Balloon for balloon catheter

Abstract

Provided is a balloon for a balloon catheter in which the balloon can be easily folded and easily inserted into a body cavity or through the body cavity, and which can prevent the balloon from elongating in the longitudinal direction of the catheter.　The balloon catheter satisfies at least one among (1) and (2) below.　(1) A distal end-side tapered part (24) has a first section (610) having an inner protruding portion (61), and a second section (620) not having the inner protruding portion (61), and the distal end-side tapered part (24) has an outer protruding portion (62) on the entire region of the second section (620).　(2) A proximal end-side tapered part (22) has a first section (610) having an inner protruding portion (61) and a second section (620) not having the inner protruding portion (61), and the proximal end-side tapered part (22) has an outer protruding portion (62) on the entire region of the second section (620).

Description

Technical Field

[0001] The present invention relates to a balloon for a balloon catheter.

Background Art

[0002] The formation of a stenosis hardened by calcification or the like on the inner wall of a blood vessel causes diseases such as angina pectoris and myocardial infarction. As one of the treatments for these, there is an angioplasty in which a stenosis is expanded using a balloon catheter. Angioplasty is a minimally invasive treatment that does not require thoracotomy such as bypass surgery and is widely performed.

[0003] In angioplasty, it may be difficult to expand a stenosis hardened by calcification or the like with a general balloon catheter. In addition, a method of expanding a stenosis by placing an indwelling expansion device called a stent in the stenosis is also used. However, for example, in some cases, an ISR (In-Stent-Restenosis) lesion or the like may occur in which the neointima of the blood vessel grows excessively after this treatment and the blood vessel stenosis occurs again. In an ISR lesion, the neointima is soft and the surface is slippery, so with a general balloon catheter, the position of the balloon may shift from the lesion during balloon expansion, damaging the blood vessel.

[0004] Even for such calcified lesions and ISR lesions, there is a balloon catheter that can expand the stenosis. For the balloon catheter, a protrusion, blade, or scoring element for biting into the stenosis is provided on the balloon. For example, Patent Document 1 discloses a balloon catheter having a scoring element made of a polymer material with higher rigidity than the polymer material forming the balloon body, and the scoring element is flattened at one end and the other end of the balloon. Patent Document 2 discloses a scoring balloon structure in which the height of the scoring element decreases along the tapered shape of the balloon. Patent Document 3 discloses a balloon catheter in which the protruding amount of the protrusion arranged on the tapered portion at the tip side is larger than that of the protrusion arranged on the straight tube portion of the balloon. Patent Document 4 discloses a balloon catheter in which an outer protrusion is provided on the straight tube portion of the balloon and an inner protrusion is provided on the tapered portion.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Summary of the Invention

Problems to be Solved by the Invention

[0006] The balloon catheter is inserted into the body cavity in a contracted and folded state and delivered to the treatment site. In order to perform safe and appropriate treatment, it is required that the balloon catheter can be easily folded, and the insertion into the body cavity and the delivery to the treatment site within the body cavity can be easily performed. However, the conventional balloon catheter as described above has room for improvement in terms of the ease of folding the balloon, the ease of insertion into the insertion portion and the insertion through the body cavity, and preventing the balloon from expanding to normal blood vessels that are not the treatment target and causing damage, or suppressing the elongation of the balloon in the longitudinal axis direction to sufficiently expand the balloon in the radial direction and improve the treatment efficiency. Therefore, an object of the present invention is to provide a balloon for a balloon catheter that can be easily folded, can be easily inserted into the body cavity and inserted through the body cavity, and can prevent the elongation of the balloon in the longitudinal axis direction.

Means for Solving the Problems

[0007] One embodiment of the balloon for a balloon catheter of the present invention that can solve the above problems has a balloon body having an outer surface and an inner surface. The balloon body has a straight tube portion, a distal tapered portion located on the distal side of the straight tube portion, and a proximal tapered portion located on the proximal side of the straight tube portion, and is characterized by satisfying at least one of the following (1) and (2). (1) In the longitudinal axis direction of the balloon body, the distal tapered portion has a first portion having an inner protruding portion that protrudes radially inward of the inner surface of the balloon body and extends in the longitudinal axis direction of the balloon body, and a second portion that is the entire section excluding the first portion and does not have an inner protruding portion. The distal tapered portion has an outer protruding portion that protrudes radially outward of the outer surface of the balloon body and extends in the longitudinal axis direction of the balloon body in the entire section of the second portion. (2) In the longitudinal axis direction of the balloon body, the proximal tapered portion has a first portion having an inner protruding portion that protrudes radially inward from the inner surface of the balloon body and extends in the longitudinal axis direction of the balloon body, and a second portion that is the entire section excluding the first portion and does not have an inner protruding portion. The proximal tapered portion has an outer protruding portion that protrudes radially outward from the outer surface of the balloon body and extends in the longitudinal axis direction of the balloon body over the entire section of the second portion.

[0008] In the balloon for the balloon catheter, it is preferable that the outer protruding portion and the inner protruding portion are arranged at the same position in the circumferential direction of the balloon body.

[0009] In the balloon for the balloon catheter, it is preferable that the first portion is not provided closer to the straight tube portion side than the second portion.

[0010] In the balloon for the balloon catheter, in the longitudinal axis direction of the balloon body, when the end on the straight tube portion side of the distal tapered portion and the proximal tapered portion is set as the 0% position and the other end is set as the 100% position, it is preferable that the second portion is provided over a section from at least 0% to 10% of at least one of the distal tapered portion and the proximal tapered portion.

[0011] It is preferable that the balloon for the balloon catheter has an outer protruding portion over the entire section of the first portion.

[0012] In the balloon for the balloon catheter, it is preferable that the straight tube portion has an outer protruding portion. In this case, it is preferable that at least one of the following (1) and (2) is satisfied. (1) The outer protruding portion of the distal tapered portion and the outer protruding portion of the straight tube portion continuously extend in the longitudinal axis direction of the balloon body. (2) The outer protruding portion of the proximal tapered portion and the outer protruding portion of the straight tube portion continuously extend in the longitudinal axis direction of the balloon body.

[0013] In the balloon for the balloon catheter, when the end on the straight tube portion side of the distal tapered portion and the proximal tapered portion is set as the 0% position and the other end is set as the 100% position in the longitudinal axis direction of the balloon body, an outer protruding portion is provided in at least a section from the at least 20% position to the 80% position of at least one of the distal tapered portion and the proximal tapered portion. When the difference between the radius of the outer circle with the outer diameter of the balloon body as the radius and the radius of the circumscribed circle of the outer protruding portion sharing the center with the outer circle is defined as the height of the outer protruding portion in the radial direction of the balloon body, it is preferable that at least one of the following (1) and (2) is satisfied. (1) The height of the outer protruding portion at the 80% position of the distal tapered portion is the same as or lower than the height of the outer protruding portion at the 20% position of the distal tapered portion. (2) The height of the outer protruding portion at the 80% position of the proximal tapered portion is the same as or lower than the height of the outer protruding portion at the 20% position of the proximal tapered portion.

