JP2002113092A - Manufacturing method for medical instrument and medical instrument - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method for a medical instrument capable of freely controlling various characteristics such as elasticity, rigidity, hardness, electric conductivity, and ionization tendency. SOLUTION: This manufacturing method has a process for forming a metal thin film 60 having the thickness of 50 μm or below by sputtering on the surface of a core member 100 or on an intermediate layer forming the medical instrument.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for manufacturing a medical device and a medical device.

[0002]

2. Description of the Related Art Resin tubes are generally used for medical instruments such as medical catheters, but for medical use, thinner tubes are required.
For this reason, there is a problem that the strength of the tube in the axial direction is weakened and the push-in characteristics (pushability) are deteriorated. Therefore, it has been proposed that the tube forming the catheter is formed of a metal tube. However, a normal metal tube lacks flexibility, and it is difficult to insert the tube well into a tortuous portion such as a blood vessel. It is.

Therefore, it has been proposed that a tube constituting a catheter or the like be formed of a superelastic alloy such as a nickel-titanium alloy.

[0004] As a method of manufacturing a tube made of a metal such as a nickel-titanium alloy, a method of bending a thin metal plate into a tube shape, seam-welding the joint portion, and stretching the metal plate has been conventionally proposed. However, in this method, there is a limit in reducing the thickness of the tube, and the strength of the seam welded portion becomes a problem, and the tube has a problem of being weak against bending.

It is also known to manufacture metal tubes by machining such as extrusion and drawing. However, even with this method, there is a limit in reducing the thickness of the tube.

Although a technique for forming a metal thin film on a metal surface by using an electrolytic plating method is known, in the electrolytic plating method, for example, a metal thin film is formed on a surface of a non-conductive material such as a synthetic resin. I can't. Although an electroless plating method capable of forming a metal thin film on the surface of a material other than metal is also known, the types of metal that can be used as the metal thin film are limited, and a superelastic metal thin film is formed. I can't.

[0007]

DISCLOSURE OF THE INVENTION The present invention has been made in view of such circumstances, and has been made in consideration of elasticity, rigidity, hardness, electric conductivity, and the like.
It is a first object of the present invention to provide a method for manufacturing a medical device capable of freely controlling various properties such as ionization tendency. A second object of the present invention is to provide a medical device which can easily follow a strongly bent portion of a biological organ such as a blood vessel and is deformable so as to be able to be restored, and which has excellent pushing characteristics.

[0008]

In order to achieve the first object, a method of manufacturing a medical device according to the present invention comprises forming a metal thin film on a surface or an intermediate layer of a member constituting the medical device by sputtering. The step of performing The metal thin film may be formed on the surface of the member or at least a part of the intermediate layer, and need not necessarily be formed on the entire circumference.

The member constituting the medical device is not particularly limited, but is, for example, any one of synthetic resin, metal and ceramics.

In order to achieve the second object, the medical device according to the present invention has a superelastic metal thin film having a thickness of 50 μm or less. In the present invention, the superelastic metal is not particularly limited. For example, nickel-titanium, iron-
Manganese-silicon, copper-aluminum-nickel,
Examples thereof include an amorphous metal type. In the present invention, the term “superelasticity” refers to a material having a large recoverable elastic strain range of, for example, 1% to 10%, and includes pseudoelasticity causing twinning deformation and large elasticity of amorphous. Shall be considered. In general, a superelastic metal has an elastic modulus in a superelastic region smaller than that of iron or stainless steel, and is excellent in flexibility.

[0011]

According to the method for manufacturing a medical device according to the present invention, any combination of composite structures such as a composite structure of a thin film metal and a metal, a composite structure of a thin film metal and a ceramic, and a composite structure of a thin film metal and a synthetic resin can be used. Medical devices consisting of structures can be manufactured. Therefore, according to the manufacturing method of the present invention, a medical device capable of freely controlling various properties such as elasticity, rigidity, hardness, electric conductivity, and ionization tendency can be manufactured.

