Pouch

Abstract

To provide a pouch capable of improving accuracy of bending a film.SOLUTION: In a pouch 10 including a film bending part 50, a film weakening part 60 is formed in a film, and at least a part of the film weakening part 60 is formed on the film bending part 50.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a pouch having a film bent portion where the film is bent.

Background Art

[0002] Conventionally, as a container for storing cooked or semi-cooked foods, a pouch formed in a bag shape by heat-sealing a resin film at a predetermined location has been widely used.

[0003] Also, as one type of such a pouch, a pouch having a film bent portion, such as a so-called branched pouch having a pouch branch portion formed to protrude from the front side film constituting the pouch body, is generally known (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, in such a pouch having a film bent portion, due to the complexity of its shape, it is difficult to handle the film, and it is difficult to ensure the bending accuracy of the film, such as it being difficult to stabilize the bending position of the film during pouch manufacturing.

[0006] Therefore, the present invention aims to solve these problems and provide a pouch with a simple configuration that can improve the bending accuracy of the film.

Means for Solving the Problems

[0007] The present invention relates to a pouch having a film bend portion formed by folding a film, wherein a film weakening portion is formed in the film, and at least a portion of the film weakening portion is formed on the film bend portion. The pouch comprises a pouch body having a contents storage section and a pouch branch section formed protruding outward from the outer film constituting the pouch body, and is a microwave oven pouch equipped with a steam venting mechanism that releases steam from the contents storage section to the outside through a steam vent formed in the pouch branch section when heated, the pouch branch section consists of a branch film folded at its upper end side bend, the lower end of the branch film is connected to the outer film, the branch film has a steam venting penetration formed through it in the film thickness direction, at least a part of the steam venting penetration is formed on the upper end side bend as the film bend section and functions as the film weakening section, the steam venting mechanism has a communication start section that connects the contents storage section and the steam vent when heated, and the steam venting machine The structure has a main steam vent formed closer to the planned communication start portion than the steam vent penetration portion, the steam vent penetration portion is formed as an auxiliary steam vent, the branch film has a branch back film portion arranged opposite to the front film portion and a branch front film portion arranged on the front side of the branch back film portion, the steam vent mechanism has a flap piece as the main steam vent portion, partitioned by a slit formed in one of the branch front film portion or the branch back film portion at the steam opening portion, and a steam vent hole formed in the other of the branch front film portion or the branch back film portion at the steam opening portion such that at least a part of the flap piece overlaps the flap piece in the front-back direction, the branch film has an overlapping peripheral portion at the periphery of the steam vent hole, which overlaps a part of the flap piece in the front-back direction This solves the aforementioned problem. Furthermore, the present invention relates to a microwave oven pouch having a film bend portion formed by folding a film, wherein the film has a film weakening portion formed thereon, at least a part of which the film weakening portion is formed on the film bend portion, the pouch comprises a pouch body having a contents storage portion and a pouch branch portion formed protruding outwards from the outer film constituting the pouch body, and is equipped with a steam venting mechanism that releases steam from the contents storage portion to the outside through a steam vent formed in the pouch branch portion when heated, the pouch branch portion consists of a branch film bent at its upper end bend portion, the lower end of the branch film is connected to the outer film, the branch film has a steam venting penetration formed penetrating in the film thickness direction, at least a part of which is the upper end as the film bend portion The problem is solved by having a main steam vent formed on the bent end portion which functions as the film weakening portion, having a planned communication start portion which connects the contents storage portion and the steam release portion when heated, having a main steam vent formed closer to the planned communication start portion than the steam vent penetration portion, having the steam vent penetration portion which is formed as an auxiliary steam vent, having a branch back film portion which is arranged opposite to the front film portion which is arranged opposite to the branch back film portion which is arranged on the front side of the branch back film portion which is arranged opposite to the branch back film portion which is arranged opposite to the branch front film portion which is arranged opposite to the branch back [Effects of the Invention]

[0008] Claim 1, Claim 2 According to the invention, by forming at least a portion of the film weakening portion on the film bending portion, it becomes easier to bend the film at the planned location of the film bending portion during pouch manufacturing, thereby improving the bending accuracy of the film and improving pouch productivity. Furthermore, according to the inventions of claims 1 and 2, by utilizing the steam venting holes for releasing steam during heating as film weakening sections, it is possible to perform film folding with high precision at the planned locations of the upper end folding sections, which serve as film folding sections, while avoiding structural complexity, thereby improving production efficiency. Furthermore, according to the inventions of claims 1 and 2, since the steam venting penetration that functions as a film weakening portion is formed as an auxiliary steam vent, the requirements for the steam venting function of the steam venting penetration are reduced, making it easier to achieve both the steam venting function and the film weakening function of the steam venting penetration. Furthermore, according to the invention of claim 1, the branched film has an overlapping peripheral portion that is arranged to overlap a part of the flap piece in the front-back direction at the periphery of the steam vent hole. This overlapping peripheral portion controls the movement of the flap piece, preventing it from getting caught on the inner edge of the steam vent hole. As a result, the flap piece can be opened properly during heating, allowing steam to be released appropriately. Furthermore, according to the invention of claim 2, by forming a steam vent hole in the film portion on the back of the branch, even if the contents leak out from the steam vent hole, the leaked contents can be contained between the pouch body and the pouch branch, preventing the contents from adhering to the outside of the pouch where they are easily visible from the outside. Moreover, by arranging the film portion on the back of the film portion on the front of the branch where the flap piece is formed on the back of the film portion on the back of the branch where the steam vent hole is formed, it is possible to guide the film fold peak, which is formed on the front film of the pouch body to become convex toward the front due to the expansion of the pouch body during heating, to be formed at the back of the flap piece. As a result, the convex film fold peak pushes up the flap piece from the back, making it easier for the flap piece to open during heating.

