JPH08215314A - Double tubes, apparatus for producing double tubes, balloon catheter using double tubes and production of balloon catheter - Google Patents

Abstract

PURPOSE: To provide double tubes with which a balloon catheter having high rigidity and low fluid resistance is easily produced by an extruder, etc., an apparatus for producing the double tubes, a balloon catheter formed by using the double tubes and a process for producing the balloon catheter. CONSTITUTION: These double tubes consist of an outer tube 1 which has a lumen penetrating the tube from the distal end to the proximal end and an inner tube 2 which is disposed within the lumen of this outer tube and has a lumen penetrating the tube from the distal end to the proximal end. The double tubes described above are provided with a band-shaped long-sized body as a juncture 3 for successively disposing the inside surface of the outer tube and the outside surface of the inner tube. This apparatus for producing the double tubes has a first extruding means for extruding a resin for forming the outer tube part, a second extruding means for extruding a resin for forming the inner tube part and a die for forming the respective resins extruded by the first extruding means and the second extruding means respectively to tubular shapes.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a double tube, a double tube manufacturing apparatus, a balloon catheter using the double tube, and a method for manufacturing a balloon catheter. More specifically, a balloon catheter having high rigidity can be easily manufactured. The present invention relates to a double tube suitable for use in, a double tube manufacturing apparatus suitable for manufacturing the same, a balloon catheter using the double tube, and a method for manufacturing a balloon catheter.

[0002]

2. Description of the Related Art A heart function assisting (so-called IABP) balloon catheter and a vasodilator (so-called PTCA) balloon catheter are composed of an outer tube and an inner tube provided in the lumen of the outer tube. It is a medical double tube. Further, in order to secure a space for folding and accommodating the balloon and facilitate insertion of the catheter into the living body, the outer tube is shorter than the inner tube at the distal end of the tube, and the balloon film is far from the outer tube. It is fixed at the proximal end and the distal end of the inner tube so that it can be wrapped around the inner tube and folded. In the medical double tube used for these balloon catheters, the inner tube moves freely within the lumen of the outer tube, so the inner tube is easily kinked, and the resistance of the fluid flowing through the lumen of the outer tube becomes high. Sex becomes low. In addition, in order to increase the cross-sectional area of the lumen, it is necessary to reduce the wall thickness of the tube, but in that case the rigidity of the tube as a whole is lowered or it is easy to kink, so that it is difficult to insert it into the body tube There was a problem of becoming. Therefore, as another medical double tube, a medical double tube has been proposed in which a part of the outer surface of the inner tube is tightly fixed to a part of the inner surface of the outer tube having one lumen. With this tube, the resistance of the fluid is reduced and the inner tube is prevented from kinking. However, since the inner surface of the outer tube and the outer surface of the inner tube are in close contact with each other, it is difficult to cut out the inner tube so as to make only the inner tube long and the outer tube short, which is not suitable for industrial mass production.

Single tubes or multi-layer tubes are mass-produced by an extruder or the like. The single tube is obtained by extruding the resin using a die having an annular hole. Also, the multilayer tube uses a die having one annular hole to extrude the resin forming the inner layer side from the axial direction of the die and at the same time deviate the resin forming the outer layer side by a predetermined angle from the axial direction of the die. It is obtained by extruding from a die, forming a two-layer structure in the die, and extruding from the die exit as it is. In the single-tube or double-layer tube extrusion molding, in order to secure a lumen region, gas is blown from the exit of the die of the extruder to prevent the lumen from being crushed and blocked. However, in the medical double tube, the lumen of the inner tube or the outer tube is easily crushed due to the pressure fluctuation of the blown air, so that the double tube is easily blocked. Therefore, the medical double tube could not be mass-produced by extrusion molding.

[0004]

DISCLOSURE OF THE INVENTION An object of the present invention is to provide a double tube capable of easily producing a balloon catheter having high rigidity and low fluid resistance by an extruder or the like.
A double tube manufacturing apparatus, a balloon catheter using the double tube, and a method for manufacturing a balloon catheter. As a result of earnest studies to achieve this object, the present inventors have found that the inner surface of the outer tube and the outer surface of the inner tube are continuously connected by a strip-shaped elongated body extending from the distal end to the proximal end. It was found that the above object can be achieved by using a heavy tube, and the present invention has been completed based on this finding.

