JP2000262625A - Catheter tube and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to form a flexible front end of a catheter tube consisting of an inner layer resin layer, a reinforcing layer consisting of metallic strands and an outer layer resin layer and to improve its operability by making the metallic strands constituting the reinforcing layer at the front end discontinuous and forming these strands as the flexible front end. SOLUTION: At the time of production of the catheter tube, the inner layer resin layer is formed on a metallic core wire and a reinforcing layer structure consisting of reinforcing bodies is formed by using the metallic strands on the resulted inner layer coating metallic wire body. The reinforcing bodies are fixed to the inner layer resin layer by an impregnating and baking treatment using a PTFE dispersion coating material at need. Next, the section corresponding to the front end of the inner layer coating metallic wire body with the reinforcing bodies is irradiated with a laser, by which the metallic strands are cut at desired intervals. The outer layer resin layer is formed on the resulted inner layer coating metallic wire body with the laser processed reinforcing bodies. The front end section and main body section of the long-sized body having the repetition of the resulted front end sections and main body sections are cut as a set. The metallic core wire is drawn from this cut body, by which the catheter tube is completed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a catheter tube used in a medical institution such as a hospital and a method for manufacturing the same.

[0002]

2. Description of the Related Art In a medical institution such as a hospital, a drug solution or a contrast agent is injected into a predetermined site in a living body of a patient from the outside.
2. Description of the Related Art A flexible tube-shaped medical device called a catheter is used to discharge a body fluid or the like in a living body. Generally, since this catheter is designed to be inserted into the living body using thin blood vessels and ureters,
Especially at the time of insertion, in addition to the demand for high operability and safety to accurately reach a predetermined location in the living body without damaging the blood vessel wall and living organs along the way, injection of drug solutions and contrast agents, other When inserting a catheter, it is required that smooth injection and insertion be possible.

[0003] Therefore, this catheter has a bendable and highly resilient tip for inserting a blood vessel and a living organ without damaging it, and is connected to the tip so that the tip reaches a predetermined location without fail. And a torque transmitting unit (main body) for maintaining torque transmission. In addition, in order to enhance torque transmission, the torque transmission unit (main body) is provided with a reinforcing layer using a metal element wire on the inner tube,
It is made of hard material. The tip is made of a soft material to make it easy to bend and has high elasticity, or it is constructed by connecting a tube without a reinforcing layer containing a metal wire as a tip to the main body (torque transmitting part). Or Further, a tube in which a lubrication (low friction resistance) layer is formed on the inner surface of the inner tube has been developed. As a method for providing a lubricating layer on the inner surface, a method of forming a PTFE layer of a fluororesin or a method of forming a lubricating coating film by coating a silicone-based paint on the inner surface are known.

[0004] As a conventional method for manufacturing a catheter, an inner resin layer is first provided on a round wire (core wire), and the outer periphery of an inner tube body made of a flexible plastic into which the obtained round wire is inserted is provided with a corrosion resistant material. After applying a braid made of a metal wire with a braiding machine, subsequently, the braided inner tube body is passed through a heated mold, and the braid is embedded in the inner tube body to form a reinforcing layer, and the surrounding layer is formed. A torque transmission unit provided with a reinforcing layer is configured. Next, the reinforcing layer located at the tip portion of the torque transmitting portion, that is, the metal wire of the metal wire braid is removed by an electrochemical, chemical or mechanical metal removal method or the like, so that the tip portion rich in elasticity is removed. After forming the outer layer, the outer layer of the inner tube body is coated with several kinds of plastics in an extrusion step so as to cover the reinforcing layer to form an outer resin layer, and then a torque transmitting portion and a tip end portion are formed. While cutting to the length of the actual catheter,
There is known a method for producing a catheter in which the above-mentioned round wire is drawn and then pulled out from the inner tube.

