Steam release pouch

Abstract

To provide a steam release pouch that improves opening property by improving bottom opening property and makes it easier to eat a food as it is from the steam release pouch after opening after heat treatment.SOLUTION: A steam release pouch of the present invention includes a first sheet and a second sheet facing each other, and a bottom sheet between the first sheet and the second sheet, and includes a steam release part, the length in a width direction from the lower end of the inner edge of the part where the facing surfaces of the bottom sheet are joined to the virtual vertical line (A1) with respect to the outer edge of a bottom intermediate seal part including the intersection of the inner edge of the bottom side seal and the inner edge of the bottom intermediate seal and the length in the width direction from the lower end of the inner edge of the part where the facing surfaces of the bottom sheet are joined to the virtual vertical line (A2) with respect to the outer edge of a bottom intermediate seal part including the intersection of the inner edge of the bottom side seal and the inner edge of the bottom intermediate seal are equal, the ratio of the length of A1 to the length (B) of the inner edge of the bottom intermediate seal part in the width direction and the length of A2 is 1: 1: 1 to 1: 3: 1.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a steam release pouch for use in heating food or the like in a microwave oven or the like. [Background technology]

[0002] 2. Description of the Related Art Conventionally, as a steam release pouch used for heating food or the like in a microwave oven or the like, a steam release pouch having two opposing films and a bottom film and having a steam release portion on one side has been known. For example, Patent Document 1 describes a steam release pouch that has two opposing films and a bottom film interposed between the two films, and has an opening means provided below a steam release section provided in a side seal section. This steam release pouch makes it possible to reduce the distance between the opening position and the contents, making it easier to remove the contents. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2018-127257 A Summary of the Invention [Problem to be solved by the invention]

[0004] The steam release pouch described in Patent Document 1 has a problem in that when the pouch is opened after being heated in a microwave oven or the like and then the food contents are eaten directly from the pouch, the pouch has poor bottom opening properties and poor opening ability, making it difficult to eat the food. Therefore, an object of the present invention is to provide a steam release pouch which has improved opening properties by improving the bottom opening property of the steam release pouch, thereby making it easy to eat the food contents directly from the steam release pouch after opening the pouch following heating treatment in a microwave oven or the like. [Means for solving the problem]

[0005] The invention described in claim 1 is A steam release pouch comprising a first sheet and a second sheet facing each other, and a bottom sheet interposed between the first sheet and the second sheet by folding in a V-shape in a side view, the steam release pouch having a steam release section for releasing steam generated from contents, etc. The left and right side seal portions, the first bottom seal portion, and the second bottom seal portion are formed. The left and right side seal portions are substantially linear and include a portion that joins the first sheet and the second sheet and a portion that joins opposing surfaces of the folded bottom sheet, the first bottom seal portion is a portion that joins the first sheet and the bottom sheet, and includes first left and right bottom side seal portions and a substantially linear first bottom intermediate seal portion that is connected to the first left and right bottom side seal portions between the first left and right bottom side seal portions; The second bottom seal portion is a portion that joins the second sheet and the bottom sheet, and includes second left and right bottom side seal portions and a substantially linear second bottom intermediate seal portion that is connected to the second left and right bottom side seal portions between the second left and right bottom side seal portions, a widthwise length (A1) from the lower end of the inner edge of the portion of the left side seal portion where the opposing surfaces of the folded bottom sheet are joined to each other to an imaginary perpendicular line to the outer edge of the first or second bottom intermediate seal portion, including a portion where the inner edge of the first or second bottom side seal portion connected to the left side seal portion and the inner edge of the first or second bottom intermediate seal portion connected to that first or second bottom side seal portion intersect, and a widthwise length (A2) from the lower end of the inner edge of the portion of the right side seal portion where the opposing surfaces of the folded bottom sheet are joined to each other to an imaginary perpendicular line to the outer edge of the first or second bottom intermediate seal portion, including a portion where the inner edge of the first or second bottom side seal portion connected to that right side seal portion and the inner edge of the first or second bottom intermediate seal portion connected to that first or second bottom side seal portion intersect, The ratio of the length of A1, the width direction length (B) of the inner edge of the first or second bottom intermediate seal portion, and the length of A2 is 1:1:1 to 1:3:1. The steam release pouch is characterized by the above.

[0006] The invention described in claim 2 is The length of A1; The length of B; The length of A2; A height direction length (C) from the folded portion of the bottom sheet to the lower end of the bottom sheet, The relationship with the height direction length (D) of the substantially linear first or second bottom intermediate seal portion is (A1+B+A2)×2≧(C-D)×3.14×2 The steam release pouch according to claim 1,

[0007] The invention described in claim 3 is The length (E1) of the left side seal portion in the width direction is equal to the length (E2) of the right side seal portion in the width direction. 3. A steam release pouch according to claim 1 or 2.

[0008] The invention described in claim 4 is An opening guide portion is formed in a part of the left or right side seal portion, The opening guide portion is provided between the steam release portion and the folded portion of the bottom sheet. 4. A steam release pouch according to any one of claims 1 to 3.

[0009] The invention described in claim 5 is The length of C; The relationship between the length (F) in the height direction from the opening guide portion to the lower end of the bottom sheet, C×2≦F 5. The steam release pouch according to claim 2, wherein Effect of the Invention

[0010] With the steam release pouch of the present invention, the widthwise lengths (A1 and A2) of the left and right bottom side seal portions are made equal, and the ratio of the widthwise length (A1) of the bottom side seal portion to the widthwise length (B) of the inner edge of the bottom intermediate seal portion to the widthwise length (A2) of the bottom side seal portion is set to 1:1:1 to 1:3:1, thereby improving the bottom opening property. In addition, when a closed steam release pouch is heated in a microwave oven or the like, the internal pressure of the steam release pouch increases due to steam generated from the contents, etc., causing the storage section of the steam pouch to expand significantly. In this case, the steam release pouch can be prevented from bursting by venting the steam from the steam release section. Furthermore, improved bottom opening properties also improve the opening properties when opened after heat treatment, making it easy to remove the contents and making it easier to eat the food contents directly from the steam release pouch by using the steam release pouch as a container without transferring the food to tableware. [Brief description of the drawings]

[0011] [Figure 1] FIG. 2 is a front view of the steam release pouch before the opening is closed. [Diagram 2] FIG. 2 is a front view of the steam release pouch after the opening has been closed. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, an embodiment of a steam release pouch 100 according to the present invention will be described with reference to the drawings as necessary.

