JP7303576B2 - packaging container - Google Patents

Description

The present invention relates to packaging containers.

Conventionally, fermented foods such as coffee beans, miso, and kimchi are distributed as packages wrapped with packaging materials. The package in which the fermented food is packaged is provided with a ventilation hole for releasing gas generated from the package to the outside of the package, and a gas vent valve is attached so as to cover the ventilation hole. ing. The vent valve opens when the pressure within the package is increased by gas generated within the package, releasing the gas to the outer region of the package. After the gas is released, the valve is closed to prevent oxygen from flowing into the package from the external region. This suppresses deterioration in the quality of fermented foods.

As such a gas vent valve, for example, Patent Literature 1 discloses a gas vent valve including a main body layer and a frame-shaped adhesive layer laminated on the lower surface side of the main body layer. The adhesive layer includes a peelable adhesive region that can be peeled and re-adhered to the package, and a sticking region configured to have a higher peel strength than the peelable adhesive region. In the gas vent valve of Patent Document 1, the gas vent valve deforms upward when the pressure inside the package exceeds a predetermined pressure, that is, the valve opening pressure. Along with the deformation, the peelable adhesive area moves away from the package, forming an air passage between the peelable adhesive area and the package, thereby opening the valve. Then, when the pressure inside the package falls below the valve opening pressure, the peelable adhesive region is drawn to the portion of the adhesive layer where the adhesive layer has not been peeled (that is, the sticking region) and returns to the position where it contacts the package. The releasable adhesive area is re-adhered to the package and the valve is closed. That is, in the gas vent valve of Patent Document 1, the gas in the package passes between the peelable adhesive region and the package and is released from the side surface of the gas vent valve.

JP 2015-189492 A

By the way, in the package containing fermented foods such as miso and kimchi, it is necessary to prevent the degassing valve from peeling off due to friction and the like, and to further suppress the inflow of oxygen from the external region into the package. Therefore, a cover may be provided to cover the gas vent valve. The gas released from the gas vent valve passes through a small gap between the lid and the package surface and is released to the outer region of the lid.

However, in a packaging container provided with a lid on a packaging body, the packaging body expands as the pressure inside the packaging body rises, and the lid body and the gas vent valve come into close contact with each other, so that the gas vent valve cannot be opened smoothly. Therefore, there is a possibility that the valve opening pressure may increase.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a packaging container capable of reducing the opening pressure of a gas vent valve.

A packaging container according to the present invention is a packaging container for packaging a gas-generating substance, comprising a container body having an opening, and an inner lid attached to cover the opening of the container body and having a ventilation hole formed therein. a gas vent valve attached to the outer surface of the inner lid so as to cover the vent hole formed in the inner lid; and an outer lid fitted to the container body so as to cover the inner lid. a body, wherein the outer lid includes a plurality of embossed portions protruding toward the inner lid, and an outer peripheral portion on an outer periphery of a region overlapping with the gas vent valve when viewed from the projecting direction; A plurality of embossments are disposed on the perimeter.

In the packaging container, a plurality of embossed portions are arranged on the outer peripheral portion of the outer lid, so that the embossed portions function as spacers when the inner lid swells as the pressure inside the container body rises. As a result, close contact between the lid and the gas vent valve can be suppressed, and the valve opening pressure can be reduced.

In the packaging container according to the present invention, on a virtual line connecting the shortest distance from the center position of the ventilation hole formed in the inner lid to the embossed portion when viewed from the projecting direction, from the center position of the ventilation hole to the above-mentioned When the shortest distance to the embossed portion is L ₁ and the distance from the center position of the vent hole to the outer edge of the gas vent valve is L ₂ , the ratio of L ₁ to L ₂ (L ₁ /L ₂ ) is 1. It may exceed 0 and be 2.0 or less.

With such a configuration, the packaging container can further reduce the opening pressure of the degassing valve.

