JP4181354B2 - Medical equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to a medical device such as a guide wire or a stent coated with a hydroxyapatite (hereinafter referred to as apatite) film.
[0002]
[Prior art]
  A medical guide wire (hereinafter referred to as a guide wire) is used for ensuring safety when a catheter is inserted into a lumen such as a cardiovascular vessel. For example, when inserting a catheter of ultra-fine flexible tube for angiography into a blood vessel or when inserting a balloon catheter for treatment of a coronary artery occlusion site into a blood vessel, etc. A guide wire is used to ensure.
  Conventionally, a flexible wire has been used as a guide wire material in order to safely and reliably insert a catheter. For example, known guides in Japanese Patent Publication No. 4-25024, Japanese Patent Publication No. 4-292175, etc. A wire is disclosed.
[0003]
  A guide wire made of a flexible wire does not interfere with a blood vessel even if it is inserted into a blood vessel or a branched blood vessel of a complicated path that bends.
  In addition, when the guide wire travels in the blood vessel, a load is applied to the tip of the guide wire from the direction of travel. Therefore, the guide wire, particularly the tip, has a performance that can withstand the load (vertical loadability and buckling resistance). ) Is required.
  Furthermore, since the distal end portion of the guide wire plays a role of leading the inside of the blood vessel when traveling in the blood vessel, the distal end portion is capable of being restored to the original state even when bent and deformed along the blood vessel path ( (Restorability) is required.
[0004]
  The operation of the guide wire is performed by rotating a hand portion which is a rear end of the guide wire located outside the body. Therefore, the guide wire is also required to have a performance (torsional rigidity) capable of withstanding the rotation accompanying the operation and its operability (steering performance).
  Conventionally, a guide wire in which a spring coil is fitted and welded to a thin main wire has been provided as a guide wire that satisfies the above requirements.
[0005]
  However, when the guide wire is introduced into the branch blood vessel, the pre-shaped portion is formed by slightly deforming the distal end portion of the guide wire into a "<" shape. After a guide wire having a pre-shaped portion at the distal end is inserted into the blood vessel, when the distal end reaches the vicinity of the branch point of the blood vessel, the guide wire is rotated to introduce the pre-shaped portion into the branched blood vessel.
  A guide wire used for introduction into a branch blood vessel is required to be able to easily form a pre-shaped portion in addition to a high degree of flexibility at the distal end portion.
[0006]
  Conventionally provided guide wires are made of Ni (nickel) -Ti (titanium) based superelastic alloy material or SUS (stainless steel) rigid alloy material. For example, it is disclosed in JP-A-9-508538.
[0007]
  On the other hand, a medical stent (hereinafter referred to as a stent) is inserted and placed in order to maintain blood circulation and circulation in a vascular stenosis, and examples of the stent include Japanese Patent Publication No. 9-2703510, 5344 and JP-A-10-328216. These stents have a structure that can be expanded at an indwelling site such as a predetermined blood vessel.
[0008]
  There are various types of stents. For example, a stent that expands after being placed in a blood vessel via a balloon catheter, and is formed from a spiral wound coil spring or a plate shaped in a zigzag pattern. There are some which consist of cylindrical bodies. As materials constituting these stents, materials having good biocompatibility such as heat-sensitive metals, Ni-Ti alloys, SUS materials, titanium, and tantalum that expand after insertion into blood vessels are used.
[0009]
  On the other hand, in the conventional artificial bone and artificial tooth root, apatite (Ca₁₀(PO₄)₆(OH)₂) The film is being coated. This is to provide biocompatibility to the metal surface by coating the surface of the base metal with an apatite film.
[0010]
  Apatite has adsorptivity and ion exchange properties for adsorbing a specific substance, and is therefore used as a filter for removing and purifying unnecessary components in gas and liquid. For example, a filter for gas or liquid filtration using an apatite powder or pellet as a filler is provided.
[0011]
[Problems to be solved by the invention]
  Conventionally, apatite is coated on artificial bones, artificial roots and the like, but medical devices such as guide wires and stents are not coated with apatite. This is because medical devices such as guide wires and stents are composed of a base having a curved surface with a small radius of curvature, and are accompanied by deformation such as bending and bending at the time of use and production. This is because cracking or peeling occurs in the apatite film even if it is coated.