Since the medical device according to the present invention has a superelastic metal film having a thickness of 50 μm or less, it has excellent elasticity, and easily deforms so as to be able to follow a strongly bent portion and be restored. Further, the operating force at the proximal end of the medical device is transmitted well to the distal end, and the push-in characteristic is excellent.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on embodiments shown in the drawings. 1A to 1C are cross-sectional views of a main part showing a method for manufacturing a medical device according to an embodiment of the present invention. FIG. 2 is a magnetron used in the method for manufacturing a medical device according to an embodiment of the present invention. FIG. 3 is a schematic sectional view of a sputtering apparatus according to another example, FIG. 3 is a schematic view of a sputtering apparatus according to another example, and FIG. 5 is a medical diagram according to one embodiment of the present invention. FIG. 6 is a schematic sectional view of a guide wire, and FIG. 6 is a schematic view showing an example of use of the guide wire shown in FIG.

First Embodiment As shown in FIG. 1A, in this embodiment, a medical device 1
A metal thin film 60 having a thickness of preferably 50 μm or less is formed on the entire surface or a part of the surface of the core material 100 constituting the substrate 20 by magnetron sputtering. The core material 100 is not particularly limited, but is made of, for example, metal, ceramic, synthetic resin, or the like. The cross-sectional shape of the core material 100 is not particularly limited, and may be a circle, an ellipse, a polygon, or another shape. In this embodiment, the core member 100 is formed of a rod having a circular cross section.

The outer diameter and length of the core material 100 are appropriately determined according to the use of the medical device 120 and the like. In the present embodiment, the outer diameter of the core material 100 is 0.1 mm or less. good.

On the entire surface or a partial surface of the core material 100,
In order to form the metal thin film 60 by the magnetron sputtering method, a magnetron sputtering device 70 shown in FIG. 2 is used. In order to form the metal thin film 60 only on a part of the surface of the core material 100, magnetron sputtering may be performed after masking a part of the surface of the core material 100 with a resist film or the like.

The magnetron sputtering apparatus 70 shown in FIG. Inside the vacuum processing chamber 72, an installation table 76 on which a target 74 is set is disposed at the bottom thereof. Outside the vacuum processing chamber 72, magnetron magnets 78 and 80 for providing magnetic lines of force to the target 74 are arranged.

One end of the core member 100 is rotated by a rotation holding device 82 so that the core member 100 is rotatably disposed around the axis inside the target 74 inside the vacuum processing chamber 72. It is kept. The core material 100 is rotated by the rotation holding device 82 while magnetron sputtering is performed while rotating the core material 100 around the axis.
A metal thin film 60 is formed on the outer peripheral surface of the zero.

As the target 74, an alloy target may be used, but a plurality of single-type metal targets, each of which is different, may be used. In this embodiment, a nickel-titanium alloy target or a combination of a nickel target and a titanium target is set on the mounting table 76.

The thickness of the metal thin film 60 formed on the outer peripheral surface of the core material 100 using the magnetron sputtering apparatus 70 shown in FIG. 2 is not particularly limited.
The thickness can be reduced to about μm or less. In the present embodiment, the metal thin film 60 is made of a superelastic metal made of a nickel-titanium alloy.

The specific use of the medical device 120 of the present embodiment is not particularly limited. For example, a guide wire for guiding a balloon catheter, a snare wire, a guiding catheter, an electrode catheter, a pacing electrode, a stent, a thrombus removal basket , A puncture needle, a stapler needle (a needle of a suturing machine), a blood vessel clip, and the like.

Second Embodiment A method for manufacturing a medical device according to the present embodiment is a modification of the method for manufacturing a medical device according to the first embodiment. FIG. 3 shows a part of a sputtering apparatus used in the manufacturing method. Except for the configuration shown, it is the same as the first embodiment, and only different parts will be described.

As shown in FIG. 3, in the manufacturing method according to this embodiment, a pair of rotation-permitting seal devices 84 are provided on opposing side walls of the vacuum processing chamber 72 of the sputtering apparatus.
The core member 100 is held inside the processing chamber 72 through the sealing devices 84. The core material 100 is shown in FIG.
As shown in FIG. 7, inside the processing chamber 72, the processing chamber 72 is rotatably held by a sealing device 84, and is movable in the axial direction from right to left in FIG. The sealing device 84 is configured to be able to seal the inside of the processing chamber 72 irrespective of the rotational movement and the axial movement of the core material 100 around the axis.