In the packaging container according to the present invention, the plurality of embossed portions may be arranged at equal intervals in the circumferential direction on the outer peripheral portion of the outer lid.

With such a configuration, the packaging container can suppress distortion of the inner lid when the inner lid is inflated due to an increase in pressure inside the container body. As a result, the gas vent valve can be opened more smoothly and the valve opening pressure can be further reduced.

In the packaging container according to the present invention, at least four embossed portions may be arranged.

With such a configuration, the packaging container can further suppress the occurrence of distortion of the inner lid when the inner lid is inflated due to an increase in pressure within the container body. As a result, the gas vent valve can be opened more smoothly and the valve opening pressure can be further reduced.

ADVANTAGE OF THE INVENTION According to this invention, the packaging container which can reduce the valve-opening pressure in a degassing valve can be provided.

FIG. 1 is an end view of a packaging container 1 according to a first embodiment of the invention. FIG. 2 is a partially enlarged view of the packaging container 1 shown in FIG. 1 as viewed from above. 3 is a bottom view of the outer cover 5 shown in FIG. 1. FIG. FIG. 4 is a bottom view of the outer lid 5 of the packaging container 1 according to the second embodiment of the invention. FIG. 5 is a bottom view of the outer lid 5 of the packaging container 1 according to the third embodiment of the invention. FIG. 6 is a bottom view of the outer lid 5 of the packaging container 1 according to the fifth embodiment.

[First embodiment]
A packaging container 1 according to a first embodiment of the present invention will be described below with reference to the drawings. In the drawings below, the same reference numerals are given to the same or corresponding parts, and the description thereof will not be repeated.

1 is an end view of a packaging container 1 according to a first embodiment of the present invention, FIG. 2 is a partially enlarged view of the packaging container 1 shown in FIG. 1 as viewed from above, and FIG. 2 is a bottom view of the outer lid body 5 shown. FIG. As shown in FIG. 1, the packaging container 1 includes a container body 2 having an opening 20, an inner lid 3 attached to cover the opening 20 of the container body 2, and an outer surface of the inner lid 3. and an outer lid body 5 fitted to the container body 2 so as to cover the inner lid body 3 . The outer lid 5 includes a plurality of embossed portions 54 projecting toward the inner lid 3 side. In this specification, the direction in which the embossed portion 54 protrudes (the Z direction in FIG. 1) is referred to as the "protruding direction", and the direction in which the gas vent path is formed in the gas vent valve 4 (the Y direction in FIG. 1). direction) is referred to as the "ventilation direction".

A packaging container 1 is a packaging container for packaging a gas-generating substance. Examples of gas-generating substances include coffee beans, heated coffee, tea beverages such as tea, miso, kimchi, cheese, fermented foods such as sauerkraut, and gas-generating chemical products such as detergents that generate gas. be done.

The container body 2 forms a storage space for storing the gas-generating substance, and is provided with an opening 20 that opens the storage space upward. Specifically, the container body 2 includes a housing portion 21 that forms a housing space and has an opening 20, and a flange portion that extends outward from the container body 2 from the end portion of the housing portion 21 that forms the opening 20. 22. That is, the flange portion 22 is annularly formed so as to surround the opening 20 of the container body 2 when viewed from the projecting direction.

The container body 2 is made of a material containing resin, and can be molded into a container shape.

The inner lid body 3 has a vent hole 31 passing through the inner lid body 3 . Specifically, the inner cover 3 is provided with a circular ventilation hole 31 at the center of the inner cover 3 , through which the gas in the container body 2 is released. Further, the inner lid 3 is attached so as to cover the opening 20 of the container body 2 . Specifically, when the inner lid 3 is put over the opening 20 of the container body 2 from above, the flange portion 22 of the container body 2 and the outer peripheral end portion 30 of the inner lid 3 overlap. Then, the inner lid body 3 is attached to the container body 2 by fixing the overlapped portion of the flange portion 22 and the outer peripheral end portion 30 with an adhesive or the like.

