JP4630131B2 - Container lid and sealing method - Google Patents

Description

  The present invention relates to a container lid composed of a thin metal shell and a synthetic resin packing, and a sealing method for sealing the container neck by mounting the container lid on the mouth neck of the container.

  As is well known, recently, as a container for beverages such as coffee, it has a mouth and neck part in which a curl is formed at the upper end and a male thread and a locking jaw part are formed on the outer peripheral surface. Metal thin plate containers are widely used in practical use. As a container lid particularly suitable for such a metal sheet container, for example, as disclosed in Patent Documents 1 and 2, a container cover composed of a metal sheet shell and a synthetic resin packing is used. ing. The shell has a circular top wall and a skirt wall depending from the periphery of the top wall. The skirt wall is formed with a circumferential break line extending in the circumferential direction, and the skirt wall is divided into a main part above the circumferential break line and a tamper evidence skirt below the circumferential break line. Has been. The packing has a disk shape as a whole.

When sealing the mouth and neck by attaching a container lid to the mouth and neck of the container, the container lid is fitted on the mouth and neck and pressed downward, and the skirt wall extends from the periphery of the top wall of the shell. The shoulder region leading to the upper end of the sleeve is deformed radially inward and downward to bring the packing into close contact with the mouth and neck. While maintaining this state, a female thread is formed in the main part of the shell skirt wall corresponding to the male thread of the mouth and neck, and the lower part of the tamper evidence hem is also deformed radially inward. Lock to the jaw of the mouth and neck. When opening the mouth and neck, rotate the container in the opening direction. Thus, since the female thread of the shell is moved along the male thread of the mouth and neck, the container lid is raised with the rotation. However, the tamper evidence hem is prevented from rising because the lower part is locked to the locking jaw of the mouth and neck, and therefore considerable stress is generated in the circumferential break line, and the circumferential break line breaks. As a result, the tamper evidence hem is separated from the main part of the skirt wall. After that, the tamper evidence hem is left in the mouth and neck, the container lid is raised with rotation, is detached from the mouth and neck, and the mouth and neck are opened. If an axial break line is formed at the tamper evidence hem, a portion of the circumferential break line is maintained without breaking, the axial break line is broken, and the tamper evidence skirt is The container lid is developed from an endless annular shape to an end-band shape, and the entire container lid including the tamper evidence skirt is detached from the mouth and neck.
JP 2001-139053 A Japanese Patent Laid-Open No. 2003-175972

  Thus, according to the experience of the present inventors, the container lid composed of the thin metal shell and the synthetic resin packing is mounted on the mouth and neck of the container without being limited to the container lid of the above-described form. When the container's mouth and neck are sealed, for example, when a container with a container lid attached to the mouth and neck is dropped to the floor surface in a substantially inverted state and a considerable impact is applied to the shoulder region in the shell of the container lid It has been found that although the sealing damage is fine, it progresses gradually, and after several weeks, for example, it tends to become clear that the sealing of the mouth and neck is damaged. The phenomenon that it becomes clear that the sealing has been damaged after a relatively long time has passed since the impact was applied is generally referred to as “slow leak” or “micro leak”.

  The present invention has been made in view of the above-mentioned facts, and the main technical problems thereof are a container lid composed of a thin metal plate shell and a synthetic resin packing, and a mouth and neck portion of the container using such a container lid. It is intended to improve the impact resistance by improving the sealing method for sealing the seal so that the seal is not damaged even if a considerable impact is applied to the shoulder region of the shell.

  As a result of intensive studies, the present inventors have found that the main technical problem can be achieved by forming an annular protrusion protruding inward in the shoulder region of the shell.

