Guide wire

Abstract

To provide a guidewire that ensures no gap is ever created between the resin sleeve and the posterior end coil, and offers good insertability when inserting into curved blood vessels and good compatibility with concomitant devices. [Solution] The device comprises a core wire 10, a resin sleeve 20, a front coil 30, a rear coil 40, and an inner coil 50. The front coil 30 is fixed to the distal end small diameter portion 11 of the core wire 10 by solder 61 and 62 at its front 31 and rear 32, respectively. The rear coil 40 consists of a solder-penetrated rear end portion 42 into which solder 64 for fixing the rear coil 40 to the distal end small diameter portion 11 of the core wire 10 has penetrated, and a solder-non-penetrated front end portion 41 into which such solder has not penetrated.

Description

Technical Field

[0001] The present invention relates to a guide wire used when inserting a medical device into a living body.

Background Art

[0002] Conventionally, as a medical guide wire with low resistance and good straightness, a guide wire has been proposed in which a resin sleeve is arranged at a small-diameter portion on the distal end side of a core wire (see Patent Document 1 below).

[0003] The guide wire described in this document includes a core wire, a sleeve made of polyimide arranged at a small-diameter portion on the distal end side of this core wire, and a tip-side coil and a rear-end-side coil arranged at the small-diameter portion on the distal end side of the core wire so as to sandwich this sleeve. The sleeve constituting this guide wire is supposed to have good torque transmission by being arranged rotatably around the small-diameter portion on the distal end side of the core wire (paragraph 0024 of this document).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] When manufacturing a guide wire as described in Patent Document 1, in the process of fixing (soldering) a rear-end-side coil to a small-diameter portion on the distal end side of a core wire, there is a problem that the rear end portion of the sleeve melts due to the heat of the solder used.

[0006] To avoid this problem, the rear coil must be soldered at a certain distance from the rear end of the sleeve. Therefore, in the guide wires actually manufactured, the tip of the rear coil cannot be brought into contact with the rear end surface of the sleeve, and as shown in Figure 12, a gap G (a step between the sleeve and the core wire, and a step between the rear coil and the core wire) is inevitably formed between the sleeve and the rear coil.

[0007] Furthermore, the presence of such gaps increases insertion resistance when inserting a guidewire into curved blood vessels, and the stepped portion of the gap may come into contact with plaque inside the blood vessel, impairing insertion. Additionally, these gaps (steps) impair the compatibility with other devices such as catheters.

[0008] Furthermore, if the guidewire is bent, such as when inserted into a curved blood vessel, the sleeve moves slightly toward the tip relative to the core wire, and the rear end surface of the sleeve is displaced in the same direction. As a result, the gap (the distance between the rear end surface of the sleeve and the tip of the rear end coil) tends to widen compared to before bending.

[0009] The present invention was made based on the circumstances described above, and its purpose is to provide a guide wire that does not create a gap between the sleeve and the rear end coil, has good insertability into curved blood vessels and good matching with concomitant devices, and does not melt the rear end of the resin sleeve due to the heat during soldering during its manufacture (soldering process of the rear end coil). [Means for solving the problem]

[0010] (1) The guide wire of the present invention comprises a core wire, a resin sleeve rotatably disposed around the small diameter portion at the distal end of the core wire, and a compression coil spring having substantially the same outer diameter as the resin sleeve, and is disposed on the tip side of the resin sleeve so as to surround the small diameter portion at the distal end of the core wire, with its rear end in contact with the tip surface of the resin sleeve, and a compression coil spring having substantially the same outer diameter as the resin sleeve, and surrounds the small diameter portion at the distal end of the core wire The device comprises a rear-end coil positioned on the rear end side of the resin sleeve, the tip of which abuts against the rear end surface of the resin sleeve, the front-end coil being fixed to the small-diameter distal end portion of the core wire by solder at both its front and rear ends, the rear-end coil being characterized by having a solder-penetrated rear end portion into which solder for fixing the rear-end coil to the small-diameter distal end portion of the core wire has penetrated, and a solder-non-penetrated front end portion into which such solder has not penetrated.

