Medical cap and production method for same

Abstract

Provided are: a medical cap in which there is no liquid leakage upon puncture with a needle, which has excellent holding force against needle dislodgement, and in which an elastic plug body is prevented from falling out from an outer frame body; and a production method for the same. A medical cap 1 according to the present invention comprises an elastic plug body 20 and an outer frame body 10 which has an annular body section 11 and a support section 12. The annular body section 11 has an inner wall 11b that surrounds and closely contacts a lateral circumferential section 23 of the elastic plug body 20, an outer wall 11a that surrounds the inner wall 11b, and a slit 11d that runs vertically through the inner wall 11b. The inner wall 11b is downward and separate from the outer wall 11a. The support section 12 has an upper support section 12a that supports the lateral circumferential section 23 of the elastic plug body 20 from an upper surface side, a lower support section 12b that provides support from the lower surface side, and a connecting section 12d that connects the upper support section 12a and the lower support section 12b. The connecting section 12d is embedded in the slit 11d. The lower support section 12b is embedded between the inner wall 11b and the outer wall 11a. The support section 12 is welded to the elastic plug body 20 and the annular body section 11.

Description

Medical cap and method for manufacturing the same

[0001] The present invention relates to a medical cap for use with infusion containers, blood collection tubes, vials, and other drug containers, and a method for manufacturing the same. In particular, the present invention relates to a medical cap for medical use that prevents leakage when a needle is stuck and has excellent retention against needle slippage, and a method for manufacturing the same.

[0002] Drug containers used in the medical field, such as drug solution bottles and intravenous fluid bottles, utilize medical caps that allow the drug solution to be dispensed with a needle. These caps include rubber stoppers or caps with an elastic stopper (e.g., rubber or elastomer resin) housed inside an outer frame. In the latter type of medical cap, the outer frame is attached to the mouth of the drug container by welding or other means. When in use, a needle equipped with a dispensing tube is inserted into the elastic stopper, and the drug container is positioned upwards with the medical cap downwards, allowing the infusion fluid inside the container to be dispensed via the dispensing tube. Furthermore, such medical caps require airtightness to prevent leakage of the drug solution or infusion fluid and to prevent deterioration due to exposure to air.

[0003] As mentioned above, a medical cap comprising, for example, a substantially cylindrical stopper and an outer frame that houses the stopper inside has been disclosed (Patent Document 1). In this medical cap, the lower bottom of the stopper and the upper part of the bottom holding portion of the outer frame are welded to each other, and the side portion of the stopper and the inner wall of the side circumference of the outer frame are in contact in a non-welded state. According to Patent Document 1, this prevents the needle of a puncture needle inserted into the stopper from coming out, and ensures resealability and airtightness.

[0004] Furthermore, Patent Document 2 discloses a medical cap comprising a stopper and an outer frame that houses the stopper, wherein the outer frame has at least an upper side circumferential portion and a lower leg portion that has a welded portion with the side circumferential portion. In addition, in this medical cap, the side circumferential portion of the stopper holds the stopper by contacting the side portion of the stopper from the side direction in a non-welded state at its inner wall, and the leg portion has a structure in which at least a part of its upper portion is welded to the peripheral edge of the liquid-contacting surface of the stopper. According to Patent Document 2, this makes it possible to improve resealability and prevent needle detachment.

[0005] However, in the medical caps described in these patent documents, the side portion of the stopper body is in contact with the inner wall of the outer frame body in a non-welded state. Therefore, when using a large-diameter needle, such as a spiked needle used to transfer drugs like anticancer agents from one container to another, there is a problem that the peripheral edge of the needle-piercing surface of the stopper body will detach from the outer frame body.

[0006] Japanese Patent Publication No. 2001-130614, Japanese Patent Publication No. 2001-212204, Japanese Patent Publication No. 2001-212845

[0007] The present invention has been made in view of the above-mentioned problems, and its purpose is to provide a medical cap and a method for manufacturing the same that prevents liquid leakage when a needle is stuck, has excellent retention force against needle dislodgement, and prevents the elastic stopper from falling off the outer frame.

[0008] The medical cap according to the present invention, in order to solve the above problems, is a medical cap comprising an elastic plug body and an outer frame body that holds the elastic plug body inside, wherein the outer frame body has an annular portion and a support portion, the annular portion has an inner wall that surrounds the side circumference of the elastic plug body in a tightly fitted state, an outer wall that surrounds the inner wall, and at least one slit portion that longitudinally intersects the inner wall, and the support portion has an upper support portion that supports the side circumference of the elastic plug body from the upper side, and a lower support portion that supports the side circumference of the elastic plug body from the lower side, and The device has an upper support portion and at least one connecting portion that connects the lower support portion, the inner wall is a downward-hanging wall that is connected to the inner surface of the outer wall at its upper end and whose wall surface is spaced apart from the outer wall, the lower support portion is embedded between the inner wall and the outer wall and presses the side circumference of the elastic plug body through the inner wall, the connecting portion embeds the slit portion, the elastic plug body is in close contact with the contact surface of the annular portion, and the support portion is welded to the contact surface of the elastic plug body and the annular portion.

[0009] In the above configuration, it is preferable that a notch is provided at the lower end of the inner wall.

[0010] Furthermore, in the above configuration, it is preferable that the lower surface side of the circumferential portion of the elastic plug body is provided with a male tapered portion that gradually decreases in diameter towards the lower surface of the elastic plug body.

[0011] Furthermore, in the above configuration, when the lower support portion is not embedded between the inner wall and the outer wall, it is preferable that the inner wall protrudes downward from the lower end surface of the outer wall.

[0012] Furthermore, in the above configuration, it is preferable that the inner wall surface is provided with a locking portion for locking the side circumference of the elastic plug body housed inside the inner wall.

[0013] The present invention provides a method for manufacturing a medical cap in order to solve the above problems, and is characterized by including: an annular body molding step of molding the annular body using a common mold and a first mold; a placement step of placing the elastic plug inside the annular body with its upper surface facing downward; and a support part molding step of molding the support part using the common mold and a second mold having a ring-shaped projection having a diameter smaller than the lower surface of the elastic plug, while pressing the peripheral edge of the lower surface of the elastic plug placed inside the annular body with the ring-shaped projection.

[0014] In the above configuration, it is preferable that the support molding step involves injecting molten resin for molding the support between the inner wall and the outer wall of the annular body to form the support.

[0015] Furthermore, in the above configuration, it is preferable that the support part molding process involves injecting the molten resin between the inner wall and the outer wall of the annular part at the central position of the inner wall to form the support part.

[0016] Furthermore, in a configuration in which a notch is provided at the lower end of the inner wall, it is preferable that the support molding process involves injecting molten resin for molding the support between the inner wall and the outer wall of the annular body at the location where the notch is provided to mold the support.

[0017] The medical cap of the present invention comprises an elastic plug body and an outer frame body that holds the elastic plug body inside, the outer frame body having an annular portion and a support portion. Furthermore, the annular portion comprises an inner wall that surrounds the side circumference of the elastic plug body in close contact, an outer wall that surrounds it at a distance from the inner wall, and at least one slit portion that crosses the inner wall longitudinally. The support portion has a structure comprising an upper support portion that supports the side circumference of the elastic plug body from the top side, a lower support portion that supports the side circumference from the bottom side, and at least one connecting portion that connects the upper support portion and the lower support portion and embeds the slit portion. The lower support portion is also embedded between the inner wall and the outer wall, so that the lower support portion presses against the side circumference of the elastic plug body via the inner wall. The support portion is welded to the elastic plug body and the annular portion at the contact surface. Therefore, according to the present invention, even when a large-diameter puncture needle, such as a spiked needle, is inserted into the elastic stopper, it is possible to prevent the elastic stopper from falling off the outer frame. Furthermore, leakage of liquid during needle insertion can be effectively prevented. Moreover, since the elastic stopper is only in close contact with the annular portion at the inner wall, it is held inside the outer frame without being constrained by the annular portion, compared to the support portion which is welded at the contact surface. Therefore, it prevents the needle from coming out when a puncture needle is inserted into the elastic stopper, and the resealing properties of the elastic stopper can be effectively maintained even after repeated needle insertion and removal. In other words, according to the present invention, it is possible to provide a medical cap and a method for manufacturing the same that prevents liquid leakage during needle insertion, has excellent holding power against needle removal, and prevents the elastic stopper from falling off the outer frame.

