Balloon for balloon catheter

Abstract

Provided is a balloon for a balloon catheter such that it is possible to efficiently incise a lesioned part, while being able to easily fix a balloon to the lesioned part and prevent the shifting of the balloon from the lesioned part.　This balloon (2) has a balloon body (20) that has a straight tube part (23), a proximal-side tapered part (22), a proximal-side sleeve part (21), a distal-side tapered part (24), and a distal-side sleeve part (25), said balloon body (20) having a band-shaped region (40) which extends in the longitudinal axis direction (x). The band-shaped region (40) includes a first region (41) composed of a projecting part whose height from the outer surface of the balloon body (20) is (H), and a second region (42) whose height is less than (H). The first region (41) is disposed in the straight tube part (23), and the surface roughness of the second region (42) is greater than the surface roughness of the first region (41).

Description

[Technical Field]

[0001] This invention relates to a balloon for a balloon catheter. [Background technology]

[0002] Angina pectoris and myocardial infarction are caused by the formation of narrowed areas in the inner walls of blood vessels due to hardening caused by calcification, etc. One treatment for these conditions is angioplasty, which uses a balloon catheter to dilate the narrowed area. Angioplasty is a minimally invasive treatment that does not require open-heart surgery like bypass surgery, and is widely performed.

[0003] In angioplasty, conventional balloon catheters may have difficulty dilating stenotic areas hardened by calcification. Another method involves placing a stent, a device used to dilate the stenotic area. However, this treatment can sometimes lead to ISR (In-Stent-Restenosis) lesions, where excessive neointimal growth occurs, causing the vascular stenosis to recur. In ISR lesions, the neointimal growth is soft and slippery, which can cause the balloon to shift from the lesion during inflation with conventional balloon catheters, potentially damaging the blood vessel.

[0004] To dilate stenotic lesions such as calcified lesions and ISR lesions, balloon catheters have been developed that have protrusions, blades, or scoring elements on the balloon to engage with the stenotic area. For example, Patent Document 1 discloses a balloon catheter having a balloon with modified sections of different tensile strengths and a stopper with high frictional resistance on the outer surface of the balloon. Patent Document 2 also discloses a balloon catheter having a plurality of spaced-apart wedge-shaped cutting instruments, the cutting instruments having a predetermined shape. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2018-7810 [Patent Document 2] Special Publication No. 2018-528055 [Overview of the Initiative] [Problems that the invention aims to solve]

[0006] A balloon catheter is used to expand a lesion by transporting the balloon to a lesion such as a stenosis, fixing the balloon to the lesion, cutting the lesion with an incision means such as a protruding part, and then inflating the balloon. If the balloon is not properly fixed to the lesion, it may slip and shift away from the lesion, causing damage to blood vessels other than the lesion or preventing the lesion from expanding. For this reason, the above-mentioned Patent Documents 1 and 2 attempt to suppress balloon slippage by providing stoppers or wedge-shaped cutting instruments, but there was room for improvement in easily fixing the balloon to the lesion while efficiently cutting the lesion. Therefore, the present invention aims to provide a balloon for a balloon catheter that can be easily fixed to a lesion, suppresses displacement of the balloon from the lesion, and efficiently cuts the lesion. [Means for solving the problem]

[0007] One embodiment of the balloon for balloon catheters of the present invention that can solve the above problems is as follows. [1] A balloon for a balloon catheter, comprising a straight tube portion, a proximal tapered portion located proximal to the straight tube portion, a proximal sleeve portion located proximal to the proximal tapered portion, a distal tapered portion located distal to the straight tube portion, and a distal sleeve portion located distal to the distal tapered portion, wherein the balloon body has an outer surface and an inner surface, and the outer surface of the balloon body has a band-shaped region extending in the longitudinal direction of the balloon body, the band-shaped region comprising a first region consisting of a projection whose height from the outer surface of the balloon body is H in the radial cross-section of the balloon body, and a second region whose height from the outer surface of the balloon body is lower than H in the radial cross-section, the first region being located in the straight tube portion, and the surface roughness of the second region being greater than the surface roughness of the first region. The balloon body has a band-shaped region extending along its longitudinal axis on its outer surface. This band-shaped region includes a first region consisting of a protrusion with height H and a second region with height lower than H. The surface roughness of the second region is greater than that of the first region, allowing the balloon to be easily fixed to the stenosis. Furthermore, since the height H of the first region is greater than the height of the second region, the stenosis can be efficiently incised by the first region. As a result, the balloon catheter balloon according to the embodiment of the present invention prevents the balloon from shifting away from the stenosis, enabling easy and safe treatment.

[0008] The balloon for the balloon catheter according to the embodiment of the present invention is preferably one of the following [2] to

[10] . [2] The balloon for a balloon catheter according to [1], wherein the band-shaped region includes a transition region connecting the first region and the second region, and the surface roughness of the transition region is greater than that of the first region. [3] The balloon for a balloon catheter according to [1] or [2], wherein the second region is located in at least one of the proximal sleeve portion and the distal sleeve portion. [4] The balloon for a balloon catheter according to [3], wherein the band-shaped region further includes a third region in which the height from the outer surface of the balloon body in the radial cross-section is greater than the height H from the protrusion of the first region, and satisfies at least one of the following (1) and (2). (1) When the second region is located in the proximal sleeve portion, the height H of the protrusion in the proximal tapered portion gradually increases from the distal to the proximal side in the longitudinal axis direction of the balloon body. (2) When the second region is located in the distal sleeve portion, the height H of the protrusion in the distal tapered portion gradually increases from the proximal to the distal direction in the longitudinal axis direction of the balloon body. [5] A balloon for a balloon catheter as described in any of [1] to [4], satisfying at least one of (3) and (4) below. (3) The second region is arranged from the proximal sleeve portion to the proximal tapered portion. (4) The second region is arranged from the distal sleeve portion to the distal tapered portion. [6] The balloon for a balloon catheter according to any one of [1] to [5], wherein the second region is located in at least one of the proximal tapered portion and the distal tapered portion. [7] A balloon for a balloon catheter according to any of [1] to [6] that satisfies at least one of (5) and (6) below. (5) The second region is located from the proximal tapered portion to the proximal end of the straight pipe portion. (6) The second region is located from the distal tapered portion to the distal end of the straight pipe portion. [8] A balloon for a balloon catheter as described in [1] or [2], satisfying at least one of (7) and (8) below. (7) The second region is arranged from the proximal sleeve portion to the proximal tapered portion and further to the proximal end of the straight pipe portion. (8) The second region is arranged from the distal sleeve portion to the distal tapered portion and further to the distal end of the straight pipe portion. The balloon for a balloon catheter according to any one of [1] to [8], in which one or more of the second regions are arranged in the straight tube portion. The balloon for a balloon catheter according to any one of [1] to [9], in which the belt-like region includes a transition region connecting the first region and the second region, and one or more of the transition regions are arranged in the straight tube portion. The balloon for a balloon catheter according to any one of [1] to

[10] , in which the belt-like region has an inner protruding portion that protrudes inward in the radial direction from the inner surface of the balloon body in the radial cross section.