That is, according to the present invention, as a container lid that achieves the main technical problem described above, it is composed of a thin sheet metal shell and a synthetic resin packing, and the shell is a circular top wall and a skirt that hangs down from the periphery of the top wall And the packing has a disk shape as a whole, and is attached to the mouth and neck of the container to seal the mouth and neck of the container from the periphery of the top wall of the shell. In the container lid in a form in which the shoulder region reaching the upper end of the skirt wall is deformed radially inward and downward,
A container lid is provided, characterized in that an inwardly projecting annular ridge is formed in the shoulder region of the shell.

Preferably, the annular ridge is formed at the peripheral edge of the top wall and is opposed to the upper surface of the packing that extends substantially horizontally. The cross-sectional shape of the annular ridge is preferably an arc shape. The protruding amount of the annular ridge may be 0.2 to 0.8 mm. The packing is preferably non-adhering to the shell. Preferably, the shoulder region of the shell is deformed by pressing with a tool having a pressing inclined surface inclined at an inclination angle α of 5 to 30 degrees with respect to the horizontal. Alternatively, the shoulder region of the shell is deformed by pressing with a tool having a pressing surface acting on a radially outer side of the annular ridge in the shoulder region.

According to the present invention, as a preferable sealing method for achieving the main technical problem, a sealing method for sealing the mouth and neck by attaching a container lid to the mouth and neck of the container, The shell comprises a thin metal plate shell and a synthetic resin packing, the shell having a circular top wall and a skirt wall depending from the periphery of the top wall, and the packing has a disk shape as a whole. In the sealing method in which the shoulder region from the peripheral edge of the top wall to the upper end of the skirt wall is deformed radially inward and downward after the container lid is fitted on the part,
An inwardly projecting annular ridge is formed in the shoulder region of the shell, and a tool having a pressing inclined surface inclined at an inclination angle α of 5 to 30 degrees with respect to the horizontal is used for the shell. There is provided a sealing method characterized in that the shoulder region is deformed by pressing the shoulder region.

According to the present invention, as a preferable sealing method for achieving the main technical problem, a sealing method for sealing the mouth and neck by attaching a container lid to the mouth and neck of the container, The shell comprises a thin metal plate shell and a synthetic resin packing, the shell having a circular top wall and a skirt wall depending from the periphery of the top wall, and the packing has a disk shape as a whole. In the sealing method in which the shoulder region from the peripheral edge of the top wall to the upper end of the skirt wall is deformed radially inward and downward after the container lid is fitted on the part,
An inwardly projecting annular ridge is formed on the peripheral edge of the top wall of the shell, and the shoulder is formed by a tool having a pressing surface that acts on a radially outer side of the annular ridge in the shoulder region. There is provided a sealing method characterized in that the shoulder region is deformed by pressing the region.

  According to the container lid and the sealing method of the present invention, as clearly understood from the examples and comparative examples described later, the impact resistance is improved, and the seal is sealed even when a considerable impact is applied to the shoulder region of the shell. The damage is sufficiently suppressed or avoided.

  Hereinafter, a preferred embodiment of a container lid configured according to the present invention and a preferred embodiment of a sealing method using the same will be described in detail with reference to the accompanying drawings.

  Referring to FIG. 1 illustrating a preferred embodiment of a container lid constructed in accordance with the present invention, the container lid, generally designated by the numeral 2, is formed from a suitable metal sheet such as an aluminum-based alloy sheet. The shell 4 and the shell 4 are separately composed of an appropriate synthetic resin, for example, a packing 6 formed of a blend resin of styrene elastomer and polypropylene.

  The shell 4 has a circular top wall 8 and a skirt wall 10 that is generally cylindrical and hangs down from the periphery of the top wall 8. The peripheral portion of the top wall 8 is connected to the upper end portion of the skirt wall 10 via a boundary portion 12 having an arc shape in the sectional view, and the peripheral portion of the top wall 8, the boundary portion 12 and the upper end portion of the skirt wall 10 are A so-called shoulder region 14 is formed.

