JP6278562B2 - Method for producing medical drain tube, crosshead die and crosshead extruder - Google Patents

Description

  The present invention relates to a method for manufacturing a medical drain tube, and a crosshead die and a crosshead extruder used in the manufacturing method. More specifically, the medical use has a uniform outer diameter of at least a transition portion and a drain portion. The present invention relates to a method for manufacturing a medical drain tube capable of forming a drain tube with good workability, and a crosshead die and a crosshead type extruder used in this manufacturing method.

For excretion of wounds after surgery, blood accumulated inside, body fluid (exudate, etc.), or urine etc. (referred to as body fluid in the present invention) during treatment in an intensive care unit, etc. A drain tube is used.
There are various types of medical drain tubes, but in recent years, a multi-slit type has attracted attention. The multi-slit type medical drain tube is difficult to block even when bent, can maintain the suction effect, is multi-functional and can be used in various situations, has a short-term (per unit time) discharge capacity, and This is because it has characteristics such as close / active drainage and excellent portability.

  Such a multi-slit type medical drain tube has a drain portion on one end side of the tube having at least two open liquid passages (called open liquid passages) that open to the outer peripheral surface along the axial direction. A tubular portion having a shaft hole is provided on the other end side of the tube. As such a multi-slit type medical drain tube, for example, one in which a drain portion and a tubular portion are connected by a flexible tubular collar can be cited (see, for example, FIG. 6 of Patent Document 1).

  In this medical drain tube, the outer diameter in the vicinity of the connecting portion between the drain portion and the tubular portion is increased by the tubular collar, and the flexibility in the vicinity of the connecting portion is lowered and the strength is increased. Since the medical drain tube is temporarily embedded and indwelled in the patient's body and finally removed from the body, if there is a connection as described above, the surgical operation at the time of implantation and removal This complicates the burden on patients. Therefore, development of the medical drain tube which does not have a connection part is desired.

  In response to this demand, a medical drain tube that does not have a connecting portion by extrusion molding has been proposed. For example, Patent Document 2 describes a die having a die mandrel capable of moving back and forth in the axial direction, and a medical drain tube formed by continuous extrusion using the die.

  In addition, as a medical drain tube having no connection portion, a die mechanism for manufacturing a medical drain tube in which the shape of the lumen changes in several stages has been proposed. For example, there is a die mechanism for variable cross-sectional shape extrusion that forms an inner cavity by a plurality of steps by moving an indie having a plurality of steps whose diameter is increased on the rear side in the longitudinal direction of a land portion or the like in a longitudinal direction. (Patent Document 3).

Japanese Examined Patent Publication No. 2-17185 U.S. Pat. No. 4,465,481 Japanese Patent No. 3418535

Here, since the medical drain tube is inserted into and removed from the patient's body and used as described above, it is desirable that the outer diameter thereof, at least the outer diameter of the portion inserted into the patient, be uniform (for example, , Patent Document 2, column 7, lines 48-52).
However, when a medical drain tube is extruded using the die described in Patent Document 2 and the die mechanism for variable cross-sectional shape extrusion described in Patent Document 3, the drain part, the tubular part, and the transition part have different sectional shapes. Therefore, the extrusion speed varies when these are extruded. When the extrusion speed fluctuates, if the extrusion amount of the molding material is adjusted in accordance with the fluctuating extrusion speed or the take-off speed is not adjusted, a difference in outer diameter due to fluctuation and difference in the extrusion speed occurs. As a result, a medical drain tube having a predetermined outer diameter cannot be molded, and the moldability may be poor. On the other hand, in order to eliminate the difference in outer diameter, adjusting the extrusion amount of the molding material or adjusting the take-off speed according to the varying extrusion speed is inferior to the molding workability and also to the uniformity of quality. It can also have an adverse effect.

  Therefore, the present invention provides a medical drain tube manufacturing method capable of forming a medical drain tube having a uniform outer diameter of at least the transition portion and the drain portion with good molding workability, and a crosshead die used in the manufacturing method and An object is to provide a cross-head type extruder.

  The present inventor has made various investigations in the medical drain tube extrusion molding method by paying attention to the volume of the flow path cavity in the variable die mechanism, and found that the flow rate change of the molding material and the molding material ballast based on this flow rate change. It has been found that a difference in outer diameter occurs in the molded product due to variation in the effect (also referred to as the Merlinton effect). Here, the flow rate of the molding material becomes slower due to the increase in volume of the flow path cavity during the transition from the drain part molding to the transition part molding, and during the transition from the transition part molding to the tube part molding. It fluctuates so that the volume of the volume decreases and becomes faster. Further, it has been found that the above-mentioned difference in outer diameter that occurs in the extrusion method becomes prominent when shifting from one to the other during drain portion molding and transition portion molding. Furthermore, if the member that forms the opening of the drain part is provided in the vicinity of the outlet of the crosshead die, preferably outside, the change in the volume of the channel cavity during the transition between the drain part molding and the transition part molding can be reduced. As a result, it has been found that the outer diameter difference between the drain portion and the transition portion can be eliminated without particularly adjusting the extrusion amount and take-up speed of the molding material. Based on these findings, the present inventor has further researched and made the present invention.