The inner lid body 3 is formed of a deformable film, and for example, a non-adhesive flexible resin film can be used. Examples of non-adhesive flexible resin films include resin films made of polyethylene terephthalate, polyolefin, and the like.

The gas vent valve 4 includes a main body layer 41 and a frame-shaped adhesive layer 42 laminated on the lower surface side of the main body layer 41 (bottom side in the Z direction in FIG. 1). The gas vent valve 4 is attached to the inner lid body 3 so that the frame-shaped adhesive layer 42 surrounds the ventilation hole 31 of the inner lid body 3 (that is, so that the ventilation hole 31 fits within the frame of the frame-shaped adhesive layer 42). be pasted on. As a result, an internal space R is formed and the container body 2 is hermetically sealed. The gas vent valve 4 allows gas to be released from the inside of the container body 2 to the outside region when the pressure inside the container body 2 (hereinafter also referred to as internal pressure) becomes higher than the valve opening pressure.

Specifically, when the internal pressure in the container body 2 becomes higher than the atmospheric pressure in the external region, pressure is applied to the gas vent valve 4 and the inner lid 3, and the gas vent valve 4 (specifically, the body layer 41) is closed. It deforms upward (the Z direction in FIG. 1). Along with the deformation, the peelable adhesive area 42a described later is lifted upward and peeled off, thereby forming an air passage between the peelable adhesive area 42a and the inner lid body 3. As shown in FIG. By forming the air passage, the inside of the container main body 2 and the external region are in an open state in which the valve is in communication. Even in the valve open state, since the later-described sticking area 42b does not peel off from the inner lid 3, the state where the gas vent valve 4 is stuck to the inner lid 3 can be maintained.

In the open state, the gas inside the container body 2 is released to the outside area. When the internal pressure in the container body 2 falls below a predetermined pressure, that is, the valve opening pressure in the valve open state, the peeled adhesive region 42a is attracted to the portion of the adhesive layer 42 that is not peeled (that is, the stuck region 42b), and the inner lid is closed. It returns to the position in contact with the body 3, and the peeled-off adhesion area 42a again adheres to the inner cover 3, and the valve is closed. In the closed state, the gas inside the container body 2 is not released to the outside region, and oxygen is prevented from flowing into the container body 2 from the outside region.

It is preferable that the valve opening pressure is a pressure exceeding the atmospheric pressure and not more than the bursting strength of the packaging material (JIS-P-8112 Mullen method). In order for the gas vent valve 4 to open at a slight pressure, such as the pressure of the gas generated from the gas generating material, it is preferable to set the valve opening pressure to a pressure close to the atmospheric pressure. Specifically, the valve opening pressure is preferably 1.0 kgf/cm ² or more and 2.0 kgf/cm ² or less, more preferably 1.0 kgf/cm ² or more and 1.5 kgf/cm ² or less. .

The body layer 41 is formed in a square shape when viewed from above. Further, the main body layer 41 is made of a deformable film so as to follow the deformation of the inner cover 3 . As the body layer 41, for example, a non-adhesive flexible resin film can be used. Examples of non-adhesive flexible resin films include resin films made of polyethylene terephthalate, polyolefin, and the like. The thickness of the main body layer 41 is preferably 12 μm or more and 200 μm or less, more preferably 16 μm or more and 75 μm or less.

As shown in FIG. 2, the adhesive layer 42 is formed in the same rectangular frame shape as the main body layer 41 when viewed from above. In addition, when viewed from above, the outer peripheral edge of the adhesive layer 42 and the outer peripheral edge of the main body layer 41 overlap each other. That is, the gas vent valve 4 as a whole is formed in a square shape when viewed from above, and the outer peripheral edge of the gas vent valve 4 includes four corner portions 4a and four side portions 4b connecting the corner portions 4a. consists of

The adhesive layer 42 includes a peelable adhesive region 42a that can be peeled off and re-adhered to the inner cover 3, and a sticking region 42b configured to have a higher peel strength than the peelable adhesive region 42a. The attachment regions 42b are located at both ends of the adhesive layer 42 in a direction perpendicular to the ventilation direction (the X direction in FIG. 2). The peelable adhesive regions 42a are located at both ends of the adhesive layer 42 in the ventilation direction and in regions other than the sticking regions 42b. In addition, in this specification, orthogonal means orthogonal with consideration given to tolerance.