[0014] In the balloon for the balloon catheter, when the end on the straight tube portion side of the distal tapered portion and the proximal tapered portion is set as the 0% position and the other end is set as the 100% position in the longitudinal axis direction of the balloon body, an outer protruding portion is provided at the 60% position of at least one of the distal tapered portion and the proximal tapered portion. When the difference between the radius of the outer circle with the outer diameter of the balloon body as the radius and the radius of the circumscribed circle of the outer protruding portion sharing the center with the outer circle is defined as the height of the outer protruding portion in the radial direction of the balloon body, it is preferable that the height of the outer protruding portion at the 60% position is the same as or lower than the height of the outer protruding portion in the straight tube portion.

[0015] In the balloon for the balloon catheter, when the end on the straight tube portion side of the distal tapered portion and the proximal tapered portion is set as the 0% position and the other end is set as the 100% position in the longitudinal axis direction of the balloon body, an outer protruding portion is provided at least at the 40% position of at least one of the distal tapered portion and the proximal tapered portion. When the difference between the radius of the outer circle with the outer diameter of the balloon body as the radius and the radius of the circumscribed circle of the outer protruding portion sharing the center with the outer circle is defined as the height of the outer protruding portion in the radial direction of the balloon body, it is preferable that the height of the outer protruding portion at the 40% position is the same as or lower than the height of the outer protruding portion in the straight tube portion.

[0016] In the balloon for the balloon catheter, when the end on the straight tube portion side of the distal tapered portion and the proximal tapered portion is set as the 0% position and the other end is set as the 100% position in the longitudinal axis direction of the balloon body, a first portion is arranged in the section from at least the 80% position to the 100% position of at least one of the distal tapered portion and the proximal tapered portion. When the difference between the radius of the inner circle with the inner diameter of the balloon body as the radius and the radius of the inscribed circle of the inner protruding portion sharing the center with the inner circle is defined as the height of the inner protruding portion in the radial direction of the balloon body, it is preferable that at least one of the following (1) and (2) is satisfied. (1) The height of the inner protruding portion at the 90% position of the distal tapered portion is the same as or higher than the height of the inner protruding portion at the 80% position of the distal tapered portion. (2) The height of the inner protruding portion at the 90% position of the proximal tapered portion is the same as or higher than the height of the inner protruding portion at the 80% position of the proximal tapered portion.

[0017] In the balloon for the balloon catheter, it is preferable that the distal tapered portion has a first portion and a second portion, and the proximal tapered portion does not have an inner protruding portion. In this case, the balloon body has a proximal sleeve portion proximal to the proximal tapered portion, and it is preferable that the proximal sleeve portion and the proximal tapered portion have an outer protruding portion and do not have an inner protruding portion. Further, in this case, it is preferable that the outer protruding portion of the proximal sleeve portion and the outer protruding portion of the proximal tapered portion continuously extend in the longitudinal axis direction of the balloon body. Further, in this case, the straight tube portion has an outer protruding portion, and it is preferable that the outer protruding portion of the proximal tapered portion and the outer protruding portion of the straight tube portion continuously extend in the longitudinal axis direction of the balloon body.

[0018] In the balloon for the balloon catheter, it is preferable that the proximal tapered portion has a first portion and a second portion, and the distal tapered portion does not have an inner protruding portion.

[0019] In the balloon for the balloon catheter, it is preferable that the outer protruding portion and the inner protruding portion are made of the same material as the balloon body.

Advantages of the Invention

[0020] According to the balloon for the balloon catheter, when the balloon is contracted, it can be easily folded and the outer diameter of the balloon can be kept small. Therefore, insertion into the body cavity is facilitated and the followability when passing through the body cavity can be improved. For this reason, the time required for treatment using the balloon catheter can be shortened and the burden on the patient can be reduced. Further, the balloon for the balloon catheter can prevent the balloon from elongating in the longitudinal axis direction, such as when a fluid such as a pressurized fluid is introduced into the balloon to expand the balloon. By being able to prevent the balloon from elongating in the longitudinal axis direction, it becomes possible to expand the stenotic portion without the balloon expanding to a normal blood vessel that is not the treatment target and causing damage.

Brief Description of the Drawings

[0021]

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Mode for Carrying Out the Invention

[0022] Hereinafter, the present invention will be specifically described based on embodiments. However, the present invention is not limited by the following embodiments, and it is of course possible to appropriately modify and implement it within a range that conforms to the gist of the foregoing and following descriptions, and all of them are included in the technical scope of the present invention. In each drawing, for the sake of convenience, hatching, reference numerals of members, etc. may be omitted, but in such cases, reference shall be made to the specification and other drawings. Also, the dimensions of various members in the drawings may differ from the actual dimensions because priority is given to facilitating the understanding of the features of the present invention.

[0023] One embodiment of the balloon for a balloon catheter of the present invention has a balloon body having an outer surface and an inner surface. The balloon body has a straight tube portion, a distal tapered portion located on the distal side of the straight tube portion, and a proximal tapered portion located on the proximal side of the straight tube portion, and is characterized by satisfying at least one of the following (1) and (2). (1) In the longitudinal axis direction of the balloon body, the distal tapered portion has a first portion having an inner protruding portion that protrudes radially inward of the inner surface of the balloon body and extends in the longitudinal axis direction of the balloon body, and a second portion that is the entire section excluding the first portion and does not have an inner protruding portion. The distal tapered portion has an outer protruding portion that protrudes radially outward of the outer surface of the balloon body and extends in the longitudinal axis direction of the balloon body over the entire section of the second portion. (2) In the longitudinal axis direction of the balloon body, the proximal tapered portion has a first portion having an inner protruding portion that protrudes radially inward of the inner surface of the balloon body and extends in the longitudinal axis direction of the balloon body, and a second portion that is the entire section excluding the first portion and does not have an inner protruding portion. The proximal tapered portion has an outer protruding portion that protrudes radially outward of the outer surface of the balloon body and extends in the longitudinal axis direction of the balloon body over the entire section of the second portion. Thus, since at least one of the distal tapered portion and the proximal tapered portion has a first portion having an inner protrusion and a second portion that is the entire section excluding the first portion and does not have an inner protrusion, when the balloon is contracted, it can be easily folded and the outer diameter of the balloon can be kept small. Therefore, it is possible to provide a balloon for a balloon catheter that is easy to insert into a body cavity and has high followability when inserted through the body cavity. Further, since the first portion has an inner protrusion and the entire section of the second portion that does not have an inner protrusion has an outer protrusion, the balloon body is reinforced by the inner protrusion and the outer protrusion. Thus, it is possible to prevent elongation in the longitudinal axis direction of the balloon when a fluid such as a pressurized fluid is introduced into the balloon to expand the balloon. Hereinafter, the balloon for a balloon catheter may be simply referred to as a "balloon".

[0024] With reference to FIGS. 1 to 11, a balloon for a balloon catheter will be described. FIG. 1 shows a side view of a balloon catheter according to an embodiment of the present invention, and FIG. 2 shows a cross-sectional view in the longitudinal axis direction of the distal portion of the balloon catheter shown in FIG. 1. FIG. 3 shows a cross-sectional view taken along line III-III of FIG. 1, and FIG. 4 shows a cross-sectional view showing a modified example of FIG. 3. FIG. 5 shows a cross-sectional view taken along line V-V of FIG. 1, and FIG. 6 shows a cross-sectional view showing a modified example of FIG. 5. The shaft is omitted in FIGS. 3 to 6. FIG. 7 shows a cross-sectional view in the longitudinal axis direction of the distal portion of a balloon for a balloon catheter according to another embodiment of the present invention. FIGS. 8 to 11 show partially enlarged views of cross-sections in the longitudinal axis direction of the distal portion or the proximal portion of balloons according to different embodiments of the present invention. The shaft is omitted in FIGS. 8 to 11.

