JPH04327145A - Cap for reduced pressure container and sealing method therefor - Google Patents

Abstract

PURPOSE:To seal up a reduced pressure container by using an easily openable cap for the reduced pressure container. CONSTITUTION:A supporting part that touches the upper end 6 of an opening of a container and a sealing part 5 of a cap whose top board 1 is extended outwardly are arranged so that they come to a position interposed between faces extending respectively from the surface and the undersurface of the top board 1. Thereby opening of the cap can be executed by relatively small force.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to a vacuum container cap and a vacuum container seal that can seal a vacuum container using the vacuum inside the container and close and open the cap with a small force. Regarding the method.

0002

2. Description of the Related Art As conventional caps for vacuum containers, many caps for sealing the inside of containers are known, such as those disclosed in Japanese Patent Publication No. 1-59179, Japanese Utility Model Publication No. 45-27915, and Japanese Patent Application Laid-open No. 57-22825. ing. In these known caps, for example, a convex cap top plate is fitted inside the open end of the container, and the vacuum inside the container is used to spread the cap top plate to obtain a pressure-bonding force for sealing inside the container. In addition, in order to obtain a seal under normal pressure, the cap top plate, which is slightly wider than the diameter of the opening end of the container, is pushed into the container, and the seal is created using a pressure force that causes the deformation of the cap top surface to return to its original state. When the inside of the container is made into a high vacuum, these caps have an even stronger crimp force, resulting in a sealing effect. However, on the other hand, there is a drawback that a large torque is required when opening the bottle. On the other hand, if a cap with a flat top plate is used, the top surface will bend inward due to the vacuum, and the 45° tapered surface, which is the sealing surface of the cap, will be strongly pressed against the open end of the container. Since the top plate of the seal part has no wall thickness and its shape makes it easy to be drawn into the inner surface, the effect of lifting the top plate by lifting the cap is small, and vacuum breakage is less likely to occur. Therefore, there is a drawback that the opening torque increases significantly when the cap is strongly pressed in a high vacuum.

0003

[Problem to be Solved by the Invention] The above conventional technology is
In either case, the outer circumferential wall of the cap or the inner circumferential wall provided inside the cap is pressed against the circumferential wall of the opening of the container to seal the inside. Because of this structure, in order to always align and seal the container and the lid, it was necessary to use mechanical force, such as a screw structure, to tighten the container so strongly that the lid was slightly deformed. Once the lid is closed, the vacuum is difficult to break, as described above, and a large amount of force is required to close the lid, and a large torque must also be applied to remove the lid. In other words, since the surface contact friction between the lid and the peripheral wall of the container is large due to the sealing with this structure, the opening torque inevitably has to be quite large.

To explain in detail, when attempting to open a conventional cap when the inside of the container is vacuum-packed, the vacuum cannot be removed unless the top of the cap, which is fitted inside the container, is pulled up to the top of the opening end of the container. cannot be destroyed. If destruction occurs, the cap is easily opened. However, until then, the cap must be lifted against the force of drawing the cap into the container and the friction caused by the seal portion being pressed against the inner wall of the opening end of the container. There are problems such as having to turn the cap many times to obtain the amount of lift that destroys the vacuum, or the cap being too tight and not turning, and even if the cap is turned, it quickly becomes a cap that does not feel free. There is. This tendency is especially true when the degree of vacuum inside the container is high and the deformation of the top surface is large. These drawbacks are caused by the basic means of sealing the container opening with the lid and the structure of the container opening and lid.

[0005]

[Means for Solving the Problems] The present inventor has researched a cap for a vacuum container that can be closed and opened with a small force, and has made it possible to open and close the cap with a small force by utilizing the vacuum of the container. I knew I could get it. In other words, the vacuum container is automatically sealed when the sealing surface of the cap comes into contact with the inner peripheral surface of the opening of the container, so no other force or structure is required, and unless the vacuum is broken, sealing will occur. This alone is enough to maintain it. In other words, it is important that the sealing part eliminates the action of excessive external force. These external forces unnecessarily make it difficult to open the container, which is inconvenient. In order to utilize such reduced pressure, it is impossible to use a cap with a conventional structure, and a special structure is required to seal the fitting part of the cap that fits into the opening of the container and the structure of the top plate of the cap using reduced pressure. The present invention was completed by clarifying that the structure must be made as follows.