[0009] Claim 3 According to the invention, by forming both ends of the slit constituting the film weakening portion on the film bending portion, the slit can function as a guide when bending the film at the planned location of the film bending portion. Therefore, the film bending portion can be formed with precision using a simple structure. Claim 4 According to the invention, the middle portion of the slit is formed in a straight line, and the entire slit is formed along the film bending portion, so that the entire slit constituting the film weakening portion can function as a guide when bending the film. Claim 5According to the invention, the middle portion of the slit is formed so as to connect the two ends of the slit in a way that partitions the movable piece, without intersecting a virtual line that linearly connects the two ends of the slit. This allows the slit to function as a guide when folding the film at the planned location of the film bending portion, while also ensuring a good amount of steam is discharged when the slit is used as a part for releasing steam during heating. Claim 6 According to the invention, the distance between both ends of the slit is set to be greater than the width of the middle part of the slit in a direction perpendicular to the extending direction of the film bending portion, thereby enabling the effect of stabilizing the film bending position by the film weakening portion to be effectively realized. Claim 7 According to the invention, by forming the outer edge of the hole constituting the film weakening portion to overlap over a portion of the film bending portion, the film can be folded accurately at the planned location of the upper end bending portion. Claim 8 According to the invention, the width of the portion of the outer edge of the film weakening portion that overlaps with the film bending portion in the extending direction of the film bending portion is set to be larger than the width of the film weakening portion in a direction perpendicular to the extending direction of the film bending portion, thereby enabling the effect of stabilizing the film bending position by the film weakening portion to be effectively demonstrated. Claim 9 According to the invention, the film weakening portion is formed in a position that overlaps with the seal portion when the pouch is viewed from above, and in a position where the film weakening portion is isolated from the contents storage portion by the seal portion. Therefore, there is no need to consider leakage of contents due to the formation of the film weakening portion, and a degree of design freedom for the film weakening portion can be ensured, such as by adopting a slit that penetrates in the film thickness direction as the film weakening portion. [Brief explanation of the drawing]

[0010] [Figure 1] An explanatory diagram showing a pouch related to one embodiment of the present invention. [Figure 2]Explanatory drawing showing the flap piece and the steam vent hole as the center. [Figure 3] Explanatory drawing explaining the relationship between the flap piece and the steam vent hole. [Figure 4] Explanatory drawing explaining the film mountain fold top. [Figure 5] Explanatory drawing showing a modified example of the flap piece and the steam vent hole. [Figure 6] Explanatory drawing showing various modified examples of the steam vent through part as the film weakening part. [Figure 7] Explanatory drawing showing a modified example of the film bending part where the film weakening part is formed. [Figure 8] Explanatory drawing showing a modified example of the steam vent mechanism.

Mode for Carrying Out the Invention

[0011] Hereinafter, the pouch 10 according to an embodiment of the present invention will be described based on the drawings.

[0012] First, as shown in FIG. 1, the pouch 10 is formed into a bag shape by forming a bag-making seal part 11 obtained by thermally bonding a resin film at a predetermined position, and the content such as food is accommodated in the inner content accommodating part 12.

[0013] As shown in FIG. 1, the pouch 10 includes a film bending part 50 (a bending process for maintaining the bent state is performed) where the film is bent, and a film weakening part 60 designed to make the film strength at the formation position weaker than the peripheral part is formed on the film, and at least a part of this film weakening part 60 is formed on the film bending part 50.

[0014] Hereinafter, the specific configuration of the pouch 10 will be described.

[0015] As shown in Figure 1, the pouch 10 of this embodiment is configured as a so-called branched pouch, comprising a pouch body 20 having a contents storage section 12 and a pouch branch section 30 formed to protrude outward from the outer film 21 constituting the pouch body 20.

[0016] As shown in Figure 1, the pouch body 20 has a front film 21 and a back film 22 that are overlapped in the front-back direction, and is constructed in a bag shape by forming a bag-making seal portion 11 (top seal portion 11a, side seal portion 11b) by heat-sealing predetermined parts of these films 21 and 22 together.

[0017] As shown in Figure 1, the pouch branching portion 30 is formed as a part that protrudes outward from the front film 21 of the pouch body 20, extending across the entire area in the left-right direction of the pouch, midway along the vertical direction of the pouch. As shown in Figure 1, the pouch branch section 30 consists of a branch film 31 that is folded at its upper end, which is the upper end side bent section 32. The branch film 31 has a branch back side film section 42 that is positioned opposite the front side film 21 of the pouch body 20, and a branch front side film section 41 that is positioned on the front side of the branch back side film section 42.

