JP2003104419A - Cap for plastic container - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve a problem that a tubular gap caused when a needle or the like pierced in a stopper supported by casings is pulled out of the stopper is not sufficiently closed, resulting in a leakage of a liquid substance sealed inside a plastic container to the outside. SOLUTION: The cap for the plastic container includes the casings 5a and 5b and the stopper 1. A cap including a projection 2 on a side of the container and having an area on an interface of the projection 2 of 25% or more of an area on an upper surface 4 of the stopper is employed as the stopper. In addition, the cap including a plurality of projections on a side of the container on a whole body is employed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cap for a plastic container such as an infusion container and a food container.

[0002]

2. Description of the Related Art Generally, a cap of a plastic container for containing a liquid drug such as an infusion solution or a liquid food product is provided with an elastic stopper and a casing for fixing the stopper. The stopper is capable of sealing the inside of the container. Further, when the tip of a cylindrical needle or the like having a sharp tip typified by an injection needle or the like penetrates the stopper, the drug or the like inside the plastic container flows out through the needle or the like. As possible, the cap is provided so that the injection needle can be pierced in order to mix with the drug or the like inside the plastic container by injecting the drug inside the syringe. For this reason, the plug body is usually made of an elastic material so that a needle or the like can easily penetrate therethrough.

Further, the cap serves to shield the inside of the plastic container from the outside so that the liquid substance contained in the plastic container does not leak outside. For this reason, the casing and the plug constituting the cap have a structure in which the casing supports the plug inside, and the plug and the casing are usually fused or in close contact with each other.

[0004]

When a stopper having a sharp tip is pierced into the stopper supported by the casing, the stopper is pressed in the direction of the casing by the needle to cause volume contraction. However, if the diameter of the inserted needle is large or if the needle is inserted into the plug for a long period of time, the elastic material forming the plug causes stress relaxation and the needle is pulled out from the plug. However, the volume contraction of the stopper may not be restored. If the volumetric shrinkage of the stopper is not sufficiently restored, the tubular void that occurs when the inserted needle or the like is pulled out from the stopper is not sufficiently closed, and the liquid substance enclosed in the plastic container is It leaks to the outside.

[0005]

As a result of earnest studies, the present inventor has found that a plastic container cap having a casing and a plug has a convex portion on the container side.
The present invention has been achieved and the present invention has been achieved by using a plug body in which the area of the boundary surface of the convex portion is 25% or more of the area on the upper surface of the plug body. In a plastic container cap having a casing and a stopper,
It was also found that the above-mentioned problem can be solved by using a stopper having a plurality of convex portions on the container side.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The first invention of the present application is a plastic container cap comprising a casing and a stopper, wherein the stopper has a convex portion on the container side.
The area of the boundary surface of the convex portion is 25% or more of the area of the upper surface of the plug body.

FIG. 1 is a schematic cross-sectional view of a plastic container cap showing an embodiment of the first invention. In FIG. 1, the plug is composed of a plug main part and a convex part, 1 is the plug main part, 2 is the convex part of the plug, 3 is the plug fixing part, and 4 is the upper surface of the plug. Reference numerals 5a and 5b are casings for supporting the main plug body 1. In addition, X shown by a dotted line in FIG. 1 is a virtual boundary surface of the convex portion. The boundary surface is a boundary surface between the main plug portion and the convex portion, that is, a boundary between a portion constrained by the casing and a portion not constrained by the casing.