[0011] With a guide wire of this configuration, the tip of the rear-end coil, which is made of a compression coil spring having substantially the same outer diameter as the resin sleeve, abuts against the rear end surface of the resin sleeve, so that no gap (step) is created between the resin sleeve and the rear-end coil. Furthermore, during the manufacturing of the guide wire (the soldering process of the rear end coil), the rear end coil is soldered (formation of the solder-penetrating rear end) at a position sufficiently separated from the rear end of the resin sleeve by a length equivalent to the length of the solder-free tip. Therefore, the rear end of the resin sleeve will not melt due to the heat generated during soldering.

[0012] Furthermore, even if the guidewire is bent due to insertion into a curved blood vessel, causing the resin sleeve to move relative to the core wire in the tip direction and the rear end surface of the resin sleeve to be displaced in the same direction, the solder-non-penetrating tip extends due to its compression spring characteristics, and the tip of the rear end coil follows the displacement, thus maintaining contact with the rear end surface of the resin sleeve.

[0013] Also, for example, by pushing the guide wire while the resin sleeve is sandwiched and stacked at the vascular stenosis portion, the resin sleeve moves relative to the core wire in the rear end direction. Even if the rear end surface tries to be displaced in the same direction, due to the compression spring characteristics of the solder non-penetrating tip portion, this movement can be blocked, and the compression load applied to the resin sleeve due to the pushing of the guide wire can be relaxed. Thereby, no kink or the like is generated in the resin sleeve.

[0014] (2) In the guide wire of the present invention, the coil outer diameter (D 40 ) of the rear end side coil is 0.24 to 0.46 mm, the length (L 41 ) of the solder non-penetrating tip portion is 0.4 to 1.6 mm, and the length (L 42 ) of the solder penetrating rear end portion is preferably 0.4 to 1.6 mm. Here, the length (L 41 ) of the solder non-penetrating tip portion and the length (L 42 ) of the solder penetrating rear end portion are the lengths in the state of being fixed to the distal end side small diameter portion of the core wire, respectively.

[0015] (3) In the compression coil spring constituting the rear end side coil, the free length (length in the non-compressed state) of the portion that becomes the solder non-penetrating tip portion is L o , and the contact length (length in the fully compressed state) of the portion is L S . Then, it is preferable that the length (L 41 ) of the solder non-penetrating tip portion satisfies the following formula.

[0016] Formula: (L S + 0.05 mm) ≦ L 41 ≦ (L o - 0.1 mm)

[0017] <H (4) In the guide wire of the present invention, it is preferable to have an inner coil made of a compression coil spring having a tip portion that is fixed to the small diameter portion at the distal end of the core wire together with the tip portion of the tip coil, and a rear end portion that is fixed to the small diameter portion at the distal end of the core wire by solder inside the resin sleeve.

[0018] With a guide wire of this configuration, the inner coil is positioned in the space formed by the outer circumferential surface of the small-diameter portion at the distal end of the core wire, the inner circumferential surface of the tip coil, and the inner circumferential surface of the resin sleeve. This allows the central axis of the tip coil to be aligned with the central axis of the resin sleeve, preventing a step difference from occurring between the outer circumferential surface of the tip coil and the outer circumferential surface of the resin sleeve.

[0019] (5) In the guide wire of the present invention, it is preferable that the resin sleeve has a two-layer structure consisting of an inner layer made of polyimide and an outer layer made of polyether block amide.

[0020] With a guidewire of this configuration, having an outer layer made of polyether block amide can improve the kink resistance of the resin sleeve and improve the adhesion of the hydrophilic resin applied to the surface of the resin sleeve.

[0021] (6) In the guide wire of the present invention, the rearmost portion of the rear end of the tip coil may be a solder-free portion in which solder has not penetrated the interior.

[0022] With a guidewire of this configuration, for example, if the guidewire is removed while the resin sleeve is stuck in a narrowed blood vessel, the resin sleeve will move relative to the core wire toward the tip, and even if its tip surface tries to be displaced in the same direction, the compression spring characteristics of the rearmost part of the tip coil (the solder-free portion) can prevent this movement and also alleviate the compressive load on the resin sleeve that occurs when attempting to remove the guidewire.

[0023] (7) In the guide wire of the present invention, the rear end of the tip coil and the tip of the rear end coil may be formed as closed ends.