  It is important that the shoulder region 14 of the shell 4 is formed with an annular ridge 16 projecting inwardly. In the illustrated embodiment, the top wall 8 has a circular central recess 18 that extends substantially horizontally, an intermediate portion 20 having an inverted frustoconical shape, and an outer annular portion 22 that extends substantially horizontally. The strip 16 is formed in the outer region of the outer annular portion 22, that is, the peripheral portion of the top wall 8. The cross-sectional shape of the annular ridge 16 is preferably an arc shape. The protrusion D1 of the annular ridge 16 is preferably about 0.2 to 0.8 mm.

  A circumferential break line 24 is formed in the lower part of the skirt wall 10 of the shell 4, and the skirt wall 10 has a main portion 26 above the circumferential break line 24 and a tamper evidence below the circumferential break line 24. It is partitioned into a skirt portion 28. In the illustrated embodiment, an annular bulging portion 30 is formed in the lower part of the skirt wall 10, and the annular bulging portion 30 has a circumferentially spaced slit 32 extending between the slit 32 and the circumferentially extending slit 32. The circumferential direction fracture line 24 comprised from the bridge part 34 which exists in is arrange | positioned. An annular groove 36 is formed in the main portion 26 of the skirt wall 10. A plurality of air holes 38 are disposed above the annular groove 36 at intervals in the circumferential direction. Each of the air holes 38 forms a lateral slit 40 that extends substantially horizontally at intervals in the circumferential direction, and generates an inward displacement portion 42 by forcing the lower portion of the lateral slit 40 radially inward. It is formed by doing.

  The description will be continued with reference to FIG. 1. The packing 6 has a disk shape as a whole, and has a central immersion portion 44, an inverted frustoconical intermediate portion 46, and a peripheral portion 48 that extend substantially horizontally. The upper surface of the peripheral edge 48 extends substantially horizontally outward in the radial direction, and then extends radially outward and downward in an arc in the cross-sectional view. Two annular seal rings, that is, an annular outer seal ring 50 and an annular inner seal ring 52 are formed on the lower surface of the peripheral edge portion 48 of the packing 6. The outer portion of the peripheral edge portion 48 of the packing 6 is increased in thickness, and the outer seal ring 50 is extended downward from the outer portion where the thickness is increased. An annular receiving surface 54 that extends substantially horizontally is defined on the radially outer side of the outer seal ring 50. The inner seal ring 52 that is located radially inwardly with respect to the outer seal ring 50 extends downward from the inner side of the peripheral edge 48. Such a packing 6 is inserted into the shell 4, and the outer peripheral edge of the packing 6 is elastically deformed, so that the annular receiving surface 54 passes through the inner displacement portion 42 of the shell 4 and is positioned above it. It is done. The annular ridge 16 formed on the shell 4 is conveniently positioned opposite the substantially horizontally extending portion of the upper surface of the peripheral edge 48 of the packing 6.

  FIG. 2 also shows the mouth / neck portion 56 of the container to which the container lid 2 is applied together with the container lid 2 described above. The mouth / neck portion 56 of the container, which can be formed from a chromic acid-treated steel sheet, an aluminum-based alloy sheet, or a tin sheet, has a substantially cylindrical shape as a whole, and a male thread 58 is formed at the center in the axial direction. A locking jaw 60 having an annular bulging shape is formed below the male thread 58. The upper part of the mouth-and-neck part 56 has a truncated cone shape whose diameter gradually decreases upward, and an outer curl 62 is formed at the upper end of the mouth-and-neck part 56. The curl 62 extends upward in the cross-sectional view, extends in an arc shape upward and radially outward, extends in an arc shape downward and radially outward, extends downward, and downward and radially inward. It extends in a circular arc shape and further extends in a circular arc shape upward and radially inward. Since the metal container itself provided with such a mouth-and-neck part 56 is well known, a detailed description of the metal container itself is omitted in this specification.

