JP7567205B2 - Pouch - Google Patents

Description

The present invention relates to a pouch for adding contents before cooking.

Conventionally, there is known a packaging bag that allows food to be cooked in a microwave oven while still in the container, has the effect of steaming the food with the steam generated during cooking, and allows the steam to escape by partially peeling off the heat-sealed part due to the internal steam pressure (see Patent Document 1).

JP 2015-120550 A

On the other hand, pouches equipped with an opening/closing mechanism called a zipper that allows the pouch to be resealed once opened are also known. The opening/closing mechanism called a zipper is a fitting device that can close the opening by fitting a male member and a female member. By using such an opening/closing mechanism, it has become possible to add ingredients or seasonings after opening, reseal the pouch, and cook the food. When pouches containing contents are sold as products, the contents are often filled from the upper side of the pouch. In such cases, if the opening/closing mechanism is formed above the pouch, there is a problem in that the contents tend to adhere to the opening/closing mechanism during filling.

Therefore, the objective of the present invention is to provide a pouch that can be easily opened and closed at a position different from the filling opening for the contents.

In order to solve the above problems, the present invention provides
A pouch having a storage portion between a front film and a back film,
A first edge portion;
a second edge portion opposite the first edge portion;
a third edge and a fourth edge extending between the first edge and the second edge;
an opening/closing mechanism formed between the first edge portion and the second edge portion and closer to the first edge portion,
A third edge seal portion and a fourth edge seal portion are formed on the third edge portion and the fourth edge portion along a direction in which the third edge portion and the fourth edge portion extend,
a slit is formed in a direction connecting the third edge seal portion and the fourth edge seal portion, with one of the front surface film and the back surface film serving as a slit forming surface;
The opening and closing mechanism includes a first member and a second member that fit together,
The pouch is provided, in which the first member and the second member are joined at positions on the slit-forming surface across the slit.

The pouch of the present invention further comprises:
The first member and the second member may be formed by folding back a single continuous member at an end portion of a thin-walled portion of the continuous member.

The pouch of the present invention further comprises:
The inner fitting strength of the fitting may be 3N or more and 40N or less.

In addition, in the present invention,
A method for using a pouch having a storage section between a front film and a back film, and an opening/closing mechanism for opening and closing the storage section between a slit formed in one of the front film and the back film and the storage section, the method comprising the steps of:
a step of opening the opening/closing mechanism to open the pouch and then accommodating a second content through the slit;
and heating the pouch in a microwave oven after closing the opening and closing mechanism.

According to the present invention, it is possible to provide a pouch that can be easily opened and closed at a position different from the filling opening for the contents.

FIG. 1 is a front view showing a pouch according to an embodiment of the present invention. FIG. 2 is a rear view of a pouch according to an embodiment of the present invention. FIG. 2 is an exploded view showing components constituting a pouch according to one embodiment of the present invention. FIG. 2 is a cross-sectional view of a pouch according to one embodiment of the present invention. FIG. 2 is a front view of the pouch after it has been filled and sealed. 4 is a cross-sectional view of components constituting a fitting 20 which is an opening and closing mechanism. FIG. 13 is a diagram showing a state of a tensile test of the opening and closing mechanism. 1 is a cross-sectional view of the pouch when opened by the opening and closing mechanism. FIG.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.
<Basic configuration>
Fig. 1 is a front view showing a pouch according to an embodiment of the present invention. Fig. 2 is a rear view of the pouch according to an embodiment of the present invention. Fig. 3 is an exploded view showing members constituting the pouch according to an embodiment of the present invention. Fig. 4 is a partial cross-sectional view of an opening/closing mechanism of the pouch according to an embodiment of the present invention. The pouch according to the present embodiment shown in Figs. 1 and 2 shows the pouch in a state before being filled with contents (a state in which no contents are filled). The pouch according to the present embodiment has a rectangular shape when viewed from the front, and includes a first edge 4 and a second edge 5 facing each other, and a third edge 6 and a fourth edge 7 extending between the first edge 4 and the second edge 5.

In this specification, the term "rectangle" refers not only to a rectangle with right-angled corners, but also to a rectangle with its four corners beveled to form an outwardly convex arc, and other shapes that can be considered to be approximately rectangular. In this specification, the term "pouch" refers not only to a pouch that is not filled with contents, but also to a pouch that is filled with contents. The pouch of this embodiment has a bottom gusset portion 9 on the second edge 5 side, which has a first pleat portion 9a and a second pleat portion 9b. Because the pouch has the bottom gusset portion 9, the pouch can be made to stand on its own by placing it with the first edge 4 side facing up and the second edge 5 side facing down.

As shown in FIG. 3, the pouch of this embodiment is composed of three laminated films: a substantially rectangular front film 1, a back film 2 having the same shape as the front film 1, and a substantially rectangular bottom film 3. The pouch of this embodiment is formed by joining the three films, the front film 1, the back film 2, and the bottom film 3, at predetermined locations by heat sealing (thermal fusion) or the like. Furthermore, although not shown in FIG. 3, a fitting 20, which serves as an opening and closing mechanism, is joined to the inner surface of the front film 1 by heat sealing or the like.