[0012]
  Further, in medical devices such as guidewires and stents, it is required to uniformly coat a resin or the like on the surface or to carry a drug. Thus, it was not easy to uniformly coat a resin or the like and to apply and carry a drug uniformly.
  Conventionally, filters filled with apatite powder, pellets, etc. have been provided as filters for gas or liquid filtration. Today, however, it is desired to provide a filter that is smaller and more excellent in filtration function than this type of filter. It is rare.
[0013]
[Means for Solving the Problems]
  As a means for solving the above-mentioned problems, the present invention constitutes a medical device that is deformed during use.The substrate metal is heated in a high vacuum, and the surface of the substrate metal is coated with a decomposition product of hydroxyapatite in a high vacuum by an excimer laser ablation method. Thereafter, the surface of the coating film made of the decomposition product of hydroxyapatite is coated on the surface. By coating the hydroxyapatite film by an excimer laser ablation method in an atmosphere of water vapor or water vapor-containing gas, the hydroxyapatite film having a thickness of 500 to 8000 mm containing the hydroxyapatite in which the decomposition product is modified is obtained.Part or all of the surface of the base metalToIt provides a medical device that has been trained.
  The apatite film formed by coating on the surface of the base metal must be firmly adhered to the surface. The apatite film is preferably crystallized. The apatite film becomes a ceramic structure by being crystallized, and can exhibit characteristics such as biocompatibility of apatite..
As a method of coating the apatite film of apatite crystallized on the surface of the base metal by the excimer laser ablation method, a method of coating apatite while crystallizing, and a coating of an apatite film made of amorphous amorphous apatite, Then there is a method of crystallizing the apatite of the apatite film by hydrothermal treatment.
[0014]
  In the medical device of the present invention, the surface of the coated apatite film is further coated with a coating material made of resin or the like, and a drug is applied or supported on the surface of the apatite film. Since the medical device of the present invention is coated with the apatite film, it is easy to coat the coating material and to easily apply and carry the drug.
[0015]
  Examples of the medical device of the present invention include a medical guide wire and a medical stent. The medical device of the present invention comprises a substrate having a curved surface with a small radius of curvature, and is bent or bent when the medical device is used or produced. Depending on the specifications of the individual medical device, the curved surface, the bent, etc. The degree of is different.
  Therefore, the thickness of the apatite film is appropriately determined according to each medical device. In the present invention, the thickness of the apatite film is preferably in the range of 500 to 8000 mm, more preferably in the range of 700 to 5000 mm, More desirably, it is in the range of 1000 to 2000 mm. If an apatite film in such a range of thickness is used, the functions of apatite such as biocompatibility, drug loading, adsorption of unnecessary substances, ion exchange, etc. can be exerted, and cracking or peeling of the apatite film Can be prevented. When the thickness of the apatite film is less than 500 mm, the function of the apatite cannot be fully exhibited. When the film thickness is greater than 8000 mm, cracks and peeling occur in the apatite film.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
  Hereinafter, the present invention will be described in detail.
  In the present invention, an apatite film formed entirely or partially on the surface of a base metal of a medical device such as a guide wire or a stent is formed by an excimer laser ablation method.
  An outline of an apparatus used in the excimer laser ablation method will be described with reference to FIG.
  As shown in FIG. 1, in the vacuum film formation chamber (1), the base metal (3) (wire) is wound around the reel (16) for feeding out the base metal (3) and the base metal (3). A target (5) obtained by pressing an apatite powder with a mold is placed opposite to the base metal (3). When an apatite film is formed only at a predetermined location, a shielding mask is provided around the location of the base metal (3) where the apatite film is not formed.
[0017]
  In this state, the exhaust system (2) in the vacuum chamber (1) is evacuated to a predetermined degree of vacuum by the rotary pump and the turbo molecular pump. After exhausting, the base metal (3) is heated to a predetermined temperature by the heater (4). NextAThe target (5) is irradiated with an rF excimer laser (7) to release atoms and ion clusters which decomposed apatite and coat the surface of the opposing base metal (3) with an apatite decomposition product film.
  Furthermore, water vapor or water vapor-containing gas is introduced into the vacuum chamber (1) from the gas introduction nozzle (6),ArF excimer laser again (7) The target (Five) To form an apatite film on the surface of the apatite decomposition product film,The apatite decomposition product film is transformed into an apatite film.
