JP5946415B2 - Automatic ventilation packaging bag and automatic ventilation packaging bag storage box - Google Patents

Description

  The present invention relates to an automatic ventilation packaging bag and an automatic ventilation packaging bag storage box, and more particularly, an automatic ventilation packaging that prevents the packaging bag from bursting by automatically exhausting water vapor generated from the contents when the contents are heated together with the packaging bags. Regarding bags. In addition, the present invention relates to an automatic ventilation packaging bag storage box that can accommodate the automatic ventilation packaging bag and adapt to the volume change thereof.

  In recent years, cooked or partially cooked processed foods have been widely used and distributed for the purpose of preparing meals and simplifying the provision of dishes. In particular, demand is growing more than ever due to a demand for fewer people per household and a reduction in cooking expenses at restaurants. Such cooked food is provided by being enclosed in containers, packaging bags and the like made of various resin films for convenience of distribution. The cooking of cooked food is roughly divided into hot pots such as pans and a microwave oven (high frequency range), and final cooking is often performed. In particular, microwave heating is often preferred from the viewpoint of shortening the heating time and simplifying the work. Therefore, the heat resistance and pressure resistance of the resin film container for food packaging have been enhanced to cope with microwave heating. When heating using a microwave oven, a container expand | swells with the water vapor | steam which arises with evaporation from the contents, such as a foodstuff. However, there is a limit to the expansion of the container. In containers and packaging bags, when the internal pressure reaches a certain limit, the container (packaging bag) bursts and is very dangerous. At the same time, the inside of the microwave is soiled.

  Conventionally, in order to prevent rupture due to water vapor, a user has to open a hole in a container (packaging bag) before heating, which is troublesome. In addition, although there are containers (packaging bags) provided with holes in advance, the airtightness of the containers themselves is not good and is mainly limited to packaging of frozen foods and the like. Therefore, a packaging bag having an automatic ventilation part in a part of the container and the packaging bag has been proposed in order to improve the airtightness of the container itself and to ensure a water vapor escape path in advance. Although the automatic vent is always closed, it is first opened in response to the expansion pressure of water vapor generated from the contents during heating. The filled water vapor is discharged to the outside of the packaging bag and plays the role of a safety valve that lowers the pressure in the container.

  Adjustment of the ease of opening in an automatic ventilation part is implement | achieved by using easy peel resin (easy open resin). That is, it is a packaging bag in which an easy-peeling resin film is interposed in advance in an automatic ventilation portion and heat-sealed (see, for example, Patent Document 1). However, a functional film such as an easy peel resin is expensive and increases the unit price of the packaging bag itself even if the amount used is reduced. In addition, the manufacturing itself is not easy because the heat sealing process needs to be changed. Therefore, the inventor has previously developed a packaging bag that does not use an easy peel resin (see Patent Document 2). However, according to Patent Document 2, the problem of complicated heat sealing conditions and shape near the automatic ventilation section is included. For this reason, the automatic ventilation part still often depends on the use of an easy peel resin.

  According to the packaging bag provided with the conventional automatic ventilation part, the automatic ventilation part has many structures arrange | positioned in the upper and lower sides of the bag main body. For this reason, the automatic ventilation portion is blocked by the way the packaging bag is placed in the microwave oven, and has a serious problem in exhausting water vapor. Therefore, a warning about the top and bottom of the bag was displayed on the packaging bag itself. However, it has not eradicated the rupture of packaging bags resulting from careless placement errors.

  The inventor has tried to improve the structure of the packaging bag and the automatic ventilation part, which has no restrictions on the way of placing the packaging bag, with respect to the problems caused by the above-described placing (see Patent Documents 2, 3, and 4). According to Patent Documents 2 to 4, the automatic ventilation portion is always arranged at an intermediate position of the packaging bag by making the vicinity of the automatic ventilation portion have a W-shaped folding structure in cross section. That is, it is a structure that does not matter whether the packaging bag is upper or lower, and water vapor is surely exhausted from the automatic ventilation portion located in the middle of the packaging bag regardless of which side of the packaging bag is down. As described above, the automatic ventilation portion provided in the folding structure has a certain effect in terms of safety of the packaging bag. On top of that, intensive studies have been made to further improve the manner of expansion of the packaging bag and the steam exhaust after the expansion of the packaging bag.

JP 2007-204072 A JP 2008-24362 A JP 2006-199373 A JP 2009-83914 A

  The present invention has been made in view of the above points, and can discharge water vapor without providing upper and lower restrictions on how to place the packaging bag itself, and also suppress blowout of contents other than water vapor. In addition, the present invention provides an automatic ventilation packaging bag including an automatic ventilation portion configured without using an easy-peeling resin. In addition, there is provided an automatic ventilation packaging bag storage box that is suitable for packaging of the automatic ventilation packaging bag and can easily cope with expansion deformation.

That is, the invention of claim 1 comprises a film body, comprises a bag bottom part and an opening part to constitute a bag-like main body, and an intermediate part provided with an automatic ventilation part between the upper surface part and the lower surface part of the bag-like main body. A first side portion on the upper surface portion and a sixth side portion on the lower surface portion, and a second side portion between the first side portion and the sixth side portion, A third side, a fourth side, and a fifth side are provided in this order, and the intermediate part is a cross-sectional view of the second side, the third side, the fourth side, and the fifth side. Folded into a W shape and formed so that the third side and the fourth side protrude from the center of the bag-like body toward the bag bottom, and each side of the upper surface and the lower surface It is a packaging bag in which heat seal surfaces of side portions are heat sealed to form side heat seal portions, and the automatic ventilation portion An intermediate heat seal portion in which the third side portion and the fourth side portion are heat-sealed in a band shape in the lateral direction of the bag-like main body, and the intermediate heat seal portion disposed at a lateral center position of the intermediate heat seal portion And the third side part and the second side part of the intermediate heat seal part are narrower than the heat seal width of the intermediate heat seal part and protruded in an arc shape toward the center of the bag-like body from the intermediate heat seal part. The intermediate heat seal part and the air vent by folding the third side part and the fourth side part shorter than the heat seal length in the lateral direction of the intermediate heat seal part. A pocket having a cylindrical portion connected to the planned portion and formed in parallel with the intermediate heat seal portion, and an exhaust portion for exhausting the water vapor that has passed through the planned ventilation portion to both ends of the cylindrical portion. And a heat-sealed upper portion of the first side portion and the second side portion projecting from the bag bottom side of the bag-like main body toward the center side of the bag-like main body. The heat seal part and the lower heat which heat-sealed by projecting the horizontal center part of the said 5th side part and the said 6th side part from the bag bottom part side of the said bag-shaped main body toward the center part side of this bag-shaped main body. A seal portion is provided , and an upper inclined heat seal portion that is heat-sealed in an inclined manner from the upper heat seal end on both the left and right sides of the upper heat seal portion to the side heat seal portion is provided, and the lower heat seal A lower inclined heat seal portion is provided that is heat-sealed in an inclined manner from the lower heat seal end portions on both the left and right sides of the seal portion in the lateral direction to the side heat seal portion. The present invention relates to an automatic ventilated packaging bag which is placed in a child cooker and heated for the packaging bag.

The invention of claim 2 comprises a film body, comprises a bag bottom part and an opening part to constitute a bag-like main body, and an intermediate part provided with an automatic ventilation part between the upper surface part and the lower surface part of the bag-like main body. A first side part on the upper surface part and a sixth side part on the lower surface part, and a second side part and a third side part between the first side part and the sixth side part. A side part, a fourth side part, and a fifth side part are provided in this order, and the intermediate part is a W-shaped cross-sectional view of the second side part, the third side part, the fourth side part, and the fifth side part. Folding into a shape, the third side and the fourth side are formed in a direction projecting from the center of the bag-shaped body toward the bag bottom, and each side of the upper surface and the lower surface The heat-sealing surfaces of the packaging bag are side-sealed heat-sealed portions, wherein the automatic ventilation portion is the third side of the intermediate portion. And an intermediate heat seal portion heat-sealed in a band shape in the lateral direction of the bag-shaped main body, and the intermediate heat seal portion arranged at the central position in the lateral direction of the intermediate heat seal portion, The third side part and the fourth side part are heated by projecting in an arc shape toward the center part side of the bag-like body from the intermediate heat seal part and narrower than the heat seal width of the intermediate heat seal part. The sealed ventilation plan part and the intermediate heat seal part and the ventilation plan part are connected by folding the third side part and the fourth side part shorter than the transverse heat seal length of the intermediate heat seal part. A cylindrical portion formed in parallel with the intermediate heat seal portion, and a pocket portion having an exhaust portion for exhausting water vapor that has passed through the vented portion to the outside at both ends of the cylindrical portion. An upper heat seal part that heat-seals the first side part and the second side part in a lateral direction projecting from the bag bottom side of the bag-like body toward the center side of the bag-like body; A lower heat seal portion that is heat-sealed by projecting a lateral central portion of the fifth side portion and the sixth side portion from a bag bottom side of the bag-like body toward the center side of the bag-like body. An upper inclined heat seal portion that is heat-sealed in an inclined manner from the upper heat seal end portions on the left and right sides of the upper heat seal portion in the lateral direction to the side heat seal portion is provided, A lower inclined heat seal part that is heat-sealed in an inclined shape from the lower heat seal end part on the left and right sides of the direction to the side heat seal part is provided, and the upper heat seal end part is formed as a narrow part The heat seal amount of the narrow portion of the upper heat seal end is formed smaller than the heat seal amount of the central portion of the upper heat seal portion, and the lower heat seal end portion is formed as a narrow portion. In addition, the heat seal amount of the narrow portion of the lower heat seal end is formed smaller than the heat seal amount of the central portion of the lower heat seal portion, and the packaging bag is laid down in the microwave oven. It is related with the automatic ventilation packaging bag characterized by being heated to the packaging bag .