Advantages of the Invention

[0009] According to the balloon for a balloon catheter, the balloon body has a belt-like region extending in the longitudinal axis direction on the outer surface. The belt-like region includes a first region consisting of a protruding portion with a height of H and a second region with a height lower than H. Since the surface roughness of the second region is larger than the surface roughness of the first region, while fixing the balloon to the stenosis portion by the second region, the stenosis portion can be incised in the first region consisting of a protruding portion with a height higher than the second region. Thereby, according to the balloon for a balloon catheter, it is possible to prevent the balloon from slipping off the stenosis portion and to easily perform a safe treatment.

Brief Description of the Drawings

[0010] [Figure 1] It shows a side view of a balloon catheter according to an embodiment of the present invention. [Figure 2] It shows a plan view of the distal side including the balloon of the balloon catheter shown in FIG. 1. [Figure 3] It shows a cross-sectional view taken along line III-III of FIG. 2. [Figure 4] It shows a cross-sectional view taken along line IV-IV of FIG. 2. [Figure 5] It shows a cross-sectional view taken along line V-V of FIG. 2. [Figure 6] It shows a modified example of FIG. 3. [Figure 7]Represents a perspective view of the distal side of the balloon shown in FIG. 6. [Figure 8] Represents a modified example of FIG. 7. [Figure 9] Represents another modified example of FIG. 3. [Figure 10] Represents yet another modified example of FIG. 3. [Figure 11] Represents a radial cross-sectional view of a balloon according to still another embodiment of the present invention. [Figure 12] Represents a perspective view of a pre-inflation parison according to an embodiment of the present invention.

Mode for Carrying Out the Invention

[0011] 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 within the 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, member numbers, 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.

[0012] A balloon for a balloon catheter according to an embodiment of the present invention is a balloon for a balloon catheter having a straight tube portion, a proximal tapered portion located proximal to the straight tube portion, a proximal sleeve portion located proximal to the proximal tapered portion, a distal tapered portion located distal to the straight tube portion, and a distal sleeve portion located distal to the distal tapered portion, wherein the balloon body has an outer surface and an inner surface, and the outer surface of the balloon body has a band-shaped region extending in the longitudinal direction of the balloon body, the band-shaped region including a first region consisting of a projection whose height from the outer surface of the balloon body is H in a radial cross-section of the balloon body, and a second region whose height from the outer surface of the balloon body is lower than H in a radial cross-section, the first region being located in the straight tube portion, and the surface roughness of the second region being greater than that of the first region.

[0013] As described above, the balloon for a balloon catheter according to the embodiment of the present invention has a band-shaped region extending longitudinally on the outer surface of the balloon body. This band-shaped region includes a first region consisting of a protrusion with height H and a second region with height lower than H. The surface roughness of the second region is greater than that of the first region, so the balloon can be easily fixed to the stenosis by the rougher second region. Furthermore, since the height H of the first region consisting of the protrusion is higher than the height of the second region, the stenosis can be efficiently incised by the first region. In addition, since the surface roughness of the first region is less than that of the second region, the resistance when the protrusion of the first region bites into the stenosis is reduced, making it easier for the protrusion to incise the stenosis. As a result, with the balloon for a balloon catheter according to the embodiment of the present invention, the stenosis can be efficiently incised while preventing the balloon from shifting away from the stenosis, making it possible to perform safe and easy treatment.

[0014] The balloon for a balloon catheter according to an embodiment of the present invention will be described with reference to Figures 1 to 11. Figure 1 shows a side view of a balloon catheter according to one embodiment of the present invention. Figure 2 shows a distal plan view including the balloon of the balloon catheter shown in Figure 1. Figures 3 to 5 show cross-sectional views along line III-III, line IV-IV, and line VV in Figure 2, respectively. In Figures 4 and 5, the shaft (inner tube) is omitted. Figure 6 shows a modified example of Figure 3, i.e., a longitudinal cross-sectional view of the distal side including the balloon of a balloon catheter according to another embodiment of the present invention, and Figure 7 shows a distal perspective view of the balloon shown in Figure 6. Figure 8 shows a modified example of Figure 7, i.e., a perspective view of a balloon according to yet another embodiment of the present invention. Figures 9 and 10 show further modified examples of Figure 3, i.e., longitudinal cross-sectional views including the balloon of a balloon catheter according to yet another embodiment of the present invention. Figure 11 shows a radial cross-sectional view of a balloon according to yet another embodiment of the present invention. In this specification, the balloon for a balloon catheter may be simply referred to as "balloon".

[0015] In the present invention, the proximal side refers to the direction toward the user's proximal side 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 opposite direction of the proximal side, i.e., the direction toward the person being treated. Preferably, the longitudinal axis direction of the balloon catheter 1 is the same as the longitudinal axis direction x of the balloon body 20. In this specification, even if the member is not elongated, it will be described as having the same longitudinal axis direction x. The radial direction y of the balloon body 20 is the direction perpendicular to the longitudinal axis direction x and is the direction connecting the center of the balloon body 20 and a point on the outer edge of the balloon body 20 in a cross section perpendicular to the longitudinal axis direction x. The circumferential direction z of the balloon body 20 is the direction along the outer edge of the balloon body 20 in a cross section in the radial direction y.

[0016] As shown in Figure 1, the balloon catheter 1 has a shaft 3 and a balloon 2 provided at the distal end of the shaft 3. The balloon catheter 1 is configured so that fluid is supplied to the inside of the balloon 2 through the shaft 3, and the expansion and contraction of the balloon 2 can be controlled using an indefleror (balloon pressurizer). The fluid may be a pressurized fluid pressurized by a pump or the like.