[0025] In the present invention, the proximal side refers to the direction on the side of the user or the operator with respect to the extending direction of the balloon catheter 1 or the longitudinal axis direction of the shaft 3, and the distal side refers to the direction opposite to the proximal side, that is, the direction on the side of the subject to be treated.

[0026] As shown in FIGS. 1 to 2, the balloon catheter 1 has a shaft 3 and a balloon 2 provided outside the shaft 3. The balloon catheter 1 has a proximal side and a distal side, and the balloon 2 is provided on the distal side of the shaft 3. The balloon catheter 1 is configured such that fluid is supplied into the balloon 2 through the shaft 3, and the inflation and deflation of the balloon 2 can be controlled using an inflator (balloon pressurizer). The fluid may be pressurized fluid pressurized by a pump or the like.

[0027] The shaft 3 preferably has a fluid flow path provided therein and further has an insertion passage for a guide wire. To configure the shaft 3 to have a fluid flow path and a guide wire insertion passage inside, for example, the shaft 3 has an outer tube 31 and an inner tube 32, the inner tube 32 functions as an insertion passage for the guide wire, and the space between the inner tube 32 and the outer tube 31 functions as a fluid flow path. When the shaft 3 has an outer tube 31 and an inner tube 32, it is preferable that the inner tube 32 extends from the distal end of the outer tube 31 and penetrates to the distal side of the balloon 2, the distal side of the balloon 2 is joined to the inner tube 32, and the proximal side of the balloon 2 is joined to the outer tube 31.

[0028] As shown in FIGS. 1 to 8, the balloon 2 for the balloon catheter 1 has a balloon body 20 having an outer surface and an inner surface. The balloon body 20 has a straight tube portion 23, a distal tapered portion 24 located on the distal side of the straight tube portion 23, and a proximal tapered portion 22 located on the proximal side of the straight tube portion 23, and satisfies at least one of the following (1) and (2). (1) In the longitudinal axis direction of the balloon body 20, the distal tapered portion 24 has a first portion 610 having an inner protruding portion 61 that protrudes radially inward from the inner surface of the balloon body 20 and extends in the longitudinal axis direction of the balloon body 20, and a second portion 620 that is the entire section excluding the first portion 610 and does not have the inner protruding portion 61. The distal tapered portion 24 has an outer protruding portion 62 that protrudes radially outward from the outer surface of the balloon body 20 and extends in the longitudinal axis direction of the balloon body 20 throughout the second portion 620. (2) In the longitudinal axis direction of the balloon body 20, the proximal tapered portion 22 has a first portion 610 having an inner protruding portion 61 that protrudes radially inward from the inner surface of the balloon body 20 and extends in the longitudinal axis direction of the balloon body 20, and a second portion 620 that is the entire section excluding the first portion 610 and does not have the inner protruding portion 61. The proximal tapered portion 22 has an outer protruding portion 62 that protrudes radially outward from the outer surface of the balloon body 20 and extends in the longitudinal axis direction of the balloon body 20 throughout the second portion 620. When at least one of the distal tapered portion 24 and the proximal tapered portion 22 has a second portion 620 that does not have an inner protruding portion 61 that inhibits the folding of the balloon 2 inside, the balloon 2 can be easily folded when the balloon 2 is contracted, and the outer diameter of the balloon 2 can be kept small. Also, since at least one of the distal tapered portion 24 and the proximal tapered portion 22 has an outer protruding portion 62 throughout the second portion 620 that does not have the inner protruding portion 61, the rigidity of the balloon 2 is ensured, and the elongation of the balloon 2 in the longitudinal axis direction, such as when a fluid such as a pressurized fluid is introduced into the balloon 2 to expand the balloon 2, can be prevented. As a result, the stenotic portion can be easily expanded, and the risk of the balloon 2 expanding to a normal blood vessel that is not the treatment target and causing damage can be reduced.

[0029] FIG. 2 shows an example in which both the distal tapered portion 24 and the proximal tapered portion 22 have a first portion 610 (a portion having the inner protrusion 61) and a second portion 620 (a section having the outer protrusion 62 in the entire section without the inner protrusion 61), but only the distal tapered portion 24 or only the proximal tapered portion 22 may have the first portion 610 and the second portion 620. At this time, the tapered portion that does not have the first portion 610 and the second portion 620 may have the outer protrusion 62 or may have the inner protrusion 61 in the entire section.

[0030] The distal tapered portion 24 and the proximal tapered portion 22 are preferably formed so as to have a reduced diameter as they move away from the straight tube portion 23. Since the balloon 2 has the straight tube portion 23 having the maximum diameter in the expanded state, the straight tube portion 23 can sufficiently contact the stenosis portion and easily expand the stenosis portion. Further, since the balloon 2 has the distal tapered portion 24 and the proximal tapered portion 22 whose outer diameter decreases as the balloon 2 moves away from the straight tube portion 23, when the balloon 2 is contracted and wound around the shaft 3, the outer diameters of the distal side and the proximal side of the balloon 2 can be reduced, and the step between the shaft 3 and the balloon 2 can be reduced. Therefore, the balloon 2 can be easily inserted into the body cavity.

[0031] As shown in FIG. 3, at least one of the distal tapered portion 24 and the proximal tapered portion 22 may have one inner protrusion 61 in the circumferential direction in the first portion 610, or may have a plurality of inner protrusions 61 in the circumferential direction as shown in FIG. 4. When having a plurality of inner protrusions 61 in the circumferential direction, it is preferable that the inner protrusions 61 are spaced apart in the circumferential direction, and more preferably, they are arranged at equal intervals in the circumferential direction. By at least one of the distal tapered portion 24 and the proximal tapered portion 22 having the inner protrusion 61 in this way, the elongation of the balloon 2 in the longitudinal axis direction can be prevented evenly in the circumferential direction.

[0032] As shown in Fig. 5, at least one of the distal tapered portion 24 and the proximal tapered portion 22 may have one outer protrusion 62 in the circumferential direction on the second portion 620, or may have a plurality of outer protrusions 62 in the circumferential direction as shown in Fig. 6. When there are a plurality of outer protrusions 62 in the circumferential direction, it is preferable that the outer protrusions 62 are spaced apart in the circumferential direction, and it is more preferable that they are arranged at equal intervals in the circumferential direction. By at least one of the distal tapered portion 24 and the proximal tapered portion 22 having such outer protrusions 62, the elongation of the balloon 2 in the longitudinal axis direction can be prevented evenly in the circumferential direction. Further, since the balloon 2 can be fixed to the stenosis portion or the stenosis portion can be incised by the outer protrusions 62, the outer protrusions 62 being spaced apart in the circumferential direction, preferably arranged at equal intervals, facilitates the fixation of the balloon 2 and the incision of the stenosis portion.

