WO2022202887A1

WO2022202887A1 - Syringe

Info

Publication number: WO2022202887A1
Application number: PCT/JP2022/013426
Authority: WO
Inventors: 克則大西
Original assignee: 構法開発株式会社
Priority date: 2021-03-26
Filing date: 2022-03-23
Publication date: 2022-09-29
Also published as: JPWO2022202887A1

Abstract

The syringe of the present invention is configured from an outer cylinder provided with a cylinder tip having a small hole at one end and an open portion at the other end, a gasket provided hermetically sealably and slidably within the outer cylinder, and a plunger connected to the gasket, the syringe characterized in that a layer of a deformable material that can be freely deformed by external pressure is provided on the cylinder tip side surface of the gasket. This makes it possible to provide a syringe capable of keeping residual drug solution to a minimum when a drug solution has been ejected.

Description

Syringe

The present invention relates to a syringe, and more specifically to a syringe used for injection of vaccines and the like.

Conventionally, as a syringe for medical use, an outer cylinder 2 having a tip 21 having a hole at one end and an opening 22 at the other end, as shown in FIG. 10(A), and the outer cylinder A syringe 1 is used which is composed of a gasket 3 provided so as to be able to seal and slide inside the syringe 2 and a plunger 4 connected to the gasket 3 .

The syringe 1 having the above-described conventional structure is generally widely used. Thus, a space 23 and a space 62 in the needle tube are generated between the pore of the tube tip 21 provided at the tip of the plunger 4 and the gasket 3, and the contents such as the drug solution remain in the

spaces

23 and 62. , the chemical solution 8 and the like cannot be completely ejected.

In particular, when the content is a drug solution such as a vaccine that is expensive and consumed in large quantities, even if the amount of drug solution remaining in one syringe is small, the total waste amount when a large amount is used is There is a problem that a large amount is required, and as a result, the cost for one injection becomes relatively high.

In response to such problems, syringes have been proposed that have a structure in which the liquid medicine is less likely to remain inside the outer cylinder when the liquid medicine inside the syringe is injected (see Patent Documents 1 and 2). The proposed syringe is said to be capable of suppressing the residual of the liquid medicine by providing a protrusion that fits into the tip of the cylinder on the side of the gasket that extrudes the liquid medicine, thereby reducing the space in which the liquid medicine remains.

Japanese Patent Publication No. 2001-523986 Japanese Patent Application Laid-Open No. 2020-150998

However, in the syringes proposed in

Patent Documents

1 and 2, high dimensional accuracy is required because the protrusion provided at the tip of the gasket needs to be securely fitted to the barrel tip. Since a separate design is required, there is a problem that the cost is very high. In addition, although the space at the tip of the barrel can be eliminated to some extent by fitting the projections, a gap is required between the projections in order to push out the drug solution in the cylinder at the same time, and the space between the gaps, the needle mounting portion, and the needle tube. There was also a problem that the chemical solution remained in the part as before.

The present invention has been made in view of the circumstances as described above, and provides a syringe that can be applied to conventional syringes and that can minimize the amount of residual liquid medicine when the liquid medicine is injected. The challenge is to

The syringe of the present invention has been made to solve the above technical problems, and has the following features.
First, the syringe of the present invention comprises an outer cylinder having a tip with a hole at one end and an opening at the other end, and a gasket provided so as to seal and slide inside the outer cylinder. and a plunger connected to the gasket,
The gasket is characterized in that a layer of a deformable material whose shape can be freely deformed by an external pressure is provided on the surface of the gasket on the tube tip side.
Secondly, in the syringe of the first invention, it is preferable that the deformable material is a gel-like substance that is difficult to dissolve in the contents of the syringe.
Third, in the syringe of the first or second invention, it is preferable that the deformable material is any one of a gel-like substance, a gel-like substance, a clay-like substance, and a gummy-like substance.
Fourthly, in the syringes of the first to third inventions, the volume of the deformable material pushes the plunger of the syringe, which is not provided with the deformable material, toward the tip of the syringe. is preferably equal to the volume of
Fifth, in the syringe of the fourth aspect of the invention, it is preferable that the volume of the deformable material includes the volume of the space inside the needle tube when the injection needle is attached to the syringe.
Sixthly, in the syringe of the first invention, it is preferable that the deformable material is gas.
Seventhly, in the syringe of the sixth invention, it is preferable that the syringe has a volume of 1 mL or less and the volume of the gas is 0.07 mL or less.
Eighth, in the syringes of the first to seventh inventions, it is preferable that the syringe is a prefilled syringe.