The invention according to claim 3 relates to the automatic ventilated packaging bag according to claim 1 or 2 , wherein the belt-like heat seal width of the intermediate heat seal portion decreases from the side portion side toward the vented portion.

The invention according to claim 4 relates to the automatic ventilated packaging bag according to any one of claims 1 to 3 , wherein an incompletely sealed portion formed by heat sealing the exhaust portion is provided.

According to a fifth aspect of the present invention, the heat sealing surfaces of the film bodies of the first side portion and the sixth side portion are heat sealed in the vicinity of both end portions in the lateral direction of the intermediate heat seal portion. 4. The automatic ventilation packaging bag according to any one of 4 above.

  According to a sixth aspect of the present invention, there is provided the automatic ventilated packaging bag according to any one of the first to fifth aspects, wherein the upper surface portion, the lower surface portion, and the intermediate portion are formed by bending a single film body. Related.

  The invention of claim 7 is a rectangular parallelepiped storage box for storing the automatic ventilation packaging bag according to any one of claims 1 to 6, wherein the box openings of the storage box are provided to face each other. One of the box opening portions is sealed by an easy opening portion and the other is sealed by a fixed sealing portion, and the easy opening portion has a concave shape in a plan view provided with a receding portion at the center in the lateral direction of the easy opening portion. An arcuate edge having a convex shape in plan view is provided with a concave edge extending to the lower surface of the box, and an arcuate bulging part that enters the receding part is provided at the center in the width direction of the easy-opening part. The automatic ventilation packaging bag storage box is provided to extend to an upper surface portion, and the automatic ventilation packaging bag is arranged and accommodated on the easy-opening portion side.

  The invention of claim 8 is provided with a lower surface easily bent portion extending from the start point of the retracted portion to the lower surface portion of the box and an upper surface easily bent portion extending from the start point of the bulging portion. The automatic ventilation packaging bag storage box according to claim 7.

  The invention of claim 9 relates to the automatic ventilated packaging bag storage box according to claim 7 or 8, wherein a box self-supporting leg portion is provided in either or both of the fixed sealing portion and the easy-opening portion.

According to the automatic ventilation packaging bag of the invention of claim 1, the bag body is formed of a film body and includes a bag bottom portion and an opening portion, and automatic ventilation is performed between the upper surface portion and the lower surface portion of the bag-shaped main body. An intermediate portion is provided, and in the bag bottom portion, a first side portion is provided on the upper surface portion, and a sixth side portion is provided on the lower surface portion, and between the first side portion and the sixth side portion. The second side, the third side, the fourth side, and the fifth side are provided in this order, and the intermediate portion includes the second side, the third side, the fourth side, and the fifth side. Folding side portions into a W-shaped cross-sectional view and forming the third side portion and the fourth side portion in a direction projecting from the center portion of the bag-like body toward the bag bottom side, the upper surface portion and the lower surface A heat-sealing part of each side part of the part is heat-sealed to form a side heat-seal part, wherein the automatic ventilation part An intermediate heat seal portion in which the third side portion and the fourth side portion of the intermediate portion are heat-sealed in a band shape in the lateral direction of the bag-shaped main body, and a central position in the lateral direction of the intermediate heat seal portion. The third heat seal portion is connected to the intermediate heat seal portion, and is narrower than the heat seal width of the intermediate heat seal portion, and protrudes in an arc shape toward the center portion side of the bag-like body from the intermediate heat seal portion. The intermediate heat is obtained by folding the third side part and the fourth side part shorter than the horizontal heat seal length of the intermediate heat seal part. A cylindrical portion connected to the seal portion and the planned ventilation portion and formed in parallel with the intermediate heat seal portion, and an exhaust portion for exhausting water vapor that has passed through the planned ventilation portion to both ends of the cylindrical portion to the outside And a pocket portion having the first side portion and the second side portion in the lateral direction projecting from the bag bottom portion side of the bag-like body toward the center portion side of the bag-like body. Heat sealing by projecting the sealed upper heat seal part and the lateral center part of the fifth side part and the sixth side part from the bag bottom part side of the bag-like body toward the center part side of the bag-like body A lower heat seal part is provided , and an upper inclined heat seal part that is heat-sealed in an inclined manner from the upper heat seal end part on both the left and right sides of the upper heat seal part to the side heat seal part is provided, A lower inclined heat seal portion that is heat-sealed in an inclined manner is provided from the lower heat seal end portions on the left and right sides of the lower heat seal portion in the lateral direction to the side heat seal portion, and the packaging bag is laid sideways In this state, the packaging bag is heated and placed in a microwave oven, so that it is possible to exhaust water vapor without placing upper and lower restrictions on how to place the packaging bag itself. The blowout of contents other than water vapor can also be suppressed, and in addition, it can be configured without using an easy peel resin. Furthermore, expansion deformation can be suppressed more than other portions at both lateral ends of the upper surface portion and the lower surface portion in the vicinity of the bag bottom portion, and the water vapor is ventilated at the central portion of the upper heat seal portion and the lower heat seal portion, and further, the ventilation. Concentrate on the planned part.

According to the automatic ventilation packaging bag of the invention of claim 2, the bag is formed of a film body, has a bag bottom and an opening, constitutes a bag-shaped main body, and automatically vents between an upper surface portion and a lower surface portion of the bag-shaped main body. An intermediate portion is provided, and in the bag bottom portion, a first side portion is provided on the upper surface portion, and a sixth side portion is provided on the lower surface portion, and between the first side portion and the sixth side portion. The second side, the third side, the fourth side, and the fifth side are provided in this order, and the intermediate portion includes the second side, the third side, the fourth side, and the fifth side. Folding side portions into a W-shaped cross-sectional view and forming the third side portion and the fourth side portion in a direction projecting from the center portion of the bag-like body toward the bag bottom side, the upper surface portion and the lower surface A heat-sealing part of each side part of the part is heat-sealed to form a side heat-seal part, wherein the automatic ventilation part An intermediate heat seal portion in which the third side portion and the fourth side portion of the intermediate portion are heat-sealed in a band shape in the lateral direction of the bag-shaped main body, and a central position in the lateral direction of the intermediate heat seal portion. The third heat seal portion is connected to the intermediate heat seal portion, and is narrower than the heat seal width of the intermediate heat seal portion, and protrudes in an arc shape toward the center portion side of the bag-like body from the intermediate heat seal portion. The intermediate heat is obtained by folding the third side part and the fourth side part shorter than the horizontal heat seal length of the intermediate heat seal part. A cylindrical portion connected to the seal portion and the planned ventilation portion and formed in parallel with the intermediate heat seal portion, and an exhaust portion for exhausting water vapor that has passed through the planned ventilation portion to both ends of the cylindrical portion to the outside And a pocket portion having the first side portion and the second side portion in the lateral direction projecting from the bag bottom portion side of the bag-like body toward the center portion side of the bag-like body. Heat sealing by projecting the sealed upper heat seal part and the lateral center part of the fifth side part and the sixth side part from the bag bottom part side of the bag-like body toward the center part side of the bag-like body A lower heat seal part is provided, and an upper inclined heat seal part that is heat-sealed in an inclined manner from the upper heat seal end part on both the left and right sides of the upper heat seal part to the side heat seal part is provided, The lower heat seal part is provided with a lower inclined heat seal part that is heat-sealed in an inclined manner from the lower heat seal end part on both the left and right sides of the lower heat seal part to the side heat seal part, and the upper heat seal end The portion is formed as a narrow portion, and the heat seal amount of the narrow portion of the upper heat seal end is formed smaller than the heat seal amount of the central portion of the upper heat seal portion, and the lower heat seal end The portion is formed as a narrow portion, and the heat seal amount of the narrow portion of the lower heat seal end is formed smaller than the heat seal amount of the central portion of the lower heat seal portion, and the packaging bag Is placed in a microwave oven in a laid-down state, and the packaging bag is heated, so that it is possible to exhaust water vapor without placing upper and lower restrictions on how to place the packaging bag itself, Furthermore, the blowout of contents other than water vapor can also be suppressed, and in addition, it can be configured without using an easy peel resin. Furthermore, expansion deformation can be suppressed more than other portions at both lateral ends of the upper surface portion and the lower surface portion in the vicinity of the bag bottom portion, and the water vapor is ventilated at the central portion of the upper heat seal portion and the lower heat seal portion, and further, the ventilation. Concentrate on the planned part.

According to the automatic ventilated packaging bag of the invention of claim 3, in the invention of claim 1 or 2 , the belt-like heat seal width of the intermediate heat seal portion decreases from the side portion side to the vented portion. In addition, the expansion deformation pressure of the bag-like main body can be concentrated on the central portion, so that the planned ventilation portion can be easily broken.

According to the automatic ventilated packaging bag of the invention of claim 4, in the invention of any one of claims 1 to 3 , since the exhaust part is provided with an incompletely sealed part, water drops during retort sterilization It is possible to ensure the exhaust of water vapor while preventing the intrusion of water.

