JP2000024115A - Inner layer ptfe composite catheter tube and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inner layer polytetrafluoroethylene(PTFE) composite catheter tube which does not give rise to the disturbance of blade layers in spite of the conduction of extrusion coating work of an outer coating layer on a PTFE tube with the blade layers, allows the powerful adhesion of three layers, namely the PTFE tube, the blade layers and the outer coating layer, is eventually wide in the bore, is excellent in lubricity, is small in outside diameter and is excellent in operability and the process for producing the same. SOLUTION: This inner layer PTFE composite catheter tube is constituted by coating the surface of the PTFE resin tube layer 1 of the inner layer with the outer coating layer 4 directly or via the blade layers. The catheter tube is formed by disposing an intermediate resin layer 2 having small hardness between the inner layer PTFE tube layer 1 and the outer coating layer 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to an inner layer PTFE composite catheter tube and a method for producing the same.

[0002]

2. Description of the Related Art Catheters are widely used as medical devices for directly examining the trachea, stomach, intestine and the like. More recently,
Catheters are also being used as therapeutic devices without surgery.

[0003] The catheter here comprises a catheter tube and an operation section. The outer periphery or the intermediate layer of the catheter tube is provided with a spirally wound blade layer or a braided blade layer of a metal wire or a non-metallic striatum in order to improve operability.

[0004] In such a catheter tube used as a medical examination and treatment device, a drug and a small treatment device come and go in the tube. For this reason, in a catheter tube used also as a treatment device, it is required that the inner diameter of the tube be as large as possible and that the inner layer has as good lubricity as possible.

Conventionally, a catheter tube having a good lubricity in the inner layer is made of a fluororesin having good lubricity in the inner layer, for example, a polytetrafluoroethylene resin (hereinafter referred to as PTFE), and a mechanical property and a terminal workability are formed in the outer coating layer. A composite plastic catheter tube made of a polyamide resin, a polyamide elastomer, a polyurethane resin, a polyurethane elastomer, or the like, which has excellent properties, is used.

In a composite plastic catheter tube in which the inner layer is made of PTFE and the outer layer is made of polyamide resin, polyamide elastomer, polyurethane resin, polyurethane elastomer, etc., the outer diameter is required to be small, which is a unique requirement of the catheter tube. There is a demand that the inner diameter be made as wide as possible from the viewpoint of the penetration of the micro-therapeutic instrument inserted through the tube. Therefore, the inner layer PTF
The E layer is required to be extremely thin.

[0007]

However, if the inner layer is P
In a composite plastic catheter tube in which TFE and the outer layer are made of polyamide resin or polyurethane resin, PTFE is essentially non-adhesive and non-adhesive and has a low coefficient of friction. there were.

That is, when the blade layer is placed on the PTFE tube and the outer coating layer is extruded and coated on the upper layer of the blade layer, the pressure of the outer coating layer causes the blade layer to slide around the PTFE tube, and as a result, the blade layer slides over the PTFE tube. There was a disadvantage that the layers were greatly disturbed.

Further, since the PTFE tube does not adhere to the extruded outer layer coating layer, the obtained inner layer PT
The FE composite catheter tube has a problem that the outer coating layer is easily peeled off.

Conventionally, the following countermeasures have been taken against them.

This method increases the blade tension during blade operation, and
Embed it on the PTFE tube surface.

[0012] The adhesive treatment to the blade this method, an adhesive is applied onto the blade surface during blade operation, thereby bonding the blade and PTFE tube surface.

However, these improvements have the following disadvantages.

Reinforcement of blade tension If the tension of the blade is increased by this method, the workability deteriorates and the disconnection of the blade frequently occurs.

Further, as a result of embedding the blade on the ultra-thin walled PTFE tube, unevenness of the PTFE tube may occur, or a cut of the PTFE tube may occur.
In severe cases, the PTFE tube pieces may peel off.

The adhesive treatment to the blade in this way, the results of applying an adhesive onto the surface of the blade, there is difficulty working steps increases, and aging of the safety issues and the adhesive on the human body of applied adhesive There are difficulties such as deterioration.

The present invention has been made in view of such a point, and an object of the present invention is to solve the above-mentioned disadvantages of the prior art, and to extrude and coat an outer coating layer on a PTFE tube with a blade layer. The PTFE tube, the blade layer, and the outer coating layer can be strongly adhered to each other without causing disturbance of the blade layer, so that the inner diameter is wide and excellent in lubricity, and the outer diameter is small, and the operability is further improved. Is to provide an inner layer PTFE composite catheter tube having excellent properties and a method for producing the same.

[0018]

The gist of the present invention lies in the following three points.

