JPH0910314A - Catheter with expander and its manufacture - Google Patents

Abstract

PURPOSE: To provide a catheter with expander which has few steps for construction, easy to be constructed, does not damage blood vessel nor generate fold. CONSTITUTION: An outer tube 1 is composed of a flexible head part 11, an intermediate part 12 whose inner/outer diameter is larger than the head part 11, and a thick base end part 13 which has further larger diameter than the intermediate part 12, and the head part 11 is provided with an expander 10 which can be contracted and folded, and this catheter is molded smoothly and seamlessly in one body from the head part including the expander 10 to the thick base end part 13, in a catheter with expander in which the outer tube 1 and the inner tube 2 are arranged coaxially. Therefore, this catheter is free from troubles such as incomplete liquid tightness and damage in blood vessel or the like due to junction steps or the like because it does not have junction, and is easy to be manufactured with fewer steps.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a catheter with an expander for expanding a stenosis occurring in a blood vessel to increase the flow rate of blood on the peripheral side of the stenosis and a method for producing the catheter.

[0002]

2. Description of the Related Art Conventionally, a catheter with an expandable body of this type is
It is roughly classified into a double-tube catheter in which a catheter tube body is coaxially arranged and an outer tube and an inner tube are formed, and a so-called double-lumen catheter having another lumen in the wall of the tube body. As a typical example of the former catheter, as shown in Japanese Patent Application Laid-Open No. 64-2659, for example, an expander, an outer tube and an inner tube are molded separately, and then the distal end of the expander is formed. The tip of the inner tube,
It is manufactured by joining the base end portion of the expansion body and the tip end portion of the outer tube by heat welding or the like. In addition, so that it can be applied to both the former and the latter, for example, JP-A-63-183.
According to the manufacturing method of the expansion body as described in the specification No. 070 and the Japanese Patent Laid-Open No. 192456/1988, only the expansion body portion is formed in advance, and then the catheter tube body is bonded by heat welding or an adhesive. It is manufactured by joining them together.

An advantage of the type completed by forming the expansion body and the catheter tube body separately and then joining them is that the material forming the expansion body is not limited to the material forming the catheter tube body. It is possible to improve the rigidity of the catheter tube body. An example of improving the rigidity of the latter is shown in Japanese Patent Application Laid-Open No. 59-186563, in which the shape and flexibility of the distal end portion and the proximal end portion of the tube are controlled by devising the tube extrusion molding method. In addition, there are those disclosed in Japanese Patent Application Laid-Open No. 60-31765, in which a rigidity imparting body such as a wire blade is provided on the tube to improve rigidity.

As described above, various studies have been made so far in order to impart rigidity to the catheter tube main body and improve the possibility of pushing the catheter to the distal end inside the blood vessel, so-called pushability. Besides, after forming each of the outer tube and the inner tube as different members of a relatively flexible distal end portion and a relatively rigid proximal end portion, as shown in, for example, JP-A-3-207376. Some are manufactured by joining to form a catheter tube body.

In addition to the above matters, the most stress such as bending and pulling is exerted in the operation of introducing and withdrawing the catheter into the body, or in the operation of connecting the drug injector and the pressure fluid introducer to the manifold. Various contrivances have heretofore been made to prevent bending around the connecting portion between the catheter tube and the manifold, that is, to reinforce the proximal end portions of the outer tube and the inner tube.
As shown in the specification of JP-A-4-2659, bending preventing tubes are coaxially arranged on the outer peripheral surfaces of the base ends of the outer tube and the inner tube, and the outer tube and the inner tube are heat-welded or bonded to each other. Some of them are manufactured by joining them by adhering them with an agent.

[0006]

However, first of all, regarding the catheter with an expandable body, the expandable body is formed separately from the catheter tube main body, including an example in which rigidity is given to the catheter tube main body to improve pushability. Requires a step of forming an expansion body in advance by any of the above methods, and further joining the catheter tube body and the expansion body by welding or bonding the distal end portion and the proximal end portion of the expansion body, respectively. ,
There are problems such as complicated work for that purpose and an increase in the number of steps for assembling the entire catheter with a dilator. In the case where the catheter tube main body is provided with a rigidity imparting body such as a wire blade to improve the rigidity, in addition to the above, more complicated work is added.

