieve further flattening at the overlap between the PET heat shrink tubing 300 and the TPU impregnation layer 200, reshaping the overall thickness uniformity of the TPU impregnation layer 200, and effectively filling the indentations and micropores of the TPU impregnation layer.

[0125] Please refer to the following: Figure 2 and Figure 3 In one embodiment, the alloy core wire 100 is further provided with a coiled spring 500, the distal end of the coiled spring 500 and the distal end of the alloy core wire 100 are thermally fused together to form a distal ball head 10a, a TPU impregnation layer 200 is formed on the proximal ends of the coiled spring 500 and the alloy core wire 100, and a PET heat shrink tube 300 is formed on the proximal end of the alloy core wire 100. Furthermore, after the step of performing a tear-away heat-shrinking leveling treatment on the TPU impregnation layer 200, the method for forming an insulation structure based on electrocoagulation wire further includes the following steps: exposing the head end of the alloy core wire 100 to form an electrocoagulation zone at the distal end of the alloy core wire 100, and exposing the peripheral wall of the alloy core wire 100 located in the electrocoagulation zone to the TPU impregnation layer 200, and forming a plurality of penetration holes on the TPU impregnation layer 200 on the distal ball head 10a located in the electrocoagulation zone, with the distal end face of the alloy core wire 100 exposed to the TPU impregnation layer 200 through each penetration hole.

[0126] It is understood that the distal bulb tip 10a is the tip of the electrocoagulation guidewire. During the advancement of the electrocoagulation guidewire within the blood vessel, the tip of the distal bulb tip 10a directly impacts the vessel wall, especially in curved vessel segments. The friction of the distal bulb tip 10a against the vessel wall can cause damage. Since the distal bulb tip 10a is a rigid structure, this further exacerbates the damage. Therefore, to reduce damage to the vessel wall during the advancement of the electrocoagulation guidewire, this application exposes the tip of the alloy core wire 100. The peripheral wall of the alloy core wire 100 located in the electrocoagulation area is exposed to the TPU extraction layer 200. Multiple penetration holes are formed on the TPU extraction layer 200 on the distal bulb tip 10a located in the electrocoagulation area. The distal end face of the alloy core wire 100 is exposed to the TPU extraction layer 200 through each penetration hole. That is, the TPU extraction layer 200 is applied at the corresponding position in the electrocoagulation area of ​​the electrocoagulation guidewire. In fact, there is also TPU... The hydrophilic coating on the surface of the PU extraction layer 200 is removed by laser, but the TPU extraction layer 200 on the distal bulb 10a is retained. The hydrophilic coating on the TPU extraction layer 200 is also retained. The flexibility of the TPU extraction layer 200 and the hydrophilicity of the hydrophilic coating effectively reduce damage to the vessel wall at the distal bulb 10a of the electrocoagulation guidewire. Furthermore, since the distal bulb 10a is the main area for thrombus electrocoagulation, complete coverage by the TPU extraction layer 200 would affect electrocoagulation efficiency. To ensure electrocoagulation efficiency, this application creates multiple infiltration holes on the TPU extraction layer 200 on the distal bulb 10a located in the electrocoagulation area. The distal end face of the alloy core wire 100 is exposed to the TPU extraction layer 200 through each infiltration hole, allowing blood to pass through the infiltration holes to form a circuit for electrocoagulation and thrombus formation, thus better ensuring the electrocoagulation efficiency of the electrocoagulation guidewire.

[0127] Please refer to the following: Figure 2 and Figure 3 In one embodiment, the porosity and / or pore size of the infiltration holes on the distal end face of the alloy core wire 100 located in the electrocoagulation zone gradually increase from the geometric center toward the periphery. It can be understood that the contact point between the distal bulb tip 10a and the vessel wall is an arc surface, and damage to the vessel wall is primarily caused by the top of the arc surface of the distal bulb tip 10a pressing against the vessel wall. Therefore, the gradual increase in the porosity and / or pore size of the infiltration holes on the distal end face of the alloy core wire 100 located in the electrocoagulation zone from the geometric center toward the periphery ensures that the pore size at the top of the arc surface of the distal bulb tip 10a is small and the number of pores is low, thus better ensuring the elasticity of the TPU extraction layer 200 to reduce damage to the vessel wall. Meanwhile, the gradual increase in the pore size and number of pores at the periphery of the top of the arc surface of the distal bulb tip 10a increases the exposed area of ​​the distal bulb tip 10a, further ensuring the electrocoagulation efficiency of the electrocoagulation guidewire.