[0006] The present invention has the following features: 1. A disk-shaped top plate (1) projecting outward in an arcuate manner, a cylindrical outer circumferential wall (2) connected to the periphery of the top plate and hanging downward, and an inner wall. A fitting groove (4) that fits into the opening of a ring-shaped container surrounded by a peripheral side wall and a cylindrical outer peripheral wall is provided, and a ring-shaped container that hangs downward is arranged on the peripheral edge of the lower surface of the top plate. In the cap, the cylindrical outer circumferential wall and the inner circumferential side wall are arranged, and a fixing part is arranged on the inner circumferential surface of the cylindrical outer circumferential wall to join with a fixing part provided on the opening side wall surface of the container. (A) A top surface (7) of the fitting groove is formed at a position between the top plate and the top plate extending from both sides of the arcuate top plate, and is in contact with the opening end surface of the container. A cap for a reduced-pressure container that is provided with a support part that restrains a top plate and (B) a seal contact part consisting of a seal surface (5) formed by the outer peripheral surface of the inner peripheral side wall that comes into contact with the inner peripheral surface of the upper end of the opening of the container. 2. The cap for a reduced pressure vessel according to claim 1, wherein the sealing surface of the inner circumferential side wall of the cap is a slope inclined toward the center of the cap. 3. The sealing surface of the cap is in an outwardly convex arc shape.
The cap for a reduced pressure container according to claim 1 or 2. 4. The cap for a reduced pressure container according to any one of claims 1 to 3, wherein the ring-shaped inner peripheral side wall is integrally formed with the top plate. 5. The cap for a reduced pressure container according to any one of claims 1 to 4, wherein the fixing portion provided on the inner circumferential surface of the cylindrical outer circumferential wall of the cap is a screw. 6. 6. The cap for a reduced pressure container according to claim 1, wherein the lower end portion of the sealing surface of the cap projects below a surface extending from the lower surface of the top plate. 7. 7. The cap for a vacuum container according to claim 1, wherein the top plate projecting outward in an arcuate manner has a curved surface or a polygonal pyramidal convex surface. 8. A disk-shaped top plate that extends outward in a convex arc shape (1
), a downwardly hanging cylindrical outer peripheral wall (2) connected to the periphery of the top plate, and a downwardly hanging ring-shaped inner peripheral side wall (3) installed at the lower peripheral edge of the top plate. A fitting groove (4) that fits into the opening of a ring-shaped container surrounded by a peripheral side wall and a cylindrical outer peripheral wall is provided, and a fitting groove (4) is provided on the inner peripheral surface of the cylindrical outer peripheral wall on the side wall surface of the opening of the container. A screw cap in which a fixing part is arranged to be connected to a fixing part, which is located between the cylindrical outer circumferential wall and the inner circumferential side wall, and is sandwiched between the respective extension surfaces of the upper and lower surfaces of the top plate that extends in an arc shape. (A) A support portion that forms the top surface (7) of the fitting groove and abuts against the opening end surface of the container to restrain the top plate, and (B) a sealing surface (5) formed by the outer peripheral surface of the inner peripheral side wall. A decompression container cap provided with a seal abutting portion consisting of a seal contact portion is placed over the top surface of the open end of the container, and the top surface (6) of the open end of the container is brought into contact with the top surface of the ring-shaped fitting groove. While supporting the cap, the sealing surface of the inner circumferential side wall is brought into contact with the periphery of the open end of the container, and the seal abutting portion is restrained by the open end of the container to form a contact sealing surface between the support surface of the fitting groove and the inner circumferential side wall. A vacuum container sealing method that seals the container by suctioning it into the container by reducing the pressure inside the container. ” related.

[0007]