The core material 100 is moved in the axial direction while being rotated inside the processing chamber 72, and magnetron sputtering similar to that in the first embodiment is performed.
The metal thin film 60 shown in FIG. 1A can be formed on the outer peripheral surface of the core material 100 continuously along the axial direction.
Other steps in the present embodiment are the same as those in the first embodiment, and a description thereof will be omitted.

Third Embodiment A method for manufacturing a medical device according to the present embodiment is a modification of the method for manufacturing a medical device according to the first embodiment. FIG. 4 shows a part of a sputtering apparatus used in the manufacturing method. Except for the configuration shown, it is the same as the first embodiment, and only different parts will be described.

As shown in FIG. 4, in the manufacturing method according to the present embodiment, a supply roll 86 for the core material 100 and a take-up roll 88 are arranged inside the vacuum processing chamber 72 of the sputtering apparatus. A part of the core material 100 to be continuously processed is positioned above the target 74 by the intermediate holding rolls 90 and 92. The supply roll 86 and the take-up roll 88 are each held by a rotation support frame 94, are rotated in opposite directions by a drive motor 96, respectively, and are part of the core material 100 held between the intermediate holding rolls 90 and 92. Is rotatable about its axis. Further, the core material 100 is axially movable from a supply roll 86 to a take-up roll 88.

Therefore, the intermediate holding rolls 90 and 92
The core material 100 held in between is continuously magnetron-sputtered, and the outer periphery of the core material 100 is shown in FIG.
The metal thin film 60 shown in FIG. Other steps in the present embodiment are the same as those in the first embodiment, and a description thereof will be omitted.

Fourth Embodiment As shown in FIG. 1B, in this embodiment, a core material 10
As 0a, a hollow synthetic resin tube having an internal passage formed in the axial direction is used. On the whole or a part of the outer peripheral surface of the core material 100a, a magnetron sputtering method similar to that of the above-described embodiment is used.
The medical device 120a is formed by forming the following metal thin film 60.

Core material 10 made of hollow synthetic resin tube
The outer diameter, wall thickness, and length of Oa are appropriately changed according to the use of the medical device 100a and the like. Specific uses of the medical device 120a according to the present embodiment are not particularly limited, and include, for example, a tube member of an IABP balloon catheter and a PTCA balloon catheter, a tube member for an endoscopic treatment instrument having a snare-like wire, and an ophthalmic device. Lacrimal duct, guiding catheter tube member, microcatheter tube member, thin sheath introducer tube member, pacing electrode tube, rotator and atherectomy catheter tube member,
It can be used for various medical tube members such as a tube for an endovascular catheter and an ultrasonic endoscope.

The medical device 120a according to the present embodiment, compared to a medical tube member made of a synthetic resin alone, has an outer peripheral surface of the tubular core material 100a, for example, nickel-based material.
Since the metal thin film 60 made of titanium is formed,
The operating force from the proximal side of the tube is transmitted well to the distal end, and it has excellent push-in characteristics (pushability), excellent flexibility, and can be inserted into a winding part.

Fifth Embodiment As shown in FIG. 1 (C), in this embodiment, first, an outer peripheral surface of a rod-shaped mandrel (not shown) having a circular cross section is
A polymer is deposited by vapor deposition to form a core layer 100b. Next, a metal thin film 60 preferably having a thickness of 50 μm or less is formed on the entire surface or a part of the core material layer 100b by the same magnetron sputtering method as in the above embodiment.
To form Then, on the outer peripheral surface of the metal thin film 60,
The polymer is deposited by vapor deposition to form a skin layer 102 and the mandrel is withdrawn to provide a medical device 120.
b.

The outer diameter, wall thickness, and length of the core material layer 100b and the outer skin layer 102 are appropriately changed according to the use of the medical device 120b. Medical device 120b of the present embodiment
Is not particularly limited, for example, IA
Tube members for BP balloon catheters and PTCA balloon catheters, tube members for endoscopic treatment instruments with snare wires, ophthalmic lacrimal ducts, guiding catheter tube members, microcatheter tube members, small diameter tubes It can be used for various medical tube members such as a tube member for a sheath introducer, a tube for a pacing electrode, a tube member for a rotator and an atherectomy catheter, and a tube for a blood vessel endoscope and an ultrasonic endoscope.

According to the method of manufacturing the medical device 120b according to the present embodiment, a medical tube member which is extremely thin and has elasticity, strength and flexibility can be provided.