The peelable adhesive region 42a is formed of, for example, a self-adsorbing UV-curable resin or the like, and from the viewpoint of reducing the valve opening pressure, it is preferably formed of a UV-curable resin that can control the self-adsorbing force. Such UV curable resins include, for example, silicone-based monomers/oligomers having acrylate groups, long-chain alkyl-based monomers/oligomers having acrylate groups, or mixtures of these monomers/oligomers and thermoplastic polymers. etc. The thickness of the peelable adhesive region 42a is preferably 0.1 μm or more and 50 μm or less, and more preferably 1 μm or more and 30 μm or less.

The peel strength of the peelable adhesive region 42a with respect to the inner lid 3 is appropriately determined according to the material of the inner lid 3, and is not particularly limited. It is preferably 0.4 N/m or more and 28 N/m or less. By setting the peel strength within the above range, sufficient adhesion to the inner lid 3 and good peelability can be ensured. In addition, in this specification, peel strength can be measured by the 90-degree peel test method based on JISK6854.

The sticking area 42b is formed using an adhesive that has a higher peel strength with respect to the inner lid body 3 than the resin used for the peelable adhesive area 42a. As a result, when the valve is opened, an air passage is formed between the peeling adhesive region 42a and the inner lid 3 without forming an unintended air passage between the sticking region 42b and the inner lid 3. can be done. The sticking region 42b is made of, for example, a layer made of a known adhesive such as a rubber-based adhesive, an acrylic adhesive, a silicone-based adhesive, an EVA-based emulsion adhesive, a synthetic rubber-based adhesive, a cyanoacrylate-based adhesive, or the like. known adhesives. The thickness of the attachment region 42b is not particularly limited, and is preferably 10 μm or more and 50 μm or less, and more preferably 15 μm or more and 25 μm or less.

The peel strength of the sticking region 42b to the inner lid body 3 is not particularly limited as long as the peel strength is higher than the resin forming the peel adhesive region 42a, and is, for example, 200 N/m or more and 1200 N/m or less. 400 N/m or more and 800 N/m or less is more preferable.

As shown in FIG. 3, the outer lid 5 includes an outer lid main body portion 51 and a fitting portion 52 formed so as to surround the outer lid main body portion 51 when viewed from the projecting direction. Moreover, as shown in FIG. 2, the outer cover 5 has an outer peripheral portion 53 on the outer periphery of the region overlapping the gas vent valve 4 when viewed from the projecting direction. The fitting portion 52 fits with the flange portion 22 of the container body 2 . As a result, the outer lid 5 is attached to the container body 2 .

As shown in FIG. 1, the outer lid 5 includes a plurality of embossed portions 54 projecting toward the inner lid 3 side. As shown in FIG. 3, the embossed portion 54 is formed in a circular shape when viewed from the projecting direction. The diameter of the embossed portion viewed from the direction of projection is preferably 1 mm or more and 3 mm or less, more preferably 1 mm or more and 1.5 mm or less. The length of the embossed portion 54 along the protruding direction is preferably 0.5 mm or more and 2.0 mm or less, and more preferably 0.5 mm or more and 1.5 mm or less. In addition, the embossed portion 54 is formed by a conventionally known method such as a embossing method.