[0005]

Thus, according to the present invention, (1) an outer tube having a lumen penetrating from a distal end to a proximal end and a lumen provided in the outer tube, the proximal end being provided from the distal end A medical double tube having an inner tube having a lumen penetrating the end, wherein a part of the inner surface of the outer tube and a part of the outer surface of the inner tube are connected via a connecting portion extending from the distal end to the proximal end. A double tube is provided, characterized in that the connecting portion has a shape capable of separating the inner surface of the outer tube and the outer surface of the inner tube at a desired distance. (2) The double tube of (1) above, wherein the connecting portion is a long body extending from the distal end to the proximal end, and (3) the long body is arranged in the longitudinal direction thereof. The double tube of (1) above, which has a continuous cutout portion, and (4) the cutout portion is located in the inner surface of the outer tube or in the portion close to the outer surface of the inner tube. A double tube for a balloon catheter having the above-mentioned double tube of (3) and (5) any one of the characteristics of (1) to (4) is provided.

According to the present invention, (6) first extruding means for extruding the resin forming the outer tube portion of the double tube, second extruding means for extruding the resin forming the inner tube portion of the double tube, and first An extrusion molding apparatus having a die for forming each resin extruded by the extruding means and the second extruding means into a tubular shape, wherein the die is a first extruding means through which the resin extruded by the first extruding means passes from the rear side to the front side of the die. One annular hole, the resin extruded by the second extruding means has a second annular hole passing from the die back to the front, the second annular hole is provided inside the first annular hole,
A slit is formed in the inner hole wall of the first annular hole or the outer hole wall of the second annular hole from the front outlet of the first annular hole or the second annular hole toward the rear, and the inner tube portion is formed by the slit. The first extruding means is such that the resin extruded from the first extruding means passes through the first annular hole of the die from the rear to the front. The second extruding means is connected to the die so that the resin extruded from the second extruding means can pass through the second annular hole of the die from the rear to the front. A double tube manufacturing apparatus is provided, and as a preferred embodiment,

(7) A slit is formed in the inner hole wall of the first annular hole or the outer hole wall of the second annular hole within a range of 10 mm rearward from the front exit of the first annular hole or the second annular hole. (6) The double tube manufacturing apparatus according to (6), and (8) the slit is formed so as to be located above the second annular hole. (6)
Alternatively, the double tube manufacturing apparatus of (7) is provided.

According to the present invention, the length of the outer tube is shorter than the length of the inner tube, and the inner tube distal end extends more distally than the outer tube distal end (1), A balloon catheter having a double tube of (2), (3), (4) or (5) and a balloon, wherein the balloon is formed of a cylindrical film, one end of which is the inner tube distal end. Further, there is provided a balloon catheter characterized in that the other end is fixed to the outer tube distal end.

According to the present invention, the above (1),
(2), (3), (4) or (5) outer tube distal end of the outer tube at a position separated from the outer tube distal end by a desired length, A step of separating the outer tube from the distal end of the outer tube to the rounded portion, a step of removing from the distal end of the outer tube to the rounded portion, and one end of the cylindrical film having the outer tube rounded portion And a step of fixing the other end to the distal end of the inner tube.

The double tube of the present invention is a double tube including an outer tube and an inner tube,
The inner surface of the outer tube and the outer surface of the inner tube are connected to each other via a connecting portion extending from the distal end to the proximal end. The connecting portion has a shape capable of separating the inner surface of the outer tube and the outer surface of the inner tube by a desired distance. The connection part is usually an elongated body extending from the distal end to the proximal end. The elongated body is not limited by its cross section, and may be a polygon such as a rectangle, a square, a rhombus, a trapezoid, a triangle, or a pentagon; a circle such as a perfect circle or an ellipse. The elongated body has a shape extending in the longitudinal direction of the tube, and has a rod-like or strip-like shape.

