Packaging bags and display methods

Abstract

To provide a packaging bag and display method that can stand upright stably when displayed. [Solution] A packaging bag according to one embodiment comprises a bag body having a surface film portion and a back film portion, and a flap having a first side film portion and a second side film portion, connected to the back film portion. The bag body has a first tip portion and a second tip portion, the first tip portion having a first seal portion, the flap tip portion located opposite the connecting portion of the flap having a second seal portion, the flap being provided with a zipper tape, a part of the zipper tape having a steam vent portion for releasing steam, the length from the connecting portion to the flap tip portion being less than or equal to the length from the connecting portion to the first tip portion, and the surface film portion being provided with a guidance information display portion that, when viewed from the surface film portion side, displays information that guides the packaging bag to be positioned with the first tip portion facing downwards when displayed.

Description

Technical Field

[0001] The present invention relates to a packaging bag and a display method.

Background Art

[0002] There is a package described in Patent Document 1 as a packaging bag for cooking by heating in a microwave oven. The package described in Patent Document 1 has a peripheral seal portion where three sides of two package films are sealed, and a chuck tape is provided on the remaining one side. With such a configuration, a consumer can put contents such as food ingredients into the packaging bag from the chuck tape and seal it. After heating and cooking, the consumer can also take out the contents such as food ingredients from the chuck tape. In the package described in Patent Document 1, a clasp seal portion is formed on the two package films so as to protrude outward from the package. The clasp seal portion is formed so as to have an easy-opening property of releasing the pressure when the internal pressure of the package rises during heating and cooking.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the packaging (packaging bag) described in Patent Document 1, the zipper tape and the gusset seal are located towards the top. When the contents are placed inside the packaging, they are located below the zipper tape and the gusset seal. Therefore, if the packaging is displayed upright, the zipper tape and the gusset seal are located above the surface on which the packaging is placed on the display shelf, etc. In this case, the top of the displayed packaging may bend, causing the top of the packaging to droop. When the top of the packaging droops in this way, consumers may not be able to properly read the product information printed on the packaging, and the product image may be diminished.

[0005] Therefore, one objective of the present invention is to provide a packaging bag and display method that can stand upright stably when displayed. [Means for solving the problem]

[0006] [1] A packaging bag according to one aspect of the present invention is a packaging bag for containing contents to be heated in a microwave oven, and comprises a bag body containing the contents, and a flap having an opposing first side film portion and a second side film portion, which is connected to the back film portion, wherein the bag body has a first tip portion and a second tip portion which are opposite to each other with respect to the connection portion with the flap, and a first seal portion is formed on the first tip portion, and the back film portion has a first back film portion which is the portion between the connection portion and the first tip portion, and a second back film portion which is the portion between the connection portion and the second tip portion, and the first side film The 'mu' portion is connected to the first back film portion, the second side film portion is connected to the second back film portion, a second seal portion is formed at the tip of the flap opposite to the connecting portion on the flap, a zipper tape is provided on the flap between the second seal portion and the connecting portion, a steam vent portion is formed in a part of the zipper tape for releasing steam, the length from the connecting portion to the tip of the flap is less than or equal to the length from the connecting portion to the first tip portion, and the surface film portion is provided with a guidance information display portion that, when viewed from the surface film portion side, displays information that guides the packaging bag to be positioned with the first tip portion facing downwards when displayed.

[0007] In the above-mentioned packaging bag, for example, when sold in a retail store, the flap with the zipper tape is displayed facing downwards, allowing the packaging bag to stand upright stably.

[0008] [2] In the packaging bag described in [1] above, when the first tip and the tip of the flap are in contact with the mounting surface and the packaging bag is placed upright on the mounting surface such that the angle between the flap and the mounting surface is greater than 45 degrees and less than 90 degrees, the angle between the flap and the bag body may be 10 degrees or more and 15 degrees or less. Such a packaging bag is more stable when it is placed upright.

[0009] [3] In the packaging bag described in [1] or [2] above, the first loop stiffness values ​​of the first seal portion and the second seal portion are 400 mN or more, and the second loop stiffness value of a predetermined portion of the flap other than the first seal portion and the second seal portion is 3000 mN or more, and the first loop stiffness value and the second loop stiffness value may be values ​​measured under measurement conditions in which the sample width is 10 mm, the loop length is 80 mm, and the compression distance is 10 mm. Such a packaging bag will be more stable when it is made to stand on its own.

[0010] [4] In the packaging bag described in [3] above, the flap is provided with a watertight sealing portion between the zipper tape and the connecting portion for separating the zipper tape from the bag body, and the predetermined portion may be the zipper tape or the watertight sealing portion.

[0011] [5] In the packaging bag described in any of [1] to [4] above, the ratio of the length from the connecting portion to the first tip to the length from the connecting portion to the tip of the flap may be 0.9 or more and 1.0 or less.

[0012] [6] In the packaging bag described in any of [1] to [5] above, the ratio of the length of the bag body in the direction perpendicular to the connecting portion to the length of the bag body in the direction along the connecting portion is 0.5 or more and 1.0 or less.

[0013] [7] Another aspect of the present invention relates to a display method for displaying packaging bags containing contents to be heated in a microwave oven on a display surface. The packaging bag has opposing front film portions and back film portions, and comprises a bag body containing the contents, and a flap having opposing first side film portions and second side film portions, connected to the back film portion, the bag body having a first tip portion and a second tip portion located opposite each other with respect to the connection portion with the flap, the first tip portion having a first seal portion, the back film portion having a first back film portion which is the portion between the connection portion and the first tip portion, and a second back film portion which is the portion between the connection portion and the second tip portion, and the first side film portion is connected to the first back film portion. The second side film portion is connected to the second back film portion, a second seal portion is formed at the tip of the flap opposite to the connecting portion, a zipper tape is provided on the flap between the second seal portion and the connecting portion, a steam vent portion is formed on a part of the zipper tape for releasing steam, the length from the connecting portion to the tip of the flap is less than or equal to the length from the connecting portion to the first tip, and the surface film portion is provided with a guidance information display portion that, when viewed from the surface film portion side, displays information that guides the packaging bag to be positioned with the first tip facing downwards when it is displayed. In the above display method, the packaging bag is placed on the above-described display surface so that the first tip and the tip of the flap are in contact with the above-described display surface.

[0014] In this display method, for example, when sold in a retail store, the packaging bags are displayed with the flap containing the zipper tape facing downwards, allowing them to stand upright stably.

[0015] [8] In the display method according to [7] above, the packaging bag may be placed on the placement surface such that the angle between the flap and the placement surface is greater than 45 degrees and less than 90 degrees, and the angle between the flap and the bag body is 10 degrees or more and 15 degrees or less. In this case, it is easier to maintain a more stable self-standing state when displaying the packaging bag.

Effects of the Invention

[0016] According to the present invention, it is possible to provide a packaging bag that can stand stably during display and a display method.

Brief Description of the Drawings

[0017] [Figure 1] FIG. 1 is a drawing showing a state where a packaging bag according to an embodiment is displayed on a placement surface. [Figure 2] FIG. 2 is a plan view of the packaging bag shown in FIG. 1 when viewed from the front side. [Figure 3] FIG. 3 is a plan view of the packaging bag shown in FIG. 1 when viewed from the back side. [Figure 4] FIG. 4 is a drawing of the packaging bag shown in FIG. 3 with a part of the flap (branch portion) of the packaging bag cut out. [Figure 5] FIG. 5 is a drawing for explaining the chuck tape and the watertight seal portion. [Figure 6] FIG. 6 is a schematic diagram showing an example of the configuration of the film forming the packaging bag shown in FIG. 1. [Figure 7] FIG. 7 is a schematic diagram of the self-standing packaging bag on the placement surface when viewed from the side. [Figure 8] FIG. 8 is a drawing for explaining an intermediate manufactured in an intermediate manufacturing process of the manufacturing method of the packaging bag shown in FIG. 1. [Figure 9] FIG. 9 is a plan view of the intermediate shown in FIG. 8. [Figure 10] FIG. 10 is a drawing for explaining a vent hole forming process of the manufacturing method of the packaging bag shown in FIG. 1. [Figure 11]FIG. 11 is a drawing for explaining a side edge sealing step included in the method for manufacturing the packaging bag shown in FIG. 1. [Figure 12] FIG. 12 is a drawing for explaining a folding step included in the method for manufacturing the packaging bag shown in FIG. 1. [Figure 13] FIG. 13 is a plan view of the packaging bag manufactured through the folding step. [Figure 14] FIG. 14 is a drawing for explaining a bending step included in the intermediate manufacturing step for manufacturing the intermediate shown in FIG. 8. [Figure 15] FIG. 15 is a drawing for explaining a third tip sealing step included in the intermediate manufacturing step for manufacturing the intermediate shown in FIG. 8. [Figure 16] FIG. 16 is a drawing for explaining a first tip opening step and a second tip opening step included in the intermediate manufacturing step for manufacturing the intermediate shown in FIG. 8. [Figure 17] FIG. 17 is a drawing for explaining a chuck tape attachment step included in the intermediate manufacturing step for manufacturing the intermediate shown in FIG. 8. [Figure 18] FIG. 18 is a drawing for explaining a watertight seal part forming step included in the intermediate manufacturing step for manufacturing the intermediate shown in FIG. 8. [Figure 19] FIG. 19 is a chart showing the dimensions of the packaging bags of Experimental Examples 1 to 4. [Figure 20] FIG. 20 is a chart showing the experimental results of Experimental Examples 1 to 4.

Embodiments for Carrying Out the Invention

[0018] Hereinafter, embodiments of the present invention will be described while referring to the drawings. The same elements are denoted by the same reference numerals. Redundant explanations are omitted. The dimensional ratios in the drawings do not necessarily match those in the description.

[0019] The packaging bag according to this embodiment is a packaging bag for heating and cooking the contents it contains in a microwave oven. Hereinafter, unless otherwise specified, the side of the packaging bag that faces the consumer (hereinafter sometimes referred to as "user") when displayed in a store or elsewhere will be referred to as the front or front surface, and the side opposite the front will be referred to as the back surface.

[0020] Figure 1 is a diagram showing the packaging bag 1 according to this embodiment displayed on a mounting surface P. Figure 2 is a plan view of the packaging bag 1 shown in Figure 1 as seen from the front. Figure 3 is a plan view of the packaging bag 1 shown in Figure 1 as seen from the back. Figure 4 is a diagram of the packaging bag 1 shown in Figure 3 with a portion of the flap 20 of the packaging bag 1 cut out. Figures 2 and 3 show the state in which the flap 20 of the packaging bag 1 is folded toward the first body portion 11A of the bag body 10 of the packaging bag 1.

