catheter

Abstract

This catheter includes at least a cylindrical reinforcing member (2) that includes a braided body formed from a woven mesh of a plurality of first strands extending in a first direction and a plurality of second strands extending in a second direction, and extends in the stretching direction. The plurality of first strands have a melting point that is more than 500°C higher than the melting point of the plurality of second strands. At one or both of the opposite ends of the reinforcing member (2) in the stretching direction, bonding parts (5[n], 5[n+1]) are formed at some of a plurality of intersections at which the plurality of first and second strands are intersecting. The bonding parts (5 [n]) bond the intersecting first strands (3[n]) and second strands (4[n]) by allowing the first strands (3[n]) and second strands (4[n]) at their contact parts to form alloys.

Description

[Technical field]

[0001] The present invention relates to a catheter. [Background technology]

[0002] A catheter is required to have good pushability because the tip must be properly delivered to the site in the blood vessel to be treated. Therefore, various catheters having a reinforcing structure for realizing such characteristics have been proposed. Patent Document 1 discloses a catheter having a metal mesh made of stainless steel (SUS) wires as a reinforcing structure. In this catheter, a laser beam is irradiated to the intersections of a first set of wires and a second set of wires of the metal mesh to weld them. Next, a laser beam is irradiated to the metal mesh along the cutting line to cut the metal mesh. This processing method makes the end of the metal mesh less likely to unravel. Note that, during welding by irradiation of a laser beam, it is preferable that the first set of wires and the second set of wires are melted and alloyed at their respective contact portions to maintain the strength of the welded portion. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2005-230318 A Summary of the Invention

[0004] In order to increase the strength of the reinforcing structure, a metal mesh made of a plurality of wires of different materials may be used. An example will be given in which a laser beam is irradiated based on the above processing method to each of two wires made of materials with a large difference in melting point. When the laser beam is irradiated with an intensity required to melt the wire (referred to as the first wire) with a relatively higher melting point among the two wires, the wire (referred to as the second wire) with a relatively lower melting point among the two wires may melt, and the second wire may melt and cut. On the other hand, when the laser beam is irradiated with an intensity required to melt the second wire, the first wire may not melt. That is, in either case, the first and second wires are not melted and alloyed at the contact portion, so there is a problem that the strength of the welded portion may not be maintained.

[0005] An object of the present invention is to provide a catheter that can prevent the ends of the metal mesh from unraveling even when multiple wires with different melting points are used.

[0006] A catheter according to a first aspect of the present invention comprises a braided body in which a plurality of first wires extending in a first direction and a plurality of second wires extending in a second direction intersecting the first direction are woven in a network pattern, and at least a tubular reinforcing member extending in the extension direction is provided, wherein the melting point of the plurality of first wires is at least 500°C higher than the melting point of the plurality of second wires, and at least one of both ends in the extension direction of the reinforcing member has a joint formed at some of a plurality of intersections where the plurality of first wires and the plurality of second wires intersect, and the joint is formed by joining first crossing wires and second crossing wires, which are the plurality of first wires and the plurality of second wires that intersect each other at some of the intersections, and alloying the contact portions of the first crossing wires and the second crossing wires.

[0007] In the catheter, the first cross wire and the second cross wire are alloyed at their contact portions and joined to form a joint. Therefore, even when a braided body made of a plurality of first wires and a plurality of second wires having different melting points is used as the reinforcing member, the catheter can make the end portion in the extension direction of the reinforcing member less likely to unravel.

[0008] In the first aspect, at least one of both ends in the extension direction of each of the plurality of first wires and the plurality of second wires may have a curved portion curved with respect to the extension direction. Even in a state in which each of the plurality of first wires and the plurality of second wires is curved at the curved portion, the catheter can maintain a state in which each of the plurality of first wires and the plurality of second wires is joined to each other by alloying at the joint.

[0009] In the first aspect, a second tip portion of the second cross wire, which is located closer to the tip than the joint portion, may be wound around the first cross wire. In this case, the catheter can further firmly join the first cross wire and the second cross wire.

[0010] In the first embodiment, the catheter may include an inner layer tube having a cylindrical shape centered on the central axis of the reinforcing member and disposed in the lumen of the reinforcing member, and an outer layer tube having a cylindrical shape centered on the central axis and covering the reinforcing member from the outside. The inner layer tube can prevent a wire or the like from getting caught on the reinforcing member when the wire passes through the lumen of the reinforcing member. Furthermore, the outer layer tube can prevent the reinforcing member from being exposed. Therefore, the catheter can reduce the possibility that the reinforcing member will get caught on a blood vessel when the catheter passes through the blood vessel.

[0011] In the first embodiment, the inner tube may have a higher light transmittance than the outer tube. When a laser beam is applied to heat and join the first and second wires, the inner tube is prevented from absorbing the laser beam and generating heat. This reduces the possibility that the inner tube will melt or break due to heat generated by the catheter.

[0012] In the first embodiment, the material of the inner layer tube may be polytetrafluoroethylene, which makes it easy to realize an inner layer tube with high transmittance.

[0013] In the first aspect, the first crossing wire may be disposed on one side of the second crossing wire in a third direction perpendicular to the first direction and the second direction. In this case, the first crossing wire and the second crossing wire can be easily joined by irradiating a laser beam from one side of the third direction. When forming a joint by irradiating a laser beam, more energy of the laser beam can be applied to the first wire having a high melting point to melt the first wire. Moreover, the second wire can be melted and cut by suppressing the application of energy of the laser beam to the second wire having a low melting point.

[0014] In the first aspect, one of the plurality of first wires and the plurality of second wires may have a circular cross-sectional shape, and the other of the plurality of first wires and the plurality of second wires may have a rectangular cross-sectional shape. Also, in the first aspect, the plurality of first wires may have a circular cross-sectional shape, and the plurality of second wires may have a rectangular cross-sectional shape. In this case, the catheter can easily realize the step of alloying the first crossing wires and the second crossing wires at their contact portions to form joints.

[0015] In the first embodiment, the first wires may have a larger absorption coefficient than the second wires. In this case, even if the first wires and the second wires are joined by irradiating the laser light once, the first wires and the second wires can be appropriately melted and alloyed to be joined to each other.

[0016] In the first embodiment, the composition of the second crossing wires excluding the joint may be the same regardless of the distance from the joint. In this case, the catheter can stably maintain the composition of the second wires, thereby maintaining the strength of the braid.

[0017] In the first embodiment, the first wires may be made of tungsten, and the second wires may be made of stainless steel. In this case, the catheter can be easily pushed into the body by the braid. Furthermore, since tungsten has excellent radiation shielding properties, the position of the catheter in the body can be easily confirmed by irradiating it with radiation.

[0018] A method for producing a catheter according to a second aspect of the present invention includes a braided body in which a plurality of first wires extending in a first direction and a plurality of second wires extending in a second direction intersecting the first direction are woven in a net shape, the braided body including at least a tubular reinforcing member extending in the extension direction; The melting point of the first wires is 500° C. or more higher than the melting point of the second wires; a joint is formed at a joint intersection that is a part of a plurality of intersections where the plurality of first wires and the plurality of second wires intersect at at least one of both end portions in the extension direction of the reinforcing member, The joint is The first wire [n] and the second wire [n] that intersect with each other at a joint intersection [n] among the plurality of intersections are joined by alloying at their respective contact portions, At the joint intersection point [n], the first wire [n] is disposed on one side of the second wire [n] in a third direction perpendicular to the first direction and the second direction. A method for producing a catheter, comprising the steps of: a first irradiation step of irradiating a laser beam from one side in the third direction to a first irradiation region [n] including at least a part of a joint region [n] where the first wire [n] and the second wire [n] overlap with each other when the braided body is viewed from one side in the third direction, and a part of the second wire [n] that does not overlap with the first wire [n], thereby alloying and joining the first wire [n] and the second wire [n] at the joint intersection [n] and melting a part of the second wire [n] on one side in the second direction with respect to the joint intersection [n]; a second irradiation step of cutting the first wire [n] at the position of the second irradiation region [n] by irradiating a laser beam from one side in the third direction to a second irradiation region [n] of the first wire [n] that is spaced from the joint intersection [n] on one side in the first direction after the irradiation of the laser beam in the first irradiation step; The present invention is characterized by comprising:

[0019] The laser light irradiated in the first irradiation step first heats and melts a part of the first wire [n], then heats and melts the second wire [n], and simultaneously alloys and joins the melted first wire [n] and the second wire "n". The laser light irradiated in the second irradiation step heats and melts the first wire [n]. This makes it difficult for at least one of the extension directions of the reinforcing member to melt due to the joint.