The elongated body is usually made of the same material as the outer tube or the inner tube,
In order to facilitate the separation from the outer tube or the inner tube, it is preferable to use a material different from the material forming the outer tube or the inner tube. The connecting portion has a height such that the distance between the outer surface of the inner tube and the inner surface of the outer tube is usually 0.05 to 3 mm, preferably 0.1 to 2 mm. The thickness of the connection is
It is preferable that it is as small as possible in order to facilitate separation from the outer tube or inner tube.
0.03 to 0.8 mm, preferably 0.05 to 0.6 m
m.

In order to facilitate the separation from the outer tube or the inner tube, it is preferable to use an elongated body having a notch 6 continuous along the major axis direction at the connecting portion. The size of the cutout portion is not particularly limited.
The notch is provided between the outer surface of the inner tube and the inner surface of the outer tube. It should be installed near the outer surface of the inner tube or the inner surface of the outer tube to facilitate separation of the outer tube (Fig. 3).
(A), (B), (D) or (E)) are preferred.

[0013]

In the double tube of the present invention, the space surrounded by the outer tube and the inner tube is used for passing the liquid or gas for inflating the balloon of the balloon catheter. In the double tube of the present invention, the outer tube and the inner tube are connected to each other through the connecting portion, so that the inner tube does not meander in the outer tube even when the double tube is twisted or wound. Therefore, the passage resistance of the liquid or gas for inflating the balloon becomes small. Further, in the double tube of the present invention, the outer tube and the inner tube are connected in series via the connecting portion, so that the connecting portion functions as a skeleton member to enhance the rigidity of the entire tube.

The balloon catheter is usually a double tube in which the inner tube is longer than the outer tube and the inner tube extends distally from the distal end of the outer tube. Since the double tube of the present invention can easily disengage the outer tube and the inner tube from each other by cutting off the connection part, the step of cutting the outer tube, the outer part from the distal end to the outer tube cutting part is cut. The step of separating the tube from the connection part and the step of separating the connection part from the distal end to the outer tube slice and the inner tube, by removing the outer tube, the inner tube is better than the outer tube without damaging the inner tube. It is possible to easily obtain a double tube that is also long and extends in the distal direction from the outer tube distal end (circular cut portion).

Further, in the double tube of the present invention,
A connecting part having a continuous cutout along its major axis direction can be easily separated at the cutout, so that the outer tube can be cut off more easily.

In the double tube manufacturing apparatus of the present invention, the resin extruded by the first extruding means passes through the first annular hole 13 to form the outer tube portion, and the resin extruded by the second extruding means is the second annular shape. Since the inner tube portion is formed by passing through the hole 14, it is possible to effectively prevent the lumen of the inner tube or the outer tube from being crushed or deformed due to the pressure fluctuation of the blown air. Further, since slits are formed rearward from the front exits of the first annular hole 13 or the second annular hole 14, the front exits of the first annular hole 13 and the second annular hole 14 pass through both annular holes. It is possible to mass-produce a double tube in which a portion of the outer surface of the inner tube and a portion of the inner surface of the outer tube 1 are connected to each other at the connection portion by contacting the resin.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A double tube according to an embodiment of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a partially broken view of a double tube according to an embodiment of the present invention, FIG. 2 is a sectional view taken along the line II ′ of the tube shown in FIG. 1, and FIG. 3 is a mode example of a connecting portion of the double tube of the present invention. FIG. 4 is a view showing a cross section of an embodiment of the double tube manufacturing apparatus of the present invention, and FIGS. 5, 6 and 7 are views showing the shape of a die used in the double tube manufacturing apparatus of the present invention. FIG. 8 is a schematic view showing a process of manufacturing a balloon catheter using the tube shown in FIG.

As shown in FIG. 1, a double tube according to an embodiment of the present invention is an outer tube 1 and an outer tube 1 having a lumen extending from a distal end to a proximal end.
Is a double tube consisting of an inner tube 2 having a lumen that is provided in the lumen and that extends from the distal end to the proximal end. The inner diameter of the outer tube 1 is usually 0.
4 to 6 mm, preferably 0.5 to 4 mm, the outer tube 1 usually has a wall thickness of 0.03 to 0.8 mm,
It is preferably 0.05 to 0.6 mm.