[0017] Preferably, the shaft 3 has a fluid channel inside and also has a guide wire insertion passage. To configure the shaft 3 to have a fluid channel and a guide wire insertion passage inside, for example, as shown in Figure 1, the balloon catheter 1 is an over-the-wire type having a guide wire insertion passage extending from the distal to the proximal side of the shaft 3, and the shaft 3 has an outer tube 31 and an inner tube 32, with the inner tube 32 functioning as the guide wire insertion passage and the space between the inner tube 32 and the outer tube 31 functioning as a fluid channel. In this configuration where 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 distal to the balloon 2, with the distal side of the balloon 2 joined to the inner tube 32 and the proximal side of the balloon 2 joined to the outer tube 31.

[0018] Alternatively, although not shown in the figures, a balloon catheter 1 according to an embodiment of the present invention may be a rapid exchange type having a guidewire port midway from the distal to the proximal end of the shaft, and a guidewire insertion passage provided from the guidewire port to the distal end of the shaft. In this case, the balloon catheter preferably has an outer shaft and an inner shaft that functions as a guidewire insertion passage, and it is preferable that the space inside the outer shaft and outside the inner shaft functions as a fluid flow path. It is preferable that the inner shaft extends from the distal end of the outer shaft and penetrates the balloon, with the distal end of the balloon connected to the inner shaft and the proximal end of the balloon connected to the outer shaft.

[0019] As shown in Figures 1 to 5, the balloon 2 for the balloon catheter has a straight tube portion 23, a proximal tapered portion 22 located proximal to the straight tube portion 23, a proximal sleeve portion 21 located proximal to the proximal tapered portion 22, a distal tapered portion 24 located distal to the straight tube portion 23, and a distal sleeve portion 25 located distal to the distal tapered portion 24, and has an outer surface and an inner surface, and the outer surface of the balloon body 20 has a The balloon catheter 1 has a balloon body 20 having a band-shaped region 40 extending in the longitudinal axis direction x of the balloon body 20. The band-shaped region 40 includes a first region 41 consisting of a protruding portion 60 whose height from the outer surface of the balloon body 20 is H in a cross-section in the radial direction y of the balloon body 20, and a second region 42 whose height from the outer surface of the balloon body 20 is lower than H in a cross-section in the radial direction y. The first region 41 is located in the straight tube portion 23, and the surface roughness of the second region 42 is greater than that of the first region 41. With this configuration, when the balloon 2 of the balloon catheter 1 is delivered to the stenosis, the balloon 2 can be easily fixed to the stenosis by the rough surface of the second region 42. Furthermore, since the height H of the first region 41 consisting of the protruding portion 60 is higher than the height h of the second region 42, the stenosis can be efficiently incised by the first region 41. Furthermore, because the surface roughness of the first region is less than that of the second region, the resistance when the protrusion of the first region bites into the stenosis is reduced, making it easier for the protrusion to incise the stenosis. As a result, with balloon 2, the stenosis can be efficiently incised while preventing balloon 2 from shifting away from the stenosis, making it possible to perform treatment easily and safely.

[0020] As shown in Figures 1 to 3, the balloon 2 has a straight tube portion 23, a proximal tapered portion 22 located proximal to the straight tube portion 23, a proximal sleeve portion 21 located proximal to the proximal tapered portion 22, a distal tapered portion 24 located distal to the straight tube portion 23, and a distal sleeve portion 25 located distal to the distal tapered portion 24. At least a portion of the proximal sleeve portion 21 and the distal sleeve portion 25 can be fixed to the shaft 3. If the balloon catheter 1 is an over-the-wire type and the shaft 3 has an outer tube 31 and an inner tube 32, at least a portion of the proximal sleeve portion 21 can be fixed to the outer tube 31, and at least a portion of the distal sleeve portion 25 can be fixed to the inner tube 32. Alternatively, if the balloon catheter 1 is a rapid exchange type and the shaft 3 has an outer shaft and an inner shaft, then at least a portion of the proximal sleeve portion 21 can be fixed to the outer shaft, and at least a portion of the distal sleeve portion 25 can be fixed to the inner shaft.

[0021] The proximal tapered section 22, the straight section 23, and the distal tapered section 24 are parts that expand when fluid is supplied to the inside of the balloon 2 through the shaft 3, while it is preferable that the proximal sleeve section 21 and the distal sleeve section 25 do not expand even when fluid is supplied to the inside of the balloon 2. This allows for stable fixing of the balloon 2 to the shaft 3 even when the balloon 2 is expanded.

[0022] The straight tube section 23 preferably has the same diameter in the longitudinal axis direction x and is cylindrical in shape, while the proximal tapered section 22 and distal tapered section 24 are preferably formed to decrease in diameter as they move away from the straight tube section 23 and have a conical or frustoconical shape. Because the proximal tapered section 22 and distal tapered section 24 are tapered in diameter, when the balloon 2 is deflated, the outer diameters of the proximal and distal ends of the balloon 2 can be reduced, thereby reducing the step between the shaft 3 and the balloon 2, making it easier to insert the balloon 2 into the body cavity.

[0023] As shown in Figures 2 to 5, the balloon body 20 has an outer surface and an inner surface, and the outer surface of the balloon body 20 has a band-shaped region 40 extending in the longitudinal axis direction x of the balloon body 20. The band-shaped region 40 has a predetermined width in the circumferential direction z of the balloon body 20, and the width of the band-shaped region 40 is preferably 1 / 100 or more of the circumference of the balloon body 20, more preferably 1 / 80 or more, even more preferably 1 / 70 or more, and also preferably 1 / 4 or less, more preferably 1 / 8 or less, and even more preferably 1 / 10 or less. The balloon body 20 may have multiple band-shaped regions 40 in the circumferential direction z as shown in Figures 1 to 5, or it may have one band-shaped region 40, although this is not shown. When there are multiple band-shaped regions 40 in the circumferential direction z, the number of band-shaped regions 40 in the circumferential direction z is not particularly limited, but for example, 2 or more is preferred, 3 or more is more preferred, it may be 4 or more, and also preferably 10 or less, more preferably 8 or less, and it may be 6 or less. In this case, it is preferable that the band-shaped regions 40 are spaced apart in the circumferential direction z, and more preferably that they are spaced equally in the circumferential direction z. The equal spacing of the band-shaped regions 40 facilitates the fixation of the balloon 2 and the incision of the stenotic portion. The width range of the above-mentioned band-shaped regions 40 shall apply to the sum of the widths of all the band-shaped regions 40 if there are multiple such regions.