The medical device 120b according to the present embodiment
Compared to a medical tube member made of a synthetic resin alone, since the metal thin film 60 made of, for example, nickel-titanium is formed on the intermediate layer of the tube member, the operating force from the hand side of the tube is reduced to the distal side. To communicate well,
It has excellent push-in characteristics (excellent pushability) and excellent flexibility, and can be inserted into winding parts.

Sixth Embodiment As shown in FIG. 5, the medical guide wire 2 according to the present embodiment has a main core portion 5 and a distal end having an average outer diameter smaller than the average outer diameter of the main core portion 5. It has a core wire 4 having a core part 7. The main core portion 5 and the distal end core portion 7 of the core wire 4 are integrally formed of a wire having a substantially circular cross section. The material of the core wire 4 is not particularly limited, but a metal such as stainless steel (for example, SUS316), gold, platinum, aluminum, tungsten, tantalum, or an alloy thereof is exemplified.

The total length L1 of the core wire 4 varies according to the purpose of use and is not particularly limited.
It is about 350 cm, and the core material portion 7 of the core wire 4
Is, for example, about 5 to 50 cm. The outer diameter of the main core material portion 5 of the core wire 4 may be uniform along the axial direction, or may be tapered toward the distal end. The average outer diameter of the main core portion 5 is not particularly limited, but is about 0.15 to 0.90 mm. Also, the outer diameter of the tip core portion 7 may be uniform along the axial direction,
It may be tapered toward the tip. The average outer diameter of the tip core portion 7 is not particularly limited, but is preferably about 1/5 to 1/2 of the average outer diameter of the main core portion 5.

A ball or hemispherical ball portion 10 is joined to the tip of the core portion 7 of the core wire 4. The ball portion 10 smoothes the distal end portion of the guide wire 2,
When the guide wire 2 is inserted into a body cavity such as a blood vessel, the guide wire 2 is a portion for preventing damage to the inner wall of the body cavity as much as possible. The ball portion 10 is made of, for example, a metal such as platinum or gold, and is joined to the tip of the tip core portion 7 by means such as welding. The outer diameter of the ball portion 10 is preferably about 0.5 to 2 times the average outer diameter of the main core portion 5.

The outer periphery of the tip core 7 is covered with a tip-side superelastic metal thin film 6 made of superelastic metal. The metal thin film 6 is made of a superelastic metal such as a nickel-titanium alloy. A superelastic metal has a property that a recoverable elastic strain range is large, for example, reaches 1% to 10%, and in a superelastic region, a force required for deformation is substantially constant even when strain increases. In general, a superelastic metal has an extremely small stress in the superelastic region as compared with the elastic modulus of iron or stainless steel, and is excellent in flexibility. Therefore,
The distal end portion of the guide wire 2 covered with the metal thin film 6 has a property of recovering its original shape after removing the stress.

A core part having the same design as that of the present embodiment may be formed by using a superelastic alloy, and stainless steel, platinum, and other ordinary metals may be deposited on the surface by sputtering. In this case, although the properties are somewhat similar to those of the guide wire of the above-described embodiment, when the guide wire is bent in the blood vessel, the outer surface is subjected to a larger strain than the inside, and the outer surface is easily bent.

The thickness of the metal thin film 6 is not particularly limited, but is about 1 to 100 μm, and preferably 1 to 50 μm. By adjusting this thickness, the superelastic characteristic of the distal end portion of the guide wire 2 can be adjusted. Can be. Although the metal thin film 6 can be formed by a sputtering method, it is particularly preferable to use the same magnetron sputtering as in the above-described embodiment.

The outer peripheral surface of the guide wire 2 is integrally covered with a biocompatible coating film 8. The biocompatible coating film is not particularly limited, for example, olefins such as polyethylene, nitrogen-containing polymers such as polyimide and polyamide, siloxane polymers, and the like.
An ordinary polymer or the like used for medical purposes is used. Further, the coating film is not limited to the polymer, and may be an inorganic coating film such as silicon carbide, carbon such as pyrolite carbon and diamond-like carbon.