Since the outer tube 1 is a portion which is inserted into a living body tube and comes into contact with living tissue, the material used for the outer tube 1 is usually a biocompatible material. Examples of biocompatible materials include polyamide resins, polyimide resins, fluororesins, polyvinyl chloride resins, polypropylene resins, polyethylene resins, polyurethane resins and the like. The biocompatible material may be blended with a contrast agent, an antibacterial agent, or the like.

The inner diameter of the inner tube 2 is usually 0.
2-3 mm, preferably 0.3-2 mm, the inner tube 2 usually has a thickness of 0.03-0.8 mm,
It is preferably 0.05 to 0.6 mm. Although the inner tube 2 does not come into direct contact with the living tissue, it is made of a biocompatible material like the outer tube 1 because biological fluid enters the lumen of the inner tube 2.

The connecting portion 3 connecting the inner surface of the outer tube 1 and the outer surface of the inner tube 2 is a long body. The elongated body is not limited by its cross section, and may be a polygon such as a rectangle, a square, a rhombus, a trapezoid, a triangle, or a pentagon; a circle such as a perfect circle or an ellipse (FIG. 3). A triangular shape, a pentagonal shape, and a rhombus shape are preferable in order to facilitate separation of the inner tube 2 and the outer tube 1 when processing the double tube into a balloon catheter. For the elongated body, the same material as the material forming the outer tube 1 or the inner tube 2 is usually used. In order to facilitate the separation from the outer tube 1 or the inner tube 2, it is preferable to use a material different from the material forming the outer tube 1 or the inner tube 2. The distance between the outer surface of the inner tube 2 and the inner surface of the outer tube 1 of the connecting portion 3 is usually 0.05 to 3 mm, preferably 0.1 to 2 mm.
It has a height of mm. The thickness of the connecting portion 3 is preferably as small as possible in order to facilitate the separation from the outer tube 1 or the inner tube 2, and is usually 0.
It is 03 to 0.8 mm, preferably 0.05 to 0.6 mm.

In order to facilitate the separation from the outer tube 1 or the inner tube 2, it is preferable to use, as the connecting portion 3, a long body having a notch portion 6 continuous along the major axis direction. The size of the cutout portion is not particularly limited. The notch is usually provided at a position between the outer surface of the inner tube 2 and the inner surface of the outer tube 1. However, in order to facilitate separation of the outer tube 1, the notch is provided at a position close to the outer surface of the inner tube 2 or the inner surface of the outer tube 1. It is preferable to provide.

The double tube of the present invention is usually manufactured by an extrusion method. Specifically, charge the material into one extruder and extrude the material from the die using this extruder, or charge the material for the outer tube into one extruder and insert the material into the other extruder. For example, the materials for the tube are charged, and the materials are simultaneously extruded from the die by using the two extruders. When the latter method of molding using two extruders is adopted, the outer tube material and the inner tube material are pushed into the connecting portion 3 to form an interface, which facilitates separation of the outer tube 1. The shape of the mouthpiece may be any shape as long as the inner tube 2, the outer tube 1 and the connecting portion 3 are extruded at the same time. The mouthpiece may be provided with an air outlet for securing the lumen of the inner tube 2 and the outer tube 1.

The manufacturing apparatus suitable for industrially mass-producing the double tube of the present invention is the first extrusion means 1 for extruding the resin forming the outer tube portion of the double tube.
1. Extrusion having a second extruding means 12 for extruding a resin forming the inner tube portion of the double tube, a first extruding means 11, and a die for forming each resin extruded by the second extruding means 12 into a tubular shape. It is a molding device.

First extrusion means 11 and second extrusion means 12
Is for press-fitting resin from the rear of the die and discharging resin from the outlet in front of the die. The first extruding means 11 and the second extruding means 12 can be connected so that the resin extruded from each of them can pass through the annular hole in the die.

