catheter

Abstract

Ensure sufficient flexibility of the catheter. [Solution] The catheter comprises a tubular body and a resin layer. The tubular body is formed of fluororesin. The tubular body extends along its central axis. The outer surface of the tubular body has treated areas where the fluorine component has been removed and untreated areas where the surface treatment has not been applied. The resin layer is located on the outer surface of the tubular body.

Description

Technical Field

[0001] The technology disclosed in this specification relates to a catheter.

Background Art

[0002] A catheter is used, for example, when treating a lesion in a living body lumen such as a blood vessel. The catheter has, for example, a tubular body formed of a fluororesin and a resin layer disposed on the outer peripheral side of the tubular body.

[0003] For example, in order to improve the adhesiveness between the tubular body and the resin layer, a surface treatment for removing a fluorine component from the outer peripheral surface of the tubular body (hereinafter referred to as "defluorination treatment") is performed. In a known catheter, the degree of defluorination treatment is increased from the proximal end to the distal end of the tubular body (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] A known catheter cannot ensure sufficient flexibility and sufficient kink resistance.

[0006] This specification discloses a technology capable of solving the above-described problems.

Means for Solving the Problems

[0007] The technology disclosed in this specification can be realized, for example, in the following forms.

[0008] A catheter disclosed herein comprises a tubular body and a resin layer. The tubular body is formed of a fluororesin. The tubular body extends along a central axis. The outer surface of the tubular body has treated areas where the fluorine component has been removed and untreated areas where the surface treatment has not been applied. The resin layer is located on the outer surface of the tubular body. This configuration improves the flexibility and kink resistance of the catheter. [Brief explanation of the drawing]

[0009] [Figure 1] Explanatory diagram showing a longitudinal section of the catheter in the first embodiment. [Figure 2] Diagram illustrating the cross-section of the catheter at position II-II in Figure 1. [Figure 3] Side view of the tubular body in the first embodiment [Figure 4] Developed view of the tubular body in the first embodiment [Figure 5] An explanatory diagram showing a cross-section of the tubular body of the first embodiment at position VV in Figure 3. [Figure 6] This is an explanatory diagram showing a cross-section of the tubular body of the first embodiment at position VI-VI in Figure 3. [Figure 7] Diagram showing the results of the cantilever beam test. [Figure 8] Diagram showing the results of the tensile test. [Figure 9] Side view of the tubular body in the second embodiment [Figure 10] Side view of the tubular body in the third embodiment [Modes for carrying out the invention]

[0010] (First Embodiment) (Components of Catheter 100) Figure 1 is an explanatory diagram showing a longitudinal section (YZ section) of the catheter 100 in the first embodiment. Figure 1 shows a portion of the longitudinal section of the catheter 100 along the long axis. Figure 2 is an explanatory diagram showing a cross section (XY section) of the catheter 100 at position II-II in Figure 1.

[0011] The positive Z-axis side of catheter 100 is the distal end (tip) that is inserted into the body. The negative Z-axis side of catheter 100 is the proximal end (base) that is manipulated by the operator. In catheter 100 and its components, tip means the tip end, tip portion means the tip and its vicinity, base end means the proximal end, and proximal end portion means the base and its vicinity. In catheter 100 and its components, longitudinal section means a section parallel to the central axis Ax of catheter 100, and transverse section means a section perpendicular to the central axis Ax. The circumferential direction D1 of catheter 100 and its components means the direction along the outer circumference.

[0012] Catheter 100 is a tubular medical device with an open tip and a proximal end. Catheter 100 is used, for example, to treat a lesion. The cross-sectional shape of catheter 100 can be, for example, circular, partially circular, elliptical, rectangular, parallelogram, trapezoidal, or rhombic. The cross-sectional shape may differ depending on the part of catheter 100.

[0013] The catheter 100 includes a tubular body 40, a resin layer 50, and a reinforcing body 30.