In the medical guide wire 2 according to the present embodiment, since the distal end core portion 7 of the core wire 4 is covered with the metal thin film 6 made of a superelastic metal, the distal end portion has excellent elasticity. . Therefore, as shown in FIG. 6, the guide wire 2 is moved from the aorta 22 at the base of the foot to the heart 20.
As in the case of insertion into the coronary artery, the wire tip easily deforms in a blood vessel having a strongly bent portion near the distal end of the wire, and the distal end of the wire is deformably restored. Also,
The base end of the core wire 4 constituting the guide wire 2 is composed of the main core portion 5 and is usually made of metal such as stainless steel, so that the operating force of the base end of the guide wire 2 is reduced by the distal end of the wire. And excellent indentation characteristics. Note that a metal thin film made of a superelastic metal may be provided on the main core portion at the base end within a range that does not affect the insertion characteristics.

In the present embodiment, the distal end portion of the guide wire 2 is not only made of a superelastic metal but has a core portion 7 made of a normal metal. In the present embodiment, the outer periphery of the tip core portion is covered with a metal thin film made of a superelastic metal. However, the covered portion does not need to be the entire outer periphery, and may be part of the outer periphery as long as flexibility can be obtained. May be coated. Depending on the application of the guide wire 2, it is necessary to bend the shape of the distal end portion of the guide wire 2 into a substantially arc shape in advance. In the present embodiment, the guide wire 2 has the distal end core portion 7 usually made of metal. Therefore, bending by plastic deformation is easy. Further, in the present embodiment, since the structure is not such that the main core portion made of a normal metal and the tip core portion made of a superelastic metal are joined, the strength of the joint does not matter.

It should be noted that the present invention is not limited to the above-described embodiment, but can be variously modified within the scope of the present invention.

For example, in each of the above-described embodiments, the metal thin film 6 made of a nickel-titanium alloy and having superelastic characteristics is used.
Although a thin metal tube made of a metal thin tube is manufactured, a medical device having a metal thin film having shape memory characteristics can be manufactured in the same manner according to the manufacturing method of the present invention.

[0046]

As described above, according to the manufacturing method of the present invention, there is provided a medical device capable of freely controlling various properties such as elasticity, rigidity, hardness, electric conductivity and ionization tendency. can do. Further, according to the medical device of the present invention, it is possible to provide a medical device which easily follows a strongly bent portion and is deformable so as to be able to be restored, and which has excellent pushing characteristics.

[Brief description of the drawings]

FIGS. 1A to 1C are cross-sectional views of a main part showing a method for manufacturing a medical device according to an embodiment of the present invention.

FIG. 2 is a schematic view of a magnetron sputtering apparatus used in a method for manufacturing a medical device according to an embodiment of the present invention.

FIG. 3 is a cross-sectional view of a main part of a sputtering apparatus according to another example.

FIG. 4 is a schematic view of a sputtering apparatus according to still another example.

FIG. 5 is a schematic sectional view of a medical guidewire according to one embodiment of the present invention.

FIG. 6 is a schematic view showing an example of use of the guide wire shown in FIG.

[Explanation of symbols]

 2: Guide wire 4: Core wire 5: Main core part 6, 60: Metal thin film 7: Tip core part 8: Biocompatible coating film 12: Coil spring 100, 100a: Core material 100b: Core material layer 102: Outside Cortical layers 120, 120a, 120b ... Medical tools

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) A61M 5/158 A61B 17/10 320 25/00 304 17/11 310 A61N 1/05 A61M 5/14 369B ( 72) Inventor Seiji Shimura 2-28-506 Minamimachi, Toda City, Saitama F-term (reference) 4C053 CC02 CC03 4C060 CC06 DD13 DD16 DD38 EE22 EE28 4C066 FF01 FF04 FF05 PP01 4C081 AC08 BB07 CG01 CG03 DA03 DC06 4C167 AA01 AA AA AA AB AA AA AB AA AB AA AA AB AA AA AB AA AA AA AB AA AA AB AA AA AB AA AA AA AB AA FF01 FF03 FF05 GG02 GG24 GG26 GG31 GG33 GG36 GG41 HH01 HH03 HH04 HH17

Claims (2)

[Claims] 1. A method for manufacturing a medical device, comprising: forming a metal thin film on a surface or an intermediate layer of a member constituting the medical device by sputtering. 2. A medical device having a superelastic metal thin film having a thickness of 50 μm or less.