The object of the present invention has been achieved by the following means.
(1) A tubular portion having an axial hole, a drain portion having a plurality of open liquid passages having openings extending in the axial direction in a non-communication state by a support portion, and both end portions of the axial hole and the open liquid passage Cross of a crosshead type extruder for extruding a medical drain tube having a communicating lumen in a tubular wall in a non-communication state by a partition wall and having a transition portion connecting the tubular portion and the drain portion A head die,
An out die having a discharge port, an inner die disposed in the discharge port, embedded in an inner peripheral surface of the discharge port, or disposed on the discharge side surface of the out die so as to be movable forward and backward in the radial direction of the discharge port, A movable claw capable of forming the opening of the drain part,
The inner die is supported so as to be able to move forward and backward with respect to the discharge port, and the shaft hole together with the fixed inner die. A crosshead die having a movable inner die that can be formed.
(2) The crosshead die according to (1), wherein the movable inner die is supported so as to move forward and backward in the fixed inner die.
(3) The crosshead die according to (1) or (2), wherein the movable claw is attached to the discharge side surface by screwing.
(4) The fixed inner die has a front end portion in which a plurality of circular pillars having a fan-shaped cross section are arranged in a ring with a gap in the circumferential direction.
The crosshead die according to any one of (1) to (3), wherein the movable inner die has a tip portion corresponding to the gap of the fixed inner die.
(5) The crosshead die according to (4), wherein the tip end portion of the fixed inner die is formed by cutting a groove in a radial direction from the center of a solid cylindrical body.
(6) A crosshead type extruder comprising the crosshead die according to any one of (1) to (5).
(7) A tubular portion having an axial hole, a drain portion having a plurality of open liquid passages having openings extending in the axial direction in a non-communication state by a support portion, and both end portions of the axial hole and the open liquid passage A crosshead type medical drain tube comprising: a tubular portion and a transition portion for connecting the drain portion, each having a communicating lumen in a tubular wall in a non-communication state by a partition wall; A manufacturing method for manufacturing using an extruder,
A method for manufacturing a medical drain tube, wherein the movable inner die and the movable claw are respectively moved forward and backward in accordance with the tubular portion, the transition portion, and the drain portion.
(8) Disposing the movable inner die in the discharge port and retreating the movable claw radially to the outside of the discharge port to form the tubular portion;
Retreating the movable inner die from the discharge port, and forming the transition portion;
The method of manufacturing a medical drain tube according to (7), wherein the movable claw is advanced inward in the radial direction to the inside of the discharge port, and the drain portion is formed.
(9) retreating at least the movable inner die from the inside of the discharge port and advancing the movable claw radially inward to the inside of the discharge port, and forming the drain portion;
Retreating the movable claw radially to the outside of the discharge port, and forming the transition portion;
The method for manufacturing a medical drain tube according to (7), wherein the movable inner die is advanced into the discharge port to form the tubular portion.
(10) The method for producing a medical drain tube according to any one of (7) to (9), wherein a thermosetting silicone rubber composition is extruded.

The crosshead die of the present invention and the crosshead extruder of the present invention are provided with the inner die and the movable claw described above, and the volume change of the flow path cavity at the time of transition between the drain part molding and the transition part molding is measured. The extrusion speed when forming at least the drain part and the transition part can be kept substantially constant, and the difference in outer diameter between the drain part and the transition part can be eliminated.
In addition, the medical drain tube of the present invention is manufactured by moving the inner die and the movable claw in the crosshead type extruder of the present invention, and is a medical drain tube having a uniform outer diameter of at least the transition part and the drain part. Can be molded with good workability.

FIG. 1 is a partially enlarged schematic view in the vicinity of a crosshead die showing an example of a crosshead extruder of the present invention. FIG. 2 is a diagram showing an example of an inner die used in the crosshead die of the present invention. FIG. 3 is an explanatory view illustrating the arrangement state of the crosshead die in an example of the method for producing a medical drain tube of the present invention. FIG. 4 is a view showing an example of a medical drain tube manufactured by the method for manufacturing a medical drain tube of the present invention.

  The medical drain tube manufactured with the manufacturing method of the medical drain tube of this invention is demonstrated. The medical drain tube may be any tube in which the tubular portion, the transition portion, and the drain portion are connected in this order, and examples include those known in the art, for example, those described in Patent Document 2. Therefore, the shape and dimensions of the medical drain tube are not particularly limited, and are appropriately set according to the usage mode and standards. For example, the outer diameter can be set to 3.3 mm, 5.0 mm, 6.3 mm, 8.0 mm, or the like.

  The medical drain tube manufactured by the method for manufacturing a medical drain tube of the present invention has a uniform dimension, particularly an outer diameter, in the axial direction at least in the drain portion and the transition portion. Here, “the dimension is uniform” includes not only that the dimension is strictly uniform, but also that the dimension is constant within an allowable range in use. Preferably, the ratio of the outer diameter of the tubular part to the outer diameter of the transition part (outer diameter of the tubular part / outer diameter of the transition part × 100 (%)), and the ratio of the outer diameter of the drain part to the outer diameter of the transition part Each of (the outer diameter of the drain part / the outer diameter of the transition part × 100 (%)) is within a range of ± 2.5%, for example.