As shown in FIG. 3, the bottom film 3 is folded in half at the fold 3a, and divided into a first part 3f and a second part 3g with the fold 3a as the boundary. The bottom film 3 has four semicircular cutouts 3b, 3c, 3d, and 3e that cut out the side edges, and the cutouts 3b and 3c, and the cutouts 3d and 3e are provided at positions corresponding to each other when the bottom film 3 is folded in half. The second bottom seal portion 15b, which will be described later, is formed through the cutouts 3b to 3e. In addition, from the viewpoint of stabilizing the self-supporting property when heating in a microwave oven, the distance H1 from the fold 3a to the second edge portion 5 of the pouch in the direction perpendicular to the fold 3a can be appropriately set. The fold 3a is also the boundary between the first fold portion 9a and the second fold portion 9b.

<Each seal part>
As shown in Figures 1 and 2, the pouch of this embodiment includes a bottom seal portion 15, a third edge seal portion 16, and a fourth edge seal portion 17, and the first edge portion 4 side is left unsealed and has an opening for filling the contents. The bottom seal portion 15 includes a first bottom seal portion 15a and a second bottom seal portion 15b. In Figures 1 and 2, each seal portion is indicated by hatching with oblique lines.

The third edge seal portion 16 and the fourth edge seal portion 17 are formed by sealing and joining the front surface film 1 and the back surface film 2. The third edge seal portion 16 is formed along the third edge portion 6 so as to include the third edge portion 6 (the left end in FIG. 1, the right end in FIG. 2), and the fourth edge seal portion 17 is formed along the fourth edge portion 7 so as to include the fourth edge portion 7 (the right end in FIG. 1, the left end in FIG. 2). The seal width of the third edge seal portion 16 and the fourth edge seal portion 17 is preferably, for example, 5 mm or more and 30 mm or less. When the pouch according to this embodiment is heated in a microwave oven or the like, it becomes very hot immediately after heating. Therefore, from the viewpoint of preventing burns when the third edge seal portion 16 and the fourth edge seal portion 17 are held by hand, the seal width can be 15 mm or more. In this embodiment, the seal portion is not particularly designed to prevent burns, so the seal width is about 6 mm. The seal width is the width in a direction perpendicular to the direction in which the seal extends.

The bottom seal portion 15 is a seal portion formed on the second edge portion 5 side (lower side in Figs. 1 and 2) from the folded portion 3a, and is composed of a first bottom seal portion 15a and a second bottom seal portion 15b. The first bottom seal portion 15a is formed by sealing the front film 1 and the first portion 3f of the bottom film 3, and the back film 2 and the second portion 3g of the bottom film 3. The second bottom seal portion 15b is formed by sealing the front film 1 and the back film 2. As shown in Fig. 1, the second bottom seal portion 15b formed on the third edge portion 6 and the fourth edge portion 7 has a semicircular shape with an arc-shaped inner side.

<Bottom gusset>
The first portion 3f of the bottom film 3 and the portion of the front film 1 corresponding to the first portion 3f of the bottom film 3 are joined by the first bottom seal portion 15a to form the first fold portion 9a. The second portion 3g of the bottom film 3 and the portion of the back film 2 corresponding to the second portion 3g of the bottom film 3 are joined by the first bottom seal portion 15a to form the second fold portion 9b. The first fold portion 9a and the second fold portion 9b form the bottom gusset portion 9. In the front view of FIG. 1, the first fold portion 9a is visible below the fold portion 3a. In the rear view of FIG. 2, the second fold portion 9b is visible below the fold portion 3a.

<Storage section>
After the contents are contained through the opening on the first edge 4 side, the first edge seal portion 14 is formed at the first edge seal portion (above the dashed line) indicated as 14a in Figs. 1 and 2, and the pouch is sealed (see Fig. 5). The first edge seal portion 14 is formed along the first edge 4 from the third edge seal portion 16 to the fourth edge seal portion 17. The containing portion 11 is defined by the inner edge of the third edge seal portion 16, the inner edge of the fourth edge seal portion 17, the inner edge of the first bottom seal portion 15a, and the inner edge of the first edge seal portion 14. Therefore, the inner edge of the third edge seal portion 16, the inner edge of the fourth edge seal portion 17, the inner edge of the first bottom seal portion 15a, and the inner edge of the first edge seal portion 14 become the outer edge of the containing portion 11. Fig. 5 is a front view of the pouch after the contents are filled and sealed. For convenience of illustration, the contents are omitted.

<Contents>
The contents are not particularly limited, but are preferably food. The food may be foodstuffs that are the main object of eating, or seasonings that season the foodstuffs. The foodstuffs that are the main object of eating may be, for example, solids, dried foods (dried noodles, dried foodstuffs, powdered seasonings, dried fruits), frozen foods, etc. In this embodiment, these contents that are contained before sealing by the first edge seal portion 14 are the first contents. Then, the user contains the second contents in the pouch. The second contents are contents that the user (consumer) prepares separately. For example, when the first contents are foodstuffs, the second contents can be seasonings, and when the first contents are seasonings, the second contents can be foodstuffs. A seasoning liquid can be used as the first contents, and after filling the pouch, it can be frozen and sold as a frozen meal kit. In this case, the user can put ingredients in through the opening and closing mechanism described later and cook them in a microwave oven or the like.

