JP4277146B2

JP4277146B2 - cap

Info

Publication number: JP4277146B2
Application number: JP25129999A
Authority: JP
Inventors: 輝昭林田; 光治林田
Original assignee: Mikasa Sangyo Co Ltd
Current assignee: Mikasa Sangyo Co Ltd
Priority date: 1999-09-06
Filing date: 1999-09-06
Publication date: 2009-06-10
Anticipated expiration: 2019-09-06
Also published as: JP2001072099A

Description

【０００１】
【発明の属する技術分野】
この発明は、ガラス製等の液体容器の口部に嵌着される中栓のような合成樹脂製のキャップに関するものである。
【０００２】
【従来技術】
図５は、例えば実開昭６４−２９１５６号公報で開示された合成樹脂製の蓋に関するものである。
図において、３は容器１より突出する口部２を遮蔽する遮蔽部で栓体形状を有する。７は嵌合部で頂壁４によって連結される外筒５および内筒６からなっている。１１はカバー、９は頂壁に形成された通孔である。
【０００３】
このような合成樹脂製の蓋を、容器内容物を高温で充填し、嵌合部７を容器１より突出する口部２に打栓装着するときは、嵌合部７と口部２との間に残存する空気は通孔９を経て上方に流出するため、キャップ８は口部２に深く装着され、抜ける恐れがない。
【０００４】
また、上記の例では通孔９を頂壁４に備えているが、これに代えて図６に示す如く外筒５の内周にエア抜き溝を形成したものもある。つまり、上記口部２のくびれ凹部２ａに嵌合するリング状の突状５ａを外筒５の内周に形成し、この突条５ａに横断面Ｕ字状のエア抜き溝１３を多数設けたものである。
【０００５】
このような合成樹脂製の蓋を容器内容物を高温で充填し、嵌合部７を容器１より突出する口部２に打栓装着するときは、嵌合部７と口部２との間に残存する空気はエア抜き溝１３を経て下方に流出することになるからエアの残存による装着不良は阻止される
【０００６】
【発明が解決しようとする課題】
しかしながら、中栓のような合成樹脂製のキャップをガラス製等の液体容器１の口部２に打栓装着するにあたり、前者の例では、容器内容物を高温で充填するので、充填後常温に冷却されたときに、容器内が減圧となるため、外気が通孔９を通じて容器内に侵入し易くなり、容器内容物が食品の場合腐敗などを起す恐れがある。また、後者の例では、横断面Ｕ字状のエア抜き溝１３では嵌合の際拡がりにくく、復元力も充分でない。従って嵌合力が低下し、外れ易くなるという問題がある。
【０００７】
本発明はこれらの問題点を解決するためになされたもので、中栓のような合成樹脂製のキャップをガラス製等の液体容器の口部に打栓装着するにあたり、嵌合部７と口部２との間に介在するエアを排出し、外気との遮断を一層強化し、嵌合力の低下を最小限にとどめることができるキャップを得ることを目的とする。
【０００８】
【課題を解決するための手段】
本発明は、上記目的を達成するためになされたもので、請求項１記載のキャップは、容器１より突出する口部２を遮蔽する開口可能な遮蔽部３と、頂壁４によって連結される外５筒および内筒６からなる嵌合部７とを備えた合成樹脂製のキャップ８において、上記頂壁４に少なくとも一つの通孔９を備え、容器１の口部２に上記嵌合部７を打栓装着する際、該嵌合部７と口部２との間に残存する空気により押し開かれ、該空気を前記通孔９より流出させ、上記嵌合部７の嵌合終了時に嵌合した容器１の口部２の上端面に密接して外気の容器内への侵入を阻止し、通孔９を内側よりシール状態とする可撓性舌片１０を上記嵌合部７と一体に形成したものである。
【０００９】
また、この発明に係る請求項２記載のキャップは、容器１より突出する口部２を遮蔽する開口可能な遮蔽部３と、頂壁４によって連結される外筒５および内筒６からなる嵌合部７とを備えた合成樹脂製のキャップ８において、上記頂壁４に少なくとも一つの通孔９を備え、容器１の口部２に上記嵌合部７を打栓装着する際、該嵌合部７と口部２との間に残存する空気により押し開かれ、該空気を前記通孔９より上方に流出させ、上記嵌合部７の嵌合終了時に容器１の口部２の上端面に密接して外気の容器内へ侵入を阻止し、通孔９を内側からシール状態とする可撓性舌片１０を上記嵌合部に一体に形成し、また、上記口部２のくびれ凹部２ａに圧接嵌合するリング状の突条５ａを外筒５の内周に形成し、横断面鋭角Ｖ字形の通気用スリット溝１３を上記突条５ａの中心軸の対称位置に複数箇所形成したものである。