[0128] Please refer to the following: Figure 2 and Figure 3 In one embodiment, the TPU extraction layer 200 has a hardness of 70A to 90A. Further, the flexural modulus of the TPU extraction layer 200 is 20MPa to 35MPa. Further, the Poisson's ratio of the TPU extraction layer 200 is 0.45 to 0.5, which effectively ensures a buffering and protective effect on the vessel wall. Further, the length of the electrocoagulation zone is 1mm to 5mm. Further, the diameter of the distal bulb 10a is 0.2mm to 0.3mm, which is beneficial for a balanced distribution of electrocoagulation efficiency and buffering protection on the vessel wall.

[0129] Please refer to the following: Figure 2 and Figure 3 In one embodiment, before the step of exposing the head end of the alloy core filament 100 and after the step of performing a tear-away heat-shrinkable leveling treatment on the TPU impregnation layer 200, the method for forming the insulation structure based on the electrocoating conductor further includes the following steps: applying a functional coating to the TPU impregnation layer 200 so that a hydrophilic coating 600 is attached to at least the surface of the TPU impregnation layer 200, and the hydrophilic coating 600 is attached to the distal end of the PET heat-shrinkable tubing 300, thereby better ensuring the surface smoothness of the corresponding area of ​​the TPU impregnation layer 200 of the electrocoating conductor. Further, applying a functional coating to the TPU impregnation layer so that a hydrophobic coating is also formed on the proximal end of the alloy core filament, the distal end of which extends to the proximal end of the PET heat-shrinkable tubing.

[0130] In one embodiment, the pore size of the penetration pores in the TPU extraction layer located in the electrocoagulation zone satisfies the following condition:

[0131] ;

[0132] Where θ is the angle formed by the intersection of the straight line connecting the point on the arc surface of the distal ball head to the center of the distal ball head and the axis; d(θ) is the diameter of the penetration hole; t0 is the thickness of the TPU extraction layer corresponding to that point; k is 0.08~0.18; δ is 0.1~0.3.

[0133] In one embodiment, the porosity of the TPU extraction layer located in the electrocoagulation zone satisfies the following condition:

[0134] ;

[0135] ;

[0136] Where θ is the angle formed by the intersection of the straight line connecting the points on the arc surface of the distal ball head to the center of the distal ball head and the axis; ρ(θ) is the porosity of the infiltration hole; ρ maxThe maximum allowable opening ratio is 20%~30%; n0 is the top base density of 10%~20%; β is 0.5~0.8.

[0137] In one embodiment, the porosity and pore size of the TPU extraction layer located in the electrocoagulation zone are as follows:

[0138]

[0139] It is understandable that, as mentioned earlier, the TPU layer corresponding to the electrocoagulation zone of the electrocoagulation guidewire can reduce damage to the blood vessel wall, while the inclusion pores allow blood to seep in to ensure electrocoagulation efficiency. However, by balancing the pore opening rate and pore size using the formula mentioned above, the following effects can also be achieved in practice, as detailed below:

[0140] Firstly, when the alloy core wire conducts current to the distal bulb tip, if the corresponding distal bulb tip is not completely covered with a TPU extraction layer, the entire arc surface of the distal bulb tip is connected through the blood, causing the current to be dispersed over a larger tissue area. This results in insufficient energy per unit area, leading to a relatively slow electrocoagulation speed and potential damage to surrounding normal tissue due to heat dissipation. In this application, however, because the TPU extraction layer is connected through penetration holes, the area of ​​the distal bulb tip connected through the blood is reduced, resulting in a higher current density corresponding to the penetration holes. This strengthens the adsorption capacity of negatively charged ions in the blood by local tissue discharge, leading to faster hemoglobin aggregation and faster thrombus formation. Based on the above limitations on the pore size and porosity, a better balance between improved electrocoagulation efficiency and buffering protection of the blood vessel wall is achieved. Furthermore, compared to structures where the TPU extraction layer at the distal end is completely ablated, this structure has no step at the distal bulb tip, allowing for a smooth transition and further reducing damage to the blood vessel wall.

