Metal wire, catheter and manufacturing method of metal wire

Abstract

The invention discloses a metal wire, a catheter and a manufacturing method of the metal wire, and belongs to the technical field of medical instruments. The metal wire comprises a plurality of necking sections which are arranged at intervals in the length direction of the metal wire, a widened section is formed between every two adjacent necking sections, so that the necking sections and the widened sections are sequentially and alternately arranged in the length direction of the metal wire, and the cross sectional area of the necking sections is smaller than that of the widened sections; the widened section is provided with a through hole. The multiple necking sections and the multiple widening sections are sequentially and alternately arranged in the length direction of the metal wire, the cross sectional area of the necking sections is smaller than that of the widening sections, the necking sections have certain supporting force and flexibility, the widening sections with the through holes are arranged, the through holes provide deformation space for the metal wire, the flexibility of the widening sections is improved, and the service life of the widening sections is prolonged. A plurality of flexible areas with low local rigidity are formed, and the necking sections and the widened sections with the through holes are combined, so that the metal wire has flexibility and supporting force.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, and in particular to a metal wire, a catheter, and a method for manufacturing the metal wire. Background Technology

[0002] In neurointerventional and cardiovascular interventional procedures, catheters typically require good delivery capability, torque transmission, and distal compliance simultaneously. This means distal compliance, allowing for bending to avoid damage to fragile vessels, and proximal support and delivery to ensure operative control. To enhance mechanical performance, a reinforcing layer formed by braided or spring-loaded metal wire is often placed between the inner liner and outer sheath of the catheter. In related technologies, metal wires are categorized as round wires (circular cross-section), flat wires (rectangular cross-section), and spring-loaded wires. Round wire braiding offers good compliance but insufficient circumferential support; flat wire braiding provides strong circumferential support but is generally stiff, lacking flexibility and resulting in poor distal passage; spring-loaded wires offer high compliance, but the reinforcing layer is prone to buckling and kinking during small-radius bends, leading to localized stress concentration, affecting catheter delivery capability, and providing insufficient overall support. Therefore, the reinforcing layer formed by metal wires in some technologies still falls short in balancing compliance and support, making it difficult for catheters with this reinforcement layer to achieve both delivery capability and compliance. Summary of the Invention

[0003] The purpose of this invention is to provide a metal wire, a conduit, and a method for manufacturing the metal wire, wherein the metal wire combines flexibility and support, and the conduit combines pushability and flexibility.

[0004] To achieve this objective, the present invention adopts the following technical solution:

[0005] A metal wire includes a plurality of necked sections spaced apart along its length, with a widening section formed between adjacent necked sections, such that the plurality of necked sections and the plurality of widening sections are alternately arranged in sequence along the length of the metal wire, wherein the cross-sectional area of ​​the necked sections is smaller than the cross-sectional area of ​​the widening sections; and the widening sections are provided with through holes.

[0006] In some embodiments, the cross-section of the wire is rectangular or circular, and the ratio of the minimum width of the necking section to the maximum width of the widening section ranges from 0.2 to 0.8.

[0007] In some embodiments, the through hole includes a first elongated hole that penetrates along the thickness direction or radial direction of the metal wire and extends along the length direction of the metal wire.

[0008] In some embodiments, the through hole further comprises a second long slot, the first long slot is located at the middle of the widened section along the width direction or the radial direction, and the second long slot is arranged at the side of the first long slot along the width direction or the radial direction of the metal wire.

[0009] In some embodiments, the outer side of the widened section is provided with a first recessed groove; and / or, the hole wall of the first long slot is provided with a second recessed groove, the second recessed groove extends along the depth direction of the first long slot.

[0010] In some embodiments, the cross section of the metal wire is rectangular, the thickness is 0.01mm-0.10mm, and the width is 0.08mm-0.30mm; or, the cross section of the metal wire is circular, and the diameter of the metal wire is 0.02mm-0.10mm.

[0011] In some embodiments, at least part of the necked section is provided with a hole.

[0012] In some embodiments, the cross section shape of the hole is circular or long rounded rectangular, the maximum dimension of the hole along the length direction of the metal wire is 1-6 times the diameter of the widened section, and the maximum dimension of the hole along the radial direction of the metal wire is 0.6-2 times the diameter of the widened section; or, the maximum dimension of the hole (160) along the length direction of the metal wire is 1-6 times the width of the widened section, and the maximum dimension of the hole along the width direction of the metal wire is 0.6-2 times the width of the widened section.