[0014] The tubular body 40 is a tubular member with an open tip and base. The hollow portion of the tubular body 40 functions as a lumen S into which, for example, another medical device is inserted. The tubular body 40 extends along its central axis Ax.

[0015] The tubular body 40 is formed from a material containing fluororesin. Examples of materials for forming the tubular body 40 include polytetrafluoroethylene (PTFE), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), and tetrafluoroethylene-ethylene copolymer (ETFE). The entire tubular body 40 may be formed from the same material. The tubular body 40 may be formed from different materials in different parts.

[0016] The resin layer 50 is a tubular member with openings at both the tip and the base end. The resin layer 50 is disposed on the outer peripheral side of the tubular body 40. In the present embodiment, the inner peripheral surface of the resin layer 50 is in contact with the outer peripheral surface of the tubular body 40.

[0017] The resin layer 50 is formed of, for example, a resin material. Examples of the forming material of the resin layer 50 include polyamide-based resins, polyurethane-based resins, polyolefin-based resins, and the like. In the present embodiment, the resin layer 50 is formed of Pebax 40 (Pebax is a registered trademark of ARKEMA). The resin layer 50 may be entirely formed of the same material. The resin layer 50 may be formed of mutually different materials for each part.

[0018] The reinforcing body 30 is a tubular member with openings at both the tip and the base end. In the present embodiment, the reinforcing body 30 is a braided body in which a plurality of strands 32 are braided so as to cross each other. The reinforcing body 30 is continuously disposed from the base end to the tip of the catheter 100. The reinforcing body 30 is disposed between the tubular body 40 and the resin layer 50. More specifically, the reinforcing body 30 is disposed on the outer peripheral surface of the tubular body 40.

[0019] The reinforcing body 30 is formed of a metal material. Examples of the forming material of the reinforcing body 30 include tungsten, stainless steel (SUS302, SUS304, SUS316, etc.). The reinforcing body 30 may be entirely formed of the same material. The reinforcing body 30 may be formed of mutually different materials for each part.

[0020] (Detailed configuration of the tubular body 40) FIG. 3 is a side view of the tubular body 40 in the first embodiment. FIG. 4 is a developed view of the tubular body 40 in the first embodiment. A part of the outer peripheral surface of the tubular body 40 (hereinafter referred to as "treated portion S1") has been subjected to a defluorination treatment. The remaining part of the outer peripheral surface of the tubular body 40 (hereinafter referred to as "untreated portion S2") has not been subjected to a defluorination treatment.

[0021] Defluorination treatment is a process that removes fluorine components. Defluorination treatment is performed, for example, to suppress peeling of the resin layer 50 by improving the adhesion between the tubular body 40 and the resin layer 50.

[0022] Methods for defluorination treatment include, for example, chemical treatment of the outer surface of the tubular body 40, and physical treatment of the outer surface of the tubular body 40. Chemical treatment of the outer surface of the tubular body 40 includes, for example, immersion in a treatment tank containing a solution, and application of the solution to the outer surface of the tubular body 40. Solutions used in the chemical treatment of the outer surface of the tubular body 40 include, for example, alkali metal-containing solutions such as a mixed solution of sodium metal and ammonia, a mixed solution of sodium metal and tetrahydrofuran, and a mixed solution of sodium metal and naphthalene. Chemical treatment of the outer surface of the tubular body 40 changes the color of the surface to, for example, brown. Physical treatment of the outer surface of the tubular body 40 includes, for example, plasma treatment and corona discharge treatment. Physical treatment of the outer surface of the tubular body 40 physically roughens the outer surface of the tubular body 40. Therefore, the surface roughness of the tubular body 40 increases.