[0018]
  As the water vapor-containing gas, oxygen gas-water vapor mixed gas, argon gas-water vapor mixed gas, helium gas-water vapor mixed gas, nitrogen gas-water vapor mixed gas, air-water vapor mixed gas, or the like is used.
  In this case, when the gas pressure of the water vapor or water vapor-containing gas is increased, that is, when the atmosphere of the water vapor or water vapor containing gas is increased, the apatite decomposition component is crystallized and grows on the surface of the base metal (3) while coating the apatite. This is an in-situ method.
  On the other hand, when the gas pressure of water vapor or water vapor-containing gas is lowered, that is, in a low atmosphere of water vapor or water vapor containing gas, a coating in which amorphous apatite is deposited on the surface of the base metal (3) is obtained. In this case, after coating, the amorphous apatite is crystallized by hydrothermal treatment (post-annealing method) in high-temperature steam.
[0019]
  A medical device such as a guide wire and a stent on which the apatite film of the present invention is formed will be described.
  The guide wire (18) is made of a flexible fine wire main wire as shown in FIG. The distal end portion (20) of the guide wire (18) is inserted into the blood vessel (23), and the distal end portion (20) is inserted into the branch blood vessel (24) (see FIG. 3) during the insertion. 20) is processed with a small diameter. When the distal end portion (20) of the guide wire (18) is introduced to a predetermined location in the blood vessel, it is performed by operating the main wire (hand portion (19)) on the proximal side. For this reason, the guide wire (18), in particular the tip (20), is required to have a structure and its constituent materials so that the tip (20) can be reliably introduced into a predetermined location by operating the hand (19). ing.
  Further, as the distal end portion (20) of the guide wire (18), a distal end portion in which the main wire is reduced in diameter, a distal end portion in which an extra fine coil is welded, a distal end portion coated with a resin such as fluororesin, or the like is used.
  As a constituent material of the distal end portion (20) of the guide wire (18), a known material used for insertion into the body such as a SUS material or a Ni-Ti material is used.
  The surface of the distal end portion (20) is coated with a lubricant or a drug for improving slippage during blood vessel insertion. These drugs are composed of organic compounds, and the drugs have good adhesion to the apatite film.
  By forming an apatite film (25) at the tip (20) of the guide wire (18) and modifying the surface of the tip (20), the coating and the drug can be easily carried. The biocompatibility of the guide wire (18) is also improved by the apatite film (25).
  As the tip portion (20) on which the apatite film is formed, the tip portion (20) of the main wire as shown in FIG. 2 or the tip portion (20) as welded with the spring coil (21) as shown in FIGS. ) When the apatite film (25) is formed on the spring coil (21), coating is performed before the coil (21) is welded, and the apatite film (25) is applied to the entire surface of the wire (22) of the coil (21). (See FIG. 5), or after welding, an apatite film (25) is formed on the surface of the coil (21), that is, on the surface of a part of the wire (22) of the coil (21). It is also possible (see FIG. 6).
[0020]
  The main wire constituting the proximal portion (19) of the guide wire (18) is required to have excellent mechanical properties such as rigidity. Therefore, when the guide wire (18) is introduced into the blood vessel, the surface of the guide wire (18) is coated with a lubricant or the like in order to improve the slip of the hand portion (19).
[0021]
  A stent (26) is shown in FIGS. The stent (26) has an expandable structure, and is composed of a cylindrical body having a mesh structure made of fine fine metal wires. The stent (26) is inserted into the catheter in a contracted state with a balloon inserted therein. The stent (26) expands by inflating a balloon at a predetermined location of the blood vessel. Therefore, the stent (26) is required to have a strength that can withstand the external pressure applied during expansion or after placement.
  The material used for the stent (26) is a known material that can be used in vivo, such as a SUS material.
  In some cases, a drug or the like is carried on the entire outer surface and / or inner surface of the stent (26). Therefore, if an apatite film is formed on the surface of the stent (26), it becomes possible to easily carry a drug or the like. In addition, the biocompatibility of the stent is improved by the apatite film.
[0022]
  The apatite film formed on the surface of the base metal of the medical device of the present invention may be formed entirely on the surface of the base metal, or may be partially formed at a necessary location.
  The medical device in which the apatite film of the present invention is effectively formed is a material having a curved surface with a small curvature radius, such as a guide wire or a stent, or a material in which the base metal is bent or deformed during use or production. .