[0033] The shape of the cross-section perpendicular to the longitudinal axis direction of the inner protrusion 61 and the outer protrusion 62 may be any shape, may be a substantially triangular shape as shown in Figs. 3 to 6, or may be a polygon, a fan shape, a wedge shape, a convex shape, a spindle shape, etc. The maximum values of the heights of the inner protrusion 61 and the outer protrusion 62 in the first portion 610 and the second portion 620 respectively are preferably 1 times or more the film thickness of the balloon body 20, more preferably 1.5 times or more, still more preferably 2 times or more, and it is also acceptable to be 50 times or less, 30 times or less, or 10 times or less. By the maximum values of the heights of the inner protrusion 61 and the outer protrusion 62 in the first portion 610 and the second portion 620 respectively being within the above range, the elongation of the balloon 2 in the longitudinal axis direction can be prevented. The definition of the heights of the inner protrusion 61 and the outer protrusion 62 will be described later.

[0034] As shown in Fig. 2, it is preferable that the outer protrusion 62 and the inner protrusion 61 are arranged at the same position in the circumferential direction of the balloon body 20. Thereby, since the balloon 2 has the outer protrusion 62 that can reinforce the balloon body 20 from the outside and the inner protrusion 61 that can reinforce the balloon body 20 from the inside at the same position in the circumferential direction of the balloon body 20, the elongation of the balloon 2 in the longitudinal axis direction can be more easily prevented.

[0035] In the longitudinal axis direction of the balloon body 20, the end of the straight tube portion 23 side of the distal tapered portion 24 and the proximal tapered portion 22 is at the 0% position D0, and the other end is at the 100% position D 100 When this is the case, the section where the first part 610 is provided may be, for example, a section from the 90% position to the 100% position. As long as the first part 610 is provided at least in the above section, elongation in the longitudinal axis direction of the balloon 2 can be prevented. The section where the first part 610 is provided may be, for example, a section from the 80% position to the 100% position, a section from the 70% position to the 100% position, a section from the 60% position to the 100% position, a section from the 50% position to the 100% position, a section from the 40% position to the 100% position, a section from the 30% position to the 100% position, a section from the 20% position to the 100% position, or a section from the 10% position to the 100% position. If the section where the first part 610 is provided is within the above range, elongation in the longitudinal axis direction can be prevented, and since the entire section except the first part 610 is the second part 620 that does not have the inner protrusion 61, the balloon 2 can be made easily foldable.

[0036] As shown in FIG. 2, it is preferable that the first part 610 is not provided closer to the straight tube portion 23 side than the second part 620. That is, it is preferable that the second part 620 that does not have the inner protrusion 61 is provided in a portion adjacent to at least one of the straight tube portion 23 sides of the distal tapered portion 24 and the proximal tapered portion 22. By not providing the inner protrusion 61 inside the tapered portion adjacent to the straight tube portion 23 side where the folding margin becomes large, the balloon 2 can be folded more easily.

[0037] In the longitudinal axis direction of the balloon body 20, the end of the straight tube portion 23 side of the distal tapered portion 24 and the proximal tapered portion 22 is at the 0% position D0, and the other end is at the 100% position D 100When it is like this, it is preferable that the second part 620 is provided over an interval from at least 0% to 10% of the position of at least one of the distal tapered part 24 and the proximal tapered part 22. That is, it is preferable that the inner protruding part 61 is not provided in the interval from 0% to 10% of the position of at least one of the distal tapered part 24 and the proximal tapered part 22. It is more preferable that the second part 620 is provided over an interval from 0% to 15% of the position, and even more preferably, it is an interval from 0% to 20% of the position. Also, the second part 620 may be an interval from 0% to 90% of the position, or may be an interval from 0% to 80% of the position. Since the balloon 2 has the outer protruding part 62 in the entire second part 620 which is the entire interval except the first part 610, if the balloon 2 has the outer protruding part 62 in the entire first part 610, it is possible to have a configuration in which the outer protruding part 62 is provided in the entire interval of at least one of the distal tapered part 24 and the proximal tapered part 22 having the first part 610 and the second part 620. With such a configuration, the elongation of the balloon 2 in the longitudinal axis direction can be further suppressed.

[0038] The balloon 2 preferably has the outer protruding part 62 in the entire interval of the first part 610. Since the balloon 2 has the outer protruding part 62 in the second part 620 which is the entire interval except the first part 610, if the balloon 2 has the outer protruding part 62 in the entire first part 610, it is possible to have a configuration in which the outer protruding part 62 is provided in the entire interval of at least one of the distal tapered part 24 and the proximal tapered part 22 having the first part 610 and the second part 620. With such a configuration, the elongation of the balloon 2 in the longitudinal axis direction can be further suppressed.

[0039] At this time, it is preferable that the height of the outer protruding portion 62 provided on the first portion 610 is lower on the end side on the other side than on the end side on the straight tube portion 23 side of the first portion 610. With such a configuration, since the height of the outer protruding portion 62 is low on the side where the balloon 2 is more reduced in diameter, the outer diameter of the balloon 2 can be suppressed, making it easier to insert into the body cavity and enhancing the followability when passing through the body cavity. Even if the height of the outer protruding portion 62 is low in the portion including the end portion on the side opposite to the straight tube portion 23 of the first portion 610, since the first portion 610 has the inner protruding portion 61, the rigidity of the tapered portion can be ensured, and the elongation of the balloon 2 in the longitudinal axis direction can be prevented.

[0040] Alternatively, the balloon 2 may have an outer protruding portion 62 on a part of the first portion 610. In this case, the balloon 2 preferably has an outer protruding portion 62 in the portion including the end portion on the straight tube portion 23 side of the first portion 610 in the longitudinal axis direction of the balloon body 20, and does not have an outer protruding portion 62 in the portion including the end portion on the other side. With such a configuration, since the outer protruding portion 62 is not provided on the side where the balloon 2 is more reduced in diameter, the outer diameter of the balloon 2 can be suppressed, making it easier to insert into the body cavity and enhancing the followability when passing through the body cavity. Even if the outer protruding portion 62 is not provided in the portion including the end portion on the side opposite to the straight tube portion 23 of the first portion 610, since the balloon 2 has the inner protruding portion 61 on the first portion 610, the rigidity of the tapered portion can be ensured, and the elongation of the balloon 2 in the longitudinal axis direction can be prevented.

[0041] Also, at this time, it is preferable that the height of the outer protruding portion 62 provided on the first portion 610 is higher toward the straight tube portion 23 side of the first portion 610. Thereby, since the height of the outer protruding portion 62 is low on the side where the balloon 2 is more reduced in diameter, the outer diameter of the balloon 2 can be suppressed, making it easier to insert into the body cavity and enhancing the followability when passing through the body cavity.

[0042] As shown in Fig. 7, the straight tube portion 23 preferably has an outer protruding portion 62. Since the straight tube portion 23 having the maximum diameter in the expanded state of the balloon 2 has the outer protruding portion 62, the outer protruding portion 62 of the straight tube portion 23 facilitates the fixation of the balloon 2 and the incision of the stenosis portion.

[0043] As shown in Fig. 7, the balloon 2 preferably satisfies at least one of the following (1) and (2). (1) The outer protruding portion 62 of the distal tapered portion 24 and the outer protruding portion 62 of the straight tube portion 23 extend continuously in the longitudinal axis direction of the balloon body 20. (2) The outer protruding portion 62 of the proximal tapered portion 22 and the outer protruding portion 62 of the straight tube portion 23 extend continuously in the longitudinal axis direction of the balloon body 20. Fig. 7 shows an example in which the outer protruding portion 62 of the distal tapered portion 24, the outer protruding portion 62 of the straight tube portion 23, and the outer protruding portion 62 of the proximal tapered portion 22 extend in the longitudinal axis direction, that is, an example satisfying both (1) and (2) above. However, it is sufficient to satisfy at least one of (1) and (2) above. Since at least one of the distal tapered portion 24 and the proximal tapered portion 22 has the outer protruding portion 62, and the outer protruding portion 62 and the outer protruding portion 62 of the straight tube portion 23 extend continuously in the longitudinal axis direction of the balloon body 20, the elongation of the balloon 2 in the longitudinal axis direction can be further suppressed.