[0018] Figure 1(a) is a perspective view of a medical cap according to one embodiment of the present invention, viewed from the needle-piercing side, and Figure 1(b) is a perspective view of the medical cap viewed from the liquid-contacting side. Figure 2(a) is a plan view of a medical cap according to one embodiment of the present invention, viewed from the needle-piercing side, and Figure 2(b) is a plan view of a medical cap viewed from the liquid-contacting side, and Figure 2(c) is a cross-sectional view of the medical cap shown in Figure 2(a) along the line A-A'. Figure 3(a) is a perspective view of the annular body portion before it is incorporated into the medical cap according to one embodiment of the present invention, viewed from below, Figure 3(b) is a plan view of the annular body portion viewed from below, and Figure 3(c) is a plan view of a medical cap viewed from above. Figure 4(a) is a cross-sectional view of the annular body portion shown in Figure 3(c) along the line B-B', Figure 4(b) is a side view of the annular body portion, and Figure 4(c) is an enlarged cross-sectional view of the main part of the annular body portion. Figure 5(a) is a schematic perspective view of an elastic stopper according to one embodiment of the present invention, Figure 5(b) is a plan view of the elastic stopper viewed from the needle-piercing surface side, Figure 5(c) is a plan view of the elastic stopper viewed from the liquid-contacting surface side, and Figure 5(d) is a side view of the elastic stopper. This is a cross-sectional view for explaining a method for manufacturing a medical cap according to one embodiment of the present invention, where Figure 5(a) shows the process of forming an annular body using a first upper mold and a common lower mold, Figure 5(b) shows the elastic stopper placed on the annular body, and Figure 5(c) shows a second upper mold and a common lower mold to which the annular body on which the elastic stopper is placed is fixed. This is an enlarged cross-sectional view showing the main part of the common lower mold. Figure 8(a) shows the second upper mold and the common lower mold closed together; Figure 8(b) shows the process of forming the support part using the second upper mold and the common lower mold; and Figure 8(c) shows the medical cap being manufactured and the second upper mold and the common lower mold opened. Figure 9(a) is a perspective view from below of the other annular body part before it is incorporated into the medical cap according to one embodiment of the present invention; Figure 9(b) is a plan view of the other annular body part viewed from below; Figure 9(c) is a cross-sectional view taken along the line C-C' in the other annular body part shown in Figure 9(b); and Figure 9(b) is a side view of the annular body part.Figure 10(a) is a perspective view from below of the other annular body portion before it is incorporated into a medical cap according to one embodiment of the present invention, and Figure 10(b) is a perspective view from above of the other annular body portion. Figure 11(a) is a perspective view from below of the other annular body portion before it is incorporated into a medical cap according to one embodiment of the present invention, and Figure 11(b) is a perspective view from above of the other annular body portion. Figure 12(a) is an enlarged cross-sectional view of the main part of the annular body portion having an engaging portion consisting of an annular groove on the inner circumferential surface of the outer wall, Figure 12(b) is an enlarged cross-sectional view of the main part of the annular body portion having an engaging portion consisting of an annular protrusion on the outer circumferential surface of the outer wall, and Figure 12(c) is an enlarged cross-sectional view of the main part of the annular body portion having an engaging portion consisting of an annular groove on the outer circumferential surface of the outer wall. Figure 13(a) is a perspective view of another elastic stopper according to one embodiment of the present invention, viewed from the needle-piercing surface side; Figure 13(b) is a perspective view of the other elastic stopper viewed from the fluid-contacting surface side; and Figure 13(c) is a side view of the other elastic stopper. Figure 14(a) is a schematic perspective view of a port member equipped with a medical cap according to another embodiment of the present invention; and Figure 14(b) is a cross-sectional view of a boat member. This is a schematic cross-sectional view of a medical cap according to another embodiment of the present invention. Figure 16(a) is a schematic cross-sectional view of a medical cap according to another embodiment of the present invention; and Figure 16(b) is a schematic cross-sectional view of another second upper mold that enables the molding of a lower support portion equipped with an engaging portion. This is a schematic cross-sectional view of a medical cap according to Comparative Example 1.

[0019] (Medical Cap) The medical cap according to this embodiment will be described below based on the drawings. Note that in each figure, parts that are not necessary for the explanation have been omitted, and parts have been enlarged or reduced to facilitate the explanation.

[0020] As shown in Figures 1 and 2, the medical cap 1 according to this embodiment comprises at least an outer frame 10 and an elastic stopper 20 held inside the outer frame 10. Figure 1(a) is a perspective view of the medical cap 1 according to one embodiment of the present invention as seen from the needle-piercing surface 21 side, and Figure 1(b) shows the medical cap 1 as seen from the liquid-contacting surface 22 side. Figure 2(a) is a plan view of the medical cap 1 as seen from the needle-piercing surface 21 side, Figure 2(b) is a plan view as seen from the liquid-contacting surface 22 side, and Figure 2(c) is a cross-sectional view of the medical cap 1 shown in Figure 2(a) along the line A-A'. In this specification, "needle-piercing surface" means the surface on which the medical cap 1 according to this embodiment is attached to a drug container and is pierced by a puncture needle when dispensing a drug solution, etc. Also, in this specification, "liquid-contacting surface" means the surface on which the drug solution, etc. stored in the drug container comes into contact.

[0021] The outer frame 10 comprises an annular body portion 11 with an overall cylindrical shape and a support portion 12 that supports the side circumference 23 of the elastic plug 20 from the needle-piercing surface 21 side and the liquid-contacting surface 22 side. The annular body portion 11 and the support portion 12 are welded to each other at their contact surfaces, thereby forming an integrated structure that constitutes the outer frame 10. The annular body portion 11 is in close contact with the contact surface of the elastic plug 20 without welding. The support portion 12 is welded to the contact surface of the elastic plug 20. In this specification, "welding" means, as described later, that when the support portion 12 is molded by injection molding or the like, the heat of the molten resin injected melts the surfaces of the annular body portion 11 and the elastic plug 20 that are in contact with it, resulting in a state where the support portion 12 is joined to the annular body portion 11 and the elastic plug 20 at their contact surfaces after molding.

[0022] As shown in Figures 2(a), 2(c), 3(a) to 3(c), and 4(a) to 4(c), the annular body portion 11 comprises an outer wall 11a and an inner wall 11b. Figure 3(a) is a perspective view of the annular body portion 11 from below before it is incorporated as a component material of the medical cap 1, Figure 3(b) is a plan view of the annular body portion 11 from below, and Figure 3(c) is a plan view of the annular body portion 11 from above. Furthermore, Figure 4(a) is a cross-sectional view of the annular body portion 11 taken along the line B-B' shown in Figure 3(c), Figure 4(b) is a side view of the annular body portion 11, and Figure 4(c) is an enlarged cross-sectional view of the main part of the annular body portion 11.

[0023] The outer wall 11a is provided so as to surround the inner wall 11b. The inner wall 11b is connected to the inner surface of the outer wall 11a at its upper end via an inner wall connecting portion 11e. As shown in Figures 4(a) and 4(c), the connection position by the inner wall connecting portion 11e is at a position a distance below the upper end surface of the outer wall 11a. Furthermore, the inner wall 11b hangs down with its wall surface separated from the outer wall 11a, forming a downward-sloping wall. The annular body portion 11 houses the elastic plug 20 such that the inner wall 11b surrounds it. The inner surface of the inner wall 11b is in close contact with the side circumference 23 of the elastic plug 20 without welding, thereby holding the elastic plug 20 inside the outer frame 10 without being constrained by the annular body portion 11. Therefore, it prevents the needle from coming out when the puncture needle is inserted into the elastic plug 20, and also ensures good resealability after the puncture needle is inserted and removed again.

[0024] Furthermore, the outer wall 11a and the inner wall 11b are spaced apart, except for the connecting portion (i.e., the inner wall connecting portion 11e). The spacing between the outer wall 11a and the inner wall 11b may be narrower towards the bottom of the outer wall 11a and the inner wall 11b, or they may be equidistant, before the annular body portion 11 is incorporated as a component of the medical cap 1. In the former case, it facilitates the flow of molten resin for forming the support portion 12 between the outer wall 11a and the inner wall 11b.