[0013] In some embodiments, the hole edge at both ends of the hole is provided with a rounded corner, and the radius of the rounded corner is greater than or equal to 0.2 times the thickness or diameter of the metal wire.

[0014] In some embodiments, the plurality of necked sections are evenly arranged, and the length of the widened section ranges from 0.5mm to 5.0mm.

[0015] A catheter comprising an inner liner, a reinforcing layer and an outer cover layer arranged from inside to outside, the reinforcing layer is formed by the metal wire through the spring winding or braiding according to any one of the above.

[0016] In some embodiments, when the reinforcing layer is formed by braiding the metal wire, the braiding angle ranges from 20° to 110°, and the angle of the braiding angle at the proximal end of the catheter is not greater than the angle of the braiding angle at the distal end of the catheter; or, when the reinforcing layer is formed by the spring winding of the metal wire, the pitch ranges from 0.08mm to 1.5mm.

[0017] In some embodiments, the reinforcing layer comprises a first region arranged at a distal end of the catheter and a second region arranged at a proximal end, the wire comprises a first portion and a second portion, the first portion is arranged at the first region, and the second portion is arranged at the second region, only the first portion is provided with the necking section and the through hole.

[0018] In some embodiments, all the necking sections are provided with the through hole; or, the first region comprises a distal end part and an intermediate part, the intermediate part is arranged between the distal end part and the second region, the first portion comprises a first section and a second section, the first section is arranged at the distal end part, and the second section is arranged at the intermediate part, only the necking section of the first section is provided with the through hole.

[0019] A manufacturing method of the wire according to any one of the above, comprising:

[0020] The necking section and the through hole are formed by laser micro-machining, chemical etching or micro-stamping.

[0021] The transition zone between the edge of the through hole and the transition between the necking section and the widened section is polished.

[0022] The beneficial effects of the present application are:

[0023] The wire, the catheter and the manufacturing method of the wire provided by the present application, by arranging the necking section on the wire, and arranging the widened section between adjacent necking sections, so that the plurality of necking sections and the plurality of widened sections are arranged alternately in the length direction of the wire, the cross-sectional area of the necking section is smaller than that of the widened section, i.e. a plurality of narrowed structures with reduced cross-sectional area are arranged in the length direction of the wire, by reducing the cross-sectional area, the necking section has a certain supporting force and flexibility; by arranging the widened section with the through hole, the wire has sufficient cross-sectional area, which can ensure the coverage when used in the catheter, the through hole provides deformation space for the wire, which can improve the flexibility of the widened section, and form a plurality of flexible regions with low local rigidity. By combining the necking section and the widened section with the through hole, the wire has both flexibility and supporting force.

[0024] When the wire is used to form the reinforcing layer of the catheter by braiding or coiling, the catheter is bent or pulled, the through hole enables the widened section to deform, which improves the flexibility of the catheter; since the wire has a certain supporting force, the catheter also has a certain supporting force; the through hole arranged in the widened section improves the deformation ability, and has extensibility when the catheter is pulled, so that the catheter can adapt to the length change of the blood vessel during the pushing process, and reduce the folding; when the catheter is bent, the stress can be released locally by the arrangement of the necking section and the through hole, and stress concentration does not occur, so that the catheter has the pushing property. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1is a schematic view of a first metal wire provided by the embodiment of the present application;

[0026] Figure 2 is a schematic view of a second metal wire provided by the embodiment of the present application;

[0027] Figure 3 is a schematic view of a third metal wire provided by the embodiment of the present application;

[0028] Figure 4 is a schematic view of a fourth metal wire provided by the embodiment of the present application;

[0029] Figure 5 is a schematic view of a catheter provided by the embodiment of the present application;

[0030] Figure 6 is a schematic view of a first area reinforcing layer of a catheter formed by warp knitting of metal wires provided by the embodiment of the present application;

[0031] Figure 7 is a schematic view of a second area reinforcing layer of a catheter formed by warp knitting of metal wires provided by the embodiment of the present application;

[0032] Figure 8 is a schematic view of a first area reinforcing layer of a catheter formed by spring winding of metal wires provided by the embodiment of the present application;

[0033] Figure 9 is a schematic view of a second area reinforcing layer of a catheter formed by spring winding of metal wires provided by the embodiment of the present application.