According to the automatic ventilating packaging bag of the invention of claim 5, in the invention of any one of claims 1 to 4 , the first side and the sixth side in the vicinity of both lateral ends of the intermediate heat seal part. Since the heat seal surfaces of the film body are heat-sealed, the intermediate part with the automatic ventilation part is fixed at an intermediate position between the upper surface part and the lower surface part, and is a W-shaped cross-sectional view composed of each side part Is maintained and displacement of the automatic vent is avoided. Further, the expansion at both lateral ends of the bag bottom is restricted, and the water vapor is concentrated on the planned ventilation portion.

  According to the automatic ventilation packaging bag of the invention of claim 6, in the invention of any one of claims 1 to 5, the upper surface portion, the lower surface portion, and the intermediate portion are formed by bending a single film body. Therefore, it is easy to make an automatic ventilation packaging bag, and it is possible to maintain the strength of the bent portion of each side portion.

  According to the automatic ventilation packaging bag storage box according to the invention of claim 7, a rectangular parallelepiped storage box for storing the automatic ventilation packaging bag according to any one of claims 1 to 6, wherein the box of the storage box Openings are provided opposite to each other, one of the box openings is sealed by an easy opening portion and the other is sealed by a fixed sealing portion, and the easy opening portion is a receding portion at the center in the lateral direction of the easy opening portion. A planar convex shape having an arcuate bulging portion that penetrates the receding portion at the center in the lateral width direction of the easy-opening portion, and has a concave edge portion in a planar shape provided with Suitable for packaging of automatic ventilation packaging bags because the automatic ventilation packaging bags are arranged and accommodated on the easy-opening portion side. To obtain an automatic ventilation packaging bag storage box that can be heated in a microwave oven together with a storage box that can easily cope with expansion deformation It can be.

  According to the automatic ventilated packaging bag storage box according to the invention of claim 8, in the invention of claim 7, the lower surface easily bent portion and the bulging portion that extend from the starting point of the retracted portion in the easy opening portion to the box lower surface portion Since the upper surface easy-bending part that the box upper surface part extends from the starting point is provided, the rigidity of the storage box is lowered, and the box upper surface part and the box lower surface part in the vicinity of the easy-opening part are appropriately bent, and automatic ventilation packaging It is possible to easily cope with the expansion deformation of the bag.

  According to the automatic ventilation packaging bag storage box according to the invention of claim 9, in the invention of claim 7 or 8, either or both of the fixed sealing part and the easy-opening part are provided with a box self-supporting leg part. Therefore, it is convenient when the box made of the automatic ventilation packaging bag is made up.

1 is an overall perspective view of an automatic ventilation packaging bag according to an embodiment of the present invention. It is a cross-sectional schematic diagram of the bending of the film body in a bag bottom part. It is a principal cross-sectional schematic diagram of a bag bottom part. It is a main upper surface schematic diagram of an automatic ventilation part. It is a principal part enlarged view of FIG. It is an expansion conceptual diagram of an automatic ventilation packaging bag. It is a principal cross-sectional schematic diagram at the time of expansion | swelling of FIG. It is a front view from the bag bottom part side of the automatic ventilation packaging bag at the time of expansion | swelling. It is a perspective view from the bag bottom part side of the automatic ventilation packaging bag at the time of expansion | swelling. It is an example of the 1st formation method of an automatic ventilation packaging bag. It is an example of the 2nd formation method of an automatic ventilation packaging bag. It is a completed example of an automatic ventilation packaging bag. It is a whole perspective view of the automatic ventilation packaging bag accommodation packaging box of the embodiment of the present invention. It is an expanded view of an automatic ventilation packaging bag accommodation packaging box. It is a whole perspective view of the display state of an automatic ventilation packaging bag accommodation packaging box. It is a whole perspective view of the half opening state of an easy-opening part. It is a whole perspective view of the full opening state of an easy-opening part. It is a photograph at the time of heating of an automatic ventilation packaging bag. It is a photograph at the time of heating the whole automatic ventilation packaging bag accommodation packaging box.

  A preferred embodiment of an automatic ventilated packaging bag defined in the present invention will be described from the overall structure with reference to FIGS. This automatic ventilation packaging bag 1 is mainly used for packaging food and drinks, and is sterilized by retort after filling. And it is a packaging bag in which the whole packaging bag is put in a microwave oven (high frequency range, microwave oven) and can be cooked. As defined in the invention of claim 1, the automatic ventilation packaging bag 1 is entirely made of a film body F and is formed by folding and heat sealing. The automatic ventilation packaging bag 1 is provided with a bag bottom 14 and an opening 15 to constitute a bag-shaped main body 10. In the figure, the contents are sealed and the opening 15 is sealed. The opening 15 is sealed to become an opening heat seal part 33. As illustrated, the bag-shaped main body 10 is provided with an upper surface portion 11 and a lower surface portion 12. An intermediate portion 13 having an automatic ventilation portion 20 is provided between the upper surface portion 11 and the lower surface portion 12. Each of the side portions 31 and 31 of the upper surface portion 11 and the lower surface portion 12 is provided with a heat seal surface having a predetermined width, and the heat seal surfaces are heat sealed to form side heat seal portions 32 and 32.

  In the automatic ventilated packaging bag 1 of FIG. 1, reference numeral 34 is a folding fixing part, 35 is an upper heat seal part, 36 is a lower heat seal part, 51 is an intermediate heat seal part, 52 is a vented part, 53 is a pocket part, 54 Is a cylindrical part, 55 is an exhaust part, and 56 is an incompletely sealed part. In FIG. 1 and the subsequent figures, Dl, Ds, and Dh are directional arrows indicating the positional relationship of the automatic ventilation packaging bag. Dl indicates the vertical direction (length direction) of the automatic ventilation packaging bag, Ds indicates the horizontal direction (horizontal width direction), and Dh indicates the height direction.

  As shown in the schematic sectional view of the folding of the film body F in FIG. 2, the bag-shaped main body 10 of the automatic ventilation packaging bag 1 is provided with an intermediate portion 13 at the bag bottom portion 14. According to the bending of the bag bottom 14 of the bag-shaped main body 10, the first side 21 is provided on the upper surface 11 and the sixth side 26 is provided on the lower surface 12. The second side 22, the third side 23, the fourth side 24, and the fifth side 25 are provided in this order between the first side 21 and the sixth side 26. Each side portion 21 to 26 is formed in a zigzag shape by bending. Among these, the intermediate part 13 is formed by folding the second side part 22, the third side part 23, the fourth side part 24, and the fifth side part 25 into a W shape in a sectional view. Further, the third side portion 23 and the fourth side portion 24 that form the intermediate portion 13 are formed in a direction protruding from the central portion Cp of the bag-shaped main body 10 toward the bag bottom portion 14. That is, the automatic ventilation part 20 provided in the intermediate part 13 can be protruded outside.

  Further, referring to FIGS. 10 and 11 described later together with FIG. 2, the upper surface portion 11, the intermediate portion 13, and the lower surface portion 12 are formed by bending a single film body F as defined in the invention of claim 6. Is done. This is because it is effective in facilitating bag-making of the automatic ventilation packaging bag 1 and maintaining the strength of the bent portion of each side portion. There is no risk that water vapor and contents break through the film itself of the folded portion where a single film is folded and leak from the packaging bag, and water vapor can be appropriately guided to the planned ventilation portion 52 provided in the automatic ventilation portion 20. It is.

  As the film body F, a film which is a known retort packaging material is used. Film body F is a biaxially stretched film made of polypropylene film, polyamide film, polyester film, ethylene-vinyl alcohol copolymer, etc., aluminum oxide-deposited biaxially stretched polyester film, silica-deposited biaxially stretched polyester film, polymetaxylylene azide Examples thereof include heat-resistant films that can be applied to microwave ovens (high-frequency ranges), such as amide polyamide stretched films or coextruded laminated films of these with 6-nylon or the like. Normally, the listed films are formed by laminating (laminating) a film of a sealant film that is in contact with the contents and is fused to each other by heat sealing, and a polyamide resin film and a polyester resin film that protect the film. Or it is a laminated film of three or more layers. In the film body, the thickness of each film layer, the number of layers, the resin composition, the characteristics of the contents, the heat resistance temperature, the heat seal temperature, the strength as a packaging bag, the distribution route, the distribution form, etc. are comprehensively considered and selected. . For example, ZK93KM manufactured by Toray Film Processing Co., Ltd. is used for polypropylene films, and SP-R manufactured by Mitsubishi Plastics, Inc. is used for polymetaxylylene adipamide-based polyamide stretched films.

  The structure of the intermediate part 13 and the automatic ventilation part 20 will be described with reference to a partial sectional view of FIG. 3 and a schematic top view of FIG. FIG. 3 schematically shows a longitudinal section in the middle of the lateral direction Ds in the vicinity of the bag bottom 14 of the automatic ventilation packaging bag 1. The contents C are enclosed in the interior 10i of the bag-shaped main body 10 of the automatic ventilated packaging bag 1, and the illustration shows a state before heating by the microwave oven.

  After folding the first side part to the sixth side parts 21, 22, 23, 24, 25, 26, the upper heat seal part 35 is formed by heat sealing the first side part 21 and the second side part 22, The lower heat seal portion 36 is formed by heat sealing the fifth side portion 25 and the sixth side portion 26.

  Looking at the automatic ventilation part 20, the third side part 23 and the fourth side part 24 located in the intermediate part 13 are heat-sealed in a band shape, and an intermediate heat seal part 51 is formed. A cylindrical part 54 derived from the third side part 23 and the fourth side part 24 is formed by folding the third side part 23 and the fourth side part 24 and partially heat-sealing the intermediate heat seal part 51. . Therefore, an exhaust portion 55 for passing water vapor is formed, and a pocket portion 53 having a bag shape as a whole is formed. As shown in the figure, the cylindrical portion 54 is not heat-sealed and serves as a water vapor passage path.