[0021] As shown in Figure 1, the packaging bag 1 of this embodiment contains contents 2, which are part of the food to be cooked, when it is displayed on the shelf surface P of a retail store or the like. An example of contents 2 is a cooking seasoning liquid. The food to be cooked is made by adding additional contents to contents 2. Additional contents may include ingredients such as fish or meat. Additional contents may also include raw eggs, vegetables, etc.

[0022] A consumer who purchases packaging bag 1 places additional contents (or ingredients) that constitute the contents to be heated together with contents 2 into packaging bag 1. The consumer then heats the contents 2 and additional contents in a microwave oven.

[0023] The packaging bag 1 shown in Figures 1 to 4 is manufactured by forming a bag using the film F shown in Figure 6. The film F used in the packaging bag 1 will be explained using Figure 6. Figure 6 is a diagram illustrating an example of the film F that forms the packaging bag 1.

[0024] [film] Film F is a laminated film having a sealant layer F1 and a resin substrate layer F2 laminated on the sealant layer F1. In film F, the side opposite to the resin substrate layer F2 is the side that constitutes the inner surface of the packaging bag 1 and is a heat-sealable surface.

[0025] Examples of materials for the sealant layer F1 include thermoplastic resins, such as polyolefin resins. Examples of materials for the sealant layer F1 include low-density polyethylene resin (LDPE), medium-density polyethylene resin (MDPE), and linear low-density polyethylene resin (LLDPE).

[0026] The sealant layer F1 can be made from an ethylene-based resin, a polypropylene-based resin, or a blend of polyethylene and polypropylene. Examples of ethylene-based resins include ethylene-vinyl acetate copolymer (EVA), ethylene-α-olefin copolymer, and ethylene-methacrylic acid resin copolymer. Examples of polypropylene-based resins include homopolypropylene resin (PP), propylene-ethylene random copolymer, propylene-ethylene block copolymer, and propylene-α-olefin copolymer. For example, an unoriented polypropylene (CPP) film can be used for the sealant layer F1.

[0027] A plastic film can be used as the resin base layer F2. Examples of materials for the resin base layer F2 include polyolefins, polyesters, polyamides, and polyimides. Examples of polyolefins include polyethylene (PE) and polypropylene (PP). Examples of polyesters include polyethylene terephthalate (PET), polybutylene terephthalate (PBT), and polyethylene naphthalate (PEN). Examples of polyamides include nylon-6 and nylon-66. The material for the resin base layer F2 is appropriately selected according to the application of the packaging bag 1. A uniaxially or biaxially stretched plastic film may be used for the resin base layer F2.

[0028] When the resin substrate layer F2 is made of polypropylene or polyethylene terephthalate, it is more preferable in terms of film strength and cost. When a stretched polyamide film is used as the resin substrate layer F2, the film F can be given toughness against punctures and impacts.

[0029] The film F has a printed layer F3. The printed layer F3 is a layer on which images for enhancing the product's image, necessary information about the contents 2, etc., are printed. In the example shown in Figure 6, the printed layer F3 is positioned between the sealant layer F1 and the resin substrate layer F2, but the printed layer F3 can be provided in a position on the film F that is visible from the outside of the packaging bag 1. The printed layer F3 may also be provided in a position on the film F that is the outermost surface of the packaging bag 1. The printed layer F3 may be provided in a portion of the film F corresponding to a part of the packaging bag 1, or it may be provided in the entire film F.

[0030] There are no particular restrictions on the printing method and printing ink used to form the printed layer F3. The above-mentioned printing method and printing ink should be selected from known printing methods, taking into consideration factors such as suitability for printing on the layer to which the printed layer is to be formed, design aspects such as color tone, adhesion, and safety as a food packaging bag.

[0031] Examples of the printing methods mentioned above include gravure printing, offset printing, gravure-offset printing, flexographic printing, screen printing, and inkjet printing.

[0032] Film F may have layers other than the sealant layer F1, the resin substrate layer F2, and the printing layer F3. For example, to improve the shelf life of a portion of the contents to be heated in a microwave oven (contents 2 described later), film F may have an opaque layer that blocks ultraviolet rays, such as a colored film. Film F may have a gas barrier layer. Film F may have a gas barrier film formed by providing a gas barrier layer on the surface of a plastic film.

[0033] If film F has the above-mentioned gas barrier film, the plastic film of the gas barrier film may be a film formed from a polymer resin composition. Examples of materials for the plastic film of the gas barrier film include polyolefins (polyethylene, polypropylene, etc.), polyesters (polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, etc.), polyamides (nylon-6, nylon-66, etc.), and polyimides, which can be appropriately selected depending on the application. When polypropylene, polyethylene terephthalate, etc. are used as the material for the plastic film of the gas barrier film, they are more preferable in terms of film strength and cost.

[0034] The gas barrier layer of a gas barrier film can be composed of a vapor-deposited layer of an inorganic compound, a layer applied by a wet coating method, and so on. For example, a gas barrier film can be obtained by first applying an anchor coat layer to a plastic film, and then sequentially applying a vapor-deposited layer and a wet coating layer.

[0035] For the anchor coat layer, for example, urethane acrylate can be used. The anchor coat layer can be formed by dissolving a resin in a solvent and using a coating method that applies printing techniques such as gravure coating to form a coating film, or by using other generally known coating methods.

[0036] One method for forming the above-mentioned vapor-deposited layer is to coat an inorganic compound such as SiO2 or Al2O3 onto a plastic film constituting the gas barrier film using a vacuum deposition method. The thickness of the vapor-deposited layer may be 15 nm or more and 30 nm or less.

[0037] An inorganic compound layer (hereinafter referred to as the "second inorganic compound layer") may be formed on top of the inorganic compound layer (hereinafter referred to as the "first inorganic compound layer") formed by the vacuum deposition method described above by a wet coating method. In this way, the laminate formed by the first inorganic compound layer and the second inorganic compound layer may be used as a gas barrier layer.

[0038] When a gas barrier layer is formed by stacking a first inorganic compound layer and a second inorganic compound layer, a reaction layer is created at the interface between the first and second inorganic compound layers, or a dense structure is formed by the second inorganic compound layer filling or reinforcing defects or micropores such as pinholes, cracks, grain boundaries that occur in the first inorganic compound layer.

[0039] Therefore, it achieves higher gas barrier properties, moisture resistance, and water resistance as a gas barrier film, and also possesses flexibility to withstand deformation due to external forces, thus making it suitable as a packaging material.

[0040] When SiO2 is used as the gas barrier layer, for example, the coating is transparent, making it possible to visually inspect the contents from the outside of the packaging bag 1. These can be used appropriately depending on the application and required quality. By leaving a portion of the film F without a printed layer, it is also possible to use that portion as a window.

[0041] Each layer of film F may be joined together using an adhesive, a plastic layer for extruder lamination, or other methods known in the art.

[0042] Next, an example of the configuration of the packaging bag 1 using film F will be explained using Figures 1 to 4. In the following explanation, the X and Y directions shown in Figure 2 may be used. The X direction corresponds to the width direction when the packaging bag 1 is viewed from the front (or back) side, and the Y direction corresponds to the direction perpendicular to the width direction when the packaging bag 1 is viewed from the front (or back) side in plan view. [Packaging bag] The packaging bag 1 has a bag body 10 having a storage space for contents 2 to be heated in a microwave oven, and a flap 20 connected to the bag body 10. The flap 20 is connected to the back side of the bag body 10. The flap 20 is a branched part that branches off from the bag body 10 and is also referred to as a fin. The length L1 (mm) of the packaging bag 1 in the Y direction is 180 mm or more and 230 mm or less. An example of the length L2 (mm) of the packaging bag 1 in the X direction is 150 mm or more and 200 mm or less. <Bag body> The bag body 10 has a first tip 10a and a second tip 10b. The first tip 10a and the second tip 10b extend in the X direction. The first tip 10a is located on the lower side when the packaging bag 1 is displayed (sold) and is the part that contacts the mounting surface P. The second tip 10b is located on the upper side when the packaging bag 1 is displayed (sold). The bag body 10 has a pair of side edges 10c and 10d that connect the first tip 10a and the second tip 10b. The side edges 10c and 10d extend in the Y direction.

[0043] In this embodiment, the periphery of the bag body 10 is sealed. Specifically, the first tip portion 10a and the second tip portion 10b are heat-sealed. As a result, sealing portions (first sealing portion) 10Sa and sealing portion 10Sb are formed on the first tip portion 10a and the second tip portion 10b. The side edges 10c and side edges 10d are heat-sealed. As a result, sealing portions 10Sc and sealing portion 10Sd are formed on the side edges 10c and side edges 10d.

[0044] An example of the seal width of seal portion 10Sa is 8 mm or more and 12 mm or less. An example of the seal width of seal portion 10Sb is 8 mm or more and 15 mm or less. An example of the seal width of seal portion 10Sc and seal portion 10Sd is 8 mm or more and 12 mm or less. In this embodiment, the seal width is the length in the direction perpendicular to the extending direction of the seal portion.

[0045] The bag body 10 has a front film portion 111 and a back film portion 112. The front film portion 111 and the back film portion 112 are made of film F. The front film portion 111 and the back film portion 112 are arranged so that their sealant layers F1 face each other. The periphery of the front film portion 111 and the back film portion 112 is sealed. In this embodiment, the periphery of the front film portion 111 and the back film portion 112 is heat-sealed. This forms the sealed portions 10Sa, 10Sb, 10Sc, and 10Sd.

[0046] As mentioned above, a flap 20 is attached to the back of the bag body 10. For the sake of explanation, the portion of the bag body 10 between the connection portion 3 with the flap 20 and the first tip portion 10a will be referred to as the first body portion 11A, and the portion between the connection portion 3 and the second tip portion 10b will be referred to as the second body portion 11B. Furthermore, the portions of the surface film portion 111 that constitute the first body portion 11A and the second body portion 11B will be referred to as the first surface film portion 111A and the second surface film portion 111B, and the portions of the back film portion 112 that constitute the first body portion 11A and the second body portion 11B will be referred to as the first back film portion 112A and the second back film portion 112B.

[0047] The first body portion 11A has an opening portion 12 for removing the cooked contents 2. The opening portion 12 may have an opening trigger portion 121 (see Figure 2) formed on at least one of the side edge portions 10c and 10d. The opening trigger portion 121 is a portion that indicates the opening position and is the portion that should be the starting point for opening, for example, a notch.