  An example of the mounting operation for mounting the container lid 2 on the container neck 56 and sealing the mouth neck 56 will be described as follows. When the contents to be filled in the container are coffee, normally, after filling the container with coffee, nitrogen gas is introduced into the container to remove the air in the upper space of the container from the container. At the same time, water vapor is introduced into the container, and then the container lid 2 is fitted onto the mouth-and-neck portion 56. When the water vapor is liquefied due to the temperature drop, the inside of the container fitted with the container lid 2 is decompressed, and the container lid 2, particularly its packing 6, is sucked by this decompression, and as shown in FIG. The inner seal ring 52 is advanced into the mouth-and-neck portion 56, and thus the mouth-and-neck portion 56 is temporarily sealed. In such a state, the packing 6 is raised relative to the shell 4, and the annular ridge 16 formed on the outer annular portion 22 of the top wall 8 of the shell 2 is formed on the upper surface of the peripheral portion 48 of the packing 6. It can be brought into contact.

  Next, as shown in FIG. 3, a horizontal pressing surface 66 that extends substantially horizontally, a pressing inclined surface 68 that inclines downward from the outer peripheral edge of the horizontal pressing surface 66 radially outward, and an outer surface of the pressing inclined surface 68. A pressing tool 64 having a vertical pressing surface 70 extending substantially vertically downward from the periphery is connected to the shoulder region 14 of the shell 4 (see FIG. 1), that is, the peripheral portion of the top wall 8 and the boundary portion 12 (see FIG. 1). And the upper end portion of the skirt wall 10, and the shoulder region 14 is immersed downward and radially inward mainly by the pressing inclined surface 68. The inclination angle α of the pressing inclined surface 68 of the pressing tool 64 with respect to the horizontal is preferably 5 to 30 degrees. As clearly shown in FIG. 3, the lower surface of the peripheral portion 48 of the packing 6 is brought into close contact with the upper portion of the outer peripheral surface of the curl 62 of the mouth and neck portion 56 to seal the mouth and neck portion 56. The annular ridge 16 formed on the top wall 8 of the shell 4 is pressed against the upper surface of the peripheral edge 48 of the packing 6 and bites there. Further, a thread forming tool 72 is applied to the skirt wall 10 of the shell 4 to form a female thread 74 along the male thread 58 of the mouth-and-neck section 56 downward from the annular groove 36 (FIG. 1). . Further, a locking tool 76 is applied to the lower part of the tamper-evidence skirt part 28 of the skirt wall 10 to force the lower part of the tamper-evidence hem part 28 inward in the radial direction, thereby locking the jaw part of the mouth-neck part 56. Lock to 60. The configuration of the thread forming tool 72 and the locking tool 76, and also the capping by them may be in a form well known to those skilled in the art, and therefore a detailed description thereof will be omitted in this specification. As described above, in a state where the container lid 2 is attached to the mouth / neck portion 56 of the container, the upper edge of the inward displacement portion 42 formed on the skirt wall 10 of the shell 4 and the annular receiving surface 54 of the packing 6. There is a gap D2 which is preferably about 0.3 to 3.5 mm in between, and the outer peripheral edge of the annular receiving surface 54 of the packing 6 is the minimum inner peripheral edge of the upper edge of the inner displacement portion 42 of the shell 4. It is positioned radially outward by a distance D3 that may be about 0.1 to 1.0 mm.

  Continuing the description with reference to FIG. 5 illustrating the state in which the container lid 2 is attached to the mouth-and-neck portion 56 as required, if the content filled in the container is coffee, it is usually as described above. After attaching the container lid 2 to the mouth / neck part 56, the container is heated to about 130 ° C. under a pressure of 0.13 MPa, for example, and sterilized by retort. To do. The cooling water sprayed into the container enters the shell 4 through the vent hole 38 formed in the skirt wall 10 of the shell 4, and the annular ridge formed on the top wall 8 of the shell 4, particularly the peripheral edge thereof. 16 is pressed against the upper surface of the peripheral edge portion 48 of the packing 6, so that it is certain that the cooling water enters between the central recess portion 18 of the top wall 8 of the shell 4 and the central recess portion 44 of the packing 6. To be blocked.