  In the intermediate heat seal portion 51, a portion where the heat seal adhesion is broken by the water vapor actually generated from the contents C and the water vapor is released from the inside 10 i of the bag-shaped main body 10 is a ventilation portion 52. As shown in FIGS. 1 and 3, both ends of the upper heat seal portion 35 and the lower heat seal portion 36 are fixed by a folding fixing portion 34. For this reason, the intermediate part 13 and the automatic ventilation part 20 included therein are always located approximately in the middle of the bag-like main body 10 in the vertical direction (Dh). Therefore, when cooking (heating) the automatic ventilation packaging bag 1, it can be placed in the microwave oven without being aware of the position of the automatic ventilation unit 20 and the top and bottom of the automatic ventilation packaging bag 1. For convenience of explanation, the automatic ventilation packaging bag 1 is described using upper and lower words, but the structure of the upper and lower parts is the same, and the vertical direction is not questioned.

  FIG. 4 is a schematic diagram in which the upper surface portion 11, the upper heat seal portion 35, and the like are omitted for explaining the automatic ventilation portion 20. The third side portion 23 and the fourth side portion 24 located in the intermediate portion 13 are heat-sealed in a band shape in the lateral direction (Ds) of the bag-like main body 10 (see FIG. 3 and the like), and the intermediate heat seal portion 51 is formed. . The ventilation plan part 52 is arranged at the center position in the lateral direction (Ds) of the intermediate heat seal part 51 and is connected to the intermediate heat seal part 51. The intermediate heat seal part 51 and the ventilation plan part 52 are integrally formed by heat sealing of the third side part 23 and the fourth side part 24.

  The heat seal width W <b> 2 of the planned ventilation portion 52 is formed to be narrower than the heat seal width W <b> 1 of the intermediate heat seal portion 51. That is, W2 <W1. By narrowing the heat seal width, the adhesion strength of the film body is intentionally suppressed, and the adhesion between the films by heat sealing can be broken (collapsed) first due to expansion deformation accompanying the generation of water vapor in the bag-like body 10 Yes.

  Furthermore, the ventilation plan part 52 is formed so as to protrude in an arc shape toward the center part Cp side of the bag-like main body 10 from the intermediate heat seal part 51. In the drawing, a portion having a flat trapezoidal shape and closest to the central portion Cp is a linear pressure receiving portion 58. By causing the planned ventilation portion 52 to protrude toward the central portion Cp without being buried in the intermediate heat seal portion 51, the planned ventilation portion 52 is likely to be initially subjected to the expansion deformation pressure of the bag-like main body 10. That is, the force which the heat-sealed edge parts try to separate is received first. In addition, by providing the linear pressure receiving portion 58 in the ventilation plan portion 52, pressure is evenly applied to the pressure receiving portion 58. Therefore, the pressure receiving portion 58 is uniformly broken, and a relatively large water vapor passage region can be formed in the planned ventilation portion 52.

Here, as defined in the invention of claim 3 , the belt-like heat seal width W <b> 1 of the intermediate heat seal portion 51 decreases from the side portion 31 side to the planned ventilation portion 52. In the drawing, the left and right in the horizontal direction (Ds) of the planned ventilation portion 52 are formed as an intermediate narrow heat seal portion 57, and the heat seal width W3 of the intermediate narrow heat seal portion 57 is narrower than the aforementioned W1. W3 <W1. The expansion shape of the bag-shaped main body 10 can be controlled by narrowing the heat seal width of the intermediate heat seal portion 51 toward the center portion. Therefore, the expansion deformation pressure of the bag-shaped main body 10 is likely to concentrate on the central portion, and the destruction of the planned ventilation portion 52 becomes more reliable. Furthermore, the heat seal width W2 of the planned ventilation portion 52 is set to be narrower than the heat seal width W3 of the intermediate narrow heat seal portion 57, and the effect of making the planned ventilation portion narrower than the aforementioned intermediate heat seal portion. Is maintained.

  The water vapor that has passed through the planned ventilation portion 52 is exhausted to the outside of the automatic ventilation packaging bag 1 through a pocket portion 53 having a cylindrical portion 54 and an exhaust portion 55. The cylindrical portion 54 is formed by folding the third side portion 23 and the fourth side portion 24, and is formed shorter than the heat seal length in the lateral direction (Ds) of the intermediate heat seal portion 51. The cylindrical portion 54 is connected to the intermediate heat seal portion 51 and the planned ventilation portion 52 and is formed in parallel with the lateral width direction of the intermediate heat seal portion 51.

  When the horizontal width of the cylindrical portion 54 becomes too long, the flexibility of the cylindrical portion 54 itself is lowered due to the rigidity of the film itself, and the expansion deformation of the bag-shaped main body 10 is likely to deteriorate. On the contrary, when the horizontal width of the cylindrical part 54 is too short with respect to the horizontal width of the intermediate heat seal part 51, it is considered that the tubular part 54 is insufficient in receiving the contents ejected from the aeration planned part 52 together with the water vapor. Therefore, from the balance of both, the horizontal width of the cylindrical portion 54 is appropriately about 0.4 to 0.7 times the heat seal length of the intermediate heat seal portion 51 in the horizontal width direction.

  The exhaust portions 55 are disposed at the left and right ends of the cylindrical portion 54 in the lateral direction (Ds). In this arrangement, the content ejected together with the water vapor that has passed through the planned ventilation portion 52 can collide with the cylindrical portion 54 and be held in the cylindrical portion 54. Therefore, inadvertent ejection (blowing) of the contents from the automatic ventilation packaging bag 1 is avoided. As shown in the figure, the cross-sectional area of the flow path portion through which the water vapor passes can be increased by setting the planned ventilation portion 52 and the cylindrical portion 54 to an appropriate size. For this reason, the water vapor pressure decreases when passing through the ventilation portion 52 and the cylindrical portion 54. From this, the speed of the contents ejected together with the steam also decreases in the same way as the steam pressure decreases, so that the possibility that the ejected contents move through the cylindrical part 54 and leak from the exhaust part 55 is substantially suppressed. The

3 and 4 will be further described with the enlarged view of the main part of FIG. The exhaust portion 55 is provided with an incompletely sealed portion 56 as defined in the invention of claim 4 . The incompletely sealed portion 56 is vertically sealed by heat-sealing in the form of dots to the left and right end portions in the horizontal direction (Ds) of the cylindrical portion 54 generated by folding the third side portion 23 and the fourth side portion 24. This is a structure in which the side portions 23 and 24 of the two are partially fused. In the figure, the heat seal is a dot array. By providing the incompletely sealed portion 56 of the point heat seal, the exhaust portion 55 is secured to have an opening that does not hinder the ventilation. Note that the form of the incompletely sealed portion 56 includes an appropriate line shape in addition to the illustrated dot shape.

  The automatic ventilated packaging bag 1 is filled with food and drink and the opening is sealed, and then loaded into a retort kettle and the like, and steam is introduced under high pressure to be sterilized by retort. When the opening amount of the exhaust part 55 is too large, water vapor at the time of retort sterilization enters the cylindrical part 54 and cools and easily remains in the pocket part 53 as droplets. Due to the structure of the cylindrical portion 54, it is not easy to remove water droplets. For this reason, the incomplete sealing part 56 is provided in order to suppress the penetration | invasion of water vapor | steam as much as possible.

  As can be clearly understood from FIGS. 1 to 5, the first side portion 21 and the second side portion 22 are folded and heat-sealed in the lateral direction (Ds) at the end portion of the bag bottom portion 14. And in the center part M1 (FIG.5 (b)) of a horizontal direction (Ds), the upper heat seal part 35 is formed toward the center part Cp side from the bag bottom part 14 side of the bag-shaped main body 10. FIG. The upper heat seal portion 35 has a shape that protrudes in a triangular shape or a trapezoidal shape or an arc shape by increasing the heat seal amount of the first side portion 21 and the second side portion 22.

  Similarly, the fifth side 25 and the sixth side 26 are also folded and heat-sealed in the lateral direction (Ds) at the end portion of the bag bottom 14. And in the center part M2 (FIG.5 (b)) of a horizontal direction (Ds), the lower heat seal part 36 is formed toward the center part Cp side from the bag bottom part 14 side of the bag-shaped main body 10. FIG. The lower heat seal portion 36 also has a shape protruding in a triangle or trapezoidal shape or an arc shape by increasing the heat seal amount of the fifth side portion 25 and the sixth side portion 26 (see FIG. 4).

  The protruding shapes of the upper heat seal portion 35 and the lower heat seal portion 36 are employed because it is necessary to cause a curved shape deformation in the vicinity of the bag bottom portion 14 when the bag-shaped main body 10 is inflated. Details will be described with reference to FIGS.

With the disclosure of FIGS. 4, 5 (a), 5 (b), etc., upper inclined heat seal portions 41 are provided on the left and right sides of the upper heat seal portion 35 in the lateral direction (Ds). Heat sealing is performed in an inclined manner from the respective end portions (upper heat sealing end portion 43) of the heat sealing portion 35 to the side heat sealing portion 32 toward the center portion Cp side. Similarly, lower inclined heat seal portions 42 are provided on both the left and right sides of the lower heat seal portion 36 in the lateral direction (Ds). The lower inclined heat seal portion 42 is heat-sealed in an inclined manner from the respective end portions (lower heat seal end portion 44) of the lower heat seal portion 36 toward the side portion heat seal portion 32 toward the central portion Cp.