[0023]
  On the apatite film of the present invention, a coating material made of a resin (for example, silicone resin, fluororesin, etc.) is coated, or a drug such as a lubricant, an antithrombotic agent, an X-ray contrast agent, a therapeutic drug, Loading is performed.
  Some coating materials and drugs (hereinafter referred to as drugs) are hydrophilic and some are hydrophobic, and some drugs and the like cannot be directly supported on the metal surface.
  Coating of the coating material on the apatite film of the present invention, application of a drug, etc. can be easily carried. Apatite has hydrophilic OH groups and hydrophobic PO₄This is because a group exists.
  The medical device of the present invention can easily apply a coating material, apply a drug, etc., and carry it by modifying the surface of a substrate made of a metal such as a guide wire with an apatite film.
[0024]
  A test piece was prepared from the base metal on which the apatite film of the present invention was formed, and the test for the bending strength of the test piece was performed. The contents of the test will be described below.
  An apatite film having a thickness of 500 mm, 1000 mm, 3000 mm, 5000 mm, and 10,000 mm is formed on the surface of the base metal surface made of SUS316 (thickness: 0.05 mm, width: 0.2 mm) by ArF excimer laser ablation, respectively. Test pieces B, C, D, E and F were formed on the top. A test piece A was also prepared as a test piece on which an apatite film was not formed.
  The test pieces A to F obtained as described above were subjected to a three-point bending test (span length: 5 mm) using a bending tester, and the bending load up to a bending displacement of 1 mm was measured. The results are shown in FIG. 10 and FIG.
[0025]
  As described above, the desired film thickness of the apatite film in the present invention is in the range of 500 to 8000 mm. If the film thickness is in this range, the rigidity of the base metal hardly changes even if the apatite film is formed. .
  Therefore, even if an apatite film having a film thickness within the above range is formed on the surface of the base metal, it is possible to modify the metal surface without changing the mechanical properties of the base metal, particularly the bending strength. It was confirmed that there was.
[0026]
  Further, test pieces (test piece G (film thickness 0 mm), H (film thickness 500 mm), I (film thickness 1000 mm), J (film thickness 3000 mm), K (film thickness) obtained by forming an apatite film on the base metal. 6000 mm), L (film thickness 8000 mm) and M (film thickness 10,000 mm)) were applied to a tensile tester to observe the cracks and peeled state of the apatite film of each test piece. The results are summarized in FIG.
  The hatched area in FIG. 12 indicates a range in which neither cracking nor peeling occurs with respect to the tensile displacement. From the above test results, it was found that the thinner the apatite film, the better the adhesion to the base metal. Further, if the thickness of the apatite film is up to about 3000 mm, the apatite film can withstand a displacement of 30% of the base metal, and even if the film thickness is about 8000 mm, the apatite film can withstand a displacement of 10%. I understood.
  In general, the base metal for use in medical devices such as guide wires and stents and other devices is deformed at the time of use or deformed at the time of manufacture, but usually the base metal is deformed by 10% or more. There are few cases. Therefore, in the apatite film of the present invention, the film thickness is set in the range of 8000 mm or less, and the film thickness is set according to the specifications to prevent the occurrence of cracks and peeling.
[0027]
  The apatite film of the present invention has biocompatibility. The thinner the film thickness, the better the adhesion of the apatite film to the base metal, but the biocompatibility may be lowered. Therefore, in order to investigate the relationship between the thickness of the apatite membrane and the biocompatibility, a cell culture experiment of fibroblasts was performed. The experimental method is described below, and the experimental results are shown in FIG.
[0028]
  Apatite films having a thickness of 500 mm, 1000 mm, and 3000 mm were formed on the surface of each base metal (SUS304L material) by excimer laser ablation to obtain test pieces O, P, and Q. For comparison, a test piece N (without apatite film) was also prepared. These specimens N, O, P and Q were autoclaved in an autoclave.
[0029]
  Mouse fetal harvested third-generation fibroblasts (hereinafter referred to as fibroblasts) were adjusted to a cell density of 2.5 × 10 5 using a cell culture medium (Dulbecco's displacement Eagle medium with 10% fetal bovine serum, DMEM).⁴Per unit / ml.
[0030]
  1 ml of the prepared fibroblasts and each test piece were placed in one hole of a 4-well plate, respectively, and were placed in a carbon dioxide culture container (temperature: 37 ° C., carbon dioxide: 5.0%) for 1 day and 2 days. And cultured for 3 days.