[Function] The first feature of the present invention is that the upper top plate of the cap is outwardly convex. This is because if the inside of the container is under reduced pressure, the flat top plate will deform into a convex shape inward, resulting in increased friction between the cylindrical circumferential wall of the cap and the circumferential wall of the container, resulting in a disadvantage that the opening torque increases. The top plate of the cap may be convex in a curved arc shape, or may be convex in a polygonal pyramid shape. A second feature of the present invention is that the seal abutting portion and the support portion of the cap are located within an extension of the top and bottom surfaces of the top plate. A third feature of the present invention is that the outer circumferential surface of the inner circumferential side wall of the cap is formed into a slope inclined toward the center of the cap to form a contact sealing surface. With the fitting groove in the above position, when the fitting groove of the cap is fitted into the opening of the container, the contact sealing surface of the cap comes into contact with the inner peripheral edge of the end of the opening of the container, and the pressure inside the container is reduced. seal more closely. Although the contact width between the two is narrow, since the position is a special position that is an extension of the upper and lower top plate surfaces,
The pushing down force due to the reduced pressure applied to the top plate, in other words, the force to pull the cap into the container, acts perpendicularly to the contact sealing surface that forms the slope, and this force is divided into vertical and horizontal forces on the slope. The horizontal force component pushes the sealing surface toward the periphery of the cap and against the periphery of the opening of the container, while the vertical component of force forces the sealing surface downwardly, also against the periphery of the opening of the container. Due to the action of these two component forces, sealing is achieved very well, although the width is narrow. Since there is no tightening by any other means, the contact area is small, and the friction is low, the bottle can be opened with a small torque. Furthermore, the support portion provided in the fitting groove of the cap and restraining the top plate prevents deformation of the top plate and prevents an increase in the frictional force between the inner circumferential wall of the cap and the circumferential wall of the container.

The above features will be explained in detail. The reason why the seal abutting part of the cap must be within the extension line of the upper and lower top plates When a vacuum cap is sealed with a vacuum inside the container, the top surface of the cap will be drawn into the container by atmospheric pressure. There is a force at work. The cap is strongly pressed against the upper part of the open end of the container by the force of this vacuum. Therefore, a top surface at the open end of the container is required to support vertical forces. Furthermore, by making the top surface of the cap dome-shaped, the deflection of the top surface deformed by the vacuum is transformed into horizontal displacement, which is restrained by the inner surface of the opening end of the container, resulting in the effect of crimping a part of the cap. There is. When modeling this mechanism, the open end of the container that contacts the cap is divided into a support surface and a sealing surface. Consider the vacuum cap based on the positional relationship between the extension line of the top plate surface, the support part, and the seal part.

[0009] Due to the effect of the seal, the more the seal portion is removed from within the extension line, the more the cap is bent and deformed to be crimped, making it impossible to efficiently utilize horizontal force. In addition, since the seal mainly uses repulsive force due to bending deformation of the material, deterioration such as creep is likely to occur and the seal function is likely to be lost. b Effect of rotational moment at the support point When the cap has an external thread on its cylindrical outer wall and there is an extension of the upper and lower surfaces of the top plate inside the support point, a rotational moment is generated at the support part due to the vacuum force. This has the effect of pulling up the cylindrical outer wall, thereby tightening the threads. This causes the opening torque to become high. c. Ease of opening due to differences in lift movement Although the details will be explained in a comparative example, there are cases in which both the support part and the seal part are within the extension line of the top and bottom surfaces of the top plate, and cases in which only the seal part is included. If we look at the case where the top plate is within the extension line of the upper and lower surfaces and the support part is on the periphery of the cap, in the latter case, when turning the cap to open it, it is difficult to break contact between the inner surface of the container and the cap seal part. requires a long lift amount. During this time, the cap must be moved against atmospheric pressure and friction with the inner surface of the container, making the cap difficult to open. In the former case, decompression failure occurs with a small amount of movement,
Opening becomes easier. The wider the cap shape and the higher the degree of vacuum, the more difficult it is to open the latter form. in this way,
By providing the sealing part of the cap around the top plate, which is sandwiched between the upper and lower surfaces of the top plate of the cap, the reduced pressure inside the container can be used to reduce the pressure at the sealing surface of the inner peripheral wall of the cap. This is a new sealing method discovered for the first time by the inventor of the present invention, in which the force used to push down the top plate is divided into horizontal and vertical directions, and it is effective in opening and closing the stopper with a small force. If the inner circumferential edge of the opening of the container is brought into contact with the sealing surface of the inner circumferential wall of the cap as an inclined surface, the seal will be better, but since the contact width is narrow, the friction will not be large and opening will be easy. The sealing surface of the cap may be arcuate rather than sloped. In this case as well, the force is divided into horizontal and vertical directions at the contact area with the opening rim of the container.
A similar sealing effect is achieved.