<Opening and closing mechanism>
Next, the opening and closing mechanism will be described. As shown in FIG. 1, in the pouch of this embodiment, a fitting 20 is formed along the first edge 4 as an opening and closing mechanism capable of opening and resealing the pouch. FIG. 4 is a cross-sectional view of the fitting 20 as the opening and closing mechanism. FIG. 4(a) is a cross-sectional view corresponding to the line A-A shown in FIG. 1, and FIGS. 4(b) and 4(c) are partial enlarged views of the fitting 20 shown in FIG. 4(a). As shown in FIGS. 1 and 4, the pouch is provided with a freely openable fitting 20 consisting of a first member and a second member that fit together, as an opening and closing mechanism, near the first edge 4 of the containing section 11. In this embodiment, the male member 21 will be described as the first member and the female member 22 as the second member, but the female member 22 may be the first member and the male member 21 may be the second member.

As shown in FIG. 1, the belt-shaped fitting 20 is provided along the first edge 4 in a front view. In this embodiment, the longitudinal direction of the fitting 20 is provided parallel to the first edge 4. As shown in FIG. 4(a), the male member 21 has a belt-shaped first base 21a in a front view and a male fitting portion 21b on one side of the first base 21a. The first base 21a has a first portion 21aa near the first edge 4 and a second portion 21ab near the second edge 5, and the first portion 21aa is joined to the inner surface of the front film 1 on the other side of the first base 21a. The female member 22 has a belt-shaped second base 22a in a front view and a female fitting portion 22b on one side of the second base 22a. The second base 22a has a first portion 22aa near the first edge 4 and a second portion 22ab near the second edge 5, and the first portion 22aa is bonded to the inner surface of the front film 1.

The details of the male fitting portion 21b and the female fitting portion 22b will be described. Figures 4(b) and (c) are cross-sectional views of the fitting 20 corresponding to Figure 4(a). Of these, Figure 4(b) is a form in which there is no gap between the outer protrusion 21bb of the male fitting portion 21b and the inner protrusion 22bb of the female fitting portion 22b in the direction in which the front surface film 1 and the back surface film 2 face each other. Also, Figure 4(c) is a form in which there is a gap between the outer protrusion 21bb of the male fitting portion 21b and the inner protrusion 22bb of the female fitting portion 22b in the direction in which the front surface film 1 and the back surface film 2 face each other, and the outer protrusion 21bb of the male fitting portion 21b and the inner protrusion 22bb of the female fitting portion 22b are separated by a predetermined distance D. The male fitting portion 21b according to this embodiment has one column 21ba and two sets of outer protrusions 21bb that are protrusions that extend in a direction intersecting the extension direction of the column 21ba. The female fitting portion 22b according to this embodiment has two sets of column 22ba and inner protrusions 22bb that are protrusions that extend in a direction intersecting the extension direction of the column 22ba. In particular, in the fitting device 20 shown in FIG. 4(c), the outer protrusions 21bb of the male fitting portion 21b and the inner protrusions 22bb of the female fitting portion 22b are separated by a predetermined distance D or more in the direction in which the front film 1 and the back film 2 face each other. This increases the space between the male fitting portion 21b and the female fitting portion 22b, making it easier for the male fitting portion 21b and the female fitting portion 22b to come out of engagement when the pressure in the housing portion 11 increases.

As shown in FIG. 1 and FIG. 4(a), the front film 1 has a slit 8 penetrating the front film 1 so as to extend in a direction along the first edge 4. In the pouch according to this embodiment, either the front film 1 or the back film 2 is used as the slit forming surface, and the slit 8 is formed only on the slit forming surface. Since the "front" and "back" of the front film 1 and the back film 2 are relative, either may be used as the slit forming surface, but in this embodiment, the front film 1 is used as the slit forming surface. The slit 8 is formed in a direction connecting the third edge seal portion 16 and the fourth edge seal portion 17. Specifically, as shown in FIG. 1, the slit 8 is formed from the inner edge of the third edge seal portion 16 to the inner edge of the fourth edge seal portion 17. Preferably, the extension direction of the slit 8 is parallel to the first edge portion 4 and the second edge portion 5. Between the inner edge of the third edge seal portion 16 and the inner edge of the fourth edge seal portion 17, the front film 1, which is the slit forming surface, is divided into a first portion 1a on the first edge portion 4 side and a second portion 1b on the second edge portion 5 side by the slit 8. The front film 1 has a slit 8 formed therethrough so as to extend in a direction along the first edge portion 4. As shown in FIG. 4(a), when the male member 21 and the female member 22 are mated, the opening leading from the slit 8 to the storage portion 11 is closed and the pouch is resealed.

The fitting 20 formed along the first edge 4 and slit 8 can be used as a zipper, making it possible to open and reseal the storage section 11. The joining surface of the fitting 20 is not limited to the embodiment shown in Figs. 1 and 4(a), and the first portion 21aa of the first base 21a and the first portion 22aa of the second base 22a may be joined to the inner surface of the back film 2, which serves as the slit forming surface.

The material of the fitting 20 can be a resin that is compatible with the sealant layer of the laminated film used as the front film 1, back film 2, and bottom film 3. As shown in FIG. 4, the fitting 20 is composed of a male member 21 and a female member 22, and both the male member 21 and the female member 22 are joined to the inner surface of the front film 1 by heat sealing. At this time, a heat shield plate (not shown) is interposed between the male member 21 and the female member 22 to prevent the male member 21 and the female member 22 from thermally fusing.