[0034] in the figure:

[0035] 100, metal wire; 101, first part; 102, second part; 110, necking section; 120, widening section; 130, through hole; 131, first long slot; 132, second long slot; 140, first recessed groove; 150, second recessed groove; 160, hole;

[0036] 200, catheter; 201, reinforcing layer; 202, inner liner; 203, outer cover; 210, first area; 220, second area. DETAILED DESCRIPTION

[0037] In order to make the technical problems solved by the present application, the technical solutions adopted and the technical effects reached more clear, the technical solutions of the embodiments of the present application will be further described in detail below with reference to the drawings. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all the other embodiments obtained by those skilled in the art without creative efforts fall within the scope of the present application.

[0038] In the description of the present application, unless explicitly defined and limited otherwise, the terms "connected", "connected", "fixed" should be understood broadly, for example, it can be fixedly connected, or detachably connected, or integrated; it can be mechanically connected, or electrically connected; it can be directly connected, or indirectly connected through an intermediate medium; it can be the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0039] In the present application, unless explicitly defined and limited otherwise, the first feature "on" or "under" the second feature can include that the first and second features are in direct contact, or that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, the first feature "on", "above" and "above" the second feature includes that the first feature is directly above and obliquely above the second feature, or only indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature "under", "below" and "below" the second feature includes that the first feature is directly below and obliquely below the second feature, or only indicates that the horizontal height of the first feature is less than that of the second feature.

[0040] As shown in Figures 1-4 The present embodiment provides a metal wire, the metal wire 100 includes a plurality of necking segments 110 arranged at intervals along the length direction of the metal wire, a plurality of widened segments 120 are formed between adjacent necking segments 110, so that the plurality of necking segments 110 and the plurality of widened segments 120 are arranged alternately in sequence in the length direction of the metal wire 100, the cross-sectional area of the necking segment 110 is smaller than the cross-sectional area of the widened segment 120; the widened segment 120 is provided with a through hole 130.

[0041] The necking segments 110 and the widening segments 120 are alternately arranged in the length direction of the metal wire 100, the cross-sectional area of the necking segment 110 is smaller than that of the widening segment 120, that is, a plurality of narrowed structures with reduced cross-sectional area are arranged in the length direction of the metal wire 100, and the necking segment 110 has a certain supporting force and flexibility by reducing the cross-sectional area; the metal wire 100 has sufficient cross-sectional area by the arrangement of the widening segment 120 with the through hole 130, which can ensure the overall circumferential coverage when used in the catheter 200, the through hole 130 provides a deformation space for the deformation of the metal wire, which can improve the flexibility of the widening segment 120 and form a plurality of flexible areas with low local rigidity. The combination of the necking segment and the widening segment with the through hole makes the metal wire 100 have both flexibility and supporting force.

[0042] The necking segments 110 are uniformly arranged, and the length of the widening segment 120 ranges from 0.5 mm to 5.0 mm, that is, the necking segments 110 are periodically arranged along the length direction of the metal wire 100, and the interval period is 0.5 mm, 1.0 mm, 1.5 mm, 2.0 mm, 2.5 mm, 3.0 mm, 3.5 mm, 4 mm, 4.5 mm or 5.0 mm, etc. The longer the length of the widening segment 120 and the shorter the length of the necking segment 110, the better the flexibility, and vice versa. As shown in Figure 1 and Figure 2 As shown in Figure 1 , the length of the widening segment 120 is longer and the length of the necking segment 110 is shorter, Figure 2 , the length of the widening segment 120 and the length of the necking segment 110 are similar, which can be set according to the requirements.

[0043] As shown in Figure 3 , at least part of the necking segments 110 are provided with holes 160, which further weaken the local cross-sectional area, and the holes 160 provide a deformation space for the necking segments 110, making the position more easily bent or stretched, which can further increase the flexibility of the necking segments 110. Optionally, the holes 160 are arranged in the central region of the necking segments 110.

[0044] As shown in Figure 1 , the cross section of the metal wire 100 is rectangular or circular, the minimum width of the necking segment 110 is a, and the maximum width of the widening segment 120 is b, and the ratio of a and b ranges from 0.2 to 0.8, such as 0.2, 0.3, 0.4, 0.5, 0.6, 0.7 or 0.8, etc.