  After each culture, the test piece was taken out, and unfixed fibroblasts were washed out from the test piece with Dulbecco's phosphate buffer (cell washing solution). Subsequently, the cells were placed in ethylenediaminetetraacetic acid compound trypsin (proteolytic enzyme) and left for 1 minute to peel off the cells adhering to the test piece. After detachment, 1 ml of the cell culture solution was added, 1 μl was taken out, and the number of cells was read with a blood cell conversion plate. The number of cells read is 10⁴The cell density was multiplied by 1 ml, and the vertical axis in FIG.
[0031]
  From the result of FIG. 13, when the film thickness is 500 mm or more, biocompatibility that is a function of the apatite film can be exhibited.
  In FIG. 13, the number of cells is 11 × 10.⁴The reason why the cell growth is stagnant in the vicinity of the individual cells is that the cells have reached the growth saturation limit.
[0032]
  Hereinafter, the present invention will be described by way of examples. However, this invention is not limited only to the Example shown below.
  [Example 1]
  FIG. 14 shows a guide wire (27) having an apatite film (38). SUS304 stainless fine wire was used as the main wire (28) of the guide wire (27). The outer diameter of the proximal portion (29) of the guide wire (27) is 0.33 mmφ, and the total length of the guide wire (27) is 1800 mm. Further, the guide wire (27) is processed into a small diameter by gradually reducing the wire diameter with a centerless grinder from the hand portion (29) to the tip portion (30). The most advanced part (31) is ground and polished to a length of 40 mm and a diameter of 0.06 mm.
  The distal end portion (30) of the guide wire (27) includes a front end portion (31), a first taper portion (32) (length: 50 mm) connected to the front end portion (31), and the first taper. The first same-diameter portion (33) (length 60 mm, outer diameter 0.15 mmφ) connected to the portion (32), and the second tapered portion (34) (length) connected to the first same-diameter portion (33) 45 mm).
  On the other hand, the proximal portion (29) of the guide wire (27) is a second same diameter portion (35) (length 80 mm, outer diameter 0.185 mmφ) connected to the second taper portion (34) of the tip portion (30). A third taper portion (36) (length: 60 mm) connected to the second taper portion (35), and a third taper portion (37) (outside) connected to the third taper portion (36). (Diameter 0.33 mmφ, length 1420 mm).
  An apatite film (38) (film) on the surface of the tip part (30) excluding the most advanced part (31), that is, the first taper part (32), the first same diameter part (33) and the second taper part (34). The thickness was 3000 to 5000 mm.
  On the other hand, the surface of the second taper part (34), the second same diameter part (35), the third taper part (36) and the third same diameter part (37) of the hand part (29) is fluororesin (39). Is covered.
[0033]
  [Example 2]
  FIG. 15 shows a guide wire (40) having an apatite film (46) as another embodiment. A very thin spring coil (44) is welded to the tip (41) of the guide wire (40). As the main wire (42) of the guide wire (40), SUS304 stainless steel was used.
  The outer diameter of the proximal portion (43) of the guide wire (40) is 0.34 mmφ, and the total length of the guide wire (40) is 1800 mm.
  The guide wire (40) is tapered from a portion 1450 mm from the rear end of the hand portion (43) to the front end portion (41).
  The spring coil (44) welded to the tip (41) is a tightly wound coil made of a thin wire of SUS316 stainless steel having an outer diameter of 0.07 mm. The length of the spring coil (44) is 300 mm. The most distal portion (45) (30 mm) of the spring coil (44) is made of a thin Pt—Ni wire. The spring coil (44) is obtained by previously welding a SUS316 thin wire and a Pt-Ni thin wire to 0.07 mmφ before winding the coil, and winding the coil around the coil.
  The leading edge (45) serves as an X-ray visual marker for tip position confirmation when the guide wire (40) is used.
  An apatite film (46) is formed on the entire surface of the hand portion (43) of the guide wire (40) of the present embodiment, and a coating material (47) made of a fluororesin is further formed on the apatite film (46). Is covered.
  In addition, a silicone resin (polydimethylsiloxane) is coated on the forefront portion (45) made of the fine Pt—Ni wire.