[0024] The band-shaped region 40 is preferably provided continuously from the proximal end to the distal end of the balloon body 20. Within the band-shaped region 40, the first region 41 and the second region 42 may be provided continuously or discontinuously.

[0025] The band-shaped region 40 may be arranged parallel to the longitudinal axis x, or it may be arranged spirally around the outer surface of the balloon body 20 in the circumferential direction z. If the band-shaped region 40 is arranged parallel to the longitudinal axis x, the balloon 2 can be fixed to the stenosis by the second region 42 of the band-shaped region 40, while the stenosis can be cut straight through by the first region 41. If the band-shaped region 40 is arranged spirally, the balloon 2 can be fixed to the stenosis by the second region 42 of the band-shaped region 40, while the stenosis can be cut diagonally through by the first region 41.

[0026] As shown in Figures 4 and 5, the band-shaped region 40 includes a first region 41 consisting of a protrusion 60 whose height from the outer surface of the balloon body 20 is H in a cross-section in the radial direction y of the balloon body 20, and a second region 42 whose height h from the outer surface of the balloon body 20 in a cross-section in the radial direction y is lower than the height H of the protrusion 60. Because the height H of the protrusion 60 in the first region 41 is higher than the height h of the second region 42, the balloon 2 can be easily cut by the first region 41 when it is delivered to the stenosis. In addition, because the first region 41 has a height H, it is possible to prevent the balloon 2 from stretching in the longitudinal axis direction x, and the first region 41 can prevent damage to blood vessels other than the stenosis. Furthermore, the pushability of the balloon 2 can be improved by the first region 41.

[0027] The cross-sectional shape of the projection 60 perpendicular to the longitudinal axis x may be any shape, and may be a roughly triangular shape as shown in Figure 4, for example, a triangle, quadrilateral, polygon, semicircle, part of a circle, roughly circular, sector, wedge, convex shape, spindle shape, and combinations thereof. Note that triangles, quadrilaterals, and polygons include not only those with clearly defined corner vertices and straight edges, but also so-called rounded polygons with rounded corners, and those with at least a portion of their edges being curved. Alternatively, the cross-sectional shape of the projection 60 may be an irregular shape with irregularities or notches. The maximum height H of the projection 60 is preferably 1 or more times the film thickness of the balloon body 20, more preferably 1.5 or more times, and even more preferably 2 or more times, and is also acceptable to be 50 or less, 30 or less, or 10 or less. Since the height H of the protruding portion 60 is within the above range, the incision of the stenosis by the first region 41 is made easier, the extension of the balloon 2 in the longitudinal axis direction x is easily prevented, and the pushability of the balloon 2 is also improved.

[0028] The method for measuring the height H of the protruding portion 60 will be explained with reference to Figure 4. After introducing a UV-curable resin at 5 atmospheres into the balloon 2 and expanding it, the UV-curable resin is cured by irradiation with UV light, and the balloon body 20 is cut in the radial direction y. The cut surface is observed using a microscope such as an optical microscope, and the outer circle C in the radial direction y has the outer diameter of the balloon body 20 as its radius is measured. o radius r o And outer circle C o The radius r of the circumscribed circle CC of the projection 60 that shares center P with cc Find the radius r of the circumscribed circle CC. cc From outer circle C o radius r o The height H of the protruding portion 60 is determined by subtracting the value of the protruding portion 60. Any UV-curable resin can be used as long as it can be introduced into the balloon 2 and expanded.

[0029] The height h of the second region 42 can also be determined in the same way as the height H of the protruding portion 60, as shown in Figure 5. The height h of the second region 42 should be lower than the height H of the first region 41, which consists of the protruding portion 60. Preferably, the height h of the second region 42 is 3 / 4 or less of the height H of the first region, more preferably 1 / 2 or less, and even more preferably 1 / 4 or less. The lower limit of the height h of the second region 42 may be 0, but a negative value, i.e., a configuration in which the outer surface of the portion of the balloon body 20 where the strip-shaped region 40 is located has a concave shape, is also acceptable.

[0030] The first region 41, consisting of the protruding portion 60, is located on the straight tube portion 23. The first region 41, consisting of the protruding portion 60, may also be located on the proximal tapered portion 22 and / or the distal tapered portion 23. By having the first region 41 located on the straight tube portion 23, the straight tube portion 23, which has the maximum diameter when the balloon 2 is expanded, is in sufficient contact with the stenosis, and the stenosis can be easily cut by the first region 41 located on the straight tube portion 23.

[0031] The surface roughness of the second region 42 is greater than that of the first region 41. The greater surface roughness of the second region 42 allows the balloon 2 to be easily fixed to the stenosis when it is delivered to the stenosis. Furthermore, the smaller surface roughness of the first region 41, which consists of the protrusion 60, makes it easier to cut into the calcified stenosis and plaque in the stenosis and to form cracks, thus allowing the stenosis to be expanded while preventing dissection of the vascular intima. The surface roughness of the second region 42 is preferably 1.1 times or more than that of the surface roughness of the first region 41, more preferably 1.25 times or more, and even more preferably 1.5 times or more, and is also acceptable to be 100 times or less, 20 times or less, or 10 times or less.

[0032] The surface roughness is the arithmetic mean roughness Ra between reference lengths of the roughness curve on the surface of the first region 41 or the second region 42. The above arithmetic mean roughness Ra corresponds to the arithmetic mean roughness Ra specified in JIS B0601 (2001) and is measured in accordance with JIS B0633 (2001). The reference length is as shown in JIS B0633 (2001). For measurement, a measuring instrument specified in JIS B0651 (2001) (for example, a laser microscope manufactured by Keyence Corporation, VK-9510) is used.

[0033] If the balloon body 20 has only one strip-shaped region 40, the surface roughness of the first region 41 and the second region 42 of the strip-shaped region 40 should be measured using the method described above. If the balloon body 20 has multiple strip-shaped regions 40 in the circumferential direction z, the surface roughness of the first region 41 and the second region 42 of any one of the strip-shaped regions should be measured using the method described above.

[0034] Methods for lowering the height h of the second region 42 to a lower height H of the first region 41 include, for example, removing the protrusions of the second region 42 using a laser, polishing the second region 42 with a polishing machine, and crushing the protrusions of the second region 42. Among these, the method of removing the protrusions of the second region 42 using a laser is preferred, and in this case, the use of a femtosecond laser with a short wavelength is more preferred. This is because, with a long wavelength laser, the temperature of the laser-processed surface rises and the resin of the second region 42 melts, whereas with a femtosecond laser, the melting of the resin of the second region 42 can be suppressed and the protrusions of the second region 42 can be removed. As a result, by using a femtosecond laser, it is possible to form a structure in the second region 42 with fine irregularities having a period in the longitudinal axis direction x, that is, a structure in which fine ridges and grooves parallel to the circumferential direction z are repeated, and the surface roughness of the second region 42 can be increased. Such a structure is preferable because it makes it easier to fix the balloon 2 to the constricted part by the second region 42.

