JP2014100330A - Catheter tube manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a catheter tube manufacturing method capable of manufacturing catheter tubes while favorably joining a plurality of tubular bodies arranged in an axial direction.SOLUTION: A catheter tube manufacturing method comprises: an external coat layer body forming step for forming a coat body 53 by covering, radially outward of a core wire 40, a plurality of resin-made coat members 70A, 70B, 70C provided in a radial direction and forming one cylindrical shape as a whole, then joining the coat members 70A, 70B, 70C by pressing and heating the coat members 70A, 70B, 70C radially inward and by applying a twisting force around a radial line of the core wire 40, and then applying a coat; and a core wire removing step, following the external coat layer body forming step, for removing the core wire 40 from discrete tubes 61 obtained on the core wire 40.

Description

  The present invention relates to a method for manufacturing a catheter tube used for a catheter used in a lumen such as a blood vessel or a body cavity.

  In recent years, treatment in a lumen such as a blood vessel or a body cavity using a catheter has been actively performed for the reason that surgical invasion is very low. For example, catheters that are selectively introduced into complex branched blood vessels in the body are typically selectively pushed along a guide wire that is pre-introduced into the blood vessel to provide therapeutic drugs and diagnostics. The contrast agent for use is distributed from the proximal side (base end side) to the distal end side. For this reason, the long catheter tube constituting the catheter has a large inner and outer diameter on the proximal end side, thereby improving rigidity and providing sufficient pushability. The injection characteristic is secured, the inner and outer diameters on the distal end side are made thinner than the proximal end side, and it is made flexible to improve the reachability to the peripheral blood vessels and the followability to the guide wire.

  As a method for manufacturing such a catheter tube, for example, Patent Document 1 discloses that a resin inner layer tube is formed on a core wire, and another resin tube is used to give different characteristics depending on the part. Cover the body with a heat-shrinkable tube and heat the heat-shrinkable tube to melt or soften the tube while pressing it to form another covering on the inner tube, then pull out the core wire and remove it. A method of manufacturing a catheter tube is described.

US Pat. No. 6,464,684 Specification

  However, in the method described in Patent Document 1 described above, when a plurality of tubes are arranged in the axial direction and each tube is pressed while being heated, the coupling between the tubes arranged in the axial direction becomes insufficient. There may be cases.

  The present invention has been made to solve the above-described problems, and provides a method for manufacturing a catheter tube that can manufacture a catheter tube while satisfactorily connecting a plurality of tubes arranged in the axial direction. With the goal.

  A method of manufacturing a catheter tube that achieves the above object is provided in the axial direction on the outer side in the radial direction of the core wire so as to form a single cylindrical shape as a whole, or in the axial direction and in the circumferential direction. A covering member made of resin that constitutes a single cylindrical shape as a whole is covered, and the covering member is heated while pressing inward in the radial direction, and a torsional force is applied around the axis of the core wire. A covering body forming step of forming a covering body by bonding a plurality of the covering members together, and a core wire removal for removing the core wire from the single tube obtained on the core wire after the covering body forming step And a method for producing a catheter tube.

  The method of manufacturing a catheter tube configured as described above includes heating a resin coating member disposed on the radially outer side of the core wire while pressing the resin coating member toward the radially inner side, and applying a torsional force. Thus, the catheter tube can be manufactured while the covering members arranged in the axial direction are well connected to each other.

  In the covering body forming step, a heat shrinkable tube is covered on the radially outer side of the covering member, and a twisting force is applied to the heat shrinkable tube around the axis of the core wire while heating the heat shrinkable tube. For example, a twisting force can be easily applied to the heat-shrinkable tube while applying a pressing force using the contraction force of the heat-shrinkable tube that shrinks when heated.

  If the core wire is formed in advance with a large diameter portion and a small diameter portion having different outer diameters, catheter tubes having different diameters on the distal end side and the proximal end side can be efficiently manufactured on the core wire.

  In the core wire, a large-diameter portion and a small-diameter portion having different outer diameters are continuously formed in advance at a predetermined interval, and in the cutting step, the tubular continuous body obtained on the core wire is converted into a large-diameter portion and a thin portion of the core wire. If a plurality of the single tubes are cut out at a predetermined position of the diameter portion, catheter tubes having different diameters on the distal end side and the proximal end side are continuously formed on the core wire. While producing efficiently.

  If the catheter further includes a reinforcing body forming step of forming a reinforcing body made of a wire material on the radially inner side or the outer side of the covering body before or after the covering body forming step, the manufactured catheter tube Can be reinforced in accordance with the above, and the pushability and kink resistance can be improved.

  Before or after the covering body forming step, a plurality of other covering body forming steps for forming another covering body by coating a resin inside or outside in the radial direction from the covering body, A catheter tube having a multilayer structure composed of layers can be efficiently manufactured using a core wire.

It is a top view which shows a catheter. It is sectional drawing which shows the tube for catheters manufactured by the manufacturing method of the tube for catheters concerning embodiment. It is a figure for demonstrating the manufacturing method of the tube for catheters which concerns on embodiment to process order, (A) is a core wire preparation process, (B) is an inner layer covering body formation process, (C) is a reinforcement body formation process, (D ) Is a marker placement step, (E) is a cutting step, (F) is an outer layer covering body forming step, (G) is a core wire stretching step, (H) is a core wire removing step, and (I) is a hydrophilic covering body forming step. Show. It is the schematic for demonstrating the method of forming a layer by extrusion molding. It is the schematic for demonstrating the method of forming a layer by dip molding. It is the schematic for demonstrating the method of forming a layer using a heat contraction tube. It is a top view for demonstrating the modification of an outer layer covering body formation process. It is a top view for demonstrating when forming an outer layer covering by the modification of an outer layer covering forming process. It is a top view which shows the modification of a core wire. It is a top view which shows the other modification of a core wire.

  Embodiments of the present invention will be described below with reference to the drawings. In addition, the dimension ratio of drawing is exaggerated on account of description, and may differ from an actual ratio.

  A catheter tube 10 manufactured by the catheter tube manufacturing method according to the present embodiment is inserted into a blood vessel, bile duct, trachea, esophagus, urethra, or other living body lumen or body cavity as shown in FIG. It is used for the catheter 1 for performing treatment and diagnosis. The catheter 1 includes a long catheter tube 10, a hub 20 connected to the proximal end of the catheter tube 10, and a kink protector 30 provided at a connection portion between the catheter tube 10 and the hub 20. ing. In this specification, the side to be inserted into the lumen is referred to as “tip” or “tip side”, and the proximal side to be operated is referred to as “base end” or “base end side”.