[0013] Fig. 1 is a front view of the steam release pouch 100 before the opening 30 is closed. Fig. 2 is a front view of the steam release pouch 100 after the opening 30 is closed. Fig. 1 shows a state in which the contents 200 are not contained, and Fig. 2 shows a state in which the contents 200 are contained and the opening 30 is closed.

[0014] The steam release pouch 100 includes a first sheet 11 and a second sheet 12 facing each other, and a bottom sheet 13 that is folded in a V-shape in a side view between the first sheet 11 and the second sheet 12. The steam release pouch 100 shown in Figs. 1 and 2 is composed of a single sheet. The opposed first sheet 11 and second sheet 12 are formed by folding the single sheet, and the bottom sheet 13 is disposed at the bottoms 11A, 12A of the first sheet 11 and the second sheet 12. Unlike the steam release pouch 100 shown in Figs. 1 and 2, the first sheet 11, the second sheet 12, and the bottom sheet 13 may be formed separately, and may be composed of three sheets.

[0015] The foodstuff that is the content 200 is, for example, a fluid foodstuff such as stew or soup.

[0016] The outer shape of the steam release pouch 100 as viewed from the front can be selected arbitrarily, and examples of such shapes include an inverted trapezoid and a square, in addition to the rectangle shown in Fig. 1. The width and height of the entire steam release pouch 100 are preferably determined based on, for example, the amount of contents 200 to be contained and ease of carrying. Here, the width direction is a direction substantially parallel to the outer edges 23Cb, 24Cb of the substantially linear first or second bottom intermediate seal portion 23C, 24C described below. The height direction is a direction perpendicular to the width direction.

[0017] The steam release pouch 100 is formed with left and right side seal portions 21, 22, a first bottom seal portion 23, and a second bottom seal portion 24. The portion surrounded by the seal portions 21-24 and the closing seal portion 25 that closes the opening 30 forms the storage portion 40. The left and right side seal portions 21, 22 include portions 21A, 22A that join the first sheet 11 and the second sheet 12, and portions 21B, 22B that join the opposing surfaces of the folded bottom sheet 13. Here, the left and right of the left and right side seal portions 21, 22 refer to the left and right of the first sheet 11 when the first sheet 11 is viewed as the front as shown in FIG. 1.

[0018] The portions 21A, 22A joining the first sheet 11 and the second sheet 12 in the left and right side seal portions 21, 22 are provided in a substantially linear manner along the left and right edges of the first sheet 11 and the second sheet 12 from the opening 30 to the fold-in portion 50 of the bottom sheet 13, for example, as shown in Fig. 1. The portions 21B, 22B joining the opposing surfaces of the folded bottom sheet 13 in the left and right side seal portions 21, 22 are provided in a substantially linear manner, for example, as shown in Fig. 1, along the left and right edges of the folded bottom sheet 13 and connected to the portions 21A, 22A joining the first sheet 11 and the second sheet 12 in the left and right side seal portions 21, 22. Here, the fold-in portion 50 of the bottom sheet 13 includes the portion where the inner edge 21Aa, 22Aa of the portion 21A, 22A where the first sheet 11 and the second sheet 12 in the left or right side seal portion 21, 22 intersects with the inner edge 23Aa, 24Aa, 23Ba, 24Ba of the first or second bottom side seal portion 23A, 24A, 23B, 24B connected to the portion 21A, 22A where the first sheet 11 and the second sheet 12 are joined. Here, the inner edge refers to the edge on the inner side of the steam release pouch 100.

[0019] The first bottom seal portion 23 is a portion that joins the first sheet 11 and the bottom sheet 13, and includes first left and right bottom side seal portions 23A, 23B and a substantially linear first bottom intermediate seal portion 23C that is connected to the first left and right bottom side seal portions 23A, 23B between the first left and right bottom side seal portions 23A, 23B. Here, the left and right of the first left and right bottom side seal portions 23A, 23B refer to the left and right of the first sheet 11 when the first sheet 11 is viewed as the front as shown in FIG.

[0020] The first left bottom side seal portion 23A includes a portion formed diagonally from the left side seal portion 21 to the first bottom intermediate seal portion 23C, and the first right bottom side seal portion 23B includes a portion formed diagonally from the right side seal portion 22 to the first bottom intermediate seal portion 23C.

[0021] 1, the first left and right bottom side seal portions 23A, 23B include portions formed obliquely from the left and right side seal portions 21, 22 to the first bottom intermediate seal portion 23C so as to be continuous with the lower ends of the portions 21A, 22A in the left and right side seal portions 21, 22 that join the first sheet 11 and the second sheet 12. The lower end of the inner edge 21Aa of the portion 21A that joins the first sheet 11 and the second sheet 12 in the left side seal portion 21 is continuous with the upper end of the inner edge 23Aa of the first left bottom side seal portion 23A, and the lower end of the inner edge 22Aa of the portion 22A that joins the first sheet 11 and the second sheet 12 in the right side seal portion 22 is continuous with the upper end of the inner edge 23Ba of the first right bottom side seal portion 23B. The inner edges 21Aa, 22Aa of the portions 21A, 22A joining the first sheet 11 and the second sheet 12 in the left and right side seal portions 21, 22 and the inner edges 23Aa, 23Ca, 23Ba of the first bottom seal portion 23 define the outer contour of the inner part of the steam release pouch 100 when viewed from the front before it is opened.

[0022] The second bottom seal portion 24, like the first bottom seal portion 23, has the following structure. The second bottom seal portion 24 is a portion that joins the first sheet 11 and the bottom sheet 13, and includes second left and right bottom side seal portions 24A, 24B and a substantially linear second bottom intermediate seal portion 24C that is connected to the second left and right bottom side seal portions 24A, 24B between the second left and right bottom side seal portions 24A, 24B. Here, the left and right of the second left and right bottom side seal portions 24A, 24B refer to the left and right of the second sheet 12 when the second sheet 12 is viewed as the front as shown in FIG.

[0023] The second left bottom side seal portion 24A includes a portion formed diagonally from the right side seal portion 22 to the second bottom intermediate seal portion 24C, and the second right bottom side seal portion 24B includes a portion formed diagonally from the left side seal portion 21 to the second bottom intermediate seal portion 24C.