【００１０】
【発明の実施の形態】
請求項１に関する発明の実施の形態を実施例に基づき図面を参照して説明する。図１，図２は一部切断正面図である。図において、１は容器、２は口部、３は遮蔽部で、薄肉状のスコア３ａとプルタブ１４を有し、スコアに沿って切り裂き引き抜き可能となっている。５は口部２に嵌着される外筒、４は口部２の上側曲面に被嵌される頂壁、６は内筒、１６は環状の注出し口である。上記の外筒５、頂壁４、内筒６、注出し口１６、遮蔽部３によって軟質ポリエチレンからなる中栓２０が形成される。
【００１１】
３０はポリプロピレンからなる嵌合リングで、上記中栓２０に嵌着されるものである。嵌合リング３０の上部内側には水平リング３１が突設され、上記中栓２０の肩部と当接されるものである。嵌合リング３０にはヒンジ３２を介して外蓋３３が一体化され、この外蓋３３によって嵌合リング３０の開口部を封止することができる。外蓋３３には内リング３４と外リング３５とが突設され、外蓋を閉じたとき内リング３４と外リング３５との間に注出し口部１６が当接するので、転倒しても液漏れすることがない。
【００１２】
頂壁４には少なくとも一つの通孔９が備えられ、この通孔９の口部２側には逆様の椀状凹部９ａが形成され、この椀状凹部９ａに可撓性舌片１０が接続部１０ａを介して射出成形時に一体に形成され、これにより、上記嵌合部７の嵌合終了時に可撓性舌片１０は容器１の口部２の上端面に密接し、通孔９を内側よりシール状態とすることができる。図１は接続部１０ａを内側に設定した実施例図、図２は接続部１０ａを外側に設定した実施例である。
【００１３】
次に請求項１に係る本発明の作用について説明する。
予め中栓２０に嵌合部７を嵌着させ、これを嵌着打栓する際、嵌合部７の内部に残存する空気は、接続部１０ a を介して一体に形成され可撓性舌片１０の一端を押圧し、椀状凹部９ａより通孔９を経て流出し、嵌合部７の嵌合終了後、通孔９は内側より可撓性舌片１０によってシール状態とされることによって、嵌合リング３０と口部２とはよく密着し、キャップの抜けが防止される。容器内用物を高温で充填する場合は、充填後常温に冷却されたときに容器内が減圧となるため外気が侵入しようとするが、容器１の口部２の上端面に密接した可撓性舌片１０によってシール状態とされるため、容器内に細菌などが侵入する恐れはない。
【００１４】
次に、請求項２に関する発明の実施の形態を図１〜図４について説明する。
容器１より突出する口部２を遮蔽する開口可能な遮蔽部３と、頂壁４によって連結される外５筒および内筒６からなる嵌合部７とを備えた合成樹脂製のキャップ８において、上記頂壁４に少なくとも一つの通孔９を備え、容器１の口部２に上記嵌合部７を打栓装着する際、該嵌合部７と口部２との間に残存する空気により押し開かれ、該空気を前記通孔９より上方に流出させ、上記嵌合部７の嵌合終了時に容器１の口部２の上端面に密接し、通孔９を内側からシール状態とする可撓性舌片１０を上記嵌合部に一体に形成に形成し、また、上記容器１の口部２のくびれ凹部２ａに圧接嵌合するリング状の突条５ａが外筒５の内周に形成され、横断面鋭角Ｖ字形の通気用スリット溝１３を上記突条５ａの中心軸の対称位置に複数箇所形成したものである。
【００１５】
次に請求項２に関する本発明の作用について説明する。
頂壁４によって連結される外筒５および内筒６からなる嵌合部７を高温液体を充填した容器１より突出する口部２に打栓装着によって嵌着させる際、嵌合部７の内部に残存する空気は椀状凹部９ａより通孔９を経て流出した後、通孔９は内側より可撓性舌片１０によってシール状態とされることによって、嵌合リング３０と口部２とはよく密着し、キャップの抜けが防止される。容器内用物を高温で充填する場合は、充填後常温に冷却されたときに容器内が減圧となるため外気が侵入しようとするが、可撓性舌片１０によってシール状態とされるため、容器内に細菌などが侵入する恐れはない。
また、リング状の突条５ａの通気用スリット溝１３は口部２の径大部を乗越える時に一旦拡がるので、頂壁４と口部２との間の空気は確実に通気用スリット溝１３を通って排出される。
一方、口部２の径大部を乗越えたリング状の突条５ａは口部２のくびれ凹部２ａに嵌合するので、装着終了後は、弾性的復元能力が大きい横断面鋭角Ｖ字形の通気用スリット溝１３は元の形状に復原し、このため嵌合力が低下することはない。
また、図４に示すように、通気用スリット溝１３は中心軸の対称位置に形成されているので、嵌合保持の動作バランスがよく行われる。
なお、通気用スリット溝１３は通常キャップの成形時に形成されるが、キャップの成形後、リング状の突条の先端部を垂直方向に切削して形成することもできる。
【００１６】