[0141] Secondly, because the distal bulb of the electrocoagulation guidewire has a TPU extraction layer, and the distal bulb is only exposed to the TPU extraction layer through the infiltration hole, the contact area between the thrombus formed on the electrocoagulation area of ​​the electrocoagulation guidewire and the electrocoagulation area is reduced. This reduces the adhesion area of ​​the thrombus on the electrocoagulation area of ​​the electrocoagulation guidewire, thereby reducing the adhesion strength of the thrombus to the electrocoagulation area of ​​the electrocoagulation guidewire. This is more conducive to the detachment of the electrocoagulation guidewire from the thrombus and further reduces the clinical risk.

[0142] This application also provides an insulation structure based on electrocoagulation wire, which is formed by the molding method of the insulation structure based on electrocoagulation wire in any of the above embodiments.

[0143] This application also provides an electrocoagulation conductor, including a functional coating and an insulation structure based on the electrocoagulation conductor according to any of the above embodiments, wherein the functional coating is attached together to the TPU impregnation layer, the PET heat shrink tubing and the proximal end of the alloy core wire.

[0144] The electrocoagulation wire assembled from the insulation structure based on the electrocoagulation wire prepared by the above-described method has a breakdown voltage as high as 500V.

[0145] The electrocoagulation wire assembled using the insulation structure preparation method based on the electrocoagulation wire in any of the above embodiments has a higher electrocoagulation efficiency when placed in pig blood compared to the same electrocoagulation wire after further peeling off the TPU extraction layer and hydrophilic coating on the distal ball head and then placing it back in the pig blood. Specifically, for low current (1mA) electrocoagulation, the rate of thrombus formation is increased by up to 50%, while for high current (4mA) electrocoagulation, the rate of thrombus formation is increased by up to 20%.

[0146] Compared with the prior art, the present invention has at least the following advantages:

[0147] The molding method of the insulation structure based on electrocoagulation wire of the present invention involves sequentially heat-shrinking the PET heat-shrink tubing 300 along the distal end to the proximal end of the alloy core wire 100. This softens the TPU impregnated layer 200 overlapping the PET heat-shrink tubing 300 and causes it to be extruded and deformed within the PET heat-shrink tubing 300 towards the proximal end of the alloy core wire 100. This achieves uniform distribution within the PET heat-shrink tubing 300 by gradually extruding the TPU impregnated layer 200 in a softened state along the distal end to the proximal end of the alloy core wire 100, under space constraints during the sequential heat-shrinking of the PET heat-shrink tubing 300. This improves the uniformity of the insulation structure thickness at the overlap between the PET heat-shrink tubing 300 and the PET impregnated layer. Furthermore, the TPU impregnated layer 200 is further torn... The heat-shrinkable and leveling process involves attaching a tear-off heat-shrinkable tube to the TPU-extracted layer 200, with at least a partial heat-shrinkable connection between the tear-off heat-shrinkable tube and the distal end of the PET heat-shrinkable tube 300. This softens the TPU-extracted layer 200 and causes it to deform within the tear-off heat-shrinkable tube. Specifically, this process, along with the overlap between the PET heat-shrinkable tube 300 and the TPU-extracted layer 200, and the TPU-extracted layer 200 as a whole, gradually softens and deforms the TPU-extracted layer 200 and the PET heat-shrinkable tube 300 within the limited space of the heat-shrinkable tube. This further leveles the thickness of the TPU-extracted layer 200 and the PET heat-shrinkable tube 300 within the space enclosed by the inner diameter of the tear-off heat-shrinkable tube, effectively improving the uniformity of the thickness of the TPU-extracted layer 200 and the PET heat-shrinkable tube 300. This improves the uniformity of the insulation structure thickness on the electrocoagulation guide wire, reduces the problem of electric field imbalance, and thus effectively reduces clinical risks.