In the embodiment shown in FIG. 1, the main plug body portion 1 is fixed to the casing at the fixing portion 3 of the plug body, and the convex portion 2 is provided.
Is not fixed to the casing. The said convex part is a part which is not restrained by a casing and a container. When the needle is inserted in this embodiment, the state shown in FIG. 2 is obtained. The main part of the plug body that extends from the upper surface 4 to the inside of the container and reaches the convex part 2 is horizontal (toward the fixed part) because the main part 1 of the plug body is fixed by the fixing part 3.
The volume contraction occurs due to the inability to spread. Due to this volume contraction, the elastic body forming the main part of the plug body causes stress relaxation, and when the needle 7 is pulled out, the shape of the main body of the plug body is not sufficiently restored and the needle body is not restored. The withdrawal marks may not be fully covered. However, since the convex portion in the state of FIG. 2 is not fixed to the casing and deforms while expanding in the horizontal direction (direction of the fixed portion), volume contraction does not occur, so that elasticity of the needle before insertion is maintained. Then
Can sufficiently close the trace of needle withdrawal.

FIG. 3 is a schematic sectional view of a plastic container cap showing another embodiment of the first invention. On the upper surface 4 of the main plug body portion 1, a recess 6 is provided near the outer periphery 41 of the upper surface. In this embodiment, since the recess 6 is not provided in the center of the upper surface but is provided near the outer peripheral portion 41, when the needle is withdrawn from the recess and then the needle is pulled out, as shown in FIG. As shown, a curved drawing mark 8 is formed from the concave portion to the end of the convex portion. As shown in FIG. 5, when the tip of the needle 7 penetrates the position close to the side surface 10 of the convex portion 2, the amount of the elastic body that receives the pressure from the needle tip at the time of insertion is the side surface of the convex portion. Since the vicinity is different from the vicinity of the center of the convex portion, the convex portion easily extends near the side surface of the convex portion where the amount of the elastic body that receives the pressure is small. Therefore, the withdrawal mark 8 in FIG.
It is curved near the convex portion, and is a withdrawal mark having a longer distance by the curved amount as compared with the withdrawal trace of the needle when the needle is inserted near the center of the convex portion. The withdrawal mark 8 in FIG. 4 is a withdrawal mark with a long distance, and therefore, the deformation of the elastic body due to the needle insertion is restored to sufficiently close the withdrawal mark, which is advantageous compared with the withdrawal mark with a short distance. . In addition, the withdrawal trace in which the tip portion is curved and draws an arc has a portion in which the width is formed in the vertical direction, and this portion is easily blocked by the restoring force of the elastic body against the pressure when the needle is inserted, It has the property of being easier to seal than a linear drawing trace. Further, since the convex portion does not cause volume contraction due to the insertion of a needle or the like, stress relaxation does not occur, and since the convex portion retains a sufficient ability to restore deformation, it is possible to sufficiently close the extraction trace. . That is, it is preferable to provide the upper surface 4 of the plug body main portion 1 with a recess in order to prevent leakage of the liquid substance inside the container sealed with the cap including the plug body.

It is sufficient that at least one recess is provided in the vicinity of the outer periphery of the upper surface of the main portion of the plug body, and it is not particularly limited, but it is preferable that two to five recesses be provided. preferable. The shape of the concave portion is not particularly limited, but the space portion may be conical or cylindrical, but it is easy to see as a mark at the time of needle stick, and is effective for guiding at the time of needle stick. It is preferably conical so that there is. The depth of the recess is preferably 0.3 to 2 mm, and when it is less than 0.5 mm it is not noticeable because it is inconspicuous, and when it is more than 1.5 mm, the thickness of the plug body This is because the liquid leakage is likely to be affected due to the decrease in the amount. The concave portion is for facilitating needle penetration, and since the tip of the needle pierced from the concave portion penetrates the convex portion, the position where the concave portion is provided is the center of the concave portion. It is preferable that it is vertically above the position where the projection is provided in the main part of the plug body. Also,
Since the length of the path through which the needle is inserted into the plug increases because the plug is provided with a convex portion, in order to facilitate the insertion of the needle, the same degree of insertion as when no protrusion is provided You may provide the recessed part of the depth which becomes a path length.