As the first extruding means 11 and the second extruding means 12, an extruder having an extruding mechanism such as a screw, a gear (gear), a planetary screw and a rotating disk can be usually mentioned.
Specific examples of the extruder include a single-screw extruder, a twin-screw extruder, a vent-type extruder, a kneading extruder, a two-stage extruder, a multi-screw extruder,
An oblique multi-screw extruder, a planetary screw extruder, a gear type extruder, a ram type extruder, a rotating disk type extruder and the like can be mentioned.

The die is a mold for molding the resin extruded by the first extruding means 11 and the second extruding means 12 into a desired shape. 5 (1-A) and (2-A),
6 (1-A) and (2-A) and FIG. 7 (1-A) are cross-sectional views showing aspects of a die used in the double tube manufacturing apparatus of the present invention, FIGS. 5 (1-B) and (2). -B), FIG. 6 (1
-B) and (2-B) and FIG. 7 (1-B) are respectively FIG. 5 (1-A) and (2-A), FIG. 6 (1-A) and (2-A) and FIG. 7 ( 1-A) is a front view of the die shown in FIG.

In the manufacturing apparatus of the present invention, the die has a first annular hole 13 through which the resin extruded by the first extruding means 11 passes and a second annular hole 14 through which the resin extruded by the second extruding means 12 passes. The second annular hole 14 is provided inside the first annular hole 13 (inside the ring). The first annular hole 13 and the second annular hole 14 of the die are usually not substantially in communication. First annular hole 13 and second annular hole 14
Since the resin is not substantially communicated with, when the resin is extruded by the first extruding means 11, the resin can be exhaled from the first annular hole 13 to form the outer tube 1 portion, and the second extruding means 1
When the resin is extruded by 2, the resin is extruded from the second annular hole 14 and the inner tube 2 portion can be formed. here,
The term “not substantially communicating” means that only a small portion provided with a slit described later can communicate.

In the die of the manufacturing apparatus of the present invention, a connecting portion for connecting a part of the inner surface of the outer tube 1 and a part of the outer surface of the inner tube 2 to the first annular hole 13 or the second annular hole 14 of the die. Slits 15 for forming 3 are connected. The length of the slit is usually about 10 mm or less, preferably 5 mm or less, from the outlet in front of the die toward the rear.
Alternatively, it is preferable to prevent the outer tube 1 from being crushed or blocked. The slit 15 is usually the first annular hole 1
3 or the second annular hole 14 communicates. Slit 15
Is provided in either the first annular hole 13 or the second annular hole 14 (FIG. 5 (2-A) or FIG. 6 (1-
A)), so that the bottom of the slit 15 is close to the second annular hole 14 or the first annular hole 13, usually 1 mm or less,
If the slits 15 are provided in both the first annular hole 13 and the second annular hole 14 (FIG. 7 (1-A)), the slits 15 are preferably formed at a distance of 0.5 mm or less. 1mm or less, so that the bottoms of
It is preferable to provide the slit 15 so that the distance is 0.5 mm or less so that a part of the inner surface of the outer tube 1 and a part of the outer surface of the inner tube 2 are connected to each other. In addition, the slit 15 is provided in both the first annular hole 13 and the second annular hole 14 so that the first annular hole 13 and the second annular hole 14 communicate with each other, the connecting portion, the inner tube, and the inner tube. This is preferable because it is surely connected to the outer tube.

The size of the first annular hole 13 or the second annular hole 14 can be appropriately selected according to the outer and inner diameters of the outer tube 1 and the inner tube 2 of the double tube. The shape of the slit 15 is such that it can communicate with the first annular hole 13 or the second annular hole 14, and can form the connecting portion 3 that connects a part of the inner surface of the outer tube 1 and a part of the outer surface of the inner tube 2. It is a thing. For example, when the die is observed from the front in the axial direction, it may be a quadrangle as shown in FIG. 5 (1-B), or may be as shown in FIG. 5 (2-B) or FIG.
It may be a triangle as shown in FIG. 6-B), a pentagon or a diamond as shown in FIG. In order to facilitate separation of the inner tube 2 and the outer tube 1 when processing the double tube into a balloon catheter, a triangle, a pentagon, and a rhombus are used to obtain a double tube having a cross section as shown in FIG. preferable. The width and depth of the slit 15 are
It may be designed according to the size of the connecting portion 3 connecting the outer tube 1 and the inner tube 2 in series.