  Since the apatite film (46) is formed on the proximal portion (43) of the guide wire (40) of this example, the coating material (47) of fluororesin could be easily covered.
[0034]
Example 3
  FIG. 16 shows a guide wire (48) having an apatite film (52) as still another embodiment. The guide wire (48) is usually called a plastic guide wire and has a total length of 1500 mm. The main wire (49) (outer diameter 0.56mmφ) of the guide wire (48) is made of three thin wires (SUS304 material with an outer diameter of 0.28mmφ) as an S-wound stranded wire and swaging the stranded wire It is.
  The tip (50) of the main wire (49) has the same diameter (outer diameter of 0.20 mmφ) at the most advanced portion (52) (30 mm), but the main wire (49) except for the most advanced portion (51). ) With a centerless grinder to form a taper shape (180 mm).
  Further, the tip part (50) is formed with an apatite film (52) (film thickness is 3000 mm) from the most advanced part (51) to a position of 70 mm.
  Further, a coating material (53) made of a nylon resin mixed with bismuth trioxide (50% by weight) is coated on the apatite film (52), and a hydrophilic polymer is further coated on the coating material (53). (54) (Main component is polyvinylpyrrolidone).
  The outer diameter of the main wire (49) coated with the nylon resin coating material (53) is 0.80 mmφ, and the outer diameter of the main wire (49) coated with the hydrophilic polymer (54) is 0.85 mmφ.
  By forming the apatite film (52) on the tip (50) of the main wire (49), the surface of the tip (50) can be modified without impairing the operability of the guide wire (48). Thus, the nylon resin coating material (53) could be firmly adhered onto the apatite film (52).
[0035]
  Example 4
  FIG. 17 shows a stent (55) having an apatite film (57, 57). The stent (55) is composed of a mesh-shaped cylindrical body (56) (outer diameter: 2.5 mm, length: 23 mm) made of thin SUS316L thin wire (plate thickness: 0.05 mm) as shown in FIG. . The stent (55) is obtained by processing a thin cylindrical material by photoetching, and has a structure that can be expanded at the time of indwelling after being inserted into an affected part in the body.
  An apatite film (57, 57) was formed to a thickness of 500 to 1000 mm on the inner surface and the outer surface of the cylindrical body (56).
  In the stent (55) of this example, the apatite membrane (57, 57) can easily carry a drug such as an antithrombotic agent.
[0036]
  Example 5
  FIG. 18 shows a coil (58) used for a filter for liquid filtration. This coil (58) consists of 3 layers (1st layer coil (59), 2nd layer coil (60) and 3rd layer coil (61)), SUS with a diameter of 0.07mmφ coated with apatite film (62). Fine wire, outer diameter (D₁) = 0.59mmφ, inner diameter (D₂) = Coil (58) wound to be 0.3 mmφ.
  The filter bundles a plurality of coils (58), and the liquid passes through the slits between the windings from the inner side to the outer side of the coil (58) for filtration.
  As the liquid passes through the narrow gaps between the thin wires coated with the apatite film (62), unnecessary substances in the liquid are adsorbed or ion-exchanged.
  Since the constituent material of the filter is a thin metal wire coated with an apatite film (62), the filter can be filtered even when the liquid is hot. Further, since the filter has high strength, it is possible to back-wash the filter.
[0037]
  The medical device having the apatite film of the present invention is configured by setting the film thickness of the apatite film so that it can withstand the deformation even when it is used or produced with a large deformation (bending, bending). The problem of cracking and peeling of the apatite film was solved. In the medical device of the present invention, the surface of the base metal is modified by the apatite film, that is, the biocompatibility is good, and it is possible to easily carry the drug and coat the coating material. became.
  In addition, in equipment that uses the adsorptivity and ion exchange properties that are characteristic of apatite, as a composite material in which the constituent base material is a metal and the surface is coated with apatite in the case of requiring mechanical strength during use. Configurable. By appropriately setting the coating thickness of the apatite, it became possible to produce a device that can sufficiently withstand deformation during device fabrication or use.
  In particular, it has become possible to perform high-temperature filtration and production of a filter using a wire or plate coated with apatite.
[0038]
【The invention's effect】
  Cracks and peeling do not occur in the apatite film coated on the medical device such as the guide wire and the stent of the present invention.