[0045] In an embodiment, the metal wire 100 has a rectangular cross section, i.e. the metal wire 100 is a flat wire, with a width of 0.08mm-0.30mm and a thickness of 0.01mm-0.10mm, the width and thickness can be matched arbitrarily, and the thickness is not greater than the width, for example, the width is 0.10mm and the thickness is 0.02mm. The necked section 110 is inwardly contracted along the width direction of the metal wire 100, and the middle part of the necked section 110 is rectangular, and the two ends are connected to the widened section 120 through a rounded corner, and the minimum width of the necked section 110 is the width of the rectangular middle part.

[0046] As shown in Figure 4 The through hole 130 includes a first long hole 131 and a second long hole 132, both of which penetrate along the thickness direction of the metal wire 100 and extend along the length direction of the metal wire 100. The first long hole 131 is located at the middle position of the widened section 120 along the width direction, and the second long hole 132 is arranged on the side of the first long hole 131 along the width direction of the metal wire 100, i.e. the first long hole 131 and the second long hole 132 are arranged in parallel along the width direction of the metal wire 100, and the lengths of the two are the same or different. The first long hole 131 can be provided with a second long hole 132 on one side, or can be provided with a second long hole 132 on both sides, and the two second long holes 132 on both sides can be arranged symmetrically or asymmetrically. The side of the first long hole 131 can have one second long hole 132 or multiple second long holes 132, and the multiple second long holes 132 can be arranged along the length direction of the metal wire 100 or along the width direction of the metal wire 100; the lengths of the second long holes 132 can be the same or different. Exemplarily, the second long hole 132 is provided with two second long holes 132, which are symmetrically arranged on both sides of the first long hole 131 along the width direction, or more second long holes 132 can be arranged, which are not limited. When only one first long hole 131 is arranged, the structure is simple, and when the first long hole 131 and the second long hole 132 are arranged at the same time, the flexibility is improved, and the stress concentration of the hole edge is reduced.

[0047] The cross-sectional shape of the hole 160 can be regular or irregular, and the cross-sectional shape of the hole 160 is circular or long-round rectangular, which prevents stress concentration. The maximum size of the hole 160 along the length direction of the metal wire 100 is 1-6 times the width of the widened section 120, that is, the maximum size of the hole 160 along the length direction of the metal wire 100 is 1-6 times the width of the widened section 120; the maximum size of the hole 160 along the width direction of the metal wire 100 is 0.6-2 times the width of the widened section 120, that is, the maximum size of the hole 160 along the width direction of the metal wire 100 is 0.6-2 times the width of the widened section 120, and all contour points on the hole 160 do not exceed the rectangular range with the side length of 1-6 times the width of the widened section 120 and 0.6-2 times the width of the widened section 120. Alternatively, the cross-sectional shape of the hole 160 is circular, and the diameter is the overlapping range size of 0.6-2 times the width of the widened section 120 and 1-6 times the width of the widened section 120; the cross-sectional shape of the hole 160 is long-round rectangular, and the total length including the round corner is 1-6 times the width of the widened section 120, and the total width including the round corner is 0.6-2 times the width of the widened section 120. The maximum size of the hole 160 along the length direction of the metal wire 100 is greater than or equal to the maximum size of the hole 160 along the width direction of the metal wire 100. Taking the long-round rectangular cross-sectional shape of the hole 160 as an example, the long side is arranged along the extension direction of the metal wire 100, which can provide additional extension space when subjected to tension.

[0048] The hole edge at both ends of the hole 160 is provided with a round corner, and the radius of the round corner is greater than or equal to 0.2 times the thickness of the metal wire 100, so as to reduce stress concentration. The round corner hole edge disperses stress and does not form a crack source, thereby avoiding fatigue fracture, thus improving the fatigue life. Tests show that no wire breakage occurs under 10 6 -10 7 times of bending cycles. Further, the safety of the catheter 200 in long-term clinical operation is ensured. The hole 160 reduces the weight of the metal wire 100, so that the weight of the catheter 200 is lighter, and the pushing / manipulation resistance of the operator is lower, and the hand feeling is better.

[0049] In an embodiment, the cross section of the metal wire 100 is circular, that is, the metal wire 100 is a round wire, and the diameter of the metal wire 100 is 0.02mm-0.10mm, such as 0.02mm, 0.04mm, 0.06mm, 0.08mm, 0.10mm, etc. The necked section 110 is inwardly contracted from both sides along the radial direction of the metal wire 100, and the middle part of the necked section 110 is a uniform structure, and the two ends are transitioned through a round corner to the widened section 120, and the width of the middle part is the minimum width of the necked section 110.