The embossed portion 54 is formed on the outer peripheral portion 53 on the inner surface of the outer lid 5 . Eight embossed portions 54 are arranged at the apexes of the octagonal shape at even intervals in the circumferential direction on the outer peripheral portion 53 on the inner surface of the outer cover 5 when viewed from the projecting direction. By arranging the embossed portion 54 in this way, the gas vent valve 4 can be opened more smoothly, the valve opening pressure can be further reduced, and the sealing property from the external region of the packaging container 1 can be improved. In addition, it is possible to prevent the gas-generating substance in the container body 2 from scattering to the outside area.

The embossed portions 54 include a corner embossed portion 54a arranged at a position corresponding to the corner 4a of the gas vent valve 4, and a side embossed portion 54b arranged at a position corresponding to the side portion 4b of the gas vent valve 4. consists of More specifically, the corner embossed portion 54a is arranged on an extension line of an imaginary line connecting the corner 4a of the gas vent valve 4 from the center position of the vent hole 31 at the longest distance, and the side embossed portion 54b is located on the vent hole 31. is arranged on the extension line of the imaginary line connecting the side portion 4b of the gas vent valve 4 from the center position of the gas vent valve 4 at the shortest distance. The corner embossed portions 54a and the side embossed portions 54b are alternately arranged along the circumferential direction.

As shown in FIG. 2, on the virtual line M connecting the shortest distance from the center position of the ventilation hole 31 formed in the inner lid body 3 to the embossed portion 54 when viewed from the projecting direction, from the center position of the ventilation hole 31 When the shortest distance to the embossed portion 54 is L ₁ and the distance from the center position of the vent hole 31 to the outer edge of the gas vent valve 4 is L ₂ , the ratio of L ₁ to L ₂ (L ₁ /L ₂ ) is 1. It is preferably more than 0.0 and 2.0 or less, and preferably 1.3 or more and 1.7 or less. The shortest distance _L1 can be, for example, 14.0 mm or more and 23.0 mm or less. Also, the distance _L2 can be, for example, 7.0 mm or more and 20.0 mm or less. In addition, in the first embodiment, the shortest distance _L1 in each embossed portion 54 is all formed equally. In addition, when the embossed portion 54 is the corner embossed portion 54a, the distance _L2 in each embossed portion 54 is the longest distance connecting the corner 4a of the gas vent valve 4 from the center position of the vent hole 31, and the embossed portion When 54 is the embossed side portion 54b, it is the shortest distance from the center position of the vent hole 31 to the side portion 4b of the gas vent valve 4. As shown in FIG.

In the packaging container 1 according to this embodiment, a plurality of embossed portions 54 are arranged on the outer peripheral portion 53 of the outer lid 5, so that when the inner lid 3 expands due to the pressure increase in the container body 2, the embossed portions 54 functions as a spacer. As a result, the tight contact between the inner cover 3 and the gas vent valve 4 can be suppressed, and the valve opening pressure can be reduced.

In the packaging container 1 according to the present embodiment, the shortest distance from the center position of the ventilation hole 31 formed in the inner lid body 3 to the embossed portion 54 when viewed from the projecting direction is on the imaginary line M. _The ratio of _L1 to _{L2 ( L1} / _L2 ) exceeds 1.0 and is 2.0 or less, the opening pressure of the gas vent valve 4 can be further reduced.

In the packaging container 1 according to the present embodiment, the plurality of embossed portions 54 are arranged on the outer peripheral portion 53 of the outer lid body 5 at even intervals in the circumferential direction, so that the pressure inside the container body 2 increases as the pressure inside the container body 2 increases. When the lid body 3 is inflated, the inner lid body 3 can be prevented from being distorted. As a result, the gas vent valve 4 can be opened more smoothly and the valve opening pressure can be further reduced.

In the packaging container 1 according to the present embodiment, eight embossed portions 54 are arranged to suppress the occurrence of distortion of the inner lid 3 when the inner lid 3 expands due to an increase in pressure inside the container body 2. can do. As a result, the gas vent valve 4 can be opened more smoothly and the valve opening pressure can be further reduced.