[0148] The embodiments described above merely illustrate several implementation methods of this application to facilitate a detailed understanding of the technical solutions of this application, but should not be construed as limiting the scope of protection of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the scope of protection of this application. Furthermore, it should be understood that after reading the above teachings of this application, those skilled in the art can make various alterations or modifications to this application, and the equivalent forms obtained also fall within the scope of protection of this application. It should also be understood that technical solutions obtained by those skilled in the art based on the technical solutions provided in this application through logical analysis, reasoning, or limited experimentation are all within the scope of protection of the appended claims. Therefore, the scope of protection of this patent application should be determined by the content of the appended claims, and the specification and drawings can be used to interpret the content of the claims.

Claims

1. A method for forming an insulating structure based on an electrocoagulating wire, characterized in that, Includes the following steps: Obtain alloy core wire; The alloy core wire is subjected to an extraction treatment to form a TPU extraction layer at the distal end of the alloy core wire. The alloy core wire after the extraction treatment is positioned so that a PET heat shrink tube is sleeved on the proximal end of the alloy core wire, and the PET heat shrink tube partially overlaps the proximal end of the TPU extraction layer. The PET heat shrink tubing is subjected to a heat shrinking and leveling process to make the PET heat shrink tubing sequentially heat shrink from the far end to the near end along the direction of the alloy core wire. The TPU impregnation layer overlapped by the PET heat shrink tubing is softened and squeezed and deformed in the PET heat shrink tubing towards the near end of the alloy core wire, so as to initially promote the uniformity of the thickness at the overlap of the PET heat shrink tubing and the TPU impregnation layer. The TPU impregnation layer is subjected to a tearable heat shrink leveling treatment so that a tearable heat shrink tube is sleeved on the TPU impregnation layer, and the tearable heat shrink tube is at least partially heat-shrinked and sleeved on the far end of the PET heat shrink tube. The TPU impregnation layer softens and is squeezed and deformed in the tearable heat shrink tube, and the PET heat shrink tube overlapped by the tearable heat shrink tube softens and is squeezed and deformed in the tearable heat shrink tube, further promoting the uniformity of the thickness of the TPU impregnation layer and the PET heat shrink tube. The method for forming an insulation structure based on electrocoagulation wire, after the step of performing a tear-away heat-shrinking leveling treatment on the TPU impregnation layer, further includes the following step: exposing the head end of the alloy core wire to form an electrocoagulation zone at the far end of the alloy core wire, and exposing the peripheral wall of the alloy core wire located in the electrocoagulation zone to the TPU impregnation layer.

2. The method for forming an insulating structure based on an electrocoagulating wire according to claim 1, characterized in that, The overlap length of the PET heat shrink tubing on the TPU impregnation layer is 2mm to 5mm; and / or The thickness of the TPU impregnation layer is 0.02mm~0.04mm; and / or, The thickness of the PET heat shrink tubing is 0.01mm~0.05mm; and / or, The outer diameter of the overlap between the PET heat shrink tubing and the TPU impregnation layer is the same as the outer diameter of the proximal end of the TPU impregnation layer; and / or... The outer diameter of the distal end of the alloy core wire is smaller than the outer diameter of the proximal end of the alloy core wire; and / or In the direction from the distal end to the proximal end of the alloy core wire, the outer diameter of the distal end of the alloy core wire gradually increases; and / or, The outer diameter of the distal end of the alloy core wire is 0.08 mm to 0.36 mm; and / or, The distal end of the alloy core wire is a nickel-titanium alloy core wire; and / or... The proximal end of the alloy core wire is a stainless steel alloy core wire; and / or... At the junction of the proximal and distal ends of the alloy core wire, the outer diameter of the proximal end of the alloy core wire is the same as the outer diameter of the distal end of the alloy core wire, and the PET heat shrink tubing is at least partially fitted onto the junction of the proximal and distal ends of the alloy core wire; and / or, The removable heat shrink tubing is FEP heat shrink tubing.