[0005]

By the way, as described above, the metal wire braid (reinforcing layer) is not provided at the tip, and the metal wire braid (reinforcing layer) is provided at the torque transmitting portion (main body). In order to obtain a catheter structure having a metal wire braid, the metal wire of the metal wire braid at the distal end portion is removed by an electrochemical method or the like, or another tube body not incorporating the metal wire braid is used. It is necessary to connect the tip of the torque transmitting portion with a fusion connection or an adhesive, but any of these methods has a difficult problem.

That is, in order to remove the braid in the coating layer, an apparatus and a process for removing the braid are required, and the production efficiency is low. When the braid is locally removed before the outer resin layer is applied, particularly when the braid is applied on the PTFE resin, the braid and the PTFE do not adhere to each other. There is a problem that the braid peels off or floats, which causes a problem that the position of the braid shifts when the outer periphery is coated with the outer resin layer.

[0007] In the method of fusion bonding, the inside diameter and the outside diameter may be changed at those connection portions. Furthermore, in the connection using an adhesive, since the bonding area is small, it is difficult to obtain a stable strength, and there is a problem that the tip portion bonded during the operation is missing in the living body. Furthermore, it is difficult to seamlessly connect tubes having a PTFE layer in the inner layer, and there is a problem that the tube is cut or peeled off at a connection portion of the PTFE. Is extremely difficult.

In the method of forming a PTFE layer on the inner surface or coating the inner surface with a paint to form a lubricating layer on the inner surface of the inner tube, PTFE is used to adhere to the outer layer material or blade when the blade is applied. (Adhesion) is not obtained, and peeling is apt to occur, and there is a problem that stability cannot be obtained in terms of operability such as torque transmission. In the method of coating with paint, another catheter or guide wire is used. There is a problem that the insert is easily shaved by insertion and the insertability is easily changed during surgery.

Furthermore, if the braid at the distal end is completely removed in order to obtain the flexibility at the distal end, it becomes difficult to stably secure the lumen shape of the catheter tube in the meandering blood vessel. There is.

Accordingly, the present invention has been devised to effectively solve such a problem. That is, an object of the present invention is to provide a catheter tube having a reinforcing layer including a metal wire between an inner resin layer and an outer resin layer, a torque transmitting section in which the metal wires in the reinforcing layer are continuous, and a reinforcing layer. It enables a catheter tube having a flexible distal end where the metal wire is discontinuous, and the metal wire in the reinforcing layer is braided or coiled, and the inner layer is made of a fluororesin layer and its outer periphery The metal wire of the reinforcing layer applied to the inner layer is impregnated with a polytetrafluoroethylene resin-dispersed paint, and baking enables the catheter tube to be fixed to the inner layer resin layer, thereby changing the flexibility in the distal direction. An object of the present invention is to provide a novel catheter tube having excellent operability and having the above.

[0011]

According to the present invention, there is provided a catheter tube comprising an inner resin layer, a reinforcing layer made of a metal wire formed on the inner resin layer, and an outer resin layer formed on the reinforcing layer. In the catheter tube having a main body functioning as a torque transmitting portion and a distal end portion for continuous insertion into the main body, a metal strand constituting the reinforcing layer in the main body is continuous, The metal wires constituting the reinforcing layer at the distal end are discontinuous so that a flexible distal end is formed.

In the catheter tube according to the present invention, the metal wire included in the reinforcing layer may be a braided or coiled metal wire.

Further, in the catheter tube according to the present invention, the inner resin layer is made of a fluororesin layer, and the metal wire in the reinforcing layer formed on the inner resin layer is made of a polytetrafluoroethylene resin-dispersed paint. Can be immobilized on the inner resin layer by impregnation and baking.

According to a method of manufacturing a catheter tube according to the present invention, the inner resin layer is formed by a method of manufacturing a catheter tube having a main body functioning as a torque transmitting portion and a distal end for continuous insertion into the main body. Performing a step of forming a reinforcing layer made of a braided or coiled metal element wire on the inner layer resin layer, cutting the metal element wire by irradiating a laser beam to a portion corresponding to the tip end, and discontinuously. And a step of forming an outer resin layer on the reinforcing layer.