  As shown in FIGS. 1 and 2, the catheter tube 10 is a tubular member having flexibility, a tube base end portion 11 having a predetermined outer diameter and an inner diameter, and an outer diameter smaller than the tube base end portion 11. And a tube transition portion 13 in which the outer diameter and the inner diameter gradually change in the axial direction between the tube proximal end portion 11 and the tube distal end portion 12. The catheter tube 10 has a lumen 14 formed from the proximal end to the distal end. The lumen 14 functions as a guide wire lumen, for example, and the guide wire is inserted when the catheter 1 is inserted into the living body lumen. The lumen 14 can also be used as a passage for a chemical solution, an embolic material, a contrast medium, or the like.

  The catheter tube 10 is composed of a plurality of layers, an inner layer 15 constituting the innermost layer, a reinforcing layer 16 formed outside the inner layer 15, and an outer layer formed outside the inner layer 15 and the reinforcing layer 16. 17, a hydrophilic layer 18 that covers the outer side of the outer layer 17, and a marker 19. In addition, the structure and material of the inner layer 15, the reinforcement layer 16, the outer layer 17, and the hydrophilic layer 18 are demonstrated in detail by the manufacturing method mentioned later.

  In the hub 20, the proximal end portion of the catheter tube 10 is fixed in a liquid-tight manner by an adhesive, heat fusion, a stopper (not shown) or the like. The hub 20 functions as an insertion port for a guide wire into the lumen 14, an injection port for a drug solution, an embolic material, a contrast medium, etc. into the lumen 14, and also functions as a grip portion when operating the catheter 1. To do. Although the material of the hub 20 is not particularly limited, for example, a thermoplastic resin such as polycarbonate, polyamide, polysulfone, polyarylate, methacrylate-butylene-styrene copolymer can be suitably used.

  The kink protector 30 is made of an elastic material provided so as to surround the circumference of the catheter tube 10, and suppresses kinking of the catheter tube 10 at a connection portion between the catheter tube 10 and the hub 20. As a material for the kink protector 30, for example, natural rubber, silicone resin, or the like can be preferably used.

  Next, a method for manufacturing the catheter tube 10 according to the present embodiment will be described. The catheter tube 10 includes a core wire preparation step (FIG. 3A) for preparing a long core wire 40, and an inner layer cover body formation step (cover body formation) for forming an inner layer cover body 51 (cover body) on the core wire 40. Step) (FIG. 3B), a reinforcing body forming step for forming the reinforcing body 52 on the inner layer covering body 51 (FIG. 3C), and a marker placement step for placing the marker 19 on the reinforcing body 52 (FIG. 3 (D)), a cutting step (FIG. 3 (E)) for cutting the tubular continuous body 60 obtained on the core wire 40 after the marker placement step and cutting the single tube 61, and forming the outer layer covering 53. Outer layer covering formation process (FIG. 3 (F)), core wire stretching process for stretching the core wire 40 (FIG. 3 (G)), and core wire removal process for removing the core wire 40 from each single tube 61 (FIG. 3 (H)) And a hydrophilic covering forming step for covering the hydrophilic covering 54 Figure 3 (I)), a has. The inner layer covering body 51, the reinforcing body 52, the outer layer covering body 53, and the hydrophilic covering body 54 formed on the core wire 40 are finally the inner layer 15, the reinforcing layer 16, the outer layer 17, and the hydrophilic layer 18 of the catheter tube 10. It becomes.

  As shown in FIG. 3 (A), the core wire preparation step is performed by mechanical processing such as drawing, drawing, or the like using a cutting die, cutting, polishing, grinding, forging, welding, split die, or chemical processing such as etching. , A step of processing to have the large-diameter portion 41, the small-diameter portion 42, and the transition portion 43, or a step of preparing the core wire 40 subjected to the above-described processing by purchase or the like.

  The core wire 40 prepared in the core wire preparation step includes a large diameter portion 41 having a predetermined outer diameter, a small diameter portion 42 having an outer diameter smaller than the large diameter portion 41, and between the large diameter portion 41 and the small diameter portion 42. A plurality of transition portions 43 whose outer diameters gradually change in the axial direction of the core wire 40 are arranged side by side. The ratio (D1 / D2) of the outer diameter D1 of the large diameter portion 41 to the outer diameter D2 of the thin diameter portion 42 of the core wire is preferably more than 1.00 and 1.31 or less, more preferably 1.30 or less. More preferably, it is 1.22 or less. The ratio (D1 / D2) is greater than 1. When the ratio (D1 / D2) is 1.31 or less, not only the small-diameter portion 42 but also the large-diameter portion 41 is satisfactorily stretched in the core wire stretching step, and the thinning of only the small-diameter portion 42 is suppressed. The core wire 40 can be removed well in the removing step, and the catheter tube 10 that can withstand actual use can be manufactured. If the ratio (D1 / D2) is 1.22 or less, the thinning of only the small-diameter portion 42 is more reliably suppressed, and the core wire 40 can be more reliably removed in the core wire removing step. The catheter tube 10 can be manufactured. As an example, the length L1 of the large diameter portion 41 is 1800 mm, the length L2 of the small diameter portion 42 is 150 mm, the length L3 of the transition portion 43 is 50 mm, and the outer diameter D1 of the large diameter portion 41 is 0.55 to. Although the outer diameter D2 of 6 mm and the thin diameter part 42 can be 0.45-0.50 mm, a dimension is not limited to this.

  The material of the core wire 40 can be a metal such as a copper wire or a stainless steel soft wire, or a resin strand such as polyamide (PA), and the cross section is not limited to a circle, but can be any shape such as an ellipse, a semicircle, a polygon, etc. It can be made into the shape. The core wire 40 as described above can be easily prepared by purchase or the like.

  After the core wire preparation step, as shown in FIG. 3B, an inner layer covering 51 is formed on the core wire 40 (an inner layer covering step (covering step)). As the material of the inner layer covering 51, a thermoplastic resin, a thermosetting resin, or the like can be applied, and a low friction material such as a fluorine-based resin or high-density polyethylene (HDPE) is preferable.

