JP2721639B2 - Small diameter medical tubing - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a small-diameter medical tube which is used by being inserted into a blood vessel or the like, and more particularly to a tube having an improved pressure resistance against internal pressure without increasing the wall thickness of the tube. The present invention relates to a small-diameter medical tube capable of suppressing a dimensional change in a direction.

[0002]

2. Description of the Related Art As a medical tube widely used for diagnosis or treatment, there is, for example, a tube constituting a catheter. Since the catheter is introduced to a diseased part in the body via a blood vessel or the like, as a characteristic of a tube used for the catheter, an operation such that the distal end can easily reach a target diseased part after being inserted into a blood vessel or the like. It is required to have a pressure resistance so as not to change its dimensions even when subjected to a pressure or the like due to injection of a chemical solution during diagnosis or treatment.

[0003] For this reason, the medical tubing is usually made of plastic. However, in order to obtain the above-mentioned operability and pressure resistance, it is common to form a tube wall by combining a reinforcing member. I have. In recent years, diagnosis and treatment of blood vessels or distal ends of body cavities have been performed, and the outer diameter is small and the inner diameter is as large as possible. Demands are increasing, although torque is good.

[0004] Conventional medical tubes that meet such demands are disclosed in, for example, JP-A-61-228877, JP-A-3-141958, and JP-A-3-16947.

A thin-walled small-diameter catheter disclosed in Japanese Patent Application Laid-Open No. 61-228877 has an elongation modulus of 3% inside a tube wall made of polyvinyl chloride, polyurethane, silicone rubber or the like, and 70% or more when expanded. It is configured using a medical tube in which non-metallic fibers are spirally embedded. In this medical tube, kink resistance, flexibility, and crush recovery are improved as characteristics of the tube.

A catheter disclosed in Japanese Patent Application Laid-Open No. 3-141958 has a lumen formed therein, a rigidity-imparting body formed in a mesh shape by a linear body, and provided in parallel with the lumen and extending in the axial direction. It is configured using a medical tube having a reinforcing body formed of a linear body.
In this medical tube, bending is prevented by the rigidity imparting member, torque transmission is enhanced, and meandering in the body cavity is prevented by the reinforcing member.
The pushing force given at the base end is reliably transmitted to the tip.

Further, a non-joint torque transmitting catheter for medical use disclosed in Japanese Utility Model Laid-Open No. 3-16947 is a high-density polyethylene extruded in a hollow, coated with a low-density polyethylene having a low melting point, and a stainless steel as a torque transmitting portion on the outer periphery. A steel wire or a carbon wire is buried in low-density polyethylene by arranging the wire in a heated state, and a Kevlar fiber or a carbon fiber as a reinforcing layer is further provided on the outer periphery thereof.
It is configured using a medical tube which is wound horizontally from the direction and the outermost circumference is covered with a thermoplastic plastic. In this medical tube, since the torque transmitting portion is provided along the longitudinal direction of the stainless steel wire or the carbon wire, the working efficiency is improved, and the reinforcing layer is provided by horizontally winding the Kevlar fiber or the carbon fiber from the left and right directions. since it is possible to fine-diameter reduction.

[0008]

However, the medical tube described above has the following problems. (1) JP-A-61-228877 Since the fibers of the thermoplastic resin are helically embedded in the tube wall at an interval of 1 mm or less, the length of the tube wall in the longitudinal direction accompanying the rise in the pressure of the hollow portion is reduced. Cannot be regulated. This elongation varies depending on the material of the tube wall, but when the thickness of the tube wall becomes 0.35 to 0.40 mm or less, most of the tendency is exhibited, the outer diameter of the hollow portion becomes thinner, It becomes more noticeable as the thickness decreases. (2) JP-A-3-141958 Since the rigidity imparting body in the tube wall is formed in a mesh shape, the linear body is doubled at the mesh portion, and furthermore, the linear reinforcing body is embedded. These overlaps are tripled and the thickness of the tube wall is inevitably increased. Therefore, it is not possible to meet the demand for a thinner or extremely thin wall. on the other hand,
Excluding the linear reinforcement, that is, if the tube wall is made only of a mesh reinforcement, the tube wall can be thinned and the diameter can be reduced, but as described above, the pressure in the hollow portion is reduced. The rise causes the tube wall to extend in the longitudinal direction. (3) Japanese Utility Model Laid-Open No. 3-16947 A stainless steel wire or carbon wire is laid vertically on low-density polyethylene, and Kevlar fiber or carbon fiber is wrapped around the outer periphery of the tube from two directions. The thickness of the body is so large that it cannot meet the demand for thinner diameter or ultra-thin wall, and in order to realize the thinner wall of the tube, the wall of the tube is deformed in the longitudinal direction. .

Accordingly, an object of the present invention is to provide a medical tube capable of improving pressure resistance without increasing the wall thickness of a tube wall and suppressing a dimensional change in a length direction.