[0048] The opening section 12 may have an opening guide line extending in the X direction. The opening guide line is a line that supports (or guides) opening when the first body section 11A is cut open. The opening guide line only needs to be formed on at least one of the first surface film section 111A and the first back film section 112A.

[0049] An example of an opening guideline is an easy-open mechanism (or vulnerable part) that allows the first body portion 11A to be cut open with the fingers. The easy-open mechanism may be a mechanism known in the art. The easy-open mechanism may be realized, for example, by making a half-cut in at least one of the first surface film portion 111A and the first back film portion 112A, or by utilizing the molecular orientation of the film F.

[0050] If the opening section 12 is configured to break the first body section 11A by utilizing the molecular orientation of the film F, the opening section 12 may be made visible by indicating a line along the opening section 12, for example, by printing.

[0051] In the sealing portion 10Sc and sealing portion 10Sd, a linear mark (hereinafter referred to as "linear mark 13") along the X direction may be formed at the position of the first tip portion 10a when the first body portion 11A is folded back toward the second body portion 11B with the connecting portion 3 as the axis. Specifically, the linear mark 13 may be formed at a position such that the length from the linear mark 13 to the connecting portion 3 is substantially the same as the length from the connecting portion 3 to the first tip portion 10a. The linear mark 13 is a mark caused by the part corresponding to the first body portion 11A being pressed against the part corresponding to the second body portion 11B during the manufacturing process of the packaging bag 1.

[0052] <Flap> The flap 20 functions as an opening for consumers to add additional contents to the bag body 10. Together with the first body 11A, the flap 20 also functions as a support for the packaging bag 1 when it is displayed.

[0053] The flap 20 has a first side film portion 21 (see Figure 5) and a second side film portion 22. The first side film portion 21 and the second side film portion 22 are made of film F. The first side film portion 21 and the second side film portion 22 are arranged so that their sealant layers F1 face each other. The first side film portion 21 is continuously connected to the first back film portion 112A. The second side film portion 22 is continuously connected to the second back film portion 112B.

[0054] The connecting portion 3 between the flap 20 and the bag body 10 may be the part where the flap 20 is connected to the bag body 10 when the inner surfaces of the first side film portion 21 and the second side film portion 22 are in contact. The connecting portion 3 may be the part that becomes the pivot axis (or rotation axis) when the flap 20 is swung relative to the bag body 10 while the inner surfaces of the first side film portion 21 and the second side film portion 22 are in contact. For example, the center position in the X direction between the boundary line between the first side film portion 21 and the first back film portion 112A and the boundary line between the second side film portion 22 and the second back film portion 112B may be considered as the connecting portion 3.

[0055] The flap 20 has a flap tip 20a, a side edge 20b, and a side edge 20c. The flap tip 20a is the end of the flap 20 opposite to the bag body 10 and is aligned with the X direction. The side edges 20b and 20c are aligned with a direction intersecting the X direction when the flap 20 is viewed from above. In this embodiment, each of the side edges 20b and 20c is perpendicular to the extending direction of the flap tip 20a. The plan view of the flap 20 means the flap 20 viewed from the first side film portion 21 (or second side film portion 22). The plan view of the flap 20 corresponds to the flap 20 viewed from the thickness direction. The side edges 20b and 20c are a pair of side edges of the flap 20.

[0056] The flap tip 20a, side edge 20b, and side edge 20c are sealed. In this embodiment, the flap tip 20a, side edge 20b, and side edge 20c are heat-sealed. The flap 20 has a sealing portion (second sealing portion) 20Sa formed by sealing the flap tip 20a, a sealing portion 20Sb formed by sealing the side edge 20b, and a sealing portion 20Sc formed by sealing the side edge 20c.

[0057] An example of the seal width for seal portion 20Sa is 4 mm or more and 10 mm or less. An example of the seal width for seal portions 20Sb and 20Sc is 8 mm or more and 12 mm or less.

[0058] The flap 20 has an opening portion 23. The opening portion 23 is a part of the flap 20 that is to be broken in order to put additional contents into the bag body 10 from the flap 20. The opening portion 23 is located between the sealing portion 20Sa and the connecting portion 3.

[0059] The opening portion 23 may have an opening trigger portion 231 on at least one of the side edge portions 20b and 20c. The opening trigger portion 231 is a portion that indicates the opening portion 23 and is also a portion that should be the starting end for tearing (or breaking) the flap 20 to open it in order to put additional contents into the bag body 10 from the flap 20, for example, a notch.

[0060] The opening section 23 may have an opening guide line extending in the X direction. The opening guide line is a line that assists the consumer in opening the bag body 10 by tearing (or ripping) the flap 20 in order to put additional contents inside. The opening guide line only needs to be formed on at least one of the first side film section 21 and the second side film section 22.

[0061] The opening guide line is an easy-open mechanism (or vulnerable part) that allows the flap 20 to be torn open with the fingers. The easy-open mechanism may be any mechanism known in the art. The easy-open mechanism may be realized, for example, by making a half-cut in at least one of the first side film portion 21 and the second side film portion 22, or by utilizing the molecular orientation of the film F.

[0062] If the opening section 23 is configured to break the flap 20 by utilizing the molecular orientation of the film F, for example, the opening section 23 may be made visible by indicating a line along the opening section 23, for example, by printing.

[0063] The flap 20 is provided with a zipper tape 30 between the opening portion 23 and the connecting portion 3. The flap 20 may also be provided with a watertight seal portion 40 between the zipper tape 30 and the connecting portion 3. In the following, unless otherwise specified, the configuration in which the watertight seal portion 40 is provided on the flap 20 will be described.

[0064] The chuck tape 30 is provided along the X direction (the width direction of the flap 20). The chuck tape 30 is a tape having an interlocking portion 31. The interlocking portion 31 is provided between the sealing portion 20Sb and the sealing portion 20Sc. The chuck tape 30 is a tape that can be opened and closed. An example of the width of the chuck tape 30 is 12 mm or more and 18 mm or less. The width of the chuck tape 30 is the length of the chuck tape 30 in a direction perpendicular to the extending direction of the chuck tape 30.

[0065] An example of the length between the chuck tape 30 and the connecting portion 3 is 0 mm or more and 10 mm or less. The length between the chuck tape 30 and the connecting portion 3 is the length along the direction perpendicular to the extending direction of the chuck tape 30, and may be the length between the end of the chuck tape 30 closer to the connecting portion 3 and the connecting portion 3. The example of the length between the chuck tape 30 and the connecting portion 3 includes cases where the watertight seal portion 40 in the form illustrated in Figure 5 is not provided on the flap 20.

[0066] In the packaging bag 1, a steam vent 311 is provided on a portion of the zipper tape 30 to release steam generated inside the packaging bag 1 during microwave heating. The steam vent 311 is an automatic steam venting mechanism configured to automatically release steam when the pressure of the steam generated inside the packaging bag 1 reaches a predetermined pressure during the above-mentioned heating process.

[0067] The steam vent portion 311 in this embodiment is a weak occlusal portion in which the chuck function (occlusal function) is reduced so that the portion of the occlusal portion 311 corresponding to the steam vent portion 311 is easier to detach the chuck from compared to other portions. The weak occlusal portion, which is the steam vent portion 311, only needs to be configured so that when only the weak occlusal portion is cut out from the chuck tape 30, the two members constituting the weak occlusal portion (male member 32 and female member 33 shown in Figure 6) can be separated without snagging. The weak occlusal portion can be formed by crushing a part of the occlusal portion 31. The occlusal portion 31 may be crushed by, for example, heating or pressing. The steam vent portion 311 may be located in the center of the width direction (X direction) of the chuck tape 30.

[0068] The watertight seal portion 40 is the part that separates the zipper tape 30 from the storage space (internal space) of the bag body 10. In this embodiment, the watertight seal portion 40 is formed by joining a part of the watertight film 41 to the second side film portion 22. The second side film portion 22 and the watertight film 41 may be joined by sealing in a wavy pattern, for example, as shown by dashed lines in Figures 3 and 4. The wavy sealing portion shown by dashed lines in Figures 3 and 4 is referred to as the wavy seal 42.

[0069] An example of the width of the watertight seal portion 40 is 5 mm or more and 10 mm or less. The width of the chuck tape 30 is the length of the watertight seal portion 40 in the direction perpendicular to the extending direction of the watertight seal portion 40.

[0070] The watertight seal portion 40 has the function of preventing the contents 2 contained in the bag body 10 from coming into contact with the zipper tape 30 before the flap 20 is opened. This makes it less likely for the consumer's hands or fingers to get dirty when operating the zipper tape 30.

[0071] The chuck tape 30 and the watertight seal portion 40 will be further explained using Figure 5. Figure 5 is a diagram illustrating the chuck tape 30 and the watertight seal portion 40, and shows an enlarged portion of the cross-section of the flap 20 perpendicular to the extending direction of the chuck tape 30.

[0072] As shown in Figure 5, the chuck tape 30 has a strip-shaped male member (second chuck member) 32 and a strip-shaped female member (first chuck member) 33 that can interlock with the male member 32. The male member 32 and the female member 33 are made of thermoplastic resin. An example of the thermoplastic resin is polypropylene resin. As shown in Figure 5, a configuration in which the male member 32 is fixed to the inner surface of the first side film portion 21 and the female member 33 is fixed to the inner surface of the second side film portion 22 will be described. However, the male member 32 may be fixed to the inner surface of the second side film portion 22 and the female member 33 may be fixed to the inner surface of the first side film portion 21.

[0073] The male member 32 has a base 321 and an insertion portion 322. The base 321 extends in the X direction and has a film-like appearance. The length of the base 321 in the X direction may be the same as the length of the flap 20 in the X direction. The base 321 is joined to the inner surface of the first side film portion 21. The joining of the base 321 and the first side film portion 21 may be carried out, for example, by heat sealing.

[0074] The base 321 may be fixed to the first side film portion 21 by joining (e.g., heat sealing) the entire surface of the base 321 that is in contact with the first side film portion 21 to the first side film portion 21. Alternatively, the base 321 may be fixed to the first side film portion 21 by joining (e.g., heat sealing) both ends of the base 321 to the first side film portion 21 in a cross section perpendicular to the extending direction (X direction) of the base 321, as shown by the dashed lines in regions 321a and 321b in Figure 5.

