Microwave pouch
The microwave pouch design with a steam release mechanism using overlapping films and guided flap pieces addresses the issue of steam venting efficiency and leakage, ensuring proper steam release and containment of contents.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- TOYO SEIKAN KAISHA LTD
- Filing Date
- 2022-03-18
- Publication Date
- 2026-05-15
AI Technical Summary
Microwave pouches with steam venting mechanisms face issues where increasing the steam vent hole size leads to content leakage, while reducing the size or using slits may result in insufficient steam release and pouch expansion, causing thermal damage.
A microwave pouch design with a steam release mechanism comprising overlapping films, a flap piece partitioned by a slit, and a steam release hole, where the flap piece is positioned to overlap in the front-back direction, and the steam vent hole is narrower in the lateral direction, guided by film folds to ensure efficient steam release without leakage.
The design achieves both effective steam release and prevents content leakage by ensuring the flap piece opens properly during heating, guided by film folds and overlapping peripheral portions, containing any leaked content within the pouch.
Smart Images
Figure 0007859105000001 
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Figure 0007859105000003
Abstract
Description
Technical Field
[0001] The present invention relates to a pouch for a microwave oven, which has a steam venting mechanism for automatically venting internal steam during heating.
Background Art
[0002] Conventionally, packaged foods that contain cooked or semi-cooked foods in a pouch formed into a bag shape by thermally bonding overlapping films and are heated and cooked by a microwave oven when the food is eaten have been on the market.
[0003] In such a pouch for a microwave oven, when heated in a microwave oven, the internal pressure of the pouch increases due to steam generated from the food and thermal expansion of the internal air, and there is a risk that the pouch may burst or deform, or the food inside the pouch may scatter due to bursting.
[0004] Therefore, in recent years, it is generally known that a steam venting mechanism for automatically venting internal steam during heating is provided in a pouch for a microwave oven (for example, see Patent Document 1). As one aspect of such a steam venting mechanism, there is known a steam venting seal portion formed by thermally welding overlapping films and isolating the steam release portion from the content accommodating portion, and a steam venting hole formed through one of the two films disposed in the steam release portion.
[0005] In the pouch for a microwave oven disclosed in this Patent Document 1, when the pressure in the content accommodating portion increases with heating by a microwave oven, a part of the steam venting seal portion peels off, and the content accommodating portion and the steam release portion communicate with each other, and the steam in the content accommodating portion is discharged to the outside through the steam venting hole.
Prior Art Documents
Patent Documents
[0006]
Patent Document 1
Summary of the Invention
[0007] However, with microwave pouches equipped with such a steam venting mechanism, increasing the size of the steam vent hole ensures sufficient steam release during heating, but depending on the heating conditions, the contents may leak out of the steam vent hole along with the steam. On the other hand, if the steam vent hole is made smaller, or if a slit is formed instead of a steam vent hole, depending on the degree of expansion of the pouch during heating, sufficient steam release may not be ensured, and the pouch may remain expanded due to steam for a long time, causing thermal damage to the inner material of the pouch.