The plug body of the first invention may be made of any material as long as it has sufficient elasticity to close the trace of needle withdrawal.
Although not particularly limited, a resin containing a thermoplastic elastomer can be used. Examples of the thermoplastic elastomer include a hydrogenation type polyethylene elastomer, a polyvinyl chloride elastomer, a polyolefin elastomer, a polyurethane elastomer, a polyester elastomer, a polyamide elastomer, and the like, which can be sterilized. A polystyrene-based elastomer is preferable because heat resistance to water vapor is required to some extent. The resin containing the thermoplastic elastomer may be a mixture of a thermoplastic elastomer and rubber, in addition to the case of only the thermoplastic elastomer. The rubber is not particularly limited, but may be silicone rubber. It is preferable to use since it has good physical properties such as durability.

The protrusion provided on the plug according to the first aspect of the invention is not limited to the embodiment of FIG. 1 and the embodiment of FIG.
The shape is not particularly limited, and may be in the shape of a pyramid or a pillar, but is preferably a pillar, and may be a cylinder or a quadrangular pillar, but is more preferably a cylinder. Since the convex portion hardly causes volume contraction due to the pressure when the needle is inserted, it is preferable that the wall surface of the convex portion does not contact the inner wall surface of the casing or the plastic container.

The thickness of the convex portion is not particularly limited, but is preferably 0.3 to 6 mm. 0.3
If it is less than mm, it is not preferable because it cannot obtain the effect of blocking the needle after withdrawal, and if it is more than 6 mm, the effect of already closing the needle after withdrawal is sufficient, and the effect is improved even if the thickness is increased. It is not preferable because the material is lost without doing so.

In the convex portion of the plug according to the first invention,
Although the bottom portion 15 of the convex portion in FIG. 1 has a substantially flat shape, a plurality of small convex portions or small concave portions may be provided on the boundary surface of the convex portions. The shape of the small convex portion is not particularly limited, but it is preferable that the curved surface portion or the inclined portion occupies more than half of the surface area of the convex portion such as a semicircular shape or a conical shape. This is because, if the curved surface portion or the inclined portion is penetrated when the needle is inserted, a withdrawal trace in which the tip draws an arc, such as the withdrawal trace 8 of the needle in FIG. 3, is obtained when the needle is withdrawn. The shape of the small concave portion is not particularly limited, but for the same reason as the small convex portion, a curved surface portion or an inclined portion such that the space portion of the concave portion has a semicircular shape or a conical shape. Occupies more than half of the surface area of the convex portion. In addition, the side surface of the convex portion can obtain a drawing trace in which the tip draws an arc similarly to the above reason,
It is preferable to provide a small convex portion or a small concave portion.

The area of the boundary surface of the convex portion is preferably 25% or more of the area on the upper surface of the plug body, and may be 100% depending on the shape of the container. The area of the boundary surface of the convex portion is at least 2 with respect to the area of the upper surface of the plug main portion.
If it is 5% or more, if the convex portion is provided near the center of the mouth of the plastic container in which the stopper is sealed, the needle is accurately inserted into the center of the upper surface of the stopper. It is not necessary and is preferable because the work of inserting the needle can be prepared.

The convex portion may be formed substantially integrally with the entire body, and may be integrally molded with a mold so that the convex portion does not fall out of the plug body when a needle is inserted. It may be fused, welded or adhered.

The plastic container cap of the first invention is a plastic container cap provided with a casing and a plug body. If necessary, as shown in FIG. 6, a sealing body is placed on the plug body. It is preferable to provide a pull-top type cap. By providing the sealing body, the plug body can be protected, deterioration of the plug body can be prevented, and it becomes easy to maintain the ability to restore deformation to sufficiently close the withdrawal trace of the needle or the like. Is.

The second invention of the present application is a plastic container cap provided with a casing and a plug body, wherein the plug body is also a cap provided with a plurality of convex portions on the container side.