  The upper inclined heat seal portion 41 and the lower inclined heat seal portion 42 are formed by being heat sealed in a substantially triangular shape. In the illustrated example, the upper heat seal end portion 43 of the upper inclined heat seal portion 41 is formed as a narrow portion 45. The lower heat seal end portion 44 of the lower inclined heat seal portion 42 is also formed as the narrow portion 46. The heat seal amount E1 of the narrow portions 45 and 46 is smaller than the heat seal amount E2 of the central portion M1 of the upper heat seal portion 35 and the central portion M2 of the lower heat seal portion 36 (see FIG. 4).

  By providing a difference in the heat seal amount, the upper inclined heat seal portion 41 and the lower inclined heat seal portion 42 are prevented from expanding the bag-shaped main body 10. In contrast, the upper heat seal end portion 43 and the lower heat seal end portion 44 having a small heat seal amount are more likely to expand. However, in the upper heat seal part 35 and the lower heat seal part 36, the heat seal amount is increased and the expansion of the bag-shaped main body 10 is suppressed. Details of the expansion will be described later with reference to FIGS.

  The upper inclined heat seal portion 41 and the lower inclined heat seal portion 42 shown in the figure have a larger heat seal area than the upper heat seal portion 35 and the lower heat seal portion 36, and have a shape that bites into the bag-shaped main body 10. For this reason, expansion deformation is suppressed more than other portions at both lateral ends of the upper surface portion 11 and the lower surface portion 12 near the bag bottom portion 14. For this reason, the water vapor tends to concentrate toward the central portion of the upper heat seal portion 35 and the lower heat seal portion 36 and further toward the ventilation planned portion 52 of the automatic ventilation portion 20 at the center of the intermediate portion 13. As a result, the exhaust efficiency of water vapor from the automatic ventilation part 20 is increased.

  The manner in which the bag-like main body 10 of the automatic ventilation packaging bag 1 is expanded and deformed by water vapor will be described with reference to FIGS. FIG. 6 is a schematic diagram showing a flat shape in which the upper surface portion 11, the upper heat seal portion 35, and the like are omitted, and the expansion is omitted for the sake of convenience, for the explanation of the automatic ventilation portion 20, as in FIG. 4. FIG. 6A shows the heating stage of the automatic ventilation packaging bag 1. The water vapor Vp (thick solid arrow) generated from the contents C in the interior 10i of the bag-shaped main body 10 is filled in the bag-shaped main body 10. Since the internal pressure at this point accompanying the generation of water vapor is lower than the heat seal strength of each part, the heat seal part is not broken. FIG. 6B shows a state in which the heating has further progressed, the amount of water vapor generated is increased, the internal pressure is increased, and the heat seal of the planned ventilation portion 52 is finally broken.

  The heat sealing amount (width) of the ventilation plan part 52 is the smallest among any parts of the automatic ventilation packaging bag 1. In other words, it is a weak part intentionally formed. Then, coupled with the undulating expansion shape at the bag bottom 14 of the bag-shaped main body 10, the fracture opening 50 is generated in the planned ventilation portion 52 (pressure receiving portion 58). As in the shape of the planned ventilation portion 52 (pressure receiving portion 58) in FIG. 6B, a hole having a size corresponding to the planned ventilation portion 52 is generated in the intermediate heat seal portion 51 due to the destruction of the narrow heat seal portion. Once the destruction opening 50 is generated in the planned ventilation portion 52, the size of the destruction opening 50 generated in the ventilation portion 52 relative to the size of the bag-like main body 10 is relatively large with respect to the bag-like main body. Therefore, the exhaust of water vapor is performed smoothly, and the internal pressure is immediately reduced. In this way, excessive expansion and rupture of the automatic ventilated packaging bag 1 is avoided, and the internal water vapor is safely exhausted.

  The flow of the water vapor Vp after passing through the breaking opening 50 comes into contact with the cylindrical portion 54 of the pocket portion 53, and then is divided into left and right and is exhausted from the exhaust portion 55 to the outside of the automatic ventilation packaging bag 1. Since the incompletely sealed portion 56 provided in the exhaust portion 55 has a dot shape, the water vapor Vp can pass through the gap and does not affect the water vapor exhaust (see the thick solid arrow in the drawing). Moreover, the cylindrical part 54 of the pocket part 53 is formed in the horizontal direction (Ds) longer than the ventilation plan part 52 (destructive opening part 50). For this reason, even when the contents are ejected together with water vapor from the breaking opening 50 at a wide angle, it collides with the cylindrical portion 54 and is held in the pocket portion 53. That is, inadvertent ejection (blowing) of the contents from the automatic ventilated packaging bag 1 is avoided, and the risk of contamination in the microwave oven is further reduced.

  FIG. 7 schematically shows a longitudinal section in the middle of the lateral direction (Ds) in the vicinity of the inflated bag bottom 14 in the automatic ventilated packaging bag 1. The illustration shows a state in which the planned ventilation portion 52 is broken by being heated by a microwave oven. As can be seen from the comparison with FIG. 3 described above, the bag-shaped main body 10 is greatly expanded in the height direction (Dh) by the generated water vapor. Moreover, the 2nd side part 22 and the 5th side part 25 are extended with the shape deformation at the time of expansion | swelling. Therefore, the pocket portion 53 of the automatic ventilation portion 20 located at the intermediate portion 13 is attracted to the second side portion 22 or the fifth side portion 25 and warps. In the figure, it is in a state of being bent toward the second side 22. The reverse direction is not shown.

  Even when the automatic ventilation packaging bag 1 is in an expanded state, the automatic ventilation portion 20 itself continues to be positioned at the intermediate portion 13. The automatic ventilation portion 20 is not greatly displaced at the bag bottom portion 14 and is located at a substantially intermediate position between the upper surface portion 11 and the lower surface portion 12 before and after the expansion deformation. Therefore, as is obvious from the drawing, when the automatic ventilation packaging bag 1 is placed at a predetermined position in the microwave oven, it can be used without considering which one is up and down.

  FIG. 8 is a front view from the bag bottom side, and FIG. 9 is a perspective view from the bag bottom side, both of which are in an expanded state of the automatic ventilation packaging bag 1. In the left and right upper inclined heat seal portions 41 and the left and right lower inclined heat seal portions 42 of the bag bottom portion 14, the expansion is suppressed by the size of the heat seal amount. Further, the ends of the left and right upper inclined heat seal portions 41 and the left and right lower inclined heat seal portions 42 are fixed to each other by a folding fixing portion 34 (see FIG. 11). Therefore, expansion is restricted at both ends in the lateral direction (Ds) of the bag bottom 14 of the bag-shaped main body 10. Therefore, first, the expansion pressure of the water vapor is concentrated on the planned ventilation portion 52 of the automatic ventilation portion 20 located in the central portion in the lateral direction (Ds).

  Next, the upper heat seal end portion 43 is set as the narrow portion 45, and the lower heat seal end portion 44 is set as the narrow portion 46, and the heat seal amount is set small. For this reason, the said part protrudes by expansion deformation. The water vapor regulated by both lateral ends of the bag bottom portion 14 is directed toward the narrow portion 46 at the upper heat seal end portion 43 (narrow portion 45) and the lower heat seal end portion 44.

  Here, since the heat seal amount of the upper heat seal part 35 and the lower heat seal part 36 increases, the expansion deformation amount of the film body is suppressed. Then, the initial position state in the automatic ventilation packaging bag before the generation of water vapor is easily preserved. Therefore, due to the influence of the upper heat seal portion 35 and the lower heat seal portion 36, the portion of the planned ventilation portion 52 at the center in the lateral direction of the intermediate heat seal portion 51 is recessed again inside the bag-shaped main body. Therefore, as shown in the drawing, the bag bottom portion 14 of the bag-shaped main body 10 has an inflated shape having concave, convex, concave, convex, and concave undulations along the lateral direction (Ds).

  More specifically, when the entire bag is inflated with water vapor generated by heating the microwave oven, the water vapor is concentrated in the planned ventilation portion 52 by utilizing the expansion force of the water vapor. At this time, the pocket portion 53 (cylindrical portion 54) is also pushed by the pressure of water vapor. Even if the heat seal of the planned ventilation portion 52 is broken, if the pocket portion 53 (tubular portion 54) itself does not swell, the passage and exhaust of water vapor will be incomplete, and the heat seal of the planned ventilation portion 52 will be broken. Even if it is done, there is a possibility that ventilation is not performed. As a countermeasure to this problem, an upper heat seal part 35 and a lower heat seal part 36 which have already been shown and described in detail are provided. The opening part (breaking opening part 50) of the ventilation plan part 52 is expanded from the expansion shape with the uneven | corrugated wave | undulation resulting from the heat seal shape of the upper heat seal part 35 and the lower heat seal part 36, and the shape is further hold | maintained. . As a result, the water vapor can stably pass through the pocket portion 53 (cylindrical portion 54), the exhaust efficiency is good, and the expansion burst is avoided.

  Since the water vapor pressure is equally applied to the inside of the bag-like main body, an elliptical shape or a spindle-shaped shape is realistic considering the safe shape when the bag-like main body is inflated. In consideration of the expansion shape guided to the automatic ventilation portion, it is conceivable to arrange the ventilation portion at the end portion of an elliptical shape or a spindle shape. However, in the case of the shape, since the bag-shaped main body is uniformly expanded by the water vapor pressure, the bag-shaped main body is also considerably expanded before the heat-seal destruction of the planned ventilation portion occurs. Therefore, in the past, an easy peel resin film that causes cohesive failure and delamination was placed in the planned ventilation section for the heat seal breakdown of the planned ventilation section, and the planned ventilation section was destroyed before excessive expansion of the bag-shaped body. The steam generated inside was exhausted.