[0008] Therefore, the present invention aims to solve these problems and provide a microwave pouch with a simple structure that achieves both good steam release and suppression of contents leakage. [Means for solving the problem]
[0009] The present invention relates to a microwave pouch equipped with a steam release section isolated from the contents storage section by a steam release seal section, and a steam release mechanism that releases steam from the contents storage section to the outside through the steam release section when heated, wherein the steam release mechanism comprises a first film and a second film arranged in overlapping order, the steam release seal section formed by heat welding the first film and the second film, a flap piece partitioned by a slit formed in the first film at the steam release section, and a steam release hole formed in the second film at the steam release section such that at least a portion of the flap piece overlaps the flap piece in the front-back direction. Furthermore, the second film has an overlapping peripheral portion at the periphery of the steam vent hole, which is arranged to overlap a part of the flap piece in the front-back direction. This solves the aforementioned problem. Furthermore, the present invention provides a microwave pouch equipped with a steam release section isolated from the contents storage section by a steam release seal section, and a steam release mechanism that releases steam from the contents storage section to the outside through the steam release section when heated, wherein the steam release mechanism comprises a first film and a second film arranged in overlapping order, a steam release seal section formed by heat welding the first film and the second film, a flap piece partitioned by a slit formed in the first film at the steam release section, and a steam release hole formed in the second film at the steam release section such that at least a part of the flap piece overlaps the flap piece in the front-back direction, wherein the steam release seal section has a planned communication start section that connects the contents storage section and the steam release section when heated, and the flap piece has a portion formed closer to the planned communication start section than the portion of the steam release hole closest to the planned communication start section, thereby solving the above problem. Furthermore, the present invention provides a microwave pouch equipped with a steam release section isolated from the contents storage section by a steam release seal section, and a steam release mechanism that releases steam from the contents storage section to the outside through the steam release section when heated, wherein the steam release mechanism comprises a first film and a second film arranged in overlapping order, the steam release seal section formed by heat welding the first film and the second film, a flap piece partitioned by a slit formed in the first film at the steam release section, and the first film being positioned such that at least a part of the first film overlaps the flap piece in the front-back direction. The microwave pouch has a steam vent hole formed in the second film at the steam release section, and comprises a pouch body having the contents storage section, and a pouch branch section formed protruding outwards from the outer film constituting the pouch body, the steam release mechanism is formed in the pouch branch section, the pouch branch section is provided such that the second film having the steam vent hole faces the outer film of the pouch body, and the upper end of the pouch branch section is connected to the first film and the second film, thereby solving the above problem. Furthermore, the present invention provides a microwave pouch equipped with a steam release section isolated from the contents storage section by a steam release seal section, and a steam release mechanism that releases steam from the contents storage section to the outside through the steam release section when heated, wherein the steam release mechanism comprises a first film and a second film arranged in overlapping order, a steam release seal section formed by heat welding the first film and the second film, a flap piece partitioned by a slit formed in the first film at the steam release section, and a steam release hole formed in the second film at the steam release section such that at least a part of the flap piece overlaps the flap piece in the front-back direction, and the microwave pouch is The invention solves the aforementioned problem by comprising a pouch body having the contents storage section and a pouch branch section formed protruding outward from the outer film constituting the pouch body, the steam venting mechanism being formed in the pouch branch section, the pouch branch section being provided such that the second film having the steam venting hole faces the outer film of the pouch body, the flap piece having a flap base end extending along the transverse direction and connected to the first film, and a flap free end moving in the longitudinal direction perpendicular to the transverse direction away from the flap base end, and the steam venting hole being formed such that its width in the transverse direction is narrower than its width in the longitudinal direction. Furthermore, the present invention provides a microwave pouch equipped with a steam release section separated from the contents storage section by a steam release seal section, and a steam release mechanism that releases steam from the contents storage section to the outside through the steam release section when heated, wherein the steam release mechanism comprises a first film and a second film arranged in overlapping order, the steam release seal section formed by heat welding the first film and the second film, a flap piece partitioned by a slit formed in the first film at the steam release section, and a steam release hole formed in the second film at the steam release section such that at least a part of the flap piece overlaps the flap piece in the front-back direction, and the microwave pouch is equipped with a steam release mechanism that releases steam from the contents storage section The invention solves the aforementioned problem by comprising a pouch body having a pouch branch portion formed to protrude outward from the front film constituting the pouch body, the steam venting mechanism being formed in the pouch branch portion, the pouch branch portion being provided such that the second film having the steam venting hole faces the front