[0020] In the above manufacturing method, by irradiating the laser light once in the first irradiation step, the first wire [n] and the second wire [n] are joined by alloying and the second wire [n] is melted at the same time. This reduces the possibility that the accuracy of the positional relationship between the position of the joint and the melting position of the second wire decreases. In addition, the energy of the laser light is first applied to the first wire [n], and the remaining energy is applied to the second wire [n]. Therefore, even if the melting point of the first wire is 500°C or more higher than the melting point of the second wire, the joining of the first wire [n] and the second wire [n] and the melting of the first wire [n] can be efficiently performed by irradiating the laser light once.

[0021] In a second embodiment, at least one of the first irradiation step and the second irradiation step is The energy imparted to the braid by irradiation with laser light may be varied over time.

[0022] In this case, heat transfer from the first wire and the second wire toward the vicinity of the laser light irradiated area can be suppressed, thereby preventing the first wire and the second wire from melting, evaporating, or disappearing near the laser light irradiated area.

[0023] In a second embodiment, at least one of the first irradiation step and the second irradiation step is a pre-irradiation step of irradiating with a laser beam having a relatively low intensity; a post-irradiation step of irradiating a laser beam having a relatively high intensity after the pre-irradiation step; The present invention may also include:

[0024] In this case, it is possible to more effectively prevent the first and second wires from melting, evaporating, or disappearing in the vicinity of the region irradiated with the laser light.

[0025] In a second embodiment, at least one of the first irradiation step and the second irradiation step is The laser light may be intermittently irradiated multiple times.

[0026] In this case, it is possible to more effectively prevent the first and second wires from melting, evaporating, or disappearing in the vicinity of the region irradiated with the laser light.

[0027] In the second aspect, among the plurality of intersections, at a first intersection where a first element wire [n+1] adjacent to the first element wire [n] on the other side in the second direction intersects with the second element wire [n], the first element wire [n+1] is disposed on one side in the third direction with respect to the second element wire [n], Among the multiple intersections, at a second intersection where the first wire [n] intersects with a second wire [n+1] adjacent to the second wire [n] on the other side of the second wire [n] in the first direction, the second wire [n+1] may be arranged on one side of the first wire [n] in the third direction.

[0028] When the catheter joins the first wire [n] and the second wire [n] at the joint node [n], the second wire [n+1] can prevent the first wire [n] from moving to one side in the third direction. Also, when the catheter joins the first wire [n] and the second wire [n] at the joint node [n], the first wire [n+1] can prevent the second wire [n] from moving to one side in the third direction.

[0029] In the second aspect, after the irradiation of the laser light in the second irradiation step, a first irradiation region [n+1] including at least a part of a joint region [n+1] where the first element wire [n+1] and the second element wire [n+1] overlap when the braid is viewed from one side in the third direction, and a part of the second element wire [n+1] that does not overlap with the first element wire [n+1], is irradiated with laser light from one side in the third direction at a joint intersection [n+1] where the first element wire [n+1] and the second element wire [n+1] intersect, thereby alloying and joining the first element wire [n+1] and the second element wire [n+1] at the joint intersection [n+1], and melting a part of the second element wire [n+1] on one side in the second direction with respect to the joint intersection [n+1]; a fourth irradiation step of cutting the first wire [n+1] at the position of the second irradiation region [n+1] by irradiating a laser beam from one side in the third direction to a second irradiation region [n+1] of the first wire [n+1] that is spaced from the joint intersection [n+1] on one side in the first direction, after the irradiation of the laser beam in the third irradiation step; The present invention may also include:

[0030] In this case, the first wire[n+1] and the second wire[n+1] can be joined and then melted down.

[0031] In the second aspect, the joint intersection point [n] and the joint intersection point [n+1] may be arranged side by side in the stretching direction.

[0032] In this case, the reinforcing member can be cut in a direction perpendicular to the stretching direction.

[0033] In the second embodiment, in the first irradiation step and the second irradiation step, The reinforcing member may be irradiated with laser light while an inert gas in a laminar flow state is being blown thereto.

[0034] In this case, it is possible to prevent the first wire and the second wire from being burned or oxidized due to laser irradiation.

[0035] In a second embodiment, the method further includes a previous step of arranging a cylindrical inner tube around a cylindrical metal wire extending in the extension direction, and arranging the metal wire and the inner tube in an inner cavity of the reinforcing member, In the first irradiation step and the second irradiation step, The braid of the reinforcing member prepared in the previous step is irradiated with laser light, The method may further include a post-step of disposing a cylindrical outer layer tube around the reinforcing member after the laser light irradiation in the second irradiation step.

[0036] In this case, a catheter having a reinforcing member, an inner layer tube, and an outer layer tube can be manufactured. In particular, by using a metal wire, a catheter having a thin inner layer tube can be easily manufactured. In addition, by using a metal wire, the laser light irradiated to the reinforcing member can be prevented from passing through the inner cavity of the reinforcing member and reaching the opposite side, thereby reducing the possibility that the reinforcing member on the opposite side will be melted by the laser light.

[0037] In the second embodiment, the inner tube may have a higher light transmittance than the outer tube.

[0038] In this case, the inner tube is prevented from generating heat due to absorption of the laser light, and therefore the possibility that the inner tube will melt or break due to heat generated by irradiation with the laser light, and that the first and second wires will melt and be joined at a location other than the joint, can be reduced.

[0039] In the second embodiment, the metal wire may have a thermal conductivity of 350 to 450 w / mK.

[0040] In other words, by using a material with high thermal conductivity among metal wires, thermal diffusion is promoted, so that local temperature increases in the metal wire can be suppressed by thermal diffusion, and therefore the possibility of the inner tube melting due to a temperature increase in the metal wire can be reduced. [Brief description of the drawings]