[0035] As shown in Figure 5, the surface of the second region 42 is macroscopically flat, and it is preferable that fine irregularities are formed on this flat surface. This increases the area in which the second region 42 contacts the inner wall of the narrowed portion when the balloon 2 is delivered to the narrowed portion, making it easier to fix the balloon 2 by the second region 42.

[0036] As shown in the straight pipe section 23 in Figures 3 and 9, the first region 41 and the second region 42 in the strip-shaped region 40 may be formed with discontinuously different heights. This is preferable because it allows the balloon 2 to be fixed to the constricted portion even in the section where the height increases discontinuously from the second region 42 to the first region 41.

[0037] Alternatively, as shown in Figures 6 and 7, the band-shaped region 40 may include a transition region 43 connecting the first region 41 and the second region 42. In the transition region 43, it is preferable that the height increases continuously from the second region 42 to the first region 41. It is preferable that the surface roughness of the transition region 43 is greater than that of the first region 41. This allows the balloon 2 to be fixed to the narrowed area by the transition region 43. Furthermore, because the height increases continuously from the second region 42 to the first region 41 by the transition region 43, snagging can be suppressed when inserting the balloon 2 into the body cavity, making it easier to insert the balloon 2. The surface roughness of the transition region 43 can also be determined by the same measurement method as for the first region 41 and the second region 42.

[0038] The surface of the transition region 43 may be a flat slope when viewed macroscopically, a concave curved surface, or a convex curved surface. In any case, the above-mentioned effects can be achieved by the transition region 43.

[0039] Preferably, the second region 42 is located in at least one of the proximal sleeve portion 21 and the distal sleeve portion 25. If the second region 42 is located in both the proximal sleeve portion 21 and the distal sleeve portion 25, the balloon 2 can be fixed to the lesion by the second region 42 both when advancing and retracting the balloon 2. Alternatively, if the second region 42 is located only in the proximal sleeve portion 21, the balloon 2 can be fixed to the stenosis with its proximal end while the stenosis can be incised with the portion of the balloon 2 from the distal end to the dilator. In such cases, if the distal ends of the distal sleeve portion 25 and the distal tapered portion 24 have a protruding portion 60, it is effective for treatments in which the balloon catheter 1 is advanced by crawling to incise the lesion and dilate it. Alternatively, if the second region 42 is located only in the distal sleeve portion 25, the balloon 2 can be fixed to the stenosis with its distal end, so that treatment can be performed without the balloon 2 advancing unintentionally. Furthermore, the second region 42 may be located in a portion of the proximal sleeve portion 21 and / or the distal sleeve portion 25 in the longitudinal axis direction x, or it may be located along the entire longitudinal axis direction x.

[0040] As shown in Figure 8, the band-shaped region 40 further includes a third region 45 in the radial y-section of the balloon body 20, where the height from the outer surface of the balloon body 20 is higher than the height H of the protrusion 60 of the first region 41, and the second region 42 is located in at least one of the proximal sleeve portion 21 and the distal sleeve portion 25, it is preferable that at least one of the following conditions (1) and (2) is satisfied. (1) When the second region 42 is located in the proximal sleeve portion 21, at least a portion of the proximal tapered portion 22 includes the third region 45. (2) When the second region 42 is located in the distal sleeve portion 25, at least a part of the distal tapered portion 24 includes the third region 45. Although Figure 8 only shows the embodiment of (2) above, a similar configuration can be shown for (1) above. Also, Figure 8 shows an embodiment in which the distal sleeve portion 25 has a third region 45 whose height gradually increases from the protruding portion 60 of the first region 41 from the proximal to the distal side. However, the height of the third region 45 does not need to gradually increase; it is sufficient that the distal sleeve portion 25 has a third region 45 that is higher than the height H of the protruding portion 60 of the first region 41 in at least a part of it. The same applies to the proximal sleeve portion 21 in the case of (1).

[0041] In the tapered portion connected to the sleeve portion where the second region 42 is formed, the presence of a third region 45 that is higher than the height H of the protruding portion 60 allows the balloon 2 to be fixed to the constricted portion by the second region 42 of the sleeve portion, and also by the third region 45 of the tapered portion, thereby stabilizing the fixation of the balloon 2 through a synergistic effect. In this case, as shown in Figure 8, the strip-shaped region 40 may have a transition region 43 that connects the first region 41 and the third region 45. The transition region 43 makes it easier to fix the balloon 2 and also improves the ease of inserting the balloon 2. Thus, the transition region 43 may be located not only in the portion connecting the first region 41 and the second region 42, but also in the portion connecting the third region 45 and the first region 41.

[0042] The surface roughness of the third region 45 may be greater than that of the first region 41. This facilitates the fixation of the balloon 2 by the third region 45.

[0043] Alternatively, the surface roughness of the third region 45 may be less than that of the second region 42. In this case, the surface roughness of the third region 45 may be the same as that of the first region 41. Even if the surface roughness of the third region 45 is less than that of the second region 42, as with the first region 41, the third region 45 has a height greater than the height H of the protrusion 60 of the first region 41, which contributes to fixing the balloon 2 to the stenosis. Furthermore, if the surface roughness of the third region 45 is small, the resistance when the third region 45 bites into the stenosis is reduced, and the stenosis can also be incised by the third region 45.

[0044] Balloon 2 preferably satisfies at least one of the following conditions (3) and (4). (3) The second region 42 is arranged from the proximal sleeve portion 21 to the proximal tapered portion 22. (4) The second region 42 is arranged from the distal sleeve portion 25 to the distal tapered portion 24. If the second region 42 is located both from the proximal sleeve portion 21 to the proximal tapered portion 22 and from the distal sleeve portion 25 to the distal tapered portion 24, the balloon 2 can be fixed to the lesion by the second region 42 when advancing and retracting the balloon 2. Alternatively, if the second region 42 is located only from the proximal sleeve portion 21 to the proximal tapered portion 22, the balloon 2 can be fixed to the stenosis with its proximal end while the stenosis can be incised with the portion from the distal end to the dilated portion of the balloon 2. In such cases, if the distal ends of the distal sleeve portion 25 and the distal tapered portion 24 have protruding portions 60, it is effective for treatments in which the balloon catheter 1 is advanced by crawling to incise and dilate the lesion. Alternatively, if the second region 42 is located only from the distal sleeve portion 25 to the distal tapered portion 24, the balloon 2 can be fixed to the stenosis at its distal end, thus allowing treatment to be performed without the balloon 2 unintentionally advancing.