According to the syringe of the present invention, it is possible to apply it to a conventional syringe, and it is possible to suppress the residual of the liquid medicine as much as possible when the liquid medicine is injected.

It is a schematic sectional drawing which shows the syringe of this invention. FIG. 4 is a schematic cross-sectional view showing procedures (A) to (F) of the method of introducing a deformable material into the syringe of the present invention; FIG. 4 is a schematic cross-sectional view showing procedures (A) to (D) of another method of introducing a deformable material into the syringe of the present invention; FIG. 4 is a schematic cross-sectional view showing procedures (E) to (H) of another method of introducing a deformable material into the syringe of the present invention; FIG. 2 is a schematic cross-sectional view showing procedures (A) to (E) of a method for introducing a drug solution into the syringe of the present invention; FIG. 10 is a photograph showing how the air layer is fixed to the gasket in a syringe provided with an air layer as a deformable material. FIG. FIG. 4 is a schematic cross-sectional view showing procedures (A) to (D) of a method for introducing an air layer as a deformable material into the syringe of the present invention. FIG. 4 is a schematic cross-sectional view showing procedures (A) to (C) for injecting a drug solution with the syringe of the present invention. FIG. 4 is a schematic cross-sectional view showing procedures (D) to (F) for injecting a drug solution with the syringe of the present invention; (A) is a schematic cross-sectional view showing a conventional syringe, and (B) is a schematic cross-sectional view showing a state in which the plunger of the syringe of (A) has been completely pushed.

The embodiment of the syringe of the present invention will be described in detail below based on the drawings. The syringe of this embodiment, as shown in FIG. It is composed of a slidable gasket 3 and a pusher 4 connected to the gasket 3 . A layer of a deformable material 5 whose shape can be freely deformed by external pressure is provided on the surface of the gasket 3 on the tube tip 21 side.

In the syringe 1 of the present invention, a layer of the deformable material 5 is provided on the surface of the gasket 3 of the conventional syringe on the tip 21 side, so that the deformable material 5 enters and buries the portion where the conventional drug solution remains after injection, thereby burying the drug solution. It becomes possible to almost eliminate the residue of 8.

The deformable material 5 in the syringe 1 of the present embodiment is a substance that can be freely deformed in shape by external pressure. This deforms freely at least at room temperature and normal pressure, does not adversely affect the human body, and It is not particularly limited as long as it does not affect the effect of the content 8 when it comes into contact with the content 8, such as a chemical solution, and is not easily dissolved in the content 8. For example, gel substances, Solids and semi-solids such as gel-like substances, clay-like substances and gummy-like substances can be used. Specifically, examples of gel-like substances and gel-like substances include purified gelatin and purified sodium hyaluronate, and examples of clay-like substances and gummy-like substances include silicone rubber and polyisoprene as elastomers. can do. In the present invention, normal temperature and normal pressure means a range of 10 to 30° C. and 1000 Pa to 1050 Pa.

In addition, in the syringe 1 of the present embodiment, as described above, the plunger 4 of the syringe 1 without the deformable material 5 is pushed all the way to the barrel tip 21 side, and the space 23 existing in the syringe 1 is accurately adjusted. The volume of the deformable material 5 is preferably equal to the volume of the space 23 that occurs within the syringe 1 as it needs to penetrate.

Also, when using the syringe 1, the injection needle 6 is attached to the barrel tip 21, so strictly speaking, it is more preferable to consider the volume of the space 62 inside the needle tube 61 of the injection needle 6. That is, the volume of the deformable material 5 is preferably the sum of the volume of the space 23 inside the syringe 1 and the volume of the space 62 inside the needle tube 61 .

The deformable material 5 is formed on the surface of the gasket 3 on the tube tip 21 side, but the forming method is not particularly limited. It may be formed by sucking a predetermined amount with the syringe 1 .