  On the other hand, in the present invention, by adopting the inflated shape having uneven undulations disclosed in FIGS. Conceivable. Therefore, due to both actions, the force at which the films (sides) are separated from each other in the vicinity of the planned ventilation portion is larger than that in other heat seal portions. Furthermore, as will be described in detail with reference to FIG. 4 and the like, the aeration planned portion protrudes toward the center portion side of the bag-like main body from the intermediate heat seal portion, and is narrow. Therefore, the planned ventilation portion receives the detachment force between the films (side portions) generated by the action of both the steam pressure and the strain deformation force, and the heat seal fusion is broken faster than any part. As a result, a water vapor passage path is generated, and the water vapor is exhausted from the bag-shaped body. As can be seen from this, by improving the shape and structure of the bag-like main body and the planned ventilation portion, water vapor can be exhausted even if the easy peel resin film is omitted.

  An example of a method for forming the automatic ventilation packaging bag 1 will be described with reference to FIGS. 10 to 12. Of course, there may be procedures and forming methods other than those shown. As shown in FIG. 10A, the film body F is bent to the upper surface portion 11 side and the lower surface portion 12 side at a portion to be the intermediate portion 13. By this bending, a pocket portion 53 and the like are generated from the third side portion 23 and the fourth side portion 24.

  In FIG.10 (b), the hot plate (not shown) of a heat seal apparatus is pressed with respect to the folded part, and it heat-seals from an up-down direction, and the upper surface part 11 and the lower surface part 12 are integrated. From the viewpoint of work efficiency, the hot plate has a shape adapted to the shapes of the intermediate heat seal portion 51 and the planned ventilation portion 52, and the intermediate heat seal portion 51 and the planned ventilation portion 52 are collectively collected by pressing the hot plate once. Formed. At this time, the incomplete sealing portion 56 is also formed by heat sealing simultaneously or sequentially. After forming the heat seal such as the intermediate heat seal portion 51, the cylindrical portion 54 is formed on the front side of the intermediate heat seal portion 51. The left and right ends in the lateral direction are cut off, and the exhaust part 55 is formed in the cut part 59. Reference numeral ct denotes a cut piece.

  According to FIG. 11A, the first side portion 21 and the second side portion 22 are bent at the upper surface portion 11. At this time, a part of the second side portion 22 is cut off as an upper cut-through portion 37. Similarly, the fifth side portion 25 and the sixth side portion 26 are also bent at the lower surface portion 12. A part of the fifth side portion is also cut out as a lower cut-out portion 38. The formation of the upper cut-out portion 37 exposes the first side portion 21 at the same portion, and the formation of the lower cut-out portion 38 exposes the sixth side portion 26 at the same portion.

  In FIG.11 (b), the 1st edge part 21 and the 2nd edge part 22 are the upper heat seal part 35 and the upper inclined heat seal part 41 on either side by the heat seal of the hot plate (not shown) of a heat seal apparatus. Is formed. Both heat seal portions are continued by the upper heat seal end portion 43. The fifth side portion 25 and the sixth side portion 26 also form a lower heat seal portion 36 and left and right lower inclined heat seal portions 42 by heat sealing of a hot plate (not shown) of the heat seal device. Both heat seal portions are continued by the lower heat seal end portion 44.

After the heat sealing of each part is completed, the intermediate part 13 provided with the automatic ventilation part 20 includes the upper surface part 11 (first side part 21 and second side part 22) and the lower side part 12 (fifth side part 25 and second side). Folded inside the side 26). And as prescribed | regulated to invention of Claim 5 , with the 1st edge | side part 21 exposed by the upper cutting part 37 located in the both ends of the horizontal direction (Ds) of the intermediate heat seal part 51, and the lower cutting part 38, The exposed sixth side 26 is heat sealed (see FIG. 12). In this way, formation of each part of the bag bottom part 14 of the bag-shaped main body 10 is completed, and the intermediate part 13 provided with the automatic ventilation part 20 is fixed to an intermediate position between the upper surface part 11 and the lower surface part 12. Therefore, the cross-sectional view W-shape formed from each side portion is maintained, and a position shift or the like of the automatic ventilation portion 20 is avoided.

  The film body F, which is a material for retort packaging, usually has a laminate structure having only one side of a sealant film layer that can be heat-sealed. Therefore, from the front-back relationship of the film body F, the second side 22 and the fifth side 25 cannot be directly fused by heat sealing. Therefore, in order to intentionally expose the sealant film layer, it is necessary to form the upper cut-out portion 37 and the lower cut-out portion 38.

  Finally, as shown in FIG. 12, the side portions 31 and 31 of the upper surface portion 11 and the lower surface portion 12 are heat-sealed to form side heat seal portions 32 and 32, respectively. Thus, the automatic ventilation packaging bag 1 is completed. The automatic ventilated packaging bag 1 is completed at the stage shown in the figure and shipped to individual consumers. In the consumer, the contents are filled from the opening 15 of the automatic ventilation packaging bag 1, and the opening 15 is subjected to heat seal sealing (opening heat seal portion 33), retort sterilization, and the like.

  The automatic ventilated packaging bag 1 can also be displayed on a product shelf as a vertically placed packaging bag (stand pack) depending on the size of each side of the bag bottom 14. The present invention is not limited to the illustrated form, and can be appropriately modified as long as the gist of the invention is satisfied. Further, in the figure, the hatched display (FIGS. 4 and 6) and the shaded display (FIGS. 10 to 12) indicate that the part is heat sealed.

  The automatic ventilation packaging bag storage box 7 (hereinafter also referred to as a storage box) for storing the automatic ventilation packaging bag 1 will be described with reference to FIGS. The storage box 7 is a storage box that can be carried into the microwave oven while the automatic ventilation packaging bag 1 is stored and heated as it is. The material of the storage box is not particularly limited, and is formed from paper (thick paper), a resin sheet, or the like. Paper is preferable from the standpoints of cost and disposal. In the explanation of the automatic ventilation packaging bag storage box 7, the vertical direction (length direction) of the automatic ventilation packaging bag storage box is Dl, and the horizontal direction (width direction) of the automatic ventilation packaging bag storage box is Ds because of the simplicity of the direction indication. The height direction of the automatic ventilation packaging bag storage box is used as Dh.

  As shown in the overall perspective view of the automatic ventilated packaging bag shown in FIG. 13 and inserted in the invention of claim 7, the box openings 70 of the storage box 7 are provided opposite to each other. In the figure, there are an opening opening 71 that opens later and a sealing opening 72 that maintains the sealing state. A sealing opening 72 that is one of the box openings 70 is sealed by a fixed sealing portion 74. And the opening opening part 71 used as the other side of the box opening part 70 is sealed by the easy opening part 73 (refer FIG. 15). When the above-mentioned automatic ventilation packaging bag 1 (contents filled) is accommodated inside the automatic ventilation packaging bag storage box 7, the automatic ventilation portion 20 of the automatic ventilation packaging bag 1 is disposed on the easy-opening portion 73 side. That is, it is for making it easy to cancel the sealing of the easy-open portion 73 in conjunction with the expansion of the automatic ventilation packaging bag 1. For the structural stability of the box opening 70, a folded piece 78 is provided in the box opening. Reference numeral 75 is a box upper surface portion, 77 is a box side surface portion, 92 is an upper surface easily bent portion, and 95 is a box free standing leg portion (cut leg piece).

  As can be seen from the developed view of FIG. 14, the easy opening portion 73 in the opening portion 71 is provided with a concave edge 81 and an arcuate edge 83. The concave edge 81 has a concave shape in a plan view in which a U-shaped retracted portion 82 is provided at the central portion in the lateral direction (Ds) of the easy-opening portion 73, and extends to the box lower surface portion 76. The arcuate edge 83 has a convex shape in a plan view in which an arcuate bulging portion 84 is provided at the central portion in the lateral direction (Ds) of the easy-opening portion 73 and extends to the box upper surface portion 75. The lateral width of the bulging portion 84 of the arc-shaped edge portion 83 is invaded into the retracted portion 82 of the concave edge portion 81, and therefore both have the same width.

  The fixed sealing portion 74 in the sealing opening 72 is provided with a concave edge portion 81 and a convex edge portion 85. The concave edge 81 has a concave shape in plan view similar to that of the opening opening 71 and extends to the box lower surface 76. The convex edge portion 85 is a convex shape in plan view in which a convex piece portion 86 having an angular convex shape is provided at the central portion in the lateral direction (Ds) of the fixed sealing portion 74, and extends to the box upper surface portion 75. Established. The sealing opening 72 is also provided with a folded piece 78.

  In the engagement accompanying the folding of the concave edge 81 and the convex edge 85 constituting the fixed sealing portion 74 on the sealing opening 72 side, the angular convex piece 86 bites into the retracted portion 82 in a large amount. As a result, the resistance increases, and the engagement is not released easily and stable fixing is possible. On the other hand, in the engagement accompanying the folding of the concave edge portion 81 and the arc-shaped edge portion 83 constituting the easy opening portion 73 on the opening opening portion 71 side, the bulging portion 84 becomes an arc shape and bites into the retreat portion 82. The amount is relatively small. For this reason, since the contact area between the two is small and the generated resistance is also small, the engagement is easily released by a relatively small force. Thus, the easiness of opening between the box openings 70 can be adjusted by changing the shapes.

