Prefilled Syringes

Abstract

To provide a pre-filled syringe that can prevent liquid from leaking through a gap between a cylindrical container and a plunger in the state where the plunger has been pushed into the cylindrical container.SOLUTION: This pre-filled syringe 1 is provided with a cylindrical container 100, a front-end gasket 400, a rear-end gasket 500, an intermediate gasket 600, and a plunger 200. The cylindrical container 100 has an inner circumferential surface 112S, a protruding inner surface 114S, and a reception surface 122S. The intermediate gasket 600 has a groove 610 formed on the outer circumferential surface thereof. The plunger 200 has a connection section 230, a pressing section 220, and a guide rib 214. The protruding inner surface 114S is formed at a position that faces the pressing section 220 in a pushed-in state. The guide rib 214 has a recess 214a. The rear end 214b of the recess 214a is located behind the rear end 114b of the protruding inner surface 114S in the pushed-in state.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The present invention relates to a pre-filled syringe. [Background technology]

[0002] Conventionally, a prefilled syringe capable of mixing a drug and a drug solution in a container has been known. For example, International Publication No. 2015 / 079874 discloses a prefilled syringe including a cylindrical container, a front end gasket, a rear end gasket, an intermediate gasket, and a plunger. Each gasket is slidable in the cylindrical container. A drug is contained in a front chamber formed between the front end gasket and the intermediate gasket in the cylindrical container, and a liquid drug is contained in a rear chamber formed between the rear end gasket and the intermediate gasket in the cylindrical container. The plunger is connected to the rear end gasket and can push the rear end gasket toward the front end. The cylindrical container has a bypass portion protruding radially outward. A groove is formed on the outer circumferential surface of the intermediate gasket at a position where the intermediate gasket faces the bypass portion, which connects the front chamber and the rear chamber.

[0003] When the plunger is not pressed, the intermediate gasket is located rearward of the bypass portion, and the front and rear chambers are partitioned by the intermediate gasket. When the plunger is pressed and the intermediate gasket faces the bypass portion, the front and rear chambers are connected, and the liquid moves toward the front chamber through the groove of the intermediate gasket by being pushed by the rear gasket. This causes the drug and the liquid to mix. When the plunger is further pressed from this state, the front gasket is pushed forward until the front end of the front gasket comes into contact with the bottom surface of the nozzle portion, and when the plunger is further pressed, the mixture of the drug and the liquid is discharged through the gap between the front gasket and the nozzle portion. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. 2015 / 079874 Summary of the Invention [Problem to be solved by the invention]

[0005] In the prefilled syringe described in WO 2015 / 079874, when the plunger has been completely pushed into the cylindrical container (the front gasket is in contact with the bottom surface of the nozzle, the intermediate gasket is in contact with the front gasket, and the rear gasket is in contact with the intermediate gasket), if the rear end of the rear gasket is set in a position facing the bypass, there is a risk that the liquid or mixed liquid remaining in the bypass will leak out to the rear end of the cylindrical container through the gap between the cylindrical container and the plunger due to capillary action.

[0006] An object of the present invention is to provide a prefilled syringe that can suppress leakage of liquid through the gap between a cylindrical container and a plunger when the plunger has been completely pushed into the cylindrical container. [Means for solving the problem]