[0018] The upper end bent portion 32 of the pouch branch portion 30 is formed as the above-described film bent portion 50, and as shown in Figure 1, in this embodiment it extends linearly along the left-right direction of the pouch, and in the upper end bent portion 32, the upper ends of the film portions 41 and 42 are formed continuously and integrally. Furthermore, as shown in Figure 1, film sections 41 and 42 are connected on both the left and right sides of the pouch branch section 30, and in this embodiment, the film sections 41 and 42 are heat-sealed at the side seal section 11b. Furthermore, as shown in Figure 1, the film portions 41 and 42 are not connected at the lower end portion 33 of the pouch branching portion 30. Furthermore, at the lower end 33 of the pouch branch portion 30, as shown in Figure 1, the lower end of the branch film 31 (i.e., the lower end of the branch front film portion 41 and the lower end of the branch back film portion 42) is connected to the front film 21. In this embodiment, the front film 21 and the branch film 31 are formed integrally (as a continuous film), but at least one of the lower ends of the branch front film portion 41 and the branch back film portion 42 may be formed separately from the front film 21 and connected by heat welding. Furthermore, a fold is formed (bent) at the connection point between the back-side film portion 42 and the front-side film 21 at the lower end 33 of the pouch branch portion 30. As a result, when the pouch branch portion 30 is unloaded (no force is being applied), the back-side film portion 42 of the branch is maintained facing the front-side film 21, as shown in Figure 1. Furthermore, no crease is formed (no bending is performed) at the connection point between the branched front film portion 41 and the front film 21 at the lower end 33 of the pouch branch portion 30.

[0019] The pouch 10 is configured as a microwave pouch equipped with a steam release mechanism 40 for releasing steam generated in the contents storage section 12 to the outside of the pouch when heated in a microwave oven. This steam release mechanism 40 is formed in the pouch branch section 30, as shown in Figure 1.

[0020] As shown in Figure 1, the steam venting mechanism 40 includes a branch front film portion 41 and a branch back film portion 42 arranged in overlapping order, a steam venting seal portion 43 formed by heat welding the branch front film portion 41 and the branch back film portion 42, a steam release portion 44 isolated from the contents storage portion 12 of the pouch body 20 by the steam venting seal portion 43, a flap piece 41b partitioned by a slit 41a formed in the branch front film portion 41 at the steam release portion 44, a steam venting hole 42a formed in the branch back film portion 42 at the steam release portion 44 such that at least a part of the flap piece 41b overlaps the flap piece 41b in the front-back direction, and a steam venting penetration portion 45 formed through the branch film 31 in the film thickness direction.

[0021] The steam venting mechanism 40 is configured such that, when heated in a microwave oven, the steam generated in the contents storage section 12 connects the contents storage section 12 and the steam release section 44 at the planned communication start section 43a, and the steam in the contents storage section 12 is released to the outside of the pouch through the flap piece 41b and steam release hole 42a formed in the steam release section 44, which serve as the main steam release (and also from the steam release penetration section 45, which serves as an auxiliary steam release depending on the steam ejection conditions).

[0022] Here, as shown in Figure 1, the flap piece 41b and the steam vent hole 42a are configured as a main steam vent, formed closer to the planned communication start point 43a of the steam vent seal portion 43 than to the steam vent penetration portion 45, and the steam vent penetration portion 45 is configured as an auxiliary steam vent, which functions as a point to discharge steam to the outside of the pouch when the steam discharge from the main steam vent is insufficient.

[0023] The flap piece 41b and steam vent hole 42a, which serve as the main steam vent, are described below.

[0024] First, the flap piece 41b formed on the branched front side film portion 41 is partially separated from the surrounding portion of the branched front side film portion 41 at the steam release portion 44 by a U-shaped slit 41a, as shown in Figures 1 and 2, and is a portion that moves toward the front side due to steam when heated. As shown in Figure 2, the flap piece 41b has a flap base end 41c which is part of the outer edge of the flap piece 41b, extends linearly along the lateral direction X, and is connected to the branched front side film portion 41, and a flap free end 41d which is part of the outer edge of the flap piece 41b, and is separated from the flap base end 41c in the vertical direction Y which is perpendicular to the lateral direction X. As shown in Figure 2, the flap piece 41b is formed such that the free end 41d of the flap is close to the planned communication start portion 43a of the steam vent seal portion 43, while the base end 41c of the flap is farther away. Here, the planned communication start section 43a is the part where the contents storage section 12 and the steam release section 44 are initially planned to be connected by the steam generated inside the contents storage section 12 during heating. In this embodiment, it is the part (seal peeling start section) designed to be the first to peel off the steam release seal section 43 by the steam generated inside the contents storage section 12 during heating.

[0025] Furthermore, as shown in Figure 2, a steam vent hole 42a is formed in the film portion 42 on the back side of the branch, penetrating the film portion 42 in the front-to-back direction. As shown in Figure 2, the branched back side film portion 42 has an overlapping peripheral portion 42b that is positioned on the periphery of the steam vent hole 42a, overlapping a part of the flap piece 41b in the front-back direction, in order to prevent the flap piece 41b from moving toward the branched back side film portion 42 (back side).