[0024] With a guidewire of this configuration, for example, when the guidewire is rotated (torque transmitted) while the resin sleeve is stuck in the narrowed portion of the blood vessel, interference between the rear end of the tip coil and the tip surface of the resin sleeve, and between the tip of the rear coil and the rear end surface of the resin sleeve can be prevented. [Effects of the Invention]

[0025] According to the guidewire of the present invention, no gap (step) is created between the resin sleeve and the rear end coil, which would hinder insertion into curved blood vessels or compatibility with other devices used in combination. Furthermore, during the manufacturing process (soldering of the rear coil), the heat generated during soldering does not cause the rear end of the resin sleeve to melt. Furthermore, even if the rear end surface of the resin sleeve is displaced toward the tip relative to the core wire, the tip of the rear end coil can be maintained in contact with the rear end surface of the resin sleeve. Furthermore, it prevents the rear end surface of the resin sleeve from being displaced in the rearward direction relative to the core wire, and also reduces the compressive load on the resin sleeve, thus preventing kinking or other damage to the resin sleeve. [Brief explanation of the drawing]

[0026] [Figure 1] This is an explanatory diagram showing a guide wire according to the first embodiment, with a portion of it broken off. [Figure 2] This is a magnified view of a portion of Figure 1 (detailed view of section A). [Figure 3] This is a magnified view of a portion of Figure 1 (detailed view of section B). [Figure 4] This is a photograph showing the main part of the guide wire according to the first embodiment. [Figure 5] Figure 1 is an explanatory diagram of the resin sleeve that constitutes the guide wire shown. [Figure 6] Figure 1 is an explanatory diagram of the compression coil spring that constitutes the tip coil of the guide wire, where (A) is a side view in the uncompressed state and (B) is a cross-sectional view in the uncompressed state. [Figure 7] Figure 1 is an explanatory diagram of the compression coil spring that constitutes the rear end coil of the guide wire, where (A) is a side view in the uncompressed state, (B) is a cross-sectional view in the uncompressed state, and (C) is a cross-sectional view in the fully compressed state. [Figure 8] Figure 1 is an explanatory diagram of the compression coil spring that constitutes the inner coil of the guide wire shown. [Figure 9] This is a schematic diagram illustrating a situation where a resin sleeve is trapped in a narrowed blood vessel, causing the guidewire to become stuck. [Figure 10] This is an explanatory diagram showing the main parts of the guide wire according to the second embodiment. [Figure 11] This is an explanatory diagram showing the main parts of the guide wire according to the third embodiment. [Figure 12] This photograph shows a gap formed between the sleeve and the rear-end coil that make up a conventional guide wire. [Modes for carrying out the invention]

[0027] <First Embodiment> The guide wire 100 of this embodiment, shown in Figures 1 to 3, consists of a core wire 10, a resin sleeve 20 rotatably arranged around the distal end small diameter portion 11 of the core wire 10, a compression coil spring having substantially the same outer diameter as the resin sleeve 20, a tip-side coil 30 positioned on the tip side of the resin sleeve 20 so as to surround the distal end small diameter portion 11 of the core wire 10, with its rear end in contact with the tip surface of the resin sleeve 20, a compression coil spring having substantially the same outer diameter as the resin sleeve 20, a rear-end side coil 40 positioned on the rear end side of the resin sleeve 20 so as to surround the distal end small diameter portion 11 of the core wire 10, with its tip in contact with the rear end surface of the resin sleeve 20, and the tip portion 31 of the tip-side coil 30 The device also includes an inner coil 50 made of a compression coil spring, which has a tip portion 51 fixed to the distal end small diameter portion 11 of the core wire 10 by solder 61, and a rear end portion 52 fixed to the distal end small diameter portion 11 of the core wire 10 by solder 64 inside the resin sleeve 20. The tip-side coil 30 is fixed to the distal end small diameter portion 11 of the core wire 10 by solder 61 and 62 at its tip portion 31 and rear end portion 32, respectively. The rear end-side coil 40 consists of a solder-penetrated rear end portion 42 into which solder 63 for fixing the rear end-side coil 40 to the distal end small diameter portion 11 of the core wire 10 has penetrated, and a solder-non-penetrated tip portion 41 into which such solder has not penetrated (is not soldered).

[0028] The guide wire 100 of this embodiment comprises a core wire 10, a resin sleeve 20, a front coil 30, a rear coil 40, and an inner coil 50.