  In addition, as defined in the invention of claim 8, there is a lower surface easily bent portion 91 (bending auxiliary line) extending from the starting point 87 of the retracted portion 82 of the recessed edge portion 81 to the box lower surface portion 76 in the easy opening portion 73. Provided. Further, an upper surface easy-bending portion 92 (bending auxiliary line) extending from the starting point 88 of the bulging portion 84 of the arc-shaped edge portion 83 in the easy-opening portion 73 to the box upper surface portion 75 is provided. In the drawing, it is a thin solid line. Both the upper surface easily bent portion 92 and the lower surface easily bent portion 91 are two grooves formed in the plate material of the automatic ventilated packaging bag storage box 7, and the distance from each other is narrowed toward the center of the storage box. It is formed in a reverse C shape inside the box from the starting point. When the automatic ventilated packaging bag 1 expands with heating, stress concentrates along the grooves of the upper surface easily bent portion 92 and the lower surface easily bent portion 91. Therefore, a portion where the rigidity of the material of the storage box 7 is reduced is generated, and the box upper surface portion 75 and the box lower surface portion 76 in the vicinity of the easy-opening portion 73 are easily bent appropriately. Therefore, the load of shape deformation on the upper and lower surface portions is reduced.

  Further, as defined in the ninth aspect of the invention, the box self-supporting leg portion 95 is provided on either or both of the fixed sealing portion 74 and the easy opening portion 73. In the figure, four box self-supporting leg portions 95 (cut-in leg pieces) are provided at the fixed sealing portion 74 side by punching out with a notch 96. The box self-supporting leg 95 is convenient when the boxed automatic ventilation packaging bag storage box 7 is raised (see FIG. 15). The box self-supporting leg portions 95 are provided at four places, and the weight of the automatic ventilation packaging bag including the contents is added, so that stability is improved. A broken line in FIG. 14 indicates a fold portion 90 of the automatic ventilation packaging bag storage box 7, and each portion is bent according to the fold portion 90. The adhesive margin 79 is extended to the box lower surface portion 76, bent, and adhered to the box side surface portion 77 with an adhesive or the like. Therefore, a box shape is completed by each surface portion.

  FIG. 15 is an overall perspective view assuming the time of selling the automatic ventilation packaging bag storage box 7 (with the automatic ventilation packaging bag 1 already stored) of the present invention. The automatic ventilation packaging bag 1 is a food packaging material to be heated by a microwave oven, and is displayed in a food store of a retail store. In this case, many vertical arrangements have been proposed because of the size of the display shelves and the number of displays. Therefore, in consideration of the appearance when arranged on the display shelf, the appeal to the consumer, the atmosphere of the sales floor, etc., the automatic ventilation packaging bag storage box 7 is shown as shown in the figure rather than the display of the automatic ventilation packaging bag 1 alone. It is often displayed after being housed inside. In particular, since the higher value-added products are required to have more beautiful packaging, the role of the automatic ventilation packaging bag storage box 7 is greater.

  Therefore, the box upper surface portion 75, the box lower surface portion 76, and the box side surface portion 77 of the automatic ventilation packaging bag storage box 7, as well as the concave edge 81, the arc-shaped edge 83, the convex edge 85, etc. A display 97 of contents, producers, sellers, raw materials, and other necessary items is printed. Since the storage box has many planar portions, the display 97 can be enlarged. Therefore, the display content can be enhanced to further enhance the appeal effect of the product. In addition, since the box self-supporting leg portion 95 (cutting leg piece) is provided, the stability when placed on the display shelf is also improved. In order to prevent easy opening during distribution, a protective seal 98 is affixed to the concave edge 81 and the arc-shaped edge 83.

  16 and 17 are schematic views showing a state where the automatic ventilation packaging bag 1 (with the contents filled) is heated in the microwave while being accommodated in the automatic ventilation packaging bag storage box 7. The protective seal 98 is previously removed from the opening opening 71 (easy opening 73). Thereafter, the automatic ventilation packaging bag starts to expand due to water vapor generated from the food in the automatic ventilation packaging bag 1 with heating. Then, the box upper surface part 75 and the box lower surface part 76 are pressed from the inside of the storage box and start to deform. Therefore, as shown in FIG. 16, the concave edge 81 and the arc-shaped edge 83 are not deeply bite, so that the bulging portion 84 can be easily detached from the retreating portion 82.

  Further, as the heating proceeds, the amount of water vapor in the automatic ventilation packaging bag 1 increases, and the automatic ventilation packaging bag 1 expands more. As a result, as shown in FIG. 17, the concave edge 81 and the arc-shaped edge 83 of the storage box are completely opened in conformity to the expansion and deformation of the automatic ventilated packaging bag 1, and the opening 71 is formed without resistance. . For this reason, the expansion | swelling of the automatic ventilation packaging bag 1 is not inhibited, and the water vapor spouted from the automatic ventilation part 20 of the automatic ventilation packaging bag 1 is not exhausted into the automatic ventilation packaging bag storage box 7 and is smoothly exhausted. In particular, the rigidity of the storage box is changed by the upper surface easily bent portion 92 and the lower surface easily bent portion 91, the box upper surface portion 75 and the box lower surface portion 76 are easily bent, and the opening opening 71 is formed quickly.

  As described above, the automatic ventilation packaging bag 1 of the present invention can be arranged regardless of the upper and lower sides. And it does not ask | require which of the automatic ventilation packaging bag accommodation box 7 which accommodates the said automatic ventilation packaging bag 1 makes up and down. That is, the user can simply place it in the microwave oven without being aware of the top and bottom of the packaging bag or the storage box, and does not involve any attention or inconvenience. Therefore, rupture due to carelessness of the conventional placement is avoided and safety is improved.

[Create automatic ventilation packaging bags]
The inventor processed a heat-sealing resin film compatible with retort heating, and actually created an automatic ventilation packaging bag having the same shape as shown in the figure. The automatic ventilated packaging bag has a length (Dl) of 180 mm and a width (Ds) of 140 mm. The width of the planned ventilation portion is 18 mm, and the heat seal width is 1 mm. As shown in FIGS. 10 to 12, after the bag was made from the film by heat sealing and cutting, about 200 g of cooked curry was filled in the automatic ventilation packaging bag as a food example, and the opening was heat sealed. Then, it was carried into the retort kettle and subjected to high-pressure heat sterilization under general sterilization conditions.

[Creation of automatic ventilation packaging bag storage box]
In addition to this, an automatic ventilation packaging bag storage box for storing the automatic ventilation packaging bag was also prepared from cardboard according to the development of FIG. The storage box has a height (Dl) of 180 mm, a width (Ds) of 140 mm, and a height (Dh) of 25 mm. The bulging portion of the arcuate edge has a width of 70 mm and a bulging amount of a maximum of 4 mm. Moreover, both the upper surface easily bent part and the lower surface easily bent part are 50 mm.

[Heating of automatic ventilation packaging bags]
It was verified that the automatic ventilation packaging bag expanded properly by heating with a microwave oven and exhausted water vapor from the automatic ventilation part. The result is a photograph of FIG. FIG. 18A shows a state where the food-filled automatic ventilation packaging bag is placed at a predetermined position (on the turntable) in the home microwave oven. At this time, it is in an unheated state. In the figure, an output of 700 W and a heating condition of 1 minute were set. FIG. 5B shows a state in which the automatic ventilation packaging bag is inflated by water vapor generated from the food after about 50 seconds have passed since the heating. This time is the maximum expansion amount. Due to the expansion deformation, the pocket part of the automatic ventilation part is warped upward. FIG. 6C shows a state in which the heat seal of the planned ventilation portion is broken by the water vapor pressure and the internal water vapor is exhausted through the planned ventilation portion. The passage of water vapor can be confirmed because the pocket portion is white.

[Heating for each automatic ventilation packaging bag storage box]
The inventor who verified the effect of the automatic ventilation packaging bag accommodated the automatic ventilation packaging bag in the automatic ventilation packaging bag storage box, and tried heating the entire automatic ventilation packaging bag storage box with a microwave oven. The result is a photograph of FIG. FIG. 19A shows a state in which the automatic ventilation packaging bag is accommodated in the automatic ventilation packaging bag storage box and placed at a predetermined position (on the turntable) in the home microwave oven. At this time, it is in an unheated state. In the figure, the heating condition was set to 700 W and 1 minute and 30 seconds. The heating time was extended by taking into account the attenuation of microwaves by the storage box. FIG. 2B shows a state where the automatic ventilation packaging bag is expanded by water vapor generated from the food after about 1 minute has passed from the heating. Corresponding to the expansion deformation of the automatic ventilation packaging bag, the automatic ventilation packaging bag storage box is also deformed, and the easy-opening portion is unsealed and the opening opening portion is opened. FIG. 6C shows a state where the internal water vapor is exhausted through the planned ventilation portion. The opening opening of the storage box is kept open.

〔Results and discussion〕
As a result of the demonstration experiment disclosed in the photograph, it was confirmed that the automatic ventilated packaging bag having the structure of the present invention can be heated by the microwave oven. Also, the automatic ventilated packaging bag storage box can be deformed corresponding to the expansion of the automatic ventilated packaging bag, and the opening of the opening opening is smooth, so that the expansion of the automatic ventilated packaging bag inside is not suppressed. In addition, although food was ejected from the automatic ventilation packaging bag with a very small amount of water vapor, it could be completely received in the pocket portion and no leakage from the exhaust portion occurred. For this reason, the effect of preventing fouling inside the microwave oven was also confirmed. Therefore, it is possible to simultaneously propose a highly convenient automatic ventilation packaging bag and an automatic ventilation packaging bag storage box regardless of the vertical orientation without using an easy peel resin as in the existing automatic ventilation bags.