[0023] There are three methods for creating untreated areas S2. The first method involves covering a portion of the outer surface of the tubular body 40 before applying the defluorination treatment to the outer surface of the tubular body 40. The covered portion of the outer surface of the tubular body 40 will not be treated with defluorination. Therefore, the covered portion will become an untreated area S2. One method of covering is to use tape. The second method involves applying defluorination treatment locally to the outer surface of the tubular body 40. The portion of the outer surface of the tubular body 40 that has not been locally treated with defluorination will become an untreated area S2. The third method involves applying defluorination treatment to all of the outer surfaces of the tubular body 40, and then applying a treatment to reduce the effect of the defluorination treatment to a portion of the outer surface. The portion where the effect of the defluorination treatment is reduced will become an untreated area S2. One method of reducing the effect of the defluorination treatment is to apply heat.

[0024] When the outer surface of the tubular body 40 is chemically treated, the treated areas S1 and untreated areas S2 are distinguished, for example, by the color of the outer surface of the tubular body 40. The color of the treated areas S1 is, for example, reddish-brown. The color of the untreated areas S2 remains the same as the color of the outer surface of the tubular body 40 before chemical treatment. When the outer surface of the tubular body 40 is physically treated, the treated areas S1 and untreated areas S2 are distinguished, for example, by the surface roughness of the outer surface of the tubular body 40. The surface roughness of the treated areas S1 is above a predetermined threshold. The surface roughness of the untreated areas S2 is below the above threshold.

[0025] In this embodiment, the processed area S1 is formed by a plurality of annular regions RR aligned in the longitudinal direction and connecting regions CR connecting two adjacent annular regions RR. The annular regions RR and connecting regions CR are arranged along the entire length of the catheter 100. In this embodiment, the width of the annular regions RR in the longitudinal direction gradually increases from the tip to the proximal end of the tubular body 40. The positions of two adjacent connecting regions CR in the circumferential direction D1 are different from each other.

[0026] The distribution of treated areas S1 and untreated areas S2 on the outer surface of the tubular body 40 is as described above. Therefore, a virtual line VL can be drawn on the outer surface of the tubular body 40, parallel to the central axis Ax of the tubular body 40, and having a first virtual line segment LS1 and a second virtual line segment LS2. The second virtual line segment LS2 is located closer to the base end than the first virtual line segment LS1. The first virtual line segment LS1 and the second virtual line segment LS2 overlap the treated areas S1. The length of the second virtual line segment LS2 is longer than the length of the first virtual line segment LS1. In other words, the outer surface of the tubular body 40 has the first virtual line segment LS1 and the second virtual line segment LS2. The first virtual line segment LS1 and the second virtual line segment LS2 are located coaxially. The first virtual line segment LS1 and the second virtual line segment LS2 are parallel to the central axis Ax of the tubular body 40. The second virtual line segment LS2 is located closer to the base end than the first virtual line segment LS1. The first virtual line segment LS1 and the second virtual line segment LS2 overlap the processed area S1.

[0027] The tubular body 40 in this embodiment has a cross-section that includes multiple untreated areas S2. For example, the cross-section of the tubular body 40 at the position of the dashed line CS1 in Figure 4 includes two untreated areas S2.

[0028] The tubular body 40 of this embodiment has a first portion P1, a second portion P2 located closer to the base end than the first portion P1, a third portion P3 located closer to the base end than the second portion P2, and a fourth portion P4 located closer to the base end than the third portion P3. The first portion P1 and the second portion P2 are adjacent to each other. The second portion P2 and the third portion P3 are adjacent to each other. The third portion P3 and the fourth portion P4 are adjacent to each other. The outer circumferential surfaces of the first portion P1 and the third portion P3 have one untreated area S2 and one treated area S1 adjacent to the untreated area S2 in the circumferential direction. The outer circumferential surfaces of the second portion P2 and the fourth portion P4 have one treated area S1. In the circumferential direction D1 of the tubular body 40, the position of the treated area S1 of the first portion P1 and the position of the treated area S1 of the third portion P3 are different from each other.

[0029] Figure 5 is an explanatory diagram showing a cross-section of the tubular body 40 of the first embodiment at position VV in Figure 3. Figure 6 is an explanatory diagram showing a cross-section of the tubular body 40 of the first embodiment at position VI-VI in Figure 3.