[0010]

The present invention achieves the above object.
In order to achieve this, a thermoplastic plastic
Consisting of ultra-thin tube wall made of stick resin
Adhesive layer made of thermoplastic resin on the outer periphery
Is coated inside the tube wall body
Embedded in parallel along the hollow part and
In particular, the machine fiber is integrated with the tube wall.
The present invention provides a small-diameter medical tube.

[0011]

[0012] The tube wall has an inner layer wall made of Shore A hardness of 90 or more thermoplastic resins, is composed of an outer layer wall made of thermoplastic resin of less than Shore A hardness of 90, wherein the organic fibers, The inner wall
The structure embedded between the body and the outer layer wall is preferable.

[0013]

[0014]

EXAMPLES Hereinafter, will be described in detail with reference to the accompanying drawings thin medical tube of the present invention.

1 and 2 show a cross-sectional structure of a medical tube 1 according to one embodiment of the present invention. This medical tube (hereinafter, referred to as a tube) 1 is composed of a tube wall 2 made of a thermoplastic resin having a hollow portion 4, and the wall thickness of the tube wall 2 is 0.10 to 0.35.
mm, the inner diameter of the hollow portion 4 is 0.3 to 1.3 mm, and the finish outer diameter is 0.8 to 2.0 mm. (3) linear fibers 3 are embedded.

As the thermoplastic plastic constituting the tube wall 2, polyurethane having a Shore A hardness of 80 is applied. In addition, a polyolefin-based elastomer using polyethylene, polypropylene, ethylene-vinyl acetate copolymer, ethylene-propylene copolymer, or the like, polyvinyl chloride, polyamide-based elastomer, polyester-based elastomer, polyurethane, or the like may be used. good.

The linear fiber 3 is immersed in a 2% by weight solution of polyurethane having a Shore A hardness of 80 in tetrahydrofuran for about 5 seconds, and an adhesive coat 3B is applied to the outer periphery of the fiber 3A as shown in FIG. And semi-dried at 80 ° C. for 2 minutes. The linear fibers 3 are inserted into the tube wall forming nipple portion of the extruder at the time of extrusion forming of the tube wall 2, and are melted in the adhesive coat 3 </ b> B by the heat of the extrusion forming to form the tube wall inside the tube wall 2. 2 and bonded together. At this time, since the linear fibers 3 need to be converged on the tube wall 2 and arranged as flat as possible with a small outer shape, a predetermined value of back tension is applied at the time of coating the adhesive coat 3B or at the time of extrusion molding. In addition, it is preferable that the insertion port of the nipple portion to be used is formed in a paper-like shape as much as possible.

The fiber 3A has low elongation, high tensile strength, flexibility, and has a converging force (a material that easily converges and changes its shape when an external force is applied). It is preferable that the flexibility of the tube wall 2 is not impaired even when the tube wall 2 is buried in the tube wall 2. In this embodiment, 50 denier polyarylate fiber (trade name: Vectran Kuraray), which is an organic fiber, is applied. ing. In addition, polyamide fibers (Kevlar Dupont) may be used. Those that cannot be used are carbon fibers and metal fibers.Carbon fibers are inapplicable because they lack flexibility and impair the flexibility of the tube wall. Even if it is buried in the tube wall 2 while maintaining it, it does not converge and is exposed to the outside, so it is not applicable.

The medical tube of this embodiment is
Although it has been described that the linear fibers 3 are embedded in the polyurethane resin tube wall 2 having a thickness of 0.01 to 0.35 mm, when the tube material is a polyester elastomer, the linear fibers 3 It is preferable to use a polyester hot-melt resin (trade name: PES-140 Toa Gosei), which is a resin of the same family, as the adhesive coat 3B.

FIGS. 4 and 5 show a sectional structure of a tube 1 according to a second embodiment of the present invention. In this embodiment, the flexibility and torque of the tube 1 shown in FIGS. 1 and 2 are improved, and the tube wall 2 is made up of two layers, an inner wall 5 and an outer wall 6, and between the layers. In this case, linear fibers 3 are embedded.

The inner wall 5 is formed by extruding a polyurethane resin having a Shore A hardness of 90 or more with an inner diameter of 0.6 mm and an outer diameter of 0.7 mm, and then polishing the outer surface or applying an adhesive coat. ing. When polishing the outer surface of the inner layer wall 5 is a linear fiber 3 performs similarly bond coat as in Example 1 but, when subjected to direct bonding coat inner wall outer surface, linear The adhesive coat may be omitted for the fibers . Reason for limiting inner layer wall to Shore A hardness 90 or more
Is the tubing's pressure resistance and dimensional change in the length direction (extensibility)
In particular, the outer diameter of the tube and the tube
If the wall thickness is small, make the inner layer wall 90 or less,
The tube itself becomes softer and hinders subsequent work.
At the same time, pressure resistance and extensibility cannot be maintained.
You.