[0010] The cap of the present invention provides a sufficient seal when it is placed over the opening of the container, but it is also possible to provide a suitable screw on the inner surface of the cylindrical outer peripheral wall of the cap and engage it with the screw on the outer periphery of the container. It's okay. This structure does not tighten the cap onto the container, but makes it easier to lift the cap, and is used when re-capping a container that has been opened and depressurized. This fixing also has the effect of preventing the seal from breaking due to impact during handling. This is because if the reduced pressure is removed, the closure utilizing reduced pressure, which is a feature of the present invention, will no longer be possible. The inner peripheral wall of the cap of the present invention may be integrally molded with the cap, but a ring-shaped peripheral wall having a triangular or semicircular cross section may be separately molded and arranged. The cap of the present invention may be made of synthetic resin or metal, but if it is molded from a hard material, it is preferable to arrange an inner circumferential wall separately molded from synthetic resin. The contact sealing surface of the inner circumferential wall of the cap is not a packing, but the top plate of the cap is drawn into the container by reduced pressure and seals by coming into close contact with the periphery of the opening of the container. If so, it is sufficient. Again, the seal of the present invention is not achieved by surface contact between the circumferential wall of the container and the circumferential wall of the cap. Sealing is achieved by the contact between the top surface of the fitting groove provided at a specific position of the cap and the top surface of the opening end of the container due to reduced pressure, and the contact between the contact sealing surface of the inner circumferential wall of the cap and the narrow width around the periphery of the container opening. , these contacts are not surface contacts, but rather linear contacts. The cap of the present invention restrains the deflection of the top surface of the cap due to vacuum at the open end of the container to prevent deformation, so there is little friction between the cap and the peripheral wall of the container, and the cap can be lifted while maintaining its shape when rotated. Therefore, contact between the sealing portions is easily broken and vacuum breakdown occurs quickly, resulting in a vacuum cap that is easy to open and gives a sense of release. On the other hand, with flat-shaped caps, the top surface is drawn into the container and bends and deforms, so even if you lift the deformed cap, the contact between the seals is difficult to break and it is difficult to release. . The cap rotates but does not open.

[0011]

EXAMPLES Next, the present invention will be explained in detail based on examples, and a comparative test with a conventional cap will be shown. FIG. 1 shows an embodiment of the present invention, and shows a cross-sectional front view of a container covered with a cap. FIG. 2 is an enlarged view showing the sealed state of the cap and the upper end of the opening of the container shown in FIG. As is clear from FIGS. 1 and 2, the top plate 1 of the cap is upwardly convex. Reference numeral 2 denotes a downwardly hanging cylindrical outer wall connected to the periphery of the top plate, and a fixing protrusion 9 is arranged on the inner circumferential side to join with a fixing part on the outer periphery of the container. The container may be fixed to the container in the form of a screw, or simply by combining the upper and lower surfaces of the convex portions. Reference numeral 3 denotes a ring-shaped inner circumferential wall installed at the lower peripheral edge of the top plate and hanging downward, and a fitting groove 4 is formed between the inner circumferential wall and the outer wall to fit with the opening upper end of the container. There is. Reference numeral 7 designates the top surface of the fitting groove, and when the cap is covered, it comes into contact with the open upper end 6 of the container, thereby forming a support portion that restrains and supports the top plate of the cap. Reference numeral 5 denotes the outer circumferential surface of the inner circumferential wall, which is a slope slanting diagonally downward, forming a sealing surface. Reference numeral 8 denotes the inner circumferential surface of the upper end of the container opening, which is a slope slanting inward of the container. A seal abutting portion is formed between the cap sealing surface 5 and the inner circumferential surface 8 of the upper end of the container opening. When the cap is placed on the container, the upper end of the opening of the container is inserted into the fitting groove, and the upper end surface 6 of the opening comes into contact with the top surface 7 of the fitting groove of the cap to restrain and support the top plate of the cap. Further, the sealing surface 5 of the inner circumferential wall 3 of the cap comes into contact with the inner circumferential surface 8 of the upper end of the opening of the container. The container is thus sealed between the support and the sealing surface 5. Since the inside of the container is under reduced pressure, a force acting on the top plate draws it into the container. Then, the upwardly convex top plate is pushed downward and spread laterally, producing a so-called toggle effect, and the sealing surface 5 is pressed against the inner circumferential surface 8 of the upper end of the opening to perform sealing. On the other hand, the upper end surface 6 of the container opening and the top surface 7 of the fitting groove are in contact with each other, but this portion is responsible for supporting the top plate rather than a seal, and restrains the top plate to prevent unnecessary deformation.