In this embodiment, the first base 21a and the second base 22a are formed from one continuous member (tape). This continuous member has a thin portion 20b, and the thin portion 20b is folded back closest to the second edge 5 to form the end portion 20a closest to the second edge 5 of the fitting 20. This end portion 20a is the boundary between the first base 21a and the second base 22a.

At a predetermined position on the outer surface of the front film 1, a message indicating the presence of the fitting 20 and instructions on how to use the fitting 20 can be printed. For example, messages such as "Please close the zipper up to this point and place in the microwave" or "Please leave this part open when placing in the microwave" can be printed. Such messages are preferably formed on the second portion 1b of the front film 1.

There are no particular limitations on the shapes of the male fitting portion 21b and the female fitting portion 22b, so long as they are shapes that allow them to fit together. As described above, the male fitting portion 21b has one pillar portion 21ba and outward projections 21bb, 21bb that protrude in both directions intersecting the extension direction of the pillar portion 21ba. The female fitting portion 22b has two pillar portions 22ba, 22ba, and an inward projection 22bb for each pillar portion 22ba that protrudes toward the inside of the female fitting portion 22b.

In the fitting device 20, the outer protrusion 21bb protrudes outward from the male fitting portion 21b, and the inner protrusion 22bb protrudes inward from the female fitting portion 22b. The corresponding outer protrusion 21bb and inner protrusion 22bb are positioned overlapping in the direction in which the male fitting portion 21b and the female fitting portion 22b face each other (the direction in which the front film 1 and the back film 2 face each other). Therefore, when attempting to disengage the male fitting portion 21b and the female fitting portion 22b, the corresponding outer protrusion 21bb and inner protrusion 22bb push against each other, so that a weak force is required to disengage the fitting.

In this embodiment, the shapes of the male fitting portion 21b and the female fitting portion 22b are designed so that the male fitting portion 21b and the female fitting portion 22b can be disengaged with a relatively weak force when the pressure inside the storage portion 11 increases. Specifically, as shown in FIG. 4(c), when the male fitting portion 21b and the female fitting portion 22b are engaged with each other, the distance D between the corresponding outer protrusion portion 21bb and the inner protrusion portion 22bb in the direction in which the male fitting portion 21b and the female fitting portion 22b face each other is formed to be a predetermined distance or more. Since the distance D between the corresponding outer protrusion portion 21bb and the inner protrusion portion 22bb is a predetermined distance or more, a space (gap) of a predetermined size is generated between the corresponding outer protrusion portion 21bb and the inner protrusion portion 22bb. By having a space of a certain size between the corresponding outer protrusion 21bb and inner protrusion 22bb, the pressure in this space increases when the pouch is heated. Then, a force acts on the outer protrusion 21bb and the inner protrusion 22bb in a direction away from each other from this space, making it easier for the male fitting portion 21b and the female fitting portion 22b to come out of engagement.

The distance D between the outer protrusion 21bb and the inner protrusion 22bb is preferably 0.3 mm or more and 1 mm or less. If the distance D is less than 0.3 mm, it is difficult for the engagement to come off due to the increase in pressure caused by heating, and if the distance D exceeds 1 mm, the engagement is likely to come off before sufficient heating. In particular, if the distance D between the outer protrusion 21bb and the inner protrusion 22bb is 0.3 mm or more, the inner engagement strength (described in detail later) of the male engagement part 21b and the female engagement part 22b against the force applied from the inside of the pouch is within a predetermined range. Therefore, when heated appropriately, the engagement between the male engagement part 21b and the female engagement part 22b will come off. The distance D between the outer protrusion 21bb and the inner protrusion 22bb is preferably set so that the inner engagement strength between the male engagement part 21b and the female engagement part 22b is 3 N or more and 40 N or less.

In the example of FIG. 5, after the contents (such as seasonings) are filled into the storage section 11, it is sealed with the first edge seal section 14. Then, by disengaging the fitting 20, an opening from the slit 8 to the storage section 11 is created, allowing the user to add seasonings through the slit 8.

As shown in FIG. 4(c), in this embodiment, the distance D between the outer protrusion 21bb and the inner protrusion 22bb is adjusted so that the inner fitting strength, which is the fitting force between the male fitting portion 21b and the female fitting portion 22b, is set to 3N or more and 40N or less. Therefore, when the pressure inside the storage portion 11 increases due to heating of the pouch, the inside of the storage portion is sufficiently steamed, and then the male fitting portion 21b and the female fitting portion 22b are disengaged, and steam escapes to the outside. In this way, by providing the fitting device 20, which is the opening and closing mechanism, as a steam venting mechanism, it is no longer necessary to provide a steam venting mechanism in the seal portion that joins the films together. Therefore, it is no longer necessary to use an easy peel or a sealant layer that is easily retracted in the laminated film used as the front film 1, the back film 2, and the bottom film 3. Therefore, it is possible to provide a pouch that is superior in strength to conventional pouches.

The first base 21a of the male member 21 that is joined to the front film 1 is connected to the male fitting portion 21b at the center in the direction connecting the first edge portion 4 and the second edge portion 5, and is a rib that is not connected to the male fitting portion 21b on the first edge portion 4 side from this center portion and on the second edge portion 5 side from the center portion. In reality, only this rib portion is joined to the front film 1, but in the example of Figure 4, to avoid cluttering the drawing, the entire first portion 21aa of the first base 21a is shown in contact with the inner surface of the front film 1.