[0026] Next, the specific design of the flap piece 41b and the steam vent hole 42a, as well as the relationship between the flap piece 41b and the steam vent hole 42a, will be explained below.

[0027] First, as shown in Figures 2 and 5(a) and 5(f), it is preferable that the flap piece 41b (slit 41a) has a portion formed closer to the planned communication start portion 43a than the portion of the steam vent hole 42a that is closest to the planned communication start portion 43a. With this configuration, during heating, it is possible to open a portion of the flap piece 41b (move it toward the front) before steam begins to be released from the steam vent hole 42a. This ensures that the flap piece 41b is opened and prevents steam from being released only from the steam vent hole 42a.

[0028] Furthermore, regarding the position of the overlapping peripheral portion 42b, which is the part that overlaps the flap piece 41b in the front-back direction, it is preferable to set it so that the overlapping peripheral portion 42b overlaps in the front-back direction with at least a part of the portion of the flap free end 41d of the flap piece 41b that is furthest from the flap base end 41c in the vertical direction Y (the line portion or point portion of the flap free end 41d that has the largest distance from the flap base end 41c in the vertical direction Y), as shown in Figures 2 and 5(a)(b)(d)(e)(f). In this configuration, the overlapping peripheral portion 42b effectively prevents the entire flap piece 41b from moving toward the branched back side film portion 42. However, the specific position of the overlapping peripheral portion 42b is not limited to the above. For example, the overlapping peripheral portion 42b may be set to overlap only the lateral portion of the flap piece 41b in the lateral direction X, or, as shown in Figure 5(c), the overlapping peripheral portion 42b may be set to overlap only the flap base end 41c side of the flap piece 41b. Furthermore, the number of overlapping peripheral portions 42b is not limited to one location; multiple overlapping peripheral portions 42b may be formed at locations that are far apart from each other.

[0029] Furthermore, in the example shown in Figure 1, a branched back film portion 42 is positioned between the front film 21 of the pouch body 20 and the branched front film portion 41 on which the flap piece 41b is formed, and the branched back film portion 42 has a steam vent hole 42a formed such that at least a part of it overlaps the flap piece 41b in the front-back direction. With this configuration, as shown in Figure 4, it is possible to guide the film fold 21a, which is formed on the front film 21 of the pouch body 20 as a convex shape toward the front due to the expansion of the pouch body 20 during heating, to form on the back side of the flap piece 41b. As a result, the film fold 21a and the fold (a convex fold toward the front) that occurs in the branched back film portion 42 due to the formation of the film fold 21a push up the flap piece 41b from the back, making it easier for the flap piece 41b to open during heating. Furthermore, the term "film fold vertex 21" as used herein is not limited to the one formed in the center of the pouch in the left-right direction (or the center in the longitudinal direction of the pouch) as shown in Figure 4, but broadly refers to any convex portion toward the front side that results from the curvature (or fold) formed on the front film 21.

[0030] Furthermore, as shown in Figure 3 (and Figures 5(e)(f)), it is preferable that the steam vent hole 42a be formed such that the width W1 in the horizontal direction X (the width W1 in the widest part of the horizontal direction W1) is narrower than the vertical width H1 in the vertical direction Y (the vertical width H1 in the widest part of the vertical direction H1). With this configuration, it is possible to guide the film fold 21a to extend along the vertical direction Y near the flap piece 41b and the steam vent hole 42a. As a result, the film fold 21a extending in the vertical direction Y effectively pushes up the flap piece 41b, making it easier for the flap piece 41b to open during heating. Furthermore, forming the width W1 of the steam vent hole 42a narrower makes it easier to secure the height of the film fold top 21a and the fold that occurs in the branched back side film portion 42 due to the formation of the film fold top 21a.

[0031] Furthermore, as shown in Figure 3 (and Figures 5(a),(b),(c),(e),(f)), when viewed in the vertical direction Y, it is preferable to set the formation range R1 of the steam vent hole 42a in the horizontal direction X to fall within the formation range R2 of the flap piece 41b in the horizontal direction X. In this configuration, the film fold 21a extending in the vertical direction Y as described above effectively pushes up the flap piece 41b, making it easier for the flap piece 41b to open when heated.

[0032] Furthermore, as shown in Figure 3 (and Figures 5(b), (e), and (f)), it is preferable to set the width W2 of the flap piece 41b in the lateral direction X (the width W2 of the widest part of the width W2) to be wider than the width W1 of the steam vent hole 42a in the lateral direction X (the width W1 of the widest part of the width W1). In this configuration, the film fold 21a extending in the vertical direction Y as described above effectively pushes up the flap piece 41b, making it easier for the flap piece 41b to open when heated.

[0033] Furthermore, as shown in Figure 3 (and Figures 5(a), (c), and (f)), when viewed in the vertical direction Y, it is preferable that the overlapping peripheral portion 42b has a portion located within the steam vent hole 42a formation range R1 in the horizontal direction X (the portion indicated by reference numeral 42b-1 in Figure 3). In this configuration, the formation of the film's fold vertex 21a is utilized to push up the flap piece 41b from the back side with the overlapping peripheral edge 42b, making it easier for the flap piece 41b to open when heated.