With this structure, sealing is performed exclusively between the sealing surface of the cap and the narrow inner peripheral surface of the upper opening of the container, and the supporting portion prevents unnecessary deformation of the top plate.
The deformation prevents an increase in friction at the seal abutting portion and reduces the force that breaks the seal, so-called opening force. That is, since there is little deformation of the top plate, the friction of the support part is small when the cap is opened, and the friction of the seal part is also small, so the cap can be raised with a small torque. When the seal contact part separates, the vacuum is broken and the cap can be opened easily. As can be understood from this example, there is a support part that restrains the top plate and prevents unnecessary deformation of the top plate, and a support part that restrains the top plate and prevents unnecessary deformation of the top plate. Since the restraint of the top plate becomes weaker and the deformation of the top plate increases, the opening torque does not become smaller. The upper part 10 of the fitting groove on the outer peripheral edge of the top plate increases the binding force of the top plate,
It is preferable to make the top plate thick in order to prevent unnecessary deformation of the top plate.

FIG. 3 shows another embodiment. In this embodiment, the lower end of the ring-shaped inner circumferential wall of the cap extends below the extension line of the top and bottom surfaces of the top plate. Even with such an inner peripheral side wall, if the seal contact part and the support part are within the range of the extension line of the top and bottom surfaces of the top plate, unnecessary deformation of the top plate will be prevented by the support part and the seal will be completed completely. At the same time, the opening torque can be reduced.

FIG. 4 shows another embodiment in which the sealing surface 5 of the inner circumferential wall of the cap is an arcuate curved surface. This sealing surface has a narrow width, is almost linear, and comes into contact with the inner circumferential surface of the upper end of the opening of the container, which has the advantage of reducing the opening force.

FIG. 5 shows a comparative example in which the top plate is flat,
The top plate is pushed into the container and is greatly deformed into a downward concave shape, the cylindrical outer wall opens outward, and the opening upper end 6 of the container does not support the top surface 7 of the cap, so no supporting part is formed and the seal abuts. The joints can be pressed very hard and the seal will not break. Therefore, the opening torque becomes extremely large, making it difficult to open the cap.

FIG. 6 shows another comparative example in which the supporting portion of the cap and the abutting sealing surface are not in a plane extending from the upper and lower surfaces of the top plate, but are located closer to the center of the cap than the plane. With such a structure, even if the top plate has an outwardly convex arc shape, the top plate is pushed into the container and is greatly deformed into a downward concave shape, and the cylindrical outer wall opens outward, causing the opening upper end 6 of the container to open. does not support the top surface 7 of the cap, so no support part is formed, and the seal abutting part is pressed very strongly and the seal is not broken. therefore,
The opening torque becomes extremely large, making it difficult to open the cap.

Next, a comparative test and its results will be shown in order to explain the effects of the present invention. Comparative Test 1 Opening Torque Test The caps used are as shown in Figure 2 for Example 1, Figure 3 for Example 2,
Comparative Example 1 is the cap shown in FIG. 5, and Comparative Example 2 is the cap shown in FIG. 6, which is a screw cap molded from polypropylene resin with a screw provided on the inner peripheral surface of the outer wall of the cap. On the other hand, the container was a screw bottle made of stainless steel with an inner diameter of 59 mm and equipped with a screw on the outer periphery of the upper end of the opening. The surface forming the abutting seal on the inner periphery of the open end of the container is a slope with a width of 1.1 mm, and the surface supporting the cap is 0.7 mm wide. The resin weight of the cap and the thickness of the top plate are as shown in Table 1.

[0018]

[Table 1]

In the test, capping was performed at an opening torque of 40 [kgf·cm], and the opening torque was measured by hand. The test results are shown in Table 2.

[0020]

[Table 2]

[Note] The opening torque is (Kgf・cm)
It was expressed as From this test result, it is understood that the cap of the present invention can be opened with a small force. It is clear that if the top plate is flat, a large amount of force is required to open the bottle. Furthermore, it is understood that even if the top plate is made to protrude in an arc shape, if there is no support part that restrains and supports the top plate at the opening of the container, the opening torque will be large. Comparative test 2 Top plate deflection test Test method: Measure the deflection at the center of the cap. The results are shown in Table 3.

[0022]

[Table 3]

[Note] The amount of deflection is shown in (mm). This test shows that when the top plate is flat, the deflection increases and the top plate deforms. Furthermore, even if the top plate is outwardly convex, if the cap does not have a supporting portion, the top plate will sag significantly. It is understood that when the top plate bends, the adhesion force of the abutting seal portion increases and the friction also increases, so a large force is required to open the bottle.

[0024]

[Effects] The present invention facilitates opening of the cap by arranging the abutting seal portion and the support portion of the cap at a position sandwiched between the extension lines of the upper and lower surfaces of the top plate.