(1) An inner layer PTFE composite catheter tube in which an outer layer is coated directly or via a blade layer on the inner layer polytetrafluoroethylene resin tube layer, wherein the inner layer polytetrafluoroethylene resin tube layer and the outer layer An inner layer PTFE comprising an intermediate resin layer having low hardness provided between the inner layer PTFE and the coating layer.
Composite catheter tube.

(2) An inner-layer PTFE composite catheter tube characterized in that a low-hardness resin is extruded and coated on a polytetrafluoroethylene resin tube, and then an outer coating layer is extruded and coated on the low-hardness resin layer. Production method.

(3) A low-hardness resin is extruded and coated on the polytetrafluoroethylene resin tube, and then a braided braid layer is embedded in the low-hardness resin layer so that a part or the whole of the braided wire is buried. A method for manufacturing an inner-layer PTFE composite catheter tube, comprising: extruding and coating an outer coating layer on the braided braid layer after the provision.

That is, in the present invention, by disposing an intermediate resin layer having low hardness on the inner layer polytetrafluoroethylene resin tube by extrusion, the disturbance of the blade layer is prevented and the inner layer polytetrafluoroethylene resin tube, the blade layer, the outer layer The purpose of the present invention is to firmly adhere the three members of the coating layer.

The low hardness intermediate resin is excellent in softness, flexibility, adhesiveness and the like because of its low hardness.

[0024]

Next, an embodiment of the inner layer PTFE composite catheter tube of the present invention and a method for producing the same will be described.

In the present invention, as the intermediate resin layer, EV
It is preferably one type selected from A resin, EEA resin, and EMA resin.

In this case, the intermediate resin layer is preferably an EVA resin, an EEA resin or an EMA resin containing at least 25 mol% of an acrylate group.

Further, in the EVA resin used as the intermediate resin layer, the higher the VA amount, the lower the hardness, the softer,
It is sticky.

[0028]

Next, examples of the inner layer PTFE composite catheter tube of the present invention and a method for producing the same will be described together with comparative examples.

(Example 1) First, the inner diameter φ0.
A PTFE tube having a thickness of 8 mm and a thickness of 30 μm was manufactured.

Next, on the manufactured PTFE tube, as an intermediate layer, 40 mol% of ethylene acetate was used.
Vinyl acetate resin (hereinafter referred to as EVA resin) with a thickness of 50
It was extruded and coated to a thickness of μm.

Next, the inner layer PTFE composite catheter tube of Example 1 was obtained by extruding and coating a polyamide resin as an outer layer coating material so as to have a finished outer diameter of φ1.2 mm on the EVA resin layer.

FIG. 1 shows a sectional view of the inner layer PTFE composite catheter tube of Example 1 thus obtained.

In FIG. 1, 1 is an inner layer PTFE tube,
2 is an intermediate EVA resin layer and 4 is an outer polyamide resin layer.

(Embodiment 2) First, the inner diameter φ0.
A PTFE tube having a thickness of 8 mm and a thickness of 30 μm was manufactured.

Next, an EVA resin containing 40% by mole of vinyl acetate was extruded as an intermediate layer onto the manufactured PTFE tube so as to have a thickness of 50 μm.

Next, on the EVA resin layer, an outer diameter φ4
A braided blade layer having a pitch of 2.5 mm was provided using 16 SUS wires of 0 μm.

Next, the inner layer PTFE composite catheter tube of Example 2 was obtained by extruding and coating a polyamide resin as an outer layer coating material so as to have a finished outer diameter of φ1.2 mm on the braided blade layer.

FIG. 2 is a cross-sectional view of the inner-layer PTFE composite catheter tube of Example 2 thus obtained.

In FIG. 2, 1 is an inner layer PTFE tube,
2 is an intermediate EVA resin layer, 3 is an intermediate braided blade layer, and 4 is an outer polyamide resin layer.

Comparative Example 1 First, the inner diameter φ0.
A PTFE tube having a thickness of 8 mm and a thickness of 30 μm was manufactured.

Next, the resulting PTFE tube is extruded and coated with a polyamide resin as an outer layer coating material so as to have a finished outer diameter of 1.2 mm.
An inner layer PTFE composite catheter tube of Comparative Example 1 was obtained.

FIG. 3 shows a sectional view of the inner layer PTFE composite catheter tube of Comparative Example 1 thus obtained.

In FIG. 3, 1 is an inner layer PTFE tube,
4 is an outer polyamide resin layer. (Comparative Example 2) First, a PTFE tube having an inner diameter of 0.8 mm and a thickness of 30 µm was manufactured by a standard method.

Next, a braided blade layer having a pitch of 2.5 mm was provided on the manufactured PTFE tube using 16 SUS wires having an outer diameter of 40 μm.

Next, the inner layer PTFE composite catheter tube of Comparative Example 2 was obtained by extruding and coating a polyamide resin as an outer layer coating material to a finished outer diameter of φ1.2 mm on the braided blade layer.