As a method of directly adhering to the surface of the gasket 3, a predetermined volume of the deformable material 5 is sucked into another syringe or the like, and the deformable material 5 is ejected from the other syringe and adhered to the surface of the gasket 3. can be exemplified. Moreover, as another method of directly attaching the deformation material 5 to the surface of the gasket 3, a method of attaching the deformation material 5 to the gasket 3 using a case jig prepared by setting a predetermined volume of the deformation material 5 in the case is exemplified. can do. Furthermore, as a method of sucking with the syringe 1, for example, a method of sucking and forming the deformable material 5 in the vial 7 with a normal syringe 1 attached with a needle can be exemplified.

The procedure for forming a layer of the deformable material 5 on the gasket 3 using a case jig containing the deformable material will be described below with reference to FIG. The case jig 50 used in this method comprises a cylindrical case body 51 , a back cover 52 closing one side of the case body 51 , and a predetermined volume of the deformable material 5 disposed inside the case body 51 . ing. The case body 51 is formed in a shape that allows the gasket 3 to be fitted without a gap. It is designed so that it can be fixed to Here, the deformable material 5 used in this method is preferably a material that can hold a specific shape by itself and can be deformed by an external force. Further, in order to fix the deformable material 5 to the gasket 3 more reliably, an adhesive layer may be provided on the gasket 3 contact surface of the deformable material 5 .

First, the case jig 50 and the normal syringe 1 are prepared in advance (Fig. 2(A)). Next, the pusher 4 is pulled out from the syringe 1, the gasket 3 is taken out, the gasket 3 is fitted into the case body 51 of the case jig 50, and pressed against the deformation material 5 in the case jig 50 (Fig. 2(B)). ). Next, in this state, the back cover 52 of the case jig 50 is removed (FIG. 2(C)), and the case body 51 of the case jig 50 is attached to the opening 22 of the outer cylinder 2 (FIG. 2(D)). , the pusher 4 is pushed as it is, and the gasket 3 to which the deformable material 5 is fixed is inserted into the outer cylinder 2 of the syringe 1 (FIG. 2(E)). After pushing the gasket 3 into place, the case body 51 is removed (FIG. 2(F)). The syringe 1 of the present invention can be completed through the series of procedures described above.

Next, the procedure for forming a layer of the deformable material 5 by sucking the deformable material 5 in the vial 7 will be described step by step with reference to FIGS. 3 and 4. FIG. The deformable material 5 used in this method is preferably a gel or a gel-like substance because the deformable material 5 must be directly sucked with the syringe 1 . First, an injection needle 6 of the same type as the injection needle used for injecting the drug solution is attached to an ordinary syringe and prepared (Fig. 3(A)). is pressed (Fig. 3(B)). If the deformable material 5 is a substance that softens when heated, it can be handled well by heating it to a predetermined temperature.

Next, the pusher 4 is pulled and sucked so that the amount of the deformable material 5 is larger than the predetermined amount (Fig. 3(C)), and the pusher 4 is pushed out (Fig. 3(D) - FIG. 4(E)). Then, the injection needle 6 is pulled out from the vial 7, or the air is released after the injection needle 6 is pulled out from the vial 7, and the plunger 4 is pushed out (Fig. 4(F)). Next, the pusher 4 is pulled to move the deformable material 5 accumulated in the needle tube and the needle tip space into the outer cylinder 2 . At this time, it is preferable to vibrate the syringe 1 from below. Also, if it is heated to a predetermined temperature, it will be easier to move. At this time, air also enters the outer cylinder 2 (FIG. 4(G)). Next, the injection needle 6 is removed and the deformable material 5 is flattened by, for example, vibrating the outer cylinder 2 (FIG. 4(H)). The syringe 1 of the present invention can be completed through the series of procedures described above.

Next, a preparation procedure for introducing the drug 8 into the syringe 1 of the present invention and making it ready for injection will be described with reference to FIGS. 5(A) to 5(E). First, a syringe 1 of the present invention is prepared by attaching an injection needle 6 (Fig. 5(A)), inserting this into a vial 7 containing a medicine 8, and pushing a pusher 4 (Fig. 5(B)). . At this time, it should be noted that the deformable material 5 does not enter the space of the tip 21 . Next, the plunger 4 is pulled to introduce the drug 8 into the outer cylinder 2 so that the amount of the drug 8 is larger than the specified amount (Fig. 3(C)). (Fig. 3(D)). Then, the injection needle 6 is pulled out from the vial 7 (Fig. 5(E)). Introduction of the drug 8 into the syringe 1 of the present invention can be completed by the above series of procedures.