[0025]

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing a covered state of the cap of the present invention.

FIG. 2 is a partial cross-sectional view of the cap of the present invention.

FIG. 3 is a partial cross-sectional view of the cap of the present invention.

FIG. 4 is a partial cross-sectional view of the cap of the present invention.

FIG. 5 is a partial cross-sectional view of a cap of a comparative example.

FIG. 6 is a partial cross-sectional view of a cap of a comparative example.

[Explanation of symbols]

1...Top plate 2...Cylindrical outer wall ３　…　Inner peripheral wall 4…Fitting groove 5... Seal surface 6... Opening top end surface 7...Top surface 8... Inner circumference of the upper end of the opening 9...Fixed protrusion 10... Upper part

Claims (8)

[Claims] Claim 1: A disk-shaped top plate (1) projecting outward in an arcuate manner, a cylindrical outer peripheral wall (2) connected to the periphery of the top plate and hanging downward, and an inner peripheral side wall and a cylindrical-shaped top plate (1). A fitting groove (4) that fits into the opening of the ring-shaped container surrounded by the outer circumferential wall is provided, and a downwardly hanging ring-shaped inner circumferential side wall ( 3), in which a fixing part is arranged on the inner circumferential surface of the cylindrical outer circumferential wall to connect with a fixing part provided on the opening side wall of the container, at a position between the cylindrical outer circumferential wall and the inner circumferential side wall. In addition, the top surface (7) of the (A) fitting groove is formed at a position where the upper and lower surfaces of the top plate projecting in an arc shape are sandwiched by the respective extended surfaces, and the top surface (7) of the fitting groove is formed in contact with the opening end surface of the container to restrain the top plate. A cap for a reduced-pressure container, which is provided with a support part and (B) a seal contact part consisting of a seal surface (5) formed by the outer peripheral surface of the inner peripheral side wall that comes into contact with the inner peripheral surface of the upper end of the opening of the container. 2. The cap for a reduced pressure container according to claim 1, wherein the sealing surface of the inner circumferential side wall of the cap is a slope inclined toward the center of the cap. 3. The cap for a vacuum container according to claim 1, wherein the sealing surface of the cap has an outwardly convex arc shape. 4. The cap for a vacuum container according to claim 1, wherein the ring-shaped inner peripheral side wall is integrally formed with the top plate. 5. The cap for a reduced pressure container according to claim 1, wherein the fixing portion provided on the inner circumferential surface of the cylindrical outer circumferential wall of the cap is a screw-like screw. 6. The cap for a vacuum container according to claim 1, wherein the lower end portion of the sealing surface of the cap projects below a surface extending from the lower surface of the top plate. 7. The cap for a vacuum container according to claim 1, wherein the top plate projecting outward in a convex arc shape has a curved surface or a polygonal pyramidal convex surface. 8. A disk-shaped top plate (1) projecting outward in an arcuate manner, a cylindrical outer peripheral wall (2) connected to the periphery of the top plate and hanging downward, and a lower surface of the top plate. A fitting groove (4) consisting of a ring-shaped inner circumferential wall (3) installed at the peripheral edge and hanging downward, and fitting into the opening of the ring-shaped container surrounded by the inner circumferential side wall and the cylindrical outer circumferential wall. A screw cap is provided with a fixing part arranged on the inner circumferential surface of the cylindrical outer circumferential wall to connect with a fixing part provided on the opening side wall surface of the container, the screw cap having a fixing part arranged on the inner circumferential surface of the cylindrical outer circumferential wall, the fixing part being connected to the fixing part provided on the opening side wall surface of the container, At the position where both the upper and lower sides of the arc-shaped top plate are sandwiched between the respective extended surfaces,
(A) Consists of a support part that forms the top surface (7) of the fitting groove and restrains the top plate by coming into contact with the opening end surface of the container, and (B) a sealing surface (5) formed by the outer peripheral surface of the inner peripheral side wall. A decompression container cap provided with a seal contact portion is placed over the top surface of the open end of the container, and the top surface (6) of the open end of the container is brought into contact with the top surface of the ring-shaped fitting groove. At the same time, the sealing surface of the inner circumferential side wall is brought into contact with the periphery of the open end of the container, and the seal abutting portion is restrained by the open end of the container, so that the contact sealing surface of the supporting surface of the fitting groove and the inner circumferential viewing wall is in contact with the periphery of the opening end of the container. A vacuum container sealing method that seals the container by suctioning it into the container.