[0030] In this embodiment, in at least one of the first portion P1 and the third portion P3, the length of the untreated portion S2 in the circumferential direction D1 is longer than the length of the treated portion S1 in the circumferential direction D1. That is, the length W2 of the untreated portion S2 in the first portion P1 is longer than the length W1 of the treated portion S1 in the first portion P1 in the circumferential direction D1. The length W4 of the untreated portion S2 in the third portion P3 is longer than the length W3 of the treated portion S1 in the third portion P3 in the circumferential direction D1. The angle α that the untreated portion S2 of the first portion P1 occupies with respect to the outer circumference and the angle β that the untreated portion S2 of the third portion P3 occupies with respect to the outer circumference are, for example, 190 degrees or more and 350 degrees or less. The angles α and β may also be 185 degrees or more and 355 degrees or less, or 210 degrees or more and 330 degrees or less. The angles α and β may be the same as each other or may be different from each other.

[0031] In this embodiment, as shown in Figure 3, the first boundary surface B1 between the first part P1 and the second part P2, and the second boundary surface B2 between the second part P2 and the third part P3 are parallel to each other. The first boundary surface B1 and the second boundary surface B2 are inclined with respect to a virtual plane VS perpendicular to the central axis Ax of the tubular body 40. The angle θ formed by the first boundary surface B1 and the second boundary surface B2 with respect to the central axis Ax is, for example, 10 degrees or more and 170 degrees or less. The above angle θ may also be 20 degrees or more and 160 degrees or less, or 30 degrees or more and 150 degrees or less.

[0032] (Performance evaluation) Three catheter samples, SA1 to SA3, were prepared, and a cantilever beam test was performed on these samples. Figure 7 shows the results of the cantilever beam test. Sample SA1 is the catheter 100 of the first embodiment. Sample SA2 is a catheter in which the entire outer surface of the tubular body has been defluorinated (hereinafter referred to as the "fully surface-treated catheter"). Sample SA3 is a catheter in which the outer surface of the tubular body has not been defluorinated at all (hereinafter referred to as the "untreated catheter"). In each sample, the tubular body 40 is formed from polytetrafluoroethylene (PTFE), and the resin layer 50 is formed from Pebax 40 (Pebax is a registered trademark of ARKEMA). The cantilever beam test was performed as follows.

[0033] When the lifting distance is LX, the load LW1 of sample SA1 is smaller than the load LW2 of sample SA2. Sample SA1 is more easily bent radially than sample SA2 because the treated area S1 and the untreated area S2 are arranged along the longitudinal direction of the catheter 100. Therefore, the flexibility of the catheter 100 in the first embodiment is higher than that of a catheter with a fully surface-treated surface. When the lifting distance is LX, the load LW1 of sample SA1 is smaller than the load LW3 of sample SA3. Sample SA1 is more easily bent radially than sample SA3 because the treated area S1 and the untreated area S2 are arranged along the longitudinal direction of the catheter 100. Therefore, the flexibility of the catheter 100 in the first embodiment is higher than that of a catheter without surface treatment. Improved flexibility means that the catheter 100 is more easily bent.

[0034] The lifting distance LD1 at kink position PK1 of sample SA1 is greater than the lifting distance LD2 at kink position PK2 of sample SA2. Sample SA1 is more prone to bending in the radial direction of catheter 100 than sample SA2 because the treated area S1 and the untreated area S2 are arranged along the longitudinal direction of catheter 100, resulting in a longer distance before catheter 100 kinks. Therefore, the kink resistance of catheter 100 in the first embodiment is higher than that of a catheter with a fully surface-treated surface. The lifting distance LD1 at kink position PK1 of sample SA1 is greater than the lifting distance LD3 at kink position PK3 of sample SA3. Sample SA1 is more prone to bending in the radial direction of catheter 100 than sample SA3 because the treated area S1 and the untreated area S2 are arranged along the longitudinal direction of catheter 100, resulting in a longer distance before catheter 100 kinks. Therefore, the kink resistance of catheter 100 in the first embodiment is higher than that of a catheter without surface treatment. Improved kink resistance means that the distance over which catheter 100 kinks increases.

