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 used for heating food or the like in a microwave oven or the like. [Background technology]

[0002] BACKGROUND ART Conventionally, steam release pouches used for heating food or the like in a microwave oven or the like have been known which have two opposing films, a bottom film, and a steam release section on the side. For example, Patent Document 1 describes a steam release pouch that has two opposing films and a bottom film sandwiched between them, with an opening means provided below a steam release section provided in a side seal. This steam release pouch allows the opening position to be closer to the contents, making it easier to remove the contents. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2018-127257 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 the 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 that has improved bottom opening properties, thereby improving opening properties, and that makes it easy to eat the food contents directly from the steam release pouch after opening it 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 being folded in a V-shape in a side view; and the pouch having a steam release section for releasing steam generated from contents, etc. The left and right side seals, the first bottom seal, and the second bottom seal are formed. the left and right side seal portions are substantially linear and include a portion joining the first sheet and the second sheet and a portion joining opposing surfaces of the folded bottom sheet together; the first bottom seal portion is a portion joining 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 between the first left and right bottom side seal portions and connected to the first left and right bottom side seal portions; the second bottom seal portion is a portion joining 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 between the second left and right bottom side seal portions and connected to the second left and right bottom side seal portions; the 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 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 that first or second bottom side seal portion, and the 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 the portion where the inner edge of the first or second bottom side seal portion connected to that right side seal portion intersects with the inner edge of the first or second bottom intermediate seal portion connected to that first or second bottom side seal portion, are equal; 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 between the length (D) in the height direction of the substantially linear first or second bottom intermediate seal portion is: (A1+B+A2)×2≧(CD)×3.14×2 The steam release pouch according to claim 1, characterized in that:

[0007] The invention described in claim 3 is The width direction length (E1) of the left side seal portion is equal to the width direction length (E2) of the right side seal portion. 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. 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 height direction length (F) 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 [Effects 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. Furthermore, when a closed steam release pouch is heated in a microwave oven or the like, the steam generated from the contents increases the internal pressure of the steam release pouch, causing the storage section of the steam pouch to expand significantly. In this case, the steam can be released from the steam release section to prevent the steam release pouch from bursting. Furthermore, improved bottom opening also improves opening when opened after heat treatment, making it easier to remove the contents and making it easier to eat the food contents directly from the steam release pouch using the pouch as a container without transferring them to tableware. [Brief explanation of the drawings]

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

[0012] Hereinafter, an embodiment of the 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 the state in which the contents 200 are not contained, and Fig. 2 shows the 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 side view and interposed 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 facing first sheet 11 and second sheet 12 are formed by folding the single sheet, and the bottom sheet 13 is formed and placed 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 food product that is the contents 200 is, for example, a fluid food product 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 include the rectangle shown in Fig. 1, an inverted trapezoid, a square, and the like. 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 portability. Here, the width direction refers to a direction substantially parallel to the outer edges 23Cb, 24Cb of the substantially linear first or second bottom intermediate seal portion 23C, 24C, which will be described later. The height direction refers to 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 area surrounded by these seal portions 21 to 24 and a 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] 1, portions 21A, 22A joining the first sheet 11 and the second sheet 12 in the left and right side seal portions 21, 22 are arranged in a substantially straight line 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. Portions 21B, 22B joining the opposing surfaces of the folded-in bottom sheet 13 in the left and right side seal portions 21, 22 are arranged in a substantially straight line along the left and right edges of the folded-in bottom sheet 13 and continuous with portions 21A, 22A joining the first sheet 11 and the second sheet 12 in the left and right side seal portions 21, 22, for example, as shown in FIG. Here, the fold-in portion 50 of the bottom sheet 13 includes the portion where the inner edges 21Aa, 22Aa of the portions 21A, 22A where the first sheet 11 and the second sheet 12 join in the left or right side seal portion 21, 22 intersect with the inner edges 23Aa, 24Aa, 23Ba, 24Ba of the first or second bottom side seal portion 23A, 24A, 23B, 24B that are connected to the portions 21A, 22A where the first sheet 11 and the second sheet 12 join. Here, the inner edges refer to the edges on the inner side of the steam release pouch 100.

[0019] The first bottom seal portion 23 is a portion joining 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 located between the first left and right bottom side seal portions 23A, 23B and connects to 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 diagonally from the left and right side seal portions 21, 22 to the first bottom intermediate seal portion 23C so as to connect to 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 in the left side seal portion 21 that joins the first sheet 11 and the second sheet 12 joins 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 in the right side seal portion 22 that joins the first sheet 11 and the second sheet 12 joins 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 opening.

[0022] The second bottom seal portion 24 has the same structure as the first bottom seal portion 23 described above. The second bottom seal portion 24 is the portion joining 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 located between the second left and right bottom side seal portions 24A, 24B and connects to 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 relative to the second sheet 12 when the second sheet 12 is viewed as the front as shown in FIG. 1.

[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 diagonally from the right and left side seal portions 22, 21 to the second bottom intermediate seal portion 24C so as to connect to 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 in the right side seal portion 22 that joins the first sheet 11 and the second sheet 12 joins 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 in the left side seal portion 21 that joins the first sheet 11 and the second sheet 12 joins with the upper end of the inner edge 24Ba of the second right bottom side seal portion 24B joins 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 opening.