[0025] An engaging portion 11f is provided on the inner circumferential surface of the outer wall 11a, above the inner wall connecting portion 11e (i.e., in the direction opposite to the direction in which the inner wall 11b hangs down) (Figures 4(a) and 4(c)). The engaging portion 11f consists of a protruding portion that is provided in an annular shape in the circumferential direction of the annular body portion 11. The engaging portion 11f also has the function of engaging the molded annular body portion 11 with the mold and temporarily fixing it in place when the mold is opened after the annular body portion 11 has been molded. The vertical cross-sectional shape of the engaging portion 11f is not particularly limited as long as it is able to engage with the mold and does not result in excessive mold release failure when the annular body portion 11 is released from the mold. Specifically, the vertical cross-sectional shape of the engaging portion 11f may be, for example, a triangular shape as shown in Figure 4(c), or a semicircular shape, etc. Furthermore, it is preferable that the vertical cross-sectional shape of the engaging portion 11f is substantially uniform over the entire circumference of the inner circumferential surface of the outer wall 11a. Furthermore, the "vertical cross-sectional shape" of the engaging portion 11f refers to the cross-sectional shape obtained by cutting with a plane that passes through the center point of the annular body portion 11 and includes the vertical direction of the outer wall 11a.

[0026] As shown in Figure 2(b), the lower support portion 12b of the support portion 12 is embedded between the outer wall 11a and the inner wall 11b (details of the support portion 12 will be described later). When the lower support portion 12b is embedded, the inner wall 11b is deformed in a direction that reduces its diameter. As a result, the lower support portion 12b can press against the side circumference 23 of the elastic plug body 20 housed inside the inner wall 11b via the inner wall 11b, and as a result the elastic plug body 20 is held inside the outer frame 10 in a state in which the liquid contact surface 22 side is deformed into a concave shape. By holding the elastic plug body 20 in a deformed state, it is possible to improve the holding force against needle removal, the restoring force, and the resealability after needle removal.

[0027] Before the annular portion 11 is incorporated as a component of the medical cap 1, the inner wall 11b protrudes downward from the lower end surface of the outer wall 11a, as shown in Figure 4(b). By adopting this configuration, the inner wall 11b can be pressed so as to sufficiently cover the side circumference 23 of the elastic plug 20. However, the present invention is not limited to this embodiment. For example, the lower end surface of the inner wall 11b may be at the same height as the lower end surface of the outer wall 11a, or the lower end surface of the outer wall 11a may be lower than the lower end surface of the inner wall 11b.

[0028] The inner wall 11b is provided with four slit portions 11d. The slit portions 11d are longitudinally sectional in the vertical direction between the needle-piercing surface 21 and the liquid-contacting surface 22 of the elastic stopper body 20, and as a result the inner wall 11b is the first inner wall 11b １ ~4th inner wall 11b ４ It is composed of four inner walls. The four slit portions 11d are arranged to be equally spaced from one another. Furthermore, in a plan view, each slit portion 11d virtually forms the same arc shape with respect to the center point O of the annular body portion 11 (see Figure 3(c)). The slit portions 11d with this configuration function as flow channels for the molten resin that is the constituent material of the support portion 12 when the support portion 12 is molded (details will be described later). In addition, the slit portions 11d allow for the embedding of the connecting portion 12d that connects the upper support portion 12a and the lower support portion 12b of the support portion 12, which will be described later.

[0029] The width of the slit portion 11d (or the length of the virtual arc in plan view) can be appropriately set according to the number of slit portions 11d and the width (or length) of the connecting portion 12d in plan view. Furthermore, as described above, since each slit portion 11d virtually forms an arc shape in plan view, the central angle θ at the center point O of the annular body portion 11 １ The number of slits 11d and the width of the connecting portion 12d can also be set according to the number of slits 11d and the width of the connecting portion 12d. The central angle θ １ The central angle θ is usually 45° or less, preferably in the range of 5° to 45°, and more preferably in the range of 10° to 40°. １By setting it to 45° or less, it is possible to prevent the width of the inner wall 11b (or the arc length in a plan view) from becoming excessively narrow. As a result, it is possible to prevent the area of the contact surface between the inner wall 11b and the side peripheral portion 23 of the elastic plug body 20 from becoming too small and the pressing force of the inner wall 11b against the elastic plug body 20 from decreasing. Consequently, it becomes possible to hold the elastic plug body 20 in a sufficiently deformed state and maintain good holding force, restoring force against needle removal, and resealing performance after needle removal. Incidentally, the central angle θ １ When it is 5° or more, it is possible to ensure a good flow path for the molten resin which is the constituent material of the support portion 12. As a result, it becomes possible to fill a sufficient amount of molten resin to form the upper support portion 12a, and the upper support portion 12a can be formed well. Furthermore, it is possible to prevent the connecting portion 12d connecting the upper support portion 12a and the lower support portion 12b from becoming excessively small and maintain good connection between the upper support portion 12a and the lower support portion 12b. Also, the central angle θ １ is 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 35, 40, 45°, and may also be within the range between any two of the numerical values exemplified here.

[0030] Also, the number of slit portions 11d in the present invention is not particularly limited, and for example, it may be 1, 2, 3, 4, 6, or 8. When a plurality of slit portions 11d are provided, it is preferable that each slit portion 11d is provided at equal intervals from each other.

[0031] Also, at the center of the lower end portions of the first inner wall 11b １ to the fourth inner wall 11b ４ , notch portions 11c are provided respectively as shown in FIGS. 3(a) and 4(a). The notch portion 11c is rectangular, and when forming the support portion 12, the molten resin injection gate is the first inner wall 11b １ to the fourth inner wall 11b ４Contact with the support portion can be avoided. The notch 11c can also function as a flow path for the molten resin, which is a component of the support portion 12 (details will be described later). The size of the notch 11c can be appropriately set according to the position and size of the molten resin injection gate, the flow rate of the molten resin, etc. Furthermore, the shape of the notch 11c is not limited to a rectangular shape. For example, it may be trapezoidal, triangular, or the like.

[0032] Also, the first inner wall 11b １ ~4th inner wall 11b ４ Each of these is formed in an arc shape with respect to the center point O of the annular body portion 11. First inner wall 11b １ ~4th inner wall 11b ４ The central angle θ ２ This refers to the number of slit portions 11d and the central angle θ of the slit portions 11d. １ The value can be set appropriately depending on the central angle θ. ２ The central angle θ is usually 115° or less, preferably in the range of 18° or more and 115° or less, more preferably in the range of 45° or more and 115° or less, and even more preferably in the range of 50° or more and 110° or less. ２ By setting the central angle to 115° or less, the width of the slit portion 11d (or the length of the virtual arc in a plan view) is prevented from becoming excessively narrow. This ensures a good flow path for the molten resin, which is the constituent material of the support portion 12. As a result, a sufficient amount of molten resin can be filled to form the upper support portion 12a, and the upper support portion 12a can be molded well. Furthermore, the connecting portion 12d that connects the upper support portion 12a and the lower support portion 12b is prevented from becoming excessively small, and the connection between the upper support portion 12a and the lower support portion 12b can be maintained well. Note that the central angle θ ２When it is 20° or more, it is possible to suppress the width of the inner wall 11b (or the length of the arc in plan view) from becoming excessively narrow. As a result, it is possible to prevent the area of the contact surface between the inner wall 11b and the side peripheral portion 23 of the elastic plug 20 from becoming too small and the pressing force of the inner wall 11b against the elastic plug 20 from decreasing. As a result, it is possible to hold the elastic plug 20 in a sufficiently deformed state, and it is possible to maintain good holding force, restoring force against needle removal, and re-sealing property after needle removal. Also, the central angle θ ２ is 18, 20, 23, 30, 34, 38, 40, 45, 49, 50, 55, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 75, 79, 80, 85, 90, 95, 98, 100, 105, 109, 110, 115°, and it may also be within the range between any two of the numerical values exemplified here.