In addition, in the syringe 1 of the present invention, gas can be used in addition to the solid matter and semi-solid matter in the above embodiments as the deformable material provided on the barrel tip side surface of the gasket 3 . That is, in a state where the syringe 1 is filled with the drug solution 8, the gas layer 53 can be provided on the surface of the gasket 3 on the tube tip side.

When the gas layer 53 is provided on the surface of the gasket 3, in order to prevent the gas 53 from being injected, the gas layer 53 having a volume less than the volume of the space 23 (dead space) of the syringe 1 is reliably formed by surface tension. It must be fixed to the gasket 3. Therefore, with regard to the syringe 1 of this embodiment, the dead space present in the syringe 1 is limited to a syringe with a specific volume.

As the syringe 1 in which the gas layer 53 can be stably fixed by surface tension, in the case of a general needleless syringe (luer type, luer lock type), tuberculin tuberculin with an outer cylinder inner diameter of 5 mm or less and a volume of 1 mL or less. A syringe is preferred.

The volume of the gas layer 53 provided on the surface of the gasket 3 when the chemical solution 8 is injected when the syringe 1 under the above conditions is used can be obtained from the following calculation. For example, in an environment with a temperature of 20° C. (293 K) and an atmospheric pressure of 1013 hPa, the gas 53 and the drug solution 8 are injected into the syringe 1, and the room temperature at the time of injection is ±8° C. (12° C. to 28° C.) and the atmospheric pressure is ±25 hPa (988 ~ 1038 hPa), when the room temperature and pressure difference are in the range of normal distribution 3σ,
Thermal expansion coefficient: (8 3/4 + 293) / 293 x barometric expansion coefficient: (25 3 / 4 + 1013) / 1013 = 1.0393661, V: 0.073 mL / 1.0393661 = 0.0702351
Therefore, the space existing in the syringe 1 under the above conditions is calculated to be approximately 0.07 mL. From the above point of view, it is considered that the volume of the gas layer 53 provided on the surface of the gasket 3 is 0.07 mL or less. Further, the shape in which the gas 53 stably settles on the surface of the gasket 3 inside the syringe is a spherical bubble.

The following shows an experiment that confirmed the fixation state of the gas layer 53 to the gasket 3 when the gas layer 53 with a volume of 0.07 mL was provided on the gasket 3 of a thin tuberculin syringe.

A thin tuberculin syringe with an inner diameter of 4.6 mm and a volume of 1 mL was filled with blue water and air as the chemical solution 8 . The gas 53 was filled up to a position of 4.2 mm on the scale of the syringe, so that the gas volume was 0.07 mL. The gas layer 53 was fixed to the gasket 3 under the above conditions.

Next, as shown in the photograph of FIG. 6, the syringe 1 was rotated in the upright, depression, horizontal, elevation, and handstand states, and the fixation state of the gas layer 53 was confirmed. From the results shown in FIG. 6, it was confirmed that the gas layer 53 did not separate from the surface of the gasket 3 under the above conditions, and stable fixation could be maintained.

As the gas 53 used in this embodiment, air, nitrogen, or the like can be exemplified, but from the viewpoint of higher safety, the gas enclosed in the vial is used as the gas 53 that does not affect the contacting vaccine drug solution. is more desirable.

As a method for manufacturing the syringe 1 using the gas 53 as the deformable member of the present embodiment, it is possible to manufacture it with an existing production facility of the vacuum capping method. Specifically, as shown in FIG. 7, first, the plunger 4 is pulled out from the syringe 1, and with the gasket 3 taken out, the barrel tip 21 is turned downward and sealed with a stopper 71, and the opening of the outer barrel 2 is closed. 22, the chemical liquid 8 and the gas 53 (nitrogen gas) are injected into the outer cylinder 2 (FIG. 7(A)). Next, the gas 53 in the outer cylinder 2 is decompressed by holding the gasket 3 with a retainer 72 attached with a plugging rod 73 (FIG. 7B), and the gasket 3 is pushed in with the plugging rod 73 in this state. (FIG. 7(C)). When the gasket 3 has been pushed in until the volume of the gas 53 reaches a predetermined amount, the plugging rod 73 is removed, the pusher 4 is attached to the gasket 3, and the cylinder tip 21 is directed downward for storage and transportation ( Figure 7D). The syringe 1 of the present invention can be completed through the series of procedures described above.