Further, as in the above-mentioned step, since the dissimilar body and the catheter tube body which are essentially different from each other are joined by the secondary processing means, it is necessary to always doubt the completeness of the liquid tightness of the joined portion. In addition, the possibility that steps, scratches or fluffing may occur on the outer surface of the joint cannot be abandoned, and in such a case it may damage the blood vessel of the patient and cause a serious situation. . In addition, each of the outer tube and the inner tube described above is manufactured by forming a catheter tube body by forming a relatively flexible distal end portion and a relatively rigid proximal end portion as different members and then joining them. The catheter with the expandable body has a problem for the same reason as in the case of the expandable body.

Furthermore, regarding the catheter with an expandable body in which the bending near the connecting portion between the catheter tube and the manifold is prevented, that is, the bending of the proximal end portions of the outer tube and the inner tube is prevented, the complicated work and expansion thereof are required. There is a problem that the number of steps for assembling the whole body catheter is increased. And at the same time,
At the boundary portion of the bending preventing tube joined to the base end portion of each of the outer tube and the inner tube and the tip side of each of the outer tube and the inner tube, stress is concentrated at the boundary portion due to the sudden change in outer shape, There is also a problem in that a bend occurs unintentionally there.

Therefore, an object of the present invention is to reduce the number of steps for assembling the entire catheter with an expandable body and facilitate it, and to prevent the inside of a blood vessel from being damaged, and also to prevent the occurrence of bending. To provide. A further object of the present invention is to provide a method for manufacturing the above catheter with an expandable body.

[0010]

[Means for Solving the Problems] In order to achieve the above object, the inventors of the present invention have made extensive studies and found that in a catheter with an expandable body, the expandable body, the distal end portion, the intermediate portion, and the proximal end portion of the catheter tube main body are The present invention has been achieved by forming all of them smoothly and integrally to make them seamless. That is, a first aspect of the present invention is a catheter with an expandable body in which an outer tube and an inner tube are coaxially arranged, wherein the outer tube has a flexible tip portion,
An intermediate portion having an inner and outer diameter larger than the tip portion, and a thick-walled base end portion having an inner and outer diameter larger than the intermediate portion, and the tip portion has an expandable body capable of contracting or folding. The catheter with an expandable body is characterized in that it is integrally and smoothly molded from the distal end portion including the expandable body to the base end portion without a seam.

In a second aspect of the present invention, the outer pipe and the inner pipe are coaxially arranged, and the outer pipe has a flexible tip portion, an intermediate portion having an inner and outer diameter larger than the tip portion, and the intermediate portion. It is composed of a thicker base end portion with an inner and outer diameter that is even larger, and has a expandable body capable of contracting or folding at the distal end portion, and there is no seam from the distal end portion including the expandable body to the base end portion. A method for manufacturing a catheter with a dilator that is smoothly integrally molded,
A step of forming a tube body forming the outer tube; a step of blow molding a flexible tip portion of the outer tube to form the expansion body; a step of forming the inner tube; and a step of forming the outer tube in the outer tube. It is intended to provide a method for manufacturing a catheter with an expandable body, which comprises a step of inserting an inner tube and a step of fixing a tip portion of the outer tube and a tip portion of the inner tube.

As an example of improving the rigidity of the catheter tube main body without providing the rigidity imparting body or without joining after forming the distal end portion and the proximal end portion as different members, the above-mentioned special features are Kaisho 59-186563
And those disclosed in Japanese Patent Laid-Open No. 60-31765.
There is one shown in the specification. These are for simplifying the process of processing the catheter tube body itself to give rigidity, but the outer diameter and / or inner diameter of the tip portion and the intermediate portion are the same, as shown in the present invention, It was not applicable to a catheter with an expandable body in which the expandable body is integrally formed at the tip portion.

Therefore, the inventors of the present invention do not have a step of processing the catheter tube main body itself to give rigidity, maintain a certain degree of rigidity, further integrally mold the expansion body, and further bend the base end portion. The present invention has been achieved as a result of extensive studies on the structure and design of a catheter tube and the manufacturing method of the catheter tube that satisfy the prevention at the same time.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A catheter with an expandable body of the present invention will be described below with reference to the drawings showing an embodiment. 1 is a drawing showing the entire catheter with an expandable body of the present invention, and FIG.
4 and 5 are respectively AA, BB, CC of FIG.
It is drawing which shows each cross section in DD. The catheter with an expandable body according to the present embodiment has a manifold having an outer tube 1, an inner tube 2 arranged coaxially with the lumen of the outer tube 1, and an opening communicating with the lumen of each of the outer tube 1 and the inner tube 2. It consists of 3.

The outer tube 1 has a flexible tip 11 and a tip 11
It is composed of a middle portion 12 having a larger inner and outer diameter and a thicker base end portion 13 having an inner and outer diameter larger than the middle portion 12, and a distal end portion 11 has an expandable body 10 capable of contracting or folding, The front end portion 11 including the body 10 to the base end portion 13 are seamlessly and integrally molded.