[0075] The insertion portion 322 extends in the X direction, similar to the base 321. The insertion portion 322 is provided along the base 321. The length of the insertion portion 322 in the X direction may be the same as the length of the base 321 in the X direction. The insertion portion 322 has a head portion 322a that is inserted into the female member 33 and a connecting portion 322b that connects the head portion 322a to the base 321. The head portion 322a and the connecting portion 322b extend in the X direction, similar to the base 321. In a cross-section of the male member 32 perpendicular to the X direction, the head portion 322a is, for example, arrowhead-shaped. In a cross-section of the male member 32 perpendicular to the X direction, the insertion portion 322 can also be described as a protrusion that projects from the base 321 opposite to the first side film portion 21.

[0076] The female member 33 has a base 331 and a receiving portion 332. The base 331 extends in the X direction and has a film-like appearance. The length of the base 331 in the X direction is the same as that of the base 321. The base 331 is joined to the inner surface of the second side film portion 22. The joining of the base 331 and the second side film portion 22 may be carried out, for example, by heat sealing.

[0077] The base 331 may be fixed to the second side film portion 22 by joining (for example, heat sealing) the entire surface of the base 331 that is in contact with the second side film portion 22 to the second side film portion 22. The base 331 may also be fixed to the second side film portion 22 by joining (for example, heat sealing) both ends of the base 331 to the second side film portion 22 in a cross section perpendicular to the extending direction (X direction) of the base 331, as shown by the dashed lines in regions 331a and 331b in Figure 5.

[0078] The receiving portion 332 extends in the X direction, similar to the base 331. The arrangement of the receiving portion 332 relative to the base 331 and its length in the X direction are the same as the arrangement of the insertion portion 322 relative to the base 321 and its length in the X direction. The receiving portion 332 has a recess 332a into which the head portion 322a is inserted.

[0079] The head portion 322a and the receiving portion 332 (or recess 332a) only need to be configured to be able to occlude with each other. The occlusal portion 31 is formed by the head portion 322a and the receiving portion 332 (or recess 332a).

[0080] The occlusal portion 31 may satisfy the relationship shown in the following formula (A) between the occlusal strength on the inside of the occlusal portion 31 (bag body 10 side) (internal occlusal strength) and the occlusal strength on the outside of the occlusal portion 31 (flap tip 20a side) (external occlusal strength). Internal occlusal strength > external occlusal strength...(A)

[0081] An occlusal portion 31 that satisfies equation (A) can be realized by configuring the head portion 322a and the receiving portion 332 such that the cross-sectional shape of the occlusal portion 31 perpendicular to the extending direction (X direction) of the occlusal portion 31 is asymmetrical with respect to the center line 31a of the occlusal portion 31.

[0082] When the consumer opens the zipper tape 30 after the sealing portion 20Sa side of the flap 20 has been cut, the consumer spreads the flap 20 by holding the ends of the first side film portion 21 and the second side film portion 22 near the tip portion 20a of the flap. Therefore, as shown in formula (A), if the external occlusal strength is less than the internal occlusal strength, the occlusal portion 31 is easily opened. When the packaging bag 1 is heated, the zipper tape 30 is closed. During heating, the internal pressure inside the packaging bag 1 increases. As shown in formula (A), if the internal occlusal strength is greater than the external occlusal strength, even if the internal pressure of the packaging bag 1 increases, it is possible to prevent the occlusal portion 31 from being unexpectedly opened by the internal pressure. In other words, by satisfying formula (A), it is possible to ensure that the zipper tape 30 is easy to open when adding contents from the flap 20, while preventing the zipper tape 30 from being unexpectedly opened during heating.

[0083] As shown in Figure 5, one end of the watertight film 41 is fixed to the female member 33. Specifically, one end of the watertight film 41 is fixed to the end of the base 331 closer to the bag body 10. The watertight film 41 is an easy-peel film. An example of the material for the watertight film 41 is a polypropylene resin. In the watertight film 41, the end region 411, which includes the end opposite to the end fixed to the female member 33, is peelably joined to the inner surface of the first side film portion 21. The end region 411 is sealed to the first side film portion 21 in a wave-like manner, for example. In Figure 5, the area enclosed by the dashed line is schematically shown as the area for forming the wave-like seal 42.

[0084] As shown in Figure 1, the packaging bag 1 has a guidance information display section 4. The guidance information display section 4 has the function of displaying information to guide the salesperson to place the packaging bag 1 on the placement surface P so that the first tip 10a is positioned downwards, as shown in Figure 1, when the packaging bag 1 is sold. The guidance information display section 4 is provided on the surface film section 111. The guidance information display section 4 may be an image such as text or a picture, which is constructed assuming that the first tip 10a is facing downwards. The information displayed by the guidance information display section 4 may be information that reminds the consumer of the food to be cooked or the contents of the product, or a product description. The guidance information display section 4 may also be information (text, arrows, etc.) that directly indicates that the packaging bag 1 should be sold with the first tip 10a facing downwards. The guidance information display section 4 may be displayed by printing on the packaging bag 1. In this case, the surface film section 111 has a printing layer F3.

[0085] Figure 7 is a schematic diagram of the packaging bag 1 as viewed from the side when it is standing upright on the mounting surface P with the first tip portion 10a and the flap tip portion 20a facing downwards.

[0086] Figure 7 shows the origin O, U-axis, and Y-axis. The origin O is the intersection of the first tip 10a and the mounting surface P in the arrangement of the packaging bag 1. The U-axis is the axis (direction) passing through the origin O and along the mounting surface P, and the Y-axis is the axis (direction) passing through the origin O and perpendicular to the U-axis. In the following description, the position on the U-axis of the intersection of the flap tip 20a and the mounting surface P will be referred to as position Ua. Furthermore, the angle between the seal portion 10Sa and the U-axis (or mounting surface P) will be referred to as angle α(°), and the angle between the bag body 10 and the flap 20 will be referred to as angle β(°). When the packaging bag 1 is displayed, the contents 2 are contained inside the packaging bag 1, so the back of the bag body 10 may be bent (for example, bulging). If the back of the bag body 10 is curved at the position of the connecting portion 3, the angle β may be the angle between the tangent m to the back film portion 112 at the position of the connecting portion 3 and the flap 20 (for example, the second side film portion 22).

[0087] The packaging bag 1 may be configured to satisfy at least one of the following conditions C1, C2, C3, C4a, and C4b.

[0088] [Condition C1] The packaging bag 1 is in contact with the mounting surface P, and the first leading edge 10a and the flap leading edge 20a of the packaging bag 1 are in contact with the mounting surface P. The packaging bag 1 is standing upright on the mounting surface P such that the angle α is greater than 45 degrees and less than 90 degrees, and the angle β is 10 degrees or more and 15 degrees or less.

[0089] In other words, the packaging bag 1 may be configured to be self-supporting on the mounting surface P with the flap 20 side facing downwards, satisfying the following equations (1) and (2). 45 degrees<α<90 degrees...(1) 10 degrees≦β≦15 degrees...(2)

[0090] Angles α and β can be angles at any position in the width direction of the packaging bag 1 (the X direction in Figure 2), as long as they are the same angle at the same position in the width direction of the packaging bag 1. For example, angles α and β are angles at the center in the width direction of the packaging bag 1 (the X direction in Figure 2). The same applies to angles θa and θb, which will be described later.

[0091] The above condition C1 can be achieved, for example, by adjusting the amount of contents 2, the size of the packaging bag 1, etc.

[0092] [Condition C2] The loop stiffness values ​​(first loop stiffness values) of seal portion 10Sa and seal portion 20Sa are 400 mN or more, and, The flap 20 includes a predetermined portion in which the loop stiffness value (second loop stiffness value) is 3000 mN or more.

[0093] Under condition C2 above, the loop stiffness value is the value measured under the measurement conditions of a sample width of 10 mm, a loop length of 80 mm, and a compression distance of 10 mm. The loop stiffness value may be the value measured by a loop stiffness measuring instrument. An example of a loop stiffness measuring instrument is the Loop Stiffness Tester (registered trademark) DA type manufactured by Toyo Seiki Co., Ltd. If the loop stiffness value is 2000 mN or more, the loop stiffness value may be the value measured using the compression function of a tensile testing machine under the same measurement conditions as above.

[0094] The above-mentioned specified portion may be a zipper tape 30 or a watertight seal portion 40.

[0095] Under condition C2, the loop stiffness values ​​of the seal portion 10Sa and the seal portion 20Sa may be, for example, 1500 mN or less. The loop stiffness value of the above-mentioned predetermined portion may be 4500 mN or less.

[0096] The loop stiffness value of the film F constituting the packaging bag 1, that is, the loop stiffness values ​​of the surface film portion 111, the back film portion 112, the first side film portion 21, and the second side film portion 22, may be 100 mN or less when measured using the same measurement method (including measurement conditions) as when measuring the loop stiffness described in condition C2. The loop stiffness value of film F may be 25 mN or more.

[0097] [Condition C3] The ratio of length L4 to length L3 (L4 / L3) is 0.9 or greater and 1.0 or less.

[0098] [Condition C4a] The ratio of length L1 to length L2 (L1 / L2) is greater than 0.5 and less than or equal to 1.0.

[0099] [Condition C4b] The ratio of length L1 to length L2 (L1 / L2) is greater than 1 and less than or equal to 1.5.

[0100] [Manufacturing method for packaging bags] Next, an embodiment of the manufacturing method for the packaging bag 1 will be described using Figures 8 to 12.

[0101] The manufacturing method for the packaging bag 1 includes an intermediate manufacturing step, a steam vent forming step, a side edge sealing step, and a folding step.

[0102] [Intermediate manufacturing process] In the intermediate manufacturing process, the intermediate 50 shown in Figures 8 and 9 is manufactured using a single film F. Figure 8 is a diagram illustrating the structure of the intermediate 50. Figure 9 is a plan view of the intermediate 50 shown in Figure 8. Figure 9 shows the intermediate 50 with its third portion 503 tilted toward the second portion 502. In Figure 9, the zipper tape 30 located within the first portion 501 is also shown with a solid line. The hatching shown in Figure 9 is used to indicate the sealed portion of the intermediate 50. In the description of the manufacturing method of the packaging bag 1, the first predetermined direction s and the second predetermined direction t shown in Figures 8 and 9 may be used. The second predetermined direction t is the direction that intersects with the first predetermined direction s. Hereafter, unless otherwise specified, the second predetermined direction t is perpendicular to the first predetermined direction s.