[0045] The second region 42 may be located in a portion of the proximal tapered portion 22 and / or the distal tapered portion 24 in the longitudinal axis direction x, or it may be located along the entire longitudinal axis direction x.

[0046] Preferably, the second region 42 is located in at least one of the proximal tapered portion 22 and the distal tapered portion 24. In this case, the second region 42 does not have to be located in the proximal sleeve portion 21 and the distal sleeve portion 25. This makes it possible to reduce the surface roughness of the proximal sleeve portion 21 and / or the distal sleeve portion 25, and while the balloon 2 is fixed to the stenosis by the second region 42 located in the tapered portion, the surface roughness of the tip portion when the balloon 2 is advanced or retracted can be reduced, making it easier to insert the balloon 2 into the body cavity.

[0047] As shown in Figures 3 and 6 to 8, when a second region 42 is formed in the tapered portion and the sleeve portion, it is preferable that one continuous second region 42 is formed. Alternatively, although not shown, two or more second regions 42 and transition regions 43 may be formed discontinuously in the tapered portion and the sleeve portion.

[0048] Balloon 2 preferably satisfies at least one of the following conditions (5) and (6). (5) The second region 42 is located from the proximal tapered portion 22 to the proximal end of the straight pipe portion 23. (6) The second region 42 is located from the distal tapered portion 24 to the distal end of the straight pipe portion 23. In this case, the second region 42 does not necessarily have to be located in the proximal sleeve portion 21 and the distal sleeve portion 25. This makes it possible to reduce the surface roughness of the proximal sleeve portion 21 and / or the distal sleeve portion 25, and while the balloon 2 is fixed to the stenosis by the second region 42 located from the tapered portion to the straight tube portion 23, the surface roughness of the tip portion when the balloon 2 is advanced or retracted can be reduced, making it easier to insert the balloon 2 into the body cavity. In addition, by having the second region 42 located at the proximal end and / or distal end of the straight tube portion 23, the balloon 2 can be fixed to the stenosis by the straight tube portion 23, which has the maximum diameter and can make sufficient contact with the stenosis, making the fixation of the balloon 2 more stable.

[0049] Balloon 2 preferably satisfies at least one of the following conditions (7) and (8). (7) The second region 42 is arranged from the proximal sleeve portion 21 to the proximal tapered portion 22 and further to the proximal end of the straight pipe portion 23. (8) The second region 42 is arranged from the distal sleeve portion 25 to the distal tapered portion 24 and further to the distal end of the straight pipe portion 23. This further improves the effect of fixing the balloon 2 to the stenosis by the second region 42. Also, if only condition (7) above is met, and the distal end of the distal sleeve portion 25 and distal tapered portion 24 has a protruding portion 60, it is effective for treatments in which the balloon catheter 1 is advanced by crawling to incise and dilate the lesion. Alternatively, if only condition (8) above is met, the balloon 2 can be fixed to the stenosis at its distal end, making it easy to retract the balloon 2 after treatment without the balloon 2 advancing unintentionally.

[0050] As shown in Figure 9, it is preferable that one or more second regions 42 are arranged in the straight pipe section 23. This allows the balloon 2 to be fixed to the constricted section by the second region 42 arranged in the straight pipe section 23, which has the maximum diameter and can sufficiently contact the constricted section. Furthermore, since a portion is formed in which the height increases discontinuously from the second region 42 to the first region 41, it is preferable that the balloon 2 can also be fixed to the constricted section in this portion. The number of second regions 42 formed in the straight pipe section 23 is one or more, more preferably two or more, even more preferably three or more, and may also be 10 or less, 8 or less, or 6 or less. The total length of the longitudinal axis x of the second regions 42 formed in the straight pipe section 23 is preferably 1 / 20 or more, more preferably 1 / 15 or more, even more preferably 1 / 10 or more, preferably 3 / 4 or less, more preferably 1 / 2 or less, and even more preferably 1 / 4 or less of the length of the longitudinal axis x of the straight pipe section 23.

[0051] As shown in Figure 10, it is preferable that one or more transition regions 43 are provided in the straight tube section 23. This allows the balloon 2 to be fixed to the narrowed portion by the second region 42 and the transition region 43, which are located in the straight tube section 23 that has the maximum diameter and can make sufficient contact with the narrowed portion. In addition, because the height increases continuously from the second region 42 to the first region 41 due to the transition region 43, snagging can be suppressed when inserting the balloon 2 into the body cavity, making it easier to insert the balloon 2.

[0052] As shown in Figures 9 and 10, in an embodiment in which one or more second regions 42 and transition regions 43 are arranged in the straight pipe section 23, it is preferable that the tapered section and / or sleeve section also have a second region 42 and a transition region 43. In this case, the second regions 42 and transition regions 43 arranged in the tapered section and / or sleeve section may be arranged in a continuous manner, as shown in Figures 9 and 10. Alternatively, although not shown, the tapered section and / or sleeve section may also have one or more second regions 42 or one or more second regions 42 and a transition region 43, similar to the straight pipe section 23. Alternatively, at least one of the proximal tapered section 22 and the distal tapered section 24 may have one or more second regions 42 or one or more second regions 42 and a transition region 43, and the sleeve section may have one second region 42 and a transition region 43.

[0053] In the above embodiment, as shown in Figure 10, a plurality of transition regions 43 formed in the straight tube section 23 may be formed adjacent to each other, and the protruding portion 60 of the straight tube section 23 may have a substantially V-shaped notch. In this case, the second region 42 can be understood as the boundary portion of the plurality of transition regions 43, that is, the substantially V-shaped bottom portion. With this configuration, the balloon 2 is fixed to the stenosis by the second region 42 and the transition region 43, while the incision of the stenosis by the protruding portion 60 of the first region 41 becomes easier.