  Hereinafter, a preferable medical drain tube manufactured by the method for manufacturing a medical drain tube of the present invention will be briefly described.

As shown in FIG. 4, a suitable medical drain tube 41 is formed by integrally connecting a tubular portion 42, a transition portion 43, and a drain portion 44 in this order along the axial direction.
4A is a side view showing an example of the medical drain tube, FIG. 4B is a cross-sectional view showing a cross section of the tubular portion of the tube, and FIG. 4C is this tube. FIG. 4D is a cross-sectional view showing a cross section of the drain portion of the tube.

  The tubular portion 42 is normally not embedded or placed in the patient's body, but has a free end connected to a suction device or the like to transfer and discharge the collected body fluid. The tubular portion 42 only needs to have a normal tubular structure, and is a tubular body having an axial hole 51 along the axial direction. Therefore, the tubular portion 42 is formed by a tubular wall 52 having a ring-shaped cross section perpendicular to the axial direction.

The drain part 44 has a function of being embedded and indwelled in the patient's body, collecting body fluid, etc., and transferring it outside the body.
As shown in FIGS. 4A and 4D, the drain portion 44 has four open liquid passages 61 that extend in the axial direction in a non-communication state. Each of the opening liquid passages 61 has an opening (also referred to as a groove) 62 that opens along the axial direction on the outer peripheral surface. As described above, the drain portion 44 has four open liquid passages 61 each having the opening 62 extending in the axial direction.

  The drain portion 44 is formed by extending a cross-sectional shape, which will be described later, perpendicular to the axial direction over the axial direction. As shown in FIG. 4D, this cross-sectional shape is adjacent to four support portions 63 whose one ends are connected substantially vertically so that they have the same central angle, and from the other ends (tips) of the support portions 63. Each of the two support portions 63 has a projecting portion 64 that projects in an arc shape as a whole. Thus, the support part 63 and the protrusion part 64 are united, and are substantially T-shaped. The opening liquid passage 61 is formed in a substantially fan shape opened by two supporting portions 63 and two projecting portions 64 adjacent to each other in the circumferential direction, and the opening 62 is formed in the space of the end portions of the two projecting portions 64. Has been. Accordingly, the four open liquid passages 61 are not in communication with each other by the support portion 63. Since the support part 63 and the protrusion part 64 are extended in an axial direction, it is also called a support wall and a protrusion wall.

  The transition part 43 connects the tubular part 42 and the drain part 44, and in some cases, a part of the transition part 43 on the drain part 44 side is embedded and placed in the patient's body. As described above, the transition portion 43 is a connection portion that connects the tubular portion 42 and the drain portion 44 so that the shaft hole 51 of the tubular portion 42 and the opening liquid passage 61 of the drain portion 44 communicate with each other, and the tubular portion 42 and the drain portion 44 are tubular. It is also a part that changes from the part 42 to the drain part 44. The transition portion 43 is mostly a cross-sectional shape shown in FIG. 4C, and is a portion formed when the medical drain tube 41 is formed by extrusion molding.

  The transition part 43 usually has a congruent cross-sectional shape in the majority of the transition part 43. This cross-sectional shape is a shape in which the tubular portion 42 and the drain portion 44 are combined. Specifically, as shown in FIG. 4C, the circular-shaped tubular wall 53 and one end thereof are substantially perpendicular to each other. It has four partition walls (also referred to as support portions or support walls) that are connected to each other and connected to the inner peripheral surface of the tubular wall 53 at the other end. Then, four lumens (also referred to as closed liquid passages) 55 extending in the axial direction and closed in a non-communication state by two partition walls 54 and the tubular wall 53 adjacent in the circumferential direction are formed in the tubular wall 53. Yes. The partition wall 54 is connected to the end portion of the support portion 63 and extends integrally in the axial direction. Accordingly, each of the lumens 55 has one end communicating with the shaft hole 51 and the other end communicating with one open liquid passage 61. Here, as described above, each of the lumens 55 is not in communication with the other lumens 55 by the partition walls 54. The partition wall 54 is also called a support wall because it extends in the axial direction.

  In the medical drain tube 41 having such a configuration, the body fluid or the like entering from the opening 62 of the drain part 44 is circulated independently in each of the four open liquid passages 61 and the inner lumen 55, and the shaft hole 51. Mix with and drain out of the body.

  The preferred medical drain tube 41 has been described above, but the medical drain tube manufactured by the method for producing a medical drain tube of the present invention is not limited to the preferred medical drain tube 41. For example, various medical drain tubes having different cross-sectional shapes can be manufactured by appropriately changing the crosshead die of the present invention described later.

Moreover, the drain part and transition part of a medical drain tube should just be formed with at least two support parts or a partition, and it is preferable that it is formed with 3-5 support parts or a partition, and four support parts. Or it is more preferable to form with the partition.
Further, the drain part and the transition part are formed by connecting a support part or a partition wall to each other at one end thereof, but a desired cross-sectional shape, for example, a circular shaft body and a radial shape from the outer peripheral surface of the shaft body at equal intervals. It may be formed to have a support portion or a partition wall protruding.

  As long as the crosshead type extruder of the present invention includes the crosshead die of the present invention, other structures and the like are not particularly limited, and known structures and the like can be appropriately employed.