[0103] The intermediate body 50 has a first surface portion 51, a second surface portion 52, and a third surface portion 53. The first surface portion 51 has a first flap region 511 and a first a-bag body region 512 along a first predetermined direction s. The second surface portion 52 and the third surface portion 53 are arranged along the first predetermined direction s. The second surface portion 52 has a second flap region 521 and a second a-bag body region 522. The third surface portion 53 has a first b-bag body region 531 and a second b-bag body region 532. The inner surface of the intermediate body 50 is a heat-sealed surface.

[0104] The first flap region 511 and the second flap region 521 are opposite each other. The first flap region 511 and the second flap region 521 constitute the first part 501 of the intermediate 50.

[0105] The first part 501 corresponds to the flap 20. The first flap region 511 is the region corresponding to the second side film portion 22. The second flap region 521 is the region corresponding to the first side film portion 21.

[0106] The first tip 501a of the first portion 501 is sealed. The first tip 501a is the end of the first portion 501 that is opposite to the second portion 502. The first tip 501a corresponds to the flap tip 20a of the flap 20. The sealing of the first tip 501a forms the seal portion 20Sa.

[0107] The first a bag body region 512 and the first b bag body region 531 are opposite each other. The first a bag body region 512 and the first b bag body region 531 constitute the second part 502 of the intermediate 50.

[0108] The second section 502 corresponds to the second fuselage section 11B. The first bag body area 512 is the area corresponding to the second back film portion 112B. The first b bag body region 531 is the region corresponding to the second surface film portion 111B.

[0109] The second tip 502a of the second portion 502 is open. The second tip 502a is the end of the second portion 502 that is located opposite to the first portion 501. The second tip 502a corresponds to the second tip 10b of the bag body 10.

[0110] The seconda bag body region 522 is a region of the second face portion 52 that is bent in the opposite direction to the first face portion 51. The secondb bag body region 532 is a region of the third face portion 53 that is bent in the opposite direction to the first face portion 51. The seconda bag body region 522 and the secondb bag body region 532 are opposite each other. The seconda bag body region 522 and the secondb bag body region 532 constitute the third part 503 of the intermediate body 50.

[0111] The third section 503 corresponds to the first fuselage section 11A. The second bag body area 522 is the area corresponding to the first back film portion 112A. The second b bag body region 532 is the region corresponding to the first surface film portion 111A.

[0112] The third tip 503a of the third section 503 is sealed. The third tip 503a is the end of the third section 503 that is located opposite to the connection portion 503b (see Figure 9) between the first section 501 and the second section 502 and the third section 503. The third tip 503a corresponds to the first tip 10a of the first body section 11A. The sealing portion 10Sa is formed by sealing the third tip 503a. The connection portion 503b corresponds to the connecting portion 3.

[0113] A zipper tape 30 is attached to the first part 501. Since the first part 501 corresponds to the flap 20, the zipper tape 30 is attached in the same manner as described with reference to Figure 5.

[0114] In this embodiment, a watertight seal portion 40 is formed in the first portion 501. The watertight seal portion 40 is a seal portion for separating the chuck tape 30 from the internal space of the second portion 502 and the third portion 503. Since the first portion 501 corresponds to the flap 20, the watertight seal portion 40 is formed in the first portion 501 as described with reference to Figure 5. Specifically, the watertight seal portion 40 is formed by joining a watertight film 41 connected to the chuck tape 30 to the second flap region 521. In the embodiment shown in Figure 9, the watertight film 41 and the second flap region 521 are sealed by a corrugated seal 42.

[0115] [Steam venting section formation process] In the steam venting section formation process, a steam venting section 311 is formed in the intermediate body 50, as shown in Figure 10. Figure 10 is a plan view of the intermediate body 50 in which the steam venting section 311 has been formed. In this embodiment, a steam venting section 311 is formed as a weakly occlusal section by crushing a part of the occlusal section 31 of the chuck tape 30 by pressurization, heat deformation, etc.

[0116] [Side edge sealing process] In the side edge sealing process, as shown in Figure 10, the pair of side edges 50a and 50b of the intermediate body 50 are sealed with the third portion 503 bent toward the second portion 502 so that the second b bag body region 532 is in contact with the first b bag body region 531. The pair of side edges 50a and 50b are the side edges of the intermediate body 50 in a second predetermined direction t. The method of sealing is not limited, but in this embodiment, the pair of side edges 50a and 50b of the intermediate body 50 are heat-sealed with the third portion 503 bent toward the second portion 502. As a result, the inner surfaces of each of the pair of side edges of the first portion 501, the inner surfaces of each of the pair of side edges of the second portion 502, and the inner surfaces of each of the pair of side edges of the third portion 503 are heat-sealed.

[0117] By performing the side edge sealing process, as shown in Figure 11, the sealing portions 10Sc, 10Sd, 20Sb, and 20Sc of the packaging bag 1 are formed on the intermediate body 50. Figure 11 is a diagram illustrating the side edge sealing process. With the third portion 503 tilted toward the second portion 502, the pair of side edges 50a and 50b of the intermediate body 50 are heat-sealed (sealed), so that the multiple sealing portions formed in the side edge sealing process are formed together.

[0118] During heat sealing, the pair of side edges 50a and 50b of the intermediate body 50 are pressed in the thickness direction, leaving a mark of the third tip 503a of the third portion 503 on the sealing portion 10Sc and sealing portion 10Sd. This forms the linear mark 13 shown in Figure 2.

[0119] [Folding process (reversal process)] In the folding process, as shown in Figure 12, the third portion 503 of the intermediate body 50 that has undergone the side edge sealing process is folded back toward the first portion 501. In other words, the third portion 503 is inverted. Specifically, the third portion 503 is folded back toward the first portion 501 so that the outer surface of the secondb bag body region 532 and the outer surface of the firstb bag body region 531 form a flat surface. This produces the packaging bag 1A shown in Figure 13. Packaging bag 1A corresponds to packaging bag 1 before the contents 2 are placed inside. Figure 12 is a diagram illustrating the folding process. Figure 13 is a plan view of packaging bag 1A produced by the folding process, and corresponds to a plan view of packaging bag 1 before the contents 2 are placed inside.

[0120] Packaging bag 1A differs from packaging bag 1 in that a seal portion 10Sb is not formed on the second leading edge portion 10b and it does not contain contents 2. Aside from the above differences, the configuration of packaging bag 1A is the same as that of packaging bag 1.

[0121] [Contents supply process] In the contents supply process, contents 2 are supplied into the bag body 10 of the packaging bag 1A. The second tip 10b of the packaging bag 1A is open. Therefore, in the contents supply process, the second tip 10b is used as the supply opening 14, and contents 2 are supplied into the bag body 10 from the supply opening 14.

[0122] [Sealing process] After the contents supply process is carried out, the supply opening 14 (second tip 10b) is heat-sealed. This forms a sealed portion 10Sb, and the contents 2 are sealed inside the packaging bag 1. As a result, the packaging bag 1 is obtained.

[0123] If the packaging bag 1 has an opening trigger portion 121 and an opening trigger portion 231, a process for forming the opening trigger portion 121 and the opening trigger portion 231 is carried out. For example, the process for forming the opening trigger portion 121 may be carried out between the side edge sealing process and the folding process, and the process for forming the opening trigger portion 231 may be carried out after the folding process. If the opening trigger portion 121 and the opening trigger portion 231 are formed at an equidistant distance from the connecting portion 503b (connecting portion 3), the opening trigger portions 121 and 231 may be formed simultaneously after the folding process with the first portion 501 and the third portion 503 overlapping.

[0124] If the packaging bag 1 has opening guide lines as opening sections 12 and 23, the opening guide lines may be formed in advance in the film F before the intermediate body 50 is formed, at the locations that will become the opening sections 12 and 23.

[0125] An example of the intermediate manufacturing process included in the manufacturing method of the packaging bag 1 will be specifically described. In the intermediate manufacturing process, the intermediate 50 is manufactured by folding the intermediate-forming region of a single film F. The following describes the case where the entire film F is the intermediate-forming region. However, the intermediate-forming region may be only a part of the film F.

[0126] First, as shown in Figure 14, the film F is folded to form the first part 501, the second part 502, and the third part 503 (folding process). Figure 14 is a diagram illustrating the folding process.

[0127] By folding the film F, the first surface portion 51, the second surface portion 52, and the third surface portion 53 are formed in the regions corresponding to the first surface portion 51, the second surface portion 52, and the third surface portion 53 of the film F. For the sake of explanation, the regions corresponding to the first surface portion 51, the second surface portion 52, and the third surface portion 53 of the film F will also be simply referred to as "first surface portion 51," "second surface portion 52," and "third surface portion 53," and an example of the folding process described above will be explained.

[0128] (i) The film F is folded such that the sealant layer F1 is located on the inside at the boundary between the first surface portion 51 and the second surface portion 52 of the film F, and the second flap region 521 is located on the first flap region 511 of the first surface portion 51. This forms the first portion 501. The boundary between the folded first surface portion 51 and the second surface portion 52 is the first tip portion 501a. Therefore, at the first tip portion 501a, the first flap region 511 and the second flap region 521 are connected, and the first tip portion 501a is closed.

[0129] (ii) The film F is folded such that the sealant layer F1 is located on the inside at the boundary between the first surface 51 and the third surface 53 of the film F, and the first b bag body region 531 is located on the first a bag body region 512 of the first surface 51. This forms the second portion 502. The boundary between the folded first surface 51 and the third surface 53 is the second tip portion 502a. Therefore, at the second tip portion 502a, the first a bag body region 512 and the first b bag body region 531 are connected, and the second tip portion 502a is closed.

[0130] (iii) The second surface 52 is folded at the boundary between the second flap region 521 and the second a bag body region 522, and the third surface 53 is folded at the boundary between the first b bag body region 531 and the second b bag body region 532, so that the inner surface of the second a bag body region 522 in the second surface 52 faces the inner surface of the second b bag body region 532 in the third surface 53. As a result, the first b bag body region 531 and the second b bag body region 532 are arranged opposite each other in a prism-like manner, and the third portion 503 is formed. At this stage, the third tip 503a of the third portion 503 is not closed.

[0131] The order in which film F is folded, as described in (i), (ii), and (iii) above, is not limited.

[0132] In the folding process described above, of the first b bag body region 531 and the second b bag body region 532, which are arranged opposite each other in a gable shape, the portion closer to the second flap region 521 and the first b bag body region 531 may be temporarily fixed (temporarily sealed) from the viewpoint of workability in subsequent processes.