[0007] A prefilled syringe according to one aspect of the present invention is capable of containing a medicinal liquid and a drug, and comprises a cylindrically formed cylindrical container; a front end gasket that is provided within the cylindrical container and is slidable relative to the cylindrical container along the axial direction of the cylindrical container; a rear end gasket that is provided behind the front end gasket within the cylindrical container so as to define a space within the cylindrical container together with the front end gasket, and is slidable relative to the cylindrical container along the axial direction of the cylindrical container; and the space is defined by a front chamber that contacts the front end gasket and a rear end gasket that contacts the rear end gasket. and a plunger connected to the rear end gasket and capable of pressing the rear end gasket toward the front end of the cylindrical container along the axial direction. The cylindrical container has an inner circumferential surface in contact with an outer circumferential surface of the front gasket, an outer circumferential surface of the intermediate gasket, and an outer circumferential surface of the rear end gasket, and a plunger protruding from the inner circumferential surface in a direction perpendicular to the axial direction. The intermediate gasket has a protruding inner surface having a shape extending along the axial direction, and a receiving surface for receiving the front gasket in the axial direction, and a groove is formed on the outer circumferential surface of the intermediate gasket at a position where the intermediate gasket faces the protruding inner surface, which communicates the front chamber with the rear chamber, and the plunger has a connection portion connected to the rear end gasket, a pressing portion that presses the rear end gasket, and is formed in a flat plate shape extending from the pressing portion along the axial direction of the cylindrical container and along a plane including a central axis of the cylindrical container, and a groove is formed on the outer circumferential surface of the intermediate gasket at a position where the intermediate gasket faces the protruding inner surface, which communicates the front chamber with the rear chamber, and the plunger has a connection portion connected to the rear end gasket, a pressing portion that presses the rear end gasket, and a pressing portion that presses the rear end gasket. and a guide rib for guiding movement of the plunger along the cylindrical container, the protruding inner surface being formed at a position facing the pressing portion in a pushing-completed state in which the leading end gasket is in contact with the receiving surface, the intermediate gasket is in contact with the leading end gasket, and the plunger is pushed into the cylindrical container until the rear end gasket is in contact with the intermediate gasket, the guide rib having a recess having a shape recessed toward the central axis so as to be spaced away from the inner peripheral surface of the cylindrical container, and a rear end portion of the recess in the axial direction is such that in the pushing-completed state:The protruding inner surface is located rearward of the rear end portion of the protruding inner surface in the axial direction. Effect of the Invention

[0008] According to the present invention, it is possible to provide a prefilled syringe that can suppress leakage of liquid through the gap between the cylindrical container and the plunger when the plunger has been completely pushed into the cylindrical container. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a perspective view of a pre-filled syringe according to one embodiment of the present invention. [Diagram 2] FIG. 1 is a cross-sectional view of a prefilled syringe. [Diagram 3] FIG. [Figure 4] FIG. [Diagram 5] 3 is an enlarged view of the area indicated by the solid line V in FIG. 2. [Figure 6] FIG. 11 is a cross-sectional view showing a state in which pushing is completed. [Figure 7] FIG. 7 is an enlarged view of the area indicated by solid line VII in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described with reference to the accompanying drawings, in which the same or corresponding components are designated by the same reference numerals.

[0011] FIG. 1 is a perspective view of a prefilled syringe according to an embodiment of the present invention. FIG. 2 is a cross-sectional view of the prefilled syringe. This prefilled syringe 1 has a function as a container for a medicinal liquid 10 and a drug 20, and a function as a syringe. As shown in FIG. 1 and FIG. 2, the prefilled syringe 1 includes a medicinal liquid 10, a drug 20, a cylindrical container 100, a plunger 200, an injection needle unit 300, a front end gasket 400, a rear end gasket 500, an intermediate gasket 600, and a cap 700. Note that FIG. 1 and FIG. 2 show the prefilled syringe 1 before use.

[0012] The cylindrical container 100 contains the drug solution 10 and the drug 20 in a state where the drug solution 10 and the drug 20 are separated from each other. In other words, the cylindrical container 100 functions as a container for the drug solution 10 and the drug 20. The cylindrical container 100 has a barrel 110, a nozzle portion 120, and a flange portion 130.

[0013] The barrel 110 contains the drug solution 10 and the drug substance 20. As shown in Fig. 2, the front end (the upper end in Fig. 2) and the rear end (the lower end in Fig. 5) of the barrel 110 are open. The barrel 110 has a barrel body 112 and a protruding portion 114.

[0014] The barrel body 112 is formed in a cylindrical shape. A stop ring R is provided on the barrel body 112. The stop ring R indicates the amount of depression of the plunger 200 into the cylindrical container 100.

[0015] The protruding portion 114 has a shape that bulges outward from the barrel body 112 in the radial direction of the barrel body 112 and extends along the axial direction of the barrel body 112 (the vertical direction in FIG. 2). The inner surface of the protruding portion 114 constitutes a protruding inner surface 114S (see FIG. 2). The protruding inner surface 114S has a shape that protrudes from the inner peripheral surface 112S of the barrel body 112 in a direction perpendicular to the axial direction and extends along the axial direction.