[0034] Furthermore, the formation positions of the flap piece 41b and the steam vent hole 42a in the planar direction of the pouch 10 are as follows. First, it is preferable that the flap piece 41b and the steam vent hole 42a are formed at a position on the upper or lower side of the pouch body 20 in the vertical direction of the pouch, straddling a first imaginary line L1 that passes through the center of the pouch body 20 in the left-right direction and extends along the vertical direction of the pouch, as shown in the example in Figure 1, or at a position on the left or right side of the pouch body 20 in the left-right direction of the pouch, straddling a second imaginary line L2 that passes through the center of the pouch body 20 in the vertical direction and extends along the left-right direction of the pouch. In this configuration, the fold vertex 21a of the film is more likely to form on the back side of the flap piece 41b. That is, the areas around the first virtual line L1 and the second virtual line L2 are areas where the fold vertex 21a of the film is more likely to form due to the expansion of the pouch body 20 during heating, and by forming the flap piece 41b and steam vent hole 42a in the above-mentioned locations, the fold vertex 21a of the film is more likely to form on the back side of the flap piece 41b. More specifically, when forming the flap piece 41b at a position that straddles the first virtual line L1, it is even more preferable to form the flap piece 41b so that the base end 41c of the flap intersects the first virtual line L1, and when forming the flap piece 41b at a position that straddles the second virtual line L2, it is even more preferable to form the flap piece 41b so that the base end 41c of the flap intersects the second virtual line L2. Furthermore, when forming the flap piece 41b at a position that straddles the first imaginary line L1, it is preferable that the vertical direction Y of the flap piece 41b (the direction perpendicular to the horizontal direction X from which the flap base end 41c extends) coincides with (is parallel to) the up-down direction of the pouch (the direction from which the first imaginary line L1 extends). Also, when forming the flap piece 41b at a position that straddles the second imaginary line L2, it is preferable that the vertical direction Y of the flap piece 41b (the direction perpendicular to the horizontal direction X from which the flap base end 41c extends) coincides with (is parallel to) the left-right direction of the pouch (the direction from which the second imaginary line L2 extends). Furthermore, when the flap piece 41b is formed at a position that straddles the first virtual line L1, it is preferable to form an overlapping peripheral portion 42b at a position that straddles the first virtual line L1, and when the flap piece 41b is formed at a position that straddles the second virtual line L2, it is preferable to form an overlapping peripheral portion 42b at a position that straddles the second virtual line L2.

[0035] Next, the steam venting penetration 45, which serves as an auxiliary steam vent, will be described below.

[0036] First, in this embodiment, the steam venting penetrations 45 are formed in two locations, as shown in Figure 1, located off-center to the left and right sides of the pouch in the left-right direction.

[0037] As shown in Figure 1, each steam venting penetration 45 is composed of a notched slit that penetrates the branched film 31 in the film thickness direction (without removing any material). Each steam venting penetration 45 is formed along the upper end bending portion 32, which serves as a film bending portion 50, at least a part of it (the entire portion in the example shown in Figure 1), and functions as a film weakening portion 60.

[0038] The specific form of the film weakening portion 60 (steam venting penetration portion 45) is not limited to that shown in Figure 1. Any form is acceptable as long as at least a part of it overlaps the film bending portion 50 (upper end bending portion 32) and weakens the film strength at that location compared to the surrounding area. Modified examples of the film weakening portion 60 will be described below using Figures 6 and 7.

[0039] First, in the example shown in Figure 1, the film weakening portion 60 was described as being composed of a notched slit formed to penetrate in the film thickness direction. However, the specific form of the film weakening portion 60 is not limited to this. For example, the film weakening portion 60 may be formed as a slit that does not penetrate in the film thickness direction (a so-called half-cut slit) formed partway in the film thickness direction, or as a hole-like structure that penetrates (or does not penetrate) in the film thickness direction as shown in Figures 6(c) to (f), or as a portion that has been processed to weaken the film strength by means of making numerous scratches, pressing a blade, laser, file or grinding stone-like object against it, or performing cold working (a process that thins the inner material by heating it to below the Vicat softening temperature and then pressing a convex mold against it). Furthermore, film weakening portions 60 formed in different forms (notched slits, half-cut slits, through-holes, non-through-holes, etc.) may be formed on the same pouch 10. For example, in the example shown in Figure 1, in addition to the film weakening portion 60 formed as notched slits, film weakening portions formed in forms other than notched slits (for example, half-cut slits) may also be formed.

[0040] Furthermore, when the film weakening portion 60 is formed as a slit (either a through-slit shape penetrating in the film thickness direction or a non-through-slit shape not penetrating), the specific form of the film weakening portion 60 is not limited to the linearly formed form shown in Figure 1 and Figure 6(g). The film weakening portion 60 may also be formed in a curved shape as shown in Figures 6(a), (b), and (h), or a combination of curves and straight lines.