[Second embodiment]
A packaging container 1 according to a second embodiment of the present invention will be described below with reference to the drawings for portions that differ from the first embodiment. In the drawings below, the same reference numerals are given to the same or corresponding parts, and the description thereof will not be repeated.

FIG. 4 is a bottom view of the outer lid 5 of the packaging container 1 according to the second embodiment of the invention. As shown in FIG. 4, four embossed portions 54 are arranged at the vertices of a quadrangular shape at even intervals in the circumferential direction on the outer peripheral portion 53 on the inner surface of the outer lid 5 when viewed from the projecting direction. ing.

In the packaging container 1 according to the second embodiment of the present invention, four embossed portions 54 are arranged at equal intervals in the circumferential direction on the outer peripheral portion 53 of the outer lid body 5, thereby making the gas vent valve 4 more effective. The valve can be opened smoothly to further reduce the valve opening pressure, and the sealing property from the outer region of the packaging container 1 can be improved, and the scattering of gas-generating substances in the container body 2 to the outer region can be prevented. can do.

[Third embodiment]
A packaging container 1 according to a third embodiment of the present invention will be described below with reference to the drawings for portions that differ from the first embodiment. In the drawings below, the same reference numerals are given to the same or corresponding parts, and the description thereof will not be repeated.

FIG. 5 is a bottom view of the outer lid 5 of the packaging container 1 according to the third embodiment of the invention. As shown in FIG. 5, two embossed portions 54 are arranged along the ventilation direction at equal intervals in the circumferential direction on the outer peripheral portion 53 on the inner surface of the outer lid 5 when viewed from the projecting direction.

In the packaging container 1 according to the third embodiment of the present invention, the embossed portions 54 are arranged at equal intervals in the circumferential direction on the outer peripheral portion 53 of the outer lid 5, so that the gas vent valve 4 can be operated more smoothly. By opening the valve, the valve opening pressure can be further reduced.

[Other embodiments]
The first to third embodiments of the present invention (hereinafter collectively referred to as the present embodiment) have been described above, but the present invention is not limited to the present embodiment. Various modifications can be made without departing from the gist of the invention.

In the packaging container 1 according to this embodiment, the shape of the embossed portion 54 is circular when viewed from the projecting direction. However, the present invention is not limited to this configuration, and may be polygonal or the like.

In the packaging container 1 according to this embodiment, the embossed portions 54 are arranged at equal intervals in the circumferential direction on the outer peripheral portion 53 of the outer lid 5 . However, the present invention is not limited to this configuration, and the embossed portions 54 may not be arranged at equal intervals.

Although two, four, and eight embossed portions 54 are arranged in the packaging container 1 according to the present embodiment, the present invention is not limited to this configuration. At least four embossed portions 54 are preferably arranged from the viewpoint of opening the gas vent valve 4 more smoothly and further reducing the valve opening pressure.

In the packaging container 1 according to this embodiment, a ventilation hole 31 is formed in the center of the inner lid 3 . Also, the vent hole 31 is formed in a circular shape. However, the present invention is not limited to this configuration, and the vent hole 31 may be formed in an area biased toward the side edge side of the inner cover 3 . Moreover, the vent hole 31 may be formed in an elliptical shape other than a circular shape, a polygonal shape, or the like.

In the packaging container 1 according to this embodiment, the body layer 41 and the adhesive layer 42 of the gas vent valve 4 are formed in a square shape when viewed from above. However, the present invention is not limited to this configuration, and the body layer 41 and the adhesive layer 42 may be formed in a polygonal shape, a circular shape, or the like.