DESCRIPTION OF SYMBOLS 1 Automatic ventilation packaging bag 7 Automatic ventilation packaging bag storage box 10 Bag-shaped main body 10i The inside of a bag-shaped main body 11 Upper surface part 12 Lower surface part 13 Middle part 14 Bag bottom part 15 Opening part 20 Automatic ventilation part 21 1st edge part 22 2nd edge Part 23 3rd side part 24 4th side part 25 5th side part 26 6th side part 32 Side heat seal part 34 Folding fixing part 35 Upper heat seal part 36 Lower heat seal part 41 Upper inclined heat seal part 42 Lower inclination Heat sealing part 51 Intermediate heat sealing part 52 Planned ventilation part 53 Pocket part 54 Cylindrical part 55 Exhaust part 56 Incomplete sealing part 57 Medium width narrow heat sealing part 70 Box opening part 73 Easy opening part 74 Fixed sealing part 75 Box Upper surface portion 76 Box lower surface portion 77 Box side surface portion 81 Concave edge portion 82 Recessed portion 83 Arc-shaped edge portion 84 Swelling portion 87 Starting point of retracting portion 88 Starting point of bulging portion 91 Men'eki bent portion (bent auxiliary line)
92 Upper surface easy-bending part (bending auxiliary line)
95 Box Standing Leg (Incision Leg)
F Film body C Contents (food)
Cp Center part of bag-shaped body W1 Heat seal width of intermediate heat seal part W2 Heat seal width of planned ventilation part W3 Heat seal width of narrow medium heat seal part Dl Vertical direction of automatic ventilation packaging bag and automatic ventilation packaging bag storage box (Length direction)
Ds Horizontal direction (width direction) of automatic ventilation packaging bag and automatic ventilation packaging bag storage box
Dh Height direction of automatic ventilation packaging bag and automatic ventilation packaging bag storage box

Claims (9)

Consists of a film body, comprising a bag bottom and an opening to constitute a bag-shaped main body, and provided with an intermediate portion having an automatic ventilation portion between the upper surface portion and the lower surface portion of the bag-shaped main body,
In the bag bottom portion, the upper surface portion is provided with a first side portion, and the lower surface portion is provided with a sixth side portion, a second side portion, a third side portion between the first side portion and the sixth side portion, It is provided in the order of the fourth side and the fifth side,
The intermediate portion folds the second side portion, the third side portion, the fourth side portion, and the fifth side portion into a W-shape in a sectional view, and the third side portion and the fourth side portion are Formed in a direction protruding from the center of the bag-shaped main body toward the bag bottom,
It is a packaging bag in which the heat seal surfaces of the respective side portions of the upper surface portion and the lower surface portion are heat sealed as side heat seal portions,
The automatic ventilation part is an intermediate heat seal part in which the third side part and the fourth side part of the intermediate part are heat-sealed in a band shape in the lateral direction of the bag-like main body,
The intermediate heat seal portion is arranged at the center in the lateral direction and is connected to the intermediate heat seal portion, and is narrower than the heat seal width of the intermediate heat seal portion, and the bag-like body than the intermediate heat seal portion. An aeration planned portion in which the third side portion and the fourth side portion are heat-sealed by projecting in an arc shape toward the center side of
The intermediate heat seal part is connected to the intermediate heat seal part and the planned ventilation part by folding the third side part and the fourth side part shorter than the heat seal length in the lateral direction of the intermediate heat seal part. A cylindrical portion formed in parallel with each other, and a pocket portion having an exhaust portion for exhausting water vapor that has passed through the planned ventilation portion to the outside at both ends of the cylindrical portion,
An upper heat seal portion heat-sealed by projecting a lateral central portion of the first side portion and the second side portion from a bag bottom side of the bag-like main body toward a center portion side of the bag-like main body;
A lower heat seal portion is provided that heat seals by projecting a lateral center portion of the fifth side portion and the sixth side portion from a bag bottom side of the bag-like body toward a center portion side of the bag-like body. ,
An upper inclined heat seal portion that is heat-sealed in an inclined manner from the upper heat seal end portion on both the left and right sides of the upper heat seal portion to the side heat seal portion is provided,
A lower inclined heat seal portion that is heat-sealed in an inclined manner from the lower heat seal end portions on both the left and right sides of the lower heat seal portion to the side heat seal portion is provided,
An automatic ventilated packaging bag, wherein the packaging bag is placed in a microwave oven in a laid state, and the packaging bag is heated . Consists of a film body, comprising a bag bottom and an opening to constitute a bag-shaped main body, and provided with an intermediate portion having an automatic ventilation portion between the upper surface portion and the lower surface portion of the bag-shaped main body,
In the bag bottom portion, the upper surface portion is provided with a first side portion, and the lower surface portion is provided with a sixth side portion, a second side portion, a third side portion between the first side portion and the sixth side portion, It is provided in the order of the fourth side and the fifth side,
The intermediate portion folds the second side portion, the third side portion, the fourth side portion, and the fifth side portion into a W-shape in a sectional view, and the third side portion and the fourth side portion are Formed in a direction protruding from the center of the bag-shaped main body toward the bag bottom,
It is a packaging bag in which the heat seal surfaces of the respective side portions of the upper surface portion and the lower surface portion are heat sealed as side heat seal portions,
The automatic ventilation part is an intermediate heat seal part in which the third side part and the fourth side part of the intermediate part are heat-sealed in a band shape in the lateral direction of the bag-like main body,
The intermediate heat seal portion is arranged at the center in the lateral direction and is connected to the intermediate heat seal portion, and is narrower than the heat seal width of the intermediate heat seal portion, and the bag-like body than the intermediate heat seal portion. An aeration planned portion in which the third side portion and the fourth side portion are heat-sealed by projecting in an arc shape toward the center side of
The intermediate heat seal part is connected to the intermediate heat seal part and the planned ventilation part by folding the third side part and the fourth side part shorter than the heat seal length in the lateral direction of the intermediate heat seal part. A cylindrical portion formed in parallel with each other, and a pocket portion having an exhaust portion for exhausting water vapor that has passed through the planned ventilation portion to the outside at both ends of the cylindrical portion,
An upper heat seal portion heat-sealed by projecting a lateral central portion of the first side portion and the second side portion from a bag bottom side of the bag-like main body toward a center portion side of the bag-like main body;
A lower heat seal portion is provided that heat seals by projecting a lateral center portion of the fifth side portion and the sixth side portion from a bag bottom side of the bag-like body toward a center portion side of the bag-like body. ,
An upper inclined heat seal portion that is heat-sealed in an inclined manner from the upper heat seal end portion on both the left and right sides of the upper heat seal portion to the side heat seal portion is provided,
A lower inclined heat seal portion that is heat-sealed in an inclined manner from the lower heat seal end portions on both the left and right sides of the lower heat seal portion to the side heat seal portion is provided,
The upper heat seal end portion is formed as a narrow portion, and the heat seal amount of the narrow portion of the upper heat seal end portion is formed less than the heat seal amount of the central portion of the upper heat seal portion,
The lower heat seal end portion is formed as a narrow portion, and the heat seal amount of the narrow portion of the lower heat seal end portion is formed smaller than the heat seal amount of the central portion of the lower heat seal portion. And
The packaging bag is laid down and placed in a microwave oven, and the packaging bag is heated.
Automatic ventilation packaging bag characterized by that. The automatic ventilation packaging bag according to claim 1 or 2 , wherein a belt-like heat sealing width of the intermediate heat sealing portion decreases from the side portion side to the ventilation target portion. The automatic ventilation packaging bag according to any one of claims 1 to 3, wherein an incompletely sealed portion formed by heat sealing the exhaust portion is provided. In any one of to heat seal surfaces of the intermediate heat-sealed portion lateral end portions the sixth side portion of the film body and the first side portion in the vicinity of the claims 1 and is heat sealed 4 Automatic ventilation packaging bag as described.   The automatic ventilation packaging bag according to any one of claims 1 to 5, wherein the upper surface portion, the lower surface portion, and the intermediate portion are formed by bending a single film body. A rectangular parallelepiped storage box for storing the automatic ventilation packaging bag according to any one of claims 1 to 6,
Box openings of the storage box are provided opposite to each other, one of the box openings is sealed by an easy opening portion and the other is sealed by a fixed sealing portion,
The easy-opening portion extends from the bottom surface of the box with a concave edge having a concave shape in plan view, with a receding portion provided in the center in the lateral direction of the easy-opening portion, and at the center in the width direction of the easy-opening portion An arcuate edge having a convex shape in plan view provided with an arcuate bulging portion that penetrates the receding portion is provided to extend to the upper surface portion of the box,
The automatic ventilation packaging bag storage box, wherein the automatic ventilation portion of the automatic ventilation packaging bag is disposed and accommodated on the easy-opening portion side.   The lower surface easily bent portion that extends from the starting point of the receding portion to the lower surface portion of the box and the upper surface easily bent portion that extends from the starting point of the bulging portion to the upper surface portion of the box are provided in the easy opening portion. Automatic ventilation packaging bag storage box as described.   The automatic ventilation packaging bag storage box according to claim 7 or 8, wherein a box self-supporting leg portion is provided in either or both of the fixed sealing portion and the easy-opening portion.

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