The inner tube 2 is composed of a flexible tip portion 21, an intermediate portion 22 having an inner and outer diameter larger than the tip portion 21, and a base end portion 23 having an inner and outer diameter larger than the intermediate portion 22 and a thick wall. The front end portion 21 to the base end portion 23 are seamlessly and integrally molded.

In the lumen of the expansion body 10, an X-ray opaque marker ring 30 is coaxially arranged and fixed to the outer peripheral surface of the distal end portion 21 of the inner tube corresponding to the central portion of the expansion body 10. As the ring 30, for example, gold, platinum,
A material formed of tungsten or an alloy material containing them can be preferably used. The outer tube 1 and the inner tube 2 are liquid-tightly fixed only at the tip 40 of the catheter with an expandable body.

The details of each component of the catheter with an expandable body of the present invention will be described below with reference to the drawings. Outer tube 1
The inner tube 2 is preferably made of a flexible material, for example, polyolefin such as polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, polyamide, polyvinyl chloride, polyurethane, etc. The thermoplastic resin, polyimide, polyamide elastomer, silicone rubber, latex rubber, etc. can be used. The thermoplastic resin is preferable, and the polyolefin resin is more preferable. It can be formed by extruding these materials and cutting them into a predetermined size. It may also be formed by injection molding or dipping into a male mold.

The total length of the outer tube 1 is 300 to 2000 mm, preferably 500 to 1500 mm, and the tip portion 11 of the outer tube 1 has a length of 50 to 350 mm, preferably 100 to 100 mm.
300 mm, the outer diameter is 0.50 to 2.00 mm, preferably 0.70 to 1.50, and the inner diameter is 0.30 to 1.
It is 80 mm, preferably 0.45 to 1.25 mm.

The intermediate portion 12 of the outer tube 1 has a length of 150-18.
00 mm, preferably 500 to 1500 mm, and the outer diameter is 0.60 to 2.10 mm, preferably 0.80 to 1.60.
mm, and the inner diameter is 0.40 to 1.90 mm, preferably 0.60 to 1.40 mm.

The base portion 13 of the outer tube 1 has a length of 20 to 150.
mm, preferably 25-120 mm, outer diameter 0.80
~ 6.00 mm, preferably 2.00-4.00 mm, inner diameter 0.60-2.80 mm, preferably 0.80
~ 1.60 mm.

The extension body 10 formed integrally with the tip portion 11 of the outer tube 1 has a length of 5 to 45 mm, preferably 10 to 40 mm.
And the outer diameter is 1.00 to 7.00 mm, preferably 1.
The thickness is 50 to 5.00 mm and the wall thickness is 10 to 50 μm, preferably 15 to 45 μm.

The total length of the inner pipe 2 is 350 to 2200 mm, preferably 550 to 1700 mm, of which the tip portion 21 of the inner pipe 2 is 55 to 360 mm in length, preferably 105 to 3 mm.
10 mm, the outer diameter is 0.40 to 1.75 mm, preferably 0.50 to 1.40 mm, and the inner diameter is 0.20 to 1.50 mm.
It is 60 mm, preferably 0.30 to 1.00 mm.

The intermediate portion 22 of the inner pipe 2 has a length of 160 to 20.
00 mm, preferably 550 to 1600 mm, and the outer diameter is 0.50 to 1.85 mm, preferably 0.60 to 1.50.
mm, and the inner diameter is 0.30 to 1.70 mm, preferably 0.40 to 1.20 mm.

The base end portion 23 of the inner pipe 2 has a length of 20 to 150.
mm, preferably 25-120 mm with an outer diameter of 0.70
˜2.75 mm, preferably 1.50 to 2.50 mm, inner diameter 0.40 to 2.70 mm, preferably 0.50
~ 1.50 mm.

The transition regions of the distal end portion 11 and the intermediate portion 12, and the intermediate portion 12 and the proximal end portion 13 of the outer tube 1 are continuous with a gentle taper angle, and the length of the transition region is 5 ~
It is 70 mm, preferably 10 to 50 mm. Similarly, the transition regions of the distal end portion 21 and the intermediate portion 22, and the intermediate portion 22 and the proximal end portion 23 of the inner pipe 2 are also continuous with a gentle taper angle, and the length of the transition region is 5 It is about 70 mm, preferably 10 to 50 mm.