  The inner layer covering 51 may be mixed with a radiopaque material. When the inner layer covering 51 is formed of a low friction material such as a fluororesin, the outer surface of the inner layer covering 51 is roughened by chemical etching or the like so that other materials can be covered on the outer side. It is preferable to perform the treatment.

  When a thermoplastic resin is used as the material of the inner layer covering 51, it can be extruded at a predetermined take-up speed at a predetermined molding temperature (die temperature) with an extruder. Thereby, the extrusion molding (inner layer covering 51) of substantially the same thickness can be obtained. As an example, the outer diameter of the inner layer covering 51 in the portion corresponding to the large diameter portion 41 is 0.57 to 0.76 mm, and the outer diameter of the inner layer covering 51 in the portion corresponding to the small diameter portion 42 is 0.47 to 0. 0.53 mm, but the dimensions are not limited to this. In addition, by adjusting the take-up speed, the wall thickness can be changed according to the part.

  An outline of the extrusion molding method is as follows. Using a general extrusion molding machine 100 as shown in FIG. 4, a thermoplastic resin layer (here, inner layer covering 51) on the core material W (here, the core wire 40). ). The extrusion molding machine 100 includes an extruder 101 for extruding the heated and melted material, a mold 103 for extruding the resin extruded from the extruder 101 from the extrusion port 102, and a position passing through the mold 103 at the center of the extrusion port 102. A take-up machine 105 for picking up the core material W to be wound, a supply roll 106 for supplying the core material W to the mold 103 while the core material W is wound and held, and a recovery for recovering the core material W that has been extruded. A roll 107. When extruding a material onto the core material W, the material heated and melted by the extruder 101 is supplied to the mold 103, and sent from the supply roll 106 to take out the core material W located at the extrusion port 102. The material is continuously supplied from the extrusion port 102 onto the core material W while being taken up by 105, and the material is coated on the core material W. The core material W coated with the material is wound around the collection roll 107 and collected after the coated material is solidified. By changing the take-up speed by the take-up machine 105, the outer diameter of the extruded product can be arbitrarily changed. If the core material W is directly received from the previous process and the core material W coated with the thermoplastic resin is directly transferred to the subsequent process, the supply roll 106 and the recovery roll 107 may not be provided. In the extrusion molding of the inner layer covering 51, when a fluororesin (such as PTFE) is used as the resin, it is possible to extrude a mixture of resin powder with a fluorolubricant as an auxiliary agent.

  In the inner layer covering body forming step, the inner layer covering body 51 may be formed by dip molding, not by extrusion molding. If the method by dip molding is outlined, first, in a container 200 as shown in FIG. 5, a solution R in which a resin as a material is dissolved in a solvent or a dispersion R in which a dispersion R is dispersed in a diluent is contained. Supply roll on which the core material W is wound and held via a flexible valve body 201 through which the core material W (here, the core wire 40) can be inserted while maintaining liquid tightness. The core material W is supplied from 202, and the core material W is inserted into the container 200 from below. Then, after the core material W is dipped (immersed) in the solution R or dispersion R in the container 200, the core 200 is pulled out above the container 200. As a result, the solution R or dispersion R is adhered to the outer peripheral surface of the core material W, and the solution R or dispersion R adhered to the core material W is heated and dried with hot air, a heater, etc. When the dispersion R is used, the inner layer covering 51 is formed by further sintering. The core material W coated with the material is wound around the collection roll 203 and collected after the coated material is solidified. As the solvent and diluent, those usually used can be applied. By changing the pulling speed from the container 200, the film thickness of the solution R or the dispersion R attached to the core material W can be arbitrarily changed, and the thickness of the inner layer covering 51 can be arbitrarily changed. The film thickness is determined by the interaction of the density, surface tension, viscosity, gravity and pulling speed of the solution R or dispersion R. When the pulling speed from the container 200 is decreased, the solution R attached to the core W is reduced. Alternatively, the film thickness of the dispersion R can be increased, and when the pulling rate is increased, the film thickness of the solution R or the dispersion R attached to the core material W can be decreased. For example, the film thickness of the part corresponding to the small diameter part 42 can be made thinner than the large diameter part 41, and the film thickness of the part corresponding to the transition part 43 can be gradually changed.

  Also, if the viscosity of the solution R or dispersion R is high, the coating thickness tends to be non-uniform, so the viscosity is set low enough to make the coating film thickness uniform, and dip molding is repeated multiple times. Thus, the coating thickness can be gradually increased, and the coating thickness can be controlled with high accuracy. When the dip molding is repeatedly performed, the recovery roll 203 from which the core material W coated with the material is recovered can be moved below the container 200 to be the supply roll 202, and the dip molding can be performed again. When the dip molding is repeated, it is preferable to dry and sinter the solution R or the dispersion R by heating with hot air or a heater every time.

  Further, when the dip molding is repeated a plurality of times, it is preferable that the dip molding is performed at least once in the opposite direction, rather than the dip molding by pulling up in the same direction of the core wire 40, more preferably once. It is preferable to perform dip molding while changing the direction one by one. By dipping from the opposite direction at least once, the film thickness can be made uniform by suppressing the unevenness of the film thickness depending on the pulling direction. The thickness deviation can be suppressed to the maximum and the film thickness can be made more uniform. In particular, in the core wire 40 whose outer diameter changes, the thickness 40 depending on the pulling direction is likely to occur in the portion where the outer diameter changes, so the core wire 40 in which the large diameter portion 41 and the small diameter portion 42 are formed. When the dip molding is performed, the dip molding is performed at least once from the opposite direction, so that a high effect can be achieved in making the film thickness uniform.

  In addition, although it can dry and sinter for every step of dip forming, it can also be dried and sintered after dip forming continuously several times without drying and sintering. Thus, the thickness in a desired part can be finely set by carrying out the dip molding continuously several times without drying and sintering.