[0016] The nozzle portion 120 is connected to the tip portion of the barrel body 112. The nozzle portion 120 has a storage portion 122, a rib 124, an attachment portion 126, and a discharge portion 128.

[0017] The storage section 122 is capable of storing the tip gasket 400. The storage section 122 is located on the tip side of the barrel body 112. A flow path 122f for discharging a mixture of the drug solution 10 and the drug 20 is formed on the inner surface of the storage section 122. This flow path 122f has a shape that is recessed from a portion of the inner surface of the storage section 122 other than the flow path 122f. The storage section 122 has a receiving surface 122S that receives the tip gasket 400 in the axial direction. As shown in FIG. 1, a protective member 800 is attached to the storage section 122.

[0018] The ribs 124 are provided at positions different from the flow paths 122f on the inner circumferential surface of the accommodating portion 122. The ribs 124 protrude radially inward from the inner circumferential surface of the accommodating portion 122 and extend along the axial direction. The ribs 124 are provided at equal intervals along the circumferential direction of the accommodating portion 122.

[0019] The attachment portion 126 is a portion that is attached to the tip end of the barrel main body 112. The attachment portion 126 has a shape that extends rearward from the rear end portion of the accommodating portion 122. The attachment portion 126 is formed in a cylindrical shape.

[0020] The discharge part 128 has a shape extending forward from the tip of the storage part 122. The inside of the discharge part 128 is connected to the flow path 122f.

[0021] The injection needle unit 300 is connected to the discharge part 128. The injection needle unit 300 has a base 310 connected to the discharge part 128 and a puncture needle 320 held by the base 310. Before the prefilled syringe 1 is used as a syringe, the puncture needle 320 is covered with a cap 700 (see FIG. 1).

[0022] The flange portion 130 is connected to the rear end portion of the barrel body 112. The flange portion 130 has a mounting tubular portion 132, a protruding portion 134, and a contact portion 136.

[0023] The mounting cylinder portion 132 is a portion that is attached to the rear end portion of the barrel main body 112. The mounting cylinder portion 132 is formed in a cylindrical shape.

[0024] The protruding portion 134 has a shape that protrudes radially outward from the rear end portion of the mounting tube portion 132 .

[0025] The abutment portion 136 is connected to an inner end of the protruding portion 134 in the radial direction.

[0026] The tip gasket 400 is provided in the cylindrical container 100. Specifically, the tip gasket 400 is housed in the barrel body 112 on the tip side of the protruding portion 114 before use of the prefilled syringe 1. The tip gasket 400 is in close contact with the inner circumferential surface 112S of the barrel body 112. The tip gasket 400 is slidable with respect to the barrel body 112 and the storage portion 122 along the axial direction. As shown in FIG. 6, when the tip surface 400S of the tip gasket 400 is in contact with the receiving surface 122S of the storage portion 122, the tip gasket 400 is detached from the barrel body 112. In this state, the mixed liquid is discharged through the flow path 122f.

[0027] The rear end gasket 500 is provided behind the front end gasket 400 in the cylindrical container 100 so as to define a space in the cylindrical container 100 together with the front end gasket 400. The rear end gasket 500 is in close contact with the inner circumferential surface 112S of the barrel body 112. The rear end gasket 500 is slidable relative to the barrel body 112 along the axial direction. As shown in FIG. 5, the rear end gasket 500 has a female screw portion 510 formed therein.

[0028] The intermediate gasket 600 is provided between the front end gasket 400 and the rear end gasket 500 in the barrel body 112 of the cylindrical container 100 so as to divide the space into a front chamber and a rear chamber. As shown in Fig. 2, the intermediate gasket 600 is accommodated in the barrel body 112 on the rear end side of the protruding portion 114 before use of the prefilled syringe 1.

[0029] The front chamber is a space in contact with the tip gasket 400. More specifically, the front chamber is a space defined by the tip gasket 400, the intermediate gasket 600, and the barrel 110. The drug 20 is contained in the front chamber.