[0029] The core wire 10 that constitutes the guide wire 100 has a large diameter portion 13 at the proximal end, a tapered portion 12 that decreases in diameter toward the tip (distal direction), and a small diameter portion 11 at the distal end that decreases in diameter in stages toward the tip. The distal end small diameter portion 11, the tapered portion 12, and the proximal end large diameter portion 13 are integrally constructed from the same wire material (for example, a round bar member).

[0030] The material of the core wire 10 is not particularly limited, and examples include stainless steel such as SUS316 and SUS304, gold, platinum, aluminum, tungsten, tantalum, or alloys thereof, nickel-titanium alloy, etc., but in this embodiment it is made of stainless steel. A water-repellent resin layer (not shown) is formed on the outer surface of the core wire 10. As the resin constituting the water-repellent resin layer, any resin used for medical purposes that possesses water-repellent properties can be used, and suitable resins include fluororesins such as PTFE.

[0031] Total length of guide wire 100 (L 100 The length is preferably between 1300 and 3500 mm, and a suitable example is 2015 mm. Also, the outer diameter (D) of the large diameter portion 13 on the proximal end side. 13 The diameter is preferably 0.25 to 0.46 mm, and a preferred example is 0.35 mm.

[0032] The maximum outer diameter of the distal end small-diameter portion 11 is not particularly limited as long as it is smaller than the inner diameter of the resin sleeve 20; a preferred example is 0.190 mm.

[0033] The resin sleeve 20 that constitutes the guide wire 100 is rotatably positioned around the small-diameter portion 11 at the distal end of the core wire 10.

[0034] As shown in Figure 5, the resin sleeve 20 has a two-layer structure consisting of an inner layer 21 made of polyimide and an outer layer 22 made of polyether block amide (PEBAX®). As shown in Figures 2 and 3, a hydrophilic resin layer 70 is formed on the surface of the resin sleeve 20. Such a resin sleeve 20 has an outer layer 22 made of polyether block amide, which provides superior kink resistance compared to conventional sleeves made of polyimide alone, and also provides superior adhesion of the hydrophilic resin layer 70 formed on the surface of the resin sleeve 20 (outer layer 22).

[0035] Length of resin sleeve 20 (L 20 The length is preferably between 100 and 500 mm, and a suitable example is 330 mm. Outer diameter (D) of resin sleeve 20 20 The width is preferably 0.200 to 0.460 mm, and a suitable example is 0.315 mm. Inner diameter (d) of resin sleeve 20 20 The width is preferably 0.100 to 0.360 mm, and a suitable example is 0.215 mm. The ratio of the thickness of the inner layer 21 to the thickness of the outer layer 22 is preferably 4:6 to 6:4, and in the preferred example shown in Figure 5, it is 5:5.

[0036] The tip coil 30, which constitutes the guide wire 100, is made of a compression coil spring as shown in Figure 6, and is positioned on the tip side of the resin sleeve 20 so as to surround the small diameter portion 11 at the distal end of the core wire 10. The rear end of the tip coil 30 is in contact with the tip surface of the resin sleeve 20.

[0037] The tip coil 30 is fixed to the small-diameter distal end portion 11 of the core wire 10 by solder 61 that has penetrated into the tip portion 31 and solder 62 that has penetrated into the rear end portion 32. In Figures 1 and 2, 611 is the tip formed by solder 61. As the solder 61 and solder 62 that penetrate into the inside of the tip portion 31 and the rear end portion 32, Au-Sn solder, Ag-Sn solder, etc. can be used.

[0038] The tip coil 30 has substantially the same outer diameter as the resin sleeve 20. Specifically, the outer diameter of the tip coil 30 is D 30When this is the case, (D 30 / D 20 The value of ) is 0.9 to 1.2, preferably 0.9 to 1.1. Outer diameter (D) of the tip coil 30 30 A suitable example of this is 0.34 mm. Inner diameter (d) of the tip coil 30 30 A suitable example of this is 0.22 mm.

[0039] The wire diameter of the tip coil 30 is preferably 0.050 to 0.080 mm, and a preferred example is 0.060 mm.

[0040] Length of the tip coil 30 [Length when fixed to the distal end small diameter portion 11 of the core wire 10 (L shown in Figure 2)] 30 The length of the length is preferably 20 to 80 mm, and a suitable example is 50 mm. The length (L) of the tip 31 through which the solder 61 has penetrated is 31 The diameter is preferably 0.3 to 1.0 mm, and a suitable example is 0.6 mm. The length (L) of the rear end 32 through which the solder 62 has penetrated is 32 The diameter is preferably 0.4 to 1.2 mm, and a suitable example is 0.8 mm.