  Further, when the dip molding is repeatedly performed, the number of repetitions can be changed according to the portion of the core wire 40. As an example of a method for this purpose, the portion where the number of repetitions is to be increased is pulled up, the solution R or dispersion R coated on the portion is dried and sintered, and then the core wire 40 that has moved upward is moved downward. And the part where the number of repetitions is to be increased is immersed in the solution R or the dispersion R. Thereafter, the core wire 40 is again moved upward, and the part where the number of repetitions is desired to be increased is again pulled up, so that the solution R or the dispersion R can be further coated. By repeating this, dip molding can be performed a desired number of repetitions according to the site. In this way, the number of repetitions of dip molding can be set as appropriate according to the site while switching the moving direction of the core wire 40. Therefore, for example, the number of repetitions of dip molding can be set so that transition portion> large diameter portion> small diameter portion or large diameter portion> transition portion> small diameter portion. A> B means that the number of repetitions in A is larger than the number of repetitions in B. Of these, it is preferable to perform dip molding so that the number of repetitions is maximized at the transition portion, because the thickness at the transition portion can be variably changed. Even in this method, drying and sintering can be performed for each step of dip molding, but drying and sintering may be performed after dip molding multiple times in succession without drying and sintering. .

  In addition, the core 40 is not moved, but the depth is changed by changing the amount H of the solution R or dispersion R shown in FIG. (Downward) can also be adjusted.

  In addition, the core material W is lifted from the container 200 while being rotated about the axis of the core material W, so that centrifugal force is applied to the solution R or dispersion R coated on the core material W to be coated. Can be arbitrarily changed. That is, the higher the rotational speed of the core material W, the greater the centrifugal force that acts, so that the film thickness of the solution R or dispersion R coated on the core material W can be reduced. The slower the centrifugal force acting, the more the film thickness of the solution R or dispersion R coated on the core material W can be increased. For example, by increasing the rotational speed at the time of pulling up the small diameter portion 42 rather than at the time of pulling up the large diameter portion 41, the film thickness covered by the small diameter portion 42 is changed to the film thickness covered by the large diameter portion 41. Can be made thinner. And when pulling up the transition part 43, the film thickness in the transition part 43 is changed smoothly and incline between the large diameter part 41 and the small diameter part 42 by changing the rotational speed of the core wire 40 gradually. be able to. Thereby, the distal end side of the manufactured catheter tube 10 can be made more flexible than the proximal end side. In addition, the larger the outer diameter of the core wire 40, the greater the centrifugal force that acts. Therefore, in order to make the film thickness of the solution R or dispersion R to be coated constant, the rotational speed is adjusted at the portion where the outer diameter changes. It is also possible to do.

  In the present embodiment, since the core material W is supplied from the supply roll 202 and is recovered by the recovery roll 203, the supply roll 202 and the recovery roll 203 can be rotated about the axis of the core material W in the container 200. However, the configuration of the apparatus is not limited as long as the core material W in the container 200 can be rotated.

  Further, when the core material W is pulled up from the container 200 while rotating, if a mixture of particles, fibers, and the like is mixed in the solution R or the dispersion R, the mixture can be oriented.

  When the dip forming is repeated a plurality of times while rotating, it is preferable to perform the dip forming while rotating the core wire 40 in the same direction each time instead of rotating at least once. It is preferable to perform dip molding while reversing the direction. By performing dip molding while rotating in reverse at least once, the film thickness can be made uniform by suppressing the deviation of film thickness depending on the rotation direction, and by rotating the rotation direction by changing the rotation direction one by one. The film thickness deviation depending on the thickness can be suppressed to the maximum, and the film thickness can be made more uniform.

  When it is desired to reduce the film thickness of the solution R or the dispersion R coated on the core material W, it is necessary to slow the pulling speed if it is controlled by the pulling speed. If it is controlled by speed, it can be adjusted by increasing the rotational speed without slowing the pulling speed, so that the manufacturing time can be shortened.

  Thus, the viscosity of the solution R or the dispersion R, the pulling speed, the pulling direction, the pulling site, the liquid amount of the solution R or the dispersion R (depth in the container 200), the number of repetitions of dip molding, the rotation speed, and By adjusting the rotation direction, the coating thickness and manufacturing time of the inner layer covering 51 to be coated can be controlled with high accuracy.

  In addition, if the inner layer covering 51 can be dip-molded, the container 200 does not have to be as described above. For example, the core material W is not inserted through the bottom of the container 200 but from above the container. May be dipped (immersed) in the solution R or the dispersion R, and the core material W may be curved and pulled up again. Further, after the solution R or the dispersion R is attached to the outer peripheral surface of the core material W, the amount of the solution R or the dispersion R to be attached is regulated by passing through a die (not shown) having a predetermined inner diameter. Thus, the outer diameter of the inner layer covering 51 can be adjusted. Further, if the core material W is directly received from the previous process and the core material W coated with the material is directly transferred to the subsequent process, the supply roll 202 and the recovery roll 203 around which the core material W is wound are not provided. May be.

  Further, the method for forming the inner layer covering 51 in the inner layer covering forming step is not limited to extrusion molding or dip molding. For example, a solution in which a resin is dissolved in a solvent or a dispersion in which a dispersion is dispersed in a diluent is sprayed. (Spray), application, printing, etc., after attaching to the core wire 40, the solution or dispersion attached to the core wire 40 is heated and dried with hot air or a heater, and depending on the material, it may be sintered. The inner layer covering 51 may be formed.

  After the inner layer covering body forming step, as shown in FIG. 3C, the reinforcing body 52 is formed so as to cover at least a part on the inner layer covering body 51 (reinforcing body forming step).

  The reinforcing body 52 is formed on the inner layer covering body 51 by continuously winding a strand with a braid having a predetermined interstitial distance. The reinforcing body 52 may be wound with strands while changing the winding direction, such as horizontal winding in the same direction, right-hand winding, left-hand winding, etc., and the winding pitch, interstitial distance, inclination angle with respect to the circumferential direction, etc. The configuration may be changed, and the configuration is not particularly limited.

  As the strands used for the reinforcing body 52, metal wires such as platinum (Pt) / tungsten (W), resin fibers, carbon fibers, glass fibers and the like can be applied, or a plurality of these strands may be used in combination. .

  After the reinforcing body forming step, as shown in FIG. 3D, the radiopaque marker 19 is arranged on the reinforcing body 52 (marker arranging step). The marker 19 is arranged by winding a wire formed of a material containing an X-ray opaque material from a radially outer side of the core wire 40 around a portion corresponding to the small diameter portion 42. Thus, by arranging the marker 19 from the outside in the radial direction of the core wire 40, even if the target to which the marker 19 is attached has a continuous shape before being cut, it can be easily arranged. As the material of the marker 19, a material in which an X-ray contrast agent such as metal powder of platinum, gold, silver, tungsten, or an alloy thereof, barium sulfate, bismuth oxide, or a coupling compound thereof is kneaded can be applied. The outer diameter of the wire constituting the marker 19 is, for example, about 30 to 50 μm, but is not particularly limited as long as it has radiopacity.