[0030] The rear chamber is a space in contact with the rear end gasket 500. More specifically, the rear chamber is a space defined by the rear end gasket 500, the intermediate gasket 600, and the barrel 110. The medicinal liquid 10 is contained in the rear chamber.

[0031] The intermediate gasket 600 is in close contact with the inner peripheral surface 112S of the barrel body 112. The intermediate gasket 600 is slidable relative to the barrel body 112 along the axial direction. A groove 610 that connects the front chamber and the rear chamber is formed on the outer peripheral surface of the intermediate gasket 600 at a position where the intermediate gasket 600 faces the protruding inner surface 114S.

[0032] The plunger 200 is connected to the rear end gasket 500. The plunger 200 can press the rear end gasket 500 toward the tip side of the cylindrical container 100 along the axial direction. As shown in FIG. 3 and FIG. 4, the plunger 200 has an axis portion 210, a pressing portion 220, and a connecting portion 230.

[0033] The connecting portion 230 is connected to the rear end gasket 500. The connecting portion 230 has a male thread portion that screws into the female thread portion 510 of the rear end gasket 500.

[0034] The pressing portion 220 is connected to the rear end portion of the connecting portion 230. The pressing portion 220 presses the rear end gasket 500. The pressing portion 220 is formed in a disk shape.

[0035] Fig. 6 is a cross-sectional view in a pushing-completed state (a state in which the leading end gasket 400 contacts the receiving surface 122S, the intermediate gasket 600 contacts the leading end gasket 400, and the plunger 200 is pushed into the cylindrical container 100 until the rear end gasket 500 contacts the intermediate gasket 600). Fig. 7 is an enlarged view of the area indicated by the solid line VII in Fig. 6.

[0036] 6 and 7, the pressing portion 220 faces the protruding inner side surface 114S in the pressed-in state. In other words, the protruding inner side surface 114S is formed at a position facing the pressing portion 220 in the pressed-in state.

[0037] The shaft portion 210 has a shape that extends rearward from the rear end surface of the pressing portion 220 along the axial direction of the barrel 110. The shaft portion 210 has a cylindrical portion 212 and a guide rib 214.

[0038] The guide rib 214 guides the movement of the pressing portion 220 along the axial direction relative to the barrel 110. The guide rib 214 extends rearward from the pressing portion 220 along the axial direction, and is formed in a flat plate shape along a plane including the central axis of the cylindrical container 100. In this embodiment, the plunger 200 has four guide ribs 214. The guide ribs 214 are arranged at 90 degree intervals around the central axis. The cylindrical portion 212 is connected to the rear end of the guide rib 214.

[0039] The guide rib 214 has a recess 214a. The recess 214a has a shape recessed toward the central axis so as to be spaced away from the inner circumferential surface 112S of the barrel body 112 of the cylindrical container 100. As shown in Fig. 7, the rear end 214b of the recess 214a in the axial direction is located rearward of the rear end 114b of the protruding inner surface 114S in the axial direction in the push-in complete state. That is, in the push-in complete state, a predetermined distance L is ensured between the rear end 114b of the protruding inner surface 114S and the rear end 214b of the recess 214a.

[0040] 5, in a state in which the plunger 200 is not pressed (a state in which the pressing portion 220 is not pressing the rear end gasket 500), the contact portion 136 abuts against a portion of the guide rib 214 that is closer to the rear end side than the recessed portion 214a in the axial direction. The contact portion 136 is preferably formed in an annular shape.

[0041] Next, a method of using the prefilled syringe 1 will be described.

[0042] First, the attitude of the prefilled syringe 1 is adjusted so that the injection needle unit 300 faces upward as shown in Fig. 2. In this state, the plunger 200 is pushed upward into the cylindrical container 100.

[0043] When the groove 610 of the intermediate gasket 600 faces the protruding inner surface 114S, the front chamber and the rear chamber communicate with each other, so that the drug solution 10 in the rear chamber moves toward the front chamber through the gap between the groove 610 of the intermediate gasket 600 and the protruding inner surface 114S by being pushed by the rear end gasket 500. This causes the drug solution 10 and the drug 20 to mix. At this time, the plunger 200 is pushed in until the tip surface 600S of the intermediate gasket 600 coincides with the stop ring R (see Figures 1 and 2). In this state, a part of the tip gasket 400 is located in the storage section 122, and the tip surface 400S of the tip gasket 400 is separated from the receiving surface 122S.