[0054] As shown in Figure 11, it is preferable that the second region 42 of the strip-shaped region 40 has an inner projection 61 that protrudes radially y inward from the inner surface of the balloon body 20 and extends in the longitudinal axis direction x of the balloon body 20. This increases the rigidity of the second region 42, which has a height h lower than the height H of the first region 41, and is expected to prevent elongation of the balloon 2 in the longitudinal axis direction x and improve the pushability of the balloon 2. The inner projection 61 may or may not be formed in the first region 41.

[0055] Examples of materials that make up 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 resin; polyamide resins such as polyamide and polyamide elastomer; fluororesin, silicone resin, and natural rubber such as latex rubber. These may be used individually or in combination of two or more. Among these, polyamide resins, polyester resins, and polyurethane resins are preferably used. In particular, it is preferable to use elastomer resins from the viewpoint of thinning the balloon body 20 and improving its flexibility. For example, among polyamide resins, nylon 12 and nylon 11 are suitable as resins to make up the balloon body 20, and nylon 12 is more preferable because it can be molded relatively easily during blow molding. Furthermore, from the viewpoint of thinning the balloon body 20 and improving its flexibility, polyamide elastomers such as polyether ester amide elastomer and polyamide ether elastomer are preferably used. In particular, polyether ester amide elastomer is preferred because it has a high yield strength and provides good dimensional stability to the balloon body 20.

[0056] It is preferable that the protrusion 60 of the first region 41, the second region 42, and the inner protrusion 61 are made of the same material as the balloon body 20. If the protrusion 60 of the first region 41, the second region 42, and the inner protrusion 61 are made of the same material as the balloon body 20, the flexibility of the balloon 2 can be maintained while making it less likely for the protrusion 60, the second region 42, and the inner protrusion 61 to damage the outer surface of the balloon body 20. It is preferable that the balloon body 20, the protrusion 60, the second region 42, and the inner protrusion 61 are integrally molded. This prevents the protrusion 60, the second region 42, and the inner protrusion 61 from falling off the balloon body 20. Alternatively, the material forming the protrusion 60, the second region 42, and the inner protrusion 61 may be different from the material forming the balloon body 20, as long as it has a certain degree of compatibility with the material forming the balloon body 20.

[0057] The balloon 2 can be manufactured by placing a cylindrical parison 200 made of resin, as shown in Figure 12, into a mold having a groove in its lumen and forming it by biaxial stretch blow molding. The protrusion 60 can be formed, for example, by inserting the parison 200 into the lumen of the mold, causing the thicker portion 220 of the parison 200 to fit into the groove of the mold, and then introducing fluid into the lumen 210 of the parison 200 to inflate the parison 200. Subsequently, the protrusion 60 can be left as is in the first region 41, and the height h of the second region 42 can be made lower than the height H of the first region 41 by the method described above to form the second region 42. In addition, when forming the inner protrusion 61, for example, the thicker portion 220 of the parison 200 can be pressed against a part of the mold without a groove, and fluid can be introduced into the lumen 210 of the parison 200 to inflate the parison 200, thereby forming the second region 42 and the inner protrusion 61. For information on the materials that make up the parison 200, please refer to the description of the materials that make up the balloon body 20.

[0058] The shaft 3 is preferably composed of resin, metal, or a combination of resin and metal. Using resin as the constituent material of the shaft 3 makes it easier to impart flexibility and elasticity to the shaft 3. Using metal as the constituent material of the shaft 3 can improve the pushability of the balloon catheter 1. Examples of resins that constitute the shaft 3 include polyamide resins, polyester resins, polyurethane resins, polyolefin resins, fluororesins, vinyl chloride resins, silicone resins, and natural rubber. These may be used individually or in combination of two or more. In particular, it is preferable that the material constituting the shaft 3 be at least one of polyamide resins, polyolefin resins, and fluororesins, as this improves the slipperiness of the surface of the shaft 3 and improves the insertion of the balloon catheter 1 into the body cavity. Examples of metals that constitute the shaft 3 include stainless steel such as SUS304 and SUS316, platinum, nickel, cobalt, chromium, titanium, tungsten, gold, Ni-Ti alloy, Co-Cr alloy, or combinations thereof.

[0059] The shaft 3 may be a single shaft extending from the distal to the proximal end, or the shaft 3 may have a distal shaft and a proximal shaft made of separate members, with the proximal end of the distal shaft connected to the distal end of the proximal shaft to form the shaft 3. The distal shaft and the proximal shaft may be further composed of multiple tube members. If the shaft 3 is composed of a distal shaft and a proximal shaft, for example, both the distal shaft and the proximal shaft may be made of resin, or the distal shaft may be made of resin and the proximal shaft may be made of metal. The shaft 3 may also have a laminated structure made of different materials or the same material.

[0060] The balloon 2 and shaft 3 can be joined by adhesive bonding, welding, or by attaching a ring-shaped member to the overlapping portion of the balloon 2 end and shaft 3 and crimping it. Among these, it is preferable that the balloon 2 and shaft 3 are joined by welding. By welding the balloon 2 and shaft 3, the joint between the balloon 2 and shaft 3 is less likely to come undone even when the balloon 2 is repeatedly expanded and contracted, and the joint strength between the balloon 2 and shaft 3 can be easily increased.

[0061] Although not shown in the figures, it is preferable that a tip member is provided at the distal end of the balloon catheter 1. The tip member may be provided at the distal end of the balloon catheter 1 by being connected to the distal end of the balloon 2 as a separate component from the inner tube 32 or inner shaft, or the inner tube 32 or inner shaft extending distal to the distal end of the balloon 2 may function as the tip member.

[0062] On the inner tube 32 or inner shaft inside the balloon 2, radiopaque markers may be placed at the location of the balloon 2 in the longitudinal axis direction x, so that the position of the balloon 2 can be confirmed under X-ray fluoroscopy. Preferably, the radiopaque markers are placed at positions corresponding to both ends of the straight tube portion 23 of the balloon 2, or at a position corresponding to the center of the straight tube portion 23 in the longitudinal axis direction x.

[0063] As shown in Figure 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 section 7 that communicates with the fluid flow path supplied to the inside of the balloon 2. Furthermore, it is preferable that the hub 4 has a guidewire insertion section 5 that communicates with the guidewire insertion passage. Because the balloon catheter 1 has a hub 4 equipped with a fluid injection section 7 and a guidewire insertion section 5, operations such as supplying fluid to the inside of the balloon 2 to expand and deflate the balloon 2, and operations such as delivering the balloon catheter 1 to the treatment site along the guidewire can be easily performed. Thus, the balloon 2 according to the embodiment of the present invention can be applied not only to so-called over-wire type balloon catheters in which the guidewire is inserted from the distal side to the proximal side of the shaft, but also to so-called rapid-exchange type balloon catheters in which the guidewire is inserted partway from the distal side to the proximal side of the shaft. In the case of the rapid-exchange type, the guidewire insertion section is provided partway from the distal side to the proximal side of the shaft, so the hub 4 does not need to have a bifurcated structure.