[0041] [Figure 1] FIG. 2 shows a catheter 1 and a connector 9. [Diagram 2] FIG. 1 shows a catheter 1. [Diagram 3] FIG. 2 is a diagram showing the reinforcing member 2 in an unfolded state. [Figure 4] FIG. 2 is an enlarged perspective view of a portion of the reinforcing member 2 in an unfolded state. [Diagram 5] FIG. 2 is a diagram showing the vicinity of the tip of the reinforcing member 2 in an unfolded state. [Figure 6] FIG. 6 is an enlarged perspective view of a portion of FIG. 5. [Figure 7] 1 is a photograph of a joint 5 of a reinforcing member 2. [Figure 8] 1 is a photograph of a cross section of joint 5[x]. [Figure 9] FIG. 1 is a schematic diagram showing a cross section of a joint formed by a conventional method. [Figure 10] 1 is a flowchart showing a method for manufacturing the catheter 1. [Figure 11] FIG. 2 is a diagram showing a long wire 10 prepared in a previous process. [Figure 12] FIG. 2 is an enlarged perspective view of a portion of the reinforcing member 2 in an expanded state during the manufacturing process of the catheter 1. [Figure 13] 13 is a diagram showing the vicinity of the joint intersection point Qc[n] as viewed from the first direction. [Figure 14A] FIG. 11 is a diagram showing a process in which a joint 5[n] is formed by irradiation with laser light. [Figure 14B] FIG. 11 is a diagram showing a process in which a joint 5[n] is formed by irradiation with laser light. [Figure 15A] FIG. 4 is an explanatory diagram for explaining an output pattern of a laser beam. [Figure 15B] FIG. 4 is an explanatory diagram for explaining an output pattern of a laser beam. [Figure 16A] 11A to 11C are diagrams illustrating a process in which a first wire 3[n] is melted by irradiation with laser light. [Figure 16B] 11A to 11C are diagrams illustrating a process in which a first wire 3[n] is melted by irradiation with laser light. [Figure 17A] FIG. 11 is a diagram showing a state when a first wire 3[n] is melted down. [Figure 17B] FIG. 11 is a diagram showing a state when a first wire 3[n] is melted down. [Figure 18] FIG. 13 is a diagram showing a later step of arranging an outer layer tube 7. [Figure 19A] 13 is an explanatory diagram for explaining an output pattern of a laser beam in a modified example. FIG. [Figure 19B] 13 is an explanatory diagram for explaining an output pattern of a laser beam in a modified example. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0042] <Overview of Catheter 1> Hereinafter, an embodiment of the present invention will be described with reference to the drawings. As shown in FIG. 1 and FIG. 2, the catheter 1 has a reinforcing member 2, an inner layer tube 6, and an outer layer tube 7. Hereinafter, the direction extending along the catheter 1 will be referred to as the "extension direction". An end portion corresponding to one of the two ends of the catheter 1 in the extension direction will be referred to as the "tip portion 1D". An end portion corresponding to the other of the two ends of the catheter 1 in the extension direction will be referred to as the "base portion 1P". The catheter 1 has an internal lumen 6L for passing a wire or the like. The internal lumen 6L extends in the extension direction between the tip portion 1D and the base portion 1P of the catheter 1. A connector 9 for passing a wire or the like through the catheter 1 is connected to the base portion 1P of the catheter 1. The reinforcing tube 90 reinforces the vicinity of the connection portion between the base portion 1P of the catheter 1 and the connector 9. In a plane perpendicular to the extension direction, a radial direction based on a line segment (referred to as the "center line C") passing through the center of the cross section of the catheter 1 will be referred to as the third direction. In the third direction, the side close to the center line C of the catheter 1 is referred to as the "inner side," and the side away from the center line C of the catheter 1 is referred to as the "outer side."

[0043] <Reinforcing member 2> The reinforcing member 2 is a flexible tubular member. The reinforcing member 2 reinforces the strength of the catheter 1 in the extension direction. The reinforcing member 2 extends from the distal end 1D to the proximal end 1P of the catheter 1 along the extension direction. The reinforcing member 2 is formed by forming a braided body 20 (see FIG. 3) in which multiple metallic wires are woven into a cylindrical shape and cutting both ends of the braided body 20. The center line C passes through the center of the braided body 20 and extends in the extension direction.

[0044] 3 and 4 show a state where a part of the braided body 20 is developed. The braided body 20 has a plurality of first wires 30 and a plurality of second wires 40. The plurality of first wires 30 extend along a first direction intersecting with the stretching direction. The plurality of second wires 40 extend along a second direction intersecting with the stretching direction and the first direction. The braided body 20 is a wire mesh in which the plurality of first wires 30 and the plurality of second wires 40 are woven in a net shape, so-called twill wire mesh, so that two of the first wires 30 and two of the second wires 40 cross each other. As shown in FIG. 4, the direction perpendicular to the first direction and the second direction corresponds to the third direction. The third direction is perpendicular to the stretching direction. The front side of FIG. 3 corresponds to the outside of the third direction. The back side of FIG. 3 corresponds to the inside of the third direction.

[0045] As shown in Fig. 3, each of the multiple first wires 30 is referred to as...first wire 3[n-1], first wire 3[n], first wire 3[n+1]..., and these are collectively referred to as the first wire 3. Each of the multiple second wires 40 is referred to as...second wire 4[n-1], second wire 4[n], second wire 4[n+1]..., and these are collectively referred to as the second wire 4. The multiple positions where the multiple first wires 30 and the multiple second wires 40 intersect are referred to as multiple intersections Q. In Fig. 3, of the multiple intersections Q, only the intersection Q where the first wire 3[n+2] and the second wire 4[n+4] intersect is given a reference symbol, and the reference symbols of the other multiple intersections Q are omitted.

[0046] Among the multiple intersection points Q shown in Figure 3, at intersection points Q that are located at positions that overlap with virtual straight lines L1, L2, L3, L4, and L5 extending in the extension direction, the first wire 3 is located outside the second wire 4 in the third direction (the front side of Figure 3).

[0047] The material of the first wire 3 is tungsten (W) and has a melting point of 3422°C. The cross-sectional shape of the first wire 3 is a perfect circle (see FIG. 4). The light absorption coefficient of the first wire 3 is 0.4 or more. The material of the second wire 4 is stainless steel (SUS304) and has a melting point of 1450°C. The cross-sectional shape of the second wire 4 is rectangular (see FIG. 4). The light absorption coefficient of the second wire 4 is about 0.3. The difference in melting point between the first wire 3 and the second wire 4 is about 2000°C. The melting point of the first wire 3 is at least 500°C higher than the melting point of the second wire 4. The light absorption coefficient of the first wire 3 is larger than that of the second wire 4. A black wire with a black color is used as the first wire 3 so that the light absorption coefficient of the first wire 3 is larger than that of the second wire 4.

[0048] 1 (hereinafter referred to as "tip portion 2D of reinforcing member 2") and base end portion (hereinafter referred to as "base portion 2P of reinforcing member 2 (see FIG. 1)") are each formed by cutting the braided body 20 by irradiating it with laser light. In addition, at the tip portion 2D and the base portion 2P, a plurality of joints 50 (see FIG. 5) are formed at some of a plurality of intersections Q between the plurality of first wires 30 and the plurality of second wires 40 so that the plurality of first wires 30 and the plurality of second wires 40 of the cut braided body 20 do not come undone.

[0049] 3 and 4, of the two sides in the first direction, the side close to the tip 2D (see FIG. 1) is referred to as the "first tip side," and the side close to the base 2P (see FIG. 1) is referred to as the "first base end." Of the two sides in the second direction, the side close to the tip 2D (see FIG. 1) is referred to as the "second tip side," and the side close to the base 2P (see FIG. 1) is referred to as the "second base end."

[0050] FIG. 5 is an enlarged view of a part of the tip portion 2D of the reinforcing member 2. Each of the multiple joints 50 is referred to as a joint 5[n], a joint 5[n+1], and so on, and these are collectively referred to as a joint 5. Among the multiple intersections Q, the intersections at which the joints 5 are formed are referred to as a joint intersection Qc[n], a joint intersection Qc[n+1], and so on. The joint 5[x] (x is any of n, n+1, n+2, n+3, n+4, and n+5) is formed at the joint intersection Qc[x] between the first wire 3[x] and the second wire 4[x]. The joint 5[x] joins the first wire 3[x] and the second wire 4[x] by alloying the first wire 3[x] and the second wire 4[x] at the contact portion at the joint intersection Qc[x]. In detail, the alloy at the joint 5[x] satisfies the following conditions: (1) The first wire 3[x] and the second wire 4[x] are melted by irradiation with laser light. (2) The components of the first wire 3[x] and the second wire 4[x] are mixed and diffused, and then melted and solidified. (3) The entire interface between the first wire 3[x] and the second wire 4[x] is not covered with a layer of an intermetallic compound. (4) The first wire 3[x] and the second wire 4[x] are not separated by the layer of metal compound in (3), and a solid solution is formed, with the two wires being well mixed together. The junction intersections Qc[n] and Qc[n+1], the junction intersections Qc[n+2] and Qc[n+3], and the junction intersections Qc[n+4] and Qc[n+5] are each arranged next to each other in the extension direction.

[0051] At the joint intersection Qc[x], the first wire 3[x] is disposed on the outside in the third direction (the near side in FIG. 5) with respect to the second wire [x]. As shown in FIG. 6 and FIG. 7, the part of the second wire 4[x] on the second tip side in the second direction from the joint intersection Qc[x] is curved on the outside in the third direction (the near side in FIG. 6 and FIG. 7) and is wound around the first wire 3[x]. The end of the first tip side in the first direction of the first wire 3[x] is separated from the joint intersection Qc[x]. That is, the first wire 3[x] extends slightly from the joint intersection Qc[x] to the first tip side in the first direction. The distance in the first direction between the end of the first tip side of the first wire 3[x] and the joint intersection Qc[x] is any value in the range of 0.03 mm to 0.15 mm.