[0044] With the tip surface 600S of the intermediate gasket 600 aligned with the stop ring R, tapping or the like is performed, and then the plunger 200 is further pushed in. Then, the tip gasket 400 is released from the barrel body 112, and the tip surface 400S of the tip gasket 400 comes into contact with the receiving surface 122S. By further pushing the plunger 200 from that state, the mixed liquid is discharged through the flow path 122f and the puncture needle 320. Then, when the pushing-completed state shown in Figs. 6 and 7 is reached, the discharge of the mixed liquid is completed.

[0045] In this prefilled syringe 1, in the pushed-in state, a part of the drug solution 10 or the mixed solution may remain in the protruding portion 114 or the pressing portion 220. However, in the prefilled syringe 1 of this embodiment, in the pushed-in state, the rear end 214b of the recess 214a is located behind the rear end 114b of the protruding inner surface 114S, so that the distance L from the protruding inner surface 114S to the gap between the part of the guide rib 214 behind the recess 214a and the inner circumferential surface 112S of the barrel body 112 is secured. Therefore, liquid leakage through the gap between the cylindrical container 100 and the plunger 200 in the pushed-in state is suppressed.

[0046] [Aspects] It will be appreciated by those skilled in the art that the exemplary embodiments described above are examples of the following aspects.

[0047] A prefilled syringe according to one aspect of the disclosure is capable of containing a medicinal liquid and a drug, and includes a cylindrically formed cylindrical container; a front end gasket that is provided within the cylindrical container and is slidable relative to the cylindrical container along the axial direction of the cylindrical container; a rear end gasket that is provided behind the front end gasket within the cylindrical container so as to define a space within the cylindrical container together with the front end gasket, and is slidable relative to the cylindrical container along the axial direction of the cylindrical container; and the space includes a front chamber that contacts the front end gasket and a rear end gasket that contacts the rear end gasket. and a plunger connected to the rear end gasket and capable of pressing the rear end gasket toward the front end of the cylindrical container along the axial direction. The cylindrical container has an inner circumferential surface in contact with an outer circumferential surface of the front gasket, an outer circumferential surface of the intermediate gasket, and an outer circumferential surface of the rear end gasket, and a plunger protruding from the inner circumferential surface in a direction perpendicular to the axial direction. The intermediate gasket has a protruding inner surface having a shape extending along the axial direction, and a receiving surface for receiving the front gasket in the axial direction, and a groove is formed on the outer circumferential surface of the intermediate gasket at a position where the intermediate gasket faces the protruding inner surface, which communicates the front chamber with the rear chamber, and the plunger has a connection portion connected to the rear end gasket, a pressing portion that presses the rear end gasket, and is formed in a flat plate shape extending from the pressing portion along the axial direction of the cylindrical container and along a plane including a central axis of the cylindrical container, and a groove is formed on the outer circumferential surface of the intermediate gasket at a position where the intermediate gasket faces the protruding inner surface, which communicates the front chamber with the rear chamber, and the plunger has a connection portion connected to the rear end gasket, a pressing portion that presses the rear end gasket, and a pressing portion that presses the rear end gasket. and a guide rib for guiding movement of the plunger along the cylindrical container, the protruding inner surface being formed at a position facing the pressing portion in a pushing-completed state in which the leading end gasket is in contact with the receiving surface, the intermediate gasket is in contact with the leading end gasket, and the plunger is pushed into the cylindrical container until the rear end gasket is in contact with the intermediate gasket, the guide rib having a recess having a shape recessed toward the central axis so as to be spaced away from the inner peripheral surface of the cylindrical container, and a rear end portion of the recess in the axial direction is such that in the pushing-completed state:The protruding inner surface is located rearward of the rear end portion of the protruding inner surface in the axial direction.

[0048] In this prefilled syringe, in the fully pushed-in state, the rear end of the recess is located behind the rear end of the protruding inner surface, so that the distance from the protruding inner surface to the gap between the cylindrical container and the portion of the guide rib behind the recess is secured, thereby suppressing liquid leakage through the gap between the cylindrical container and the plunger in the fully pushed-in state.