[0024] 1, the second left and right bottom side seal portions 24A, 24B include portions formed obliquely from the right and left side seal portions 22, 21 to the second bottom intermediate seal portion 24C so as to be continuous with the lower ends of the portions 22A, 21A in the right and left side seal portions 22, 21 that join the first sheet 11 and the second sheet 12. The lower end of the inner edge 22Aa of the portion 22A that joins the first sheet 11 and the second sheet 12 in the right side seal portion 22 is continuous with the upper end of the inner edge 24Aa of the second left bottom side seal portion 24A, and the lower end of the inner edge 21Aa of the portion 21A that joins the first sheet 11 and the second sheet 12 in the left side seal portion 21 is continuous with the upper end of the inner edge 24Ba of the second right bottom side seal portion 24B. The inner edges 22Aa, 21Aa of the portions 22A, 21A joining the first sheet 11 and the second sheet 12 in the right and left side seal portions 22, 21 and the inner edges 24Aa, 24Ca, 24Ba of the second bottom seal portion 24 define the outer contour of the inner part of the steam release pouch 100 when viewed from the front before it is opened.

[0025] 1 and 2, the first sheet 11 and the second sheet 12 have the same shape, and the bottom seal portion 23 joining the first sheet 11 and the bottom sheet 13 has the same shape as the bottom seal portion 24 joining the second sheet 12 and the bottom sheet 13. Furthermore, the shapes of the first left bottom side seal portion 23A and the first right bottom side seal portion 23B are symmetrical, and the shapes of the second left bottom side seal portion 24A and the second right bottom side seal portion 24B are also symmetrical.

[0026] 2, when contents 200 are contained, the containing portion 40 expands and the fold-in portion 50 of the bottom sheet 13 is unfolded. The left side seal portion 21 and the right side seal portion 22 are spaced apart in the height direction from the bottom sheet 13 toward the opening 30 in a front view. As another example, the left side seal portion 21 and the right side seal portion 22 may be formed parallel to each other in the height direction.

[0027] A1 in Fig. 1 indicates the widthwise length from the lower end (h in Fig. 1) of the inner edge 21Ba of the portion 21B in the left side seal portion 21 where the opposing surfaces of the folded bottom sheet 13 are joined to each other to an imaginary perpendicular line 26 to the outer edges 23Cb, 24Cb of the first or second bottom intermediate seal portion 23C, 24C, including the portion (i in Fig. 1) where the inner edges 23Aa, 24Ba of the first or second bottom side seal portion 23A, 24B connected to the left side seal portion 21 intersect with the inner edges 23Ca, 24Ca of the first or second bottom intermediate seal portion 23C, 24C connected to the first or second bottom side seal portion 23A, 24B. Here, the outer edge refers to the edge on the outer side of the steam release pouch 100.

[0028] 1 indicates the widthwise length from the lower end (j in FIG. 1) of the inner edge 22Ba of the portion 22B of the right side seal portion 22 that joins the opposing surfaces of the folded bottom sheet 13 to the imaginary perpendicular line 26 to the outer edge 23Cb, 24Cb of the first or second bottom intermediate seal portion 23C, 24C, including the portion (k in FIG. 1) where the inner edge 23Ba, 24Aa of the first or second bottom side seal portion 23B, 24A that is connected to the right side seal portion 22 intersects with the inner edge 23Ca, 24Ca of the first or second bottom intermediate seal portion 23C, 24C that is connected to the first or second bottom side seal portion 23B, 24A. The lengths A1 and A2 are equal.

[0029] Furthermore, the ratio of the length of A1 to the widthwise length (B) of the inner edge 23Ca, 24Ca of the first or second bottom intermediate seal portion 23C, 24C to the length of A2 is 1:1:1 to 1:3:1. By setting the length ratio of A1, B, and A2 as described above, the first or second left and right bottom seal portions 23A, 24B, 23B, and 24A do not recede during heating treatment in a microwave oven or the like, and the bottom can be opened more widely.

[0030] The relationship between the length of A1, the length of B, the length of A2, the height direction length (C) from the folded-in portion 50 of the bottom sheet 13 to the lower end of the bottom sheet 13, and the height direction length (D) of the substantially linear first or second bottom intermediate seal portion 23C, 24C is preferably (A1+B+A2)×2≧(CD)×3.14×2. The reason is that if the maximum outer circumference of the bottom of the storage portion 40 is not greater than the opening of the bottom sheet 13, there is a risk that the portion (i in FIG. 1) where the inner edge 23Aa, 24Ba of the first or second bottom side seal portion 23A, 24B and the inner edge 23Ca, 24Ca of the first or second bottom intermediate seal portion 23C, 24C connected to the first or second bottom side seal portion 23A, 24B intersect may recede. Here, the lower end of the bottom sheet 13 is the lowest part of the bottom sheet 13 in the height direction. In FIG. 1, the lower end of bottom sheet 13 becomes the lower end of first or second bottom intermediate seal portion 23C, 24C.

[0031] The widthwise length (E1) of the left side seal portion 21 is equal to the widthwise length (E2) of the right side seal portion 22. At least when the steam release pouch 100 is heat-treated and used as a container after opening, the opening becomes symmetrical, making it easy to eat.

[0032] Furthermore, the steam release pouch 100 includes a steam release section 60 for releasing steam generated from the contents 200 and the like. This steam release section 60 is configured to open with an increase in pressure in the storage section 40 when the closed seal section 25 is formed, and to release steam from the contents 200 and the like to the outside. The shape of the steam release section 60 may be various. For example, the steam release section 60 constitutes a part of either or both of the left and right side seal sections 21, 22. It may be independent of the left or right side seal section 21, 22 and be an inner part of the first sheet 11 or the second sheet 12. The steam release section 60 shown in FIG. 1 has a seal part that is recessed from the outside to the inside in the width direction in a part of the part 21A, 22A that joins the first sheet 11 and the second sheet 12 in the right side seal section 22. The seal strength of this seal part that is recessed from the outside to the inside in the width direction is weaker than that of the side seal part that is connected to this seal part. The tip of the steam release section 60, which is the innermost part in the width direction, is provided in a position on each of the first sheet 11 and the second sheet 12 where strong pressure concentration occurs when the pressure in the storage section 40 increases. When the pressure in the storage section 40 increases to a pressure within a predetermined pressure range, the steam release section 60 opens. Specifically, as the pressure in the storage section 40 increases, the first sheet 11 and the second sheet 12, which are joined at the tip of the steam release section 60, peel off, and a steam release passage that communicates between the storage section 40 and the outside is formed in the steam release section 60. Steam is released by heating in a microwave oven or the like, the pressure increase in the storage section 40 is suppressed, and the steam release pouch 100 is prevented from bursting.