[0033] The thickness of the outer wall 11a is not particularly limited as long as the mechanical strength as the outer frame 10 can be maintained. Also, the thickness of the outer wall 11a is preferably uniform. The thickness of the inner wall 11b is not particularly limited as long as the pressing force of the lower support portion 12b against the elastic plug 20 can be transmitted. Also, the thickness of the inner wall 11b may be uniform, or may be configured to become thinner toward the lower end surface.

[0034] Here, the thickness w1 of the outer wall 11a shown in FIG. 4(c) is preferably equal to or greater than the thickness t of the inner wall connecting portion 11e that connects the inner wall 11b to the outer wall 11a. Thereby, in the outer wall 11a, in the region of portions A to C surrounded by the broken line shown in FIG. 4(c), it is possible to prevent or suppress the occurrence of sink marks. Also, the thickness w2 of the inner wall 11b is preferably substantially the same as or smaller than the thickness t of the inner wall connecting portion 11e. Thereby, when forming the annular body portion 11, it is possible to prevent or suppress the inner wall 11b from falling down.

[0035] As shown in FIGS. 1 and 2, the support portion 12 has an upper support portion 12a, a lower support portion 12b, and four connecting portions 12d.

[0036] As shown in Figures 2(a) and 2(c), the upper support portion 12a supports the side circumference 23 of the elastic plug body 20 from the needle puncture surface 21 side. Specifically, the upper support portion 12a is annular and supports the elastic plug body 20 by welding it to a stepped portion (details will be described later) provided on the needle puncture surface 21 side of the side circumference 23 of the elastic plug body 20. By welding the upper support portion 12a to the stepped portion of the elastic plug body 20, it is possible to prevent the elastic plug body 20 from detaching from the outer frame body 10 even when a large-diameter puncture needle, such as a spiked needle, is inserted into the needle puncture surface 21.

[0037] As shown in Figures 2(a) and 2(c), the lower support portion 12b supports the side circumference 23 of the elastic plug body 20 from the wetted surface 22 side. Specifically, the lower support portion 12b is annular and supports the elastic plug body 20 by welding it to a male tapered portion (details will be described later) provided on the wetted surface 22 side of the side circumference 23 of the elastic plug body 20. By welding the lower support portion 12b to the male tapered portion of the elastic plug body 20, it is possible to prevent the elastic plug body 20 from falling off the outer frame body 10, similar to the case of the upper support portion 12a. In addition, the lower support portion 12b is also embedded between the outer wall 11a and the inner wall 11b (hereinafter, the part of the lower support portion 12b that is embedded between the outer wall 11a and the inner wall 11b will be called the embedded portion 12c). The embedded portion 12c is pressed against the side circumference 23 of the elastic plug body 20 via the inner wall 11b of the annular portion 11. As a result, the elastic plug body 20 is held inside the outer frame 10 in a deformed state in which the needle-piercing surface 21 is convex and the liquid-contacting surface 22 is concave. The shape of the embedded portion 12c is not particularly limited and is determined as appropriate by the shape of the space between the outer wall 11a and the inner wall 11b, the amount of molten resin flowing into the space during the molding of the support portion 12, and the injection pressure.

[0038] Furthermore, in the lower support portion 12b, an annular wall 12f is provided around the periphery of the opening where the liquid-contacting surface 22 of the elastic stopper 20 is exposed (see Figures 1(b) and 2(c)). The annular wall 12f hangs down in the direction opposite to the needle-piercing surface 21. This annular wall 12f has the function of fitting and connecting with the mouth of the drug container when the medical cap 1 is attached to the drug container.

[0039] As shown in Figures 1(b) and 2(b), four gate marks 12e are provided on the peripheral edge of the outer surface of the lower support portion 12b at equal intervals from one another. Here, "gate marks" refer to the traces of the gate, which is the injection port for molten resin into the cavity of the mold, and have an uneven shape formed on the molded body (in this embodiment, the lower support portion 12b). When molding the support portion 12, the molten resin injection gate is located on the first inner wall 11b １ ~4th inner wall 11b ４ It is positioned to correspond to the formation position of the notch 11c provided therein. Therefore, the gate mark 12e is located on the first inner wall 11b １ ~4th inner wall 11b ４ The gate mark 12e is formed in accordance with the position of the notch 11c provided therein. The gate mark 12e is substantially circular in shape when viewed from above. The shape and size of the gate mark 12e in a plan view are determined according to the opening shape and area of ​​the molten resin injection gate, the type of runner, etc., and are not particularly limited.

[0040] As shown in Figure 2(a), the connecting portion 12d connects the upper support portion 12a and the lower support portion 12b. The connecting portion 12d is columnar and is provided to fill the four slit portions 11d provided in the inner wall 11b. Since the connecting portion 12d is welded to the contact surface with the side circumference 23 of the elastic plug body 20, it serves to prevent the elastic plug body 20 from falling off the outer frame body 10, similar to the case of the upper support portion 12a and the lower support portion 12b.

[0041] As the material constituting the outer frame 10 (annular body portion 11 and support portion 12), synthetic resins whose safety for medical use has been established can be suitably used. Among these, thermoplastic resins are generally used. Specifically, resins conventionally used for medical applications such as high-density polyethylene, low-density polyethylene, linear low-density polyethylene, polypropylene, and PET (polyethylene terephthalate) resin are preferred, but the present invention is not limited to these. Furthermore, since the annular body portion 11 and the support portion 12 are welded together to constitute the outer frame 10, it is preferable that the constituent materials used for each are the same material or compatible materials. In addition, any component such as a colorant may be added to either the annular body portion 11 or the support portion 12, or both.

[0042] As shown in Figures 1(a) and 1(b), the elastic stopper body 20 is housed inside the outer frame body 10 with the needle-piercing surface 21 facing upwards and the liquid-contacting surface 22 facing downwards. The needle-piercing surface 21 is provided with a recess 21a that serves as a position indicator when piercing with a puncture needle. The recess 21a is circular in plan view, but the present invention is not limited to this embodiment. Furthermore, the number and size of the recesses 21a (or its diameter if the recess 21a is circular in plan view) are not particularly limited, and it is sufficient to provide at least one recess 21a.

[0043] Furthermore, as shown in Figure 2(c), the elastic stopper 20 is held inside the outer frame 10 with the needle-piercing surface 21 deformed into a convex shape and the liquid-contacting surface 22 deformed into a concave shape. The degree to which the needle-piercing surface 21 and the liquid-contacting surface 22 are deformed is not particularly limited. For example, the entire structure may be deformed into a convex or concave shape, or the central part may be deformed into a convex or concave shape. Alternatively, the elastic stopper 20 may be held in the outer frame 10 with the needle-piercing surface 21 deformed into a concave shape and the liquid-contacting surface 22 deformed into a convex shape. Or, both the needle-piercing surface 21 and the liquid-contacting surface 22 may be deformed into a convex shape.

[0044] The overall shape of the elastic plug 20 is not particularly limited, but in this embodiment, as shown in Figures 5(a) to 5(d), it is substantially cylindrical. A stepped portion 23b is provided on the needle-piercing surface 21 side of the circumferential portion 23. Since the stepped portion 23b engages with the upper support portion 12a of the support portion 12, it is possible to further prevent the elastic plug 20 from detaching from the outer frame 10 when, for example, removing a puncture needle that has been pierced into the elastic plug 20. Preferably, the entire surface of the stepped portion 23b is welded to the upper support portion 12a. If the needle-piercing surface 21 is at a higher position than the upper support portion 12a, and a part of the stepped portion 23b is exposed without being welded to the upper support portion 12a, when a puncture needle is pierced into the needle-piercing surface 21 of the elastic plug 20, the deformation of the elastic plug 20 at the needle-piercing position becomes larger, and the contact area between the puncture needle and the elastic plug 20 increases. As a result, the penetration resistance of the puncture needle increases, which is undesirable.

