JPH08196619A - Cathether tubular member - Google Patents

Abstract

PURPOSE: To provide a cathether tubular member which is smoothly and quickly inserted into a living body and easily drawn out without being accompanied by pain even when the inserting distance into the body is long, by forming the cathether tubular member from a seamless tube body whose main component is a thermoplastic polyimide resin. CONSTITUTION: A cathether tubular member is formed by a seamless tube body whose main component is a thermoplastic polyimide resin. Concretely, it is formed by the seamless tube body which contains 55∼95 weight % of thermoplastic polyimide resin and 45∼55 weight % of polyetheretherketone resin. This tube body has a tapered shape so that the at least tip part is narrowed toward the head part, and Young's modulus of the tube body is in the range of 10000 to 50000kg/cm<2> . Thereby, it can be inserted into the living body quite smoothly and quickly without being accompanied by pain and can be drawn out smoothly and quickly even when the inserting distance into the body is long.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tubular member for catheter having appropriate flexibility, strength and rigidity.

[0002]

2. Description of the Related Art A catheter is a hollow medical instrument that is inserted into a cavity, a tube, a blood vessel, etc., and is used for injecting and inhaling a liquid, securing a passage, etc., and usually has a thin tube body. . Such a catheter tube is basically required to have appropriate flexibility, but mechanical strength and appropriate rigidity are also required because it does not break during insertion, withdrawal, position adjustment, and the like. Conventionally, in consideration of these requirements, many materials such as various elastomers, thermoplastic polyurethanes, and fluoropolymers have been used as the material. Conventionally, when injecting a liquid into a body, aspirating, etc. using a catheter, it is usually desired to perform it quickly, and in order to solve the problem, the inner diameter of the tube is generally made large.

[0003]

Although the materials for catheters are used satisfactorily for their respective purposes and uses, there are some situations in which they cannot follow the recent advances in medical technology. For example, when a microcatheter is inserted from a crotch vein and a contrast agent is injected into the brain when performing X-ray imaging of the brain, the distance is about 2 m, so that the material for this catheter tube is conventionally As mentioned above, olefinic elastomers such as polyethylene, thermoplastic polyurethane, etc. are used, but catheters made of these materials bend when pushed into the body, and it is difficult to enter, and there is a problem that they are cut when withdrawn. There is a situation where it cannot be used with confidence. This depends on the characteristics of the material itself, but it is also necessary to use an extremely thin tube and that the tip portion of the tube is thin, that is, a tapered tube is used. The solution to this problem is basically to be as thin and flexible as possible, but it is more effective to use a tube having mechanical strength and appropriate rigidity.

The measures for increasing the inner diameter of the tubular member for the purpose of promptly injecting, sucking, and discharging the liquid into the body by the catheter have the following problems. That is, in the conventional material, if the inner diameter is increased, the outer diameter is inevitably increased. This is to provide appropriate strength and rigidity. If the outer diameter increases, the piercing resistance when inserting into the body, the pulling resistance when taking out conversely, and the resistance when adjusting the position (moving) inside the body will increase, so in such cases , Pain, discomfort, and physical and mental distress. Therefore, there is a strong demand for a tube body having a larger inner diameter, a smaller outer diameter and suitable flexibility, strength and rigidity for a catheter.

Therefore, the present inventors have addressed the above-mentioned problems.
Based on the conventional tube material, we examined modification by blending and change of hardness (appropriately hard),
None of them found anything satisfying all. However, in the process of study here, it was found that it is possible to provide a catheter with better quality than the conventional one by taking measures such as thinning the tube thickness even with hard resin. As a result of further study, the present invention was finally reached.

[0006]

That is, the present invention provides a tubular member for a catheter comprising a seamless tubular body containing a thermoplastic polyimide resin as a main component, and further 95 to 55% by weight of the polyimide resin. The present invention provides a seamless tube body containing 5 to 45% by weight of polyether ether ketone as a tubular member for a catheter. The structure of the present invention will be described in more detail below.

First, in the present invention, the catheter is useful for the purpose of injecting blood, drug solution or the like into the body as described above, or conversely, for sucking or discharging secretory fluid, blood or the like from the body, It can also be used with a visual function. In addition, it can be used not only as a human body but also as various catheters for animals, and can also be used for industrial endoscopic catheters and the like, and its applications are widespread in all fields.