The die has an air outlet (not shown) to secure the lumen of the tube inside the second annular hole 14 (inside the ring) and outside the second annular hole 14 (outside the ring). ) Can be provided inside the first annular hole 13 (inside the ring).

In the manufacturing apparatus of the present invention, the die is usually attached so that the first annular hole 13 and the second annular hole 14 of the die are substantially horizontal. In the manufacturing apparatus of the present invention, in order to improve the dimensional stability of the lumens of the inner tube 2 and the outer tube 1 of the double tube, the die is first extruded so that the slit 15 is above the second annular hole 14. Those attached to the means 11 and the second extrusion means 12 are preferable.

As shown in FIG. 8, the method for manufacturing a balloon catheter using the double tube of the present invention is as follows. The outer tube is separated from the distal end of the outer tube 1 by a desired length as shown in FIG. 1, a step of separating the connecting portion 3 from the distal end to the looped portion and a step of separating the outer tube 1 from the distal end to the looped portion, the outer tube 1 from the distal end A step of removing up to a part and a step of covering from the circular cut portion to the inner tube 2 distal end portion with a cylindrical film, and fixing one end of the film to the outer tube 1 circular cut portion and the other end to the inner tube 2 distal end. Is to have.

In the step of slicing the outer tube 1, the slicing position differs depending on the intended balloon catheter, but usually 10 to 500 mm from the distal end,
It is preferably 50 to 400 mm. The means for slicing is not particularly limited and, for example, means for cutting the wall of the outer tube 1 with a pipe cutter, a knife or the like can be adopted.

In the step of separating the distal end of the connecting portion 3 from the cut portion and the distal end of the outer tube 1 to the cut portion, the separating means is
There is no particular limitation, and for example, there are means for tearing and separating, means for cutting and separating with a knife or the like. Through these steps, it is possible to remove from the distal end of the outer tube 1 to the above-mentioned sliced portion. In addition, in order to smooth the outer surface of the inner tube 2 which extends in the distal direction from the outer tube 1 distal end and projects, the distance from the distal end of the connecting portion 3 to the above-mentioned looped portion and the inner tube 2 is increased. You may add the process of isolate | separating from the front end to the said loop-cut part, and may remove from the inner tube 2 from the distal end of the connection part 3 to the said wheel-cut part.

After removing from the distal end of the outer tube 1 to the circular cut portion, a cylindrical film is used to cut the outer tube 1 circular cut portion (hereinafter, also referred to as outer tube 1 distal end) to the inner tube 2 distal end. Then, one end of the film is fixed to the outer tube 1 distal end and the other end is fixed to the inner tube 2 distal end. The cylindrical film is for forming a balloon. The thickness of the film is usually 80 to 150 μm, and the area of the film is usually 10 when the film is fixed and a balloon is formed and then expanded.
~ 80 cm3, the outer diameter of the balloon is usually 10
20 mm, the length of the balloon in the long axis direction is usually
The range is such that it becomes 10 to 500 mm. As the film, a material having excellent bending fatigue resistance and antithrombogenicity is used. Examples thereof include polyurethane and natural rubber. The film is fixed to the outer tube 1 distal end and the inner tube 2 distal end by means such as heat fusion or adhesion.

[0037]

In the double tube of the present invention, the outer tube and the inner tube are continuously connected through the connecting portion, so that even if the double tube is twisted or wound, the inner tube is kept inside the outer tube. Do not meander. Therefore, the passage resistance of the liquid or gas for inflating the balloon becomes small. Since the outer tube and the inner tube are connected to each other via the connecting portion, the connecting portion functions as a skeleton member and enhances the rigidity of the entire tube.