film of the pouch body, the flap piece having a flap base end extending along the transverse direction and connected to the first film, and a flap free end moving in the longitudinal direction perpendicular to the transverse direction away from the flap base end, and when viewed in the longitudinal direction, the range of formation of the steam venting hole in the transverse direction being set to fall within the range of formation of the flap piece in the transverse direction. Furthermore, the present invention provides a microwave pouch equipped with a steam release section separated from the contents storage section by a steam release seal section, and a steam release mechanism that releases steam from the contents storage section to the outside through the steam release section when heated, wherein the steam release mechanism comprises a first film and a second film arranged in overlapping order, the steam release seal section formed by heat welding the first film and the second film, a flap piece partitioned by a slit formed in the first film at the steam release section, and a steam release hole formed in the second film at the steam release section such that at least a part of the flap piece overlaps the flap piece in the front-back direction, and the microwave pouch comprises a pouch body having the contents storage section and the pouch body comprising The pouch comprises a front film and a pouch branch formed protruding outwards from the front film, the steam venting mechanism is formed in the pouch branch, the pouch branch is provided such that the second film having the steam vent hole faces the front film of the pouch body, the flap piece has a flap base end extending along the transverse direction and connected to the first film, and a flap free end in the longitudinal direction perpendicular to the transverse direction and away from the flap base end, the second film has an overlapping peripheral portion at the periphery of the steam vent hole that overlaps a part of the flap piece in the front-back direction, and when viewed in the longitudinal direction, the overlapping peripheral portion has a portion located within the range of the steam vent hole formation in the transverse direction, thereby solving the above problem. [Effects of the Invention]
[0010] According to the invention of claim 1, by forming a steam vent hole in the second film and a slit that partitions the flap piece in the first film, it is possible to achieve both efficient steam release and suppression of leakage of contents. Furthermore, according to the invention of claim 1, the second 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 prevents the flap piece from moving toward the second film side, thereby preventing the flap piece 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.
[0011] Claims 2 and 3 According to the invention, the overlapping peripheral portion is formed to overlap in the front-to-back direction with respect to at least a portion of the part of the free end of the flap that is furthest from the base end of the flap in the longitudinal direction, thereby effectively preventing the entire flap piece from moving toward the second film side. Claim 4 According to the invention, since the flap piece has a portion formed closer to the planned communication start point than the portion of the steam vent hole closest to the planned communication start point, it is possible to open a portion of the flap piece before steam begins to be released from the steam vent hole during heating. This ensures that the flap piece is opened and prevents steam from being released only from the steam vent hole. Claim 5 According to the invention, by positioning the second film having a steam vent hole opposite the front film of the pouch body, 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. Furthermore, by positioning the second film with a steam vent hole on the back side of the first film on which the flap piece is formed, it is possible to guide the film fold peak, which is formed on the front film of the pouch body as a convex shape facing outwards due to the expansion of the pouch body during heating, to form on the back side 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. Claim 6According to the invention, the flap piece has a flap base end connected to the first film and a flap free end separated longitudinally from the flap base end, and the steam vent hole is formed such that its width in the lateral direction is narrower than its width in the vertical direction. This makes it possible to guide the film fold apex to extend along the vertical direction near the flap piece and the steam vent hole, thereby effectively pushing up the flap piece and making it easier for the flap piece to open when heated. Claims 7 and 8 According to the invention, when viewed in the vertical direction, the range of steam venting holes in the horizontal direction is set to fall within the range of flap pieces in the horizontal direction. This allows the flap pieces to be pushed up by the vertically extending folds of the film, making it easier for the flap pieces to open during heating. Claim 9 According to the invention, when viewed in the vertical direction, the overlapping peripheral portion has a part located within the range of steam vent hole formation in the horizontal direction. By utilizing the formation of the above-mentioned film fold apex, the overlapping peripheral portion, which is arranged to overlap a part of the flap piece in the front-back direction, can also push up the flap piece from the back side, making it easier for the flap piece to open when heated. Claim 10 According to the invention, by forming a flap piece and a steam vent hole in a position where a film fold is easily formed due to the expansion of the pouch body during heating, the above-mentioned film fold is more easily formed on the back side of the flap piece. [Brief explanation of the drawing]
[0012] [Figure 1] An explanatory diagram showing a microwave pouch according to one embodiment of the present invention. [Figure 2] An explanatory diagram focusing on the steam venting mechanism. [Figure 3] An explanatory diagram illustrating the relationship between the flap piece and the steam vent hole. [Figure 4] An explanatory diagram illustrating the fold at the top of the film. [Figure 5] Explanatory drawing showing a modified example of the steam venting mechanism. [Figure 6] Explanatory drawing showing a modified example of the pouch for a microwave oven. [Figure 7] Explanatory drawing showing a modified example of the steam venting mechanism.