[0035] Tensile tests were performed on the catheter samples SA1 to SA3 mentioned above. Figure 8 shows the results of the tensile tests. The tensile tests were performed as follows.

[0036] Focusing on the strain range of 0-100%, the curves of samples SA1-SA3 are almost identical. Therefore, in the strain range of 0-100%, the stress of the catheter 100 of the first embodiment, the stress of the fully surface-treated catheter, and the stress of the unsurface-treated catheter are approximately equivalent. Consequently, the catheter 100 of the first embodiment has sufficient tensile strength equivalent to that of the fully surface-treated catheter. The catheter 100 of the first embodiment has sufficient tensile strength equivalent to that of the unsurface-treated catheter. Therefore, when the catheter 100 of the first embodiment enters a bent area in the body, the possibility of the catheter 100 breaking is low.

[0037] (Effects of the first embodiment) As described above, the catheter 100 of this embodiment includes a tubular body 40 and a resin layer 50. The tubular body 40 is made of fluororesin. The tubular body 40 extends along its central axis Ax. The outer surface of the tubular body 40 has treated areas S1 where defluorination treatment has been applied and untreated areas S2 where defluorination treatment has not been applied. The resin layer 50 is located on the outer surface of the tubular body 40. The catheter 100 of this embodiment has high flexibility. The catheter 100 of this embodiment has high kink resistance. Therefore, the catheter 100 easily maintains its roundness. As a result, when the catheter 100 is inserted into a curved blood vessel, the accompanying device inserted inside the catheter 100 can penetrate well into the deep parts of the body. The catheter 100 of this embodiment can suppress the decrease in stretch resistance. Therefore, the catheter 100 of this embodiment can achieve improved flexibility, improved kink resistance, and suppression of the decrease in stretch resistance.

[0038] In the catheter 100 of this embodiment, the tubular body 40 has a cross-section that includes multiple untreated areas S2. The catheter 100 of this embodiment also has higher flexibility and kink resistance.

[0039] In the catheter 100 of this embodiment, the outer surface of the tubular body 40 has a first virtual line segment LS1 and a second virtual line segment LS2. The first virtual line segment LS1 and the second virtual line segment LS2 are located coaxially. The first virtual line segment LS1 and the second virtual line segment LS2 are parallel to the central axis Ax of the tubular body 40. The second virtual line segment LS2 is located proximal to the first virtual line segment LS1. The first virtual line segment LS1 and the second virtual line segment LS2 overlap the processed area S1. According to the catheter 100 of this embodiment, flexibility and kink resistance are improved over a wide range in the longitudinal direction.

[0040] In the catheter 100 of this embodiment, the length of the second virtual line segment LS2 is longer than the length of the first virtual line segment LS1. The tip of the catheter 100 of this embodiment has even greater flexibility.

[0041] In the catheter 100 of this embodiment, the tubular body 40 has a first portion P1, a second portion P2 located proximal to the first portion P1, and a third portion P3 located proximal to the second portion P2. The first portion P1 and the second portion P2 are adjacent to each other. The second portion P2 and the third portion P3 are adjacent to each other. The outer circumferential surfaces of the first portion P1 and the third portion P3 have one untreated area S2 and one treated area S1 adjacent to the untreated area S2 in the circumferential direction. The outer circumferential surface of the second portion P2 has one treated area S1. In the circumferential direction D1 of the tubular body 40, the position of the treated area S1 of the first portion P1 and the position of the treated area S1 of the third portion P3 are different from each other. The catheter 100 of this embodiment has high flexibility and kink resistance in any bending direction.

[0042] In the catheter 100 of this embodiment, the tubular body 40 further has a fourth portion P4 located proximal to the third portion P3. The third portion P3 and the fourth portion P4 are adjacent to each other. The outer surface of the fourth portion P4 has one treated area S1. The catheter 100 of this embodiment has even greater flexibility and greater kink resistance in any bending direction over an even wider range in the longitudinal direction.