[0045] Furthermore, a male tapered portion 23a is provided on the side of the circumferential portion 23 that is in contact with the liquid surface 22, and the diameter gradually decreases as it approaches the liquid surface 22 of the elastic stopper 20. By providing the male tapered portion 23a, compared to the case where it is not provided, it is possible to prevent the circumferential portion 23 on the liquid surface 22 side of the elastic stopper 20 from being excessively heated and melted by the molten resin during the molding of the support portion 12 (details of the molding method of the support portion 12 will be described later). The inclination angle α of the tapered surface of the male tapered portion 23a with respect to the horizontal plane (see Figure 5(d)) should be set to an extent that prevents excessive heating and melting by the molten resin, depending on the molding conditions of the support portion 12. Figure 5(a) is a schematic perspective view of the elastic stopper 20, Figure 5(b) is a plan view of the elastic stopper 20 viewed from the needle-piercing surface 21 side, Figure 5(c) is a plan view of the elastic stopper 20 viewed from the liquid-contacting surface 22 side, and Figure 5(d) is a side view of the elastic stopper 20.

[0046] In the medical cap 1 according to this embodiment, the elastic plug 20 is housed inside the outer frame 10, pressed from the male tapered portion 23a side by the embedded portion 12c via the inner wall 11b. As a result, compressive stress (crimping force) acts on the elastic plug 20 toward its center, causing the needle-piercing surface 21 to deform into a convex shape and the liquid-contacting surface 22 to deform into a concave shape. The elastic plug 20 is not welded to the annular portion 11 that constitutes the outer frame 10. Here, the annular portion 11 is welded to the support portion 12 at the contact surface, so even when a large-diameter puncture needle, such as a spiked needle, is inserted into the elastic plug 20, it is possible to prevent the elastic plug 20 from detaching from the support portion 12. As a result, leakage of liquid during needle-piercing can be effectively prevented. Furthermore, the elastic plug 20 is in close contact with the annular portion 11 without being welded to it at the contact surface. Therefore, it prevents the needle from coming out when the puncture needle is inserted into the elastic plug 20, and also allows the elastic plug 20 to exhibit good resealing properties even after the puncture needle has been inserted and removed again.

[0047] (Method for Manufacturing Medical Caps) Next, the method for manufacturing the medical cap 1 according to this embodiment will be explained based on Figures 6 to 8. Figure 6 is a cross-sectional view for explaining the method for manufacturing the medical cap 1, where Figure (a) shows the process of forming the annular body portion 11 using a first upper mold (first mold) 31 and a common lower mold (common mold) 32, Figure (b) shows the elastic plug 20 placed on the annular body portion 11, and Figure (c) shows a second upper mold (second mold) 33 and a common lower mold 32 to which the annular body portion 11 with the elastic plug 20 placed on it is fixed. Figure 7 is an enlarged cross-sectional view showing the main part of the common lower mold 32. Figure 8 is a cross-sectional view illustrating the manufacturing method of the medical cap 1. Figure (a) shows the second upper mold 33 and the common lower mold 32 in a closed state, Figure (b) shows the process of forming the support part 12 using the second upper mold 33 and the common lower mold 32, and Figure (c) shows the medical cap 1 after it has been manufactured and the second upper mold 33 and the common lower mold 32 have been opened. Note that in each figure, parts that are not necessary for the explanation have been omitted, and parts have been enlarged or reduced to facilitate explanation.

[0048] The manufacturing method for the medical cap 1 includes an annular body molding step of forming an annular body portion 11, a placement step of placing an elastic plug 20 on the molded annular body portion 11, and a support portion molding step of forming a support portion 12.

[0049] The annular body molding process is carried out by injection molding the annular body 11 using a first upper mold 31 and a common lower mold 32, as shown in Figure 6(a). The first upper mold 31 is a core (convex mold), and the common lower mold 32 is a cavity (concave mold). The first upper mold 31 and the common lower mold 32 are structured so that when both are closed, a cavity is formed in which the annular body 11 can be molded. The first upper mold 31 is also provided with a spool (not shown) through which molten resin injected from an injection molding machine flows, a runner 31a as a passage for guiding the molten resin from the spool into the cavity, and a molten resin injection gate 31b for injecting molten resin into the cavity. The molten resin injection gate 31b is positioned so that its position is at the lower end surface of the outer wall 11a of the annular body 11 to be molded. As shown in Figures 6(a) and 7, the common lower mold 32 is provided with an annular groove 32a on the inner circumferential surface of the outer wall 11a of the annular body portion 11 for forming the aforementioned engaging portion 11f. The groove 32a is provided in an annular shape on the inner wall surface of the common lower mold 32, corresponding to the position where the engaging portion 11f is formed above the inner wall connecting portion 11e on the inner circumferential surface of the outer wall 11a of the annular body portion 11. This makes it possible to form the engaging portion 11f, which consists of an annular projection, on the inner circumferential surface of the outer wall 11a.

[0050] In molding the annular body portion 11, the molten resin, which is the constituent material of the annular body portion 11, passes through a spool (not shown) and runner 31a in the first upper mold 31 and is injected into the cavity through the molten resin injection gate 31b. The injection pressure is not particularly limited and can be set as appropriate. The injected molten resin is cooled in the cavity for a predetermined time. This forms the annular body portion 11. The cooling time is not particularly limited and can be set as appropriate. There may be multiple molten resin injection gates 31b. In this case, it is preferable that each molten resin injection gate 31b is provided at equal intervals from one another.

[0051] As shown in Figure 6(b), the placement process involves opening the first upper mold 31 and the common lower mold 32, and then placing the elastic plug 20 inside the annular body portion 11. Here, the engaging portion 11f provided on the inner circumferential surface of the outer wall 11a of the annular body portion 11 and the groove portion 32a provided on the inner surface of the common lower mold 32 are engaged. Therefore, when opening the first upper mold 31 and the common lower mold 32, the annular body portion 11 adheres tightly to the first upper mold 31, preventing mold release defects. As a result, a decrease in manufacturing efficiency can be prevented. Furthermore, the elastic plug 20 is placed so that the needle-piercing surface (upper surface) 21 faces downward. The manufacturing method of the elastic plug 20 is not particularly limited; for example, it can be manufactured by compression molding or injection molding, which involves crushing a thermoplastic elastomer.

[0052] The support part molding process is performed by injection molding the support part 12 using a second upper mold 33 and a common lower mold 32, as shown in Figure 6(c). The second upper mold 33 is a core (convex mold). The second upper mold 33 and the common lower mold 32 are structured such that when both are closed, a cavity is formed into which the support part 12 can be molded. The second upper mold 33 is also provided with a spool (not shown) through which molten resin injected from an injection molding machine flows, a runner 33a as a passage for guiding the molten resin from the spool into the cavity, and four molten resin injection gates 33b for injecting molten resin into the cavity. The four molten resin injection gates 33b are at equal intervals from each other, and each is located on the first inner wall 11b of the annular body part 11. １ ~4th inner wall 11b ４ The second upper mold 33 is positioned to correspond to the formation position of the notch 11c provided therein. Furthermore, as shown in Figure 6(c), the second upper mold 33 is provided with a ring-shaped projection 33c for pressing against the peripheral edge of the liquid-contacting surface 22 of the elastic stopper 20. The ring-shaped projection 33c also has the function of preventing molten resin from flowing between the liquid-contacting surface 22 of the elastic stopper 20 and the inside of the ring-shaped projection 33c by bringing the ring-shaped projection 33c into contact with the peripheral edge of the liquid-contacting surface 22.

[0053] The outer diameter r of the ring-shaped projection 33c is set appropriately according to the shape and size of the support portion 12 to be molded, but it is preferable that it be smaller than the diameter of the wetted surface 22 of the elastic stopper 20. However, if the outer diameter r is too small, the lower support portion 12b of the support portion 12 will be molded to be larger than necessary, resulting in a smaller area through which the puncture needle can penetrate, which may reduce the convenience of needle insertion.

[0054] Furthermore, the height h of the ring-shaped projection 33c is not particularly limited and is set appropriately according to the size of the elastic plug 20 and the shape of the support part 12 to be molded. Usually, it is preferably in the range of 0.3 mm to 8 mm, and more preferably in the range of 0.8 mm to 6 mm. By setting the height h to 8 mm or less, it is possible to prevent difficulty in closing the mold between the second upper mold 33 and the common lower mold 32. On the other hand, by setting the height h to 0.3 mm or more, it is possible to prevent insufficient pressing on the elastic plug 20, which would prevent the generation of compressive stress toward the center of the elastic plug 20.