前記した請求項１に関する本発明と請求項２に関する本発明を同時に施してもよく、別々に実施してもよい。
【００１７】
【発明の効果】
本発明は、以上説明したように構成されているので、以下に記載されるような効果を奏する。
【００１８】
本発明の請求項１記載のキャップは、嵌合部７の頂壁４に少なくとも一つの通孔９を備え、この通孔９を上記嵌合部７の嵌合終了時に内側よりシール状態とする可撓性舌片１０を上記嵌合部７と一体に形成したことにより、嵌合部７と容器１より突出する口部２に打栓装着するときは、嵌合部７と口部２との間に残存する空気は通孔９を経て上方に流出するため、キャップ８は口部に深く装着され、抜ける恐れがない。また、容器内容物の高温充填後、冷却されたときに容器内が減圧となるため外気が侵入しようとするが、可撓性舌片１０によってシール状態とされるため。容器内に細菌などが侵入する恐れがない。
【００１９】
本発明の請求項２記載のキャップは、請求項１におけるキャップにおいて、さらに、容器１の口部２のくびれ部凹部２ａに圧接嵌合するリング状の突条５ａを外筒５の内周に形成し、横断面鋭角Ｖ字形の通気用スリット溝１３を上記突条５ａの中心軸の対称位置に複数個所形成したことにより、嵌合部７と口部２との間に残存する空気は通気用スリット溝１３を経て下方に流出することになるからエアの残存による装着不良は阻止され、しかも、一旦拡がった通気用スリット溝１３は弾性的に元の形状に容易に復原し、このため嵌合力が低下することもない。
また、嵌合保持の動作がバランスよく行われる。
【図面の簡単な説明】
【図１】請求項１の発明に関するキャップの一部切断正面図である。
【図２】請求項１の発明に関するキャップの一部切断正面図で、可撓性舌片の取付け位置変化させたものである。
【図３】請求項２の発明に関するキャップの一部切断正面図である。
【図４】請求項２の発明に関するキャップの要部の平面図である
【図５】実開昭６４−２９１５６号公報で開示された公知のキャップの断面図である。
【図６】公知のキャップの要部の断面図である。
【符号の説明】
１容器
２口部
２ａくびれ部
３遮蔽部
４頂壁
５外筒
５ａ突条
６内筒
７嵌合部
８キャップ
９通孔
９ａ椀状凹部
１０可撓性舌片
１３通気用スリット溝
１４プルタブ
１６注出し口
２０中栓
３０嵌合リング
３１水平リング
３２ヒンジ
３３外蓋
３４内リング
３５外リング[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a synthetic resin cap such as an inner plug fitted to the mouth of a liquid container made of glass or the like.
[0002]
[Prior art]
FIG. 5 relates to a synthetic resin lid disclosed in, for example, Japanese Utility Model Publication No. 64-29156.
In the figure, 3 is a shielding part that shields the mouth part 2 protruding from the container 1 and has a stopper shape. Reference numeral 7 denotes an outer cylinder 5 and an inner cylinder 6 which are connected by a top wall 4 at a fitting portion. 11 is a cover, 9 is a through-hole formed in the top wall.
[0003]
When such a synthetic resin lid is filled with the contents of the container at a high temperature and the fitting part 7 is plugged into the mouth part 2 protruding from the container 1, the fitting part 7 and the mouth part 2 Since the air remaining therebetween flows upward through the through-hole 9, the cap 8 is deeply attached to the mouth portion 2 and there is no fear of coming off.