  When the container neck 56 is opened and the contents are consumed, the shell 4 of the container lid 2 is rotated in the opening direction, that is, counterclockwise as viewed from above in FIG. Thus, the shell 4 is raised along with the rotation by the cooperation of the male thread 58 of the mouth and neck portion 56 and the female thread 74 of the shell 4. However, the tamper-evidence skirt portion 28 of the shell 4 is locked to the locking jaw portion 60 of the mouth-and-neck portion 56, so that the ascent is prevented and the circumferential direction formed on the skirt wall 10 of the shell 4 is thereby prevented. A considerable stress is generated in the bridging portion 34 of the breaking line 24, and the circumferential breaking line 24 is broken. When the circumferential break line 24 is broken, the packing 6 that is in close contact with the mouth and neck portion 56 is formed separately from the shell 4, so that it is in close contact with the mouth and neck portion 56. Since only the shell 4 can be rotated without the packing 6 being rotated, the circumferential break line 12 can be broken sufficiently easily without requiring excessive torque.

  After the circumferential break line 24 is broken, the tamper evidence skirt 28 remains, and the top wall 8 of the shell 4 and the main portion 26 of the skirt wall 10 are raised with rotation. When the top surface wall 8 of the shell 4 and the main portion 26 of the skirt wall 10 are raised over the distance D 2, the upper edge of the inward displacement portion 42 generated in the shell 4 becomes the annular receiving surface 54 of the packing 6. It can be brought into contact. After that, the packing 6 is also raised in association with the elevation of the top wall 8 of the shell 4 and the main portion 26 of the skirt wall 10, so that the packing 6 is separated upward from the mouth-and-neck portion 56 and the mouth-and-neck portion. The sealing of 56 is released, and the packing 6 is detached together with the top surface wall 8 of the shell 4 and the main portion 26 of the skirt wall 10 from the mouth and neck portion 56, and the mouth and neck portion 56 is opened. The packing 6 is separated upward from the mouth-and-neck portion 56 and the sealing of the mouth-and-neck portion 56 is released. The circumferential break line 24 in the shell 4 is broken, and the main wall 8 and the skirt wall 10 of the shell 4 are broken. After the portion 26 has been raised over the distance D2, the sealing of the mouth-and-neck portion 56 is not released prior to the breaking of the circumferential break line 24.

  When only a part of the contents of the container is consumed, the packing 6 held therein together with the top surface wall 8 of the shell 4 and the main portion 26 of the skirt wall 10 separated from the mouth and neck portion is put into the mouth and neck portion. 56, the female thread 74 of the shell 4 is screwed again to the male thread 58 of the mouth-and-neck part 56, and thus the mouth-and-neck part 56 can be temporarily sealed.

  In the embodiment described above, when opening the mouth and neck portion 56, the circumferential break line 24 formed in the skirt wall 10 of the shell 4 is broken throughout the circumferential direction, and the tamper evidence skirt portion 28 is formed. It is completely separated from the main portion 26 of the skirt wall 10, but if desired, one or more axial break lines are disposed at the tamper evidence skirt 28 to open the mouth-and-neck portion 56. The circumferential rupture line is not completely ruptured, but part of it remains, and the axial rupture line is ruptured so that the tamper evidence hem is developed from an endless annular shape to an end band shape. The entire shell 4 including the hem portion can be detached from the mouth-and-neck portion 56.