[0033] In addition, an opening guide portion 70 is formed in a part of the left or right side seal portion 21, 22. The opening guide portion 70 is provided between the steam release portion 60 and the folded portion 50 of the bottom sheet 13. When the closed steam release pouch 100 is heated, the portion between the steam release portion 60 and the bottom sheet 13 in the height direction of the first sheet 11 or the second sheet 12 is greatly expanded by steam generated from the contents 200, etc. By tearing the greatly expanded portion of the first sheet 11 or the second sheet 12, the contents 200 can be easily taken out while maintaining a wider opening width. In addition, the opening guide portion 70 is preferably formed at a position close to the steam release portion 60 in the height direction. This is because a large amount of contents 200 can be accommodated in the storage portion 40. In FIG. 1, the opening guide portion 70 is formed only in the left side seal portion 21, but it may be formed only in the right side seal 22 or both the left and right side seal portions 21, 22.

[0034] The relationship between the length C and the height direction length (F) from the opening guide portion 70 to the lower end of the bottom sheet 13 is preferably C×2≦F, taking into account the balance between the opening width and the liquid level of the contents.

[0035] The opening guide portion 70 may be, for example, a triangular cutout that narrows toward the inner edge 21A of the left side seal portion 21, as shown in Fig. 1. In Fig. 1, a gripping portion 71 is also provided to pinch the opening guide portion 70. The opening guide portion 70 may be, for example, a notch or cutout other than the cutout shown in Fig. 1.

[0036] Furthermore, an opening guide line such as a perforation may be provided starting from the opening guide portion 70. For example, the opening guide line starts from the opening guide portion 70 formed in one side seal portion and is formed horizontally until it reaches the other side seal portion. The large bulging portions of the first sheet 11 and the second sheet 12 can be easily torn along the opening guide line, and the contents 200 can be easily removed.

[0037] In addition, when the steam release pouch is made of a single sheet, the first and second bottom intermediate seal portions do not have to be provided. In this case, the following applies.

[0038] The first bottom seal portion does not include a first bottom middle seal portion 23C, but only includes first left and right bottom side seal portions.

[0039] The first left bottom side seal portion includes a portion formed diagonally from the left side seal portion 21 to the lower end of the bottom sheet 13, and the first right bottom side seal portion includes a portion formed diagonally from the right side seal portion 22 to the lower end of the bottom sheet 13.

[0040] The first left and right bottom side seal portions include, for example, portions formed obliquely from each of the left and right side seal portions 21, 22 to the lower end of the bottom sheet 13 so as to be continuous with the lower ends of portions 21A, 22A in the left and right side seal portions 21, 22 that join the first sheet 11 and the second sheet 12. The inner edges 21Aa, 22Aa of portions 21A, 22A that join the first sheet 11 and the second sheet 12 in the left and right side seal portions 21, 22, the inner edge of the first bottom seal portion 23, and the lower end of the bottom sheet 13 define the outer contour of the inner part of the steam release pouch 100 before it is opened, as viewed from the front.

[0041] The second bottom seal portion 24, like the first bottom seal portion 23, has the following structure. The second bottom seal does not include a second bottom middle seal portion 24C, but only includes second left and right bottom side seal portions.

[0042] The second left bottom side seal portion includes a portion formed diagonally from the right side seal portion 22 to the lower end of the bottom sheet 13, and the second right bottom side seal portion includes a portion formed diagonally from the left side seal portion 21 to the lower end of the bottom sheet 13.

[0043] The second left and right bottom side seal portions include, for example, portions formed obliquely from each of the right and left side seal portions 22, 21 to the lower end of the bottom sheet 13 so as to be continuous with the lower ends of portions 22A, 21A in the left and right side seal portions 22, 21 that join the first sheet 11 and the second sheet 12. The inner edges 22Aa, 21Aa of portions 22A, 21A that join the first sheet 11 and the second sheet 12 in the right and left side seal portions 22, 21, the inner edge of the second bottom seal portion 24, and the lower end of the bottom sheet 13 define the outer contour of the inner part of the steam release pouch 100 before it is opened, as viewed from the front.

[0044] Even when the first and second bottom intermediate seal portions 23C, 24C are not provided as described above, the steam release pouch has the same shapes for the first sheet 11 and the second sheet 12, and the shape of the bottom seal portion 23 joining the first sheet 11 and the bottom sheet 13 is the same as the shape of the bottom seal portion 24 joining the second sheet 12 and the bottom sheet 13. Furthermore, the shapes of the first left bottom side seal portion and the first right bottom side seal portion are symmetrical, and the shapes of the second left bottom side seal portion and the second right bottom side seal portion are also symmetrical.

[0045] In addition, A3 is the widthwise length from the lower end of the inner edge 21Ba of the portion 21B in the left side seal portion 21 that joins the opposing surfaces of the folded bottom sheet 13 to an imaginary perpendicular line to the lower end of the bottom sheet 13, including the portion where the inner edge of the first or second bottom side seal portion connected to the left side seal portion 21 intersects with the lower end of the bottom sheet 13.

[0046] In addition, A4 is the widthwise length from the lower end of the inner edge 22Ba of the portion 22B in the right side seal portion 22 that joins the opposing surfaces of the folded bottom sheet 13 to an imaginary perpendicular line to the lower end of the bottom sheet 13, including the portion where the inner edge of the first or second bottom side seal portion connected to the right side seal portion 22 intersects with the lower end of the bottom sheet 13.

[0047] Furthermore, the widthwise length of the portion where the first left bottom side seal portion and the lower end of the bottom sheet 13 intersect and the portion where the first right bottom side seal portion and the lower end of the bottom sheet 13 intersect, or the portion where the second left bottom side seal portion and the lower end of the bottom sheet 13 intersect and the portion where the second right bottom side seal portion and the lower end of the bottom sheet 13 intersect, is defined as B1.

[0048] Furthermore, the length ratio of A3, B1 and A4 is 1:1:1 to 1:3:1. By setting the length ratio of A3, B1 and A4 as described above, the first or second left and right bottom seal parts do not recede during heating treatment in a microwave oven or the like, and the bottom can be opened more widely.