[0041] Furthermore, when the film weakening portion 60 is formed as a slit (either a through-slit or a non-through-slit), it is preferable to form both ends 61 of the slit on the film bending portion 50, as shown in Figures 1 and 6(a) and (b). In the example shown in Figure 1, the intermediate slit portion 62 connecting both ends 61 of the slit is formed in a straight line that extends along the film bend portion 50. In the examples shown in Figures 6(a), 6(b), and 6(h), the intermediate slit portion 62 is formed to connect both ends 61 of the slit without intersecting a virtual line that linearly connects both ends 61 of the slit, and to demarcate the movable piece (flap piece). In the examples shown in Figures 6(a) and 6(b), from the viewpoint of effectively stabilizing the film bending position by the film weakening portion 60, it is preferable to set the distance W3 between the ends 61 of the slit in the extending direction of the film bending portion 50 to be larger than the width H3 of the intermediate portion 62 of the slit in a direction perpendicular to the extending direction of the film bending portion 50 (the vertical width H3 of the widest part of the slit). The specific settings for widths W3 and H3 can be determined arbitrarily depending on the embodiment.

[0042] Furthermore, when forming the film weakening portion 60 in the shape of a hole (either a through-hole penetrating in the film thickness direction or a non-through-hole), it is preferable that at least a portion of its outer edge overlaps with a portion of the film bending portion 50, as shown in Figures 6(c) to (f). In the examples shown in Figures 6(c) to 6(f), from the viewpoint of effectively stabilizing the film bending position by the film weakening portion 60, it is preferable to set the width W4 of the portion of the outer edge of the film weakening portion 60 that overlaps with the film bending portion 50 in the extending direction of the film bending portion 50 to be larger than the width H4 of the film weakening portion 60 in the direction perpendicular to the extending direction of the film bending portion 50 (the vertical width H4 of the widest part of the film weakening portion 60). Furthermore, in the examples shown in Figures 6(c) to 6(f), it is preferable to set the width H4 of the film weakening portion 60 to a smaller size in order to effectively demonstrate the effect of stabilizing the film folding position by the film weakening portion 60. In other words, it is preferable to set the width H4 of the film weakening portion 60 to a smaller size than in the examples shown in Figures 6(e) and 6(f), compared to the examples shown in Figures 6(c) and 6(d). The specific settings for the widths W4 and H4 can be determined arbitrarily depending on the embodiment.

[0043] Furthermore, in the example shown in Figure 1 above, the film bending portion 50 where the film weakening portion 60 is formed was described as being the upper end bending portion 32 of the branched film 31. However, the specific location of the film bending portion 50 where the film weakening portion 60 is formed can be any location where the film is bent (or where a bending process has been applied to maintain the bent state), such as those shown in Figures 7(a) and 7(b). In the example shown in Figure 7(a), the connection point between the back-side film portion 42 and the front-side film 21 at the lower end 33 of the pouch branch portion 30 (the position that overlaps with the side seal portion 11b when the pouch is viewed from above) is the film bend portion 50 where the (slit-shaped) film weakening portion 60 is formed. In addition, the upper end bend portion 32 of the film bend portion 50 (the position that overlaps with the side seal portion 11b when the pouch is viewed from above) also has the (slit-shaped) film weakening portion 60 formed thereon. Furthermore, in the example shown in Figure 7(b), the folded portion of the bottom film that constitutes the bottom of the so-called standing pouch (the portion that overlaps with the side seal portion when the pouch is viewed from above, that is, the portion that overlaps with the side seal portion where the bottom film, the front film portion, and the back film are heat-sealed together) is the film bend portion 50 where the (slit-shaped) film weakening portion 60 is formed. Furthermore, as shown in the example in Figures 7(a) and 7(b), when the pouch is viewed from above as shown in Figures 7(a) and 7(b), if the film weakening portion 60 is formed at a position that overlaps with various heat-sealed sealing portions (for example, a sealing portion formed by heat-sealing a part of the film on which the film bend portion 50 is formed to another part of the film on which the film bend portion 50 is formed, to at least one of another film) such as the bag-making sealing portion 11 (side sealing portion 11b), and at a position where the film weakening portion 60 is isolated from the contents-containing portion 12 by the sealing portion, then there is no need to consider leakage of the contents from the contents-containing portion 12, and thus a degree of design freedom for the film weakening portion 60 can be ensured, such as by adopting a slit that penetrates in the film thickness direction as the film weakening portion 60.

[0044] Although embodiments of the present invention have been described in detail above, the present invention is not limited to the above embodiments, and various design changes can be made without departing from the scope of the present invention as described in the claims, such as constructing the pouch 10 by arbitrarily combining the configurations of the above or below embodiments or modified examples.

[0045] For example, the specific forms of each film 21, 22, 31 constituting the pouch 10 may be any known synthetic resin films such as polyester, polypropylene, polyamide, or coating films or vapor-deposited films that provide gas barrier properties or moisture barrier properties to these synthetic resin films, or any synthetic resin films formed by laminating paper or aluminum foil onto the synthetic resin film. Furthermore, each of the films 21, 22, and 31 constituting the pouch 10 may be formed as separate films, or at least some of the films may be formed as a single, continuous film. Furthermore, although the above-described embodiment was explained assuming that the contents of the pouch 10 are food, the specific form of the contents is not limited to food and can be anything that contains moisture.