FIG. 7 is a schematic cross-sectional view of a plastic container cap showing an embodiment of the second invention, and is a view after the inserted needle is removed. In FIG. 7, 1 is a plug, 2
Reference numerals 1, 22, 23, 24, and 25 denote convex portions of the stopper body, 3 denotes a stopper body fixing portion, and 4 denotes an upper surface of the stopper body. 5a and 5b are stoppers 1
Is a casing for supporting.

In the embodiment of FIG. 7, the stopper 1 is fixed to the casing at the fixing portion 3 of the stopper, and the projection 2
1, 22, 23, 24 and 25 are not fixed to the casing. The said convex part is a part which is not restrained by a casing and a container. The portion of the plug body that extends from the upper surface 4 to the inside of the container and reaches the convex portion 2 is the plug body 1.
1 is fixed in the fixing portion 3, it cannot spread in the horizontal direction (fixing portion direction) as in the embodiment of FIG. However, since the convex portion of the embodiment of FIG. 7 is not fixed to the casing and can be easily deformed, volume contraction does not occur, so that the elasticity before the needle is inserted is retained and the needle is pulled out. The traces can be fully blocked.

Further, in the embodiment of FIG. 7, in the convex portion 23 near the center of the stopper, the needle mark 8 is shown when the needle inserted into the stopper penetrates the side surface 14 of the convex portion. . When the needle inserted into the stopper penetrates the side surface 14 of the protrusion,
The difference in elongation as shown in Fig. 2 occurs in the part near the insertion needle,
Similar to the needle trace 8 shown in FIG. 4, a needle trace 8 having an arc near the tip is obtained. In the embodiment of FIG. 7, since there are a plurality of protrusions, it is highly likely that the needle penetrates the inclined portion of the protrusion when the needle is inserted into the plug body. It is possible to easily obtain a needle trace similar to that obtained when the needle is inserted into the. That is, in the embodiment of FIG. 7 which is the second invention, as compared with the plug body of the embodiment of FIG. 1, it is easier to obtain a needle trace that draws an arc near the tip after the needle that has been inserted is removed, This makes it easier to seal the enclosed liquid material.

In the second invention, valleys are formed between the convex portions 21 and 22, 22 and 23, 23 and 24, and 24 and 25 in FIG. The valley formed between the one convex portion and the adjacent convex portion is not particularly limited,
In FIG. 7, the width Z of the plug body in the vicinity of the valley is set to be wider than the width Y of the plug body in the vicinity of the plug body fixing portion 3 by being formed shallowly, but it is formed to be deep to form the plug body. The width Z of the plug near the valley may be narrower than the width Y of the plug near the fixed portion 3. When the width Z is formed to be equal to or narrower than the width Y, the enclosed contents are likely to leak when the needle inserted into the plug penetrates the trough, and therefore a recess may be provided on the upper surface. preferable.

In the second invention, FIG. 3 of the first invention is used.
The upper surface may be provided with a recess as in the above embodiment. Since the recessed portion guides the insertion of the needle, it is preferable that the center of the recessed portion be located at the apex of the protruding portion or vertically above the inclined portion.

In the second invention, the number of the convex portions provided on the plug body may be plural and is not particularly limited as long as it is two or more. The shape of the convex portion is not particularly limited, and may be a substantially conical shape or a columnar shape, and may be a quadrangular pyramid, a triangular pyramid, or a random uneven shape, but a substantially conical shape. Alternatively, it is preferable that the projections and projections are randomly formed because the projections are easily formed. Further, as shown in FIG. 7, since the valley portion is formed shallowly,
Each convex portion near the plug main portion may be integrally formed to form the convex trunk portion 16, and the convex portion may be separated from the tip of the convex trunk portion to form a plurality of convex portions. The shape may be substantially the same as the shape in which a plurality of small projections are provided on the bottom surface of the projection. It is preferable to provide a small convex portion or a small concave portion in the inclined portion 17 on the outer side surface of the convex trunk so that it is easy to obtain a trace of withdrawal in which the tip forms an arc.