  FIG. 6 illustrates a modified embodiment of the mounting operation for mounting the container lid 2 on the mouth-and-neck portion 56 of the container and sealing the mouth-and-neck portion 56. In the modified embodiment illustrated in FIG. 6, the pressing tool 164 is configured with two pressing members, that is, a configuration including a central pressing member 165 and an outer pressing member 167. The central pressing member 165 has a flat circular pressing surface 166 and acts on the inner region of the outer annular portion 22 in the shell 4 of the container lid 2 to press the container lid 2 downward. On the other hand, the outer pressing member 167 extends substantially vertically downward, then extends radially outward substantially horizontally, further extends substantially vertically downward, and then extends downward and inclined radially outward. And has a surface 169 that acts on the outer side of the shell 4 of the container lid 2 in the radial direction of the annular ridge 16 so that the shoulder region 14 of the shell 4 (see FIG. 1), ie the peripheral edge of the top wall 8. And the upper edge of the skirt wall 10 is immersed downward and radially inward. The mounting operation illustrated in FIG. 6 is substantially the same as the mounting operation illustrated in FIG. 3 except that a pressing tool 164 composed of a central pressing member 165 and an outer pressing member 167 is used.

  In the mounting operation shown in FIGS. 3 and 6, only the shoulder region 14 of the shell 4 of the container lid is immersed downward and radially inward, but if desired, as indicated by a two-dot chain line in FIG. In addition, a region located radially inward of the annular protrusion 16 in the shell 4 and radially inward from the inner peripheral surface of the upper end of the mouth-and-neck portion 56 can also be immersed somewhat downward.

Next, examples and comparative examples of the present invention will be described.
EXAMPLE A container lid having the form shown in FIG. 1 was produced. The manufactured container lid is a container lid for containers with a nominal diameter of 38 mm for the neck and neck, the shell is formed from an aluminum thin plate with a thickness of 0.25 mm, and the packing is a blend resin of styrene elastomer and polypropylene Formed from. The center diameter of the annular ridge formed on the top wall of the shell was 34.4 mm, and the protrusion amount D1 was 0.5 mm.

  A container sold by Toyo Seikan Co., Ltd. under the trade name “TEC200” (having a mouth-and-neck portion in the form as shown in FIG. 2, having a nominal diameter of 38 mm and a nominal volume of 200 ml, Filled with 190 ml of 90 ° C. water in a chrome sun-treated steel sheet container with a thermoplastic resin coating on both sides), and further supplies nitrogen and water vapor to the remaining space of the container (so-called head space) to replace the air, And the container lid was mounted | worn with the mouth-and-neck part of the container by the mounting | wearing style as illustrated in FIG. 3, and the mouth-and-neck part was sealed. At this time, a force of 1400 N was applied to the mounting tool. The filling amount of water vapor is such that the theoretical reduced pressure value in the container when the water vapor is cooled to room temperature is 35 to 40 kPa.

  Next, the following drop impact resistance test (this drop impact resistance test is an extremely severe test) was performed. A container lid was attached, the container was turned upside down, allowed to freely fall 30 cm through a vertical drop path, and collided with an iron cylindrical member whose upper surface was an inclined surface with an inclination angle of 10 degrees. Then, the mouth and neck of the container was immersed in a solution in which 13.2 g of methyl violet was mixed with 1000 ml of 2-butoxyethanol, and an external pressure of 0.1 MPa was applied for 30 minutes. Subsequently, the mouth and neck of the container was taken out of the solution and dried at room temperature and normal humidity for 24 hours (one day). Thereafter, the container lid was removed from the mouth and neck, the mouth and neck were opened, and the water in the container was observed. The solution is bluish purple, and when the solution is slightly sucked into the container, the water in the container is bluish purple. As a result of performing the drop impact resistance test as described above for 10 container lids, it was confirmed that the water in the containers was colorless for any of the container lids and there was no sealing damage due to the drop impact. .

  Ten of the same container lids as those of the example were manufactured except that no annular ridge was formed on the top wall of the shell, and a drop resistance test similar to that of the example was performed. It was confirmed that the water in the container was bluish purple and the seal was damaged by the drop impact.