[0052] FIG. 8 is a cross-sectional view showing a state where the first wire 3[x] and the second wire 4[x] are joined by the joint 5[x] at the joint intersection Qc[x]. As shown in FIG. 8, it was confirmed that the first wire 3[x] and the second wire 4[x] are mixed and recrystallized due to the solid solution formed at their respective interfaces. For example, when the first wire (metal material 1, such as steel) and the second wire (metal material 2, such as aluminum alloy) are joined by a conventional general method, as shown in FIG. 9, the first wire and the second wire are separated by an intermetallic compound layer formed at the respective interfaces between the first wire and the second wire. From this result, it was confirmed that the joint 5[x] can join the first wire 3[x] and the second wire 4[x] more firmly than in the conventional method.

[0053] <Inner tube 6, outer tube 7, soft tip 8> As shown in FIG. 2, the inner layer tube 6 has a cylindrical shape centered on the center line C, and is disposed in the inner lumen 2L of the reinforcing member 2. The material of the inner layer tube 6 is polytetrafluoroethylene (PTFE). The light transmittance of the inner layer tube 6 is 90% or more. The inner lumen 6L of the inner layer tube 6 extends in the stretching direction and forms the inner lumen 6L of the catheter 1. The inner layer tube 6 is provided to separate the inner lumen 6L of the catheter 1 from the reinforcing member 2, and prevents a wire or the like passing through the inner lumen 6L from getting caught in the reinforcing member 2.

[0054] The outer tube 7 has a cylindrical shape centered on the center line C and covers the reinforcing member 2 from the outside. The material of the outer tube 7 is a colored resin material containing a pigment. The light transmittance of the outer tube 7 is less than 90%, and more preferably, the light transmittance of the outer tube 7 is 10% to 20%. The light transmittance of the outer tube 7 is higher than that of the inner tube 6.

[0055] 1, the outer layer tube 7 has a first outer layer tube 71, a second outer layer tube 72, a third outer layer tube 73, and a fourth outer layer tube 74, each of which has a different rigidity. The first outer layer tube 71, the second outer layer tube 72, the third outer layer tube 73, and the fourth outer layer tube 74 are arranged in the extension direction, and lined up in this order from the distal end 1D to the proximal end 1P of the catheter 1. The rigidity of the outer layer tube 7 increases in the order of the first outer layer tube 71, the second outer layer tube 72, the third outer layer tube 73, and the fourth outer layer tube 74.

[0056] The soft tip 8 is provided at the tip portion 1D of the catheter 1. The soft tip 8 contacts the vicinity of the tip end of the side surface of the inner layer tube 6 and the vicinity of the tip portion 2D of the reinforcing member 2. The soft tip 8 is fixed to the inner layer tube 6 and the reinforcing member 2 by welding, and terminates the tip portion 1D of the catheter 1.

[0057] A curved portion 2R is provided near the tip portion 1D of the catheter 1. The curved portion 2R is formed by curving each of the reinforcing member 2, the inner layer tube 6, and the outer layer tube 7 with respect to the stretching direction.

[0058] <Manufacturing method of catheter 1> A method for manufacturing the catheter 1 will be described with reference to Fig. 10. In this embodiment, both ends of the reinforcing member 2 in the extension direction are joined and melted by irradiation with laser light to form the distal end 2D and the proximal end 2P, thereby manufacturing the catheter 1. It is assumed that first, the distal end of the reinforcing member 2 is cut by irradiation with laser light to form the distal end 2D, and then the proximal end of the reinforcing member 2 is cut by irradiation with laser light to form the proximal end 2P.

[0059] First, a pre-processing step is performed (S11). In the pre-processing step, the metal wire 100, the inner tube 6, and the reinforcing member 2 (see FIG. 11) are prepared. The details are as follows.

[0060] The long wire 10 wound around the bobbin is drawn out. As shown in FIG. 11, the drawn long wire 10 is roughly cut to a required length with scissors or the like. The long wire 10 has a configuration in which the inner tube 6 arranged around the cylindrical metal wire 100 is arranged in the inner cavity 2L of the reinforcing member 2. In FIG. 11, the inner tube 6 and the metal wire 100 arranged in the inner cavity 2L of the reinforcing member 2 are visualized for ease of understanding. The metal wire 100 is made of soft copper. The thermal conductivity of the metal wire 100 is 350 to 450 w / mK. The metal wire 100 can suppress a local temperature rise caused by irradiation of a laser beam during the manufacturing process by thermal diffusion. The surface of the metal wire 100 is plated in silver to reflect the laser beam irradiated during the manufacturing process. The inner tube 6 is resin-molded as a coating on the surface of the metal wire 100. The inner tube 6 has a light transmittance of 90% or more, allowing the laser light irradiated during the manufacturing process to pass through. The reinforcing member 2 is disposed outside the inner tube 6 and is exposed to the outside. Furthermore, in a previous process, the long wire 10 is degreased with an organic solvent to remove machine oil and the like that adheres to the first strands 30 and the second strands 40 (see FIG. 3) during the manufacturing of the reinforcing member 2.

[0061] 10, after the pre-processing in S11, a laser beam irradiation region is determined in order to join the first wire 3 and the second wire 4 at a joint 5 at the tip of the long wire 10 and cut the second wire 4 near the joint 5. Next, the position of the laser beam source is determined (S13) so that the laser beam is irradiated to the determined irradiation region. It is assumed that the tip portion 2D is formed by sequentially forming joints 5[x] corresponding to the respective values ​​of x when the value is changed in the order of n, n+1, n+2, n+3, and so on at the tip of the reinforcing member 2.

[0062] A case where x=n, that is, the first wire 3[n] and the second wire [n] are joined by a joint 5[n] at the joint intersection Qc[n] shown in Fig. 5, and the second wire 4[n] is cut, will be described. As shown in Fig. 12, at the joint intersection Qc[n], the first wire 3[n] is disposed on the outside in the third direction with respect to the second wire 4[n]. At the intersection Q1[n] where the first wire 3[n+1] adjacent to the second base end side in the second direction with respect to the first wire 3[n] and the second wire 4[n] intersect, the first wire 3[n+1] is disposed on the outside in the third direction with respect to the second wire 4[n]. At an intersection Q2[n] where a second wire 4[n+1] adjacent to the second wire 4[n] on the first base end side in the first direction intersects with a first wire 3[n], the second wire 4[n+1] is positioned outside the first wire 3[n] in the third direction.

[0063] The irradiation area of ​​the laser light positioned by S13 is called the first irradiation area 51[n]. The first irradiation area 51[n] is specifically defined as the following area. As shown in FIG. 13, at the joint intersection Qc[n], a joint area 53[n] where the first wire 3[n] and the second wire 4[n] overlap when the braided body 20 is viewed from the outside in the third direction is defined. In this case, the first irradiation area 51[n] includes at least a part 511 of the joint area 53[n] on the second tip side in the second direction, and a part 512 of the second wire 4[n] on the second tip side of the joint area 53[n] that does not overlap with the first wire 3[n].

[0064] The positioning of the laser light source is performed using an imaging system. The imaging system can display the center and periphery of the optical path of the laser light, which is determined according to the position of the light source. The diameter of the circle drawn by the periphery of the optical path of the laser light (the spot diameter of the laser light) is set to be equal to or smaller than the diameter of the first wire 3 or the width of the second wire 4.

[0065] As shown in Fig. 10, after the positioning of the light source of the laser light in S13, spraying of the inert gas in a laminar flow state toward the vicinity of the first irradiation region 51[n] (see Fig. 13) of the braided body 20 is started (S15). Specifically, the inert gas is argon gas or helium gas. Next, the laser light is output from the light source while the inert gas is being sprayed. As a result, the laser light is irradiated onto the first irradiation region 51[n] from the outside in the third direction (S17).