[0050] The through hole 130 includes a first long hole 131 and a second long hole 132, both of which pass through the metal wire 100 radially and extend along the length of the metal wire 100. The first long hole 131 is located at the middle of the widened section 120 in the radial direction, and the second long hole 132 is located on the side of the first long hole 131 in the radial direction of the metal wire 100. Two second long holes 132 are symmetrically arranged on both sides of the first long hole 131 in the radial direction, or more second long holes 132 can be arranged without limitation.

[0051] The cross-sectional shape of the hole 160 can be regular or irregular. Optionally, the cross-sectional shape of the hole 160 is circular or long-rectangular with rounded corners to prevent stress concentration. The maximum dimension of the hole 160 along the length of the metal wire 100 is 1-6 times the diameter of the widened section 120, and the maximum dimension of the hole 160 in the radial direction of the metal wire 100 is 0.6-2 times the diameter of the widened section 120. Optionally, the cross-sectional shape of the hole 160 is circular, and the diameter is within the overlapping range of 0.6-2 times the diameter of the widened section 120 and 1-6 times the diameter of the widened section 120; the cross-sectional shape of the hole 160 is long-rectangular with rounded corners, the total length including the rounded corners is 1-6 times the diameter of the widened section 120, and the total width including the rounded corners is 0.6-2 times the diameter of the widened section 120. The maximum dimension of the hole 160 along the length of the metal wire 100 is greater than or equal to the maximum dimension of the hole 160 in the radial direction of the metal wire 100.

[0052] The hole edge at both ends of the hole 160 is provided with a rounded corner, and the radius of the rounded corner is greater than or equal to 0.2 times the diameter of the metal wire 100.

[0053] As shown in Figure 4 The outer side of the widened section 120 is provided with a first recessed groove 140, and the hole wall of the first long hole 131 is provided with a second recessed groove 150 extending in the depth direction of the first long hole 131. The arrangement of the first recessed groove 140 and the second recessed groove 150 can further improve the flexibility of the widened section.

[0054] As shown in Figures 5-9As shown, the embodiment also provides a catheter 200, which comprises an inner liner 202, a reinforcing layer 201 and an outer cover 203 arranged from inside to outside, and the reinforcing layer 201 is formed by winding or weaving the metal wire 100 as described above. When the metal wire 100 is formed into the reinforcing layer 201 of the catheter 200 by weaving or winding, the catheter 200 is bent or pulled, and the widened section 120 is deformed in advance through the through hole 130 to improve the flexibility of the catheter 200; since the metal wire 100 has a certain supporting force, the catheter 200 has a certain supporting force; the through hole 130 provided in the widened section 120 improves the deformation ability and has the extension when the catheter 200 is pulled, so that the catheter 200 can adapt to the length change of the blood vessel during the pushing process and reduce the folding; when the catheter 200 is bent, the stress can be released locally through the setting of the necked section 110 and the through hole 130, and stress concentration does not occur, so that the catheter 200 has the pushing property.

[0055] As shown in Figure 6 and Figure 7 , in an embodiment, when the reinforcing layer 201 is formed by weaving the metal wire 100, the weaving angle ranges from 20° to 110°, and the angle of the weaving angle at the proximal end of the catheter 200 is not greater than the angle of the weaving angle at the distal end of the catheter 200; the holes 160 can be uniformly distributed or gradually distributed along the axial direction of the catheter 200 to form a gradient structure with a harder proximal end and a softer distal end. Figure 8 and Figure 9 , in an embodiment, when the reinforcing layer 201 is formed by winding the metal wire 100, the pitch ranges from 0.08mm to 1.5mm. The metal wire 100 is wound into a distal end ring at the distal end of the catheter 200 and a proximal end ring at the proximal end, the distal end ring can be provided with the hole 160 and the necked section 110, and the proximal end ring keeps the full cross-section without holes to reduce the risk of distal end folding and improve flexibility.