The opening portion 14 of the base end portion 13 of the outer pipe 1 and the opening portion 24 of the base end portion 23 of the inner pipe 2 are each processed into a flare shape, and the tip end portion 31 of the manifold 3 is respectively formed.
It is liquid-tightly fixed by a so-called caulking structure such that it is sandwiched by the base end portion 32 and the manifold main body portion 33. As the material for forming the manifold 3, for example, polyolefin, polycarbonate, polyarylate,
Thermoplastic resins such as polyamide, polysulfone, and methacrylate-butylene-styrene copolymer can be used. The front end portion 31, the base end portion 32, and the main body portion 33 of the manifold each have a screw structure, and these are joined by tightening the screws, or by heat welding or an adhesive instead of tightening these screws. It may be joined by adhesion or the like, or both may be used together.

The outer tube 1 and the inner tube 2 may be composed of two integrally formed tubular layers having different flexibility, as shown in FIGS. 6 and 7, for example. As the material of these two layers, as described above, polyolefin such as polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, polyamide, polyvinyl chloride,
Thermoplastic resin such as polyurethane, polyimide, polyamide elastomer, silicone rubber, latex rubber, etc.
The above-mentioned thermoplastic resins are preferable, and more preferable ones can be arbitrarily selected from the above-mentioned polyolefin resins. The two layers may be the same material with different flexibility, and they may be selected, for example, from the same resin with different densities and crystallinities.

When the outer tube 1 is composed of two layers, as shown in FIG.
As shown in FIG. 2, it is preferable to dispose a relatively small tubular first layer 101 on the inner surface side of the tube and a relatively large tubular second layer 102 on the outer peripheral surface of the tube. Preferably, this is to prevent bending of the tube and to construct the outer surface of the tube with a relatively soft material so as not to damage the inner surface of the blood vessel.

Further, when the inner tube 2 is composed of two layers, as shown in FIG. 7, a relatively small tubular first layer 201 on the inner surface side of the tube is provided on the outer peripheral surface of the tube. A relatively large tubular second layer 202 is preferably disposed on the
This is to prevent bending of the tube and to make the inner surface of the tube from a relatively hard material to facilitate sliding with the guide wire.

The tip 11 of the outer tube and the tip 21 of the inner tube are
As shown in FIGS. 8 and 9, the outer tube main body portion 12,
In order to make the inner tube body 22 more flexible than the inner tube body portion 22 and to facilitate the molding of the expansion body at the outer tube tip portion 11, the tubular first layer or the second layer
You may comprise only one of the layers.

Next, a method for manufacturing the catheter with an expandable body of the present invention will be described with reference to the drawings. The production method of the present invention
A step of forming a tube body forming the outer tube; a step of blow molding a flexible tip portion of the outer tube to form the expansion body; a step of forming the inner tube; and a step of forming the outer tube in the outer tube. It is composed of a step of inserting the inner tube and a step of fixing the tip part of the inner tube to the tip part of the outer tube.

Therefore, the above steps will be described with reference to the catheter with an expandable body shown in FIG. First, the step of forming the tube body forming the outer tube 1 will be described. The outer tube 1 can be formed by cutting an extruded material of the above-mentioned outer tube into a predetermined size. It may also be formed by injection molding or dipping into a male mold. Preferably, it can be formed by using the above-mentioned thermoplastic resin, for example, by using a tube extrusion molding equipment as shown in FIG. This molding equipment is basically the first extruder 51, the second extruder 5
2, pressure gas supply device 53, two-layer molding die 54, water tank 5
5, belt type take-up machine 56, cutter 57, water temperature controller 5
8 and a control device 59.

The molten resins discharged from the first extruder 51 and the second extruder 52 are joined in layers in the two-layer molding die 54 in a molten state and extruded in a tubular shape from the die tip opening. At the same time, in order to maintain the shape of the tube and control the dimensions of the tube, pressure gas is supplied from the pressure gas supply device 53 so as to communicate with the lumen of the tube from the center of the two-layer molding die 54. The tube extruded from the two-layer molding die 54 is guided to a water tank 55 and cooled in the water tank. The water temperature in the water tank 55 can be adjusted by the water temperature controller 58. The tube cooled and solidified in the water tank 55 is continuously taken by a belt type take-off machine 56 and cut into a suitable length by a cutter 57.

Each of the first extruder 51 and the second extruder 52 can control the screw rotation speed, that is, the tube material discharge amount per unit time in a stepwise manner, and at least three types corresponding to the tube wall thickness control can be used. It is possible to set a suitable value of. Further, the belt-type take-off machine 56 can also control the tube take-up speed in stages, and can set at least three kinds of suitable values corresponding to the control of the inner and outer diameters of the tube. Furthermore, the pressure gas supply device 53 that supplies the pressure gas to the lumen of the tube can also control the gas supply pressure stepwise, and at least two preferable values corresponding to both the wall thickness of the tube and the inner and outer diameter control. Can be set.