[0066] When the first irradiation region 51[n] is irradiated with the laser light in S17, the first wire 3[n] is irradiated with the laser light first, as shown in FIG. 14A. As a result, the energy of the laser light is provided to the first wire 3[n], which heats and melts. The energy of the laser light is reduced by being provided to the first wire 3[n]. The second wire 4[n] is then irradiated with the laser light. As a result, the energy of the laser light is provided to the second wire 4[n], which heats and melts and cuts. As a result, as shown in FIG. 14B, the first wire 3[n] and the second wire 4[n] come into contact with each other at their melted portions, and are alloyed and joined together. Also, the second wire 4[n] is melted at a portion closer to the second tip side in the second direction than the joint 5[n], and curves outward in the third direction and winds around the first wire 3[n] (see Figs. 6 and 7). After the first wire [n] and the second wire [n] are joined at the joint intersection Qc[n], the irradiation of the laser light from the light source is stopped.

[0067] In S17, the joining of the first wire 3[n] and the second wire 4[n] and the melting of the second wire [4] are achieved by irradiating one pulse of laser light. Therefore, compared to when each of these is performed in a separate process, there is less chance of misalignment between the position of the joint intersection Qc[n] and the melting position of the second wire 4[n].

[0068] In addition, during the process of joining the first wire 3[n] and the second wire 4[n] by irradiation with laser light and melting the second wire 4[n], the first wire 3 and the second wire 4 may heat up at a position other than the joint intersection Qc[n] due to irradiation with laser light. In this case, the physical properties of the first wire 3 and the second wire 4 may change due to heat in an area other than the joint intersection Qc[n], or melting may occur, which is not preferable. In contrast, in this embodiment, the energy provided to the braid 20 by irradiation with laser light is changed over time and irradiated. This reduces the possibility that the first wire 3 and the second wire 4 may heat up at a position other than the joint intersection Qc[n] due to irradiation with laser light. Details are as follows.

[0069] As shown in FIG. 15A, in S17, one pulse of laser light is divided and intermittently irradiated multiple times. More specifically, the laser light is irradiated while repeatedly switching between a period of relatively high intensity (hereinafter referred to as a "high level period") and a period of relatively low intensity (hereinafter referred to as a "low level period"). In this case, heat generated by the energy of the laser light in the first wire 3 or the second wire 4 of the braided body 20 is unlikely to diffuse to the surroundings. This is because the heat cools during the low level period when the intensity of the irradiated laser light is relatively low, and the diffusion to the surroundings is suppressed. This effect is generally called the pulse division effect (Cool effect). In this case, as shown in FIG. 15B, one pulse of laser light is continuously irradiated at a constant intensity, so that the diffusion of heat to the surroundings (arrow Y1) can be suppressed.

[0070] The intensity and irradiation time of the laser light are adjusted so that one pulse of energy can provide the energy required to melt the first wire 3. The intensity of the laser light during the low-level period may be less than half the intensity of the laser light during the high-level period. In other words, the intensity of the laser light during the low-level period may be any value between 0% and 50% of the intensity of the laser light during the high-level period. If the intensity of the laser light during the low-level period is set to 0, irradiation of the laser light is stopped during the low-level period. The duration of the low-level period is any value between 10% and 100% of the duration of the high-level period.

[0071] As shown in Fig. 10, after the irradiation of the laser light to the first irradiation region 51[n] is completed in S17, the spraying of the inert gas started in S15 is stopped (S19). Next, an irradiation region of the laser light to be irradiated to cut the first wire 3[n] in the vicinity of the joint 5[n] is determined. The first wire 3[n] is cut at a position of the first wire 3[n] shown in Fig. 5 that is separated from the joint intersection Qc[n] toward the first tip side in the first direction.

[0072] Next, the light source of the laser light is positioned so that the determined irradiation region is irradiated with the laser light (S21). As shown in FIG. 12, the irradiation region of the laser light positioned by S21 is referred to as the second irradiation region 52[n]. As shown in FIG. 10, after the positioning of the light source of the laser light by S21, spraying of the inert gas in a laminar flow state toward the vicinity of the second irradiation region 52[n] of the braided body 20 is started (S23). Next, the laser light is output from the light source while the inert gas is being sprayed. As a result, the laser light is irradiated onto the second irradiation region 52[n] from the outside in the third direction (S25).

[0073] As shown in Fig. 16A, when the laser light is irradiated in S25, the laser light provides energy to the second irradiation region 52[n] of the first wire 3[n]. As a result, as shown in Fig. 16B, the first wire 3[n] melts at a position closer to the first tip in the first direction than the joint 5[n]. After the first wire [n] is melted, the irradiation of the laser light from the light source is stopped.

[0074] The irradiation conditions of the laser light irradiated to the second irradiation region 52[n] in S23 are the same as those of the laser light irradiated to the first irradiation region 51[n] in S17. That is, one pulse of laser light is divided and irradiated intermittently multiple times. Therefore, the heat generated by the energy of the laser light in the first wire 3[n] is unlikely to diffuse to the surroundings. Therefore, as shown in FIG. 17A, the fusion part 301 of the first wire 3[n] that is fused by the irradiation of the laser light does not move after the irradiation of the laser light stops, and is maintained at the position immediately after the irradiation of the laser light. Therefore, for example, as shown in FIG. 17B, by continuously irradiating one pulse of laser light with a constant intensity, the heat is diffused to the surroundings, and the fusion part 301 of the first wire 3[n] can be prevented from moving toward the joint part 5[n] (arrow Y2).

[0075] As described above, the fusion portion 301 of the first wire 3[n] and the second wire 4[n] are kept apart, and the heat of the fusion portion 301 of the first wire 3[n] is not transferred to the second wire 4[n]. Therefore, even if the second irradiation region 52[n] is irradiated with laser light, the composition of the second wire 4[n] does not change except at the joint 5[n]. In other words, the composition of the second wire 4[n] is the same except at the joint 5[n], regardless of the distance from the joint 5[n].

[0076] As shown in FIG. 10, after the irradiation of the laser light onto the second irradiation region 52[n] is completed in S25, the spraying of the inert gas started in S23 is stopped (S27).

[0077] Next, it is determined whether or not the joining and melting of the first wire 3 and the second wire 4 at the tip of the reinforcing member 2 are all completed (S29). If the joining and melting are not all completed (S29: NO), the process returns to S13. x is updated from n to n+1, and the processes of S13 to S27 are repeated. As a result, as shown in FIG. 5, the first wire 3[n+1] and the second wire 4[n+1] are joined by the joint 5[n+1] at the joint intersection Qc[n+1], and the second wire 4[n+1] is cut (S13 to S19). In addition, the first wire 3[n+1] is melted at a position of the first wire 3[n+1] that is spaced from the joint intersection Qc[n+1] toward the first tip side in the first direction (S21 to S27). At this time, the joints 5[n] and 5[n+1] are arranged in the stretching direction.

[0078] The above process is repeated while x is updated in the order of n+2, n+3. As a result, as shown in FIG. 5, the first wire 3[n+2] and the second wire 4[n+2] are joined by the joint 5[n+1] at the joint intersection Qc[n+2], and the second wire 4[n+2] is cut (S13 to S19). In addition, the first wire 3[n+2] is melted at a position of the first wire 3[n+2] that is separated from the joint intersection Qc[n+2] toward the first tip side in the first direction (S21 to S27). In addition, the first wire 3[n+3] and the second wire 4[n+3] are joined by the joint 5[n+3] at the joint intersection Qc[n+3], and the second wire 4[n+3] is cut (S13 to S19). Also, the first wire 3[n+3] is melted at a position spaced from the joint intersection Qc[n+3] toward the first tip side in the first direction (S21 to S27). At this time, the joints 5[n+2] and 5[n+3] are aligned in the extension direction.