In the method for manufacturing a catheter tube according to the present invention, the resin used in the step of forming the inner layer resin layer is a fluororesin, and the step of forming the reinforcing layer includes the step of forming the metal wire by polytetrafluoroethylene. The method may include a step of impregnating and baking with a fluoroethylene resin-dispersed coating material and fixing it to the inner resin layer.

Preferred examples of the resin constituting the inner resin layer in the present invention include a fluorine-based resin. Examples of the fluorine-based resin include, but are not particularly limited to, polytetrafluoroethylene (PTFE) and polyethylene. Tetrafluoroethylene (ETFE), perfluoroalkoxy fluororesin (PFA), ethylene tetrafluoride hexafluoropropylene copolymer (FEP), vinylidene fluoride (P
A known fluororesin such as VDF) can be used.
Particularly preferred are PTFE, ETFE and PFA.

In the present invention, the reason that the above-mentioned fluororesin is suitable as a constituent material of the inner resin layer is that it is suitable for forming a flexible front end in which the metal wires in the reinforcing layer are discontinuous. This is because it is suitable for performing a laser cutting method, which is a simple method. That is, after forming a reinforcing layer including a continuous metal element wire similar to that of the main body (torque transmitting portion) at the tip corresponding portion, a wavelength of 1.06 μm is applied to the tip corresponding portion.
m, the metal wire is cut at an arbitrary interval by irradiating a laser beam of m to form a tip portion including the cut metal wire which is discontinuous, and the fluororesin has a wavelength of 1.06 μm. This is because the laser light is very easily transmitted. In this case, it is desirable that the fluororesin is not colored. This is to facilitate transmission of the 1.06 μm laser light, and to further eliminate the influence of the absorption of the laser light on the resin.

In the reinforcing layer of the present invention, the material of the metal wire for reinforcement is not particularly limited, but stainless steel wire, platinum wire, gold wire and the like can be used. The wire may be a round wire or a flat wire. Furthermore, it is preferable that the metal wires in the reinforcing layer be braided or coiled, because in addition to being effective in preventing the catheter tube from being crushed, continuous production is also necessary. In addition to this, continuous processing is easy.

In the catheter tube of the present invention, the metal strands in the reinforcing layer of the torque transmitting portion (main body portion) are continuous because when the torque transmitting portion is rotated, the rotation is improved from the distal end to the distal end. To convey. Further, the reason why the metal wires in the reinforcing layer at the flexible distal end are discontinuous is that the distal end portion is easily bent when advancing inside the meandering blood vessel so as to enhance the insertability, and the blood vessel shape is also increased. This can prevent the blood vessel from being damaged by following, and make it easier to process the tip into a shape suitable for the blood vessel shape.

In the catheter tube of the present invention, a reinforcing layer made of a metal wire (reinforcing body) is impregnated with a polytetrafluoroethylene (PTFE) resin-dispersed coating material and baked to form a braided inner resin layer. Alternatively, the coil or the like is fixed by fixing a braided metal wire to the inner fluororesin layer so that peeling between the fluororesin layer and the braid can be prevented. A part of a metal wire such as a braid is exposed on the surface due to wettability with the dispersion type PTFE, so that the braid and a thermo-flexible resin as an outer layer resin material to be coated thereon are easily adhered to each other, and separation from the outer layer is also prevented. This is because you can do it. Furthermore, since the braid or the like is exposed, it can be easily cut by a laser. Further, since the braid is fixed to the inner fluororesin layer, peeling of the braid or the like due to cutting at an arbitrary interval can be prevented.