Also, in this embodiment, the syringe 1 is preferably a prefilled syringe. A prefilled syringe is not a syringe used by sucking up the drug solution 8 from an ampoule or a vial into the syringe at the time of injection, but a type of syringe filled with a drug in advance. By stably providing the gas layer 53 to the gasket 3 of the prefilled syringe, the syringe can be made more simply and efficiently without wasting the liquid medicine 8 .

Next, procedures up to the completion of injection (intramuscular injection) into a human using the syringe 1 of the present invention into which the drug 8 has been introduced will be described with reference to FIGS. 8 and 9. FIG. The deformation material used in the following description includes both solid or semi-solid deformation material and gas 53 deformation material. First, using the syringe 1 into which the drug 8 is introduced, the injection needle 6 is pierced into the skin 9 so as to reach the muscle 92 through the epidermis 91 (FIG. 8(A)). Next, in this state, the pusher 4 is pressed to inject the drug solution 8 into the muscle 92 (FIGS. 8(B) to (C)). When the pusher 4 is pushed as it is, the deformable material 5 enters the space 23 inside the tube tip 21 (FIG. 9(D)), and then further deforms to enter the internal space 62 of the needle tube 61 . Here, when the pusher 4 is pushed through, the gasket 3 stops at the tube tip 21 side in the outer tube 2, but since the deformable material 5 is provided in advance in a volume in which the conventional chemical liquid 8 remains, the deformable material 5 is needle-shaped. It stays in the space 23 inside the barrel tip and in the space 62 of the needle tube 61 without being ejected from the tip (FIGS. 9(E) and (F)).
According to the syringe 1 of the present invention, the drug solution 8 does not remain in the outer cylinder 2 and the needle tube 61 due to the series of mechanisms described above, and the injection can be completed without waste.

Although the syringe 1 of the present invention has been described above based on the embodiments, the present invention is not limited to the above embodiments, and various modifications are possible without departing from the scope of the invention.

For example, in the above-described embodiment, the volume of the deformable material 5 is set in consideration of the volume inside the needle tube 61. However, if the volume of the space 62 inside the beam tube is negligible, the volume of the deformable material 5 It is also possible to set only the volume of the space 23 in the outer cylinder 2 without including the volume in the needle tube 61 in .

According to the syringe 1 of the present invention having the above configuration, it can be applied to a conventional syringe, and it becomes possible to suppress the residual of the liquid medicine 8 as much as possible when the liquid medicine 8 is injected.

Claims

An outer cylinder provided with a tip having a hole at one end and an opening at the other end, a gasket provided so as to seal and slide inside the outer cylinder, and a plunger connected to the gasket. A syringe comprising
A syringe, wherein a layer of a deformable material that can be freely deformed in shape by external pressure is provided on the surface of the gasket on the side of the barrel tip.
The syringe according to claim 1, wherein the deformable material is a gel-like substance that is difficult to dissolve in the contents of the syringe.
The syringe according to claim 1 or 2, wherein the deformable material is any one of a gel-like substance, a gel-like substance, a clay-like substance, and a gummy-like substance.
3. The volume of the deformable material is equal to the volume of the space existing in the syringe when the plunger of the syringe without the deformable material is pushed all the way to the tip of the syringe. The syringe according to any one of Claims 1 to 3.
The syringe according to claim 4, wherein the volume of the deformable material includes the volume of the space inside the needle tube when the syringe is attached with the needle.
The syringe according to claim 1, wherein the deformable material is gas.
The syringe according to claim 6, wherein the syringe has a capacity of 1 mL or less, and the volume of the gas is 0.07 mL or less.
The syringe according to any one of claims 1 to 7, characterized in that said syringe is a prefilled syringe.