Mode for Carrying Out the Invention
[0013] Hereinafter, the pouch 10 for a microwave oven according to an embodiment of the present invention will be described based on the drawings.
[0014] First, as shown in FIG. 1, the pouch 10 for a microwave oven is formed into a bag shape by forming a bag-making seal portion 11 obtained by thermally bonding a resin film at a predetermined location, and food and other contents are stored in the inner content storage portion 12.
[0015] As shown in FIG. 1, the pouch 10 for a microwave oven in this embodiment is configured as a so-called branched pouch including a pouch main body 20 having a content storage portion 12 and a pouch branch portion 30 formed to protrude from the front side film 21 constituting the pouch main body 20.
[0016] As shown in FIG. 1, the pouch main body 20 has a front side film 21 and a back side film 22 that are stacked in the front-back direction, and is configured in a bag shape by forming bag-making seal portions 11 (top seal portion 11a, side seal portion 11b) obtained by thermally welding predetermined locations of these films 21 and 22 to each other.
[0017] As shown in FIG. 1, the pouch branch portion 30 is configured as a portion formed to protrude from the front side film 21 of the pouch main body 20 over the entire area in the left-right direction of the pouch in the middle of the up-down direction of the pouch. As shown in FIG. 1, the pouch branch portion 30 is a portion formed to protrude from the front side film 21 of the pouch main body 20, and has a second film 42 arranged to face the front side film 21 of the pouch main body 20 and a first film 41 arranged on the front side of the second film 42.
[0018] As shown in Figure 1, at the upper end portion 31 of the pouch branching portion 30, the films 41 and 42 are connected (in this embodiment, they are formed continuously and integrally with each other). Alternatively, the films 41 and 42 may be formed separately and heat-sealed together at the upper end portion 31 of the pouch branching portion 30. Furthermore, as shown in Figure 1, films 41 and 42 are connected on both the left and right sides of the pouch branch portion 30, and in this embodiment, films 41 and 42 are heat-sealed at the side seal portion 11b. Furthermore, as shown in Figure 1, the films 41 and 42 are not connected at the lower end portion 32 of the pouch branching section 30. Furthermore, at the lower end portion 32 of the pouch branch portion 30, as shown in Figure 1, films 21 and 41 are connected (in this embodiment, they are formed continuously and integrally with each other), and films 21 and 42 are connected (in this embodiment, they are formed continuously and integrally with each other). Note that at the lower end portion 32 of the pouch branch portion 30, separately formed films 21 and 41 may be heat-sealed, or separately formed films 21 and 42 may be heat-sealed. Furthermore, a fold is formed (folded) at the connection point between the second film 42 and the front film 21 at the lower end 32 of the pouch branch section 30. As a result, when the pouch branch section 30 is unloaded (no force is being applied), the second film 42 remains facing the front film 21, as shown in Figure 1. Furthermore, a fold is formed at the connection point between films 41 and 42 at the upper end 31 of the pouch branching section 30, while no fold is formed at the connection point between the first film 41 and the front film 21 at the lower end 32 of the pouch branching section 30.
[0019] The microwave pouch 10 is 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. In this embodiment, as shown in Figure 1, the steam release mechanism 40 is formed in the pouch branch section 30.
[0020] As shown in Figure 1, the steam venting mechanism 40 includes a first film 41 and a second film 42 arranged in overlapping positions, a steam venting seal portion 43 formed by heat welding the first film 41 and the second film 42, a steam opening 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 first film 41 at the steam opening portion 44, and a steam venting hole 42a formed in the second film 42 at the steam opening portion 44 such that at least a part of the second film 42 overlaps the flap piece 41b in the front-back 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 peels off the steam venting seal section 43, 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 of the pouch through the steam venting holes 42a and slits 41a formed in the steam release section 44.
[0022] The following describes each component of the steam venting mechanism 40.
[0023] First, as shown in Figures 1 and 2, the flap piece 41b formed on the first film 41 is partially separated from the peripheral portion of the first film 41 at the steam release section 44 by a U-shaped slit 41a, 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 transverse direction X, and is connected to the first film 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 longitudinal direction Y which is perpendicular to the transverse 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.