3. The method for forming an insulating structure based on an electrocoagulating wire according to claim 1, characterized in that, The PET heat shrink tubing undergoes a heat shrinking and leveling process, and the specific steps are as follows: The distal end of the PET heat shrink tubing is subjected to heat shrinking treatment so that the distal end of the PET heat shrink tubing is sequentially heat-shrinked along the distal end of the alloy core wire toward the proximal end, and the TPU impregnation layer overlapped by the PET heat shrink tubing is softened and extruded and deformed in the PET heat shrink tubing toward the proximal end of the alloy core wire. The proximal end of the PET heat shrink tubing is subjected to a two-stage heat shrinking process, so that the proximal end of the PET heat shrink tubing is sequentially heat-shrinked along the direction from the distal end of the alloy core wire toward the proximal end.

4. The method for forming an insulating structure based on an electrocoagulating wire according to claim 3, characterized in that, At a temperature of T1, a section of the distal end of the PET heat shrink tubing is subjected to heat shrink treatment. At a temperature of T2, the proximal end of the PET heat shrink tubing is subjected to a two-stage heat shrinking process. Where T1 > T2, and T2 ≥ 100℃.

5. The method for forming an insulating structure based on an electrocoagulating wire according to claim 4, characterized in that, The temperature difference between T1 and T2 is 30℃~50℃; and / or, T1 is 150℃~250℃; and / or, T2 is 100℃~200℃; and / or, The distal end of the PET heat shrink tubing undergoes a heat shrinking process, resulting in uniform heat shrinkage of the distal end; and / or, The proximal end of the PET heat shrink tubing undergoes a two-stage heat shrinking process, resulting in uniform heat shrinkage of the proximal end; and / or, The heat shrinking rate of the distal end of the PET heat shrink tubing in the direction from the distal end to the proximal end of the alloy core wire is the same as the heat shrinking rate of the proximal end of the PET heat shrink tubing in the direction from the distal end to the proximal end of the alloy core wire; and / or, The distal end of the PET heat shrink tubing undergoes a heat shrinking process, wherein the heat shrinking speed of the distal end of the PET heat shrink tubing is 0.5 mm / s to 3 mm / s; and / or, The proximal end of the PET heat shrink tubing undergoes a two-stage heat shrinking process, with the heat shrinking speed of the proximal end of the PET heat shrink tubing being 0.5 mm / s to 3 mm / s.

6. The method for forming an insulating structure based on an electrocoagulating wire according to claim 3, characterized in that, At a heat shrinking speed of D1, a section of heat shrinking treatment is performed on the distal end of the PET heat shrink tubing. At a heat shrinking rate of D2, the proximal end of the PET heat shrink tubing is subjected to a two-stage heat shrinking process. Where D1 < D2; or, At a temperature of T3 and a heat shrinking rate of D3, a section of heat shrinking treatment is performed on the distal end of the PET heat shrink tubing. At a temperature of T4 and a heat shrinking rate of D4, the proximal end of the PET heat shrink tubing is subjected to a two-stage heat shrinking process. Where T3 > T4, D3 < D4, and T4 ≥ 100℃.

7. The method for forming an insulating structure based on an electrocoagulating wire according to claim 1, characterized in that, The TPU impregnation layer undergoes a peelable heat-shrinkable leveling process, and the specific steps are as follows: The TPU impregnation layer is leveled and positioned so that the distal end of the alloy core wire is sleeved with a tear-off heat shrink tubing, and the tear-off heat shrink tubing partially overlaps the distal end of the PET heat shrink tubing. The tearable heat shrink tubing undergoes a secondary heat shrinking and leveling process to sequentially heat shrink the tearable heat shrink tubing along the direction from the proximal end to the distal end of the alloy core wire. The TPU impregnation layer softens and is squeezed and deformed within the tearable heat shrink tubing, and the PET heat shrink tubing overlapped by the tearable heat shrink tubing softens and is squeezed and deformed within the tearable heat shrink tubing.