[0043] In this embodiment, in at least one of the first portion P1 and the third portion P3, the length of the untreated portion S2 in the circumferential direction D1 is longer than the length of the treated portion S1 in the circumferential direction D1. That is, the length W2 of the untreated portion S2 of the first portion P1 is longer than the length W1 of the treated portion S1 of the first portion P1 in the circumferential direction D1. The length W4 of the untreated portion S2 of the third portion P3 is longer than the length W3 of the treated portion S1 of the third portion P3 in the circumferential direction D1. The catheter 100 of this embodiment also has higher flexibility and higher kink resistance.

[0044] In the catheter 100 of this embodiment, the first interface B1 between the first portion P1 and the second portion P2, and the second interface B2 between the second portion P2 and the third portion P3, are inclined with respect to a virtual plane VS perpendicular to the central axis Ax of the tubular body 40. The catheter 100 of this embodiment has even greater flexibility and kink resistance in any bending direction.

[0045] In the catheter 100 of this embodiment, the first interface B1 and the second interface B2 are parallel to each other. The catheter 100 of this embodiment has even greater flexibility and kink resistance in any bending direction.

[0046] In the catheter 100 of this embodiment, the reinforcing body 30 is located between the tubular body 40 and the resin layer 50. The catheter 100 of this embodiment has high torque and high kink resistance.

[0047] (Second Embodiment) Figure 9 is a side view of the tubular body 40a in the second embodiment. In the following, for components of the tubular body 40a in the second embodiment that are the same as those of the tubular body 40 in the first embodiment described above, the same reference numerals are used, and their descriptions will be omitted as appropriate.

[0048] The catheter 100a of the second embodiment differs from the catheter 100 of the first embodiment in that the shape of the untreated area S2 located on the outer surface of the tubular body 40a is helical. The untreated area S2 is continuous in a helical shape and has a length of more than one circumference. That is, one untreated area S2 is continuous from the tip to the base of the tubular body 40a. As a result, one treated area S1 is continuous from the tip to the base of the tubular body 40a. According to the catheter 100a of this embodiment, there is one untreated area S2 and one treated area S1. Therefore, the catheter 100a of this embodiment is easy to manufacture.

[0049] Since the distribution of treated areas S1 and untreated areas S2 on the outer surface of the tubular body 40a is as described above, a virtual straight line VL can be drawn on the outer surface of the tubular body 40a, parallel to the central axis Ax of the tubular body 40a, and having a first virtual line segment LS1 and a second virtual line segment LS2. The first virtual line segment LS1 and the second virtual line segment LS2 overlap the treated areas S1. The second virtual line segment LS2 is located on the proximal end side of the first virtual line segment LS1. According to the catheter 100a of this embodiment, flexibility and kink resistance are improved over a wide range in the longitudinal direction.

[0050] In this embodiment, the length of the second virtual line segment LS2 is longer than the length of the first virtual line segment LS1. The tip of the catheter 100a in this embodiment has even greater flexibility.

[0051] (Third embodiment) Figure 10 is a side view of the tubular body 40b in the third embodiment. In the following description, components of the tubular body 40b in the third embodiment that are the same as those of the tubular body 40 in the first embodiment described above will be denoted by the same reference numerals, and their explanation will be omitted.

[0052] The third embodiment differs from the first embodiment in that the shape of the untreated areas S2 located on the outer surface of the tubular body 40b is dot-shaped. That is, multiple untreated areas S2 are located on the outer surface of the tubular body 40b. One treated area S1 is continuous from the tip to the base of the tubular body 40b.

[0053] Since the distribution of treated areas S1 and untreated areas S2 on the outer surface of the tubular body 40b is as described above, a virtual straight line VL can be drawn on the outer surface of the tubular body 40b, parallel to the central axis Ax of the tubular body 40b, and having a first virtual line segment LS1 and a second virtual line segment LS2. The first virtual line segment LS1 and the second virtual line segment LS2 overlap the treated areas S1. The second virtual line segment LS2 is located on the proximal end side of the first virtual line segment LS1. According to the catheter 100b of this embodiment, flexibility and kink resistance are improved over a wide range in the longitudinal direction.