The control device 59 summarizes the operating condition setting of each of the above-mentioned first extruder 51, second extruder 52, belt type take-up device 56, and pressure gas supply device 53, and is stable and suitable by feedback control. It enables operation corresponding to various set values. That is, the first extruder 51 and the second extruder 5
By setting the respective discharge amounts of No. 2, the rotation speed of the belt type take-up device 56, and the supply gas pressure of the pressure gas supply device 53 in various appropriate combinations, tubes having various inner and outer diameters and wall thicknesses are formed. can do.

With reference to the outer tube 1 shown in FIG. 6, an embodiment of a forming method using the above-mentioned tube extrusion molding apparatus will be shown.
As the material for forming the outer tube 1, the above-mentioned materials are used. As shown in FIG. 6, the outer tube 1 may be composed of two tubular layers integrally molded with different flexibility. The materials for these two layers can be arbitrarily selected from the above-mentioned materials, preferably the above-mentioned thermoplastic resins, more preferably the above-mentioned polyolefin resins. The two layers may be the same material with different flexibility, and they may be selected, for example, from the same resin with different densities and crystallinities.

When the outer tube 1 is formed of a single material, the material is supplied to either the first extruder 51 or the second extruder 52 to extrude the molten resin. When forming from two kinds of materials, that is, in the case of forming two layers, the material corresponding to the inner layer 101 of the tube is supplied to the first extruder 51, and the material corresponding to the outer layer 102 of the tube is supplied to the second extruder 52. To extrude the molten resin.

As the method of forming the outer tube 1 shown in FIG. 6, the discharge amounts of the first extruder 51 and the second extruder 52, the rotation speed of the belt type take-up machine 56, and the operation of each device of the pressure gas supply device 53. An example of the conditions is shown in FIG. For example, the discharge amount of both the first extruder 51 and the second extruder 52 is relatively small in the thin-walled, small-diameter portion such as the tip portion 11, the rotation speed of the belt type take-up machine 56 is relatively large, and The gas supply pressure of the pressure gas supply device 53 is also relatively low.

Further, for example, in a thick wall portion such as the base end portion 13 and a large diameter portion, the discharge amount of the first extruder 51 is set relatively large, and further, the discharge amount of the second extruder 52 is set relatively large. The belt type take-up machine 56 has a relatively low rotation speed, and the gas pressure supply device 53 has a relatively high gas supply pressure.

The tip portion 11 may be composed of only the first layer or the second layer of the two tubular layers,
As an example thereof, FIG. 12 shows the operating conditions of each device corresponding to the method for forming the outer tube 1 shown in FIG. Here, the tip portion 11 is formed only from the outer layer, and the supply of the outer layer material at the time corresponding to the formation of the tip portion 11, that is, the discharge amount of the first extruder 51 is zero.

Next, with respect to the step of forming the expansion body 10 on the tip portion 11 of the outer tube 1, FIG.
It will be described based on. This step is a step based on a so-called cold parison method in a general blow molding method, and includes a step of heating the vicinity of the opening of the tip portion 11 of the outer tube 1 formed by the above method, and a heated expansion body molding portion. Is blow-molded in the expansion body molding die and brought into close contact with the inner surface of the molding die, and the step of cooling the expansion body molding portion and extracting from the expansion body molding die. Each step will be described below.

The outer tube 1 is preferably the above-mentioned thermoplastic resin,
More preferably, a polyolefin resin is arbitrarily selected and formed by the above-mentioned forming method. Then, first, a cross-linking treatment which is generally performed is performed in order to facilitate the molding of the expansion body. The cross-linking treatment can be carried out by mixing the material with a chemical cross-linking agent such as peroxide when forming the outer tube 1, and preferably by γ-ray irradiation or electron beam irradiation. In this case, the entire length of the outer tube 1 may be crosslinked, or only the tip 11 may be partially crosslinked.

Then, as shown in FIG. 13, an extension body forming die 60 having a jacket type heating / cooling mechanism at the tip portion 11 is provided.
Placed within and sealing the opening in the proximal end 13 for later blow molding. The sealing can be suitably carried out by pressing the outer peripheral surface of the tube from the lateral direction and simultaneously heating and heat welding. Further, the tip portion 11 is connected to a pressurizing device 62 such as a cylinder or a high pressure gas cylinder. As the pressurized fluid, air, nitrogen, or an inert gas such as argon can be preferably used.