[0046] Furthermore, in the embodiments described above, the slit 41a that demarcates the flap piece 41b was described as being formed as a notched slit (without material removal), but the specific form of the slit 41a is not limited to this, and it may be formed as a slit with width (a hole-like) (with material removal). Furthermore, in the above-described embodiment, the flap piece 41b was described as being formed in such an orientation that the free end 41d of the flap is closer to the planned communication start portion 43a of the steam vent seal portion 43 and the base end 41c of the flap is further away, as shown in Figure 2. However, the specific form of the flap piece 41b (slit 41a) is not limited to the above and can be any form. For example, the flap piece 41b (slit 41a) may be formed in such an orientation that the free end 41d of the flap is further away from the planned communication start portion 43a and the base end 41c of the flap is closer.

[0047] Furthermore, although the above-described embodiment was explained assuming that an overlapping peripheral portion 42b is formed on the branched back side film portion 42, it is not necessary to form such an overlapping peripheral portion 42b.

[0048] Furthermore, although the steam vent seal portion 43 is formed as being continuous with the bag-making seal portion 11 in the example shown in Figure 1, the steam vent seal portion 43 may also be formed independently of the bag-making seal portion 11.

[0049] Furthermore, in the embodiment described above, the steam release portion 44 is formed as an area where the branch front film portion 41 and the branch back film portion 42 are not heat-sealed (unsealed portion). However, the steam release portion 44 may also be formed as a weakly bonded portion where heat bonding is applied between the film portions 41 and 42 less strongly than the steam release seal portion 43 (or the bag-making seal portion 11), or as a patterned bonded portion where knurling seals or the like are applied to the film portions 41 and 42.

[0050] Furthermore, in the above-described embodiment, the flap piece 41b was formed on the front side film portion 41 of the branch and the steam vent hole 42a was formed on the back side film portion 42 of the branch. However, conversely, the flap piece 41b may be formed on the back side film portion 42 of the branch and the steam vent hole 42a may be formed on the front side film portion 41 of the branch.

[0051] Furthermore, although the above-described embodiment was explained assuming that a flap piece 41b and a steam vent hole 42a are provided as the main steam vent, it is also possible to design the system so that steam is discharged only from the steam vent penetration 45 formed on the upper end bent portion 32, without forming such a main steam vent. Furthermore, when a main steam vent is formed in addition to the steam vent penetration 45, the specific form of the main steam vent is not limited to the flap piece 41b and steam vent hole 42a as described above, but a slit or hole formed in at least one of the film portions 41 and 42 may be formed as the main steam vent.

[0052] Furthermore, in the embodiments described above, the film weakening portion 60 (steam venting penetration portion 45) was described as being formed in two locations, offset from the center in the left-right direction of the pouch. However, the specific number and formation location of the film weakening portion 60 (steam venting penetration portion 45) are not limited to this, and any such configuration is acceptable as long as at least a part of it is formed on the film bending portion 50 (upper end bending portion 32).

[0053] Furthermore, in the example shown in Figure 1 above, the planned communication start portion 43a was described as being formed to protrude toward the contents storage portion 14 side of the steam vent seal portion 43 (formed closest to the center of the contents storage portion 14) and being the part of the steam vent seal portion 43 that first begins to peel. However, the specific form of the planned communication start portion 43a may also be a part of the steam vent seal portion 43 that is designed to be the first to peel by methods such as varying the seal strength of each part of the steam vent seal portion 43.

[0054] Furthermore, in the above-described embodiment, the steam venting mechanism 40 is configured such that, when heated in a microwave oven, the steam generated in the contents storage section 12 separates the heat-sealed films 41 and 42 at the steam venting seal section 43 (specifically the planned communication start section 43a), thereby connecting the contents storage section 12 and the steam release section 44, and releasing the steam in the contents storage section 12 to the outside through the steam release section 44. However, the specific structure for connecting the contents storage section 12 and the steam release section 44 during microwave heating (specific form of the planned communication start section 43a) is not limited to one that separates the heat-sealed films 41 and 42 in the steam release seal section 43 as described above, but any structure that uses the steam generated in the contents storage section 12 to connect the contents storage section 12 and the steam release section 44 is acceptable. For example, as shown in Figure 8, in the steam vent seal section 43, a weakened section may be formed on at least one of the films 41 and 42 that is peeled off or destroyed by steam generated in the contents storage section 12, and this weakened section may be used as a planned communication start section 43a, so that when heated in a microwave oven, the weakened section (planned communication start section 43a) is peeled off or destroyed, forming a steam passage P in at least one of the films 41 and 42 that connects the contents storage section 12 and the steam release section 44. As the weakened section for forming such a steam passage P, it is conceivable to use the interlayers where the adhesive strength is set to be weak when the films 41 and 42 are formed as a laminated film, or a weakened section that is mechanically weak and easily destroyed. [Explanation of Symbols]