The material of the plug in the second invention is not particularly limited, but a resin containing a thermoplastic elastomer can be used as in the first invention, and the thermoplastic elastomer is hydrogenated. Examples include polyethylene elastomers including types, polyvinyl chloride elastomers, polyolefin elastomers, polyurethane elastomers, polyester elastomers, polyamide elastomers, etc., but they have heat resistance to water vapor to the extent that they can be sterilized. It is preferably a polystyrene elastomer because it is necessary.
The resin containing the thermoplastic elastomer may be a mixture of a thermoplastic elastomer and rubber, in addition to the case of only the thermoplastic elastomer. The rubber is not particularly limited, but may be silicone rubber. It is preferable to use since it has good physical properties such as durability.

The thickness of the convex portion in the second invention is not particularly limited, but is 0.3 to 0.3 as in the first invention.
It is preferably 6 mm. If it is less than 0.3 mm, it is not preferable because it cannot obtain the effect of blocking the needle after withdrawal, and if it is more than 6 mm, the effect of already closing the needle after withdrawal is sufficient and the effect is obtained even if the thickness is increased. Is not improved and the material is lost, which is not preferable.

Also in the second invention, as in the first invention, it is preferable to provide a sealing body on the plug as needed to form a pull-top type cap.

[0028]

According to the first aspect of the present invention, in a plastic container cap having a casing and a stopper, the stopper has a convex portion on the container side, and a boundary surface of the convex portion is formed. The area of the cap is 25% or more of the area on the upper surface of the stopper, and the second invention is a plastic container cap comprising a casing and a stopper, wherein the stopper has a plurality of protrusions on the container side. It is a cap provided with a part.
According to the first invention and the second invention, even if the needle is left in a state of being pierced for a long period of time, or if a needle having a large diameter is used, the needle withdrawal marks generated when the needle is pulled out Can be fully blocked.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view of a plastic container cap showing an embodiment of the first invention of the present application.

FIG. 2 is a schematic cross-sectional view showing a state where a needle is inserted into the plastic container cap of the embodiment of FIG.

FIG. 3 is a schematic cross-sectional view of a plastic container cap according to another embodiment of the first invention of the present application.

FIG. 4 is a schematic cross-sectional view showing a state in which a needle inserted into the plastic container cap of the embodiment shown in FIG. 3 is pulled out.

5 is a schematic cross-sectional view showing a state in which a needle is inserted into the plastic container cap of the embodiment of FIG.

FIG. 6 is a schematic cross-sectional view of a pull-top cap including a sealing body in the plastic container cap of the embodiment of FIG.

FIG. 7 is a schematic cross-sectional view of a plastic container cap showing another embodiment of the second invention of the present application.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Plug 2 Convex part 21, 22, 23, 24, 25 Convex part 3 Plug body fixing part 4 Upper surface 41 Vicinity of outer periphery of upper surface 5a, 5b Casing 6 Recess 7 Needle 8 Needle withdrawal mark 9 Sealing body 10 Side 11 Pull top piece 12 Sealing body 13 Valley 14 Convex curved surface 15 Convex bottom 16 Convex trunk 17 Slope X Virtually convex boundary surface Y Width of plug Z near the plug fixing part Plug near the valley Width of

Claims (5)

[Claims] 1. A plastic container cap having a casing and a plug body, wherein the plug body has a convex portion on the container side, and the area of the boundary surface of the convex portion is the upper surface of the plug body. A cap that is 25% or more of the area. 2. The cap according to claim 1, wherein the convex portion of the plug body is at least substantially formed integrally with the main body of the plug body. 3. The cap according to claim 1 or 2, wherein a concave portion is provided on an upper surface of the stopper body near an outer periphery of the upper surface. 4. The cap according to claim 1, wherein the center of the recess is vertically above the position where the protrusion is provided in the plug body. 5. A cap for a plastic container including a casing and a stopper, wherein the stopper has a convex portion on the container side, and the cap has a plurality of convex portions.