The thermoplastic polyimide resin used in the present invention is generally a polycondensation reaction of a tetracarboxylic dianhydride and an organic diamine in an organic polar solvent such as dimethylacetamide to pass through a polyamic acid and finally Among the polyimides obtained by ring-closing imidization, it means a polymer which has the property of softening or melting by heating and which can be extruded. Therefore, polyimides that cannot be extruded, ie, melt-formed by heating, are excluded from the present invention.

The reason why the above-mentioned thermoplasticity is imparted to the polyimide depends on the kind of the tetracarboxylic dianhydride or / and the organic diamine as the starting material. That is, when an acid anhydride group or a group (aromatic group) to which an amino group is bonded is bonded by an aliphatic hydrocarbon, an oxygen atom, a carbonyl group or the like and has a long linear structure, a thermoplastic polyimide resin is easily obtained. Specifically, for example, pyromellitic dianhydride and 4,
Combination with 4'-bis (3-aminophenoxy) bisphenyl 3,3 ', 4,4'-bisphenyltetracarboxylic dianhydride and bis [4- {3- (4-aminophenoxy) benzoyl. } Phenyl] ether in combination,
A combination of 3,3 ′, 4,4′-benzophenone tetracarboxylic dianhydride and 3,3′-diaminobenzophenone, and further isopropylidene bis- (4-phenyleneoxy-4-phthalic acid) dianhydride. An example is a thermoplastic polyimide obtained by combining with 2,2'-phenylenediamine and the like, and these are usually softened or melted by heating at around 400 ° C, and therefore extrusion molding is possible. More specifically, it is marketed as a thermoplastic polyimide resin, for example, ULTEM1 manufactured by GE.
000, K-POLYMER manufactured by Du Pont, AURUM or LARC-TPI manufactured by Mitsui Toatsu Chemicals, Inc., and the like. Among them, AURUM (also referred to as New-TPI) can be mentioned as a material which is more excellent in extrusion moldability. Some grades have a glass transition point of 250 ° C and a melting point of 388 ° C.

Such a thermoplastic polyimide resin is used for a catheter as a seamless tube body, and such a seamless tube body can be produced by a conventional extrusion molding method, for example, from an annular die. For example, a method of extruding from a ring die in a softened or molten state from a single-screw or multi-screw type extruder and then taking it as it is while cooling, a method of taking it out while applying tension, and the like can be exemplified. The tube body according to the present invention has a larger inner diameter and a smaller outer diameter, that is, it is possible to make the wall thickness thinner.For this purpose, a method of pulling while controlling the dimensions by an inside mandrel or the like, extrusion, after pulling,
For example, a stretching method may be used. In any case, during extrusion, it is more preferable to feed air from the center of the annular die and regulate the dimensions by air pressure. This is effective for forming a smaller tube, that is, a tube having a smaller inner diameter. It should be noted that this method can also be performed in association with the above method. However, the manufacturing method is not particularly limited.

At this time, the wall thickness of the tube can be reduced by stretching, but the stretching is, for example, about 250-3.
Since the film can be stretched in the axial direction and / or the circumferential direction up to an appropriate ratio, preferably about 2 times, at a temperature of 50 ° C., the ratio may be determined in consideration of the thickness, flexibility, rigidity and the like when stretching.

According to the molding method described above, the wall thickness,
Various inner and outer diameters can be manufactured. For example, a tube having a wall thickness of about 10 μm and an outer diameter of about 100 μm can be easily manufactured. The wall thickness is not particularly limited because it depends on the outer diameter of the tube, but generally 1
000 to 10 μm, preferably about 500 to 20 μm can be set as a suitable range. The Young's modulus, which is a tentative guide for the appropriate flexibility and the appropriate rigidity of the tube, may be 10,000 to 50,000 kg / cm ² , preferably 18,000 to 50,000 kg / cm ² . Of course, there is no problem even if it exceeds this range.