  In the present embodiment, only one marker 19 is provided in a portion corresponding to the small diameter portion 42, but a plurality of markers 19 may be provided in the small diameter portion 42. In addition, the marker 19 may not be provided in the portion corresponding to the small diameter portion 42, and one or a plurality of markers may be provided in the portion corresponding to the large diameter portion 41. Moreover, a marker may be provided on both the small diameter portion 42 and the large diameter portion 41. By providing a plurality of markers, not only can the position be observed from outside the body by X-rays, but also the length can be measured using the markers as scales.

  After the marker placement step, a tubular continuous body 60 composed of the inner layer covering body 51, the reinforcing body 52 and the marker 19 is obtained on the core wire 40. The configuration including the core wire 40 in the tubular continuous body 60 is referred to as a catheter tube continuous body 65.

  After the marker placement step, as shown in FIG. 3E, the catheter tube continuous body 65 having the core wire 40 and the tubular continuous body 60 is cut at a predetermined position (cutting step). The continuous body 65 of the catheter tube includes a first cutting portion 63 that is close to one end of the large diameter portion 41 and a first thin portion 42 that is close to the first cutting portion 63 across the transition portion 43. It cut | disconnects with the 2 cutting part 64. FIG. Thereby, the single tube 61 from which the large diameter part 41 is cut long and the surplus tube 62 from which the large diameter part 41 is cut short are formed. The single tube 61 corresponds to one catheter tube 10 and is an intermediate body before reaching the catheter tube 10. The surplus tube 62 is removed as an unnecessary portion. As an example, in the single tube 61, the length of the portion corresponding to the large diameter portion 41 of the core wire 40 is 1600 mm, and the length of the portion corresponding to the small diameter portion 42 of the core wire 40 is 100 mm. In addition, the large diameter part 41 and the small diameter part 42 of the core wire 40 can be set long so that the surplus tube 62 has the same shape as the single tube 61, and the surplus tube 62 can also be used as the single tube 61.

  In the cutting step, for example, a cutting blade is used to cut with a shearing machine or the like, but any cutting method may be used as long as it can cut the core wire 40 and the covering (the inner layer covering 51 and the reinforcing body 52). The cutting step may be performed at any stage after the marker placement step, for example, may be performed after the outer layer covering body forming step, or after the hydrophilic covering body forming step. May be.

  After the cutting step, as shown in FIG. 3 (F), the outer layer covering 53 is formed on the outer surface of the single tube 61 by covering at least part of the marker 19 and the reinforcing member 52 (outer layer covering). Forming step). As an example, the outer diameter of the outer layer covering 53 in a portion corresponding to the large diameter portion 41 is 0.8 mm to 1.1 mm, and the outer diameter of the outer layer covering 53 in a portion corresponding to the small diameter portion 42 is 0.6 mm to 1. 0.0 mm. The outer diameter of the outer layer covering 53 at the portion corresponding to the transition portion 43 gradually changes and is 0.6 mm to 1.1 mm. The dimensions are not limited to this.

  The material of the outer layer covering 53 is, for example, polyolefin (for example, polyethylene, polypropylene, polybutene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, ionomer, or a mixture of two or more thereof), polyvinyl chloride, etc. A thermoplastic resin such as a polyamide, a polyester elastomer, a polyamide elastomer, a polyurethane, a polyurethane elastomer, polyimide, a fluororesin, or a mixture thereof, or a thermosetting resin such as an epoxy resin can be applied. The outer layer covering 53 may be mixed with a radiopaque material.

  In the outer layer covering forming process, first, as shown in FIG. 6A, a plurality of (in the present embodiment) are provided in the axial direction on the radially outer side of the single tube 61 so as to form one cylindrical shape as a whole. Three covering members 70A, 70B, and 70C are covered. The covering members 70 </ b> A, 70 </ b> B, 70 </ b> C are materials that become the outer layer covering 53. The covering members 70 </ b> A, 70 </ b> B, 70 </ b> C have an inner diameter larger than the outer diameter of the single tube 61, and can be easily put on the single tube 61. By forming the outer layer covering 53 using the plurality of covering members 70A, 70B, and 70C, it becomes possible to easily vary the respective materials, shapes, and characteristics, and it is possible to manufacture various catheter tubes 10. Become.

  Next, as shown in FIG. 6 (B), the shape memorized by heating the coating members 70A, 70B, 70C on the radially outer side so as to cover the coating members 70A, 70B, 70C. A shrinkable heat shrinkable tube 71 is placed. The heat shrinkable tube 71 is, for example, a fluorine resin.

  Next, as shown in FIG. 6C, the heat-shrinkable tube 71 is shrunk while being heated by a heat source 75 such as hot air or a heater to soften or melt the covering members 70A, 70B, 70C. The covering members 70 </ b> A, 70 </ b> B, 70 </ b> C are pressed by the shrinkage force 71, and the covering members 70 </ b> A, 70 </ b> B, 70 </ b> C are brought into close contact with the outer periphery of the reinforcing body 52 and the inner layer covering body 51. Further, a twisting force is applied to the heat shrinkable tube 71 around the axis of the core wire 40. A plurality of heat sources 75 are provided in the circumferential direction around the axis of the core wire 40, and move along the axis of the core wire 40 while rotating these around the axis of the core wire 40. Thereby, the shrinkage | contraction of the heat contraction tube 71 generate | occur | produces so that a spiral may be drawn, and it can generate a twisting force. Thereby, a compressive force and a shearing force act on the boundary portion between the adjacent covering member 70A and the covering member 70B and the boundary portion between the adjacent covering member 70B and the covering member 70C, so that the respective materials are melted. Bonding is promoted while the compatible state is promoted. Thereby, between the adjacent covering member 70A and the covering member 70B and between the covering member 70B and the covering member 70C are well coupled with a strong coupling force. The torsional force also exerts a compressive force and a shearing force on the joint surfaces of the covering members 70A, 70B, and 70C with the reinforcing body 52 and the inner layer covering body 51, thereby enhancing the binding force thereto.