[0064] The shaft 3 and the hub 4 can be joined by, for example, adhesive bonding or welding. Among these, it is preferable that the shaft 3 and the hub 4 are joined by adhesive bonding. By bonding the shaft 3 and the hub 4, the bonding strength between them can be increased, thereby improving the durability of the balloon catheter 1, especially when the materials constituting the shaft 3 and the hub 4 are different, such as when the shaft 3 is made of a highly flexible material and the hub 4 is made of a highly rigid material.

[0065] If the balloon catheter 1 is of the over-the-wire type, it is preferable that the outer wall of the outer tube 31 is appropriately coated. If it is of the rapid-exchange type, it is preferable that the outer wall of the distal shaft and / or proximal shaft is appropriately coated, and it is more preferable that both the distal and proximal shafts are coated.

[0066] The coating can be hydrophilic or hydrophobic depending on the purpose, and can be applied by immersing the shaft 3 in a hydrophilic or hydrophobic coating agent, applying a hydrophilic or hydrophobic coating agent to the outer wall of the shaft 3, or covering the outer wall of the shaft 3 with a hydrophilic or hydrophobic coating agent. The coating agent may contain chemicals or additives.

[0067] Examples of hydrophilic coating agents include hydrophilic polymers such as polyvinyl alcohol, polyethylene glycol, polyacrylamide, polyvinylpyrrolidone, and methyl vinyl ether maleic anhydride copolymer, or hydrophilic coating agents made from any combination thereof.

[0068] Examples of hydrophobic coating agents include polytetrafluoroethylene (PTFE), ethylene fluoride propylene (FEP), perfluoroalkoxyalkanes (PFA), silicone oil, hydrophobic urethane resins, carbon coatings, diamond coatings, diamond-like carbon (DLC) coatings, ceramic coatings, and substances with low surface free energy terminated with alkyl groups or perfluoroalkyl groups.

[0069] This application claims the benefit of priority based on Japanese Patent Application No. 2021-182088, filed on November 8, 2021. The entire specification of Japanese Patent Application No. 2021-182088, filed on November 8, 2021, is incorporated herein by reference. [Explanation of Symbols]

[0070] 1: Balloon catheter 2: Balloon 3: Shaft 4: Hub 5: Guide wire insertion part 7: Fluid injection part 20: Balloon body 21: Proximal sleeve part 22: Proximal taper part 23: Straight tube part 24: Distal taper part 25: Distal sleeve part 31: Outer tube 32: Inner tube 40: Band region 41: First region 42: Second region 43: Transition region 45: Third region 60: Protrusion 61: Inner protrusion 200: Parison 210: Lumen of parison 220: Wall thickness part of parison C O : Outer circle with the outer diameter of the balloon body as the radius CC: Circumscribed circle of the protrusion r o : Outer circle C o 's radius r CC : Radius of the circumscribed circle CC H: Height of the first region h: Height of the second region x: Longitudinal axis direction of the balloon body y: Diameter direction of the balloon body z: Circumferential direction of the balloon body

Claims

1. A balloon for a balloon catheter having a straight tube portion, a proximal tapered portion located proximal to the straight tube portion, a proximal sleeve portion located proximal to the proximal tapered portion, a distal tapered portion located distal to the straight tube portion, and a distal sleeve portion located distal to the distal tapered portion, A balloon body having an outer surface and an inner surface, wherein the outer surface of the balloon body has a band-shaped region extending in the longitudinal direction of the balloon body, The aforementioned band-shaped region includes a first region consisting of a protrusion whose height from the outer surface of the balloon body is H in the radial cross-section of the balloon body, and a second region whose height from the outer surface of the balloon body is lower than H in the radial cross-section. The first region is located in the straight pipe section, A balloon catheter balloon in which the surface roughness of the second region is greater than that of the first region.

2. The balloon for a balloon catheter according to claim 1, wherein the band-shaped region includes a transition region connecting the first region and the second region, and the surface roughness of the transition region is greater than that of the first region.

3. The balloon for a balloon catheter according to claim 1 or 2, wherein the second region is located in at least one of the proximal sleeve portion and the distal sleeve portion.

4. The aforementioned band-shaped region further includes a third region in which, in the radial cross-section, the height from the outer surface of the balloon body is greater than the height H of the protrusion in the first region. A balloon for a balloon catheter according to claim 3, satisfying at least one of the following (1) and (2). (1) When the second region is located in the proximal sleeve portion, at least a part of the proximal tapered portion includes the third region. (2) When the second region is located in the distal sleeve portion, at least a part of the distal tapered portion includes the third region.

5. A balloon for a balloon catheter according to claim 1 or 2, satisfying at least one of the following (3) and (4). (3) The second region is arranged from the proximal sleeve portion to the proximal tapered portion. (4) The second region is arranged from the distal sleeve portion to the distal tapered portion.

6. The balloon for a balloon catheter according to claim 1 or 2, wherein the second region is located in at least one of the proximal tapered portion and the distal tapered portion.

7. A balloon for a balloon catheter according to claim 1 or 2, satisfying at least one of the following (5) and (6). (5) The second region is located from the proximal tapered portion to the proximal end of the straight pipe portion. (6) The second region is located from the distal tapered portion to the distal end of the straight pipe portion.

8. A balloon for a balloon catheter according to claim 1 or 2, satisfying at least one of the following (7) and (8). (7) The second region is arranged from the proximal sleeve portion to the proximal tapered portion and further to the proximal end of the straight pipe portion. (8) The second region is arranged from the distal sleeve portion to the distal tapered portion and further to the distal end of the straight pipe portion.

9. The balloon for a balloon catheter according to claim 1 or 2, wherein one or more of the second regions are arranged in the straight tube portion.

10. The balloon for a balloon catheter according to claim 1 or 2, wherein the band-shaped region includes a transition region connecting the first region and the second region, and one or more of the transition regions are arranged in the straight tube portion.

11. The balloon for a balloon catheter according to claim 1 or 2, wherein the band-shaped region has an inner projection that protrudes radially inward from the inner surface of the balloon body in the radial cross-section.

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