[0049] The relationship between the length of A3, the length of B1, the length of A4, and the length (C) in the height direction from the fold-in portion 50 of the bottom sheet 13 to the bottom end of the bottom sheet 13 is preferably (A1+B+A2)×2≧C×3.14×2. The reason is that if the maximum circumference of the bottom of the storage portion 40 is not greater than the opening of the bottom sheet 13, there is a risk that the portion where the first or second left bottom side seal portion and the bottom end of the bottom sheet 13 intersect, or the portion where the first or second right bottom side seal portion and the bottom end of the bottom sheet 13 intersect, may recede. Here, the bottom end of the bottom sheet 13 refers to the lowest portion of the bottom sheet 13 in the height direction.

[0050] Each of the first sheet 11, the second sheet 12, and the bottom sheet 13 has a layer structure in which a plurality of layers are laminated. The layer structure of each of the sheets 11 to 13 can be selected arbitrarily. Each of the sheets 11 to 13 may all have the same layer structure, or the first sheet 11 and the second sheet 12 may have the same layer structure and the bottom sheet 13 may have a layer structure different from the first sheet 11 and the second sheet 12, or each of the sheets 11 to 13 may all have different layer structures. Each of the sheets 11 to 13 of the steam release pouch 100 shown in FIG. 1 all has the same layer structure.

[0051] Each of the sheets 11 to 13 includes, for example, an outermost layer, an intermediate layer, a sealant layer, a first adhesive layer, and a second adhesive layer. Each of the sheets 11 to 13 can be manufactured by, for example, a dry lamination method, an extruder method, a thermal lamination method, or the like. The first adhesive is provided between the outermost layer and the intermediate layer so as to bond the outermost layer and the intermediate layer. The second adhesive layer is provided between the intermediate layer and the sealant layer so as to bond the intermediate layer and the sealant layer.

[0052] The outermost layer is mainly excellent in gas barrier properties, printability, and heat resistance. The outermost layer is, for example, a transparent vapor deposition layer. An example of a material constituting the outermost layer is polyethylene terephthalate (hereinafter referred to as "transparent vapor deposition PET") on which an inorganic thin film is vapor deposited. The intermediate layer is mainly excellent in heat resistance and moisture resistance. An example of a material constituting the intermediate layer is nylon. In a more preferred example, the material constituting the intermediate layer is nylon (hereinafter referred to as "straight cut NY") which has excellent tearability in the resin flow direction. Hereinafter, the resin flow direction of the material constituting the first sheet 11 and the second sheet 12 is referred to as the MD (Machine Direction) direction, and the direction perpendicular to the MD direction is referred to as the TD (Transverse Direction) direction. The MD direction of the first sheet 11 and the second sheet 12 is the direction along the width direction. The TD direction of the first sheet 11 and the second sheet 12 is the direction along the height direction. An example of a material constituting the first adhesive layer is a polyester-based adhesive. An example of a material constituting the second adhesive layer is a polyester-based adhesive.

[0053] The sealant layer is excellent in heat resistance, heat sealability, and impact resistance. One example of the material constituting the sealant layer is non-oriented polypropylene (hereinafter referred to as "straight-cut CPP") with excellent tearability in the MD direction. "Excellent tearability in the MD direction" refers to, for example, a tear strength of 1.2 N or less according to the trouser tear method specified in JIS standard K7128-1. In the trouser tear method, a rectangular test piece with a length of 50 mm in the TD direction and a length of 150 mm in the MD direction is cut with a length of 75 mm in the center, and the tear strength in the MD direction is measured at a speed of 200 mm / min in a thermostatic chamber at 23°C. For example, the straight-cut CPP contains 3 to 10 parts by weight of low-crystalline ethylene elastomer for 100 parts by weight of propylene-ethylene block copolymer. The low crystalline ethylene elastomer has, for example, a density in the range of 0.865 to 0.890 g / cm3, and an endothermic heat upon melting, as specified by JIS standard K7122, in the range of 5 to 30 J / g.

[0054] Examples of uses for the steam release pouch 100 include the following. The steam release pouch 100 containing the foodstuff as the content 200 is heated in, for example, a microwave oven. As the pressure in the storage section 40 increases, the steam release section 60 opens, and steam generated from the content 200 and the like is discharged from the steam release section 60 to the outside, suppressing the increase in pressure in the storage section 40 and preventing the steam release pouch 100 from bursting. After the heat treatment, the pouch is opened from the opening guide section 70 by holding the grip section 71 sandwiched by the opening guide section 70 formed in the left side seal section 21. The predetermined dimensions of the bottom seal sections 23, 24 improve the bottom opening property, so that the first sheet 11 and the second sheet 12 are torn in a state where they are further apart, and therefore it is necessary to increase the tear strength. However, by including a sealant layer made of a material with excellent tearability in the MD in the first sheet 11 and the second sheet 12 as described above, the first sheet 11 and the second sheet 12 can be easily torn apart even when the storage section 40 is in an expanded state. By tearing the first sheet 11 and the second sheet 12 apart, the steam release pouch 100 is separated into an upper and lower part, and the lower part of the steam release pouch 100, including the bottom sheet 13, can be used as a container to easily remove the food, which is the content 200. Furthermore, the predetermined dimensions of the bottom seal portions 23, 24 improve the bottom opening property, which also improves the opening property when opening, making it easier to eat the stored food as is after opening. EXAMPLES

[0055] 1. Evaluation test of bottom opening property etc. regarding the formation of bottom seal part In both of the following Examples 1A to 3A and Comparative Examples 1A to 7A, the steam release pouch 100 shown in FIG. 1 was used. The steam release pouch 100 contained 100g of curry as the contents 200, and was heated in a microwave oven at 600W for 1 minute. In both of the following Examples 1A to 3A and Comparative Examples 1A to 7A, the first sheet 11, the second sheet 12, and the bottom sheet 13 all had the same layer structure, and the layer structure of each sheet was, from the outermost layer side, a layer structure of transparent vapor-deposited PET (polyethylene terephthalate vapor-deposited with an inorganic thin film) (12μm) / polyethylene terephthalate (12μm) / heat-resistant non-oriented polypropylene (straight-cut CPP) (60μm). In both of the following Examples 1A to 3A and Comparative Examples 1A to 7A, the steam release pouch 100 used had a maximum length of 158mm in the height direction when viewed from the front, and a maximum length of 150mm in the width direction when viewed from the front.