  As shown in FIG. 6D, the heat-shrinkable tube 71 that has been heat-shrinked is formed after the covering members 70A, 70B, and 70C are formed as the outer layer covering 53 around the outer periphery of the reinforcing body 52 and the inner layer covering 51. It is.

  In addition, as a method of applying a twisting force to the covering members 70A, 70B, and 70C, the heat source is fixedly provided instead of being rotated and the single tube 61 covered with the heat shrinkable tube 71 and the covering member 70A are provided. , 70B, 70C may be rotated relative to the heat source. Further, the heat shrink tube 71 may be twisted so as to be gripped and narrowed by hand, or a mechanism capable of realizing such an operation may be provided.

  In addition, you may remove a part of reinforcement body 52 before an outer layer covering body formation process. For example, in order to ensure the flexibility of the tube distal end portion 12 of the catheter tube 10, a portion on the distal end side of the reinforcing body 52 corresponding to the small diameter portion 42 can be removed.

  After the outer layer covering forming step, as shown in FIG. 3G, a part of the covering at both ends of the core wire 40 cut in the cutting step is removed, and a part of both ends of the core wire 40 is exposed. To the drawing machine and the whole core wire 40 is drawn (core wire drawing step). Thereafter, as shown in FIG. 3H, the core wire 40 is pulled out from the large diameter portion 41 side (core wire removing step). In addition, after extending | stretching until the core wire 40 fractures | ruptures in the small diameter part 42 with an extending | stretching machine, you may pull out the broken core wire 40 from the large diameter part 41 side and the both sides of the small diameter part 42. Further, the core wire 40 may be stretched and pulled out after the cutting step and before the outer layer covering body forming step.

  After the core wire removing step, as shown in FIG. 3 (I), a hydrophilic polymer substance (on the part corresponding to the small diameter part 42 and the part corresponding to the large diameter part 41 of the outer layer covering 53) is formed. A hydrophilic coating 54 is formed by coating the hydrophilic material (hydrophilic coating forming step). Thereby, the catheter tube 10 is completed. The hydrophilic covering 54 (hydrophilic layer 18) on the outer surface of the catheter tube 10 exhibits lubricity when in contact with a liquid such as blood or physiological saline, and the friction resistance of the catheter tube 10 is reduced. Further, the slidability is further improved. As a result, the operability of insertion is further improved, and the pushability, followability, kink resistance and safety are further improved.

  Further, when inserting the catheter tube 10 into a blood vessel, it is necessary to operate the catheter tube 10 by holding the proximal end side of the catheter tube 10 in a hand. For this reason, if the base end side of the catheter tube 10 slips when held by hand, the operability is lowered, which is not preferable. Therefore, the range in which the hydrophilic polymer substance in the longitudinal direction of the catheter tube 10 is applied is a predetermined length (for example, about 150 to 500 mm) from the proximal end of the catheter tube 10 toward the distal end. It is preferable to impart a hydrophilic polymer substance to the region excluding.

  Examples of the hydrophilic polymer substance include the following natural or synthetic polymer substances or derivatives thereof. In particular, cellulosic polymer materials (eg, hydroxypropyl cellulose), polyethylene oxide polymer materials (polyethylene glycol), maleic anhydride polymer materials (eg, maleic anhydride such as methyl vinyl ether maleic anhydride copolymer) Copolymers), acrylamide polymer substances (for example, polyacrylamide), and water-soluble nylon (for example, AQ-nylon P-70 manufactured by Toray Industries, Inc.) are preferable because a low friction coefficient can be stably obtained. Among these, a maleic anhydride polymer material is more preferably used. Further, the derivative of the polymer substance is not limited to a water-soluble derivative, and there is no particular limitation as long as the polymer substance has a basic configuration, and even if it is insolubilized, the molecular chain has a degree of freedom. As long as it has water and contains water.

  In order to fix such a hydrophilic polymer substance to the outer surface of the catheter tube 10, it is covalently bonded to a reactive functional group present or introduced in the outer layer covering 53 or on the surface of the outer layer covering 53. It is preferable to carry out. Thereby, a continuous lubricating surface can be obtained.

  The reactive functional group present in or introduced into the outer layer covering 53 or on the surface thereof may be any one that reacts with the hydrophilic polymer substance and is fixed by being bonded or cross-linked, such as a diazonium group. , Azide group, isocyanate group, acid chloride group, acid anhydride group, imino carbonate group, amino group, carboxyl group, epoxy group, hydroxyl group, aldehyde group, and the like. Among these, as the reactive functional group, an isocyanate group, an amino group, an aldehyde group, and an epoxy group are more preferable.

  The hydrophilic covering forming step may be performed after the outer layer covering forming step and before the core wire stretching step or the core wire removing step. The hydrophilic covering forming step may be performed after the hub 20 and the kink protector 30 are connected to the manufactured catheter tube 10.

  As described above, the manufacturing method of the catheter tube according to the present embodiment is provided with a plurality of resin coating members 70A that are provided in the axial direction on the radially outer side of the core wire 40 to form one cylindrical shape as a whole. A plurality of covering members 70A, 70B are applied by covering 70B, 70C, heating the covering members 70A, 70B, 70C while pressing them inward in the radial direction and applying a torsional force about the axis of the core wire 40. , 70C and bonding to form an outer layer covering 53 (covering body) to form an outer layer covering body forming step (covering body forming step), and a single tube obtained on the core 40 after the outer layer covering body forming step A core wire removing step of removing the core wire 41 from 61. In this way, the resin-made 70A, 70B, and 70C arranged on the outer side in the radial direction of the core wire 40 are heated while pressing toward the inner side in the radial direction, and a torsional force is applied to the plurality of covering members 70A and 70B. , 70C while being coupled, the catheter tube 10 can be manufactured while satisfactorily coupling the covering members 70A, 70B, 70C aligned in the axial direction.

  As a method of manufacturing a catheter tube, a hot stretching process is generally performed in which a tube is subjected to a hot stretching process to reduce the inner and outer diameters from the proximal side to the distal end side. When the intermediate stretching process is performed, the residual strain due to the hot stretching process is affected during hot melt processing such as when attaching a soft tip or contrast marker, and the inner and outer diameters in the vicinity of the melted part increase, resulting in poor dimensional accuracy. In particular, there is a problem such as a decrease in yield. On the other hand, according to the manufacturing method according to the present embodiment, since the hot stretching process is not performed, there is no distortion due to stretching, the workability is improved, and as a result, the cost is reduced. In addition, since the winding pitch of the reinforcing body 52 (interstitial distance in the case of braiding) does not increase due to stretching, the tip portion is excellent in flexibility and kink resistance.