[0004]
Further, in the above example, the through hole 9 is provided in the top wall 4, but instead, there is a case in which an air vent groove is formed on the inner periphery of the outer cylinder 5 as shown in FIG. 6. That is, a ring-shaped protrusion 5a that fits into the constricted recess 2a of the mouth 2 is formed on the inner periphery of the outer cylinder 5, and a plurality of air vent grooves 13 having a U-shaped cross section are provided in the protrusion 5a. Is.
[0005]
When such a synthetic resin lid is filled with the contents of the container at a high temperature and the fitting part 7 is plugged into the mouth part 2 protruding from the container 1, the gap between the fitting part 7 and the mouth part 2 is set. Since the air remaining in the air flows downward through the air vent groove 13, mounting failure due to the remaining air is prevented.
[Problems to be solved by the invention]
However, when a cap made of synthetic resin such as an inner plug is plugged into the mouth portion 2 of the liquid container 1 made of glass or the like, in the former example, the container contents are filled at a high temperature. Since the inside of the container is depressurized when cooled, the outside air is liable to enter the container through the through-hole 9, and there is a possibility that the container contents may be spoiled. In the latter example, the air vent groove 13 having a U-shaped cross section is difficult to expand during fitting, and the restoring force is not sufficient. Therefore, there exists a problem that fitting force falls and it becomes easy to remove | deviate.
[0007]
The present invention has been made in order to solve these problems. When a cap made of a synthetic resin such as an inner stopper is plugged into the mouth of a liquid container such as glass, the fitting portion 7 and the mouth are provided. An object of the present invention is to obtain a cap that discharges air intervening between the portion 2 and further enhances the shut-off from the outside air, and can minimize a decrease in fitting force.
[0008]
[Means for Solving the Problems]
The present invention has been made to achieve the above object, and the cap according to claim 1 is connected to the openable shielding portion 3 for shielding the mouth portion 2 protruding from the container 1 by the top wall 4. In the synthetic resin cap 8 provided with the outer cylinder 5 and the fitting part 7 composed of the inner cylinder 6, the top wall 4 is provided with at least one through hole 9, and the fitting part is provided in the mouth part 2 of the container 1. When the stopper 7 is mounted, the air remaining between the fitting portion 7 and the mouth portion 2 is pushed open, and the air flows out from the through hole 9. A flexible tongue piece 10 that is in close contact with the upper end surface of the mouth portion 2 of the fitted container 1 to prevent the entry of outside air into the container and seals the through hole 9 from the inside is provided with the fitting portion 7. It is formed integrally.
[0009]
According to a second aspect of the present invention, the cap includes an openable shielding portion 3 that shields the mouth portion 2 protruding from the container 1, and an outer cylinder 5 and an inner cylinder 6 connected by the top wall 4. In the synthetic resin cap 8 provided with the joint portion 7 , the top wall 4 is provided with at least one through hole 9, and when the fitting portion 7 is plugged into the mouth portion 2 of the container 1, the fitting is performed. Pushed open by the air remaining between the joint portion 7 and the mouth portion 2, the air flows out from the through hole 9, and when the fitting portion 7 is finished fitting, A flexible tongue piece 10 is formed in the fitting portion so as to prevent the entry of outside air into the container in close contact with the end face, and the through hole 9 is sealed from the inside, and the constriction of the mouth portion 2 is formed. forms a ring-like lip 5a for press fitting into the recess 2a in the inner periphery of the outer cylinder 5, the slit grooves for ventilation cross section an acute angle V-shaped 3 is obtained by forming a plurality of locations on the symmetrical position of the center axis of the protrusion 5a.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
An embodiment of the invention relating to claim 1 will be described based on examples with reference to the drawings. 1 and 2 are partially cut front views. In the figure, 1 is a container, 2 is a mouth portion, and 3 is a shielding portion, which has a thin score 3a and a pull tab 14, and can be cut and pulled along the score. 5 is an outer cylinder fitted to the mouth part 2, 4 is a top wall fitted to the upper curved surface of the mouth part 2, 6 is an inner cylinder, and 16 is an annular pouring port. An inner plug 20 made of soft polyethylene is formed by the outer cylinder 5, the top wall 4, the inner cylinder 6, the pouring port 16, and the shielding part 3.
[0011]
Reference numeral 30 denotes a fitting ring made of polypropylene, which is fitted to the inner plug 20. A horizontal ring 31 protrudes from the inside of the upper portion of the fitting ring 30 and comes into contact with the shoulder portion of the inner plug 20. An outer lid 33 is integrated with the fitting ring 30 via a hinge 32, and the opening of the fitting ring 30 can be sealed by the outer lid 33. An inner ring 34 and an outer ring 35 project from the outer lid 33. When the outer lid is closed, the spout 16 contacts between the inner ring 34 and the outer ring 35. There is no leakage.