8. The method for forming an insulating structure based on an electrocoagulating wire according to claim 7, characterized in that, The heat shrinking temperature for the secondary heat shrinking and leveling treatment of the tearable heat shrink tubing is 200℃~250℃; and / or, The tearable heat shrink tubing undergoes a secondary heat shrinking and leveling process, with the heat shrinking speed of the tearable heat shrink tubing being 0.8 mm / min to 1.2 mm / min.

9. The method for forming an insulating structure based on an electrocoagulating wire according to claim 1, characterized in that, The alloy core wire is further provided with a coiled spring, the distal end of the coiled spring and the distal end of the alloy core wire are thermally fused together to form a distal ball head, the TPU impregnation layer is formed on the proximal ends of the coiled spring and the alloy core wire, and the PET heat shrink tubing is formed on the proximal end of the alloy core wire; and, After the step of performing a tear-away heat-shrinking leveling treatment on the TPU impregnation layer, the method for forming the insulation structure based on electrocoagulation wire further includes the following steps: The alloy core wire is subjected to a head-end exposure treatment to form an electrocoagulation zone at its distal end. The peripheral wall of the alloy core wire located in the electrocoagulation zone is exposed to the TPU extraction layer. A plurality of penetration holes are formed on the TPU extraction layer on the distal end ball located in the electrocoagulation zone. The distal end face of the alloy core wire is exposed to the TPU extraction layer through each of the penetration holes.

10. The method for forming an insulating structure based on an electrocoagulating wire according to claim 9, characterized in that, The porosity and / or pore size of the penetration holes on the distal end face of the alloy core wire located in the electrocoagulation zone gradually increase from the geometric center toward the periphery; and / or, The hardness of the TPU impregnation layer is 70A~90A; and / or, The flexural modulus of the TPU impregnation layer is 20MPa~35MPa; and / or, The Poisson's ratio of the TPU extraction layer is 0.45~0.5; The length of the electrocoagulation zone is 1mm to 5mm; and / or, The diameter of the distal ball head is 0.2mm~0.3mm; and / or, Before the step of exposing the head end of the alloy core wire, and after the step of performing a tear-away heat-shrinkable leveling treatment on the TPU impregnation layer, the method for forming the insulation structure based on the electrocoagulated conductor wire further includes the following steps: The TPU extraction layer is subjected to a functional coating adhesion treatment so that a hydrophilic coating is attached to at least the surface of the TPU extraction layer, and the hydrophilic coating is attached to the distal end of the PET heat shrink tubing.

11. The method for forming an insulating structure based on an electrocoagulating wire according to claim 9 or 10, characterized in that, The pore size of the penetration pores in the TPU extraction layer located in the electrocoagulation zone satisfies the following condition: ； Where θ is the angle formed by the intersection of the straight line connecting the point on the arc surface of the distal ball head to the center of the distal ball head and the axis; d(θ) is the diameter of the penetration hole; t0 is the thickness of the TPU extraction layer corresponding to that point; k is 0.08~0.18; δ is 0.1~0.

3.

12. The method for forming an insulating structure based on an electrocoagulating wire according to claim 11, characterized in that, The porosity of the penetration pores in the TPU extraction layer located in the electrocoagulation zone satisfies the following condition: ； ； Where θ is the angle formed by the intersection of the straight line connecting the points on the arc surface of the distal ball head to the center of the distal ball head and the axis; ρ(θ) is the porosity of the infiltration hole; ρ max The maximum allowable opening ratio is 20%~30%; n0 is the top base density of 10%~20%; β is 0.5~0.

8.

13. The method for forming an insulating structure based on an electrocoagulating wire according to claim 9 or 10, characterized in that, The porosity and pore size of the penetration pores in the TPU extraction layer located in the electrocoagulation zone are shown below: 。 14. An insulation structure based on an electrocoagulating conductor wire, characterized in that, It is formed by the molding method of the insulating structure based on electrocoagulation wire as described in any one of claims 1 to 13.

15. An electrocoagulation wire, characterized in that, It includes a functional coating and the insulating structure based on electrocoating wire as described in claim 14, wherein the functional coating is attached together to the TPU impregnation layer, the PET heat shrink tubing and the proximal end of the alloy core wire.

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