In the packaging container 1 according to the present embodiment, the sticking regions 42b of the gas vent valve 4 are located at both ends of the adhesive layer 42 in the direction perpendicular to the ventilation direction (the X direction in FIG. 2), and the peeling adhesive regions 42a , at both ends of the adhesive layer 42 in the ventilation direction and in areas other than the attachment area 42b. However, the present invention is not limited to this configuration, and the arrangement of the sticking area 42b and the peelable adhesive area 42a can be changed as appropriate. For example, the peelable adhesive area 42a may be arranged only at one end of the adhesive layer 42 in the ventilation direction, or the adhesive area 42b may be arranged so as to be positioned at a corner of a rectangular frame, and the peelable adhesive area You may arrange|position 42a in four places so that it may be located between the said corner|angular parts.

In the packaging container 1 according to the present embodiment, the peeling adhesive region 42a is continuously formed in a predetermined region in the gas vent valve 4 and is formed in the shape of one flat plate. However, the present invention is not limited to this configuration, and the peel adhesive regions 42a may be intermittently formed in predetermined regions. Specifically, the peel adhesive region 42a may be formed from a plurality of ridges that are spaced apart from each other.

In the packaging container 1 according to the present embodiment, an air passage is formed between the adhesive layer 42 (peeling adhesive area 42 a ) and the inner cover 3 in the gas vent valve 4 . However, the present invention is not limited to this configuration, and an additional layer constituting the gas vent valve 4 may be provided to form an air passage between the layers of the laminated structure. For example, by arranging a layer corresponding to the peeling adhesive region 42a between the main body layer 41 and the adhesive layer 42 (in this case, the adhesive layer 42 is composed only of the sticking region 42b), the body layer 41 and the peeling adhesive A ventilation path may be formed between the layer corresponding to the region 42a. Further, for example, two layers corresponding to the peelable adhesive regions 42a having the above configuration are arranged in a superimposed manner. An air passage may be formed between the layers corresponding to the peelable adhesive regions 42a by stacking a separate adhesive layer.

In the packaging container 1 according to the present embodiment, an air passage is formed between the adhesive layer 42 (peeling adhesive area 42 a ) and the inner cover 3 in the gas vent valve 4 . However, the present invention is not limited to this configuration, and the gas vent valve 4 is formed with, for example, a slit penetrating the gas vent valve 4, through which the gas in the container body 2 is discharged to the outside area. Such a configuration may be used. In this case, for example, the frame-shaped adhesive layer 42 is composed only of the sticking region 42b, and a layer corresponding to the peeling adhesive region 42a can be arranged in the region inside the sticking region 42b (that is, the region within the frame). can.

Examples of the present invention will be described below, but the present invention is not limited to the following examples.

<Production of gas vent valve>
The gas vent valves of each example and comparative example were produced by laminating a body layer and an adhesive layer so as to have the same structure as the gas vent valves shown in FIGS. 1 and 2 . Specifically, a resin film made of polyethylene terephthalate (thickness: 25 μm) as the main body layer, X-62-7205 (manufactured by Shin-Etsu Chemical Co., Ltd., thickness: 10 μm) as the peeling adhesive region of the adhesive layer, and the sticking region of the adhesive layer It was produced using an acrylic pressure-sensitive adhesive (thickness: 20 μm) as the base. The gas vent valve had a square shape of 21 mm×21 mm when viewed from the projecting direction, and the size of the internal space serving as the ventilation path and the peeling adhesive area was 21 mm×14 mm.

<Production of packaging container>
(Example 1)
In Example 1, a packaging container according to the first embodiment having the structure shown in FIGS. 1 to 3 was produced. Specifically, as the container main body, a container having a size of 105 mm×105 mm and a height of 85 mm was used as the opening formed by the inner end of the flange. A polyethylene terephthalate film having a size of 120 mm×120 mm and a thickness of 0.205 mm was used for the inner cover. A vent hole with a diameter of 2.0 mm was formed in the center of the inner cover. The vent valve was attached to the inner lid so that the interior space was located above the vent. As the outer lid, a lid formed so as to be fittable with the container body was used. Eight embossed portions were arranged on the outer peripheral portion of the inner surface of the outer cover at the positions corresponding to the apexes of the octagonal shape at equal intervals in the circumferential direction when viewed from the projecting direction. Specifically, four corner embossed portions located corresponding to the corners of the gas vent valve and four side embossed portions located corresponding to the side portions of the gas vent valve were arranged. The embossed portion was produced by adhering a 1.5 mm square rubber sheet with a thickness of 1 mm using a double-sided tape.