[0056] Example 1A A steam release pouch 100 was used in which B, A1, and A2 were all equal in length to 44.66 mm, E1 and E2 were equal in length to 8 mm, and the length of C minus the length of D was 85 mm.

[0057] Example 2A A steam release pouch 100 was used in which B was 67 mm, the lengths of A1 and A2 were both 33.5 mm, the lengths of E1 and E2 were both 8 mm as in Example 1, and the length of C minus the length of D was 85 mm as in Example 1A.

[0058] Example 3A A steam release pouch 100 was used in which B was 80.4 mm, the lengths of A1 and A2 were both 26.8 mm, the lengths of E1 and E2 were also equal and 8 mm as in Example 1, and the length of C minus the length of D was 85 mm as in Example 1A.

[0059] <Comparative Example 1A> A steam release pouch 100 was used in which the lengths of B, A1, and A2 were all equal and 44.66 mm as in Example 1A, the length of E1 was 8 mm as in Example 1A, the length of E2 was 6 mm, and the length of C minus the length of D was 85 mm as in Example 1A.

[0060] <Comparative example 2A> The lengths of B, A1, and A2 were the same as in Example 2A, with B being 67 mm, A1 and A2 being equal in length to 33.5 mm, E1 being 8 mm as in Example 1A, E2 being 6 mm, and the length of C minus the length of D being 85 mm as in Example 1A. A steam release pouch 100 was used.

[0061] <Comparative example 3A> The lengths of B, A1, and A2 were the same as in Example 3A, with the length of B being 80.4 mm, the lengths of A1 and A2 being equal at 26.8 mm, the length of E1 being 8 mm as in Example 1A, the length of E2 being 6 mm, and the length of C minus the length of D being 85 mm as in Example 1A. A steam release pouch 100 was used.

[0062] <Comparative example 4A> The length of B was 26.8, the lengths of A1 and A2 were equal to 53.6, the lengths of E1 and E2 were equal and 8 mm as in Example 1A, and the length of C minus the length of D was 85 mm as in Example 1A.

[0063] <Comparative example 5A> The length of B was 89.33, the lengths of A1 and A2 were equal to 22.33, the lengths of E1 and E2 were equal and 8 mm as in Example 1A, and the length of C minus the length of D was 85 mm as in Example 1A.

[0064] <Comparative Example 6A> The length of B was 134, the lengths of A1 and A2 were both 0, the lengths of E1 and E2 were both 8 mm as in Example 1A, and the length of C minus the length of D was 85 mm as in Example 1A.

[0065] <Comparative example 7A> The length of B was 0, the lengths of A1 and A2 were both 67, the lengths of E1 and E2 were both 8 mm as in Example 1A, and the length of C minus the length of D was 85 mm as in Example 1A. A steam release pouch 100 was used.

[0066] <Evaluation> Using the above-mentioned Examples 1A to 3A and Comparative Examples 1A to 7A, "presence or absence of recession of the first or second left and right bottom seal parts 23A, 24B, 23B, 24A during heat treatment" (referred to as "presence or absence of recession of the left and right bottom seal parts" in Table 1), "bottom openability after heat treatment" (referred to as "bottom openability" in Table 1), and "opening width after opening" (referred to as "opening width" in Table 1) were evaluated. The results are shown in Table 1. In Table 1, in "presence or absence of recession of the left and right bottom seal parts," if recession of the first or second left and right bottom seal parts 23A, 24B, 23B, 24A did not occur, it was recorded as "none," and if recession of the first or second left and right bottom seal parts 23A, 24B, 23B, 24A occurred, it was recorded as "present" (if recession occurred slightly, it was recorded as "slightly present"). In Table 1, the bottom opening property is indicated as "Good", the bottom opening property is indicated as "△" when it is edible but not sufficient, and the bottom opening property is indicated as "X" when it is poor. Also, "opening width after opening" is the maximum opening width when opened after opening.

[0067] In the "Overall Evaluation" in Table 1, a "Good" was recorded when there was no recession of the first or second left and right bottom seal portions 23A, 24B, 23B, 24A and the bottom opening properties were good, and an "X" was recorded when there was recession of the first or second left and right bottom seal portions 23A, 24B, 23B, 24A or the bottom opening properties were insufficient (△) or poor (X).

[0068] [Table 1]

[0069] As a result of the evaluation, in Examples 1A to 3A, the first or second left and right bottom seal parts 23A, 24B, 23B, 24A did not recede during microwave heating, and the bottom opening property was good. In addition, the opening widths of Examples 1A and 3A were 90 mm, and the opening width of Example 2A was 100 mm. On the other hand, in Comparative Examples 1A to 3A, the first or second left and right bottom seal parts 23A, 24B, 23B, 24A did not recede during microwave heating, but the bottom opening property was such that it was edible but not sufficient. In Comparative Example 4, the first or second left and right bottom seal parts 23A, 24B, 23B, 24A recede slightly during microwave heating, and the bottom opening property was good. In Comparative Example 5, the first or second left and right bottom seal parts 23A, 24B, 23B, 24A retreated during microwave heating, and the bottom opening was good. In Comparative Example 6A, the first or second left and right bottom seal parts 23A, 24B, 23B, 24A retreated during microwave heating, and the bottom opening was edible but not sufficient. In Comparative Example 7A, the first or second left and right bottom seal parts 23A, 24B, 23B, 24A retreated during microwave heating, and the bottom opening was poor. The opening widths of Comparative Examples 1A to 7A are as shown in Table 1.

[0070] From the above evaluation results, the overall evaluation was "good" for all of Examples 1A to 3A, and "poor" for all of Comparative Examples 1A to 7A.

[0071] Regarding the formation of the bottom seal portion, as described above, in Examples 1A to 3A and Comparative Examples 1A to 3A, the ratio of the length of A1 to the length of B to the length of A2 is within the range of 1:1:1 to 1:3:1. On the other hand, in Comparative Examples 4A to 7A, the ratio of the length of A1 to the length of B to the length of A2 is not within the range of 1:1:1 to 1:3:1. Also, in Examples 1A to 3A and Comparative Examples 4A to 7A, the lengths of E1 and E2 are equal, while in Comparative Examples 1A to 3A, the lengths of E1 and E2 are different.