The thermoplastic polyimide tube is superior to any other resin in moderate flexibility, flex resistance, rigidity and toughness, but is slightly flex resistant, that is, it is pushed into the body while bending. , There is a risk of breaking as the frequency of use increases and decreases. Completely eliminating this risk is also extremely important. Therefore, in the present invention, polyetheretherketone is particularly selected, and it is added to the resin component in an amount of 5 to 5.
45% by weight, preferably 10-40% by weight,
This can be achieved by using it in a catheter as a tube body obtained by extrusion molding as described above. At this time, the mixing amount of the thermoplastic polyimide resin is 95 to 5 with respect to the resin component.
It is 5% by weight, preferably 90-60% by weight.

Here, the polyether ether ketone is an IC
3. 4.4'-phenylenediol developed by Company I and 4.
A crystalline polymer having a melting point of 334 ° C. obtained by a polymerization reaction with 4′-cifluorobenzophenone can be exemplified. Therefore, extrusion molding is possible like thermoplastic polyimide. Among many highly functional resins, polyetheretherketone is particularly selected because it has excellent compatibility with thermoplastic polyimide and can be extruded into a tubular body well. This is because the bending resistance of the tube body is improved. Although the reason for further improvement in flex resistance is not clear, it is considered that the compatibility with thermoplastic polyimide is good and the flex resistance due to the molecular structure of polyether ether ketone is imparted.

This improvement in bending resistance is also achieved by mixing the polyether ether ketone in an amount of 5 to 45% by weight, as described above.
The most effective effect is preferably 10 to 40% by weight.
That is, if it is less than 5% by weight, the substantial improvement effect is not remarkable, and if it exceeds 45% by weight, the rigidity is lacking, and conversely, it tends to bend and there is a risk of breaking during use, which is not preferable.

The extrusion molding conditions when the polyether ether ketone is mixed may be exactly the same as those for the thermoplastic polyimide. This is because they are similar in terms of physical properties and heat. The size and shape of the obtained tube body can be the same as the tube body made of the polyimide. The tube body according to the present invention is a thermoplastic polyimide resin, in addition to the above-mentioned polyether ether ketone, various thermoplastic resins and various additives, if necessary, within a range that does not significantly deteriorate the properties of the tube body. There is no problem in adding the three components.

In many cases, the tubular member for a catheter has a constant inner and outer diameters, but a catheter called a microcatheter is required to have a resistance to pierce into the body and to be easily inserted. In particular, it is often the case that the insertion tip portion is tapered so that it has a thinner shape. On the contrary, in many cases, it is often difficult to insert the conventionally used tapered catheter, but this is considered to be due to lack of strength and rigidity. However, the one using the thermoplastic polyimide resin of the present invention, even a tapered tube body, more easily into the body with a small piercing resistance,
Can be inserted deeply. This is because even if the outer diameter is small and the wall thickness is thin, it has appropriate strength and rigidity, and by making the wall thickness thinner, it is possible to impart appropriate flexibility.

The tapered tube body may be tapered from the base end to the distal end, but it is not always necessary that the entire tube body is tapered. At least at the tip (for example, within about 300 mm),
A tapered shape may be used so that the leading edge becomes thin. Therefore, the other portions may have the same inner and outer diameters.

Although there is no specific method for manufacturing such a tapered tube body, the following is an example. As a method of continuously using the above-mentioned annular die, the length of the tube to be tapered is determined in advance, and the tube discharged between the lengths is continuously accelerated and drawn. Next, during that length, the yarn is continuously taken toward the initial velocity while decelerating continuously. This is set as one cycle, and thereafter, acceleration and deceleration are repeated in the same manner. The inner diameter and taper angle of the tube obtained here are mainly determined by the acceleration and deceleration speeds. More concretely, it will be described in Examples described later.

On the other hand, it is also possible to manufacture in batch.
In this, a tube having the same diameter obtained by preforming by the above-described method is fitted into a tapered form frame (made of metal or the like), and the whole is heated to about 250 to 350 ° C.
If the tube used in this case is stretched, it only needs to be heated. This is because when it is shrunk by heating, it is deformed into a taper shape. When the tube is not stretched, the proximal end portion of the inserted tube is fixed and the distal end portion is positively pulled. The heating temperature for pulling is about 250 to 350 ° C., but it is desirable to make a temperature gradient so that the temperature gradually increases toward the tip.