FIG. 4 is a cross-sectional view of the inner-layer PTFE composite catheter tube of Comparative Example 2 thus obtained.

In FIG. 4, 1 is an inner layer PTFE tube,
Reference numeral 3 denotes an intermediate braided blade layer, and reference numeral 4 denotes an outer polyamide resin layer.

(Characteristic Test Method) Next, a characteristic test was performed on the inner-layer PTFE composite catheter tubes of Examples 1 and 2 and Comparative Examples 1 and 2 thus obtained.

A. When the orderly outer layer of the blade layer was extruded and coated, the blade layer having no disturbance was indicated by ○, and the disordered blade layer was indicated by x.

B. Flexibility test (adhesion between inner and outer layers)
Property ) The distal ends of the inner layer PTFE composite catheter tubes of Examples 1 and 2 and Comparative Examples 1 and 2 were bent at 90 degrees until the inner layer and the outer layer were separated.

(Characteristic test results) Table 1 shows the characteristic test results.

[0052]

[Table 1]

As can be seen from Table 1, the inner layer PTFE composite catheter tube of Comparative Example 1 having a structure without the blade layer does not naturally cause disturbance of the blade layer, but in the bending test, the inner layer and the outer layer are bent 36 times. And peeled off.

The inner layer P of Comparative Example 2 having a structure having a blade layer
In the TFE composite catheter tube, the turbulence of the blade layer occurred, and in the bending test, the inner layer and the outer layer peeled off at 42 bends.

On the other hand, the inner layer PTFE composite catheter tube of Example 1 having the structure without the blade layer showed an excellent result of 520 flexural bends.

Further, the inner layer PTFE composite catheter tube of Example 2 having the structure having the blade layer showed excellent results in that the blade layer was not disturbed and the bending resistance was 650 times.

[0057]

According to the inner layer PTFE composite catheter tube of the present invention and the method for producing the same, the PTFE with a blade layer is provided.
Extrusion of the outer layer coating material onto the E tube does not cause disturbance of the blade layer even when the coating operation is performed, and the PTFE tube, the blade layer, and the outer layer coating material can be strongly adhered to each other, resulting in a wide inner diameter and lubrication. The present invention can provide an inner layer PTFE composite catheter tube having excellent operability, a small outer diameter, and excellent operability, and is industrially useful.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of an inner-layer PTFE composite catheter tube according to Example 1 of the present invention.

FIG. 2 is a cross-sectional view of an inner-layer PTFE composite catheter tube according to a second embodiment of the present invention.

FIG. 3 is a cross-sectional view of the inner layer PTFE composite catheter tube of Comparative Example 1.

FIG. 4 shows a cross-sectional view of the inner layer PTFE composite catheter tube of Comparative Example 2.

[Explanation of symbols]

 Reference Signs List 1 inner layer PTFE tube 2 intermediate EVA resin layer 3 intermediate braided blade layer 4 outer layer polyamide resin layer

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Toshiharu Goto 5-1-1, Hidaka-cho, Hitachi City, Ibaraki Prefecture F-Term in Power Systems Research Laboratories, Hitachi Cable, Ltd. 4C081 AC08 BB04 BB05 BB07 BC02 CA052 CA082 CA131 CA131 CA212 CA232 CB052 DA03 DC03 DC04 DC05 DC06 EA02 EA03

Claims (6)

[Claims] An inner PTFE composite catheter tube comprising an outer coating layer coated directly or via a blade layer on an inner polytetrafluoroethylene resin tube layer, wherein the inner polytetrafluoroethylene resin tube layer and the outer coating are provided. An inner-layer PTFE composite catheter tube comprising an intermediate resin layer having a low hardness between the inner layer and the inner layer. 2. The inner layer PTFE composite catheter tube according to claim 1, wherein a part or the whole of the blade layer is embedded in the intermediate resin layer. 3. An intermediate resin layer comprising an EVA resin, an EEA resin,
The inner layer PTFE composite catheter tube according to claim 1, wherein the tube is one selected from EMA resin. 4. The method according to claim 1, wherein the intermediate resin layer has an acrylate group content of 25 mol%.
The inner layer PTFE composite catheter tube according to claim 1, wherein the tube is an EVA resin, an EEA resin, or an EMA resin contained above. 5. A method for manufacturing an inner-layer PTFE composite catheter tube, comprising extruding a low-hardness resin onto a polytetrafluoroethylene resin tube, and thereafter extruding and coating an outer coating layer on the low-hardness resin layer. Method. 6. A low-hardness resin is extruded and coated on a polytetrafluoroethylene resin tube, and then a braided blade layer is provided in the low-hardness resin layer so that a part or the whole of a braided wire is buried. And then extruding and coating an outer coating layer on the braided braid layer.