[0072] Therefore, when the ratio of the length of A1 to the length of B to the length of A2 is within the range of 1:1:1 to 1:3:1 and the lengths of E1 and E2 are equal, the overall evaluation is "Good", that is, the first or second left and right bottom seal portions 23A, 24B, 23B, 24A do not recede during heating in a microwave oven and the bottom opens more widely. Note that it is necessary that the opening width and bottom openability are compatible.

[0073] 2. Evaluation test of cuttability etc. regarding the position of the opening guidance part In all of the following Examples 1B to 3B and Comparative Examples 1B and 2B, a steam release pouch was used that had an opening guide line such as a perforation starting from opening guide portion 70 of steam release pouch 100 shown in Fig. 1. This opening guide line starts from opening guide portion 70 formed in first side seal portion 21A and is formed horizontally until it reaches second side seal portion 22.

[0074] A steam release pouch containing 100 ml of water as the content 200 was heated in a microwave oven at 600 W for 1 minute 40 seconds. In addition, in the following Examples 1B to 3B and Comparative Examples 1B and 2B, the first sheet 11, the second sheet 12 and the bottom sheet 13 all have the same layer structure, and the layer configuration of each of the sheets 11 to 13 has a layer structure of gas barrier alumina vapor-deposited polyethylene terephthalate film ("GL-ARH" manufactured by Toppan Printing Co., Ltd. was used) (12 μm) / straight cut NY (15 μm) / unstretched polypropylene (straight cut CPP) ("ZK500R" manufactured by Toray Advanced Film Co., Ltd. was used) (60 μm) from the outermost layer side. In addition, in Examples 1B to 3B and Comparative Examples 1B and 2B, the maximum length in the height direction when viewed from the front was 158 mm, and the maximum length in the front direction was 158 mm. The steam release pouch used had a maximum widthwise length of 140 mm as viewed from the outside, a steam release portion 60 constituting a part of the right side seal portion 22, formed at a position 58 mm in height from the upper end of the outer edge of the right side seal portion 22, and a height direction length (C) from the fold-in portion 50 of the bottom sheet 13 to the lower end of the bottom sheet of 45 mm. Note that in all of Examples 1B to 3B and Comparative Examples 1B and 2B, an opening guide portion 70 is formed in the left side seal portion 21, but the position of the opening guide portion 70 is different for each. In Table 2, "position of opening guide portion 70" refers to the height direction length (F) from the opening guide portion 70 to the lower end of the bottom sheet 13.

[0075] Example 1B The steam release pouch 100 used had an opening guide portion 70 positioned at 90 mm.

[0076] <Example 2B> The steam release pouch 100 used had an opening guide portion 70 positioned at 80 mm.

[0077] <Example 3B> The steam release pouch 100 used had an opening guide portion 70 positioned at 72 mm.

[0078] <Comparative example 1B> The steam release pouch 100 used had an opening guide portion 70 positioned at 70 mm.

[0079] <Comparative Example 2B> The steam release pouch 100 used had an opening guide portion 70 positioned at 60 mm.

[0080] <Evaluation> Using the above Examples 1B to 3B and Comparative Examples 1B and 2B, the following were evaluated: "The opening width as viewed from the top immediately after opening after heat treatment and the opening width as viewed from the top 10 minutes after opening after heat treatment," "Ease of cutting when opening after heat treatment" (referred to as "Ease of cutting" in Table 2), "Risk of burns when removing contents 200" (referred to as "Risk of burns" in Table 2), and "Ease of inserting and removing containers when steam release pouch 100 is used as a container after opening" (referred to as "Inserting and removing containers" in Table 2).

[0081] The results are shown in Table 2. The above-mentioned "cuttability" indicates whether the first sheet 11 and the second sheet 12 were easily torn apart. In Table 2, for "cuttability", when the first sheet 11 and the second sheet 12 could be easily torn apart, it was marked "easy", when the first sheet 11 and the second sheet 12 could be torn apart but not easily, it was marked "fair", and when the first sheet 11 and the second sheet 12 could be torn apart but with difficulty, it was marked "difficult". In addition, for the "risk of burns" in Table 2, when there was a low risk of burns when removing the contents 200 from the steam release pouch 100 after the heat treatment, it was marked "low", when there was a slight risk of burns when removing the contents 200 from the steam release pouch 100 after the heat treatment, it was marked "slightly", and when there was a high risk of burns when removing the contents 200 from the steam release pouch 100 after the heat treatment, it was marked "high". Regarding "taking the container in and out" in Table 2, when steam release pouch 100 was used as a container after opening following heat treatment, the case where it was easy to take the container in and out was marked "easy," and when steam release pouch 100 was used as a container after opening following heat treatment, the case where it was not easy but possible to take the container in and out was marked "possible."

[0082] In addition, in the "Overall Evaluation" in Table 2, when the product is easy to cut, has a low risk of burns, and is possible or easy to take out and put back in, making it easy to eat, it is marked as "O", when it is inconvenient but possible to eat, it is marked as "△", and when it is impossible to eat, it is marked as "X".

[0083] [Table 2]

[0084] As a result of the evaluation, Example 2B was easy to cut, had a low risk of burns, and was in the range of possible to easy for inserting and removing dishes. On the other hand, Example 1B was easy to cut, had a low risk of burns, and was in the range of possible for inserting and removing dishes. Example 3B was in the range of possible to easy for cutting, had a slight risk of burns, and was easy to insert and remove dishes. Both Comparative Examples 1B and 2B were difficult to cut, had a high risk of burns, and were easy to insert and remove dishes.

[0085] From the above evaluation results, the overall evaluation was "good" for Example 2B, "fair" for Examples 1B and 3B, and "poor" for Comparative Examples 1B and 2B.

[0086] As can be seen from the above and Table 2, the closer the position of the opening guide portion 70 provided between the steam release portion 60 and the fold-in portion 50 of the bottom sheet 13 is to the upper end of the side seal portion 21 in relation to the widthwise length of the steam release pouch 100, the easier it is to cut the first sheet 11 and the second sheet 12, and the less likely it is that the heat or steam from the contents 200 will come into contact with the hands when removing the contents 100, thereby lowering the risk of burns. However, if the position of the opening guide portion 70 is too high in relation to the widthwise length of the steam release pouch 100, the steam release pouch 100 will be prone to bending and will not be suitable as a container. On the other hand, the lower the position of the opening guide portion 70 provided between the steam release portion 60 and the folded-in portion 50 of the bottom sheet 13 is relative to the widthwise length of the steam release pouch 100, that is, the closer it is to the lower end of the side seal portion 21, the more difficult it becomes to cut the first sheet 11 and the second sheet 12, and the more likely it is that the heat or steam of the contents 200 will come into contact with the hands when removing the contents 100, increasing the risk of burns. Also, the lower the position of the opening guide portion 70 is relative to the widthwise length of the steam release pouch 100, the less likely the steam release pouch 100 is to bend and the more stable it is, making it more suitable as a container. Thus, it was confirmed that there is a trade-off between the cuttability and the usability as a container.