[0024] Furthermore, as shown in Figure 2, the second film 42 has a vapor vent hole 42a that penetrates the second film 42 in the front-to-back direction. As shown in Figure 2, the second film 42 has an overlapping peripheral portion 42b that is positioned to overlap a part of the flap piece 41b in the front-back direction, so as to prevent the flap piece 41b from moving toward the second film 42 side (back side) at the periphery of the steam vent hole 42a.
[0025] 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.
[0026] 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.
[0027] 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 second film 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.
[0028] Furthermore, in the example shown in Figure 1, a second film 42 is placed between the front film 21 of the pouch body 20 and the first film 41 on which the flap piece 41b is formed, and the second film 42 has a steam vent hole 42a formed such that at least a portion 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 second film 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.
[0029] 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 21a and the fold that occurs in the second film 42 due to the formation of the film fold 21a.
[0030] 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.
[0031] 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.
[0032] 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.
[0033] Furthermore, the formation positions of the flap piece 41b and the steam vent hole 42a in the planar direction of the microwave 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.
[0034] 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 present invention as described in the claims, such as constructing a microwave pouch 10 by arbitrarily combining the configurations of the above or below embodiments or modified examples.
[0035] For example, the specific forms of each film 21, 22, 41, 42 constituting the microwave pouch 10 may be any known synthetic resin film such as polyester, polypropylene, or polyamide, or a known synthetic resin film such as a coating film or vapor-deposited film that provides gas barrier properties or moisture barrier properties to such a synthetic resin film, or a synthetic resin film that is formed by laminating paper or aluminum foil onto the synthetic resin film. Furthermore, the films 21, 22, 41, and 42 that make up the microwave 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 microwave pouch 10 are food, the specific form of the contents is not limited to food and can be anything that contains moisture.
[0036] Furthermore, although the above-described embodiment explained that the steam venting mechanism 40 is formed in the pouch branching portion 30 of the branched pouch, the position of the steam venting mechanism 40 is not limited to the above, and can be any location where the second film 42 and the first film 41 are arranged in overlapping positions. In the example shown in Figure 6, which is an example of a modified version, the microwave pouch 10 is configured as a standing pouch, and the steam release mechanism 40 has a first film 41 and a second film 42 as films constituting the pouch body 20, a steam release seal portion 43 formed by heat welding the films 41 and 42, a flap piece 41b partitioned by a slit 41a formed in the first film 41 in the steam release portion 44 which is isolated from the contents storage portion 12 by the steam release seal portion 43, and a steam release hole 42a formed in the second film 42 in the steam release portion 44.
[0037] Furthermore, although the examples shown in Figures 1 and 6 describe the microwave pouch 10 as being configured as a branched pouch or a standing pouch, the specific form of the microwave pouch 10 can be anything, such as a so-called flat pouch, as long as it is equipped with a first film 41 and a second film 42 arranged in a stacked manner.
[0038] 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.
[0039] Furthermore, although the above-described embodiment was explained assuming that the second film 42 has an overlapping peripheral portion 42b, it is not necessary to form such an overlapping peripheral portion 42b.
[0040] Furthermore, while the steam vent seal portion 43 is formed as being continuous with the bag-making seal portion 11 in the examples shown in Figures 1 and 6, the steam vent seal portion 43 may also be formed independently of the bag-making seal portion 11.
[0041] Furthermore, in the example shown in Figure 1 above, the planned communication start portion 43a is formed as a part of the steam vent seal portion 43 that protrudes toward the contents storage portion 14 (the part closest to the center of the contents storage portion 14), and in the example shown in Figure 6 above, it is described as being formed as the part closest to the center of the contents storage portion 14. However, the specific form of the planned communication start portion 43a is not limited to the above; it can be any part of the steam vent seal portion 43 that is designed to begin peeling first, such as a part whose position is determined by varying the seal strength of each part of the steam vent seal portion 43.