[0044] As shown in Fig. 8, in the longitudinal axis direction of the balloon body 20, the end on the straight tube portion 23 side of the distal tapered portion 24 and the proximal tapered portion 22 is at the 0% position D0, and the other end is at the 100% position D 100 When taken as such, the outer protruding portion 62 is provided in at least a 20% position D 20 to an 80% position D 80 of at least one of the distal tapered portion 24 and the proximal tapered portion 22. In the radial direction of the balloon body 20, the outer circle C o with the outer diameter of the balloon body 20 as the radius, the radius r o of the outer circle C o and the radius r of the circumscribed circle CC of the outer protruding portion 62 sharing the center P with the outer circle C ccThe difference from is the height t of the outer protrusion 62 o When this is the case, it is preferable that at least one of the following (1) and (2) is satisfied. (1) The height of the outer protrusion 62 at the 80% position of the distal tapered portion 24 is the same as or lower than the height of the outer protrusion 62 at the 20% position of the distal tapered portion 24. (2) The height of the outer protrusion 62 at the 80% position of the proximal tapered portion 22 is the same as or lower than the height of the outer protrusion 62 at the 20% position of the proximal tapered portion 22. When at least one of the distal tapered portion 24 and the proximal tapered portion 22 has a plurality of outer protrusions 62 in the circumferential direction, the position D of 80% of all the outer protrusions 62 80 The height at is the position D of 20% 20 It is preferable that the height is the same as or lower than the height at. By the outer protrusion 62 satisfying the above requirements, the height of the outer protrusion 62 on the more reduced-diameter side of the balloon 2 can be lowered to suppress the outer diameter of the balloon 2, facilitating insertion into the body cavity and enhancing the followability when passing through the body cavity. Also, even if the height of the outer protrusion 62 at the position D of 80% 80 is low, since the balloon 2 according to the embodiment of the present invention has the inner protrusion 61 in the first portion 610, the rigidity of the tapered portion can be ensured, and elongation of the balloon 2 in the longitudinal axis direction can be prevented.

[0045] Here, the method for measuring the height of the outer protrusion 62 will be described with reference to FIGS. 5 and 6. After introducing 5 atmospheres of UV curable resin into the balloon 2 and expanding it, UV is irradiated to cure the UV curable resin, and at a desired position in the longitudinal axis direction of the balloon body 20, for example, the position D of 20% in the above case 20 and the position D of 80% 80 The balloon body 20 is cut in the radial direction perpendicular to the longitudinal axis direction. The cut surface is observed using a microscope such as an optical microscope, and an outer circle C having the outer diameter of the balloon body 20 as the radius in the radial direction of the balloon body 20 o The radius r of o And the outer circle C o And the center The radius r of the circumscribed circle CC of the outer protruding portion 62 that shares P cc is obtained, and the radius r of the circumscribed circle CC cc subtracts the radius r of the outer circle C with the outer diameter of the balloon body 20 as the radius o from it, and the result is defined as the height t of the outer protruding portion 62 o For the UV curable resin, any resin can be used as long as it can be introduced into the balloon 2 and expanded o As shown in FIG. 9, in the longitudinal axis direction of the balloon body 20, the ends of the distal tapered portion 24 and the proximal tapered portion 22 on the straight tube portion 23 side are at the 0% position D0, and the other ends are at the 100% position D

[0046] When defined as such, the outer protruding portion 62 is provided at at least 60% of the position D of the distal tapered portion 24 and the proximal tapered portion 22 100 In the radial direction of the balloon body 20, the radius r of the outer circle C with the outer diameter of the balloon body 20 as the radius 60 subtracts the radius r of the circumscribed circle CC of the outer protruding portion 62 that shares the center P with the outer circle C o and the result is defined as the height t of the outer protruding portion 62 o When defined as such, the height of the outer protruding portion 62 at the 60% position D o is preferably the same as or lower than the height of the outer protruding portion 62 in the straight tube portion 23. When at least one of the distal tapered portion 24 and the proximal tapered portion 22 has a plurality of outer protruding portions 62 in the circumferential direction, at the 60% position D of all the outer protruding portions 62 CC the height of the outer protruding portion 62 at the 60% position D o is preferably the same as or lower than the height of the outer protruding portion 62 in the straight tube portion 23. When at least one of the distal tapered portion 24 and the proximal tapered portion 22 has a plurality of outer protruding portions 62 in the circumferential direction, at the 60% position D of all the outer protruding portions 62 60 the height of the outer protruding portion 62 at the 60% position D 60It is preferable that the height in [reference] is the same as or lower than the height of the outer protruding portion 62 in the straight pipe portion 23. By the outer protruding portion 62 satisfying the above requirements, the height of the outer protruding portion 62 on the side where the diameter is more reduced than the midpoint in the longitudinal axis direction of the tapered portion can be lowered to suppress the outer diameter of the balloon 2, facilitating insertion into the body cavity and enhancing the followability when passing through the body cavity. The outer protruding portion 62 of the portion of the tapered portion closer to the straight pipe portion 23 can also have a height equal to or higher than that of the outer protruding portion 62 in the straight pipe portion 23, so the outer protruding portion 62 in the tapered portion can also be used for fixing to the lesion or incision of the stenosis. Also, at the 60% position D 60 Even if the height of the outer protruding portion 62 at [reference] is low, since the balloon 2 according to the embodiment of the present invention has the inner protruding portion 61 in the first portion 610, the rigidity of the tapered portion can be ensured and the elongation of the balloon 2 in the longitudinal axis direction can be prevented.

[0047] As shown in FIG. 10, in the longitudinal axis direction of the balloon body 20, the ends of the straight pipe portions 23 of the distal tapered portion 24 and the proximal tapered portion 22 are at the 0% position D0, and the other ends are at the 100% position D 100 When set as such, at least one of the distal tapered portion 24 and the proximal tapered portion 22 has an outer protruding portion 62 at the 40% position D 40 In the radial direction of the balloon body 20, when the difference between the radius r o of the outer circle C o with the outer diameter of the balloon body 20 as the radius and the radius r o of the circumscribed circle CC of the outer protruding portion 62 that shares the outer circle C CC and the center P is defined as the height t o of the outer protruding portion 62, it is preferable that the height of the outer protruding portion 62 at the 40% position D 40 is the same as or lower than the height of the outer protruding portion 62 in the straight pipe portion 23. When at least one of the distal tapered portion 24 and the proximal tapered portion 22 has a plurality of outer protruding portions 62 in the circumferential direction, at the 40% position D of all the outer protruding portions 62 40It is preferable that the height in [reference numeral] is the same as or lower than the height of the outer protrusion 62 in the straight tube portion 23. By the outer protrusion 62 satisfying the above requirements, the height of the outer protrusion 62 can be reduced at the portion of the tapered portion closer to the straight tube portion 23, the outer diameter of the balloon 2 can be suppressed, the insertion into the body cavity can be made easier, and the followability when passing through the body cavity can be enhanced. Also, even if the height of the outer protrusion 62 at the position D of 40% 40 is low, since the balloon 2 according to the embodiment of the present invention has the inner protrusion 61 in the first portion 610, the rigidity of the tapered portion can be ensured, and the elongation of the balloon 2 in the longitudinal axis direction can be prevented.