  A crosshead type extruder 1 as an example of a crosshead type extruder of the present invention includes, for example, a cylinder (also referred to as a barrel) 2 in which a screw (not shown) is housed, and a screw as shown in FIG. And a crosshead die 5 connected to the extruder. The extruder has a drive mechanism (not shown), a supply port (not shown) for charging a molding material into the cylinder 2, and the like. This cross head die 5 is a preferred example of the cross head die of the present invention.

As described above, the cylinder 2 and the like in this crosshead extruder 1 can be used without any particular limitation, and thus illustration and description thereof are omitted.
For example, the crosshead type extruder may be a single screw extruder or a multi-screw extruder.

As shown in FIG. 1, the crosshead die 5 includes a crosshead die body 11 having a flow channel cavity 16 of a molding material, and an out die 12 having a discharge port 17 mounted on the downstream side of the flow channel cavity 16. The inner die 13 disposed in the discharge port 17 and the inner die 13 are embedded in the inner peripheral surface of the discharge port 17 or disposed on the discharge side surface 18 of the out die 12 so as to be movable back and forth in the radial direction of the discharge port 17. And the movable claw 14 capable of forming the opening 62.
As shown in FIGS. 1 and 2, the inner die 13 moves forward and backward with respect to the fixed inner die 21 capable of forming the support portion 63 of the drain portion 44 and the partition wall 54 of the transition portion 43 and the discharge port 17. The movable inner die 22 is supported so as to be capable of forming the shaft hole 51 together with the fixed inner die 21.

The crosshead die 5 will be described in detail with a focus on the inner die 13 and the movable claw 14.
FIG. 2A is a side view showing an example of a fixed inner die, and FIG. 2B is a front view showing an example of a fixed inner die. FIG. 2C is a side view showing an example of the movable inner die, and FIG. 2D is a front view showing an example of the movable inner die. FIG. 2E is a side view showing an example of the inner die, and FIG. 2F is a front view showing an example of the inner die.
Since the configuration other than the inner die 13 and the movable claw 14 is basically the same as that of a known crosshead die, description thereof is omitted.

As shown in FIGS. 1 and 3, the out die 12 has a substantially disk shape and has a discharge port 17 penetrating in the thickness direction at the center thereof. The inner diameter of the discharge port 17 is adjusted to be equal to the outer diameter of the medical drain tube 41 to be manufactured. The thickness of the out die 12 is not particularly limited, but it is preferable to ensure a sufficient thickness when the operating claw 14 is embedded.
FIG. 3 shows an excerpt of the vicinity of the discharge port 17 of the out die 12.

  The inner die 13 has a fixed inner die 21 that is supported in a stationary state and a movable inner die 22 that is supported so as to be able to move forward and backward in the axial direction of the crosshead die 5. The inner die 13 can be disposed at the front end portion in the discharge port 17, and the front end surface can be disposed substantially flush with the discharge-side surface 18 (see FIG. 1) of the out die 12. Specifically, the distal end portion 23 b of the fixed inner die 21 is disposed in the discharge port 17 so as to be flush with the discharge-side surface 18, and the distal end portion 27 of the movable inner die 22 can be disposed inside and outside the discharge port 17. It has become.

As shown in FIGS. 2A and 2B, the fixed inner die 21 has a large-diameter portion 23a and a tip portion 23b connected to one end of the large-diameter portion 23a via a tapered portion 23c. doing. The large-diameter portion 23a only needs to be able to interpolate the movable inner die 22, and in this example, is formed in a substantially cylindrical tubular body. The large-diameter portion 23a may be formed with four gaps extending in the axial direction like the tip portion 23b.
The tapered portion 23c only needs to be able to connect the large diameter portion 23a and the distal end portion 23b, and does not have to have four gaps.

  The tip portion 23 b has a shape capable of forming the support portion 63 of the drain portion 44 and the partition wall 54 of the transition portion 43. Specifically, the tip portion 23b is circularly arranged in four rows so that the cross-sectional fan-shaped column bodies 24 face each other with the gap 25 in the circumferential direction and the outer circumferential surface 26 faces the outside. Is formed. In this way, the rod-shaped body, which is a solid cylindrical body, is formed by cutting out four gaps 25 (also referred to as grooves) in the radial direction from the center. That is, the cross-sectional shape of the tip portion 23 b is a circle having a cross-shaped gap 25. The number of column bodies 24 is set to an appropriate number according to the number of support portions 63 and partition walls 54.

  As shown in FIGS. 2C and 2D, the movable inner die 22 is a rod-shaped body having a circular cross section having a tip portion 27 corresponding to the gap 25 of the fixed inner die 21. That is, the distal end portion 27 is formed by four wall bodies extending radially and in the axial direction, and a cross-sectional shape perpendicular to the axial direction is a cross shape. And this front-end | tip part 27 is fitted by the front-end | tip part 23b (gap 25) of the fixed inner die | dye 21, and forms the cylindrical body which can shape | mold the shaft hole 51 in cooperation with the front-end | tip part 23b. 2 (e), 2 (f), and 3, the movable inner die 22 is supported so as to move forward and backward with respect to the discharge port 17 in the fixed inner die 21, particularly in the distal end portion 23b. Has been. Note that the shape of the distal end portion 27 of the movable inner die 22 is appropriately set according to the shape of the gap 25 so as to correspond to the gap 25 provided at the distal end portion 27 of the fixed inner die 21.