[0133] In this embodiment, the above folding process is carried out by placing a plate 60 on the first surface portion 51 of the film F, as shown in Figure 14, and folding the film F along the plate 60 so that the sealant layer F1 of the film F faces inward.

[0134] Next, as shown in Figure 15, the third tip portion 503a of the third portion 503 is sealed (third tip sealing step). This forms the sealed portion 10Sa. Figure 15 is a diagram illustrating the third tip sealing step.

[0135] After forming the seal portion 10Sa, as shown in Figure 16, the first tip portion 501a is opened (first tip portion opening step) and the second tip portion 502a is opened (second tip portion opening step). In the first tip portion opening step, the first tip portion 501a may be opened by cutting it along a second predetermined direction t. In the second tip portion opening step, the second tip portion 502a may be opened by cutting it along a second predetermined direction t. The order of the first tip portion opening step and the second tip portion opening step is not limited. Figure 16 is a diagram illustrating the first tip portion opening step and the second tip portion opening step.

[0136] After the first tip opening step, as shown in Figure 17, a chuck tape 30 with a watertight film 41 fixed to it is attached to the opened first section 501 (chuck tape attachment step). Figure 17 is a diagram illustrating the chuck tape attachment step.

[0137] In the chuck tape attachment process, the chuck tape 30, to which the watertight film 41 is fixed, is placed within the first section 501. Then, the chuck tape 30 is fixed to the first section 501. The method of fixing the chuck tape 30 to the first section 501 is the same as in the explanation of the method of fixing the chuck tape 30 to the first side film section 21 and the second side film section 22 (explanation using Figure 5), provided that the first side film section 21 and the second side film section 22 are replaced with the first flap region 511 and the second flap region 521.

[0138] After the chuck tape attachment process, a watertight seal portion 40 is formed by joining the watertight film 41 to the inner surface of the first portion 501, as shown in Figure 18 (watertight seal portion formation process). Figure 18 is a diagram illustrating the watertight seal portion formation process.

[0139] The watertight seal portion 40 is formed in the same manner as described in the method for forming the watertight seal portion 40 using Figure 5, but with the first side film portion 21 replaced by the second flap region 521. The sealing of the end region 411 of the watertight film 41 and the second flap region 521 can be carried out by a hot plate seal. For example, the sealing of the end region 411 of the watertight film 41 and the second flap region 521 can be carried out by a hot plate seal formed into a corrugated shape. In this case, a corrugated seal 42 is formed.

[0140] After performing the chuck tape attachment process and the watertight seal formation process, the open first tip portion 501a is sealed (first tip sealing process). The first tip portion 501a is sealed, for example, by heat sealing. This forms the sealed portion 10Sa, and the intermediate body 50 shown in Figures 8 and 9 is obtained.

[0141] In the above example of the intermediate manufacturing method, the intermediate 50 may be manufactured using a strip-shaped film F extending along a second predetermined direction t. In this case, multiple intermediate formation regions may be set on the strip-shaped film F along the second predetermined direction t, and each step of the intermediate manufacturing process may be carried out sequentially in each intermediate formation region while the film F is transported along the second predetermined direction t. In this case, multiple intermediates 50 are manufactured along the second predetermined direction t. Therefore, each step after the intermediate manufacturing process, such as the steam venting section formation step, is carried out while transporting the multiple intermediates 50 along the second predetermined direction t, thereby manufacturing multiple packaging bags 1A corresponding to the multiple intermediates 50. In this case, since the multiple packaging bags 1A are connected along the second predetermined direction t, each packaging bag 1A can be obtained by separating the multiple packaging bags 1A. As a result, a packaging bag 1 corresponding to each packaging bag 1A is manufactured.

[0142] When displaying the packaging bag 1, as shown in Figure 1, it is displayed in the store with the flap 20 side facing downwards and the flap 20 spread out relative to the first body portion 11A. That is, the method of displaying the packaging bag 1 includes the step of placing the packaging bag 1 on the mounting surface P such that the first tip portion 10a and the flap tip portion 20a are in contact with the mounting surface P.

[0143] A consumer who has purchased the packaging bag 1 opens the flap 20 by tearing the portion of the flap 20 closest to the tip 20a in the width direction. The consumer may open the flap 20 by tearing it with their fingers, or by using a sharp object such as scissors or a knife. After opening the flap 20, the consumer opens the zipper tape 30. By opening the zipper tape 30, the end region 411 of the watertight film 41, which was detachably bonded to the first side film portion 21, also peels off from the first side film portion 21. In this state, the consumer puts the additional contents into the bag body 10 through the flap 20. This places the food to be cooked inside the packaging bag 1. The consumer then seals the food to be cooked (contents 2 and additional contents) by closing the zipper tape 30. Next, the consumer places the packaging bag 1 in the microwave oven and heats it.

[0144] In this embodiment, the packaging bag 1 is placed flat (or horizontally) inside the microwave oven so that the surface film portion 111 is in contact with the heating tray (or similar) inside the microwave oven. That is, the surface film portion 111 of the packaging bag 1 corresponds to the bottom surface (or bottom film portion) when the packaging bag 1 is placed inside the microwave oven. When the steam generated inside the packaging bag 1 reaches a predetermined pressure during the heating of the food in the microwave oven, the steam vent portion 311 opens, and steam is released to the outside of the packaging bag 1 from the steam vent portion 311. In a flat-placed packaging bag 1, the flap 20 is located on the opposite side of the packaging bag 1 from the heating tray, allowing steam to escape easily.

[0145] After the microwave cooking is complete, the consumer removes the packaging bag 1 from the microwave. Then, they tear the part of the bag body 10 near the seal portion 10Sa in the width direction and remove the cooked food from the packaging bag 1 to a plate or other surface through the first body portion 11A. This allows the consumer to eat the cooked food.

[0146] Packaging bag 1 is sold with contents 2 (e.g., cooking seasoning liquid) already contained within it. Consumers who purchase packaging bag 1 containing contents 2 can easily prepare their desired dish by adding fresh additional contents (ingredients, ingredients, etc.) immediately before heating. As described above, since fresh additional contents can be added to packaging bag 1 before heating in a microwave oven, the flavor and nutritional value of the additional contents such as ingredients are less likely to be lost.

[0147] In packaging bag 1, a zipper tape 30 is provided on a flap 20 connected to the bag body 10, but the bag body 10 that contains the contents 2 does not have a zipper tape 30. Therefore, even if the contents 2 are liquid, for example, it is unlikely that the contents 2 will leak out of packaging bag 1.

[0148] The first body portion 11A of the packaging bag 1 is part of the bag body 10, and the flap 20 is a portion that protrudes outward from the bag body 10. When the contents 2 are heated in a microwave oven, the contents 2 are placed in the bag body 10. The heated contents 2 are removed through the first body portion 11A. Since the first body portion 11A and the second body portion 11B of the bag body 10 are arranged along the Y direction, for example, it is easier to remove the contents 2 from the first body portion 11A than from the flap 20.

[0149] In packaging bag 1, the zipper tape 30 is attached to the flap 20, not to the bag body 10 that contains the contents 2. In packaging bag 1, if the watertight seal portion 40 is provided on the flap 20, even if packaging bag 1 is dropped during distribution, the impact on the watertight seal portion 40 can be reduced. This point will be explained in detail.

[0150] If the packaging bag 1 containing the contents 2 were to fall, the second body section 11B containing the contents 2 would fall first. Therefore, the impact of the fall would be transmitted from the second body section 11B to the first body section 11A. If a flap 20 is positioned on the first body section 11A, the impact of the fall would be distributed between the first body section 11A and the flap 20. For example, in a packaging bag without a flap 20 where a zipper tape is attached to the part corresponding to the first body section and a watertight seal section is formed, the load on the watertight seal section formed on the flap 20 would be smaller than the load on the watertight seal section due to the transmitted impact of the fall. Therefore, the watertight seal section 40 is less likely to be damaged.

[0151] Since the packaging bag 1 has a steam vent 311, steam generated when the packaging bag 1 containing the food to be cooked (contents 2 and additional contents) is heated in a microwave oven can be automatically discharged to the outside. Therefore, it is possible to prevent the packaging bag 1 from bursting during microwave heating. As described above, since the packaging bag 1 has a function that allows steam generated during heating to be automatically discharged, safety is also ensured, such as preventing burns to the hands when handling the packaging bag 1 after heating.

[0152] One of the advantages of cooking using a microwave oven is that it does not require the use of fire. By using packaging bag 1, cooking can be done in a microwave oven, thus eliminating the need for fire. After adding additional ingredients to packaging bag 1, the food can be cooked by heating it in a microwave oven. Therefore, using packaging bag 1 makes cooking easy and reduces the time and effort required for cleaning up pots, cooking utensils, and dishes afterward.

[0153] When displaying packaging bags 1 on shelves in a retail store, it is easier to display more packaging bags 1 in a way that is easily visible to consumers if they are placed upright rather than lying flat.

[0154] The packaging bag 1 has a flap 20. In the packaging bag 1, the length L3 of the first body portion 11A is greater than or equal to the length of the flap 20. Therefore, the packaging bag 1 can stand on its own by placing the flap 20 downwards and supporting it with the bag body 10 using the flap 20. In this case, the packaging bag 1 does not need to be equipped with any auxiliary devices to make it stand on its own, so the manufacturing cost of the packaging bag 1 can be reduced. The retailer does not need to prepare a support separate from the packaging bag 1 to make it stand on its own, so the burden on the retailer can also be reduced.

[0155] A zipper tape 30 is provided on the flap 20. This improves the overall rigidity of the flap 20. As a result, when the packaging bag 1 is made to stand upright, the flap 20 makes it easier to support the bag body 10. Furthermore, the zipper tape 30 makes it easier to maintain the close proximity of the first side film portion 21 and the second side film portion 22. In this case, the flap 20 effectively functions as a single film having the thickness of two films F. From this viewpoint as well, the rigidity of the flap 20 is improved, making it easier to effectively utilize the flap 20 as a support for the bag body 10. In the configuration in which a watertight seal portion 40 is provided on the flap 20, the rigidity of the flap 20 is further improved, and the close proximity of the first side film portion 21 and the second side film portion 22 is more easily maintained.