[0049] The cylindrical container preferably has an abutment portion that abuts against a portion of the guide rib that is further rearward than the recess in the axial direction when the pressing portion is not pressing against the rear end gasket.

[0050] This reduces rattling of the plunger relative to the cylindrical container when the pressing portion is not pressing against the rear end gasket.

[0051] It is also preferable that the device further comprises a medicine contained in the front chamber and a medicinal liquid contained in the rear chamber.

[0052] It should be noted that the embodiments disclosed herein are illustrative in all respects and should not be considered as limiting. The scope of the present invention is indicated by the claims, not by the description of the embodiments above, and further includes all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0053] 1 Prefilled syringe, 10 Drug solution, 20 Drug, 100 Cylindrical container, 110 Barrel, 112 Barrel body, 112S Inner peripheral surface, 114 Protruding portion, 114S Protruding inner surface, 114b Rear end, 120 Nozzle portion, 122 Storage portion, 122S Receiving surface, 122f Flow path, 124 Rib, 126 Mounting portion, 128 Discharge portion, 130 Flange portion, 132 Mounting tube portion, 134 Protruding portion, 136 Abutment portion, 200 Plunger, 210 Shaft portion, 212 Cylindrical portion, 214 Guide rib, 214a Recess, 214b Rear end, 220 Pressing portion, 230 Connection portion, 300 Injection needle unit, 310 Base body, 320 Puncture needle, 400 Tip gasket, 500 Rear end gasket, 510 female thread, 600 mid gasket, 610 groove, 700 cap, 800 protective member.

Claims

1. A cylindrical container capable of containing a medicinal solution and a drug, the cylindrical container being formed in a cylindrical shape; a tip gasket provided in the cylindrical container and slidable relative to the cylindrical container along an axial direction of the cylindrical container; a rear end gasket provided in the cylindrical container rearward of the front end gasket so as to define a space within the cylindrical container together with the front end gasket, the rear end gasket being slidable relative to the cylindrical container along the axial direction of the cylindrical container; an intermediate gasket provided between the front end gasket and the rear end gasket in the cylindrical container so that the space is divided into a front chamber in contact with the front end gasket and a rear chamber in contact with the rear end gasket, the intermediate gasket being slidable relative to the cylindrical container along the axial direction of the cylindrical container; a plunger connected to the rear end gasket and capable of pressing the rear end gasket toward a front end side of the cylindrical container along the axial direction, The cylindrical container comprises: an inner circumferential surface in contact with an outer circumferential surface of the front end gasket, an outer circumferential surface of the intermediate gasket, and an outer circumferential surface of the rear end gasket; a protruding inner surface protruding from the inner circumferential surface in a direction perpendicular to the axial direction and extending along the axial direction; a receiving surface for receiving the tip gasket in the axial direction, a groove is formed on an outer circumferential surface of the intermediate gasket at a position where the intermediate gasket faces the protruding inner surface, the groove connecting the front chamber and the rear chamber; The plunger is a connection portion connected to the rear end gasket; a pressing portion that presses the rear end gasket; a guide rib extending from the pressing portion along the axial direction of the cylindrical container and formed in a flat plate shape along a plane including a central axis of the cylindrical container, the guide rib guiding movement of the pressing portion along the axial direction, the protruding inner surface is formed at a position facing the pressing portion in a pushing-completed state in which the plunger is pushed into the cylindrical container until the leading end gasket contacts the receiving surface, the intermediate gasket contacts the leading end gasket, and the rear end gasket contacts the intermediate gasket, the guide rib has a recess having a shape recessed toward the central axis so as to be spaced apart from the inner circumferential surface of the cylindrical container, a prefilled syringe, in which, in the pushed-in state, a front end of the pressing portion and the recess in the axial direction face the protruding inner surface, and a rear end of the recess in the axial direction is located rearward of a rear end of the protruding inner surface in the axial direction.

2. The prefilled syringe according to claim 1, wherein the cylindrical container has an abutment portion that abuts against a portion of the guide rib that is further rearward than the recess in the axial direction when the pressing portion is not pressing against the rear end gasket.

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