[0041] As shown in Figure 6, the compression coil spring constituting the tip coil 30 has a coil pitch (p) in the portion that becomes the tip 31. 31 ) and the coil pitch (p 32 ) is the coil pitch (p) in the middle section. 30 It is formed to be much larger in comparison to ). This makes it easier for solder to penetrate into the interior of the tip portion 31 and the rear portion 32 during the soldering process in which the tip portion 30 (tip portion 31 and rear portion 32) is fixed to the distal end small diameter portion 11 of the core wire 10.

[0042] The free length of the compression coil spring constituting the tip coil 30 is preferably 20 to 80 mm, and a suitable example is 52 mm. The coil pitch (p) in the middle section of a compression coil spring 30 The diameter is preferably 0.05 to 0.12 mm, and a suitable example is 0.08 mm. The coil pitch (p) of the tip portion 31 31 ) and the coil pitch (p 32 The diameter is preferably 0.07 to 0.15 mm, and a preferred example is 0.095 mm.

[0043] The rear end coil 40, which constitutes the guide wire 100, is made of a compression coil spring as shown in Figure 7, and is positioned on the rear end side of the resin sleeve 20 so as to surround the small diameter portion 11 at the distal end of the core wire 10. The tip of the rear end coil 40 is in contact with (presses against) the rear end surface of the resin sleeve 20.

[0044] As shown in Figure 3, the rear end coil 40 consists of a solder-penetrated rear end portion 42 into which solder 63 for fixing the rear end coil 40 to the small diameter portion 11 at the distal end of the core wire has penetrated, and a solder-non-penetrated front end portion 41 into which such solder has not penetrated (is not soldered). In other words, the rear end coil 40 is fixed to the small diameter portion 11 at the distal end of the core wire 10 by solder 63 that has penetrated only into the solder-penetrated rear end portion 42. As the solder 63 that penetrates into the solder-penetrated rear end portion 42, Au-Sn solder, Ag-Sn solder, etc. can be used. The solder-free tip portion 41, where solder has not penetrated the interior, has compression spring characteristics due to the compression coil spring.

[0045] The rear end coil 40 has substantially the same outer diameter as the resin sleeve 20. Specifically, the outer diameter of the rear end coil 40 is D 40 When this is the case, (D 40 / D 20 The value of ) is 0.9 to 1.2, preferably 0.9 to 1.1. Outer diameter (D) of the rear end coil 40 40 The diameter is preferably 0.24 to 0.46 mm, more preferably 0.32 to 0.36 mm, and a preferred example is 0.34 mm. The inner diameter (d) of the rear end coil 40 40 The diameter is preferably 0.08 to 0.40 mm, more preferably 0.22 to 0.26 mm, and a preferred example is 0.24 mm.

[0046] The wire diameter of the rear end coil 40 is preferably 0.03 to 0.08 mm, and a preferred example is 0.050 mm.

[0047] Length of the rear end coil 40 [Length when fixed to the small diameter portion 11 at the distal end of the core wire 10 (L shown in Figure 3)] 40 The length of the length is preferably 1.0 to 3.0 mm, and a suitable example is 1.70 mm. Length (L) of the solder-non-penetrating tip 41 41 ) and the length (L) of the solder-impregnated end portion 42 42 The ratio of ) to is preferably 4:6 to 6:4, and in the preferred example shown in Figure 3, it is 5:5.

[0048] Length (L) of the solder-non-penetrating tip 41 41 The diameter is preferably 0.4 to 1.6 mm, and a preferred example is 0.85 mm.

[0049] Length (L) of the solder-non-penetrating tip 41 41 By having a diameter of 0.4 mm or more, a sufficient separation distance is ensured between the resin sleeve 20 and the solder-penetrated rear end 42. This ensures that the heat generated during soldering (formation of the solder-penetrated rear end) is not transferred to the rear end of the resin sleeve 20 during the manufacturing of the guide wire 100 (soldering process of the rear end coil 40), and the compression spring characteristics at the solder-non-penetrated tip 41 can be fully expressed. Also, the length (L) of the solder-non-penetrating tip 41 41Since the diameter is 1.6 mm or less, the rear end coil 40, including the solder-non-penetrating tip portion 41, can be securely fixed to the small-diameter distal end portion 11 of the core wire 10 by the solder-penetrating rear end portion 42.