[0048] As shown in FIG. 11, in the longitudinal axis direction of the balloon body 20, the end on the straight tube portion 23 side of the distal tapered portion 24 and the proximal tapered portion 22 is the position D0 of 0%, and the other end is the position D of 100% 100 When this is done, at least 80% of the position D of at least one of the distal tapered portion 24 and the proximal tapered portion 22 80 to the position D of 100% 100 The first portion 610 is arranged in the section up to, and in the radial direction of the balloon body 20, the inner circle C having the inner diameter of the balloon body 20 as the radius i The radius r of i And the inner circle C i When the difference from the radius r of the inscribed circle IC of the inner protrusion 61 sharing the center P is the height t of the inner protrusion 61 IC It is preferable that at least one of the following (1) and (2) is satisfied. i (1) The height of the inner protrusion 61 at the 90% position of the distal tapered portion 24 is the same as or higher than the height of the inner protrusion 61 at the 80% position of the distal tapered portion 24. (2) The height of the inner protrusion 61 at the 90% position of the proximal tapered portion 22 is the same as or higher than the height of the inner protrusion 61 at the 80% position of the proximal tapered portion 22. When at least one of the distal tapered portion 24 and the proximal tapered portion 22 has a plurality of inner protrusions 61 in the circumferential direction, the position D of 90% of all the inner protrusions 61 90The height is 80% at position D 80 It is preferable that the height of the inner protrusion 61 is equal to or higher than the height at the tapered portion on the straight tubular portion 23 side. By making the inner protrusion 61 satisfy the above requirements, the height of the inner protrusion 61 at the tapered portion on the side of the straight tubular portion 23 where the folding margin is greater can be reduced, making it possible to easily fold the balloon 2. Furthermore, since the height of the inner protrusion 61 can be increased at the end opposite the straight tubular portion 23 where the diameter of the tapered portion is smaller, the rigidity of the tapered portion in that area can be ensured and stretching of the balloon 2 in the longitudinal direction can be prevented.

[0049] Here, a method for measuring the height of the inner protrusion 61 will be described with reference to Figures 3 and 4. Similar to the method for measuring the height of the outer protrusion 62, a UV-curable resin at 5 atmospheres is introduced into the balloon 2 to expand it, and then UV is irradiated to harden the UV-curable resin, and the resin is measured at a desired position in the longitudinal axis direction of the balloon body 20, for example, the 80% position D in the above case. 80 and 90% position D 90 The balloon body 20 is cut in the radial direction perpendicular to the longitudinal axis direction with a cut surface. The cut surface is observed using a microscope such as an optical microscope, and an inner circle C having a radius equal to the inner diameter of the balloon body 20 in the radial direction of the balloon body 20 is identified. i radius r i and inner circle C i The radius r of the inscribed circle IC of the inner protrusion 61 which shares the center P with IC Find the radius r of the inscribed circle IC IC From the inner circle C whose radius is the inner diameter of the balloon body 20 i radius r i The difference between the height t of the inner protrusion 61 and the i Any resin can be used as the UV-curable resin as long as it can be introduced into the balloon 2 and expanded.

[0050] A balloon for a balloon catheter 2 according to still another embodiment of the present invention will be described with reference to Figures 12 and 13. Figures 12 and 13 each show a longitudinal cross-sectional view of the distal portion of a balloon catheter 1 according to a different embodiment.

[0051] As shown in FIG. 12, the distal tapered portion 24 has a first portion 610 and a second portion 620, and it is preferable that the proximal tapered portion 22 does not have an inner protruding portion 61. Since the distal tapered portion 24 has the second portion 620 that does not have an inner protruding portion 61 that inhibits the folding of the balloon 2 inside, when the balloon 2 is contracted, it can be easily folded and the outer diameter of the balloon 2 can be kept small. Since the outer diameter of the distal side of the balloon 2 can be kept small, the balloon catheter 1 can be easily advanced within the body cavity. Further, since the distal tapered portion 24 has an outer protruding portion 62 over the entire section of the second portion 620 that does not have an inner protruding portion 61, the rigidity of the balloon 2 can be ensured, and elongation in the longitudinal axis direction of the balloon 2 can be prevented when a fluid such as a pressurized fluid is introduced into the balloon 2 to expand the balloon 2. As a result, the stenosis can be easily expanded, and the risk of the balloon 2 expanding to a normal blood vessel that is not the treatment target and causing damage can be reduced. Further, as shown in FIG. 12, the proximal tapered portion 22 may have an outer protruding portion 62. By the proximal tapered portion 22 having an outer protruding portion 62, the rigidity of the balloon 2 in the proximal tapered portion 22 can be ensured, and elongation in the longitudinal axis direction of the balloon 2 can be prevented.

[0052] As shown in FIG. 13, the balloon body 20 has a proximal sleeve portion 21 on the proximal side of the proximal tapered portion 22. As described above, the distal tapered portion 24 has the first portion 610 and the second portion 620. When the proximal tapered portion 22 does not have the inner protrusion 61, it is preferable that the proximal sleeve portion 21 and the proximal tapered portion 22 have the outer protrusion 62 and do not have the inner protrusion 61. Since the proximal tapered portion 22 and the proximal sleeve portion 21 have the outer protrusion 62, the rigidity on the proximal side of the balloon 2 can be ensured, not only can the axial elongation of the balloon 2 be prevented, but also problems such as the balloon 2 being crushed when discharging fluid to contract the balloon 2 can be prevented. Further, since the proximal sleeve portion 21 does not have the inner protrusion 61, when the balloon 2 is expanded or contracted by introducing or discharging fluid into the balloon 2, the introduction or discharge of fluid can be performed in a shorter time, and the burden on the patient can be reduced.

[0053] In the above case, as shown in FIG. 13, it is preferable that the outer protrusion 62 of the proximal sleeve portion 21 and the outer protrusion 62 of the proximal tapered portion 22 extend continuously in the longitudinal axis direction of the balloon body 20. Since the outer protrusion 62 of the proximal sleeve portion 21 and the outer protrusion 62 of the proximal tapered portion 22 extend continuously in the longitudinal axis direction of the balloon body 20, the elongation in the longitudinal axis direction on the proximal side of the balloon 2 can be further suppressed.

[0054] Furthermore, as shown in FIG. 13, the straight tube portion 23 may have the outer protrusion 62. In this case, it is preferable that the outer protrusion 62 of the proximal tapered portion 22 and the outer protrusion 62 of the straight tube portion 23 extend continuously in the longitudinal axis direction of the balloon body 20. If the outer protrusion 62 extends continuously from the proximal sleeve portion 21 through the proximal tapered portion 22 to the straight tube portion 23, the elongation in the longitudinal axis direction from the straight tube portion 23 to the proximal side of the balloon 2 can be further suppressed.