The front view which shows a suitable embodiment of the container lid comprised according to this invention in part with sectional drawing. FIG. 2 is a front view partially showing a cross-sectional view of a state in which the container lid of FIG. 1 is fitted on the mouth and neck of the container. The front view which shows one part with sectional drawing the mounting | wearing style which mounts | wears with the container neck of FIG. 1 at the mouth neck part of a container, and seals a mouth neck part. FIG. 4 is an enlarged cross-sectional view showing a part of the mounting style shown in FIG. The front view which shows a state with which the container neck shown in FIG. 1 was mounted | worn to the mouth neck part of the container, and the mouth neck part was sealed, partially in sectional drawing. FIG. 5 is a front view partially showing a sectional view of a modified embodiment of a mounting style in which the container lid of FIG. 1 is mounted on the mouth and neck of the container to seal the mouth and neck.

Explanation of symbols

2: Container lid 4: Shell 6: Packing 8: Shell top wall 10: Shell skirt wall 12: Shell boundary 14: Shell shoulder region 16: Annular ridge 56: Container neck and neck 64: Pressing tool 68: Pressing inclined surface 164: Pressing tool

Claims (9)

A shell made of a thin metal plate and a synthetic resin packing, the shell having a circular top wall and a skirt wall depending from the peripheral edge of the top wall, the packing having a disk shape as a whole, the mouth of the container When attached to the mouth and neck of the container to seal the neck, the shoulder region of the shell from the peripheral edge of the top wall to the upper end of the skirt wall is deformed radially inward and downward. In the container lid of the form,
An inwardly projecting annular ridge is formed on the shoulder region of the shell.   The container lid according to claim 1, wherein the annular ridge is formed at a peripheral edge of the top wall and is opposed to an upper surface of the packing that extends substantially horizontally.   The container lid according to claim 1, wherein a cross-sectional shape of the annular protrusion is an arc shape.   The container lid according to any one of claims 1 to 3, wherein a protruding amount of the annular protrusion is 0.2 to 0.8 mm.   The container lid according to any one of claims 1 to 4, wherein the packing is non-adhered to the shell.   The shoulder region of the shell is deformed by pressing with a tool having a pressing inclined surface inclined at an inclination angle α of 5 to 30 degrees with respect to the horizontal. The container lid according to 1.   The shoulder region of the shell is deformed by pressing with a tool having a pressing surface acting on a radially outer side of the annular ridge in the shoulder region. Container lid. A sealing method in which a container lid is attached to the mouth and neck of a container to seal the mouth and neck, the container lid being composed of a metal sheet shell and a synthetic resin packing, the shell having a circular top wall A skirt wall that hangs down from the peripheral edge of the top wall, and the packing is generally disc-shaped, and the shell lid is fitted on the mouth-and-neck portion, and then the peripheral edge of the top wall in the shell is In the sealing method in which the shoulder region leading to the upper end of the skirt wall is deformed radially inward and downward,
An inwardly projecting annular ridge is formed in the shoulder region of the shell, and a tool having a pressing inclined surface inclined at an inclination angle α of 5 to 30 degrees with respect to the horizontal is used for the shell. A sealing method, wherein the shoulder region is deformed by pressing the shoulder region. A sealing method in which a container lid is attached to the mouth and neck of a container to seal the mouth and neck, the container lid being composed of a metal sheet shell and a synthetic resin packing, the shell having a circular top wall A skirt wall that hangs down from the peripheral edge of the top wall, and the packing is generally disc-shaped, and the shell lid is fitted on the mouth-and-neck portion, and then the peripheral edge of the top wall in the shell is In the sealing method in which the shoulder region leading to the upper end of the skirt wall is deformed radially inward and downward,
An inwardly projecting annular ridge is formed on the peripheral edge of the top wall of the shell, and the shoulder is formed by a tool having a pressing surface that acts on a radially outer side of the annular ridge in the shoulder region. A sealing method, wherein the shoulder region is deformed by pressing the region.

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