[0056] The reinforcing layer 201 comprises a first area 210 provided at the distal end of the catheter 200 and a second area 220 provided at the proximal end, as shown in Figure 5As shown, the length of the first region 210 is L1, the length of the second region 220 is L2, the metal wire 100 comprises a first part 101 and a second part 102, the first part 101 is arranged in the first region 210, the second part 102 is arranged in the second region 220, only the first part 101 is provided with the necked section 110 and the through hole 130, so that the distal end of the catheter 200 is softer and the proximal end support is better. In an embodiment, all the necked sections 110 are provided with the hole 160, so that the first region 210 as a whole has uniform flexibility. In an embodiment, the first region 210 comprises a distal end part and an intermediate part, the intermediate part is arranged between the distal end part and the second region 220, the first part 101 comprises a first section and a second section, the first section is arranged in the distal end part, the second section is arranged in the intermediate part, only the necked section 110 of the first section is provided with the hole 160, because the first section is provided with the necked section 110 and the hole 160 at the same time, the flexibility is the best, the second section is provided with the necked section 110 but does not have the hole 160, so the flexibility is the second, the second part 102 does not have the necked section 110, the through hole 130 and the hole 160, so the flexibility is the worst, so that the flexibility of the distal end part, the intermediate part and the second region 220 on the catheter 200 is improved in turn, forming a gradient structure that the proximal end is harder, the intermediate part is softer, and the distal end is softer.

[0057] Optionally, the distal end part of the first part 101, the intermediate part of the first part 101 and the second part 102 are an integral structure or a split structure, which is not limited.

[0058] In one embodiment, the inner liner 202 of the catheter 200 is a PTFE tube with a thickness of about 0.07 mm and an inner diameter of 1.80 mm; the reinforcing layer 201 is formed by braiding 32 metal wires 100 made of nickel-titanium material, the metal wire 100 is a flat wire with a thickness of 0.035 mm, a maximum width of 0.18 mm, and a minimum width of 0.08 mm, the necked section 110 is provided with a hole 160, the maximum size of the hole 160 along the length direction of the metal wire 100 is 0.15 mm, the maximum size along the width direction is 0.06 mm, and the hole edge has a round corner with a radius of about 0.02 mm, the length of the widened section 120 is 0.8 mm; the braiding angle at the proximal end is 35°, the braiding angle at the distal end is 55°, and the degrees between the braiding angle at the distal end and the braiding angle at the proximal end are arranged from large to small; the outer cover 203 is Pebax with a Shore hardness ranging from 55D to 72D and a thickness of about 0.12 mm. The outer diameter of the catheter 200 is about 2.1 mm, the inner diameter is 1.8 mm, and the wall thickness is 0.15 mm. Compared with the control catheter (using a flat wire braiding layer with an equal cross section), the minimum non-kinking bending radius of the catheter 200 of the embodiment is reduced by about 30% (from 12 mm to about 8 mm); under a 5N axial tensile load, the axial elongation rate of the catheter 200 is increased by about 50% (from 1.0% to 1.5%); and in the radial compression test, the anti-collapse ability is maintained at more than 90% of that of the control catheter.

[0059] In another embodiment, the inner liner 202 of the catheter 200 is a PTFE tube with a thickness of 0.08 mm and an inner diameter of 2.20 mm; the reinforcing layer 201 is formed by coiling a spring with metal wires 100 made of stainless steel, the metal wire 100 is a flat wire with a thickness of 0.05 mm and a width of 0.20 mm, and the necking ratio is about 0.5; five turns at the distal end are provided with necking and holes 160, the maximum size of the hole 160 along the length direction of the metal wire 100 is 0.25 mm, the maximum size along the width direction is 0.08 mm, and the length of the widened section 120 is 1.0 mm; the proximal end is kept full-section and non-hole, and the middle section is provided with only the necked section 110 without the hole 160; the coiling pitch of the spring is 0.6 mm; the outer cover 203 is made of Pebax material, and the Shore hardness thereof is designed in a gradient from 72D to 55D from the proximal end to the distal end, and the thickness is 0.15 mm-0.20 mm. The outer diameter of the catheter 200 is about 3.4 mm, the inner diameter is 2.6 mm, and the total wall thickness is 0.4 mm. In the simulated 3 mm radius bending pipe test, the proportion of kinking of the control coiled spring catheter is about 30%, while the catheter of the embodiment does not kink; in the three-point bending test, the bending stiffness of the distal end 50 mm section is reduced by about 35%, and the proximal end stiffness is maintained at more than 95% of that of the control; under the condition of negative pressure suction (-80 kPa), the catheter 200 does not collapse continuously, and the recovery rate is ≥95%.