[0079] The same process as above is repeatedly executed while x is updated in the order of n+4, n+5. As a result, the joints 5[n+4] and 5[n+5] shown in FIG. 5 are formed. The joints 5[n+4] and 5[n+5] are arranged in the extension direction. The joints 5[n], 5[n+2], 5[n+4] and the joints 5[n+1], 5[n+3], 5[n+5] are arranged in a direction perpendicular to the extension direction. As a result, the reinforcing member 2 is cut at the tip in a direction perpendicular to the extension direction, and the tip portion 2D is formed.

[0080] As shown in FIG. 10, when it is determined that the joining and melting of the first wire 3 and the second wire 4 at the tip of the reinforcing member 2 are all completed (S29: YES), proceed to S31. It is determined whether the joining and melting of the first wire 3 and the second wire 4 are all completed at both the tip and base ends of the reinforcing member 2 (S31). When the joining and melting of only the tip of the reinforcing member 2 is completed and the joining and melting of the base end is not completed (S31: NO), return to S13. Next, the same process as for the tip portion is performed on the first wire 3 and the second wire 4 at the base end of the reinforcing member 2 (S13 to S29). As a result, the base end of the reinforcing member 2 is cut to form the base end 2P (see FIG. 1). Since both ends of the reinforcing member 2 are cut to form the tip end 2D and the base end 2P (S31: YES), proceed to S33.

[0081] Next, a post-step of disposing the outer layer tube 7 around the reinforcing member 2 is performed (S33). As shown in Fig. 18, the metal wire 100, the inner layer tube 6, and the reinforcing member 2 are inserted in order into the lumen 74L of the fourth outer layer tube 74, the lumen 73L of the third outer layer tube 73, and the lumen 72L of the second outer layer tube 72. Although not shown in Fig. 18, the metal wire 100, the inner layer tube 6, and the reinforcing member 2 are also inserted into the lumen of the first outer layer tube 71. The outer layer tubes 7 are arranged in the order of the first outer layer tube 71 (see Fig. 1), the second outer layer tube 72, the third outer layer tube 73, and the fourth outer layer tube 74 from the distal end 2D to the proximal end 2P (see Fig. 1) of the reinforcing member 2.

[0082] 10, after the post-processing step (S33) is completed, the tip portion 2D of the reinforcing member 2 is terminated by a soft tip 8 (S35). Finally, the metal wire 100 is removed from the lumen 6L of the inner layer tube 6 (S37). With the above, the manufacturing process of the catheter 1 is completed.

[0083] <How to use Catheter 1> An example of a method of using the catheter 1 will be described. First, the user shapes the tip of the catheter 1 as necessary. The user is a doctor or the like. Next, the inner lumen 6L of the catheter 1 is passed through the guide wire that has been inserted into the blood vessel in advance. The user applies force to the base end side of the catheter 1, and pushes the catheter 1 into the blood vessel in sequence from the tip side. The user rotates the catheter 1 as necessary to orient the tip of the catheter 1 in a desired direction. In this way, the user causes the tip of the catheter 1 to reach the target site in the blood vessel. After that, the user removes the guide wire from the catheter 1. In this state, the user injects a contrast agent from the connector 9 or inserts an embolic substance as necessary.

[0084] <Actions and Effects of the Present Embodiment> In the catheter 1, the first wire 3[x] and the second wire 4[x] are alloyed at their contact portions and the first wire 3[x] and the second wire 4[x] are joined to form a joint 5[x]. Therefore, in the case where the braid 20 made of a plurality of first wires 30 and a plurality of second wires 40 whose melting points differ by 500°C or more is used as the reinforcing member 2, the catheter 1 can make the end portion in the extension direction of the reinforcing member 2 less likely to unravel.

[0085] The reinforcing member 2 is curved at the curved portion 2R. The joint 5[x] of the reinforcing member 2 can maintain the state in which the first wire [x] and the second wire [x] are joined to each other, even if a force is applied as a result of the reinforcing member 2 being curved at the curved portion 2R.

[0086] The second wire 4[x] has a portion on the second tip side of the joint intersection Qc[x] that curves outward in the third direction and is wound around the first wire 3[x] (see Figs. 6 and 7). In this case, the catheter 1 can further firmly join the first wire 3[x] and the second wire 4[x].

[0087] The catheter 1 includes an inner-layer tube 6. When a wire or the like passes through the inner lumen 2L of the reinforcing member 2, the inner-layer tube 6 can prevent the wire or the like from getting caught on the reinforcing member 2. The catheter 1 also includes an outer-layer tube 7 that covers the reinforcing member 2 from the outside. The outer-layer tube 7 can prevent the reinforcing member 2 from being exposed. Therefore, the catheter 1 can reduce the possibility that the reinforcing member 2 will get caught on a blood vessel when passing through the blood vessel.

[0088] The inner tube 6 has a higher light transmittance than the outer tube 7. In this case, when the first wire 3[x] and the second wire 4[x] are joined by irradiating them with a laser beam, the inner tube 6 is prevented from generating heat due to absorption of the laser beam. Therefore, the catheter 1 is less likely to generate heat when irradiated with a laser beam, and the first wires 30 and the second wires 40 are deformed by the heat at locations other than the joint 5[x]. Furthermore, by using polytetrafluoroethylene as the material for the inner tube, an inner tube 6 with high light transmittance can be easily realized.

[0089] The first wire 3[x] is disposed on the outside in the third direction relative to the second wire 4[x]. In this case, during the manufacturing process of the catheter 1, the first wire 3[x] can be appropriately irradiated with laser light from a light source disposed on the outside in the third direction, and the first wire 3[x] and the second wire 4[x] can be appropriately joined. Furthermore, during irradiation with laser light, more energy of the laser light can be imparted to the first wire 3[x], which has a higher melting point, to melt the first wire 3[x]. Furthermore, the imparting of energy of the laser light to the second wire 4[x], which has a lower melting point, can be suppressed, and the second wire 4[x] can be melted and cut.

[0090] The cross-sectional shape of the first wire 3 is a perfect circle, and the cross-sectional shape of the second wire 4 is a rectangle. In this case, a gap can be formed between the first wire 3[x] and the second wire 4[x] before they are joined. Therefore, it is easy to melt the portions of the first wire 3[x] and the second wire 4[x] that form the gap, bring them into contact, and alloy them. Therefore, it is easy to alloy the first wire 3[x] and the second wire 4[x] at the contact portions, and form the joint 5[x].

[0091] The multiple first wires 30 have a larger absorption coefficient than the multiple second wires 40. In this case, the process of simultaneously melting and alloying the first wires 3[x] having a relatively high melting point and the second wires 4[x] having a relatively low melting point, and melting and cutting the second wires [x] can be achieved by irradiating the laser light once.

[0092] The composition of the second wire 4[x] does not change even when a laser beam is applied to melt the first wire [x], except for the joint 5[x]. Therefore, the composition of the second wire 4[x], except for the joint 5[x], is the same regardless of the distance from the joint 5[x]. Therefore, the catheter 1 can stably maintain the composition of the second wire 4, and therefore the strength of the braid 20 can be maintained.

[0093] The first wires 30 are made of tungsten, and the second wires 40 are made of stainless steel (SUS). In this case, the catheter 1 can be easily pushed in due to the high hardness of tungsten. In addition, since tungsten has excellent radiation shielding properties, the position of the catheter 1 inside the body can be easily confirmed by irradiating it with radiation.

[0094] When any part of the long wire 10 is cut to manufacture the catheter 1, there is a possibility that the ends may come undone due to the elasticity of the first wire 3 and the second wire 4. Furthermore, when tungsten is used as the first wire 3, although the pushability of the catheter 1 is improved due to its high hardness, it cannot be easily cut with an ordinary blade.