  Further, in the outer layer covering forming process, the heat shrinkable tube 71 is covered on the radially outer side of the covering members 70A, 70B, 70C, and the heat shrinkable tube 71 is twisted around the axis of the core wire 40 while heating the heat shrinkable tube 71. Since a force is applied, a twisting force can be easily applied to the heat shrinkable tube 71 while applying a pressing force by using the contraction force of the heat shrinkable tube 71 that contracts when heated.

  Moreover, since the core wire 40 is formed with the large diameter portion 41 and the small diameter portion 42 having different outer diameters in advance, the catheter tube 10 having different diameters on the distal end side and the proximal end side can be efficiently manufactured on the core wire 40. .

  Moreover, since it has the reinforcement body formation process which forms the reinforcement body 52 which consists of a wire material in the radial inside rather than the outer layer coating body 53 (covering body) before an outer layer covering body formation process (covering body formation process), it manufactures The tube 10 for catheter to be used can be reinforced according to a site | part, and pushing property and kink resistance can be improved.

  Further, before the outer layer covering body forming step (covering body forming step), the inner layer covering body 51 (other covering body) is formed by coating the resin on the radially inner side with respect to the outer layer covering body 53 (covering body). Since the inner layer covering body forming step (another covering body forming step) is provided, the multi-layer catheter tube 10 having a plurality of layers can be efficiently manufactured while using the core wire 40.

  Note that the present invention is not limited to the above-described embodiments, and various modifications can be made by those skilled in the art within the technical idea of the present invention.

  For example, in this embodiment, the outer layer covering body forming step of forming the outer layer covering body 53 after the cutting step (FIG. 3 (E)) of cutting the tubular continuous body 60 obtained on the core wire 40 and cutting the single tube 61. (FIG. 3F) is performed, but the outer layer covering body forming step may be performed before the cutting step. In this case, for example, an apparatus 300 as shown in FIG. 7 can be used. The apparatus 300 uses a continuous body 65 (see FIG. 3D) of a catheter tube in which a core wire 40 is coated with an inner layer covering body 51 and a reinforcing body 52 as a core material W. An outer layer covering 53 is formed for each unit structure including the diameter portion 41 and one small diameter portion 42. The apparatus 300 includes a plurality of upper molds 301A, 301B, and 301C (301A, 301B, and 301C are collectively referred to as 301) for coating the outer layer covering 53 on the core W, and upper molds 301A, 301B, and 301C. When the lower molds 302A, 302B, and 302C (302A, 302B, and 302C are collectively referred to as 302), the core material W is wound and held, and the core material W is supplied between the upper mold 301 and the lower mold 302. Supply roll 303, and a collection roll 304 that collects the core material W coated with the outer layer covering 53. The upper mold 301 and the lower mold 302 are provided with heating means such as a heater. The upper die 301A and the lower die 302A are rotatable around the axis of the core wire 40 in a state where the die is clamped. Further, the upper die 301C and the lower die 302C are also rotatable around the axis of the core wire 40 in a clamped state.

  A plurality of materials for the outer layer covering body 53 are provided in the axial direction and are also provided in the circumferential direction so as to be supplied as resin covering members 310A to 310F that form a single cylindrical shape as a whole. The covering members 310A and 310B are arranged so as to sandwich the core material W between the upper mold 301A and the lower mold 302A, and two form a single cylindrical shape. The covering members 310C and 310D are arranged so as to sandwich the core material W between the upper mold 301B and the lower mold 302B, and two form a single cylindrical shape. The covering members 310E and 310F are arranged so as to sandwich the core material W between the upper mold 301C and the lower mold 302C, and two form a single cylindrical shape. In this way, the covering members 310A to 310F are arranged so as to surround the core material W that is continuously supplied without any breaks by providing a plurality of covering members 310A to 310F arranged in the circumferential direction. It is possible. In addition, the number provided in the circumferential direction of the covering member may be three or more. The number of covering members arranged in the axial direction is three in the present embodiment, but may be two or four or more.

  When covering the core material W with the outer layer covering 53, first, the core material W is positioned at a predetermined position, and the covering member 310 </ b> A surrounds the core material W between the upper mold 301 and the lower mold 302. Place ~ 310F. Next, as shown in FIG. 8, the upper mold 301 and the lower mold 302 are clamped in a heated state. Accordingly, the covering members 310A to 310F are pressed by the upper mold 301 and the lower mold 302 while the covering members 310A to 310F are softened or melted, and the covering members 310A to 310F are pressed against the reinforcing body 52 and the inner layer covering body 51. Adhere to the outside. Further, the upper mold 301A and the lower mold 302A are rotated around the axis of the core wire 40, and the upper mold 301C and the lower mold 302C are rotated in the opposite direction to the upper mold 301A and the lower mold 302A. Thereby, a compressive force and a shearing force act on the boundary portion between the adjacent covering members 310A and 310B and the covering members 310C and 310D and the boundary portion between the adjacent covering members 310C and 310D and the covering members 310E and 310F. Thus, the materials are bonded together while promoting a compatible state in which the materials melt. As a result, the plurality of covering members 310A to 310F are well coupled with a strong coupling force. In addition, the torsional force exerts a compressive force and a shearing force at the joint portion between the reinforcing member 52 and the inner layer covering member 51 of the covering members 310 </ b> A to 310 </ b> F, thereby enhancing the binding force thereto. Thus, the outer covering member 53 is formed so as to cover the reinforcing member 52 and the inner covering member 51 while the covering members 310 </ b> A to 310 </ b> F are coupled to each other with a strong binding force.