[0054] In this embodiment, the length of the second virtual line segment LS2 is longer than the length of the first virtual line segment LS1. The tip of the catheter 100b in this embodiment has even greater flexibility.

[0055] The tubular body 40b of this embodiment may have a cross-section that includes a plurality of untreated areas S2. The length W6 in the circumferential direction D1 of the plurality of untreated areas S2 is, for example, 0.1 times or more and 0.4 times or less the length of the outer circumference. The length W6 in the circumferential direction D1 of the plurality of untreated areas S2 may also be 0.15 times or more and 0.35 times or less the length of the outer circumference, or 0.2 times or more and 0.3 times or less the length of the outer circumference. The length W5 in the longitudinal direction of the untreated area S2 is, for example, 0.8 times or more and 1.2 times or less the length W6 in the circumferential direction D1 of the untreated area S2. The length W5 in the longitudinal direction of the untreated area S2 may also be 0.9 times or more and 1.1 times or less the length W6 in the circumferential direction D1 of the untreated area S2, or 0.85 times or more and 1.15 times or less the length W6 in the circumferential direction D1 of the untreated area S2. The catheter 100b of this embodiment has even greater flexibility in any bending direction.

[0056] (modified version) The technologies disclosed herein are not limited to the embodiments described above and can be modified in various forms without departing from their essence, for example, the following modifications are possible.

[0057] The configuration of the tubular body in the above embodiment is merely an example and can be modified in various ways. For example, the shape of the untreated area S2 located on the outer surface of the tubular body may be other shapes. For example, the shape of the untreated area S2 may be web-like. The web-like shape of the untreated area S2 is formed by a series of untreated areas S2 that are bent in a V-shape.

[0058] In the above embodiment, the untreated area S2 does not need to be formed along the entire length of the tubular body 40. For example, the untreated area S2 may be formed only at the tip and not at the base. In the above embodiment, the number of treated areas S1 and untreated areas S2 on the outer surface of the tubular body 40 may each be one.

[0059] In the above embodiment, the length of the second virtual line segment LS2 may be approximately the same as the length of the first virtual line segment LS1, or it may be shorter than the length of the first virtual line segment LS1.

[0060] In the first embodiment described above, the number of processed areas S1 and unprocessed areas S2 in the first part P1 and the third part P3 may be multiple. In the circumferential direction D1 of the tubular body 40 in the first embodiment described above, the position of the processed area S1 in the first part P1 and the position of the processed area S1 in the third part P3 may be the same. In both the first part P1 and the third part P3 in the first embodiment described above, the length of the unprocessed area S2 in the circumferential direction D1 may be shorter than the length of the processed area S1 in the circumferential direction D1. In the first embodiment described above, the tubular body 40 does not have a fourth part P4. The second part P2 and the fourth part P4 in the first embodiment described above may further have one unprocessed area S2. In the second part P2 and the fourth part P4 in the first embodiment described above, the number of processed areas S1 and unprocessed areas S2 may be multiple.

[0061] In the first embodiment described above, the first boundary surface B1 and the second boundary surface B2 may be parallel to a virtual plane VS perpendicular to the central axis Ax. In the first embodiment described above, the first boundary surface B1 and the second boundary surface B2 do not have to be parallel to each other.

[0062] In the above embodiment, the number of untreated areas S2 on the outer circumferential surface of the cross-section of the tubular bodies 40, 40a, and 40b may be one. In the above second embodiment, the number of untreated areas S2 on the outer circumferential surface of the tubular body 40a may be multiple. In the above second embodiment, the length of the untreated area S2 may be less than one full circumference.