[0055] As shown in FIG. 14, the balloon 2 for a balloon catheter may be configured such that the proximal tapered portion 22 has a first portion 610 and a second portion 620, and the distal tapered portion 24 does not have an inner protrusion 61. Since the proximal tapered portion 22 has the second portion 620 that does not have the inner protrusion 61 that inhibits the folding of the balloon 2 inside, the balloon 2 can be easily folded when the balloon 2 is contracted, and the outer diameter of the balloon 2 can be kept small. Since the outer diameter of the proximal side of the balloon 2 can be kept small, the balloon catheter 1 can be easily retracted when it is withdrawn from the body cavity. Further, since the proximal tapered portion 22 has the outer protrusion 62 over the entire section of the second portion 620 that does not have the inner protrusion 61, the rigidity of the balloon 2 can be ensured, and the elongation of the balloon 2 in the longitudinal axis direction can be prevented when a fluid such as a pressurized fluid is introduced into the balloon 2 to expand the balloon 2. Furthermore, since the distal tapered portion 24 does not have the inner protrusion 61, the balloon 2 can be easily folded also on the distal side. As shown in FIG. 14, the distal tapered portion 24 may have an outer protrusion 62. By the distal tapered portion 24 having the outer protrusion 62, the rigidity of the balloon 2 in the distal tapered portion 24 can be ensured, and the elongation of the balloon 2 in the longitudinal axis direction can be prevented. Furthermore, if the distal tapered portion 24 has the outer protrusion 62, it is effective for a treatment such as expanding while incising a lesion by gently advancing the balloon catheter 1.

[0056] Examples of the material constituting the balloon body 20 include polyolefin resins such as polyethylene, polypropylene, and ethylene-propylene copolymer; polyester resins such as polyethylene terephthalate and polyester elastomer; polyurethane resins such as polyurethane and polyurethane elastomer; polyphenylene sulfide resins; polyamide resins such as polyamide and polyamide elastomer; fluorine resins; silicone resins; and natural rubbers such as latex rubber. These may be used alone or in combination of two or more. Among them, polyamide resins, polyester resins, and polyurethane resins are preferably used. In particular, it is preferable to use an elastomer resin from the viewpoint of thinning the balloon body 20 and flexibility. For example, among polyamide resins, nylon 12, nylon 11, etc. are suitable as the resin constituting the balloon body 20, and nylon 12 is more suitable because it can be molded relatively easily when blow molding. Also, from the viewpoint of thinning the balloon body 20 and flexibility, polyamide elastomers such as polyether ester amide elastomer and polyamide ether elastomer are preferably used. Among them, polyether ester amide elastomer is preferably used because of its high yield strength and good dimensional stability of the balloon body 20.

[0057] The outer protrusion 62 and the inner protrusion 61 are preferably made of the same material as the balloon body 20. If the outer protrusion 62 and the inner protrusion 61 are made of the same material as the balloon body 20, it is possible to prevent the outer protrusion 62 and the inner protrusion 61 from easily damaging the outer surface of the balloon body 20 while maintaining the flexibility of the balloon 2. The balloon body 20, the outer protrusion 62, and the inner protrusion 61 are preferably integrally formed. Thereby, the outer protrusion 62 and the inner protrusion 61 can be prevented from falling off from the balloon body 20.

[0058] The balloon 2 can be manufactured by placing a tubular parison 200 made of resin, as shown in FIG. 15 for example, in a mold having grooves in its inner cavity and performing biaxial stretch blow molding. The outer protrusion 62 can be formed, for example, by inserting the parison 200 into the inner cavity of the mold, causing the thick portion 220 of the parison to enter the grooves of the mold, and introducing a fluid into the inner cavity 210 of the parison 200 to expand the parison 200. Further, the inner protrusion 61 can be formed, for example, by pressing the thick portion 220 of the parison 200 against a portion of the mold without grooves and introducing a fluid into the inner cavity 210 of the parison 200 to expand the parison 200. As the material constituting the parison 200, reference can be made to the description of the material constituting the balloon body 20 above.

[0059] Examples of the material constituting the shaft 3 include polyamide-based resins, polyester-based resins, polyurethane-based resins, polyolefin-based resins, fluorine-based resins, vinyl chloride-based resins, silicone-based resins, natural rubbers, and the like. These may be used alone or in combination of two or more. Among them, the material constituting the shaft 3 is preferably at least one of a polyamide-based resin, a polyolefin-based resin, and a fluorine-based resin. Thereby, the slipperiness of the surface of the shaft 3 can be enhanced, and the insertability of the balloon catheter 1 in the body cavity can be improved.

[0060] Examples of the joining of the balloon 2 and the shaft 3 include adhesion with an adhesive, welding, and caulking by attaching a ring-shaped member to a portion where the end of the balloon 2 and the shaft 3 overlap. Among them, the balloon 2 and the shaft 3 are preferably joined by welding. Since the balloon 2 and the shaft 3 are welded, the joining of the balloon 2 and the shaft 3 is less likely to be released even when the balloon 2 is repeatedly expanded and contracted, and the joining strength of the balloon 2 and the shaft 3 can be easily increased.

[0061] As shown in FIG. 1, a hub 4 may be provided on the proximal side of the shaft 3, and the hub 4 may be provided with a fluid injection portion 7 communicating with a flow path of fluid supplied into the balloon 2. Further, the hub 4 preferably has a guide wire insertion portion 5 communicating with an insertion path of a guide wire. Since the balloon catheter 1 has the hub 4 including the fluid injection portion 7 and the guide wire insertion portion 5, operations of supplying fluid into the balloon 2 to expand and contract the balloon 2, and operations of delivering the balloon catheter 1 along the guide wire to a treatment site can be easily performed. Thus, not only in a so-called over-the-wire type balloon catheter in which a guide wire is inserted from the distal side to the proximal side of the shaft, but also the balloon 2 according to an embodiment of the present invention can be applied to a so-called rapid exchange type balloon catheter in which a guide wire is inserted up to midway from the distal side to the proximal side of the shaft.

[0062] The joining of the shaft 3 and the hub 4 includes, for example, adhesion with an adhesive, welding, and the like. Among these, it is preferable that the shaft 3 and the hub 4 are joined by adhesion. By adhering the shaft 3 and the hub 4, for example, when the material constituting the shaft 3 is different from the material constituting the hub 4, such as the shaft 3 being made of a highly flexible material and the hub 4 being made of a highly rigid material, the joining strength between the shaft 3 and the hub 4 can be increased to enhance the durability of the balloon catheter 1.

[0063] This application claims the benefit of priority based on Japanese Patent Application No. 2020-190296 filed on November 16, 2020. The entire contents of the specification of Japanese Patent Application 2020-190296 filed on November 16, 2020 are incorporated herein by reference for reference.