[0060] In yet another embodiment, the inner liner 202 of the catheter 200 is made of PTFE tube with a thickness of 0.06 mm and an inner diameter of 1.70 mm; the proximal end of the reinforcing layer 201 is knitted with non-porous nickel-titanium flat wire, the middle section is knitted with flat wire with necking but without hole 160, and the distal end is knitted with flat wire with necking and hole 160; the number of knitted wires is 32, the thickness of the flat wire is 0.03 mm, the width of the flat wire is 0.16 mm, the maximum size of the hole 160 along the length direction of the metal wire 100 is 0.12 mm, and the maximum size along the width direction is 0.05 mm; the outer cover 203 is made of Pebax material, and the Shore hardness thereof gradually decreases from 63D to 40D from the proximal end to the distal end, and the thickness thereof is 0.10 mm. The outer diameter of the catheter 200 is 2.0 mm, the inner diameter is 1.7 mm, and the wall thickness is 0.15 mm. The gradual arrangement realizes the performance distribution of "rigid proximal end and soft distal end", that is, the proximal end EI (i.e. bending stiffness) remains 100% of that of the control catheter; the middle section EI decreases by about 20%; the distal end EI decreases by about 40%; in the simulated blood vessel passing test, the distal end flexibility is obviously improved, and the control catheter can smoothly pass through the curved model blood vessel with a minimum diameter of 2 mm, while the control catheter appears to be stuck.

[0061] By using the above metal wire 100, the catheter 200 has the following advantages: first, the flexibility is improved; when the catheter 200 is bent, ordinary flat wires are difficult to bend due to their large cross section; the metal wire 100 first buckles at the necking section 110 and the hole 160, and the bending is distributed on multiple sections, so that the catheter 200 as a whole is softer and can pass through a curved blood vessel with a smaller radius. Second, the axial elongation is controllable; the metal wire 100 allows a small amount of opening at the hole 160 area, which is equivalent to a "controllable extension unit", so that the catheter 200 can adapt to the length change of the blood vessel during pushing and reduce the folding. Third, the soft and hard gradient is controllable; by arranging more holes 160 and necking sections 110 at the distal end, necking sections 110 without holes 160 at the middle section, and no holes 160 and no necking sections 110 at the proximal end, a rigid-flexible transition is formed, so that the proximal end maintains the supporting force and pushability, the distal end is soft to enter the fine blood vessels, and the blood vessel damage is reduced. Fourth, the anti-folding performance is improved; the hole 160 and the necking section 110 can release stress locally and will not concentrate at a single point, so that the catheter 200 is not easy to fold when bending at a small radius.

[0062] The embodiment also provides a manufacturing method of the metal wire 100 as described above, which comprises:

[0063] S100, forming the necking section 110 and the through hole 130 by laser micro machining, chemical etching or micro punching; when the necking section 110 is provided with the hole 160, the hole 160 is also machined at the same time.

[0064] S200, polishing the edge of the through hole 130 and the transition zone between the necked section 110 and the widened section 120, the polishing method can be electro-polishing or chemical polishing, and the surface roughness after polishing is required to be less than or equal to 0.8 μm.

[0065] All technical features such as the necked section 110, the through hole 130 and the hole 160 are processed by step S100 at one time, and then surface treatment is performed, so that the number of processing steps is reduced, the efficiency is high, and the processing cost is reduced. Specifically, laser micro-processing has the advantages of high precision, high flexibility and wide material adaptation, and solves the problems of complex microstructure, non-metallic material and small batch customization; chemical etching has the advantages of large area uniformity, ultra-thin material adaptation and low cost batch production, and solves the problems of two-dimensional complex pattern, ultra-thin sheet and large batch replication; micro-punching has the advantages of high efficiency, low cost and high rigidity, and solves the problems of metal thin material, standardized structure and ultra-large batch production. The above three processing methods are prior art, and can be selected according to their respective advantages.

[0066] Further, if the material of the metal wire 100 is nickel-titanium alloy, step S200 further includes:

[0067] S300, stress relief or shaping heat treatment is performed on the metal wire 100, which is specifically described with reference to the prior art, and will not be repeated here.

[0068] Obviously, the above embodiments of the present application are only examples for clearly illustrating the present application, and are not intended to limit the embodiments of the present application. Based on the above description, other different forms of changes or variations can be made by those skilled in the art. Here, all the embodiments are not required to be exhausted. Any modification, equivalent replacement and improvement made within the spirit and principle of the present application shall be included in the protection scope of the claims of the present application.