The catheter having the tube body constructed as described above can be smoothly inserted even with a long insertion distance from the vein of the hip to the brain. Therefore, pain and discomfort are greatly reduced. This is because the tube body is formed with a smaller size and a thinner wall thickness, and yet retains appropriate strength and rigidity. On the contrary, even when the function is pulled out, the function is smoothly and comfortably performed, and of course, there is no fear of refracting during these operations and interrupting the medical treatment.

Further, when injecting or sucking the liquid, it can be carried out quickly, but this is because the tube body can be made thinner and the inner diameter can be made larger.

With regard to pain, it is said that it depends largely on rigidity, and since the thermoplastic polyimide resin according to the present invention is considerably more rigid than other thermoplastic resins, it is likely to be accompanied by pain, but The tube body of the present invention has almost no pain as in the case of the conventional thermoplastic elastomer tube body. This cause is because it is possible to make the wall thickness of the tube body a pole in the present invention, in other words, when it becomes thin, the apparent rigidity becomes smaller, and by this amount, moderate flexibility that does not become fluffy. It is considered that the pain is imparted, the insertion and the removal are facilitated, and the pain is less.

[0024]

EXAMPLES The present invention will be described in more detail below with reference to Examples along with Comparative Examples.

Example 1 A single-screw type extruder having an annular die attached to the discharge tip was prepared, and a thermoplastic polyimide resin (Mitsui Toatsu Chemical Co., Ltd. AURUM) was extrusion molded into a tubular body. Got In this molding, the barrel temperature of the extruder is 380 to 410 ° C., the temperature of the annular die is 395 ° C., the slit spacing of the annular nozzle is 0.45 mm (outer diameter 4.6 m).
m, inner diameter 3.7 mm), and air was fed from the center of the die. At this time, the take-up speed was set to 23 m / mm. The tube thus obtained had an outer diameter of 0.8 mm and a wall thickness of 125 μm.

Comparative Example 1 A tube body was extruded in the same manner by using a copolymer of ethylene-propylene rubber (EPDM) and propylene instead of the thermoplastic polyimide resin of Example 1. At this time, the barrel temperature of the extruder was 190 to 220 ° C and the die temperature was 220 ° C. The outer diameter of the obtained tube is 0.8
The thickness was 5 mm and the thickness was 110 μm.

Next, each of the obtained tube bodies is set to 500 m.
The length was cut into m and the ease of insertion was compared. The comparative test was carried out by using a dog, and inserting a hollow needle into the vein of the forepaw and inserting a tube through the hollow needle to compare the extent of insertion of the vein toward the brain. At this time, the tube was inserted at a position of 300 mm from the tip of the tube, and was gripped with the thumb and forefinger and pushed. As a result, Comparative Example 1
However, it was difficult to insert the tube at about 30 mm, and the tube finally bent so that the tube could not be completely inserted. On the other hand, in the case of Example 1, it could be smoothly inserted, and when it entered 400 mm, it was stopped and removed. According to the above results, the catheter tube-shaped member of the present invention is inserted, compared with a general catheter tube.
It can be understood that the pulling-out operation is easy and the piercing resistance is small. Therefore, even if a larger piercing resistance is applied, it is easy to operate.

Example 2 60% by weight of the powder of the thermoplastic polyimide of Example 1 and 40% by weight of the polyetheretherketone powder were mixed, and this was further mixed into a twin-screw extruder (barrel temperature 380 to 410 ° C.).
It was kneaded and pelletized. The pellets thus obtained were extruded into a tubular shape in the same manner as in Example 1. The obtained tube body had an outer diameter of 0.75 mm and a wall thickness of 130 μm.

When the tubes of Examples 1 and 2 were repeatedly bent in a loop shape and the resistances during bending were compared functionally, the resistance of Example 2 was smaller and the bending was easier. I understood. It was also found that when both hands were released in the lube state, both of them returned to their original positions in the same manner and had good elasticity.

Further, the tube was inserted from the vein of the paw of the dog in the direction of the brain in the same manner as described above, but it was inserted smoothly, and there was no resistance during withdrawal, and there was almost no difference from Example 1. .