As shown in FIGS. 1 and 3, four movable claws 14 are disposed on the discharge side surface 18 of the out die 12 at equal intervals along the circumferential direction of the discharge port 17. The distal end portion 28 of the movable claw 14 has a shape (planar shape) in the thickness direction capable of forming the opening 62 of the drain portion 44. Specifically, the movable claw 14 is a flat plate with a pentagonal plan shape having a rectangular base portion 28a having a constant width and a triangular tip 28b. The distal end portion 28 of the movable claw 14 is formed by the distal end 28b and a part of the rectangular base portion 28a. Preferably, the opening 62 is formed by the rectangular base portion 28a. The movable claw 14 preferably has a thickness of 3 to 8 mm because the opening 62 can be formed as desired. The number of movable claws 14 is appropriately set so as to match the number of openings 62.
In the present invention, the movable claw 14 need not have a pentagonal plan shape, and various shapes can be adopted. For example, it may be a rectangular planar shape consisting only of the rectangular base portion 28a.

  The movable claw 14 is mounted on the discharge-side surface 18 so as to be movable in the radial direction of the discharge port 17 with a screw (not shown).

  The movable claw 14 is disposed on the discharge-side surface 18, but is embedded in the out die 12 so as to protrude from the inner peripheral surface of the discharge port 17 and to retreat until it is flush with the inner peripheral surface. Also good.

  The medical drain tube manufacturing method of the present invention is a manufacturing method of manufacturing the above medical drain tube using the crosshead type extruder of the present invention, depending on the tubular part, the transition part and the drain part. In this method, each of the inner die and the movable claw is moved forward and backward to perform extrusion molding.

At this time, in consideration of the cross-sectional shape of the medical drain tube and the shape of the tip of the inner die and the movable claw, the shape formed by the inner peripheral surface of the outlet of the out die 12 and the tip of the inner die and the movable claw The inner die and the movable claw are moved forward and backward independently so as to correspond to the cross-sectional shapes of the extruding portion of the medical drain tube, that is, the tubular portion, the transition portion, and the drain portion.
In this way, the tip of the inner die is disposed in or retracted from the outlet of the out die 12, and the tip of the movable claw is disposed inward of the outlet or retracted outward, so that The cross-sectional shape can be adjusted.
Therefore, in the method for producing a medical drain tube of the present invention, the medical drain tube can be produced in the order of the tubular portion, the transition portion and the drain portion by the method of moving the inner die and the movable claw forward and backward. The drain part, the transition part, and the tubular part can also be manufactured in this order.

  The inner die and the movable claw may be moved back and forth manually or may be moved back and forth by various actuators.

  Below, the manufacturing method of the medical drain tube of this invention is demonstrated concretely.

A preferred method for producing a medical drain tube of the present invention (referred to as a preferred first production method of the present invention) in which the medical drain tube 41 is produced in the order of the tubular part 42, the transition part 43 and the drain part 44 is preferably a cloth. A head type extruder 1 is used.
This crosshead type extruder 1 is as described above, and the distal end portion 23b of the fixed inner die 21 is disposed inside the discharge port 17 so that the end surface thereof is flush with the discharge side surface 18 of the out die 12. It is fixed to the state.

  A preferred first manufacturing method of the present invention includes a step of forming the tubular portion 42 by disposing the movable inner die 22 in the discharge port 17 and retracting the movable claw 14 radially outward of the discharge port 17. Preferably, the step of forming the transition portion 43 by retracting the inner die 22 from the discharge port 17 and the step of forming the drain portion 44 by advancing the movable claw 14 inward of the discharge port 17 in the radial direction are preferably performed. Do it continuously.

  In the present invention, “continuously performed” means that no other molding step is performed between the above-described molding steps, that is, the continuity of the molding step. It doesn't mean that. Therefore, in the method for producing a medical drain tube of the present invention, the above-described molding step may be performed at intervals in time, that is, with a stop or a pause, within a range that does not affect the molding quality or the like. it can.

  In the preferred first manufacturing method of the present invention, first, the movable inner die 22 is advanced until the distal end surface of the distal end portion 27 of the movable inner die 22 is flush with the discharge-side surface 18 of the out die 12 to move the distal end portion 27. Arranged in the outlet 17. Then, as shown in FIG. 3A, the inner die 13 forms a solid rod-shaped body with a circular cross section together with the distal end portion 23 b of the fixed inner die 21 arranged in advance in the discharge port 17. Further, the movable claw 14 is retracted outward in the radial direction until at least the distal end portion 28 is located outside the outer edge of the discharge port 17. If it does so, the extrusion part 31 of the molding material formed with the out die | dye 12 and the inner die | dye 13 will become cyclic | annular, as FIG. 3 (a) shows. When the inner die 13 and the movable claw 14 are arranged in this way and the molding material is extruded, the tubular portion 42 having an annular cross section is molded. Note that the molding material thus extruded is preferably taken up by a take-up machine by allowing air to flow into the inner hole corresponding to the shaft hole 51 of the tubular portion 42.