Claims

1. A wire, characterized in that The metal wire (100) comprises a plurality of necked segments (110) arranged at intervals along the length direction of the metal wire (100), a plurality of widened segments (120) formed between adjacent necked segments (110), and a plurality of through holes (130) formed in the widened segments (120).

2. The wire of claim 1, wherein The cross section of the metal wire (100) is rectangular or circular, and the ratio of the minimum width of the necked segment (110) to the maximum width of the widened segment (120) is in the range of 0.2-0.

8.

3. The wire of claim 2, wherein The through hole (130) comprises a first long slot (131) extending through the metal wire (100) in the thickness direction or radial direction and extending along the length direction of the metal wire (100).

4. The wire of claim 3, wherein The through hole (130) further comprises a second long slot (132) arranged on the side of the first long slot (131) in the width direction or radial direction of the metal wire (100).

5. The wire of claim 3, wherein The widened segment (120) is provided with a first recessed groove (140) on the outer side, and / or the hole wall of the first long slot (131) is provided with a second recessed groove (150) extending in the depth direction of the first long slot (131).

6. The wire of claim 2, wherein The cross section of the metal wire (100) is rectangular, the thickness is in the range of 0.01mm-0.10mm, and the width is in the range of 0.08mm-0.30mm; or the cross section of the metal wire (100) is circular, and the diameter of the metal wire (100) is in the range of 0.02mm-0.10mm.

7. The wire of claim 1, wherein At least part of the necked segments (110) are provided with holes (160).

8. The wire of claim 7, wherein The cross section of the hole (160) is circular or long rounded rectangular, the maximum dimension of the hole (160) in the length direction of the metal wire (100) is 1-6 times the diameter of the widened segment (120), and the maximum dimension of the hole (160) in the radial direction of the metal wire (100) is 0.6-2 times the diameter of the widened segment (120); or the maximum dimension of the hole (160) in the length direction of the metal wire (100) is 1-6 times the width of the widened segment (120), and the maximum dimension of the hole (160) in the width direction of the metal wire (100) is 0.6-2 times the width of the widened segment (120).

9. The wire of claim 7, wherein The hole edge at both ends of the hole (160) is provided with a rounded corner, and the radius of the rounded corner is greater than or equal to 0.2 times the thickness or diameter of the metal wire (100).

10. The wire of claim 1, wherein The plurality of necked segments (110) are uniformly arranged, and the length of the widened segment (120) is in the range of 0.5mm-5.0mm.

11. A catheter, characterized by The catheter (200) comprises an inner liner (202), a reinforcing layer (201) and an outer cover (203) arranged from inside to outside, wherein the reinforcing layer (201) is formed by winding or weaving the metal wire (100) according to any one of claims 1-10.

12. The catheter of claim 11, wherein, When the reinforcing layer (201) is formed by weaving the metal wire (100), the weaving angle ranges from 20° to 110°, and the angle of the weaving angle at the proximal end of the catheter (200) is not greater than the angle of the weaving angle at the distal end of the catheter (200); or, when the reinforcing layer (201) is formed by winding the metal wire (100), the pitch ranges from 0.08mm to 1.5mm.

13. The catheter of claim 11, wherein, The reinforcing layer (201) comprises a first region (210) arranged at the distal end of the catheter (200) and a second region (220) arranged at the proximal end, the metal wire (100) comprises a first part (101) and a second part (102), the first part (101) is arranged at the first region (210), and the second part (102) is arranged at the second region (220), only the first part (101) is provided with a necking segment (110) and a through hole (130).

14. The catheter of claim 13, wherein, All necking segments (110) are provided with holes (160); or, the first region (210) comprises a distal end part and an intermediate part, the intermediate part is arranged between the distal end part and the second region (220), the first part (101) comprises a first segment and a second segment, the first segment is arranged at the distal end part, and the second segment is arranged at the intermediate part, only the necking segment (110) of the first segment is provided with the hole (160).

15. A method of manufacturing a wire as claimed in any one of claims 1-10, characterized in that, The catheter (200) comprises: The necking segment (110) and the through hole (130) are formed by laser micromachining, chemical etching or micro-punching; The edges of the through hole (130) and the transition zones between the necking segment (110) and the widened segment (120) are polished.

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