Explanation of Reference Numerals

[0064] 1: Balloon catheter 2: Balloon 3: Shaft 4: Hub 5: Guide wire insertion portion 7: Fluid injection part 20: Balloon body 21: Proximal sleeve part 22: Proximal tapered part 23: Straight tube part 24: Distal tapered part 31: Outer tube 32: Inner tube 61: Inner protrusion 62: Outer protrusion 200: Parison 210: Inner cavity of parison 220: Wall thickness part of parison 610: First part 620: Second part C i : Inner circle with the inner diameter of the balloon body as the radius C o : Outer circle with the outer diameter of the balloon body as the radius r i : Radius of the inner circle with the inner diameter of the balloon body as the radius r o : Radius of the outer circle with the outer diameter of the balloon body as the radius IC: Inscribed circle of the inner protrusion CC: Circumscribed circle of the outer protrusion r IC : Radius of the inscribed circle of the inner protrusion r CC : Radius of the circumscribed circle of the outer protrusion D0: Position at 0% D 100 : Position at 100%

Claims

1. It has a balloon body having an outer surface and an inner surface, The balloon body has a straight tube portion, a distal tapered portion located distally of the straight tube portion, and a proximal tapered portion located proximally of the straight tube portion, A balloon for a balloon catheter, characterized by satisfying at least one of the following (1) and (2). (1) In the longitudinal axis direction of the balloon body, the distal tapered portion has a first portion having an inner protruding portion that protrudes radially inward of the inner surface of the balloon body and extends in the longitudinal axis direction of the balloon body, and a second portion that is the entire section excluding the first portion and does not have the inner protruding portion, The distal tapered portion has an outer protruding portion that protrudes radially outward of the outer surface of the balloon body and extends in the longitudinal axis direction of the balloon body in the entire section of the second portion, The distal tapered portion has the outer protruding portion in at least a part of the first portion, The outer protruding portion and the inner protruding portion are arranged at the same position in the circumferential direction of the balloon body, The first portion is not provided on the straight tube portion side of the second portion of the distal tapered portion. (2) In the longitudinal axis direction of the balloon body, the proximal tapered portion has a first portion having an inner protruding portion that protrudes radially inward of the inner surface of the balloon body and extends in the longitudinal axis direction of the balloon body, and a second portion that is the entire section excluding the first portion and does not have the inner protruding portion, The proximal tapered portion has an outer protruding portion that protrudes radially outward of the outer surface of the balloon body and extends in the longitudinal axis direction of the balloon body in the entire section of the second portion, The proximal tapered portion has the outer protruding portion in at least a part of the first portion, The outer protruding portion and the inner protruding portion are arranged at the same position in the circumferential direction of the balloon body, The first portion is not provided on the straight tube portion side of the second portion of the proximal tapered portion.

2. In the longitudinal axis direction of the balloon body, when the end on the straight tube portion side of the distal tapered portion and the proximal tapered portion is set as the 0% position and the other end is set as the 100% position, the second portion is provided over a section from at least the 0% position to the 10% position of at least one of the distal tapered portion and the proximal tapered portion. The balloon for a balloon catheter according to claim 1.

3. The balloon for a balloon catheter according to claim 1 or 2, having the outer protruding portion over the entire section of the first portion.

4. The balloon for a balloon catheter according to any one of claims 1 to 3, wherein the straight tube portion has the outer protruding portion.

5. The balloon for a balloon catheter according to claim 4, satisfying at least one of the following (1) and (2). (1) The outer protruding portion of the distal tapered portion and the outer protruding portion of the straight tube portion continuously extend in the longitudinal axis direction of the balloon body. (2) The outer protruding portion of the proximal tapered portion and the outer protruding portion of the straight tube portion continuously extend in the longitudinal axis direction of the balloon body.

6. In the longitudinal axis direction of the balloon body, when the end on the straight tube portion side of the distal tapered portion and the proximal tapered portion is set as the 0% position and the other end is set as the 100% position, the outer protruding portion is provided in a section from at least the 20% position to the 80% position of at least one of the distal tapered portion and the proximal tapered portion. In the radial direction of the balloon body, when the difference between the radius of the outer circle with the outer diameter of the balloon body as the radius and the radius of the circumscribed circle of the outer protruding portion sharing the center with the outer circle is defined as the height of the outer protruding portion. The balloon for a balloon catheter according to any one of claims 1 to 5, satisfying at least one of the following (1) and (2). (1) The height of the outer protruding portion at the 80% position of the distal tapered portion is the same as or lower than the height of the outer protruding portion at the 20% position of the distal tapered portion. (2) The height of the outer protruding portion at the 80% position of the proximal tapered portion is the same as or lower than the height of the outer protruding portion at the 20% position of the proximal tapered portion.

7. In the longitudinal axis direction of the balloon body, when the end on the straight tube portion side of the distal tapered portion and the proximal tapered portion is set as the 0% position and the other end is set as the 100% position, the outer protruding portion is provided at the 60% position of at least one of the distal tapered portion and the proximal tapered portion. In the radial direction of the balloon body, when the difference between the radius of the outer circle with the outer diameter of the balloon body as the radius and the radius of the circumscribed circle of the outer protruding portion sharing the center with the outer circle is defined as the height of the outer protruding portion. The balloon for a balloon catheter according to any one of claims 4 to 6, wherein the height of the outer protruding portion at the 60% position is the same as or lower than the height of the outer protruding portion in the straight tube portion.

8. In the longitudinal axis direction of the balloon body, when the end on the straight tube portion side of the distal tapered portion and the proximal tapered portion is set as the 0% position and the other end is set as the 100% position, the outer protruding portion is provided at the 40% position of at least one of the distal tapered portion and the proximal tapered portion. In the radial direction of the balloon body, when the difference between the radius of the outer circle with the outer diameter of the balloon body as the radius and the radius of the circumscribed circle of the outer protruding portion sharing the center with the outer circle is defined as the height of the outer protruding portion. The balloon for a balloon catheter according to any one of claims 4 to 6, wherein the height of the outer protruding portion at the 40% position is the same as or lower than the height of the outer protruding portion in the straight tube portion.

9. In the longitudinal axis direction of the balloon body, when the end on the straight tube portion side of the distal tapered portion and the proximal tapered portion is set as the 0% position and the other end is set as the 100% position, the first portion is arranged in the section from at least the 80% position to the 100% position of at least one of the distal tapered portion and the proximal tapered portion. In the radial direction of the balloon body, when the difference between the radius of the inner circle with the inner diameter of the balloon body as the radius and the radius of the inscribed circle of the inner protruding portion sharing the center with the inner circle is defined as the height of the inner protruding portion. The balloon for a balloon catheter according to any one of claims 1 to 8, satisfying at least one of the following (1) and (2). (1) The height of the inner protruding portion at the 90% position of the distal tapered portion is the same as or higher than the height of the inner protruding portion at the 80% position of the distal tapered portion. (2) The height of the inner protruding portion at the 90% position of the proximal tapered portion is the same as or higher than the height of the inner protruding portion at the 80% position of the proximal tapered portion.

10. The balloon for a balloon catheter according to any one of claims 1 to 9, wherein the distal tapered portion has the first portion and the second portion, and the proximal tapered portion does not have the inner protruding portion.

11. The balloon for a balloon catheter according to claim 10, wherein the balloon body has a proximal sleeve portion proximal to the proximal tapered portion, and the proximal sleeve portion and the proximal tapered portion have the outer protruding portion and do not have the inner protruding portion.

12. The balloon for a balloon catheter according to claim 11, wherein the outer protruding portion of the proximal sleeve portion and the outer protruding portion of the proximal tapered portion extend continuously in the longitudinal axis direction of the balloon body.

13. The balloon for a balloon catheter according to claim 11 or 12, wherein the straight tube portion has the outer protruding portion, and the outer protruding portion of the proximal tapered portion and the outer protruding portion of the straight tube portion extend continuously in the longitudinal axis direction of the balloon body.

14. The balloon for a balloon catheter according to any one of claims 1 to 9, wherein the proximal tapered portion has the first portion and the second portion, and the distal tapered portion does not have the inner protruding portion.

15. The balloon for a balloon catheter according to any one of claims 1 to 14, wherein the outer protruding portion and the inner protruding portion are made of the same material as the balloon body.

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