  In the preferred first manufacturing method of the present invention, the transition portion 43 is subsequently formed. In order to form the transition portion 43, the movable inner die 22 is retracted from the discharge port 17 in the inner die 13 and the movable claw 14 that are disposed when the tubular portion 42 is formed.

  That is, the movable inner die 22 is retracted in the axial direction, and the tip portion 27 is retracted and retracted from the discharge port 17. Then, as shown in FIG. 3B, only the fixed inner die 21 is disposed in the discharge port 17 of the inner die 13. The movable claw 14 remains retracted. When the movable inner die 13 is moved backward without moving the movable claw 14 in this way, the extruded portion 31 of the molding material formed by the out die 12 and the inner die 13 has the shape shown in FIG. . When the molding material is extruded in such an arrangement, the transition portion 43 having the tubular wall 53 and the partition wall 54 is molded.

  When the movable inner die 22 is retracted, the flow channel volume of the flow channel cavity 16 of the molding material slightly varies by the amount of the movable inner die 22. Along with this variation, the extrusion speed of the molding material when molding the tubular portion 42 and the extrusion speed of the molding material when molding the transition portion 43 slightly vary. Therefore, the extruded molding material has a slightly smaller outer diameter than before the movable inner die 22 is retracted. However, as will be described later, in the vulcanization process, the molding material extruded as the tubular portion 42 is easily heat-shrinked in the radial direction, and the outer diameter difference when extruded is offset. Therefore, the outer diameter difference between the tubular portion 42 and the transition portion 43 is reduced by passing through the vulcanization step without specially adjusting the extrusion amount and take-up speed of the molding material.

  In the preferred first manufacturing method of the present invention, the drain portion 44 is subsequently formed. In order to form the drain part 44, the movable claw 14 is advanced in the radial direction to the inside of the discharge port 17.

  That is, with the movable inner die 22 retracted, the movable claw 14 disposed outside the discharge port 17 is radially extended to the inside of the discharge port 17, preferably the tip 28b of the movable claw 14 is fixed to the fixed inner die. The tip part 28 is moved inward of the discharge port 17 until it reaches the inside of the discharge port 17. As described above, when the movable claw 14 is advanced without moving the movable inner die 13 forward, the inner die 13 has the fixed inner die 21 and the movable claw 14 within the discharge port 17 as shown in FIG. The cross-sectional shape is formed by the fixed inner die 21 and the movable claw 14. When the molding material is extruded in such an arrangement, the drain part 44 having the support part 63 and the protruding part 64 is molded.

  Even if the movable claw 14 is advanced, the flow volume of the flow channel cavity 16 of the molding material does not change. Therefore, the extrusion speed of the molding material when molding the transition portion 43 and the extrusion speed of the molding material when molding the drain portion 44 become constant, and the amount of extrusion of the molding material, the take-up speed, etc. need not be adjusted specially. In addition, the transition part 43 and the drain part 44 having no difference in outer diameter can be formed.

In the preferred first production method of the present invention, when thermosetting silicone rubber is used as the molding material, the molding material is vulcanized simultaneously with or after the extrusion molding.
The vulcanization of the molding material may be performed under the condition that the molding material is vulcanized and cured by a heating means such as a heating furnace, and is appropriately set according to the molding material to be used.

  In the preferred first production method of the present invention, the tubular portion 42, the transition portion 43, and the drain portion 44 can be extruded in this order to produce a medical drain tube. As described above, in the manufactured medical drain tube, at least the transition part 43 and the drain part 44 have a uniform outer diameter. Therefore, according to the preferred first manufacturing method of the present invention, the medical drain tube 41 having at least the transition part 43 and the drain part 44 having a uniform outer diameter can be molded with good molding workability.

  A preferable method for producing a medical drain tube of the present invention (referred to as a preferred second production method of the present invention) in which the medical drain tube 41 is produced in the order of the drain part 44, the transition part 43 and the tubular part 42 is the molding order. Except for the difference, this is basically the same as the preferred first production method of the present invention.

  In the preferred second manufacturing method of the present invention, the movable inner die 22 is moved backward from the discharge port 17 and the movable claw 14 is advanced in the radial direction to the inside of the discharge port 17, preferably using the crosshead type extruder 1. Forming the drain portion 44, retreating the movable claw 14 in the radial direction to the outside of the discharge port 17, forming the transition portion 43, and advancing the movable inner die 22 into the discharge port 17. The step of forming the tubular portion 42 is preferably performed continuously.

  In the preferred second manufacturing method of the present invention, first, the movable inner die 22 is retracted in the axial direction, and the tip 27 is retracted and retracted from the discharge port 17. Further, the movable claw 14 arranged outside the discharge port 17 is moved forward in the radial direction to the inside of the discharge port 17, preferably until the tip 28 b reaches the inside of the fixed inner die 21. The portion 28 is disposed inside the discharge port 17. Then, in the inner die 13, as shown in FIG. 3C, the fixed inner die 21 and the movable claw 14 are arranged in the discharge port 17. When the molding material is extruded in such an arrangement, the drain portion 44 is molded.