[0156] When the packaging bag 1 is placed in a self-supporting position at a retail store, for example, a support or other object may be prepared separately from the packaging bag 1, and the second tip portion 10b may be placed facing downwards. However, in this case, the flap 20 is located on the upper side along with the first body portion 11A, making the packaging bag 1 prone to bending. The flap 20 has a zipper tape 30 in addition to the first side film portion 21 and the second side film portion 22, so if the flap 20 is positioned on the upper side, the packaging bag 1 is prone to bending. If the flap 20 has a watertight seal portion 40, the packaging bag 1 is even more prone to bending. When the packaging bag 1 is bent, it is difficult for consumers to recognize the product, and if the packaging bag 1 (product) is sold in a bent state, the consumer's image of the product is likely to deteriorate.

[0157] The packaging bag 1 is configured so that the first body portion 11A and the flap 20 are positioned downwards when sold, thus preventing the packaging bag 1 from bending during sale. Because bending of the packaging bag 1 during sale is prevented in this way, defects such as pinholes caused by bending can also be prevented.

[0158] The packaging bag 1 has a guidance information display section 4. The guidance information display section 4 is provided on the surface film portion 111 and is configured so that the information can be read correctly when the first tip portion 10a is positioned downwards. Therefore, when selling the packaging bag 1, the salesperson can set up the packaging bag 1 so that the first tip portion 10a is definitely facing downwards (in other words, the first body portion 11A and the flap 20 are facing downwards).

[0159] When packaging bag 1 satisfies at least one of conditions C1 to C3, packaging bag 1 is easily able to stand upright stably.

[0160] For example, if packaging bag 1 satisfies condition C1, then packaging bag 1 can stand on its own, as shown in Figure 7, in order to satisfy the following condition C5.

[0161] [Condition C5] When the packaging bag 1 is placed upright so that its first tip 10a and flap tip 20a are in contact with the mounting surface P, and position Ga is defined as the position in the U-axis direction of the center of gravity G of the entire packaging bag 1 including the contents 2, position Ga is located between the first tip 10a and the flap tip 20a.

[0162] In this case, the center of gravity G of the entire packaging bag 1 is located between the first tip 10a and the flap tip 20a in the U-axis direction. Therefore, for example, if the center of gravity G were located opposite the first tip 10a to the flap tip 20a, the packaging bag 1 is less likely to tip over and is easier to make stand upright stably.

[0163] When angle α satisfies equation (1), the position Ub shown in Figure 7 is located between the first tip 10a and the flap tip 20a, making it easier for the packaging bag 1 to stand upright stably. Position Ub is the position of the connecting part 3 on the U-axis.

[0164] If condition C1 is met, the angle θb shown in Figure 7 can also satisfy the condition that it is greater than or equal to angle θa and less than or equal to 90 degrees. Angle θa is the angle between the imaginary line n connecting the center of gravity G of the packaging bag 1 containing the contents 2 and the origin O, and the U axis, as shown in Figure 7. Angle θb is the angle between the flap 20 and the U axis, as shown in Figure 7. Angle θb may be the angle between the flap 20 and the U axis when the flap 20 is considered as a single film.

[0165] When the packaging bag 1 satisfies condition C2, the sealing portion 10Sa and sealing portion 20Sa tend to have a certain degree of rigidity, so when the packaging bag 1 is made to stand upright, the sealing portion 10Sa and sealing portion 20Sa are less likely to bend. Therefore, the packaging bag 1 is more likely to stand upright stably. When the packaging bag 1 satisfies condition C2, the rigidity of the flap 20 is improved, so the bag body 10 can be supported by the flap 20. Therefore, the stability of the packaging bag 1 when it is made to stand upright is improved.

[0166] If length L4 is longer than length L3, the packaging bag 1 is more likely to tip forward. If length L4 is too short compared to length L3, the angle θa tends to be smaller, causing the packaging bag 1 to tip backward or droop at the top. Therefore, when the packaging bag 1 satisfies condition C3, it is less likely to tip forward or backward, and drooping at the top is also suppressed. As a result, the stability of the packaging bag 1 is improved.

[0167] The loop stiffness value of film F may be 100 mN or less. In this case, the handling of packaging bag 1 is improved when putting contents 2 and additional contents into packaging bag 1, or when removing cooked food. When the loop stiffness value of film F is 100 mN or less, packaging bag 1 is easy to manufacture using film F. When the loop stiffness value of film F is 25 mN or more, deformation such as bending or sagging of the top of packaging bag 1 can be suppressed when packaging bag 1 is made to stand upright.

[0168] When packaging bag 1 satisfies condition C4a, it exhibits a horizontally elongated rectangular shape when viewed from the front. Therefore, even when the shelf height spacing in a retail store is narrow, it can provide surface information equivalent to the horizontal area.

[0169] When packaging bag 1 satisfies condition C4b, it takes the shape of a vertically elongated rectangle when viewed from the front. Therefore, more packaging bags 1 can be placed in the width direction of the sales area set up in the retail store. Thus, a limited sales area can be effectively utilized while ensuring a certain volume of contents.

[0170] When packaging bag 1 is installed in a retail store, it is preferable that it be displayed in a manner that satisfies condition C1. This further ensures the self-supporting ability of packaging bag 1.

[0171] The packaging bag 1 according to this embodiment is a flat-type packaging bag that is placed flat so that the surface film portion 111 is in contact with the tray of the microwave oven when heated in a microwave oven. As a form of packaging bag, there is also a known standing-type packaging bag that is intended to be placed upright when heated in a microwave oven. Standing-type packaging bags are basically manufactured with the assumption that the packaging bag will be placed upright when heated in a microwave oven. Generally, microwave ovens are shorter in height than in width, so the height of the packaging bag is more limited in the case of standing-type packaging bags. In contrast, in the flat-type, the packaging bag 1 containing the contents 2 is placed horizontally inside the microwave oven, so the height restriction is more relaxed than with standing-type packaging bags. Therefore, with the flat-type packaging bag 1, it is easier to secure capacity than with standing-type packaging bags, and for example, it is possible to achieve a large capacity.

[0172] With the flat-lay type packaging bag 1, the height restrictions are also relaxed, making it easier to change the size (capacity) to meet consumer needs. Since the packaging bag 1 is placed flat inside the microwave oven, it will not tip over during cooking. Therefore, the packaging bag 1 does not require any components to prevent tipping. Because the contents 2 are cooked with the packaging bag 1 placed flat inside the microwave oven, uneven cooking of the contents 2 is less likely to occur.

[0173] Next, we will describe the experimental examples. In describing the experimental examples, for the sake of clarity, elements similar to those described in the previous embodiments will be denoted by the same reference numerals, and redundant explanations will be omitted. For the sake of clarity, the same applies to the comparative experimental examples that do not satisfy the conditions of equation (2).

[0174] [Experimental Example 1] In Experimental Example 1, the packaging bag 1 shown in Figures 1 to 4 was manufactured using a film F having the following layer structure. In the following layer structure, " / / " indicates that adjacent films are joined together with an adhesive. (Layer structure of film F) Transparent barrier vapor-deposited PET film / / PET film / / CPP film

[0175] The transparent barrier vapor-deposited PET film was a film in which a vapor-deposited layer was formed on a 12 μm thick polyethylene terephthalate (PET) film. The material of the vapor-deposited layer was an oxide mainly composed of silica. The PET film was a biaxially oriented PET film with straight-line cutting properties. The thickness of the PET film was 12 μm. The thickness of the CPP film was 60 μm. The CPP film was the layer corresponding to the sealant layer F1 in film F.

[0176] The lengths L1, L2, L3, and L4 in packaging bag 1 of Experimental Example 1 were as follows, as shown in Figure 19. Figure 19 also shows the ratios (L1 / L2) and (L4 / L3). L1 = 210 mm L2 = 170mm L3 = 45mm L4 = 50mm

[0177] In Experimental Example 1, the seal width of the seal portion 10Sa and seal portion 20Sa in packaging bag 1 was 10 mm.

[0178] For the chuck tape 30, MFP-339Z3 manufactured by Idemitsu Unitech Co., Ltd. was used. In Experimental Example 1, a steam vent portion 311 was formed in the central part of the occlusal portion 31 of the chuck tape 30 in the X direction. The watertight seal portion 40 was formed by peelably bonding a watertight film 41 to the inner surface of the first side film portion 21. The watertight seal portion 40 was bonded to the inner surface of the first side film portion 21 by a corrugated seal 42.

[0179] In Experimental Example 1, 100g of water was placed in packaging bag 1 as contents 2.

[0180] <Loop stiffness> The loop stiffness value of film F prepared in Experimental Example 1 was measured. The loop stiffness measuring instrument used for the measurement was a Loop Stiffness Tester DA type manufactured by Toyo Seiki Co., Ltd. The measurement conditions were as follows. The loop stiffness value was measured for three sample pieces, and the average value of these measurements was adopted as the loop stiffness value of film F. The measured loop stiffness value of film F was 50 mN. (Measurement conditions) Sample width: 10mm Loop length: 80mm Compression distance: 10mm

[0181] The loop stiffness of seal portion 10Sa and seal portion 20Sa was measured using the same loop stiffness measuring instrument and under the same measurement conditions as for film F. Similar to the case of film F, the loop stiffness values ​​were measured for three sample pieces, and the average value of these values ​​was adopted as the loop stiffness value of the target (seal portion 10Sa or seal portion 20Sa). The loop stiffness values ​​of seal portion 10Sa and seal portion 20Sa were 800 mN.

[0182] A sample piece with a width of 10 mm, including the zipper tape 30, was cut from the flap 20 of the packaging bag 1 in Experimental Example 1, and the loop stiffness value was measured using the compression function of a tensile testing machine under the same measurement conditions as for film F. As with film F, the loop stiffness value was measured for three sample pieces, and the average value was adopted as the loop stiffness value of the sample piece including the zipper tape 30. The tensile testing machine was an AG-IS manufactured by Shimadzu Corporation. The loop stiffness value of the sample piece including the zipper tape 30 was 5800 mN.

[0183] A sample piece with a width of 10 mm, including the watertight seal portion 40, was cut from the flap 20 of the packaging bag 1 in Experimental Example 1, and the loop stiffness value was measured using the compression function of a tensile testing machine under the same measurement conditions as for film F. As with film F, the loop stiffness value was measured for three sample pieces, and the average value was adopted as the loop stiffness value of the sample piece including the watertight seal portion 40. The tensile testing machine was an AG-IS manufactured by Shimadzu Corporation. The loop stiffness value of the sample piece including the watertight seal portion 40 was 940 mN.