The outer layer wall 6 has a thickness of 0.15 mm and an outer diameter of 1.0 m while linear fibers 3 are arranged along the outer periphery of the inner layer wall 5.
It is constituted by extrusion-coating a polyurethane resin having a Shore A hardness of less than 90 and a linear fiber 3 and an inner layer wall 5 via an adhesive coat (not shown). In this embodiment, the linear fibers 3 are buried between the inner wall 5 and the outer wall 6, but they may be buried in either the inner wall or the outer wall. Outer wall is limited to Shore A hardness less than 90
The reason is to maintain the flexibility of the tube,
The capacity of the outer wall relative to the entire tube is greater than the inner wall
Become larger, and if it is more than 90, the hardness of the whole tube
Will rise, and it will lack flexibility.

[0023]

[0024]

[0025] In the above configuration, to more clarify the invention, against the embodiments, discussed the differences in their properties by creating a following tube as a comparative example. (1) Comparative Example 1 A polyurethane resin having a Shore A hardness of 80 and an inner diameter of 0.6 m
m, an outer diameter of 1.0 mm and a wall thickness of 0.2 mm were prepared. (2) Comparative Example 2 A stainless steel wire (SUS316) having a diameter of 0.06 mm was embedded in the wall of the tube of Comparative Example 1. (3) Comparative Example 3 A polyurethane resin having a Shore A hardness of 80 and an inner diameter of 1.2 m
m, an outer diameter of 1.7 mm and a wall thickness of 0.2 mm in a tube wall of a stainless steel wire having a diameter of 0.04 mm (SU
A braided reinforcement (1 support x 24 hits) using S316) was embedded.

In the discussion, the following test items were implemented. (1) Irregularities of appearance Irregularities on the outer surface of the tube were visually checked. (2) Flexibility When a loop was formed in the tube and the loop was made smaller, the loop diameter at the time when the tube kinked was measured. (3) Extensibility A 1m mark is attached to the tube, and 500g, 100
The elongation when a vertical load of 0 g was applied was examined. Elongation was determined by the following equation. (4) Adhesion The tube was bent 100 times with a diameter of 10 mm, and the adhesion between the wall at the bent portion and the reinforcing member was checked.

[Table 1]

As can be seen from the test results in Table 1, the tubes of Examples 1 and 2 according to the present invention have small and stable extensibility, good flexibility and good adhesion, and good tube appearance. It has become.

That is, the medical tubes of the first and second embodiments have the following functions and effects. (1) Since the linear fiber is composed of a collection of many small fibers, it is converged by the way of applying tension and external force and the guide form and changes into a thin paper form. Also, it is not necessary to increase the thickness of the tube wall. (2) When an organic fiber is used as the linear fiber, the elongation in the length direction is extremely small, and since it has flexibility, it is easily changed by tension and external force. Can also be buried. (3) By embedding linear fibers (organic fibers) in the thin and extremely thin tube wall, it is possible to prevent the tube wall from extending in the length direction due to pressure. (4) Since the linear fiber has the same adhesive coat as the plastic forming the tube wall on the outer periphery of the fiber, it can be surely integrated with the tube wall. (5) When the tube wall has two layers, a Shore A hardness of 90
An inner layer wall body made of the above thermoplastic resin,
It is composed of an outer layer wall made of the same resin having a Shore A hardness of less than 90, and since linear fibers are embedded between the layers, the inner layer wall has pressure resistance, and the outer layer wall has flexibility,
The linear fibers can prevent elongation in the length direction .

[0029]

As described above, according to the small-diameter medical tube of the present invention, the tube is made of an extremely thin wall made of a thermoplastic resin having a hollow portion with a predetermined diameter, and the outer periphery is made of heat. Adhesion made of plastic resin
The coated organic fiber is hollow inside the tube wall
The organic fibers are buried in parallel along the
Since the tube wall is integrated, the dimensional change in the longitudinal direction can be suppressed without increasing the wall thickness of the tube wall. As a result, when this tube is applied to a catheter, it can be properly inserted into the diagnosis or treatment area, and accurate diagnosis or treatment can be performed while reducing the patient's pain during diagnosis or treatment. Can be.

[Brief description of the drawings]

FIG. 1 is a front sectional view showing one embodiment of the present invention.

FIG. 2 is a side sectional view showing one embodiment of the present invention.

FIG. 3 is a sectional view showing a linear fiber according to one embodiment.

FIG. 4 is a front sectional view showing a second embodiment of the present invention.

FIG. 5 is a side sectional view showing a second embodiment of the present invention .

[Explanation of symbols]

1 fibers of the tube body 2 Tube wall 3 linear 4 hollow portion 5 the inner wall 6 outer wall

Claims (2)

(57) [Claims] 1. An adhesive layer comprising an extremely thin tube wall made of a thermoplastic resin having a hollow portion with a predetermined inner diameter and having an outer periphery made of a thermoplastic resin.
The organic fiber coated with is embedded in the inside of the tube wall in parallel along the hollow portion, and the organic fiber is covered with the adhesive layer.
A small-diameter medical tube, wherein machine fibers are integrated with the tube wall . 2. The organic fiber according to claim 2, wherein the tube wall comprises an inner wall made of a thermoplastic resin having a Shore A hardness of 90 or more, and an outer wall made of a thermoplastic resin having a Shore A hardness of less than 90. The small-diameter medical tube according to claim 1, wherein the tube is embedded between the inner wall and the outer wall.