[0050] Length (L) of the solder-impregnated end portion 42 42 The diameter is preferably 0.4 to 1.6 mm, and a preferred example is 0.85 mm.

[0051] Length (L) of the solder-impregnated end portion 42 42 By having a diameter of 0.4 mm or more, the rear end coil 40, including the solder-penetrated rear end 42, can be securely fixed to the small-diameter distal end portion 11 of the core wire 10 by the solder-penetrated rear end 42. Also, the length of the solder-impregnated end (L 42 By having a diameter of 1.6 mm or less, the heat generated during soldering (formation of the solder-penetrated rear end) in the manufacturing of the guide wire 100 (soldering process of the rear end coil 40) can be reliably prevented from being transferred to the rear end of the resin sleeve 20, and the compression spring characteristics and flexibility of the solder-non-penetrated tip portion 41 can be fully expressed.

[0052] Figure 7 is an explanatory diagram of the compression coil spring that constitutes the rear end coil 40, where (A) is a side view in the uncompressed state, (B) is a cross-sectional view in the uncompressed state, and (C) is a cross-sectional view in the fully compressed state.

[0053] The free length of this compression coil spring shown in Figure 7 (the length in the uncompressed state as shown in Figures (A) and (B)) is preferably 1.4 to 3.5 mm, and a preferred example is 2.0 mm. Free length (L) of the part that becomes the solder-non-penetrating tip 41 o The diameter is preferably 0.7 to 1.75 mm, and a suitable example is 1.0 mm.

[0054] The compressed length of this compression coil spring shown in Figure 7 (the length in the fully compressed state as shown in Figure (C)) is preferably 0.8 to 2.6 mm, and a preferred example is 1.42 mm. The contact length (L) of the part that becomes the solder-non-penetrating tip 41 S The diameter is preferably 0.4 to 1.3 mm, and a preferred example is 0.71 mm.

[0055] The coil pitch (p) of the compression coil spring shown in Figure 7(B) 40 The diameter is preferably 0.06 to 0.08 mm, and a preferred example is 0.07 mm.

[0056] In the compression coil spring that constitutes the rear end coil 40, the free length of the portion that becomes the solder-non-penetrating tip 41 is L o The contact length of that part is set to L S In this case, the length (L) of the solder-non-penetrating tip 41 41 ) is, formula:(L S +0.05mm)≦ L 41 ≤(L o It is preferable that the value is -0.1 mm.

[0057] Length (L) of the solder-non-penetrating tip 41 41 ) is (L o By being -0.1 mm or less, the compression coil spring (part) constituting the solder-non-penetrating tip 41 can be extended by at least 0.1 mm. Here, when the guidewire 100 is bent, such as when inserted into a curved blood vessel, the resin sleeve 20 moves relative to the core wire 10 in the direction of the tip, and the rear end face is displaced in the same direction. However, the amount of displacement of the rear end face of the resin sleeve 20 in the direction of the tip is usually within 0.1 mm, and the tip of the rear end coil 40 can sufficiently follow such displacement, and the state in which it abuts the rear end face of the resin sleeve 20 can be reliably maintained.

[0058] Length (L) of the solder-non-penetrating tip 41 41 ) is (L SBy being greater than +0.05mm, the compression coil spring (part) constituting the solder-non-penetrating tip 41 is capable of compression by at least 0.05mm. As a result, for example, as shown in Figure 9, when the guide wire 100 is pushed in while the resin sleeve 20 is stuck in the narrowed part of the blood vessel, the resin sleeve 20 moves relative to the core wire 10 toward the rear end, and even if the rear end face tries to be displaced in the same direction, the compression spring characteristics of the solder-non-penetrating tip 41 prevent this movement and sufficiently alleviate the compressive load on the resin sleeve 20 caused by pushing in the guide wire 100.