The molding die 60 is connected to the heat medium temperature adjusting / supplying device 61 and can be set to any suitable temperature. The molding die 60 may have a split structure or an integral structure. In the case of a one-piece structure, the tip portion 11 is arranged in the molding die 60 before the tip portion 11 is connected to the pressurizing device 62. The expansion body molding portion of the tip portion 11 is heated in the molding die 60. In addition to this, a method of heating the molding die by induction heating, or a method of heating the tube body directly or indirectly by dielectric heating Alternatively, a method of supplying a heated pressurized fluid to the inside of the tube to heat it may be used.
Further, before the expansion body molding portion is placed in the molding die, it may be heated to a predetermined temperature at which it can be preformed externally, and then placed in the molding die and blow molded.

In the step of heating the expansion body molding portion of the distal end portion 11, it is preferable to perform the molding portion while stretching the molding portion in the axial direction. The connecting portion to the pressure device and the vicinity of the rear end portion of the expansion body molding portion are fixed and moved in opposite directions to perform stretching in the axial direction. This stretching step can be performed by arranging the expansion body forming device in the vertical direction and applying a load using a weight or the like, but more preferably, as shown in the present embodiment, both fixing portions of the tube are stepping motors. It is possible to obtain any suitable stretching speed and stretching amount by mechanically providing the slide table provided with the above.

Next, the heated / stretched expansion body forming portion supplies a pressurized fluid from the pressurizing device 62 to the inside of the tube to bring it into close contact with the inner surface of the forming die 60, and blow molding is performed. Further, subsequently, the molding die is cooled, the expansion body molding portion is sufficiently cooled to a deformation temperature or lower, and then taken out from the molding die 60. It is preferable to continuously supply the pressurized fluid until the cooling is completed. In the case where the molding die 60 has an integral structure, if necessary, the opening of the distal end portion 11 is connected to a suction pump or the like to make the inside of the tube a negative pressure, and the expansion body is contracted so that it can be easily removed from the molding die. Good.

Next, a method of forming the inner pipe 2 will be described. The inner tube 2 can also be formed by using the above-mentioned material and using the same tube extrusion molding device as that for forming the outer tube 1 described above, in the same manner as the method for forming the outer tube 1.

As shown in FIG. 7, the inner tube 2 may be formed of two integrally formed tubular layers having different flexibility. The materials for these two layers can be arbitrarily selected from the above materials, preferably the above thermoplastic resins, more preferably the above polyolefin resins. The two layers may be the same material with different flexibility, and they may be selected, for example, from the same resin with different densities and crystallinities. Further, as shown in FIG. 9, the tip portion 21 may be composed of only the first layer or the second layer of the two tubular layers.

Next, the process of inserting the inner tube 2 into the outer tube 1 and fixing the tip of the outer tube 1 and the tip of the inner tube 2 will be described with reference to FIG.
~ It demonstrates using FIG. First, the base end portion 23 of the inner pipe 2
The opening 24 of the is processed into a flare shape (Fig. 14), and the tip 2
1 from the base end side of the manifold body 33,
The flared portion is arranged so as to fit into the manifold body 33 (FIG. 15). As a method of flare processing,
It is possible to use a known method in which the opening 24 of the base end portion 23 of the inner tube 2 is pressed against a mold that matches the desired flare shape, for example, a mold or a glass mold, to heat and expand and deform the mold. .

Then, the manifold base end portion 32 is screwed into the main body portion 33 so as to sandwich the flare processing portion, and is fixed liquid-tightly by a so-called caulking structure (FIG. 16). As the material for forming the manifold 3, the above-mentioned materials can be used. In the present embodiment, the front end portion 31, the base end portion 32 and the main body portion 33 of the manifold each have a screw structure,
These are joined by tightening screws, but instead of tightening these screws, they may be joined by heat welding, bonding with an adhesive, or the like, or both may be used together.

Next, the X-ray opaque marker ring 30 is coaxially arranged on the outer peripheral surface of the distal end portion 21 of the inner tube 2 at a portion corresponding to the central portion of the expansion body 10 in the lumen of the expansion body 10. It sticks (Fig. 17). As the ring, those formed of the above-mentioned materials can be preferably used.
As a method for fixing the ring and the inner tube, for example, a method using an adhesive is used, and preferably, after the ring is arranged at a fixed position, the outer peripheral surface of the inner tube including the ring is covered with a heat shrinkable tube or the like and heated. It is possible to use a known method such as a method of fixing by contacting with each other.