[0087] As described above, with the steam release pouch of the present invention, the widthwise lengths (A1 and A2) of the left and right bottom side seal portions are made equal, and the ratio of the widthwise length (A1) of the bottom side seal portion to the widthwise length (B) of the inner edge of the bottom intermediate seal portion to the widthwise length (A2) of the bottom side seal portion is set to 1:1:1 to 1:3:1, thereby improving the bottom opening property. In addition, when a closed steam release pouch is heated in a microwave oven or the like, the internal pressure increases due to steam generated from the contents, causing the containing section to expand significantly. However, the steam can be released from the steam release section to prevent the steam release pouch from bursting. Furthermore, improved bottom opening properties also improve the opening properties when opened after heat treatment, making it easy to remove the contents and making it easier to eat the food contents directly from the steam release pouch by using the steam release pouch as a container without transferring the food to tableware. [Explanation of symbols]

[0088] 1st sheet....11 Bottom of 1st sheet: 11A 2nd sheet···12 Bottom of second sheet: 12A Bottom sheet··13 Left side seal part··21 The part joining the first and second sheets in the left side seal part 21A Inner edge of the left side seal portion where the first sheet and the second sheet are joined: 21Aa Inner edge of the left side seal portion where the opposing surfaces of the folded bottom sheet are joined: 21B Inner edge of the part where the opposing surfaces of the folded bottom sheet are joined together in the left side seal part... 21Ba The outer edge of the part where the opposing surfaces of the folded bottom sheet are joined together in the left side seal part 21Bb Right side seal part··22 The part joining the first and second sheets in the right side seal part: 22A Inner edge of the part of the right side seal where the first sheet and the second sheet are joined: 22Aa. Part of the right side seal where the opposing surfaces of the folded bottom sheet are joined: 22B. Inner edge of the part where the opposing surfaces of the folded bottom sheet are joined together in the right side seal part 22Ba The outer edge of the part where the opposing surfaces of the folded bottom sheet are joined together in the right side seal part 22Bb First bottom seal part 23 1st left bottom side seal part···23A Inner edge of first left bottom side seal part 23Aa 1st right bottom side seal part···23B Inner edge of the first right bottom side seal part 23Ba First bottom intermediate seal part···23C Inner edge of the first bottom intermediate seal part 23Ca Outer edge of first bottom intermediate seal part 23Cb Second bottom seal part 24 Second Left Bottom Side Seal Part···24A Second left bottom side seal part 24Aa Second Right Bottom Side Seal Part···24B Inner edge of second right bottom side seal part ···24Ba Second bottom intermediate seal part···24C Inner edge of second bottom intermediate seal part 24Ca Outer edge of second bottom mid-seal part 24Cb Closure seal part 25 Imaginary perpendicular line to the outer edge of the first or second bottom intermediate seal part 26 Openings 30 Storage area 40 Bottom sheet fold-in section···50 Steam release section··60 Opening guidance section...70 Knob 71 Steam release pouch ···100 Contents...200

Claims

1. A steam-venting pouch comprising a first sheet and a second sheet facing each other, and a bottom sheet interposed between the first sheet and the second sheet in a V-shape when viewed from the side, and equipped with a steam vent for discharging steam generated from the contents, Left and right side sealing portions, a first bottom sealing portion, and a second bottom sealing portion are formed. The left and right side sealing portions are linear in shape and include a portion that joins the first sheet and the second sheet, and a portion that joins the opposing surfaces of the folded bottom sheet. The first bottom seal portion is the portion that joins the first sheet and the bottom sheet, and includes a first left and right bottom side seal portion and a linear first bottom intermediate seal portion that connects to the first left and right bottom side seal portions between the first left and right bottom side seal portions, The second bottom seal portion is the portion that joins the second sheet and the bottom sheet, and includes a second left and right bottom side seal portion and a linear second bottom intermediate seal portion that connects to the second left and right bottom side seal portions between the second left and right bottom side seal portions, In the left side seal portion, the widthwise length (A1) from the lower end of the inner edge of the portion where the opposing surfaces of the folded bottom sheet are joined together to a virtual vertical line with respect to the outer edge of the first or second bottom intermediate seal portion, including the portion where the inner edge of the first or second bottom side seal portion connected to the left side seal portion intersects with the inner edge of the first or second bottom intermediate seal portion connected to the first or second bottom side seal portion, is equal to the widthwise length (A2) from the lower end of the inner edge of the portion where the opposing surfaces of the folded bottom sheet are joined together to a virtual vertical line with respect to the outer edge of the first or second bottom intermediate seal portion, including the portion where the inner edge of the first or second bottom side seal portion connected to the right side seal portion intersects with the inner edge of the first or second bottom intermediate seal portion connected to the first or second bottom side seal portion, The ratio of the length of A1, the widthwise length of the inner edge of the first or second bottom intermediate seal portion (B), and the length of A2 is 1:1:1 to 1:3:

1. The widthwise length (E1) of the left side seal portion is equal to the widthwise length (E2) of the right side seal portion. Each of the first sheet, the second sheet, and the bottom sheet has a layered structure in which multiple layers, including an outermost layer, an intermediate layer, and a sealant layer, are laminated together. The surface defining the space for containing the contents is formed by the sealant layer, An opening guide portion is formed in a part of the left or right side seal portion. The opening guide portion is provided between the steam vent portion and the folded portion of the bottom sheet. The ratio of the length from the lower end of the bottom sheet to the position of the opening guide to the width of the steam vent pouch is 72 / 140 to 90 / 140. A steam-venting pouch characterized by the following features.

2. The relationship between the length in the height direction from the folded portion of the bottom sheet to the lower end of the bottom sheet (C) and the length in the height direction from the opening guide portion to the lower end of the bottom sheet (F) is, C × 2 ≤ F The steam-venting pouch according to claim 1, characterized in that it is the same as the one described in claim 1.

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