[0095] In contrast, in the manufacturing method of the catheter 1 shown in FIG. 10, the laser light irradiated to the first irradiation region 51[x] in S13 first provides energy to a part of the first wire 3[x] to melt the first wire 3[x]. At the same time, the laser light provides energy to the second wire 4[x] to melt and cut the second wire [x], and the melted first wire 3[x] and second wire 4 "x" are alloyed and joined. The laser light irradiated to the second irradiation region 52[x] in S25 provides energy to the first wire 3[x] to melt the first wire 3[x]. The above steps are repeated until both ends of the reinforcing member 2 are cut to form the tip portion 2D and the base portion 2P. As a result, the tip portion 2D and the base portion 2P of the reinforcing member 2 are less likely to melt due to the joint portion 5[x].

[0096] When the joining of the first wire 3[x] and the second wire 4[x] and the cutting of the second wire 4[x] are realized by irradiating different laser beams, the position of the second wire 4[x] is shifted by the first laser beam irradiation, and accordingly the position of the melting part of the second wire 4[n] is shifted from the intended position. In this case, the position of the joint 5 "n" and the melting part of the second wire 4[n] may be shifted. In contrast, in this embodiment, by irradiating the laser beam once in S13, the joining of the first wire 3[x] and the second wire 4[x] by alloying and the melting of the second wire 4[x] are performed simultaneously. Therefore, the possibility of the joint 5[x] and the melting position of the second wire 4[x] being shifted can be reduced, and the accuracy of the positional relationship between the joint 5[x] and the melting position of the second wire 4[x] can be maintained with good accuracy.

[0097] The energy of the laser light irradiated in S13 is first applied to the first wire 3[x], and the remaining energy is applied to the second wire 4[x]. Therefore, even if the melting point of the first wire 3 is 500°C or more higher than the melting point of the second wire 4, the joining of the first wire 3[x] and the second wire 4[x] and the melting of the second wire 4[x] can be efficiently performed by irradiating the laser light once.

[0098] For example, when the first wire 3[x] and the second wire 4[x] are joined after the first wire 3[x] is melted, the first wire 3[x] may move during melting, and the positional relationship between the first wire 3[x] and the second wire 4[x] may be shifted. In this case, the joining of the first wire 3[x] and the second wire 4[x] may not be performed with high accuracy. In contrast, in this embodiment, the first wire 3[x] is melted after the joining of the first wire 3[x] and the second wire 4[x]. In this case, the position of the first wire 3[x] relative to the second wire 4[x] is less likely to shift due to the joining of the first wire 3[x] and the second wire 4[x]. Therefore, the joining of the first wire 3[x] and the second wire 4[x] and the cutting of the first wire 3[x] can be performed with high accuracy.

[0099] In this embodiment, the energy provided to the braided body 20 by the irradiation of the laser light in S13 and S25 is changed over time. More specifically, during the irradiation of the laser light in S13 and S25, the laser light is intermittently irradiated multiple times. In this case, it is possible to suppress the transfer of heat from the irradiation area of ​​the laser light in the first wire 3 and the second wire to the surroundings. In this case, it is possible to prevent the first wire 3 and the second wire 4 arranged near the irradiation area of ​​the laser light from melting, evaporating, or disappearing. In addition, the irradiation conditions of the laser light in S13 and the irradiation conditions of the laser light in S25 are the same. In other words, the irradiation conditions of the laser light in different processes can be made common, so that the manufacturing work of the catheter 1 can be made more efficient.

[0100] At the joint intersection Qc[x], the first wire 3[x] is disposed outside the second wire 4[x] in the third direction. At the intersection Q1[x] where the first wire 3[x+1] adjacent to the first wire 3[x] intersects with the second wire 4[x], the first wire 3[x+1] is disposed outside the second wire 4[x] in the third direction. In this case, when the first wire 3[x] and the second wire 4[x] are joined at the joint intersection Qc[x] by irradiating laser light in S13, the second wire 4[x] can be prevented from moving outside in the third direction by the first wire 3[x+1] pressing it from the outside in the third direction. In addition, at the intersection Q2[x] where the second wire 4[x+1] adjacent to the second wire 4[x] intersects with the first wire 3[x], the second wire 4[x+1] is disposed outside the first wire 3[x] in the third direction. In this case, when the first wire 3[x] and the second wire 4[x] are joined at the joining intersection Qc[x] by irradiating a laser beam in S13, the second wire 4[x+1] presses the first wire 3[x] from the outside in the third direction to prevent it from moving outside in the third direction. Therefore, the positions of the first wire 3[x] and the second wire[x] can be stabilized when they are joined, so that the first wire 3[x] and the second wire 4[x] can be stably joined at the joint 5[x].

[0101] The joints 5[n] and 5[n+1] are arranged side by side in the extension direction. The joints 5[n+2] and 5[n+3] are arranged side by side in the extension direction. The joints 5[n+4] and 5[n+5] are arranged side by side in the extension direction. In addition, the joints 5[n], 5[n+2], and 5[n+4] are arranged in a direction perpendicular to the extension direction. The joints 5[n+1], 5[n+3], and 5[n+5] are arranged in a direction perpendicular to the extension direction. By arranging the joints 5 in this manner, the reinforcing member 2 can be cut in a direction perpendicular to the extension direction to form the tip portion 2D and the base portion 2P.

[0102] In S17 and S25, the laser light is irradiated while a laminar inert gas is being sprayed onto the reinforcing member 2. In this case, since it is possible to prevent the surrounding air from coming into contact with the first wires 3 and the second wires 4 when the first wires 3 and the second wires 4 are heated by the irradiation of the laser light, it is possible to suppress the occurrence of oil burning or oxidation of the first wires 3 and the second wires 4 due to the laser irradiation.

[0103] In the long wire 10 prepared in the previous step S11, the inner layer tube 6 is disposed around the metal wire 100, and the metal wire 100 and the inner layer tube 6 are disposed in the inner cavity 2L of the reinforcing member 2. After the reinforcing member 2 is cut at both ends in the extension direction, the outer layer tube 7 is disposed around the reinforcing member 2 in the subsequent step S33. This allows the catheter 1 to be manufactured, which includes the reinforcing member 2, the inner layer tube 6, and the outer layer tube 7. In particular, the catheter 1 with the thin inner layer tube 6 can be easily manufactured by using the metal wire 100. The surface of the metal wire 100 is plated in silver to reflect the laser light irradiated during the manufacturing process. In this case, the irradiated laser light can be prevented from passing through the inner cavity 6L of the inner layer tube 6 to reach the opposite side. This reduces the possibility that the reinforcing member 2 on the opposite side will be melted by the laser light.

[0104] The inner tube 6 has a higher light transmittance than the outer tube 7, which prevents the inner tube 6 from absorbing the laser light and generating heat, thereby reducing the possibility that the inner tube 6 will melt or break due to heat generated by irradiation with the laser light.

[0105] The thermal conductivity of the metal wire 100 is set to 350 to 450 w / mK. In this embodiment, a material with high thermal conductivity is used as the material of the metal wire 100 to promote thermal diffusion. By using a material with high thermal conductivity in the metal wire 100 in this manner, a local temperature rise in the metal wire 100 can be suppressed by thermal diffusion. Therefore, the possibility that the inner layer tube 6 will melt due to a temperature rise in the metal wire 100 can be reduced.

[0106] <Modification> The present invention is not limited to the above embodiment, and various modifications are possible. The joint 5[x] that joins the first wire 3[x] and the second wire 4[x] may be formed only on the tip side of the reinforcing member 2, and not on the base end side. Alternatively, the joint 5[x] that joins the first wire 3[x] and the second wire 4[x] may be formed only on the base end side of the reinforcing member 2, and not on the tip side. The difference in melting point between the multiple first wires 30 and the multiple second wires 40 was about 2000°C. In contrast, the melting point of the multiple first wires 30 may be about 500°C higher than the melting point of the multiple second wires 40. In this case, copper may be used as the material of the multiple first wires 30, and SUS may be used as the material of the multiple second wires 40. The melting point of the multiple first wires 30 may be about 700°C higher than the melting point of the multiple second wires 40. In this case, aluminum may be used as the material of the plurality of first wires 30, and SUS may be used as the material of the plurality of second wires 40. The melting point of the plurality of first wires 30 may be about 1000° C. higher than the melting point of the plurality of second wires 40. In this case, aluminum may be used as the material of the plurality of first wires 30, and titanium may be used as the material of the plurality of second wires 40. In the above embodiment, the melting point of the plurality of first wires 30 is specified to be 500° C. or more higher than the melting point of the plurality of second wires 40, but it may be more preferably 700° C. or more higher, and even more preferably 1000° C. or more higher.