(Example 2)
In Example 2, a packaging container according to the second embodiment having an outer lid having the structure shown in FIG. 4 was produced. Specifically, it was produced in the same manner as in Example 1, except that four embossed portions were arranged at equal intervals in the circumferential direction at positions corresponding to the vertices of the quadrangular shape.

(Example 3)
In Example 3, a packaging container according to the third embodiment having an outer cover body having the structure shown in FIG. 5 was produced. Specifically, it was produced in the same manner as in Example 1, except that two embossed portions were arranged along the ventilation direction at equal intervals in the circumferential direction.

(Example 4)
In Example 4, a packaging container was produced in the same manner as in Example 1 except that the embossed portion in the third embodiment was rotated by 90° in the circumferential direction and arranged along the direction perpendicular to the ventilation direction.

(Example 5)
In Example 5, a packaging container having an outer lid having the structure shown in FIG. 5 was produced. Specifically, by setting the embossed portion in Example 2 as the midpoint of each side of the quadrangular shape and further arranging four embossed portions at the vertices of the quadrangular shape, a total of eight embossed portions are formed. placed. In Example 5, a packaging container was produced in the same manner as in Example 2, except that the embossed portions were arranged as described above.

(Comparative example 1)
In Comparative Example 1, a packaging container was produced in the same manner as in Example 1, except that an outer lid body without an embossed portion was used.

<Measurement of opening pressure>
For the packaging container of each example and comparative example, an introduction hole for introducing gas was provided on the side surface of the container body, and the gas was introduced into the container body at a flow rate of 10 mL / min from the introduction hole, thereby degassing. The valve opening pressure (kPa) was measured. The opening pressure was measured three times, and the average value was taken as the average opening pressure.

As can be seen from the results in Table 1, the packaging container of each example that satisfies all the constituent requirements of the present invention can lower the opening pressure of the gas vent valve compared to the packaging container of Comparative Example 1.

REFERENCE SIGNS LIST 1 packaging container 2 container body 3 inner lid 4 gas vent valve 5 outer lid 31 vent hole 41 body layer 42 adhesive layer 42a peel adhesive area 42b pasting area 53 outer peripheral portion 54 embossed portion

Claims (4)

A packaging container for fermented food for packaging a gas-generating substance,
a container body having an opening and formed into a container shape ;
an inner lid attached to cover the opening of the container body and formed with a vent;
a gas vent valve attached to the outer surface of the inner lid so as to cover the vent hole formed in the inner lid;
an outer lid body fitted with the container body so as to cover the inner lid body,
The inner lid body is formed of a deformable film,
The outer lid is
A plurality of embossed portions protruding toward the inner lid body side,
A packaging container comprising an outer peripheral portion on an outer periphery of a region overlapping with the gas vent valve when viewed from a projecting direction, and wherein the plurality of embossed portions are arranged on the outer peripheral portion. L is the shortest distance from the center position of the ventilation hole to the embossed part on the imaginary line connecting the shortest distance from the center position of the ventilation hole formed in the inner cover body to the embossed part when viewed from the projecting direction. _1. When the distance from the center position of the vent hole to the outer edge of the gas vent valve is _L2 , the ratio of _L1 to _L2 ( _L1 / _L2 ) is more than 1.0 and 2.0 or less. The packaging container according to claim 1, which is The packaging container according to claim 1 or 2, wherein the plurality of embossed portions are arranged at equal intervals in the circumferential direction on the outer peripheral portion of the outer cover. The packaging container according to any one of claims 1 to 3, wherein at least four embossed portions are arranged.

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