[0063] In the above embodiment, the reinforcing body 30 may be a structure other than a braided body (for example, a coil). The catheters 100, 100a, and 100b do not have a reinforcing body 30. In the above embodiment, there may be other layers inside the tubular bodies 40, 40a, and 40b and outside the resin layer 50. The film thickness of the tubular bodies 40, 40a, and 40b, the resin layer 50, and the reinforcing body 30 in the above embodiment may vary over the entire length of the catheters 100, 100a, and 100b in the longitudinal direction.

[0064] The materials of each component in the catheters 100, 100a, and 100b of the above embodiment are merely examples and can be modified in various ways.

Claims

1. Catheters (100, 100a, 100b), A tubular body (40, 40a, 40b) formed of fluororesin, extending along a central axis (Ax), and having a treated area (S1) on the outer surface of the tubular body (40, 40a, 40b) that has been surface-treated to remove fluorine components, and an untreated area (S2) that has not been surface-treated, A resin layer (50) located on the outer circumference of the tubular body (40, 40a, 40b), A catheter (100, 100a, 100b) equipped with the following.

2. A catheter (100, 100a, 100b) according to claim 1, The outer surface of the tubular body (40, 40a, 40b) is A first imaginary line segment (LS1) is parallel to the central axis (Ax) of the tubular body (40, 40a, 40b) and overlaps with the processed portion (S1), A catheter (100, 100a, 100b) having a second virtual line segment (LS2) that is coaxial with the first virtual line segment (LS1), located proximal to the first virtual line segment (LS1), and overlapping the processed area (S1).

3. A catheter (100, 100a, 100b) according to claim 2, The length of the second virtual line segment (LS2) is longer than the length of the first virtual line segment (LS1) in the catheter (100, 100a, 100b).

4. A catheter (100) according to any one of claims 1 to 3, The tubular body (40) has a first portion (P1), a second portion (P2) located closer to the proximal end than the first portion (P1), and a third portion (P3) located closer to the proximal end than the second portion (P2). The outer circumferential surfaces of the first portion (P1) and the third portion (P3) have one untreated portion (S2) and one treated portion (S1) adjacent to the untreated portion (S2) in the circumferential direction (D1), The outer circumferential surface of the second portion (P2) has one of the treated portions (S1), A catheter (100) wherein, in the circumferential direction (D1) of the tubular body (40), the position of the processed portion (S1) of the first portion (P1) and the position of the processed portion (S1) of the third portion (P3) are different from each other.

5. A catheter (100) according to claim 4, A catheter (100) in which, in at least one of the first portion (P1) and the third portion (P3), the length of the untreated portion (S2) in the circumferential direction (D1) is longer than the length of the treated portion (S1) in the circumferential direction (D1).

6. A catheter (100) according to claim 5, A catheter (100) wherein the first interface (B1) between the first portion (P1) and the second portion (P2), and the second interface (B2) between the second portion (P2) and the third portion (P3) are inclined with respect to a virtual plane (VS) perpendicular to the central axis (Ax) of the tubular body (40, 40a, 40b).

7. A catheter (100) according to claim 6, A catheter (100) in which the first interface (B1) and the second interface (B2) are parallel to each other.

8. A catheter (100) according to claim 7, The tubular body (40) further has a fourth portion (P4) located on the proximal end side of the third portion (P3), The catheter (100) has one of the treated areas (S1) on the outer circumferential surface of the fourth portion (P4).

9. A catheter (100, 100a, 100b) according to any one of claims 1 to 3, The tubular bodies (40, 40a, 40b) have a cross-section including a plurality of the untreated areas (S2), and are catheters (100, 100a, 100b).

10. A catheter (100a) according to any one of claims 1 to 3, The catheter (100a) comprises the tubular body (40a) having the untreated portion (S2) on its outer surface, which is spirally continuous and has a length of at least one circumference.

11. A catheter (100, 100a, 100b) according to any one of claims 1 to 10, A catheter (100, 100a, 100b) further comprising a reinforcing body (30) located between the tubular bodies (40, 40a, 40b) and the resin layer (50).

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