As an example, the length L4 of the first portion 21aa in the direction connecting the first edge 4 and the second edge 5 can be 13 mm, with the connecting portion with the male fitting portion 21b being 3 mm, and the ribs on the first edge 4 side and the second edge 5 side being 5 mm each.

The fitting 20 has an opening that is simply closed by the engagement of the male member 21 and the female member 22; it is not joined and sealed. Therefore, when the pressure inside the storage section 11 increases and pressure is applied to the fitting 20, the male member 21 and the female member 22 become disengaged, creating an opening with the slit 8 as the opening end, and steam can escape through the slit 8.

<Film details>
A laminated film can be used as the front film 1, the back film 2, and the bottom film 3 of the pouch. The laminated film is a laminate including at least a base layer and a sealant layer from the outside. For example, the laminated film is formed by laminating a base layer, a printed layer, other layers (e.g., a barrier layer), and a sealant layer in this order from the outside. The printed layer and other layers are not essential. An adhesive layer can also be used to laminate these layers. The sealant layer is a layer that constitutes the innermost surface of the pouch. The pouch according to this embodiment is required to be resistant to heat. For this reason, the base layer is preferably made of a material having heat resistance. For example, polyester films such as polyethylene terephthalate and polybutylene terephthalate, polyamide films such as nylon, polypropylene films, etc. can be used as the material of the base layer. The thickness is about 10 μm to 50 μm. The base layer is preferably biaxially stretched.

The laminated film may also have multiple substrate layers. The multiple substrate layers may include a first substrate layer and a second substrate layer. The first substrate layer and the second substrate layer may be selected from the above materials in appropriate combination. For example, polyethylene terephthalate may be used as the first substrate layer, which is the outermost layer, and polyamide may be used as the second substrate layer, which is the inner layer (sealant layer side). The second substrate layer is stretched from one side edge to the other side edge. For example, "Emblem (registered trademark) NC" manufactured by Unitika Ltd., which contains MXD (metaxylenediamine) having excellent barrier properties, may be used as the second substrate layer. In addition, polyester such as "Emblet (registered trademark) PC" manufactured by Unitika Ltd. or "Emblet (registered trademark) PCBC" manufactured by Unitika Ltd. may be used as the second substrate layer. The first substrate layer and the second substrate layer may be laminated, for example, by a dry lamination method.

The printing layer is provided to display the product contents, to impart an aesthetic look, and to display cut portions. The printing layer is formed from printing ink containing a binder and a pigment. The sealant layer is placed on the side of the laminated film that will be the innermost side of the container when the film is made into a pouch. Polyolefin resins such as polyethylene, polypropylene, ethylene-vinyl acetate copolymer, and ethylene-propylene block copolymer can be used as the material for the sealant layer. The thickness of the sealant layer is 30 μm or more and 150 μm or less. It is preferable that the sealant layer is unstretched.

The laminated film may include other layers. The other layers may be provided on the outside of the base layer, or between the base layer and the sealant layer. As the other layers, appropriate ones are selected according to the required functions, such as water vapor and other gas barrier properties, light shielding properties, etc. For example, when the other layer is a gas barrier layer, a vapor deposition layer of a metal oxide such as aluminum oxide or an inorganic oxide such as silicon oxide is provided. The vapor deposition layer may be laminated on the base layer, or may be vapor deposited on the sealant layer. In addition, a resin layer having gas barrier properties, such as ethylene-vinyl alcohol copolymer (EVOH), polyvinylidene chloride resin (PVDC), or aromatic polyamide such as nylon MXD6, may be provided. Each layer can be laminated using a dry lamination method, a melt extrusion method, or the like.

Specific examples of the layer structure of a laminated film with one base layer include the following. Of course, this is not limited to the following.

・Transparent vapor-deposited stretched nylon (ONY) 15 μm / printing layer (ink) / adhesive / linear low-density polyethylene (LLDPE) 60 μm (total thickness 79 μm)
・Transparent vapor-deposited polyethylene terephthalate (PET) 12 μm / printing layer / adhesive / LLDPE 80 μm (total thickness 96 μm)
Furthermore, examples of a substrate having two layers include the following.
・Transparent vapor-deposited PET 12 μm/printed layer/adhesive/ONY 15 μm/adhesive/LLDPE 50 μm (total thickness 81 μm)
・ONY 15μm/printed layer/adhesive/transparent vapor-deposited PET 12μm/adhesive/LLDPE 80μm (total thickness 111μm)
・Transparent vapor-deposited PET 12 μm/printed layer/adhesive/ONY 15 μm/adhesive/CPP 50 μm (total thickness 81 μm)
PET 12 μm / printing layer / adhesive / transparent vapor deposition PET 12 μm / adhesive / CPP 60 μm (total thickness 88 μm)

The substrate layer with the transparent vapor deposition also functions as a barrier layer. There are no particular limitations on the total thickness of the laminated film, but it is preferably 75 μm or more and 130 μm or less to allow for adequate vapor release.

<Production Method>
A method for manufacturing a pouch according to this embodiment as shown in Fig. 1 will be described. Fig. 6 is a cross-sectional view of a film constituting the fitting 20, which is an opening and closing mechanism. As described above, the fitting 20 is formed by folding back the male member 21 and the female member 22 at the end 20a of the thin-walled portion 20b. The fitting 20 is formed as a single film in which the male member 21 and the female member 22 are continuous. This single film may have a single layer structure, or may be a laminated film made up of multiple layers.