[0107] The curved portion 2R of the catheter 1 may be provided near the base end 2P, or may be provided at both the tip end 2D and the base end 2P. The curved portion 2R of the catheter 1 may be formed by the user. In this case, the catheter 1 may be shipped in a state in which it extends linearly in the extension direction. The catheter 1 may be used after the curved portion 2R is formed at the tip end 2D by the user.

[0108] The portion of the second wire 4[x] on the second tip side of the joint intersection Qc[x] may extend straight without being curved. In the above, the end of the first wire 3[x] on the first tip side, i.e., the end melted by irradiation with laser light, is separated from the joint intersection Qc[x] by 0.03 mm to 0.15 mm on the first tip side in the first direction, but this distance can be changed as appropriate.

[0109] The catheter 1 may have only the inner layer tube 6 and the reinforcing member 2, and not the outer layer tube 7. Or, the catheter 1 may have only the reinforcing member 2 and the outer layer tube 7, and not the inner layer tube 6. The hardness of the outer layer tube 7 may be uniform throughout the entire stretching direction. The inner layer tube 6 may have portions with different hardness. The portions of the inner layer tube 6 with different hardness may be arranged in the stretching direction. The thickness of the outer layer tube 7 does not need to be uniform in the stretching direction, and multiple portions with different thicknesses may be arranged in the stretching direction. The catheter 1 may be composed of only the reinforcing member 2.

[0110] The light transmittance of the inner tube 6 is not limited to that in the above embodiment and may be other values. The light transmittance of the inner tube 6 may be the same as or lower than that of the outer tube 7. The material of the inner tube 6 is not limited to PTFE and may be other materials. The light absorption coefficient of the first strands 30 may be the same as or lower than that of the second strands 40.

[0111] The cross-sectional shape of the multiple first wires 30 is not limited to a perfect circle and may be an ellipse. The cross-sectional shape of the multiple first wires 30 may be rectangular, and the cross-sectional shape of the multiple second wires 40 may be circular. The cross sections of both the multiple first wires 30 and the multiple second wires 40 may be either circular or rectangular.

[0112] The material of the first strands 30 is not limited to tungsten. The material of the second strands 40 is not limited to SUS. The material of the first strands 30 and the second strands 40 may be any of various materials as long as the melting point of the first strands 30 is at least 500° C. higher than the melting point of the second strands 40. For example, the first strands 30 may be made of molybdenum, platinum, or gold, and the second strands 40 may be made of nickel alloy, titanium alloy, or aluminum alloy. The first strands 30 and the second strands 40 may be made of SUS having different compositions.

[0113] The irradiation pattern in the case of irradiating the laser light in S13 and S25 is not limited to the above embodiment. For example, as shown in FIG. 19A, in S13 and 25, a laser light having a relatively low intensity may be irradiated first, and then, as shown in FIG. 19B, a laser light having a relatively high intensity may be irradiated. In this case, by irradiating the laser light having a relatively low intensity first, the range of the part in the first wire 3 and the second wire 4 that is heated by the laser light can be limited. This effect is generally called the slow-up effect. Therefore, in the case of irradiating the laser light having a relatively high intensity, sufficient energy can be provided to the first wire 3 and the second wire 4 even if the intensity of the laser light is suppressed. In other words, since the energy provided to the first wire 3 and the second wire 4 can be localized, it is possible to prevent the first wire 3 and the second wire 4 from melting, evaporating, or disappearing in the vicinity of the irradiation area of ​​the laser light.

[0114] The output pattern of the laser light in S13 and S25 is not limited to the above. For example, an operation of intermittently irradiating the laser light and an operation of gradually increasing the intensity of the laser light may be used in combination. The number of times when the laser light is irradiated intermittently is not limited to the above embodiment. A laser light with a relatively high intensity may be irradiated first, and then a laser light with a relatively low intensity may be irradiated. The change in the irradiation mode of the laser light may be performed only in S13, and not in S25. Conversely, the change in the irradiation mode of the laser light may be performed only in S25, and not in S13. The laser light irradiated by S13 and S25 may be continuously irradiated with a uniform intensity. In other words, the energy provided to the braided body 20 by the irradiation of the laser light may not change over time.

[0115] The braid 20 may be a wire mesh in which a plurality of first wires 30 and a plurality of second wires 40 cross each other alternately, that is, a so-called plain weave wire mesh. In addition, the manner in which the plurality of first wires 30 and the plurality of second wires 40 are woven is not limited to a plain weave wire mesh or a twill weave wire mesh, and other manners may be used. In this case, at the intersection Q1[x], the first wire 3[x+1] may be disposed inside the second wire 4[x] in the third direction. At the intersection Q2[x], the second wire 4[x+1] may be disposed inside the first wire 3[x] in the third direction.

[0116] Instead of spraying the inert gas in a laminar flow state starting in S15 and S23, an inert gas may be injected and filled as the atmosphere around the reinforcing member 2 before the laser light is irradiated. The material and conductivity of the metal wire 100 used in the manufacturing process of the catheter 1 are not limited to the above embodiment. The metal wire 100 does not have to be used in the manufacturing process of the catheter 1.

Claims

1. The wire harness is made of a braided body in which a plurality of first wires extending in a first direction and a plurality of second wires extending in a second direction intersecting the first direction are woven in a net shape, and is provided with at least a tubular reinforcing member extending in the extension direction; The melting point of the first wires is 500° C. or more higher than the melting point of the second wires, the first strands have a larger absorption coefficient than the second strands, At least one of both ends in the extension direction of the reinforcing member has a plurality of joints arranged in the extension direction and in a direction perpendicular to the extension direction at some of a plurality of intersections where the plurality of first wires and the plurality of second wires intersect, The joint is Joining first crossing wires and second crossing wires, which are the first wires and the second wires that cross each other at some of the intersections, The first cross wire and the second cross wire are joined by alloying at their contact portions, In the joint portion, the first intersecting wire is disposed on one side of the second intersecting wire in a third direction perpendicular to the first direction and the second direction, One side in the third direction is the outer side of the reinforcing member. A catheter characterized by:

2. The catheter according to claim 1 , wherein at least one of both end portions in the extension direction of each of the first wires and the second wires has a curved portion curved with respect to the extension direction.

3. 3. The catheter according to claim 1, wherein a second tip portion of the second cross wire, which is located on the tip side of the joint portion, is wound around the first cross wire.

4. an inner layer tube having a cylindrical shape centered on a central axis of the reinforcing member and disposed in an inner cavity of the reinforcing member; an outer layer tube having a cylindrical shape centered on the central axis and covering the reinforcing member from the outside; 4. The catheter according to claim 1, further comprising:

5. 5. The catheter according to claim 4, wherein the inner tube has a higher light transmittance than the outer tube.

6. 6. The catheter according to claim 4, wherein the material of the inner layer tube is polytetrafluoroethylene.

7. One of the plurality of first wires and the plurality of second wires has a circular cross-sectional shape, The other of the plurality of first wires and the plurality of second wires has a rectangular cross-sectional shape. A catheter according to any one of claims 1 to 6.

8. The first wires have a circular cross-sectional shape, The cross-sectional shape of the plurality of second wires is rectangular. The catheter according to claim 7.

9. 9. The catheter according to claim 1, wherein the composition of the second cross wires excluding the joint is the same regardless of the distance from the joint.

10. 10. The catheter according to claim 1, wherein the material of the first strands is tungsten, and the material of the second strands is stainless steel.

11. 11. The catheter according to claim 1, wherein the absorption coefficient of the first strands is 0.4 or more, which is greater than the absorption coefficient of the second strands by 0.1 or more.

Images