Furthermore, the opening 14 of the base end portion 13 of the outer pipe 1 on which the expansion body 10 is formed is processed into a flare shape as in the case of the above inner pipe, and the inner pipe connected to the manifold main body 33 is formed. The distal end portion 21 of No. 2 is inserted from the opening portion 14 side, and the flared portion is arranged so as to cover the manifold main body portion 33 (FIG. 18). And the manifold tip 3
1 is screwed to the main body portion 33 so as to sandwich the flared portion, and is fixed liquid-tightly by a so-called caulking structure (FIG. 19).

Finally, the opening of the tip 21 of the inner tube 2 is fixed to the opening of the tip 11 of the outer tube 1. Any fixing method may be used as long as it can be fixed liquid-tight while maintaining the shape of the tip 40. For example, a method using an adhesive or a method of heat welding is preferably used. In the present embodiment, the latter method is used, and the core material 4 having a diameter substantially the same as the inner diameter of the lumen of the tip 40 can be retained.
1 is inserted, and an elastic tube 42 made of, for example, silicone rubber is fitted on the outer peripheral surface of the tip 40 so that it can be pressed evenly from the outer peripheral surface, and then fixed by heating from outside with warm air or the like. (Fig. 20).
Alternatively, a heat shrink tube made of polytetrafluoroethylene (PTFE) or the like may be used.

As the above heat welding method, a mold made of metal or glass may be used, a high frequency oscillation electrode may be provided on the metal mold for heating, and ultrasonic waves may be used. . Further, in the above-described embodiment, a metal material is used as the core material 41 for holding the inner diameter, and the core material 41 is heated by high frequency induction heating instead of heating from the outside by warm air, and heating from the inside is performed. Can also be used.

After the tip 40 is fixedly formed in the above step, the tip 40 may be processed so as to have a tapered outer diameter toward the tip opening and to have a curved tip. preferable. For this purpose, the tip 4 should be attached to a mold that matches the desired tip shape, such as a mold or glass mold.
It is possible to use a known method such as pressing 0 to deform by heating.

[0057]

The catheter with an expandable body of the present invention is a catheter with an expandable body in which an outer tube and an inner tube are coaxially arranged,
The outer tube is composed of a flexible tip portion, a middle portion having an inner and outer diameter larger than the tip portion, and a thick base end portion having an inner and outer diameter larger than the middle portion. Since it has a foldable expansion body and is seamlessly molded from the distal end portion including the expansion body to the base end portion and has a seamless structure, the expansion body is formed as a separate body and a secondary body is formed. As in the case of joining by a processing means, there is no need to always suspect the completeness of liquid tightness of the joining portion, and there is a possibility that steps, scratches or fluffing may occur on the outer surface of the catheter including the joining portion. There is no possibility of damaging the blood vessel of the patient.

Further, not only the bending preventing tube which is conventionally used is not required at each of the proximal ends of the outer tube and the inner tube of the catheter tube, but also the boundary portion between the bending preventing tube and the catheter tube is not required. Since it does not exist, there is no fear that stress will be concentrated on the boundary portion due to abrupt change in outer shape and bending will occur there.

Further, in the method for manufacturing a catheter with an expandable body of the present invention, the step of forming the tube body forming the outer tube and the flexible tip portion of the outer tube are blow-molded to form the expandable body. A step of forming the inner tube, a step of inserting the inner tube into the outer tube, and a step of fixing the tip part of the outer tube and the tip part of the inner tube, and particularly the outer tube. As for the expansion body, the distal end, the intermediate part, and the base end of the catheter tube body are all molded smoothly and seamlessly, and as the inner tube, the distal end, the intermediate part, and the base end are all smooth. By integrally molding and making it seamless, the number of steps for assembling the entire catheter with an expandable body is small and easy, and further, there is no risk of damaging the inside of the blood vessel and bending of the catheter with the expandable body. Le can be easily manufactured.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of a catheter with an expandable body of the present invention.

FIG. 2 is an enlarged sectional view taken along line AA of FIG.

FIG. 3 is an enlarged sectional view taken along line BB of FIG. 1;

FIG. 4 is an enlarged sectional view taken along line CC of FIG. 1;

FIG. 5 is an enlarged sectional view taken along line DD of FIG. 1;

FIG. 6 is a vertical sectional view showing an example of an outer tube.

FIG. 7 is a vertical sectional view showing an example of an inner pipe.

FIG. 8 is a vertical sectional view showing an embodiment of an outer tube.