At this time, comparing the Young's moduli of Examples 1 and 2 and Comparative Example 1, 24,000 k in order from Example 1
g / cm ² , 28,000 kg / cm ² , 3,000 k
Since it is g / cm ² , it can be said from this also that the tubular member for a catheter of the present invention has appropriate flexibility and appropriate rigidity.

Example 3 The slit width of the annular die was 0.8 mm (outer diameter 3.9 m).
m, inner diameter 2.3 mm) except that the tube body was extruded in the same manner as in Example 1. However, in this example, the discharge amount is 4
It was set to 00 g / hour, extrusion molding was started while air was being fed from the center of the die, and it was confirmed that the tube was smoothly molded and the take-up speed was adjusted to 2.68 m / min. The take-up speed was continuously accelerated from 2.68 m / min to 20 m / min for take-up. At this time, it was adjusted to reach 20 m / min in 10.6 seconds. The tube taken up by this is 2 m in length, and when the take-up speed reaches 20 m / min at about 10.6 seconds,
Next, the initial speed of 2.68 m / min was continuously decelerated for 10.6 seconds. The length of the tube collected by this was 2 m. The above is 1 cycle and total 1
The process was repeated 0 times to form 40 m, and the process was completed.

It was confirmed that the obtained tube was a tapered tube having the smallest inner and outer diameters at the extrusion position where it took 10.6 seconds and the take-up speed reached 20 m / min.
The tube thus obtained was cut into pieces each having a length of 2 m to obtain 20 tapered tube bodies. 2m
The inner and outer diameters of the tip and the proximal end of the tube body were measured, and the tip outer diameter was 0.35 mm and the inner diameter was 0.30 mm.
(The wall thickness was 50 μm), the outermost diameter of the proximal end was 0.95 mm, and the inner diameter was 0.81 mm (wall thickness 140 μm).

The tip portion of this tapered tube was more flexible than the tube of the same shape as in Example 1, and the base portion had the same hardness as in Example 1. When an insertion test was performed using a dog in the same manner as in Comparative Example 1, the insertion was easier and the extraction was easier than in Example 1.

[0035]

Since the tubular member for a catheter of the present invention is constructed as described above, it has the following effects. That is, even if the insertion distance into the body is long, the insertion can be performed very smoothly and without causing pain, and the insertion can be smoothly and swiftly performed even when withdrawn. Therefore, there is no trouble that the medical treatment stops due to bending during the insertion or withdrawal operation.

Further, according to the present invention, it is possible to gradually reduce the wall thickness of the tube from the base end portion to the tip end portion of the tube body, and to obtain a tube having a tapered outer diameter. As a result, the insertion into the body becomes smoother, and pain and discomfort are further reduced. In particular, the moderate flexibility of the tip portion has a great effect of reducing pain. It should be noted that it is generally felt that the discomfort is felt when the position of the tip portion is changed in the body, but in the present invention, such discomfort is not felt so much due to the appropriate flexibility of the tip portion.

Further, according to the present invention, since the diameter of the entire tube body can be made small and the inner diameter can be made large, it is possible to inject the liquid into the body and, conversely, to discharge secretions, blood and the like out of the body,
Suction is completed more quickly and in a shorter time. That is, in the present invention, by making the wall thickness extremely thin, the inner diameter can be increased as described above, and therefore, appropriate strength and rigidity can be maintained. Therefore, by adjusting the wall thickness and the rigidity, it is possible to obtain special effects such as obtaining various types of tubular members for catheters, and it can be effectively used not only for humans but also for other animals. Further, the present invention provides an illumination fiber for internal vision, an image guide,
It is also conceivable that it can be used as a flash hole or the like, or as an appropriate industrial use.

Claims (4)

[Claims] 1. A tubular member for a catheter comprising a seamless tubular body containing a thermoplastic polyimide resin as a main component. 2. Thermoplastic polyimide resin 55-95% by weight
And polyether ether ketone resin 45 to 55% by weight
A tubular member for a catheter, which comprises a seamless tubular body containing. 3. The tubular member for a catheter according to claim 1, wherein the tubular body has a tapered shape such that the tip end becomes thin toward at least the distal end portion. 4. The Young's modulus of the tube body is 10,000 to 5
The tubular member for a catheter according to any one of claims 1 to 3, which is in a range of 50,000 kg / cm ² .