  In the preferred second manufacturing method of the present invention, the transition portion 43 is subsequently formed. In order to form the transition portion 43, the movable claw 14 disposed when the drain portion 44 is formed is retracted from the discharge port 17. That is, the movable claw 14 is retracted outward in the radial direction until at least the distal end portion 28 is located outside the outer edge of the discharge port 17. Note that the movable inner die 22 remains retracted. Then, as shown in FIG. 3B, the inner die 13 has only the fixed inner die 21 disposed in the discharge port 17, and the pushing portion 31 has the shape shown in FIG. 3B. When the molding material is extruded in such an arrangement, the transition portion 43 is molded.

  In the preferred second manufacturing method of the present invention, the tubular portion 42 is subsequently formed. In order to form the tubular portion 42, the movable inner die 22 is placed in the discharge port 17 until the end surface of the distal end portion 27 of the movable inner die 22 disposed when forming the transition portion 43 is flush with the discharge-side surface 18. Move forward. That is, the movable inner die 22 is advanced to place the tip 27 in the discharge port 17. As a result, the inner die 13 has a solid circular shape as shown in FIG. The movable claw 14 remains retracted. Thereby, the extrusion part 31 becomes cyclic | annular as FIG. 3 (a) shows. When the molding material is extruded in such an arrangement, the tubular portion 42 is molded.

  In the preferred second production method of the present invention, the drain part 44, the transition part 43, and the tubular part 42 can be extruded in this order to produce a medical drain tube. And like the suitable 2nd manufacturing method of this invention, as for the medical drain tube manufactured, at least the transfer part 43 and the drain part 44 have a uniform outer diameter. Therefore, according to the preferred second manufacturing method of the present invention, the medical drain tube 41 having at least the transition part 43 and the drain part 44 having a uniform outer diameter can be molded with good molding workability.

The molding material used in the method for producing a medical drain tube of the present invention is not particularly limited, but is preferably a silicone rubber composition in terms of biocompatibility, mechanical properties, and the like.
In the present invention, a thermosetting silicone rubber composition can also be used. If the thermosetting silicone rubber composition is changed to a different cross-sectional shape during molding because it takes time to vulcanize or it is not vulcanized until it enters the vulcanization furnace, It is known that the diameter is likely to change. However, as described above, the method for producing a medical drain tube of the present invention can reduce the change in the volume of the flow path cavity during extrusion to prevent the change in the outer diameter, and uses the thermosetting silicone rubber composition. You can also.

The thermosetting silicone rubber composition is not particularly limited as long as it is cured by heat, and a known one can be appropriately used.
For example, average composition formula: RnSiO _{(4-n) / 2} (R may be the same or different, substituted or unsubstituted monovalent hydrocarbon group, preferably 1 to 12 carbon atoms, more preferably carbon. It is a monovalent hydrocarbon group having 1 to 8 atoms, and n is a positive number of 1.95 to 2.05.) A thermosetting silicone rubber composition containing an organopolysiloxane represented by the formula:
Further, it contains an organopolysiloxane containing at least two alkenyl groups bonded to silicon atoms in one molecule, and an organohydrogenpolysiloxane containing at least two hydrogen atoms bonded to silicon atoms in one molecule. A thermosetting silicone rubber composition is also mentioned.

Example 1
Using the following thermosetting silicone rubber composition and the extruder 1 shown in FIG. 1 equipped with the inner die 21 shown in FIG. 2, the medical drain tube 41 shown in FIG. Setting).
<Thermosetting silicone rubber composition>
100 parts by weight of silicone raw rubber (trade name “KE-78VBS”, manufactured by Shin-Etsu Chemical Co., Ltd.) and 43 parts by weight of hydrophobic fumed silica (trade name “Aerosil R974”, manufactured by Nippon Aerosil Co., Ltd.) The mixture was uniformly mixed using a mixer and heat treated at 150 ° C. for 2 hours to prepare a silicone rubber compound. Next, 100 parts by mass of this silicone rubber compound, 2.0 parts by mass of organohydrogenpolysiloxane (trade name “C-25B”, manufactured by Shin-Etsu Chemical Co., Ltd.), platinum-based catalyst (trade name “C-25A”, Shin-Etsu Chemical) (Made by Kogyo Co., Ltd.) 0.5 parts by mass was blended and kneaded with a mixing roll to obtain an addition reaction type silicone rubber composition.
In the extruder 1, the outer diameter of the extrusion part 31 that forms the outer shape of the product was set to 5.2 mm, and the inner diameter of the extrusion part 31 that formed the inner diameter was set to 3.2 mm.

The thermosetting silicone rubber composition was sequentially and continuously extruded so as to become a tubular portion 42, a transition portion 43, and a drain portion 44 by the preferred first manufacturing method of the present invention. Specifically, the movable inner die 22 was disposed in the discharge port 17 and the movable claw 14 was retracted in the radial direction to the outside of the discharge port 17 to form the tubular portion 42. Next, the movable inner die 22 was retracted from the discharge port 17 to form the transition portion 43. Finally, the movable claw 14 was advanced in the radial direction to the inside of the discharge port 17 to form the drain portion 44, thereby obtaining an extruded product. The extruded extruded body was heated at 400 ° C. and vulcanized to produce a medical drain tube 41.
In the medical drain tube 41, when the outer diameters of the transition portion 43 and the drain portion 44 were measured, the ratio of the outer diameter of the tubular portion 42 to the outer diameter (5.077 mm) of the transition portion 43 was 101.4%. The ratio of the outer diameter of the drain part 44 to the outer diameter of the transition part 43 was 97.5%.