  Thereafter, the upper die 301A and the lower die 302A are separated from each other, and the core material W coated with the outer layer covering 53 is collected on the collection roll 304 while the core material W is supplied from the supply roll 303 that supplies the core material W. Then, the above-described steps are repeated to coat the next outer layer covering 53. Thereafter, the structure obtained on the core wire 40 is cut together with the core wire 40 (cutting step), the core wire is stretched (core wire drawing step), the core wire 40 is pulled out from the large diameter portion 41 side (core wire removing step), and the catheter tube 10 is completed. Thus, even if the core wire 40 in which the large-diameter portion 41 and the small-diameter portion 42 having different outer diameters are continuously formed at a predetermined interval is not cut, a plurality of core wires 40 are arranged in the circumferential direction as a whole. By using the covering members 310A to 310F constituting the shape, the covering members 310A to 310F are heated while pressing the inner side in the radial direction, and a torsional force is applied, so that a plurality of the covering members 310A to 310F are applied. It can be coated while bonded. Then, in the cutting step, the structure on the core wire 40 is cut at predetermined positions of the large-diameter portion 41 and the small-diameter portion 42 to cut out the plurality of single tubes 61, whereby the tube base end portion 11 and the tube distal end portion 12 are cut. Thus, the catheter tube 10 having different inner and outer diameters can be efficiently manufactured while being formed on the continuous core wire 40. Note that the covering member may not be provided in a plurality in the circumferential direction as long as it covers the core material W. For example, the covering member has a C-shaped cross section in which a slit extending in the axial direction is formed. 40 may be applied.

  In this embodiment, the outer layer covering 53 is formed by applying heat, pressing force, and twisting force. However, the inner layer covering may be formed by applying heat, pressing force, and twisting force. . Further, the present manufacturing method may be applied to the manufacture of a single-layer catheter tube rather than a multilayer structure.

  The core wire may be formed with a constant outer diameter without including the large diameter portion 41 and the small diameter portion 42.

  In the present embodiment, the marker 19 is disposed on the reinforcing body 52, but may be disposed between the inner layer covering body 51 and the reinforcing body 52, or may be disposed on the outer layer covering body 53. May be.

  Further, the reinforcing body 52 may not be provided between the inner layer covering body 51 and the outer layer covering body 53, and may be provided on the outer side in the radial direction of the outer layer covering body 53, for example. Further, each of the reinforcing body 52 and the hydrophilic covering body 54 may not be provided.

  Further, at least one of the inner layer covering 51 and the outer layer covering 53 may be irradiated with an electron beam or gamma ray to crosslink the material to increase the hardness. Further, at least one of the inner layer covering body 51 and the outer layer covering body 53 may be subjected to a softening process for reducing the hardness using an acid or an alkali.

  Further, a transition portion 83 between the large-diameter portion 81 and the small-diameter portion 82 may be provided only on one end side of the large-diameter portion 81 as in a core wire 80 as a modified example shown in FIG. Thereby, the length of the surplus tube (see the surplus tube 62 in FIG. 3E) to be removed after cutting is shortened, and the cost can be reduced and the manufacturing area can be saved.

  Further, at least a part of the shape of the outer peripheral surface of the transition portion 93 in the cross section along the axis of the core wire 90 may be formed as a curve, like a core wire 90 as another modification shown in FIG. Thereby, the rigidity of the manufactured catheter tube changes smoothly and in an inclined manner along the axis, local bending is suppressed, and a catheter tube excellent in pushability and kink resistance can be manufactured. In FIG. 10, the inclination angle X of the outer peripheral surface of the transition portion 93 in the cross section along the axis of the core wire 90 gradually increases from the small diameter portion 92 toward the large diameter portion 91. It becomes the maximum, and gradually becomes smaller as it gets closer to the large-diameter portion 91. By adopting such a shape, the rigidity along the axis between the large-diameter portion 91 and the small-diameter portion 92 can be changed more smoothly and in an inclined manner, and the catheter is more excellent in pushability and kink resistance. Tubes can be manufactured.

  The cross-sectional shape of the catheter tube 10 in the cross section orthogonal to the axis may not be circular, and may be, for example, elliptical. Further, the lumen 14 in the catheter tube 10 may not have a circular cross-sectional shape in the axial orthogonal cross section, and may be, for example, an elliptical shape or a semicircular shape. The catheter tube 10 may be provided with a plurality of lumens.

1 catheter,
10 Catheter tube,
19,110 markers,
40, 80, 90 core wires,
41, 81, 91 Large diameter part,
42, 82, 92 Small diameter part,
43, 83, 93 Transition section,
51 Inner layer covering (covering body),
52 reinforcements,
53 outer layer covering,
54 hydrophilic covering,
60 tubular continuum,
61 Single tube,
63 1st cutting part,
64 second cutting part,
65 A continuum of catheter tubes,
70A-70C, 310A-310F Covering member,
D1 Outer diameter of the large diameter part,
D2 Outer diameter of small diameter part,
X Tilt angle.

Claims (6)

A plurality of resin products that are provided in the axial direction on the radially outer side of the core wire so as to form a single cylindrical shape, or that are provided in the axial direction and that are provided in the circumferential direction to form a single cylindrical shape as a whole. The covering member is covered, heated while pressing the covering member inward in the radial direction, and a torsional force is applied about the axis of the core wire to cover the plurality of covering members together. A covering forming step for forming a covering,
A method of manufacturing a catheter tube, comprising: a core wire removing step of removing the core wire from a single tube obtained on the core wire after the covering body forming step.   The said covering body formation process WHEREIN: A heat shrinkable tube is covered on the radial direction outer side of the said covering member, A twisting force is made to act on the said heat shrinkable tube centering on the axis line of the said core wire, heating the said heat shrinkable tube. 2. A method for producing a catheter tube according to 1.   The said core wire is a manufacturing method of the tube for catheters of Claim 1 or 2 with which the large diameter part and thin diameter part from which an outer diameter differs are formed previously. The core wire is continuously formed with a large-diameter portion and a small-diameter portion having different outer diameters at predetermined intervals,
4. The catheter according to claim 1, wherein, in the cutting step, the tubular continuous body is cut at predetermined positions of a large-diameter portion and a small-diameter portion of the core wire to cut out a plurality of the single tubes. Tube manufacturing method.   5. The reinforcing body forming step according to claim 1, further comprising a reinforcing body forming step of forming a reinforcing body made of a wire material on a radially inner side or an outer side than the covering body before or after the covering body forming step. A method for producing a catheter tube.   6. The method according to claim 1, further comprising another covering body forming step of forming another covering body by coating a resin inside or outside in the radial direction from the covering body before or after the covering body forming step. The manufacturing method of the tube for catheters of Claim 1.

Images