The resin constituting the outer resin layer in the present invention is not particularly limited, but examples thereof include resins of polyurethane type, polyamide type, polyimide type, polyethylene type, polyvinyl chloride type and fluororesin type. Can be If necessary, barium sulfate, bismuth oxide, tungsten carbide, or the like is added to the resin for the outer resin layer as a contrast agent.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION One embodiment of a catheter tube according to the present invention is a braided or coiled reinforcement formed by forming an inner resin layer on a metal core wire and using a metal wire on the obtained inner coated metal wire. A reinforcing layer structure made of a metal body is formed, and if necessary, impregnated with a PTFE-dispersed paint and baked to fix the metal wire reinforcing body to the inner layer resin layer, and obtain the obtained inner layer-coated metal wire with a reinforcing body. A laser beam is applied to a portion corresponding to the tip of the body to cut a braided or coiled metal element wire at a desired interval, and an outer resin layer is formed on the obtained inner layer coated metal wire with a laser-processed reinforcing body. The repeated elongated body of the tip portion and the main body portion is cut by setting the tip portion and the main body portion as a set, and a metal core wire is pulled out from the obtained cut body, and the integrated tip portion and the main body portion are formed. Catheter tube It can be obtained by.

As the metal core wire, various metal conductors can be used, but a metal wire conductor plated with gold or silver is preferable. Gold or silver wavelength 1.06μm
This is because most of the laser light is reflected, so that the influence of the laser light transmitted through the resin on the core conductor can be eliminated.

As will be understood from the above description,
A laser having a wavelength of 1.06 μm is effective as a laser constituting a reinforcing layer containing discontinuous metal wires by cutting the metal wire reinforcement at the tip end at a desired interval. An example of using a laser is shown.

As described above, the inner resin layer made of a fluororesin and the reinforcing member made of a braided or coiled metal wire applied thereon are impregnated with a polytetrafluoroethylene resin dispersed paint and baked. By performing the fixing, more stable operability can be obtained.

[0026]

EXAMPLES Catheter tubes were prepared according to Examples and Comparative Examples, and their performance was compared and evaluated.

(Example) After coating and baking a water-dispersed PTFE dispersion on a silver-plated soft copper wire having an outer diameter of 1.40 mm to a thickness of 0.03 mm, a SUS element having a diameter of 0.03 mm was used as a metal reinforcing layer. Braid processing of 16 wires (pitch 3.3), and water-dispersed PTFE from the braid
200 m core with dispersion coated and baked
Produced. Next, using a twin head Q-switched YAG laser (manufactured by NEC; SL475H / HF), 1500 mm
A polyamide elastomer (PEBAX 633) is provided on a core obtained by cutting the metal reinforcing layer at intervals of 10 mm between 200 mm every time.
3, 0.10 m of contrast agent bismuth oxide 30 wt% added)
The coated wire obtained by coating the metal tube is cut into a set of a torque transmitting portion having a continuous metal reinforcement layer and a flexible distal end having a discontinuous metal reinforcement layer, and the core wire is removed. A flexible part length of 150 mm and a torque part length of 1500 mm) were obtained.

(Comparative Example) An aqueous dispersion type PTFE dispersion was repeatedly applied and baked on a silver-plated soft copper wire having an outer diameter of 1.40 mm to a thickness of 0.03 mm, and then a SUS element having a diameter of 0.03 mm was used as a metal reinforcing layer. Braid processing of 16 wires (pitch 3.3), and water-dispersed PTFE from the braid
200 m core with dispersion coated and baked
Produced. Next, a polyamide elastomer (P
The coated wire obtained by coating 0.10 mm with EBAX6333 (contrast agent bismuth oxide 30 wt%) was cut at a predetermined length, and the core wire was removed to obtain a catheter tube in which the metal reinforcing layer was continuous over the entire length.

(Test 1: Tip Steam Formability Test) 90
The tube was exposed to steam at about 100 ° C. for 20 seconds while the tube was bent at 90 ° by inserting a mandrel with an angle of ° into the tip of the tube, and after cooling, the mandrel was removed and the angle of the tube was measured. .