First, prepare a fitting 20 as shown in FIG. 6. Specifically, a resin molding process is performed to form a male member 21 and a female member 22 at predetermined positions, and a thin portion 20b is formed between the male member 21 and the female member 22. The thin portion 20b can be formed by creasing or by extrusion molding using a mold. Next, prepare a front film 1, and form a slit 8 at a predetermined position on the front film. Then, fold back the fitting member 20A with a predetermined position on the thin portion 20b as the end 20a. Furthermore, the first portion 21aa of the first base 21a and the first portion 22aa of the second base 22a are heat-sealed at positions sandwiching the slit 8, and the fitting 20 is joined to the front film 1.

Next, as shown in Figure 3, the back film 2 and bottom film 3 are placed in a predetermined position relative to the front film 1. After this, the bottom seal portion 15, the third edge seal portion 16, and the fourth edge seal portion 17 are formed by heat sealing. The first edge portion 4 side is left unsealed, and an opening for filling the contents is formed. By cutting between the third edge seal portion 16 and the fourth edge seal portion 17, each individual piece is separated from the continuous film, and a pouch as shown in Figures 1 and 2 is obtained.

Pouches such as those shown in Figures 1 and 2 may be sold or distributed with the first edge 4 unsealed. Furthermore, after the contents are placed in the storage section 11 through the opening of the unsealed first edge 4, the first edge seal section 14 is formed on the first edge 4 to seal the pouch. This results in a sealed pouch such as that shown in Figure 5. Note that in reality, the pouch is sealed with the contents placed therein, but in Figure 5, the contents are omitted for convenience of illustration.

<How to use>
A method of using the pouch according to the present embodiment as shown in Fig. 5 will be described. In the sealed state, the first content is contained in the storage section 11. In this state, a finger is inserted through the slit 8 formed in the front film 1, and the second portion 1b, which is a portion of the front film 1 closer to the second edge portion 5 than the slit 8, is pulled outward to release the engagement between the male member 21 and the female member 22 of the fitting device 20. Furthermore, due to this pulling force, the male member 21 and the female member 22 are separated at the end 20a located at the thin portion 20b of the fitting device 20. Fig. 8 is a cross-sectional view of the pouch in a state where it has been opened by the fitting device 20, which is an opening/closing mechanism. As shown in Fig. 8, the male member 21 and the female member 22 are separated, and the storage section 11 is connected through the slit 8, the pouch is opened, and food material can be introduced from the outside. Then, water or seasoning is added as a second content from the slit 8 into the storage section 11, which contains contents such as solids, dried foods (dried noodles, dried ingredients, powdered seasonings, dried fruits), and frozen foods. The pouch is then resealed. That is, the male member 21 and the female member 22 are fitted together to close the opening connected to the slit 8.

After pouring in the second contents (water and seasonings) and resealing, the container is placed in a microwave oven with the second edge 5 facing downward. Heating is then performed in the microwave oven. This causes the temperature inside the container 11 to rise, evaporating the water inside the container 11 and increasing the pressure inside the container 11.

When the pressure inside the storage section 11 increases, the front film 1 and the back film 2 bulge outward due to the force they receive from inside the storage section 11. At this time, in the storage section 11, a force is applied from the center of the storage section 11 toward the outside to the third edge seal section 16, the fourth edge seal section 17, the first bottom seal section 15a, and the fitting device 20, which is the opening and closing mechanism, which define the storage section 11. In particular, as shown in FIG. 4(c), when the distance D between the outer protrusion 21bb and the inner protrusion 22bb is equal to or greater than a predetermined distance, the pressure in the space between the outer protrusion 21bb and the inner protrusion 22bb increases, and a force acts in the direction of disengaging the male fitting section 21b and the female fitting section 22b.

From this state, as heating continues in the microwave oven and the pressure inside the storage section 11 increases, the front film 1 and the back film 2 expand further outward due to the force they receive from the storage section 11. Here, in the pouch of this embodiment, if the distance D between the outer protrusion 21bb and the inner protrusion 22bb is equal to or greater than a predetermined distance, the pressure in the space between the outer protrusion 21bb and the inner protrusion 22bb increases, and a force acts in the direction of disengaging the male fitting section 21b and the female fitting section 22b. Then, after sufficient heating, the male fitting section 21b and the female fitting section 22b are disengaged, and steam escapes. Even if the distance D between the outer protrusion 21bb and the inner protrusion 22bb is equal to or greater than a predetermined distance and a space is provided, the male fitting section 21b and the female fitting section 22b are engaged, so there is a certain degree of inner fitting strength. This allows the storage section 11 to remain filled with steam for a long time, allowing the food to be thoroughly steamed.

After being heated for a predetermined time, the food has absorbed the appropriate amount of moisture and has the appropriate elasticity and texture. As described above, the method of using the pouch according to this embodiment includes the steps of opening the fitting 20, which is the opening and closing mechanism, to open the pouch, then placing the second contents through the slit 8, and closing the fitting 20, which is the opening and closing mechanism, and then heating using a microwave oven. This makes it possible to easily cook the food contents.