[0042] Furthermore, in the above-described embodiment, the steam release portion 44 is formed as an area where the first film 41 and the second film 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 films 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 films 41 and 42.
[0043] 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 7, in the steam vent seal section 43, a weakened portion may be formed in at least one of the first film 41 or the second film 42 that is peeled off or destroyed by steam generated in the contents storage section 12. This weakened portion may be used as a planned communication start portion 43a, so that when heated in a microwave oven, the weakened portion (planned communication start portion 43a) is peeled off or destroyed, forming a steam passage P in at least one of the first film 41 or the second film 42 that connects the contents storage section 12 and the steam release section 44. As the weakened portion for forming such a steam passage P, it is conceivable to use the interlayers where the adhesive force is set to be weak when the films 41 and 42 are formed as a laminated film, or a weakened portion that is mechanically weak and easily destroyed. [Explanation of Symbols]
[0044] 10... Microwave 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... Upper end of pouch branch 32... Lower end of pouch branch 40... Steam venting mechanism 41 ··· Film 1 41a ··· Slit 41b ··· Flap piece 41c ··· Flap base 41d ··· Flap free end 42 ··· Second film 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 L1 ··· First virtual line L2 ··· Second virtual line X ··· Lateral Y ··· Vertical direction
Claims
1. A microwave pouch equipped with a steam release section isolated from the contents storage section by a steam release seal section, and a steam release mechanism that releases steam from the contents storage section to the outside through the steam release section during heating, The steam venting mechanism comprises a first film and a second film arranged in a stacked manner, a steam venting seal portion formed by heat welding the first film and the second film, a flap piece partitioned by a slit formed in the first film at the steam opening portion, and a steam venting hole formed in the second film at the steam opening portion such that at least a part of the second film overlaps the flap piece in the front-back direction. The microwave pouch is characterized in that the second 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. The flap piece has a flap base end that extends along the transverse direction and is connected to the first film, and a flap free end that is in the longitudinal direction perpendicular to the transverse direction and is away from the flap base end. The microwave pouch according to claim 1, characterized in that the overlapping peripheral portion is formed to overlap in the front-to-back direction with respect to at least a portion of the free end of the flap that is furthest from the base end of the flap in the vertical direction.
3. The steam vent seal section has a communication start section that connects the contents storage section and the steam release section when heated, The microwave pouch according to claim 2, characterized in that the flap piece is formed such that the free end of the flap is close to the planned communication start portion and the base end of the flap is farther away.
4. A microwave pouch comprising a steam release section isolated from the contents storage section by a steam release seal section, and a steam release mechanism for releasing steam from the contents storage section to the outside through the steam release section when heated, The steam venting mechanism comprises a first film and a second film arranged in a stacked manner, a steam venting seal portion formed by heat welding the first film and the second film, a flap piece partitioned by a slit formed in the first film at the steam opening portion, and a steam venting hole formed in the second film at the steam opening portion such that at least a part of the second film overlaps the flap piece in the front-back direction. The steam vent seal section has a communication start section that connects the contents storage section and the steam release section when heated, A microwave pouch characterized in that the flap piece has a portion formed closer to the planned communication start point than the portion of the steam vent hole closest to the planned communication start point.
5. A microwave pouch comprising a steam release section isolated from the contents storage section by a steam release seal section, and a steam release mechanism for releasing steam from the contents storage section to the outside through the steam release section when heated, The steam venting mechanism comprises a first film and a second film arranged in a stacked manner, a steam venting seal portion formed by heat welding the first film and the second film, a flap piece partitioned by a slit formed in the first film at the steam opening portion, and a steam venting hole formed in the second film at the steam opening portion such that at least a part of the second film overlaps the flap piece in the front-back direction. The microwave pouch comprises a pouch body having the contents storage section and a pouch branch section formed protruding outward from the outer film constituting the pouch body. The steam venting mechanism is formed in the pouch branch section, The pouch branch portion is provided such that the second film having the steam vent hole faces the front film of the pouch body. A microwave-safe pouch characterized in that the upper end of the pouch branching portion is connected to the first film and the second film.