[0012]
The top wall 4 is provided with at least one through hole 9, and a reverse hook-shaped recess 9 a is formed on the mouth 2 side of the through-hole 9, and a flexible tongue piece 10 is formed in the hook-shaped recess 9 a. It is integrally formed at the time of injection molding through the connecting portion 10a, whereby the flexible tongue piece 10 is brought into close contact with the upper end surface of the mouth portion 2 of the container 1 at the end of the fitting of the fitting portion 7, and the through hole 9 Can be sealed from the inside. FIG. 1 shows an embodiment in which the connecting portion 10a is set inside, and FIG. 2 shows an embodiment in which the connecting portion 10a is set outside.
[0013]
Next, the operation of the present invention according to claim 1 will be described.
To fitting the fitting portion 7 to the inner plug 20 in advance, when fitted capping this, air remaining in the interior of the fitting portion 7, via the connecting portion 10 a is formed integrally with a flexible tongue One end of the piece 10 is pressed and flows out from the bowl-shaped recess 9a through the through hole 9. After the fitting of the fitting portion 7 is finished, the through hole 9 is sealed by the flexible tongue piece 10 from the inside. Therefore, the fitting ring 30 and the mouth portion 2 are in close contact with each other, and the cap is prevented from coming off. When filling the container internals at a high temperature, the inside of the container is depressurized when it is cooled to room temperature after filling, so that outside air tends to enter, but the container 1 is in close contact with the upper end surface of the mouth 2. Since it is sealed by the sex tongue piece 10, there is no possibility that bacteria or the like will enter the container.
[0014]
Next, an embodiment of the invention relating to claim 2 will be described with reference to FIGS.
In a cap 8 made of synthetic resin , including an openable shielding portion 3 that shields the mouth portion 2 protruding from the container 1, and a fitting portion 7 including an outer cylinder 5 and an inner cylinder 6 connected by the top wall 4 . The top wall 4 is provided with at least one through hole 9, and when the fitting part 7 is plugged into the mouth part 2 of the container 1, the air remaining between the fitting part 7 and the mouth part 2 The air is caused to flow upward from the through-hole 9 and close to the upper end surface of the mouth portion 2 of the container 1 when the fitting portion 7 is fitted, and the through-hole 9 is sealed from the inside. A flexible tongue piece 10 is formed integrally with the fitting portion, and a ring-shaped ridge 5a that press-fits into the constricted recess 2a of the mouth portion 2 of the container 1 is provided inside the outer cylinder 5. A plurality of ventilation slit grooves 13 formed on the circumference and having an acute V-shaped cross section are formed at symmetrical positions with respect to the central axis of the protrusion 5a. A.
[0015]
Next, the operation of the present invention relating to claim 2 will be described.
When fitting the fitting part 7 composed of the outer cylinder 5 and the inner cylinder 6 connected by the top wall 4 into the mouth part 2 protruding from the container 1 filled with high-temperature liquid by plugging , the inside of the fitting part 7 After the air remaining in the gas flows out through the through-hole 9 from the bowl-shaped recess 9a, the through-hole 9 is sealed from the inside by the flexible tongue piece 10, whereby the fitting ring 30 and the mouth portion 2 are separated from each other. Adheres well and prevents cap removal. When filling the container internals at a high temperature, the inside of the container is depressurized when cooled to room temperature after filling, so that outside air tends to enter, but the flexible tongue 10 is in a sealed state, There is no risk of bacteria entering the container.
Further, since the ventilation slit groove 13 of the ring-shaped protrusion 5a temporarily expands when getting over the large diameter portion of the mouth portion 2, the air between the top wall 4 and the mouth portion 2 is surely vented. Discharged through.
On the other hand, the ring-shaped ridge 5a that has passed over the large-diameter portion of the mouth portion 2 is fitted into the constricted recess portion 2a of the mouth portion 2. Therefore, after the attachment is completed, the cross-section acute angle V-shaped air passage having a large elastic restoring ability is provided. The slit groove 13 is restored to its original shape, so that the fitting force is not reduced.
Further, as shown in FIG. 4, since the ventilation slit groove 13 is formed at a symmetrical position with respect to the central axis, an operation balance of fitting and holding is well performed.