Example 1
A transparent vapor-deposited PET film having a thickness of 12 μm was used as the substrate layer, and a non-oriented polypropylene (CPP) film having a thickness of 60 μm was used as the sealant layer. Specifically, a printed layer was first formed on the inner surface of the transparent vapor-deposited PET film having a thickness of 12 μm, which was the substrate layer. The printed layer may also include a print indicating the presence of the fitting 20 and the method of using the fitting 20. Then, a 15 μm-thick stretched nylon (ONY) film was bonded to the surface of the printed layer side via an adhesive layer. Furthermore, a 60 μm-thick CPP film was bonded to the surface of the ONY film side via an adhesive layer. As a result, a packaging material was obtained that was a laminated film having a layer structure of transparent vapor-deposited PET/printed layer/adhesive layer/ONY 15 μm/adhesive layer/CPP 60 μm. The adhesive layer was a cured product of an acrylic polyol and an isocyanate compound.

The obtained laminated film, which is the packaging material, was cut to 160 mm x 160 mm to form the front film 1 and the back film 2. Next, the laminated film was cut to 160 mm x 70 mm to form the bottom film 3. Furthermore, a fitting 20 made of polypropylene compatible with the sealant layer CPP was prepared. The width L4 of the fitting 20 was 13 mm. The distance D between the outer protrusion 21bb and the inner protrusion 22bb in this fitting 20 was 0.35 mm. Then, a heat shield plate (not shown) was interposed between the male member 21 and the female member 22, and the first part 21aa of the first base 21a and the first part 22aa of the second base were heat-sealed to the inner side of the front film 1. The first portion 21aa of the first base portion 21a is joined to a position closer to the first edge portion 4 than the slit 8, and the first portion 22aa of the second base portion 22a is joined to a position closer to the second edge portion 5 than the slit 8.

Next, the front film 1, the back film 2, and the bottom film 3 were used to form the pouch according to the first embodiment shown in FIG. 1 (the pouch without the first edge seal portion 14). After that, 150 g of mapo tofu base was filled into the storage portion 11 from the first edge 4 side.

Then, the first edge seal portion 14 was formed to form the pouch shown in FIG. 5. The seal width of the first edge seal portion 14 was 10 mm, the seal width at the position where the distance between the first bottom seal portion 15a and the second edge portion 5 was the shortest was 5 mm, and the seal widths of the third edge seal portion 16 and the fourth edge seal portion 17 were 6 mm. The distance H1 from the fold-in portion 3a to the second edge portion 5 of the pouch was 35 mm, the distance H2 from the first edge portion 4 to the slit 8 was 30 mm, the distance H3 between the first edge portion 4 and the second edge portion 5 (pouch height) was 160 mm, and the distance W between the third edge portion 6 and the fourth edge portion 7 (pouch width) was 160 mm.

Example 2
A pouch according to this embodiment was formed in the same manner as in Example 1, except that a fitting 20 in which the distance D between the outer protrusion 21bb and the inner protrusion 22bb was set to 0.5 mm was used.

Example 3
A pouch according to this embodiment was formed in the same manner as in Example 1, except that a fitting 20 in which the distance D between the outer protrusion 21bb and the inner protrusion 22bb was set to 0.7 mm was used.

<Heating experiment>
For the pouches of the examples and the comparative examples, the pouches were further frozen after containing 150 g of mapo tofu base, which is the first content. This is to meet the conditions for use as a frozen meal kit. The pouch according to the present embodiment has a slit 8 formed in the front film 1, and when the pouch is frozen and distributed, there is little possibility of leakage of the content. After freezing, a heating experiment was performed. First, 150 g of the mapo tofu base in a frozen state was heated at 500 W for 1 minute to semi-thaw it. After semi-thawing, the pouch was opened to put in the tofu, which is the second content. Specifically, a finger was inserted through the slit 8 formed in the front film 1, and the portion of the front film 1 closer to the second edge 5 than the slit 8 was pulled outward to release the engagement between the male member 21 and the female member 22. Furthermore, due to this pulling force, the male member 21 and the female member 22 were separated at the end 20a. As a result, the slit 8 communicates with the storage section 11, and the pouch is opened. Then, it becomes possible to insert food ingredients from the outside.

The pouch was then allowed to stand on its own, and 200 g of cut tofu was added to the storage section 11 containing the mapo tofu base. The pouch was then resealed by fitting the male member 21 and female member 22 together to close the opening. The pouch was then placed in a microwave oven with the second edge 5 facing downwards, and heated at 500 W for 3 minutes. After heating, the pouch was visually inspected for the degree of expansion to see whether steam had escaped properly, and the engagement between the male member 21 and female member 22 was visually inspected to see whether the engagement between the male member 21 and female member 22 had come loose. If the engagement had come loose, it was evaluated as ◯, and if the engagement had not come loose, it was evaluated as ×.

In addition, tests were conducted on the inner fitting strength of the fitting 20 used in the embodiment, comparative examples 1 and 2. The inner fitting strength is the strength against the force applied from the inside of the pouch. Specifically, the test was conducted by preparing a male member 21 in which the first base 21a extends S1 mm in the extension direction of the male fitting portion 21b of the male member 21 of the fitting 20 and S2 mm in the direction perpendicular to the extension direction of the male fitting portion 21b, and a female member 22 in which the second base 22a extends S1 mm in the extension direction of the female fitting portion 22b and S2 mm in the direction perpendicular to the extension direction of the male fitting portion 21b, and forming a test piece S in which the male fitting portion 21b and the female fitting portion 22b are fitted together. In this tensile test, S1 = 50, S2 = 40. FIG. 7(a) is a plan view of the test piece S with the first base portion 21a and the second base portion 22a spread out.