[0059] The inner coil 50 constituting the guide wire 100 is a compression coil spring having a tip portion 51 which is fixed to the distal end small diameter portion 11 of the core wire 10 together with the tip portion 31 of the tip coil 30 (i.e., by solder 61), and a rear end portion 52 which is fixed to the distal end small diameter portion 11 of the core wire 10 by solder 64 inside the resin sleeve 20, and is positioned in a space partitioned by the outer circumferential surface of the distal end small diameter portion 11 of the core wire 10, the inner circumferential surface of the tip coil 30 and the inner circumferential surface of the resin sleeve 20. For solder 64, Au-Sn type solder, Ag-Sn type solder, etc., can be used.

[0060] By positioning the inner coil 50 in this space, the central axis of the tip coil 30 and the central axis of the resin sleeve 20 can be aligned, thereby preventing a step difference from occurring between the outer surface of the tip coil 30 and the outer surface of the resin sleeve 20.

[0061] Outer diameter of inner coil 50 (D 50 ) is the inner diameter (d) of the tip coil 30. 30 It is preferable that the outer diameter (D) be slightly smaller than the outer diameter (D 50 A suitable example of this is 0.19 mm. Inner diameter of inner coil 50 (d 50) is larger than the outer diameter of the distal end small diameter portion 11 where the inner coil 50 is located, and the inner diameter (d 50 A suitable example of this is 0.12 mm. Length of the inner coil 50 [Length when fixed to the small diameter portion 11 at the distal end of the core wire 10 (L shown in Figure 2)] 50 The length of the length is preferably 60-70 mm, and a suitable example is 65 mm.

[0062] The wire diameter of the inner coil 50 is preferably 0.02 to 0.05 mm, and a suitable example is 0.035 mm.

[0063] The free length of the compression coil spring constituting the inner coil 50 is preferably 30 to 120 mm, and a suitable example is 70 mm. The coil pitch (p) of this compression coil spring 50 The diameter is preferably 0.025 to 0.08 mm, and a suitable example is 0.055 mm.

[0064] In the guide wire 100 of this embodiment, the tip of the rear end coil 40, which is made of a compression coil spring, abuts against (presses against) the rear end surface of the resin sleeve 20. Therefore, no gap is created between the resin sleeve 20 and the rear end coil 40 that would hinder insertion into curved blood vessels or compatibility with other devices used in combination. Furthermore, since the compression coil spring constituting the rear end coil 40 has substantially the same outer diameter as the resin sleeve 20, no step is created between the resin sleeve 20 and the rear end coil 40. Furthermore, during the manufacturing of the guide wire 100 (soldering process of the rear end coil 40), the length (L) of the solder-non-penetrating tip portion 41 from the rear end of the resin sleeve 20 is measured. 41 Since the rear end coil 40 is soldered (formation of the solder-penetrated rear end 42) at a position separated by a sufficient distance equivalent to ), the rear end of the resin sleeve 20 will not melt due to the heat generated during soldering.

[0065] Furthermore, even if the guide wire 100 is bent due to insertion into a curved blood vessel, causing the resin sleeve 20 to move relative to the core wire 10 in the tip direction and the rear end surface of the resin sleeve 20 to be displaced in the same direction, the compression spring characteristics of the solder-non-penetrating tip 41 cause the solder-non-penetrating tip 41 to extend, allowing the tip of the rear end coil 40 to follow the displacement, thus maintaining contact with the rear end surface of the resin sleeve 20.

[0066] Furthermore, as shown in Figure 9, when the resin sleeve 20 is stuck in the narrowed portion of the blood vessel and the guide wire 100 is pushed in, the resin sleeve 20 moves relative to the core wire 10 toward the rear end. Even if the rear end face tries to displace in the same direction, the compression spring characteristics of the solder-non-penetrating tip 41 prevent this movement and alleviate the compressive load on the resin sleeve 20 caused by pushing in the guide wire. As a result, kinks and other damage to the resin sleeve 20 are not generated.

[0067] <Second Embodiment> The guide wire 200 of this embodiment, whose main parts are shown in Figure 10, is the same as that of the first embodiment except that solder 62 does not penetrate into the interior of the rearmost portion 322 at the rear end 32 of the tip coil 30. According to the guidewire 200 of this embodiment, as shown in Figure 9, when attempting to pull out the guidewire 200 while the resin sleeve 20 is stuck in the narrowed portion of the blood vessel, the resin sleeve 20 moves relative to the core wire 10 toward the tip, and even if its tip surface tries to be displaced in the same direction, the compression spring characteristics of the rearmost portion 322 (solder-non-penetrating portion) of the tip coil 30 prevent this movement and also mitigate the compressive load on the resin sleeve 20 that occurs when attempting to pull out the guidewire 200. The length (L) of the last end portion 322 where the solder 62 has not penetrated the interior. 322 The diameter is preferably 0.5 to 1.5 mm, and a suitable example is 0.85 mm.