(Comparative Example 1)
A medical drain tube was manufactured by the manufacturing method described in Patent Document 2 using the thermosetting silicone rubber composition.
Annular shafts 41 and 61 and a shaft 81 shown in Patent Document 2, particularly shown in FIG. 4, were prepared, and these were combined to constitute the die 11 shown in FIG.
The outer diameter of the extrusion part 31 forming the outer shape of the product was set to 5.2 mm, and the inner diameter of the extrusion part 31 forming the inner diameter was set to 3.2 mm.

This die 11 is operated based on “operation of die” (column 9 to column 11 of Patent Document 2), and the thermosetting silicone rubber composition is continuously extruded at 400 ° C. Heated and vulcanized. In this way, a medical drain tube was manufactured.
In the medical drain tube manufactured based on the die and method described in Patent Document 2, the outer diameters of the transition part and the drain part were measured, and the outer diameter of the tubular part 42 with respect to the outer diameter (5.124 mm) of the transition part 43 was measured. The ratio of the diameter was 98.4%, and the ratio of the outer diameter of the drain part 44 to the outer diameter of the transition part 43 was 91.7%.

1 Crosshead Extruder 2 Cylinder 5 Crosshead Die 11 Crosshead Die Body 12 Out Die (Outer Die)
13 Inner die (Indie)
14 movable claw 16 channel cavity 17 discharge port 18 discharge side surface 21 fixed inner die 22 movable inner die 23a large diameter portion 23b tip portion 23c tapered portion 24 column body 25 gap 26 outer peripheral surface 27 tip portion 28 tip portion 28a rectangular base portion 28b Tip 31 Extrusion part 41 Medical drain tube 42 Tubular part 43 Transition part 44 Drain part 51 Shaft hole 52 Tubular wall 53 Tubular wall 54 Partition wall (supporting part)
55 Lumen (closed fluid path)
61 Opening fluid path 62 Opening (groove)
63 Supporting part (supporting wall)
64 Projection

Claims (10)

A tubular portion having an axial hole, a drain portion having a plurality of open liquid passages having openings extending in the axial direction in a non-communication state by a support portion, and an inner end communicating with the shaft hole and the open liquid passage A crosshead die of a crosshead type extruder for extruding a medical drain tube having a cavity in a tubular wall in a state of non-communication with a partition wall and comprising a transition portion connecting the tubular portion and the drain portion There,
An out die having a discharge port, an inner die disposed in the discharge port, embedded in an inner peripheral surface of the discharge port, or disposed on the discharge side surface of the out die so as to be movable forward and backward in the radial direction of the discharge port, A movable claw capable of forming the opening of the drain part,
The inner die is supported so as to be able to move forward and backward with respect to the discharge port, and the shaft hole together with the fixed inner die. A crosshead die having a movable inner die that can be formed.   The crosshead die according to claim 1, wherein the movable inner die is supported so as to move forward and backward in the fixed inner die.   The crosshead die according to claim 1 or 2, wherein the movable claw is attached to the discharge side surface by screwing. The fixed inner die has a tip portion in which a plurality of circular pillars having a fan-shaped cross section are arranged in a ring with a gap in the circumferential direction,
The crosshead die according to claim 1, wherein the movable inner die has a tip portion corresponding to the gap of the fixed inner die.   The crosshead die according to claim 4, wherein the tip end portion of the fixed inner die is formed by cutting a groove in a radial direction from the center of a solid cylindrical body.   A crosshead type extruder comprising the crosshead die according to any one of claims 1 to 5. A tubular portion having an axial hole, a drain portion having a plurality of open liquid passages having openings extending in the axial direction in a non-communication state by a support portion, and an inner end communicating with the shaft hole and the open liquid passage The crosshead type extruder according to claim 6, wherein the medical drain tube is provided with a transition part connecting the tubular part and the drain part, the cavity part having a cavity in the tubular wall in a non-communication state by a partition wall. A manufacturing method for manufacturing using:
A method for manufacturing a medical drain tube, wherein the movable inner die and the movable claw are respectively moved forward and backward in accordance with the tubular portion, the transition portion, and the drain portion. Arranging the movable inner die in the discharge port, retreating the movable claw radially outward to the outside of the discharge port, and forming the tubular portion;
Retreating the movable inner die from the discharge port, and forming the transition portion;
The method for manufacturing a medical drain tube according to claim 7, wherein the movable claw is advanced inward in the radial direction to the inside of the discharge port, and the drain portion is formed. Retreating at least the movable inner die from the inside of the discharge port and advancing the movable claw radially inward to the inside of the discharge port, and forming the drain portion;
Retreating the movable claw radially to the outside of the discharge port, and forming the transition portion;
The method for manufacturing a medical drain tube according to claim 7, wherein the movable inner die is advanced into the discharge port to form the tubular portion. The method for producing a medical drain tube according to any one of claims 7 to 9, wherein the thermosetting silicone rubber composition is extruded.

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