[0184] <Assessment of independence> The packaging bag 1 of Experimental Example 1 was made to stand upright with the flap 20 facing downwards. The packaging bag 1 of Experimental Example 1 was able to stand upright stably. The angles α and β of the packaging bag 1 in the self-standing state were obtained. The angles α and β were obtained by photographing the self-standing packaging bag 1 from the side and analyzing the obtained image. Specifically, in the obtained image, the origin O, U axis, and V axis shown in Figure 7 were set at the center of the packaging bag 1 in the width direction, and the angles α and β at the center were obtained. Furthermore, the position Ga of the center of gravity G on the U axis, the position Ua of the flap tip 20a on the U axis, the position Ub of the connecting part 3 on the U axis, and angles θa and θb were also obtained. The experimental results of Experimental Example 1 are shown in Figure 20.

[0185] [Experimental Example 2] In Experimental Example 2, the same packaging bag 1 as in Experimental Example 1 was manufactured, except that 150g of water was filled into the packaging bag 1 as the contents 2. Therefore, the dimensions (lengths L1 to L4) of the packaging bag 1 in Experimental Example 2 were as shown in Figure 19.

[0186] Since the packaging bag 1 in Experimental Example 2 is the same as the packaging bag 1 in Experimental Example 1, except for the difference in the amount of contents 2, the loop stiffness values ​​of the film F used in the packaging bag 1, the seal portion 10Sa, the seal portion 20Sa, and the zipper tape 30 and watertight seal portion 40 on the flap 20 were the same as in Experimental Example 1.

[0187] The self-standing ability of packaging bag 1 in Experimental Example 2 was evaluated in the same way as in Experimental Example 1. Packaging bag 1 in Experimental Example 2 was also able to stand on its own with the flap 20 facing downwards. The angle α of packaging bag 1 in the self-standing state was 64 degrees, and the angle β was 11 degrees. In Experimental Example 2, the positions Ga, Ua, Ub, angles θa and θb were also obtained. The experimental results for Experimental Example 2 are shown in Figure 20.

[0188] [Experimental Example 3] In Experimental Example 3, the same packaging bag 1 as in Experimental Example 1 was manufactured, except that the length L2 was changed to 150 mm. Therefore, the dimensions (lengths L1 to L4) of packaging bag 1 in Experimental Example 3 were as shown in Figure 19.

[0189] Since the packaging bag 1 in Experimental Example 3 is the same as the packaging bag 1 in Experimental Example 1, except for the difference in length L2, the loop stiffness values ​​of the film F used in the packaging bag 1, the seal portion 10Sa, the seal portion 20Sa, and the zipper tape 30 and watertight seal portion 40 on the flap 20 were the same as in Experimental Example 1.

[0190] Self-standing ability was evaluated for packaging bag 1 in Experimental Example 3 in the same way as in Experimental Example 1. Packaging bag 1 in Experimental Example 3 was also able to stand on its own with the flap 20 facing downwards. The angle α of packaging bag 1 in the self-standing state was 71 degrees, and the angle β was 10 degrees. In Experimental Example 3, the positions Ga, Ua, Ub, angles θa and θb were also obtained. The experimental results for Experimental Example 3 are shown in Figure 20.

[0191] [Experimental Example 4] In Experimental Example 4, the same packaging bag 1 as in Experimental Example 1 was manufactured, except that the length L3 was changed to 45 mm. Therefore, the dimensions (lengths L1 to L4) of packaging bag 1 in Experimental Example 4 were as shown in Figure 19.

[0192] Since the packaging bag 1 in Experimental Example 4 is the same as the packaging bag 1 in Experimental Example 1, except for the difference in length L3, the loop stiffness values ​​of the film F used in the packaging bag 1, the seal portion 10Sa, the seal portion 20Sa, and the zipper tape 30 and watertight seal portion 40 on the flap 20 were the same as in Experimental Example 1.

[0193] Self-standing ability was evaluated for packaging bag 1 in Experimental Example 4 in the same way as in Experimental Example 1. Packaging bag 1 in Experimental Example 4 was also able to stand on its own with the flap 20 facing downwards. The angle α of packaging bag 1 in the self-standing state was 80 degrees, and the angle β was 10 degrees. In Experimental Example 4, the positions Ga, Ua, Ub, angles θa and θb were also obtained. The experimental results for Experimental Example 4 are shown in Figure 20.

[0194] As mentioned above, the packaging bags 1 in Experimental Examples 1-4 were able to stand upright with the flap 20 facing downwards. Although the film F constituting the packaging bags 1 in Experimental Examples 1-4 does not have a printed layer F3, the printed layer F3 is composed of ink and is also thin, so it has virtually no effect on the ability to stand upright.

[0195] As shown in Figure 20, the experimental results indicate that condition C1 was satisfied in the self-standing state of packaging bag 1 in Experimental Examples 1-4. In packaging bag 1 where condition C1 was satisfied, condition C5 was also satisfied. Based on the measurement results of the loop stiffness values ​​described in Experimental Examples 1-4, condition C2 was also satisfied in packaging bag 1 in Experimental Examples 1-4.

[0196] Although embodiments and variations of the present invention have been described above, the present invention is not limited to the embodiments and variations described above. The present invention is intended to include all modifications within the scope set forth in the claims and within the meaning and scope equivalent to the claims.

[0197] For example, the packaging bag 1 may have a gusset on the second leading edge 10b side. The packaging bag may be manufactured by a method other than the manufacturing method illustrated. The packaging bag may be manufactured using, for example, two films F. If the packaging bag is manufactured by a method that does not involve the folding process described with reference to Figure 12, the packaging bag will not have the line marks 13.

[0198] The watertight seal portion 40 is not limited to the configuration illustrated in Figure 5. For example, the watertight seal portion may be formed by joining the ends of the base 321 and base 331 shown in Figure 5, near the connecting portion 3. Alternatively, the watertight seal portion may be formed by joining the first side film portion 21 and the second side film portion 22 between the chuck tape 30 and the connecting portion 3.

[0199] The above-mentioned packaging bags are not limited to those that are laid flat during microwave heating.

[0200] The various embodiments described above may be combined as appropriate without departing from the spirit of the present invention. [Explanation of Symbols]

[0201] 1...Packaging bag, 2...Contents, 3...Connecting part, 4...Indicator information display part, 10a...First tip, 10b...Second tip, 10Sa...Seal part (first seal part), 20...Flap, 20a...Flap tip, 20Sa...Seal part (second seal part), 21...First side film part, 21...First side film part, 22...Second side film part, 30...Chuck tape, 40...Watertight seal part, 111...Surface film part, 112...Back film part, 112A...First back film part, 112B...Second back film part, 311...Steam vent part, P...Placement surface.

Claims

1. A packaging bag containing contents to be heated in a microwave oven, It has opposing surface film portions and back film portions, and the bag body contains the contents, It has opposing first side film portions and second side film portions, and a flap connected to the rear film portion, Equipped with, The bag body has a first tip and a second tip that are located opposite each other with respect to the connection portion with the flap. A first sealing portion is formed at the first tip portion. The aforementioned back film portion has a first back film portion which is the portion between the connecting portion and the first tip portion, and a second back film portion which is the portion between the connecting portion and the second tip portion. The first side film portion is connected to the first rear film portion, The second side film portion is connected to the second rear film portion, A second sealing portion is formed at the tip of the flap, which is located opposite to the connecting portion of the flap. The flap is provided with a zipper tape between the second sealing portion and the connecting portion. A portion of the aforementioned chuck tape has a steam vent formed therein, The length from the connecting portion to the tip of the flap is less than or equal to the length from the connecting portion to the first tip. The surface film portion is provided with a guidance information display section that, when viewed from the surface film portion side, displays information that guides the packaging bag to be positioned with the first leading edge facing downwards when displayed. packaging bag.

2. When the first tip and the tip of the flap are in contact with the mounting surface, and the packaging bag is placed on the mounting surface such that the angle between the flap and the mounting surface is greater than 45 degrees and less than 90 degrees, the angle between the flap and the bag body is 10 degrees or more and 15 degrees or less. The packaging bag according to claim 1.

3. The first loop stiffness values ​​of the first seal portion and the second seal portion are 400 mN or more. The second loop stiffness value of a predetermined portion of the flap other than the first seal portion and the second seal portion is 3000 mN or more. The first loop stiffness value and the second loop stiffness value are values ​​measured under the measurement conditions of a sample width of 10 mm, a loop length of 80 mm, and a compression distance of 10 mm. The packaging bag according to claim 1 or 2.

4. The flap is provided with a watertight sealing portion between the zipper tape and the connecting portion for separating the zipper tape from the bag body. The predetermined portion is the chuck tape or the watertight seal portion. The packaging bag according to claim 3.

5. The ratio of the length from the connecting portion to the first tip to the length from the connecting portion to the flap tip is 0.9 or more and 1.0 or less. The packaging bag according to claim 1 or 2.

6. In the bag body, the ratio of the length of the bag body in the direction perpendicular to the connecting portion to the length of the bag body in the direction along the connecting portion is 0.5 or more and 1.0 or less. The packaging bag according to claim 1 or 2.

7. A display method for arranging packaging bags containing contents to be heated in a microwave oven on a display surface, The aforementioned packaging bag is It has opposing surface film portions and back film portions, and the bag body contains the contents, It has opposing first side film portions and second side film portions, and a flap connected to the rear film portion, Equipped with, The bag body has a first tip and a second tip that are located opposite each other with respect to the connection portion with the flap. A first sealing portion is formed at the first tip portion. The aforementioned back film portion has a first back film portion which is the portion between the connecting portion and the first tip portion, and a second back film portion which is the portion between the connecting portion and the second tip portion. The first side film portion is connected to the first rear film portion, The second side film portion is connected to the second rear film portion, A second sealing portion is formed at the tip of the flap, which is located opposite to the connecting portion of the flap. The flap is provided with a zipper tape between the second sealing portion and the connecting portion. A portion of the aforementioned chuck tape has a steam vent formed therein, The length from the connecting portion to the tip of the flap is less than or equal to the length from the connecting portion to the first tip. The surface film portion is provided with a guidance information display section that, when viewed from the surface film portion side, displays information that guides the packaging bag to be positioned with the first leading edge facing downwards when displayed. The packaging bag is placed on the aforementioned surface so that the first tip and the tip of the flap are in contact with the aforementioned surface. Display method.

8. The packaging bag is placed on the aforementioned surface such that the angle between the flap and the aforementioned surface is greater than 45 degrees and less than 90 degrees, and the angle between the flap and the bag body is 10 degrees or more and 15 degrees or less. The display method according to claim 7.

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