(Test 2: Kink resistance test) A sample tube having a length of 1 m was looped, one end was fixed, and the other was gradually pulled to shrink the loop. The length of the tube at the loop was measured.

(Test 3: Catheter Insertion Test) Using a blood vessel simulating device for evaluating catheter insertability (using a PVC tube having an inner diameter of 2 mmΦ as a simulated blood vessel and injecting physiological saline into the tube), the insertion length of the tube was determined. It was measured. The blood vessel simulating device is a PVC tube having a total length of 1500 mm, bending R20 mm: 2 places, 10 mm: 5 places, 5 places.
mm: What set three places was used.

Table 1 shows the evaluation results.

[0033]

[Table 1]

As shown in Table 1, a tip portion and a main body portion (torque transmitting portion) are provided, an inner resin layer, a reinforcing layer comprising a metal wire reinforcing body on the inner resin layer, and a reinforcing layer on the reinforcing layer. In a catheter tube having an outer resin layer, the inner layer is made of a fluororesin layer, the reinforcing layer in the main body is made of a continuous metal wire braid or coil reinforcement, and the reinforcing layer at the distal end is made of a metal wire braid or coil reinforcement. By reinforcing the metal wire reinforcement with a laser-cut discontinuous metal wire, and impregnating the metal wire reinforcement with a polytetrafluoroethylene resin-dispersed paint, baking and fixing the inner layer resin layer. It is possible to obtain a new catheter tube which is excellent in kink resistance and simulated blood vessel insertion property after forming the tip steam which has flexibility in the tip direction and has excellent operability. I was able.

[0035]

In summary, according to the present invention, the main body portion (torque transmitting portion) is provided with a reinforcing layer including a continuous metal wire, and the distal end portion (insertion portion) is provided with a discontinuous metal wire. The catheter tube is configured so as to be provided with the reinforcing layer including the reinforcing layer, and it is possible to manufacture a catheter tube having excellent moldability and operability.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hiroyuki Ito 5-1-1 Hidakacho, Hitachi City, Ibaraki Prefecture Inside the Hidaka Factory, Hitachi Cable, Ltd. (72) Inventor Masao Shirachi 5 Hidakacho, Hitachi City, Ibaraki Prefecture No. 1-1, Hidaka Plant, Hitachi Cable, Ltd.

Claims (5)

[Claims] A main body functioning as a torque transmitting unit, comprising an inner resin layer, a reinforcing layer made of a metal strand formed on the inner resin layer, and an outer resin layer formed on the reinforcing layer; In a catheter tube having a distal end for continuous insertion into the main body, the reinforcing layer in the main body is constituted by a continuous metal wire,
A catheter tube characterized in that the reinforcing layer at the distal end is formed by a discontinuous metal wire. 2. The catheter tube according to claim 1, wherein the metal wire included in the reinforcing layer is a braided or coiled metal wire. 3. The method according to claim 1, wherein the inner resin layer is made of a fluororesin layer, and the metal wires in the reinforcing layer formed on the inner resin layer are impregnated with a polytetrafluoroethylene resin dispersed paint and baked. 3. The fixing device according to claim 1, wherein the fixing member is fixed to the inner resin layer.
The catheter tube according to any one of the preceding claims. 4. A method of manufacturing a catheter tube having a main body functioning as a torque transmitting section and a distal end for continuous insertion into the main body, wherein an inner resin layer is formed on the inner resin layer. A step of forming a reinforcing layer made of a braided or coil-shaped metal element wire, a step of cutting the metal element wire by applying a laser beam to a portion corresponding to the tip to make the metal wire discontinuous, and A method for producing a catheter tube, comprising a step of forming an outer resin layer. 5. The resin used in the step of forming the inner layer resin layer is a fluororesin, and the step of forming the reinforcing layer includes impregnating and baking the metal strand with a polytetrafluoroethylene resin dispersion paint. The method for producing a catheter tube according to claim 4, further comprising a step of fixing the inner tube to the inner resin layer.