As shown in FIG. 7(b), with the first part of the female member 22 fitted with the male member 21 and the female member 22, the first base 21a and the second base 22a of the test piece S were pulled by a pair of chucks 40, 40 using a tensile testing device, and a tensile load was applied until the male member 21 and the female member 22 were disengaged. The maximum load during that period was the inner fitting strength (unit: N/50 mm). The width of the test piece S was 50 mm. The tensile testing device used was the "Tensilon Universal Testing Machine RTF" manufactured by Orientec Co., Ltd., with the chuck distance L: 20 mm and the tensile test speed: 500 mm/min. The inner fitting strength was measured five times for each example and comparative example, and the average value was also recorded. The evaluation results are shown in Table 1.

As shown in Table 1, in Example 1, in which the inner fitting strength is relatively weak, the fitting was released due to the pressure increased by heating, and the internal steam escaped to the outside. In Examples 2 and 3, in which the inner fitting strength is relatively strong, the fitting force was stronger than the pressure increased by heating, the fitting did not come off, and the internal steam did not escape to the outside. If the fitting does not come off, there is a problem that the internal pressure becomes too high, but it can be used by adjusting the heating time. In order to ensure that the fitting comes off with an appropriate pressure when heated, it is preferable to set the upper limit of the inner fitting strength in the range of more than 5.8 N in Example 1 and less than 45.0 N in Example 3. Specifically, it is preferable that the upper limit of the inner fitting strength is 40 N. Also, in order to prevent the fitting from coming off during normal use, it is preferable that the lower limit is 3 N. Therefore, it is preferable that the inner fitting strength is 3 N or more and 40 N or less.

Although the preferred embodiment of the present invention has been described above, the present invention is not limited to the above embodiment and various modifications are possible. For example, in the above embodiment, a bottom film 3 is provided and a bottom gusset portion 9 is provided, but it is not necessary to provide a bottom gusset portion 9, and the container may be in the form of a so-called flat pouch in which the storage portion 11 is formed by the front film 1 and the back film 2.

In the above embodiment, the front film 1 and the back film 2 are defined as the "front" and "back" for ease of explanation. The front film 1 and the back film 2 are symmetrical to each other, so either may be the "front" and either may be the "back". The third edge portion 6 and the fourth edge portion 7 are also symmetrical to each other, so either may be the third edge portion and either may be the fourth edge portion.

In the above embodiment, the front film 1, the back film 2, and the bottom film 3 are each formed as three separate films to form the pouch, but they may be formed from two or one film. For example, one film in which the front film 1, the bottom film 3, and the back film 2 are connected may be used, or two films in total may be used, including the film forming the front film 1 and the film in which the back film 2 and the bottom film 3 are connected. When one film in which the front film 1, the bottom film 3, and the back film 2 are connected is used, the bottom gusset portion 9 can be formed by folding the single film twice at the second edge 5 and once at the fold-in portion 3a without forming a seal portion at the second edge 5. In this case, the pouch is sealed by filling the pouch with the contents from the opening on the first edge 4 side and then forming the first edge seal portion 14.

1: Front film 2: Back film 3: Bottom film 3a: Fold-in portion 3f: First portion of bottom film 3g: Second portion of bottom film 4: First edge portion 5: Second edge portion 6: Third edge portion 7: Fourth edge portion 8: Slit 9: Bottom gusset portion 9a: First pleat portion 9b: Second pleat portion 11: Storage portion 14: First edge seal portion 14a: First edge seal portion 15: Bottom seal portion 15a: First bottom seal portion 15b: Second bottom seal portion 16: Third edge seal portion 17: Fourth edge seal portion 20: Fitting (opening/closing mechanism)
20a... (of the fitting) end 20b... (of the fitting) thin portion 21... male member 21a... first base 21aa... first portion (of the first base 21a) 21ab... second portion (of the first base 21a) 21b... male fitting portion 21ba... column portion (of the male fitting portion 21b) 21bb... outer protrusion portion (of the male fitting portion 21b) 22... female member 22a... second base 22aa... first portion (of the second base 22a) 22ab... second portion (of the second base 22a) 22b... female fitting portion 22ba... column portion (of the female fitting portion 22b) 22bb... inner protrusion portion (of the female fitting portion 22b)

Claims (2)

A pouch having a storage portion between a front film and a back film,
A first edge portion;
a second edge portion opposite the first edge portion;
a third edge and a fourth edge extending between the first edge and the second edge;
an opening/closing mechanism formed between the first edge portion and the second edge portion and closer to the first edge portion,
A third edge seal portion and a fourth edge seal portion are formed in the third edge portion and the fourth edge portion along a direction in which the third edge portion and the fourth edge portion extend,
a slit is formed from an inner edge of the third edge seal portion to an inner edge of the fourth edge seal portion, with one of the front surface film and the back surface film being a slit forming surface;
The opening and closing mechanism includes a first member and a second member that fit together,
The first member and the second member are joined at positions on the slit forming surface across the slit,
The first and second members are a single continuous member that is folded back with a thin portion of the continuous member inward to form an end portion. The pouch according to claim 1, wherein the inner fitting strength of the opening/closing mechanism is 3N or more and 40N or less.