[0055] 10... Pouch 11 ··· Seal section for bag making 11a ··· Top seal section 11b ··· Side seal section 12 ··· Contents storage compartment 20... Pouch body 21 ··· Front film 21a ··· Film fold top 22 ··· Backside film 30... Pouch branching section 31... Branching film 32... Upper end side bending part 33... Lower end of pouch branch 40... Steam venting mechanism 41... Branch front side film section 41a ··· Slit 41b ··· Flap piece 41c ··· Flap base 41d ··· Flap free end 42... Film section on the back of the branch 42a ··· Steam vent hole 42b... Overlapping peripheral area 43... Steam vent seal section 43a ··· Section where communication is scheduled to begin 44... Steam release section 50 ··· Film bend section 60 ··· Film weakening area 61... Slit ends 62... Slit middle section L1 ··· First virtual line L2 ··· Second virtual line X ··· Lateral Y ··· Vertical direction

Claims

1. A pouch having a folded film section where the film is folded, The aforementioned film has a film weakening portion formed therein. The aforementioned film weakening portion is formed, at least a part of it, on the film bending portion. The pouch comprises a pouch body having a content storage section and a pouch branch section formed protruding outward from the outer film constituting the pouch body, and is a microwave-safe pouch equipped with a steam release mechanism that releases steam from the content storage section to the outside through a steam release section formed in the pouch branch section when heated. The aforementioned pouch branch portion consists of a branch film that is folded at its upper end bend, The lower ends of the branching films are connected to the front films, respectively. The branched film has a vapor venting penetration formed that penetrates through the film in the direction of its thickness. The aforementioned steam venting penetration is formed on the upper end bent portion which is the film bent portion, and functions as the film weakening portion. The steam release mechanism has a communication start section that connects the contents storage section and the steam release section during heating. The steam venting mechanism has a main steam vent formed at a position closer to the planned communication start portion than the steam venting penetration portion, The aforementioned steam venting penetration is formed as an auxiliary steam vent, The branch film has a branch back film portion arranged opposite to the front film, and a branch front film portion arranged on the front side of the branch back film portion. The steam venting mechanism has, as the main steam vent, a flap piece partitioned by a slit formed in one of the branch front film portion or the branch back film portion at the steam opening, and a steam venting hole formed in the other of the branch front film portion or the branch back film portion at the steam opening, such that at least a part of the flap piece overlaps the flap piece in the front-back direction. The pouch is characterized in that the branched film has an overlapping peripheral portion that is arranged to overlap a part of the flap piece in the front-back direction at the peripheral edge of the steam vent hole.

2. A pouch having a folded film section where the film is folded, The aforementioned film has a film weakening portion formed therein. The aforementioned film weakening portion is formed, at least a part of it, on the film bending portion. The pouch comprises a pouch body having a content storage section and a pouch branch section formed protruding outward from the outer film constituting the pouch body, and is a microwave-safe pouch equipped with a steam release mechanism that releases steam from the content storage section to the outside through a steam release section formed in the pouch branch section when heated. The aforementioned pouch branch portion consists of a branch film that is folded at its upper end bend, The lower ends of the branching films are connected to the front films, respectively. The branched film has a vapor venting penetration formed that penetrates through the film in the direction of its thickness. The aforementioned steam venting penetration is formed on the upper end bent portion which is the film bent portion, and functions as the film weakening portion. The steam release mechanism has a communication start section that connects the contents storage section and the steam release section during heating. The steam venting mechanism has a main steam vent formed at a position closer to the planned communication start portion than the steam venting penetration portion, The aforementioned steam venting penetration is formed as an auxiliary steam vent, The branch film has a branch back film portion arranged opposite to the front film, and a branch front film portion arranged on the front side of the branch back film portion. The steam venting mechanism is characterized in that the pouch has, as the main steam vent, a flap piece partitioned by a slit formed in the branch front side film portion at the steam opening portion, and a steam vent hole formed in the branch back side film portion at the steam opening portion such that at least a part of the flap piece overlaps the flap piece in the front-back direction.

3. The aforementioned film weakening portion is composed of a slit having an intermediate portion connecting both ends of the slit, The pouch according to claim 1 or 2, characterized in that both ends of the slit are formed on the folded portion of the film.

4. The pouch according to claim 3, characterized in that the intermediate portion of the slit is formed in a straight line, and the entire portion is formed along the folded portion of the film.

5. The pouch according to claim 3, characterized in that the intermediate portion of the slit is formed so as to connect the two ends of the slit in a way that divides the movable piece, without intersecting a virtual line that linearly connects the two ends of the slit.

6. The pouch according to claim 5, characterized in that the distance between the two ends of the slit in the extending direction of the film fold is set to be greater than the width of the middle portion of the slit in a direction perpendicular to the extending direction of the film fold.

7. The aforementioned film weakening portion is formed in the shape of a hole, The pouch according to claim 1 or 2, characterized in that the film weakening portion is formed such that at least a portion of its outer edge overlaps a portion of the film bending portion.

8. The pouch according to claim 7, characterized in that the width of the portion of the outer edge of the film weakening portion that overlaps with the film bending portion in the extending direction of the film bending portion is set to be greater than the width of the film weakening portion in a direction perpendicular to the extending direction of the film bending portion.

9. The pouch has a sealed portion formed by heat-sealing the film, The pouch according to claim 1 or 2, characterized in that the film weakening portion is formed in a position that overlaps with the sealing portion when the pouch is viewed from above, and in a position where the film weakening portion is isolated from the contents storage portion by the sealing portion.

Images