6. A microwave pouch comprising a steam release section isolated from the contents storage section by a steam release seal section, and a steam release mechanism for releasing steam from the contents storage section to the outside through the steam release section when heated, The steam venting mechanism comprises a first film and a second film arranged in a stacked manner, a steam venting seal portion formed by heat welding the first film and the second film, a flap piece partitioned by a slit formed in the first film at the steam opening portion, and a steam venting hole formed in the second film at the steam opening portion such that at least a part of the second film overlaps the flap piece in the front-back direction. The microwave pouch comprises a pouch body having the contents storage section and a pouch branch section formed protruding outward from the outer film constituting the pouch body. The steam venting mechanism is formed in the pouch branch section, The pouch branch portion is provided such that the second film having the steam vent hole faces the front film of the pouch body. The flap piece has a flap base end that extends along the transverse direction and is connected to the first film, and a flap free end that is in the longitudinal direction perpendicular to the transverse direction and is away from the flap base end. A microwave pouch characterized in that the steam vent hole is formed such that its width in the horizontal direction is narrower than its height in the vertical direction.
7. A microwave pouch comprising a steam release section isolated from the contents storage section by a steam release seal section, and a steam release mechanism for releasing steam from the contents storage section to the outside through the steam release section when heated, The steam venting mechanism comprises a first film and a second film arranged in a stacked manner, a steam venting seal portion formed by heat welding the first film and the second film, a flap piece partitioned by a slit formed in the first film at the steam opening portion, and a steam venting hole formed in the second film at the steam opening portion such that at least a part of the second film overlaps the flap piece in the front-back direction. The microwave pouch comprises a pouch body having the contents storage section and a pouch branch section formed protruding outward from the outer film constituting the pouch body. The steam venting mechanism is formed in the pouch branch section, The pouch branch portion is provided such that the second film having the steam vent hole faces the front film of the pouch body. The flap piece has a flap base end that extends along the transverse direction and is connected to the first film, and a flap free end that is in the longitudinal direction perpendicular to the transverse direction and is away from the flap base end. A microwave pouch characterized in that, when viewed in the vertical direction, the range for forming the steam vent hole in the horizontal direction is set to fall within the range for forming the flap piece in the horizontal direction.
8. The microwave pouch according to claim 7, characterized in that the width of the flap piece in the lateral direction is set to be wider than the width of the steam vent hole in the lateral direction.
9. A microwave pouch comprising a steam release section isolated from the contents storage section by a steam release seal section, and a steam release mechanism for releasing steam from the contents storage section to the outside through the steam release section when heated, The steam venting mechanism comprises a first film and a second film arranged in a stacked manner, a steam venting seal portion formed by heat welding the first film and the second film, a flap piece partitioned by a slit formed in the first film at the steam opening portion, and a steam venting hole formed in the second film at the steam opening portion such that at least a part of the second film overlaps the flap piece in the front-back direction. The microwave pouch comprises a pouch body having the contents storage section and a pouch branch section formed protruding outward from the outer film constituting the pouch body. The steam venting mechanism is formed in the pouch branch section, The pouch branch portion is provided such that the second film having the steam vent hole faces the front film of the pouch body. The flap piece has a flap base end that extends along the transverse direction and is connected to the first film, and a flap free end that is in the longitudinal direction perpendicular to the transverse direction and is away from the flap base end. The second film has an overlapping peripheral portion at the periphery of the steam vent hole, which is arranged to overlap a part of the flap piece in the front-back direction. A microwave pouch characterized in that, when viewed in the vertical direction, the overlapping peripheral portion has a portion located within the range of steam vent hole formation in the horizontal direction.
10. The microwave pouch according to any one of claims 5 to 9, characterized in that the flap piece and the steam vent hole are formed at a position on the upper or lower side of the pouch body in the vertical direction of the pouch, straddling a first imaginary line that passes through the center of the pouch body in the left-right direction of the pouch body and extends along the vertical direction of the pouch, or at a position on the left or right side of the pouch body in the left-right direction of the pouch body, straddling a second imaginary line that passes through the center of the pouch body in the vertical direction of the pouch body and extends along the left-right direction of the pouch.