[0055] As shown in Figure 8(a), when the second upper mold 33 and the common lower mold 32 are closed, the ring-shaped projection 33c contacts and deforms the peripheral edge of the liquid-contacting surface 22 of the elastic stopper body 20. As a result, the liquid-contacting surface 22 side becomes convex. In addition, by contacting the ring-shaped projection 33c with the peripheral edge of the liquid-contacting surface 22 of the elastic stopper body 20, it prevents molten resin from flowing into the gap between the liquid-contacting surface 22 of the elastic stopper body 20 and the second upper mold 33.

[0056] Next, as shown in Figure 8(b), molten resin, which is the constituent material of the support part 12, is injected into the cavity formed by closing the mold. The molten resin passes through the spool and runner 33a in the second upper mold 33 and is injected into the cavity from the molten resin injection gate 33b. Here, the molten resin injected into the cavity first flows between the outer wall 11a and the inner wall 11b of the annular body part 11, and then, after being guided by the inner wall 11b, it heads towards the slit portions 11d provided on both sides of the inner wall 11b. The molten resin that reaches the slit portions 11d then flows further toward the male tapered portion 23a of the elastic plug 20. In addition, a portion of the molten resin injected between the outer wall 11a and the inner wall 11b also flows toward the male tapered portion 23a of the elastic plug 20 from the notch portion 11c provided in the inner wall 11b. This enables the molding of the lower support portion 12b, which is welded to the male tapered portion 23a of the elastic plug body 20. Furthermore, since a space is formed between the slit portion 11d and the side circumference 23 of the elastic plug body 20 that is not in close contact with the inner wall 11b, some of the molten resin that reaches the slit portion 11d flows through this space as a flow path to the needle-piercing surface 21 side of the elastic plug body 20. This enables the molding of the upper support portion 12a, which is welded to the stepped portion 23b of the elastic plug body 20. In addition, the molten resin that fills this space forms a connecting portion 12d that connects the upper support portion 12a and the lower support portion 12b. The injected molten resin is cooled in the cavity for a predetermined time. The injection pressure is not particularly limited and can be set as appropriate. Similarly, the cooling time is not particularly limited and can be set as appropriate. After the mold is opened, the support portion 12 is formed as shown in Figure 8(c). Here, after the mold is opened, the liquid-contacting surface 22 of the elastic stopper body 20 becomes concave as a result of the release of pressure from the ring-shaped projection 33c.

[0057] As a result, an outer frame 10 is formed in which the annular body portion 11 and the support portion 12 are integrated, and a medical cap 1 according to this embodiment is obtained.

[0058] (Other Matters) In the embodiments described above, the medical cap of the present invention was described using as an example an annular body of the outer frame in which a notch is provided in the inner wall. However, the present invention is not limited to this embodiment. For example, as shown in Figures 9(a) to 9(c), the annular body 41 may have an inner wall 42 composed of a first inner wall 42a to a fourth inner wall 42d that does not have a notch. Figure 9(a) is a perspective view from below of another annular body before it is incorporated into a medical cap according to another embodiment of the present invention, Figure 9(b) is a plan view of the other annular body when viewed from below, Figure 9(c) is a cross-sectional view taken along the line C-C' in the other annular body shown in Figure 9(b), and Figure 9(b) is a side view of the annular body. In this case, the four molten resin injection gates for injecting molten resin into the cavity in order to injection mold the support portion 12 are arranged so that the molten resin can be injected between each of the first inner wall 42a to the fourth inner wall 42d and the outer wall 11a, in the central part of each of the first inner wall 42a to the fourth inner wall 42d.

[0059] Furthermore, the annular portion of the outer frame may be one in which a locking portion is provided on the inner surface of the inner wall for locking the side circumference of the elastic plug. Examples of the locking portion include the protruding portion 45 shown in Figures 10(a) and 10(b). Figure 10(a) is a perspective view from below of another annular portion before it is incorporated into a medical cap according to another embodiment of the present invention, and Figure 10(b) is a perspective view from above of the other annular portion. The protruding portions 45 shown in these figures each extend vertically through the central part of each wall surface from the first inner wall 44a to the fourth inner wall 44d and protrude from the wall surface. As a result, the annular portion 43 shown in Figures 10(a) and 10(b) can properly support the elastic plug 20 when it is placed inside the inner wall 44. Furthermore, the locking portion may be a projection 48 as shown in Figures 11(a) and 11(b). The projections 48 shown in these figures extend horizontally across the central portion of each wall surface from the first inner wall 47a to the fourth inner wall 47d, and protrude from the wall surface. As a result, even in the annular body portion 46 shown in Figures 11(a) and 11(b), the elastic plug 20 can be well supported when the elastic plug 20 is placed inside the inner wall 47.

[0060] Furthermore, in the above-described embodiment, the medical cap of the present invention was described using as an example an embodiment in which the rod-shaped portion is provided with an engaging portion consisting of a protruding portion of an annular part on the inner circumferential surface of the outer wall and above the inner wall connecting portion. However, the present invention is not limited to this embodiment. For example, the engaging portions 11g to 11i shown in Figures 12(a) to 12(c), respectively, may also be used. Figure 12(a) is an enlarged cross-sectional view of the main part of an annular body portion 11 having an engaging portion 11g consisting of an annular groove on the inner circumferential surface of the outer wall 11a, Figure 12(b) is an enlarged cross-sectional view of the main part of an annular body portion 11 having an engaging portion 11h consisting of an annular protruding portion on the outer circumferential surface of the outer wall 11a, and Figure 12(c) is an enlarged cross-sectional view of the main part of an annular body portion 11 having an engaging portion 11i consisting of an annular groove on the outer circumferential surface of the outer wall 11a.

[0061] The engaging portion 11g shown in Figure 12(a) is located on the inner circumferential surface of the outer wall 11a and is provided above the inner wall connecting portion 11e. The engaging portion 11g consists of an annular groove in the circumferential direction of the annular body portion 11. In this case, the common lower mold is provided with an annular projection on the inner circumferential surface of the outer wall 11a of the annular body portion 11 for forming the engaging portion 11g. The projection is provided in an annular shape on the inner wall surface of the common lower mold, corresponding to the position where the engaging portion 11g is formed on the inner circumferential surface of the outer wall 11a of the annular body portion 11 and above the inner wall connecting portion 11e. This makes it possible to form the engaging portion 11g, which consists of an annular groove, on the inner circumferential surface of the outer wall 11a.

[0062] The engaging portion 11h shown in Figure 12(b) is located on the outer circumferential surface of the outer wall 11a and is provided above the inner wall connecting portion 11e. The engaging portion 11h consists of an annular projection in the circumferential direction of the annular body portion 11. In this case, the common lower mold is provided with an annular groove for forming the engaging portion 11h on the outer circumferential surface of the outer wall 11a of the annular body portion 11. The groove is provided in an annular shape on the inner wall surface of the common lower mold, corresponding to the position where the engaging portion 11h is formed on the outer circumferential surface of the outer wall 11a of the annular body portion 11 and above the inner wall connecting portion 11e. This makes it possible to form the engaging portion 11h, consisting of an annular projection, on the outer circumferential surface of the outer wall 11a.

[0063] The engaging portion 11i shown in Figure 12(c) is located on the outer circumferential surface of the outer wall 11a and is provided above the inner wall connecting portion 11e. The engaging portion 11i consists of an annular groove in the circumferential direction of the annular body portion 11. In this case, the common lower mold is provided with an annular projection on the outer circumferential surface of the outer wall 11a of the annular body portion 11 for forming the engaging portion 11i. The projection is provided in an annular shape on the inner wall surface of the common lower mold, corresponding to the position where the engaging portion 11i is formed on the outer circumferential surface of the outer wall 11a of the annular body portion 11 and above the inner wall connecting portion 11e. This makes it possible to form an engaging portion 11i consisting of an annular groove on the outer circumferential surface of the outer wall 11a.

[0064] Furthermore, the vertical cross-sectional shape of the engaging portions 11g to 11i (the cross-sectional shape obtained by cutting with a plane that passes through the center point of the annular body portion 11 and includes the vertical direction of the outer wall 11a) is not particularly limited as long as it allows the lower support portion 12b to be temporarily fixed to the common lower mold and does not result in excessive mold release defects when releasing the medical cap 3 from the common lower mold. In addition, it is preferable that the vertical cross-sectional shape of the engaging portions 11g to 11i is substantially uniform over the entire circumference of the inner surface of the outer wall 11a.