FIG. 9 is a vertical cross-sectional view showing an example of an inner pipe.

FIG. 10 is an explanatory view showing an example of an apparatus for manufacturing a catheter with an expandable body of the present invention.

FIG. 11 is a vertical cross-sectional view of an outer pipe (an example in which the outer pipe is composed of two layers) and an explanatory diagram showing a control pattern of molding equipment.

FIG. 12 is a vertical cross-sectional view of the outer tube (the outer tube is composed of two layers,
It is explanatory drawing which shows the example which a front-end | tip part is comprised from only one layer, and the control pattern of molding equipment.

FIG. 13 is an explanatory diagram showing an example of an expansion body manufacturing apparatus.

FIG. 14 is an explanatory view of the manufacturing process of the catheter with an expandable body of the present invention.

FIG. 15 is an explanatory view of the manufacturing process of the catheter with an expandable body of the present invention.

FIG. 16 is an explanatory diagram of a manufacturing process of the catheter with an expandable body of the present invention.

FIG. 17 is an explanatory view of the manufacturing process of the catheter with an expandable body of the present invention.

FIG. 18 is an explanatory view of the manufacturing process of the catheter with the expandable body of the present invention.

FIG. 19 is an explanatory view of the manufacturing process of the catheter with an expandable body of the present invention.

FIG. 20 is an explanatory diagram of the manufacturing process of the catheter with an expandable body of the present invention.

[Explanation of symbols]

1 Outer Pipe 2 Inner Pipe 3 Manifold 10 Expander 30 Marker Ring 40 Tip 41 Core Material 42 Elastic Tube 51 First Extruder 52 Second Extruder 53 Pressure Gas Supply Device 54 Two-layer Forming Die 55 Water Tank 56 Belt Type Take-out Machine 57 Cutter 58 Water temperature controller 59 Control device 60 Mold 61 Heat medium temperature control / supply device 62 Pressurizing device 63 Slide table

Claims (9)

[Claims] 1. A catheter with an expander in which an outer tube and an inner tube are coaxially arranged, wherein the outer tube has a flexible tip portion, an intermediate portion having an inner and outer diameter larger than the tip portion, and a portion further than the intermediate portion. It has a large-inner-outer diameter and a thick-walled base end portion, and the front end portion has an expandable body that can be contracted or folded, and the end body including the expandable body and the base end portion are seamless and smooth. A catheter with an expandable body, characterized in that it is integrally molded into the. 2. The catheter with an expandable body according to claim 1, wherein the outer tube has a portion composed of two integrally formed tubular two layers having different flexibility. 3. The outer tube is formed by integrally molding a tubular first layer having a relatively small flexibility and a tubular second layer having a relatively large flexibility on an outer peripheral surface of the first layer. The catheter with an expandable body according to claim 1 or 2, which has a portion constituted by two layers. 4. A tip portion of the outer tube is formed of only the tubular first layer or second layer.
The catheter with an expandable body according to any one of 3 to 3. 5. The inner tube is composed of a flexible tip portion, a middle portion having an inner and outer diameter larger than the tip portion, and a thick-walled base end portion having an inner and outer diameter larger than the middle portion. The catheter with an expandable body according to any one of claims 1 to 4, wherein the catheter is molded integrally and smoothly from the portion to the base end portion without a seam. 6. The catheter with an expandable body according to claim 5, wherein the inner tube has a portion formed of two integrally formed tubular two layers having different flexibility. 7. The inner tube is formed by integrally molding a tubular first layer having a relatively small flexibility and a tubular second layer having a relatively large flexibility on an outer peripheral surface of the first layer. The catheter with an expandable body according to claim 5 or 6, which has a portion constituted by two layers. 8. The distal end portion of the inner pipe is composed of only one of the tubular first layer and second tubular layer.
7) A catheter with an expandable body according to 7. 9. An outer pipe and an inner pipe are arranged coaxially, and the outer pipe has a flexible tip portion, an intermediate portion having an inner and outer diameter larger than the tip portion, and an inner and outer diameter larger than the intermediate portion. It is composed of a thick base end, and has an expandable body which can be contracted or folded at the distal end, and is integrally and smoothly molded from the distal end including the expandable body to the base end. A method of manufacturing a catheter with an expandable body, comprising the steps of forming a tube body forming the outer tube, forming the expandable body by blow molding a flexible tip portion of the outer tube, Manufacture of a catheter with an expandable body, which comprises a step of forming a tube, a step of inserting the inner tube into the outer tube, and a step of fixing the distal end portion of the outer tube and the distal end portion of the inner tube. Method.