In the double tube of the present invention, the outer tube and the inner tube can be easily disconnected from each other by cutting off the connecting portion for connecting the outer tube and the inner tube. The step of separating the outer tube from the distal end to the outer tube loop cut portion and the connecting portion and the step of separating the connection portion from the distal end to the outer tube loop cut portion and the inner tube are performed in any order, By removing only the outer tube, the inner tube longer than the outer tube and exposed from the outer tube distal end can be easily obtained without damaging the inner tube.

Further, in the double tube of the present invention,
If the connecting portion has a cutout portion that is continuous along the major axis direction, the cutout portion can be easily separated, so that the outer tube can be cut off more easily.

The double tube of the present invention is suitable for medical use, particularly for balloon catheters.

[Brief description of drawings]

FIG. 1 is a partially broken view of a double tube according to an embodiment of the present invention.

2 is a cross-sectional view taken along the line I-I 'of the double tube shown in FIG.

FIG. 3 is a diagram showing an example of a cross-sectional shape of a connecting portion of the double tube of the present invention.

FIG. 4 is a diagram showing a cross section of an embodiment of the double tube manufacturing apparatus of the present invention.

FIG. 5 is a view showing an aspect of a die used in the double tube manufacturing apparatus of the present invention.

FIG. 6 is a view showing another embodiment of a die used in the double tube manufacturing apparatus of the present invention.

FIG. 7 is a view showing another embodiment of a die used in the double tube manufacturing apparatus of the present invention.

FIG. 8 is a schematic view showing a process of manufacturing a balloon catheter using the double tube shown in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Outer tube 2 ... Inner tube 3 ... Connection part 4 ... Slice (outer tube distal end) 5 ... Balloon 6 ... Notch part 10 ... Die 11. ..First extrusion means 12 ... Second extrusion means 13 ... First annular hole 14 ... Second annular hole 15 ... Slit

Claims (4)

[Claims] 1. A medical double having an outer tube having a lumen penetrating from a distal end to a proximal end and an inner tube provided in the lumen of the outer tube and having a lumen penetrating from the distal end to the proximal end. A tube, wherein a part of the inner surface of the outer tube and a part of the outer surface of the inner tube are connected through a connecting part that connects from the distal end to the proximal end, and the connecting part is the inner surface of the outer tube. A double tube having a shape capable of separating the outer surface of the inner tube from a desired distance. 2. A first extruding means for extruding a resin forming an outer tube portion of the double tube, a second extruding means, a first extruding means and a second extruding means for extruding a resin forming an inner tube portion of the double tube. An extrusion molding apparatus having a die for forming each resin extruded in a tubular shape, wherein the die is a first annular hole through which the resin extruded by the first extruding means passes from the rear side to the front side of the die, The resin extruded by the extrusion means has a second annular hole through which the die passes from the rear side to the front side, and the second annular hole is provided inside the first annular hole, and the first annular hole or the front exit of the second annular hole. From the rear to the rear, a slit is formed in the inner hole wall of the first annular hole or the outer hole wall of the second annular hole, and the resin and the outerch that form the inner tube portion by the slit. It is designed to form a connecting portion that connects with the resin forming the tube portion, and the first extruding means allows the resin extruded from the first extruding means to pass from the rear to the front through the first annular hole of the die. A double tube characterized in that the second extruding means is connected to the die so that the resin extruded from the second extruding means can pass through the second annular hole of the die from the rear to the front. Manufacturing equipment. 3. The double tube according to claim 1, wherein the length of the outer tube is shorter than the length of the inner tube, and the inner tube distal end extends in the distal direction more than the outer tube distal end. A balloon catheter having a balloon, wherein the balloon is formed of a cylindrical film, wherein one end of the film is fixed to the inner tube distal end and the other end is fixed to the outer tube distal end. Balloon catheter. 4. The step of slicing the outer tube at a position separated from the distal end of the outer tube of the double tube according to claim 1 by a desired length, the step from the distal end of the connecting portion to the sloping portion and the outer. A step of separating from the distal end of the tube to the rounded portion, a step of removing from the distal end of the outer tube to the rounded portion and one end of the cylindrical film to the outer tube rounded portion and the other end to the inner tube And a step of fixing the balloon catheter to the distal end.