[0065] Furthermore, in the above-described embodiment, the medical cap of the present invention was described using as an example an elastic stopper in which a male tapered portion is provided on the fluid-contacting surface side of the circumferential portion. However, the present invention is not limited to this embodiment. For example, as shown in Figures 13(a) to 13(c), a stepped portion 26 may be provided on the fluid-contacting surface 22 side of the circumferential portion 25. Figure 13(a) is a perspective view of the elastic stopper 24 as seen from the needle-insertion surface side, Figure 13(b) is a perspective view of the elastic stopper 24 as seen from the fluid-contacting surface side, and Figure 13(c) is a side view of the elastic stopper 24. By providing a stepped portion 26 on the fluid-contacting surface 22 side of the circumferential portion 25, it can be engaged with the lower support portion 12b of the support portion 12, thereby further preventing the elastic stopper 24 from detaching from the outer frame 10 when a puncture needle is inserted into the elastic stopper 24.

[0066] Furthermore, the medical cap of the present invention can also be applied to ports used in intravenous fluid bags and the like. An example of an intravenous fluid bag is one that comprises a rectangular bag body (not shown) capable of containing contents such as intravenous fluids, and a cylindrical port member that is inserted through and fixed to an opening provided in the center of one end of the bag body. For an intravenous fluid bag with such a configuration, the medical cap 2 of the present invention can be incorporated into its tip, as shown in Figures 14(a) and 14(b), for example, as shown in the port member 51. Figure 14(a) is a schematic perspective view of a port member 51 equipped with the medical cap 2, and Figure 14(b) is a cross-sectional view of the port member 51.

[0067] The medical cap 2 differs from the medical cap 1 according to the previously described embodiment in that its inner wall 11b' is a downward-sloping wall whose upper end is joined to the upper end surface of the outer wall 11a'. The port member 51 has a hollow cylindrical body 52 and a housing portion 53 provided at the tip of the cylindrical body 52 and housing the medical cap 2. The housing portion 53 is provided in an annular shape so as to protrude outward from the cylindrical body 52 and is formed coaxially with the cylindrical body 52. ​​In the medical cap 2 housed in the housing portion 53, only the needle-piercing surface 21 of the elastic plug 20 is exposed to the outside. The outer frame 10' is housed inside the housing portion 53 and is not visible from the outside. The outer frame 10' is welded to the contact surface of the housing portion 53.

[0068] Furthermore, the present invention can also adopt the embodiments of the medical cap 3 shown in Figure 15 and the medical cap 4 shown in Figure 16(a). Figures 15 and 16(a) are schematic cross-sectional views of medical caps according to other embodiments of the present invention. The medical cap 3 shown in Figure 15 differs from the medical cap 1 according to the above-described embodiment in that the lower support portion 12b has a flange portion 12g instead of an annular wall 12f. The flange portion 12g protrudes outward from the lower support portion 12b, enabling connection to the opening of a drug container or the like. This makes it possible to attach the medical cap 3 to the opening of a drug container or the like. In addition, an annular groove portion 12i is provided at an arbitrary position on the outer circumferential surface of the flange portion 12g, as shown in Figure 15. As a result, for example, by providing an annular projection on the second upper mold that allows for the formation of a groove 12i, the molded lower support portion 12b can be engaged with the second upper mold and temporarily fixed in place when the common lower mold and the second upper mold are opened after the lower support portion 12b has been molded. The vertical cross-sectional shape of the groove 12i (the cross-sectional shape obtained by cutting with a plane that passes through the center point of the support portion 12 and includes the vertical direction of the outer wall 11a) is not particularly limited as long as it allows the lower support portion 12b to be temporarily fixed to the second upper mold and does not result in excessive mold release defects when releasing the medical cap 3 from the second upper mold. Furthermore, it is preferable that the vertical cross-sectional shape of the groove 12i is substantially uniform around the entire circumference of the flange portion 12g.

[0069] The medical cap 4 shown in Figure 16(a) differs in that an engaging portion 12h is provided on the inner surface of the annular wall 12f of the lower support portion 12b. The engaging portion 12h consists of a protruding portion provided in an annular shape in the circumferential direction of the annular wall 12f. For a medical cap 4 having such a form, it is preferable to provide an annular groove on the outer surface of the cylindrical mouth portion of a drug container, etc., which is connected by inserting the mouth portion into the annular wall 12f, so that it can engage with the engaging portion 12h. This allows the medical cap 4 to be firmly connected to the mouth portion of the drug container, etc. The vertical cross-sectional shape of the engaging portion 12h (the cross-sectional shape cut by a plane that passes through the center point of the support portion 12 and includes the vertical direction of the annular wall 12f) is not particularly limited as long as it is capable of engaging with the mouth portion to the extent that the drug container, etc. does not detach. Furthermore, it is preferable that the vertical cross-sectional shape of the engaging portion 12h is substantially uniform over the entire circumference of the inner surface of the annular wall 12f.

[0070] The engaging portion 12h can be formed by using the second upper mold (second mold) 33' shown in Figure 16(b). Figure 16(b) is a schematic cross-sectional view of another second upper mold that enables the molding of the lower support portion 12b equipped with the engaging portion 12h. The second upper mold 33' shown in Figure 16(b) differs from the aforementioned second upper mold 33 in that it has an annular groove 33d on the outer circumferential surface of the ring-shaped projection 33c. In the molding of the lower support portion 12b, when the second upper mold 33 and the common lower mold 32 are opened, the engaging portion 12h and the groove 33d are engaged, so the medical cap 4 can adhere tightly to the common lower mold 32, preventing mold release defects. As a result, a decrease in manufacturing efficiency can be prevented.

[0071] Preferred embodiments of this invention will be described in detail below. However, unless otherwise specified, the materials and proportions described in the embodiments are not intended to limit the scope of this invention to those materials alone.

[0072] (Example 1) In this example, a medical cap 1 having the same structure as shown in Figures 1 and 2 was manufactured according to the method shown in Figures 6 and 7 described above. High-density polyethylene was used as the material for the annular body portion 11 and the support portion 12 that constitute the outer frame 10. Thermoplastic elastomer resin was used as the material for the elastic stopper 20. An injection molding machine (product name: DC100 / 200, manufactured by Nissei Plastic Industrial Co., Ltd.) was used as the molding machine. Ten samples of the medical cap 1 according to this example were produced. The central angle θ of the slit portion 11d １ The central angle of the arc (virtually formed in a plan view with respect to the center point O of the annular body portion 11) is 27°, and the central angle θ of the first inner wall 11b1 to the fourth inner wall 11b4 with respect to the center point O of the annular body portion 11 is set to 27°. ２ The angle was set to 63°.

[0073] The molding conditions for the annular body portion 11 are as follows: Injection molding temperature: 240°C Injection pressure: 4.0 MPa Injection time: 3.5 seconds First upper mold temperature: 20°C Common lower mold temperature: 25°C

[0074] The molding conditions for the support part 12 are as follows: Injection molding temperature: 240°C Injection pressure: 4.8 MPa Injection time: 4.0 seconds Second upper mold temperature: 20°C Common lower mold temperature: 25°C

[0075] (Comparative Example 1) In this comparative example, the medical cap 100 shown in Figure 17 was used. Figure 17 is a schematic cross-sectional view of the medical cap 100. The medical cap 100 shown in the figure comprises an elastic stopper 120 and an outer frame 110 that holds the elastic stopper 120 inside. An annular stepped portion 123b is provided on the needle-piercing surface 121 side of the side circumference 123 of the elastic stopper 120, and an annular stepped portion 123a is also provided on the liquid-contacting surface 122 side of the side circumference 123. The outer frame 110 comprises an annular portion 111 that supports the side circumference 123 of the elastic stopper 120 from the needle-piercing surface 121 side, and a support portion 112 that supports the side circumference 123 of the elastic stopper 120 from the liquid-contacting surface 122 side.