[Brief description of the drawings]
[Fig. 1] Outline of excimer laser ablation system
FIG. 2 is an explanatory view of a partial cross section of a guide wire
FIG. 3 is an explanatory diagram of a guide wire introduced into a branch vessel
FIG. 4 is a cross-sectional view of the tip of a guide wire with a spring coil
FIG. 5 is a cross-sectional view of the guide wire of FIG.
6 is a cross-sectional view of the guide wire of FIG.
FIG. 7 is a partial explanatory view of a stent.
FIG. 8 is an enlarged view of the stent of FIG.
9 is an explanatory view of an expanded state of the stent of FIG.
FIG. 10 is a diagram for explaining the relationship between bending displacement and bending load in a three-point bending test of a test piece having an apatite film.
FIG. 11 is a diagram for explaining a relationship between a thickness of an apatite film and a bending load in a three-point bending test of a test piece having an apatite film.
FIG. 12 is a diagram illustrating the relationship between tensile displacement and occurrence of cracks in an apatite film in a tensile test of a test piece having an apatite film.
FIG. 13 is a graph showing the relationship between the number of days in culture and the number of cells in a fibroblast culture test of a test piece having an apatite film.
  FIG. 14 shows an embodiment of the present invention.
FIG. 14 is a partial sectional view of a guide wire on which an apatite film is formed.
  FIG. 15 shows another embodiment of the present invention.
FIG. 15 is a partial cross-sectional view of a guide wire with a spring formed with an apatite film.
  FIG. 16 shows still another embodiment of the present invention.
FIG. 16 is a partial sectional view of a plastic guide wire on which an apatite film is formed.
FIG. 17 shows still another embodiment of the present invention.
FIG. 17 is a partial sectional view of a stent formed with an apatite film.
FIG. 18 is a side view of a three-layer coil filter made of fine wires on which an apatite film is formed.
[Explanation of symbols]
  1 Vacuum deposition chamber
  2 Exhaust system
  3 Base metal
  4 Heater
  5 Apatite target
  6 Gas introduction nozzle
  7 ArF excimer laser light source
  8 Mirror
  9 Lens
  10 windows
  11 Slit
  12 Heater temperature controller
  13 Thermometer
  14 Film thickness meter
  15 Gas introduction route
  16 feed reel
  17 Take-up reel
  18 Guidewire
  19 Hand
  20 Tip
  21 Spring coil
  22 Spring coil wire
  23 Blood vessels
  24 branch vessels
  25 Apatite film
  26 Stent
  27 Guide wire
  28 Main wire
  29 Hand
  30 Tip
  31 Cutting edge
  32 1st taper part
  33 First diameter part
  34 Second taper part
  35 2nd same diameter part
  36 3rd taper part
  37 3rd same diameter part
  38 Apatite film
  39 Fluororesin
  40 guidewire
  41 Tip
  42 Main wire
  43 Hand
  44 Spring coil
  45 The most advanced part of the spring coil
  46 Apatite film
  47 Coating material (fluororesin)
  48 Guidewire
  49 Main wire
  50 Tip
  51 Cutting Edge
  52 Apatite film
  53 Coating material (nylon resin)
  54 Hydrophilic polymer
  55 stent
  56 Cylindrical body
  57 Apatite film
  58 Filter coil
  59 1st layer coil
  60 Second layer coil
  61 3rd layer coil
  62 Apatite film

Claims (7)

The substrate metal constituting a medical device with deformation during use is heated in high vacuum, and the surface of the substrate metal is coated with the decomposition product of hydroxyapatite in high vacuum by the excimer laser ablation method. By coating a hydroxyapatite film by an excimer laser ablation method in a water vapor or water vapor-containing gas atmosphere on the surface of the coating film made of the decomposition product of the above, medical equipment, characterized in that the hydroxyapatite film was co computing part or all of the base metal surface. The medical device according to claim 1, wherein the hydroxyapatite film is crystallized. The medical device according to claim 1 or 2 , wherein the surface of the hydroxyapatite film is further coated with a coating material made of a resin. The medical device according to any one of claims 1 to 3 , wherein a drug is further applied or supported on the surface of the hydroxyapatite film. The medical device according to any one of claims 1 to 4 , wherein the medical device is a medical guide wire. The medical device according to any one of claims 1 to 5 , wherein the medical device is a medical stent. The medical device according to claim 1 , wherein the hydroxyapatite film formed on the surface of the base metal is crystallized by hydrothermal treatment.

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