In addition, although the slit groove 13 for ventilation | gas_flowing is normally formed at the time of shaping | molding of a cap, after shaping | molding a cap, the front-end | tip part of a ring-shaped protrusion can also be cut and formed in a perpendicular direction.
[0016]
The present invention related to claim 1 and the present invention related to claim 2 may be performed simultaneously or separately.
[0017]
【The invention's effect】
Since the present invention is configured as described above, the following effects can be obtained.
[0018]
The cap according to claim 1 of the present invention is provided with at least one through hole 9 in the top wall 4 of the fitting portion 7, and this through hole 9 is sealed from the inside when the fitting portion 7 is finished fitting. Since the flexible tongue piece 10 is formed integrally with the fitting portion 7, when the stopper is attached to the fitting portion 7 and the mouth portion 2 protruding from the container 1, the fitting portion 7 and the mouth portion 2 Since the air remaining during this period flows out through the through-hole 9, the cap 8 is deeply attached to the mouth portion and there is no risk of escaping. In addition, since the inside of the container is depressurized when it is cooled after being filled with the container contents at a high temperature, outside air tends to enter, but the flexible tongue piece 10 is sealed. There is no risk of bacteria entering the container.
[0019]
Cap according to claim 2 of the present invention is the cap of claim 1, further a ring-like lip 5a for press fitting to the constricted portion recess 2a of the mouth portion 2 of the container 1 on the inner periphery of the outer cylinder 5 By forming and forming a plurality of ventilation slit grooves 13 having an acute V-shaped cross section at symmetrical positions with respect to the central axis of the protrusion 5a, air remaining between the fitting portion 7 and the mouth portion 2 is vented. Since the air flows out downward through the slit groove 13, the mounting failure due to the remaining air is prevented, and the once expanded vent slit groove 13 is elastically easily restored to the original shape, and is thus fitted. The resultant force does not decrease.
Further, the fitting and holding operation is performed in a well-balanced manner.
[Brief description of the drawings]
FIG. 1 is a partially cut front view of a cap according to the invention of claim 1;
FIG. 2 is a partially cut front view of the cap according to the first aspect of the invention, wherein the mounting position of the flexible tongue is changed.
3 is a partially cut front view of a cap according to the invention of claim 2. FIG.
4 is a plan view of a main part of a cap relating to the invention of claim 2. FIG. 5 is a cross-sectional view of a known cap disclosed in Japanese Utility Model Publication No. 64-29156.
FIG. 6 is a cross-sectional view of a main part of a known cap.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Container 2 Mouth part 2a Constriction part 3 Shielding part 4 Top wall 5 Outer cylinder 5a Projection 6 Inner cylinder 7 Fitting part 8 Cap
9 holes
9a bowl-shaped recess
DESCRIPTION OF SYMBOLS 10 Flexible tongue piece 13 Ventilation slit groove 14 Pull tab 16 Outlet 20 Inner plug 30 Fitting ring 31 Horizontal ring 32 Hinge 33 Outer lid 34 Inner ring 35 Outer ring

Claims

In a cap made of synthetic resin comprising an openable shielding portion that shields the mouth protruding from the container, and a fitting portion composed of an outer cylinder and an inner cylinder connected by the top wall, the top wall has at least one Provided with a through hole, and when the fitting portion is plugged into the mouth portion of the container, it is pushed open by the air remaining between the fitting portion and the mouth portion, and the air is above the through hole. The flexible tongue that is in close contact with the upper end surface of the mouth of the container at the end of the fitting of the fitting part to prevent the outside air from entering the container and seals the through hole from the inside. A cap formed integrally with the fitting portion.

In a cap made of synthetic resin comprising an openable shielding portion that shields the mouth protruding from the container, and a fitting portion composed of an outer cylinder and an inner cylinder connected by the top wall, the top wall has at least one Provided with a through hole, when the fitting portion is plugged into the mouth portion of the container, it is pushed open by the air remaining in the fitting portion, and the air flows out from the through hole, At the end of the fitting of the fitting part, the flexible tongue piece is brought into close contact with the upper end surface of the mouth of the container to prevent the outside air from entering the container, and the through hole is sealed from the inside. A ring-shaped protrusion that is integrally formed with the joint and press-fitted into the constriction recess of the mouth is formed on the inner periphery of the outer cylinder, and a ventilation slit groove having an acute V-shaped cross section is formed on the protrusion. A cap formed at a plurality of positions symmetrical with respect to the central axis of the cap.