[0076] The annular portion 111 includes an inner wall 111b that surrounds the side circumference 123 of the elastic plug body 120 in a tightly fitted state, an outer wall 111a that surrounds the inner wall 111b, and an engaging portion 111c that engages with the stepped portion 123b of the elastic plug body 120. The inner wall 111b is connected to the inner surface of the outer wall 111a at its upper end and is a downward-hanging wall with its wall surface separated from the outer wall 111a. The inner wall 111b does not have notches or slits like the medical cap 1 of Embodiment 1.

[0077] The support portion 112 supports the side circumference 123 of the elastic plug body 120 from the liquid contact surface 122 side. Furthermore, by embedding the support portion 112 between the inner wall 111b and the outer wall 111a, it presses against the side circumference 123 of the elastic plug body 120 via the inner wall 111b. Note that the support portion 112 does not have a connecting portion for embedding the slit portion, as in the medical cap 1 of Embodiment 1.

[0078] The elastic plug 120 is in close contact with the annular body portion 111 at their contact surfaces. The support portion 112 is welded to the elastic plug 120 and the annular body portion 111 at their contact surfaces.

[0079] Furthermore, high-density polyethylene was used as the material for the annular portion 111 and the support portion 112 that constitute the outer frame 110. Thermoplastic elastomer resin was used as the material for the elastic stopper 120. The number of medical cap samples used in this comparative example was 10.

[0080] (Sterilization) Both the medical cap 1 of Example 1 and the medical cap 100 of Comparative Example 1 were sterilized in an autoclave at 105°C for 25 minutes.

[0081] (Leeping test of puncture needle) The medical cap 1 of Example 1 and the medical cap 100 of Comparative Example 1 (hereinafter sometimes referred to as "medical cap 1, etc.") were attached to a test pressure vessel after sterilization. The test pressure vessel used was one in which the opening with the medical cap 1, etc. attached could be fixed in either the up or down direction.

[0082] Next, the opening of the test pressure vessel, to which a medical cap 1 or the like was attached, was positioned downwards (i.e., the liquid-contacting surface of the elastic stopper faced upwards, and the needle-piercing surface faced downwards). A resin needle for an infusion set (outer diameter approximately φ5 mm, length approximately 26 mm) was then inserted into the injection hole of the elastic stopper. After standing for 24 hours with the needle inserted, the needle was removed, and the vessel was visually observed for 2 minutes to see if any leakage occurred from the downward-facing medical cap or the like. If leakage was observed, the amount of leakage (g) was also measured.

[0083] Puncture tests were performed on all medical caps, and the leakage rate (%) for each was calculated as ((number of samples with leakage) / (total number of samples) × 100). The results are shown in Tables 1 and 2. The evaluation criteria in Tables 1 and 2 were as follows: ○: No leakage △: Droplet present ×: Leakage present

[0084]

[0085]

[0086] As can be seen from Tables 1 and 2, when using the medical cap 100 of Comparative Example 1, the leakage rate was 100%. In contrast, the medical cap 1 of Example 1 had a leakage rate of 0%.

[0087] (Puncture test with spike needle) Ten medical caps 1 from Example 1 and ten medical caps 100 from Comparative Example 1 were prepared and fixed to a special jig. The special jig used was one that could fix the elastic stopper body in a state where the needle puncture surface and the liquid contact surface were exposed.

[0088] Next, a resin spiked needle was inserted into the recess of the needle-piercing surface of an elastic stopper body such as medical cap 1, which was fixed with a special jig. The spiked needle used had blade surfaces that intersect the direction of extension of the spiked needle and a sharply pointed tip, with an outer diameter of approximately 5.5 mm, a length of approximately 20 mm, and a blade surface angle of approximately 36°. The puncture test was performed by checking whether the entire blade surface of the spiked needle protruded from the wetted surface of the elastic stopper body and was visible. If the entire blade surface was visible, it was considered puncture possible, and if the entire blade surface was not visible, it was considered puncture impossible. The puncture rate (%) ((number of punctureable samples) / (total number of samples) × 100) was calculated for each case. The results are shown in Tables 3 and 4. The evaluation criteria in Tables 3 and 4 were as follows: ○: Puncture possible ×: Puncture impossible

[0089]

[0090]

[0091] As can be seen from Tables 3 and 4, the puncture success rate was 100% when using medical cap 1 of Example 1. In contrast, the puncture success rate was 0% when using medical cap 100 of Comparative Example 1.

[0092] 1, 1', 2, 3, 4... Medical cap, 10, 10'... Outer frame, 11, 41, 43, 46... Annular body, 11a... Outer wall, 11b... Inner wall, 11c... Notch, 11d... Slit, 11e... Connecting part, 11f, 11g, 11h, 11i... Engaging part, 12... Support part, 12a... Upper support part, 12b... Lower support part, 12c... Embedded part, 12d... Connecting part, 12e... Gate mark, 12f... Annular wall, 12g... Flange part, 12h... Engaging part, 12i... Groove, 20, 24... Elastic plug, 21... Needle puncture surface, 21a... Recess, 22... Fluid contact surface, 23, 25... Side circumference, 23a... Male tapered part, 23b... Stepped section, 26...Stepped section, 31...First upper mold (first mold), 31a, 33a...Runner, 31b...Molten resin injection gate, 32...Common lower mold (common mold), 32a...Groove section, 33...Second upper mold (second mold), 33b...Molten resin injection gate, 33c...Ring-shaped projection, 33d...Groove section, 42, 44, 47...Inner wall, 42a, 44a, 47a...First inner wall, 42b, 44b, 47b...Second inner wall, 42c, 44c, 47c...Third inner wall, 42d, 44d, 47d...Fourth inner wall, 45...Protruding section (locking section), 48...Protrusion (locking section), 51...Port member, 52...Cylindrical body, 53...Housing section, θ １ , θ ２ ...center angle

Claims

1. A medical cap comprising an elastic plug and an outer frame that holds the elastic plug inside, wherein the outer frame has an annular portion and a support portion, the annular portion has an inner wall that surrounds the side circumference of the elastic plug in a tightly fitted state, an outer wall that surrounds the inner wall, and at least one slit portion that crosses the inner wall longitudinally, the support portion has an upper support portion that supports the side circumference of the elastic plug from the upper side, a lower support portion that supports the side circumference of the elastic plug from the lower side, and at least one connecting portion that connects the upper support portion and the lower support portion, the inner wall is a downward-hanging wall that is connected to the inner surface of the outer wall at its upper end and whose wall surface hangs down with space between it and the outer wall, the lower support portion presses the side circumference of the elastic plug through the inner wall by being embedded between the inner wall and the outer wall. A medical cap in which the connecting portion has the slit portion embedded, the elastic plug is in close contact with the contact surface of the annular portion, and the support portion is welded to the contact surface of the elastic plug and the annular portion.

2. The medical cap according to claim 1, wherein a notch is provided at the lower end of the inner wall.

3. The medical cap according to claim 1, wherein the lower surface side of the circumferential portion of the elastic plug body is provided with a male tapered portion that gradually decreases in diameter towards the lower surface of the elastic plug body.

4. The medical cap according to claim 1, wherein, when the lower support portion is not embedded between the inner wall and the outer wall, the inner wall protrudes downward from the lower end surface of the outer wall.

5. The medical cap according to claim 1, wherein the inner wall surface is provided with a locking portion for locking the side circumference of the elastic plug body housed inside the inner wall.

6. A method for manufacturing a medical cap according to any one of claims 1 to 5, comprising: an annular body molding step of molding the annular body using a common mold and a first mold; a placement step of placing the elastic plug inside the annular body with its upper surface facing downward; and a support part molding step of molding the support part using the common mold and a second mold having a ring-shaped projection having a diameter smaller than the lower surface of the elastic plug, while pressing the peripheral edge of the lower surface of the elastic plug placed inside the annular body with the ring-shaped projection.

7. The method for manufacturing a medical cap according to claim 6, wherein the support molding step involves injecting molten resin for molding the support between the inner wall and the outer wall of the annular body to mold the support.

8. The medical cap according to claim 7, wherein the support molding step involves injecting the molten resin between the inner wall and the outer wall of the annular portion at the central position of the inner wall to form the support portion.

9. The method for manufacturing a medical cap according to claim 6, as dependent on claim 2, wherein the support molding step involves injecting molten resin for molding the support between the inner wall and the outer wall of the annular body at the position where the notch is provided to mold the support.

Images