[0068] <Third Embodiment> The guide wire 300 of this embodiment, whose main parts are shown in Figure 11, is the same as in the first embodiment except that the rear end of the front coil 35 that abuts against the front surface of the resin sleeve 20 and the front end of the rear coil 45 that abuts against the rear end surface of the resin sleeve 20 are both formed as closed ends. According to side 300 of this embodiment, as shown in Figure 9, when the guidewire 300 is rotated (torque transmitted) while the resin sleeve 20 is stuck in the narrowed portion of the blood vessel, interference between the rear end of the tip coil 35 and the tip surface of the resin sleeve 20, and between the tip of the rear end coil 45 and the rear end surface of the resin sleeve 20 can be prevented. [Explanation of symbols]

[0069] 100 guide wires 10 core wires 11. Small diameter portion at the distal end 20 resin sleeves 21 Inner Layer 22 Outer layer 30. Tip coil 31 Tip 32 Rear end 322 End part 35. Tip coil 40 Rear end coil 41. Solder-free tip 42 Solder penetration rear end 45 Rear end coil 50 Inner coil 51 Tip 52 Rear end 61~64 Solder 611 Tip 70 Hydrophilic resin layer

Claims

1. Core wire (10) and A resin sleeve (20) is rotatably positioned around the small-diameter portion (11) at the distal end of the core wire (10), A compression coil spring having substantially the same outer diameter as the resin sleeve (20), positioned on the tip side of the resin sleeve (20) so as to surround the distal end small diameter portion (11) of the core wire (10), and the rear end of the tip coil (30) is in contact with the tip surface of the resin sleeve (20), The device comprises a rear-end coil (40) which is made of a compression coil spring having substantially the same outer diameter as the resin sleeve (20), and is positioned on the rear end side of the resin sleeve (20) so as to surround the distal end small diameter portion (11) of the core wire (10), with its tip in contact with the rear end surface of the resin sleeve (20), The tip coil (30) is fixed to the distal end small diameter portion (11) of the core wire (10) by solder (61, 62) at its tip portion (31) and rear end portion (32), respectively. The rear end coil (40) is a guide wire consisting of a solder-penetrated rear end (42) in which solder (63) has penetrated the interior for fixing the rear end coil (40) to the distal end small diameter portion (11) of the core wire (10), and a solder-non-penetrated tip (41) in which such solder has not penetrated the interior.

2. The outer diameter (D) of the rear end coil (40) 40 ) is 0.24 to 0.46 mm, and the length of the solder-non-penetrating tip portion (41) (L 41 ) is 0.4 to 1.6 mm, and the length of the solder-penetrated rear end (42) (L 42 The guide wire according to claim 1, wherein the diameter is 0.4 to 1.6 mm.

3. In the compression coil spring that constitutes the rear end coil (40), the free length of the portion that becomes the solder-non-penetrating tip (41) is L o The contact length of that part is set to L. S Therefore, the length (L) of the solder-non-penetrating tip portion (41) 41 The guide wire according to claim 2, wherein the following formula is satisfied. Formula: (L) S +0.05mm)≦ L 41 ≦(L) o -0.1 mm)

4. The tip portion (51) is fixed to the distal end small diameter portion (11) of the core wire (10), together with the tip portion (31) of the tip coil (30), Inside the resin sleeve (20), the rear end portion (52) is fixed to the distal end small diameter portion (11) of the core wire (10) by solder (64) and The guide wire according to claim 1, comprising an inner coil (50) made of a compression coil spring having

5. The guide wire according to any one of claims 1 to 4, wherein the resin sleeve (20) has a two-layer structure consisting of an inner layer (21) made of polyimide and an outer layer (22) made of polyether block amide.

6. The guide wire according to any one of claims 1 to 4, wherein the rearmost portion (322) of the rear end (32) of the tip coil (30) is a solder-non-permeable portion in which solder has not penetrated the interior.

7. The guide wire according to any one of claims 1 to 4, wherein the rear end of the front coil and the front end of the rear coil are formed as closed ends.

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