[0025] The steam release pouch 100 shown in FIG. 1 and FIG. 2 is made up of a first sheet 11 and a second sheet 12. The shapes of bottom seal portion 23 joining first sheet 11 and bottom sheet 13 are the same as the shape of bottom seal portion 24 joining second sheet 12 and bottom sheet 13. Furthermore, the shapes of first left bottom side seal portion 23A and first right bottom side seal portion 23B are symmetrical, and the shapes of second left bottom side seal portion 24A and second right bottom side seal portion 24B are also symmetrical.

[0026] 2, when contents 200 are placed inside the steam release pouch 100, the containing section 40 expands and the fold-in section 50 of the bottom sheet 13 unfolds. The left side seal section 21 and the right side seal section 22 are spaced apart in the height direction in a front view from the bottom sheet 13 toward the opening 30. As another example, the left side seal section 21 and the right side seal section 22 may be formed parallel to each other in the height direction.

[0027] 1 indicates the widthwise length from the lower end (h in FIG. 1) of the inner edge 21Ba of the portion 21B of the left side seal portion 21 that joins the opposing surfaces of the folded bottom sheet 13 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 that are 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 that are 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 inner edge 22Ba of portion 22B of right side seal portion 22, which joins the opposing surfaces of folded bottom sheet 13, to an imaginary perpendicular line 26 to outer edge 23Cb, 24Cb of first or second bottom intermediate seal portion 23C, 24C, including the intersection (k in FIG. 1) of inner edge 23Ba, 24Aa of first or second bottom side seal portion 23B, 24A connected to right side seal portion 22 and inner edge 23Ca, 24Ca of first or second bottom intermediate seal portion 23C, 24C connected to 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, 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 lengths A1, B, and A2, the height dimension (C) from the fold-in portion 50 of the bottom sheet 13 to the bottom edge of the bottom sheet 13, and the height dimension (D) of the substantially linear first or second bottom intermediate seal portion 23C, 24C is preferably (A1 + B + A2) × 2 ≥ (CD) × 3.14 × 2. This is because if the maximum circumference of the bottom of the storage section 40 is not greater than the opening of the bottom sheet 13, there is a risk of the portion (i in FIG. 1) where the inner edge 23Aa, 24Ba of the first or second bottom side seal portion 23A, 24B intersects with 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 may recede. Here, the bottom edge of the bottom sheet 13 refers to the lowest portion of the bottom sheet 13 in the height direction. In FIG. 1, the lower end of the bottom sheet 13 is the lower end of the 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 then opened and used as a container, the opening becomes symmetrical, making it easier to eat.

[0032] The steam release pouch 100 further includes a steam release section 60 for releasing steam generated from the contents 200 and other materials. This steam release section 60 is configured to open in response to an increase in pressure in the storage section 40 when the closed seal section 25 is formed, allowing steam from the contents 200 and other materials to be released to the outside. The steam release section 60 may have various shapes. For example, the steam release section 60 may constitute part of one or both of the left and right side seal sections 21, 22. It may also be independent of the left or right side seal section 21, 22 and located on the inside of the first sheet 11 or second sheet 12. The steam release section 60 shown in FIG. 1 has a seal section that is recessed from the outside to the inside in the width direction at a portion of the right side seal section 22, part of the section 21A, 22A that joins the first sheet 11 and the second sheet 12. The seal strength of this seal section that is recessed from the outside to the inside in the width direction is weaker than that of the side seal section adjacent to this seal section. The tip of this steam release section 60, which is the innermost part in the width direction, is located 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 away, forming a steam release passage in the steam release section 60 that connects the storage section 40 to the outside. Heating in a microwave oven or the like releases steam, suppressing the increase in pressure in the storage section 40 and preventing the steam release pouch 100 from bursting.

[0033] Additionally, an opening guide portion 70 is formed in a portion 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 fold-in portion 50 of the bottom sheet 13. When the closed steam release pouch 100 is heated, steam generated from the contents 200 and the like significantly expands 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. By tearing this significantly expanded portion of the first sheet 11 or the second sheet 12, the contents 200 can be easily removed while maintaining a wider opening width. Furthermore, the opening guide portion 70 is preferably formed in a position close to the steam release portion 60 in the height direction. This is because a larger amount of contents 200 can be accommodated in the storage portion 40. Note that, although the opening guide portion 70 is formed only in the left side seal portion 21 in FIG. 1 , it may be formed only in the right side seal 22 or in 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] 1, the opening guide portion 70 may be a triangular cutout that narrows toward the inner edge 21A of the left side seal portion 21. 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 a cutout other than the cutout shown in FIG.

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

[0037] If 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 does not include a first bottom middle seal 23C, but includes only first left and right bottom side seals.

[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 in the left and right side seal portions 21, 22 that join the first sheet 11 and the second sheet 12, 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 when viewed from the front before opening.

[0041] The second bottom seal portion 24 has the same structure as the first bottom seal portion 23 described above. The second bottom seal does not include a second bottom middle seal 24C, but only includes second left and right bottom side seals.

[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 the right and left side seal portions 22, 21 to the lower end of the bottom sheet 13 so as to connect to the lower ends of the 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 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 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 when viewed from the front before opening.

[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, 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, is defined as A4.

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

[0048] Furthermore, the length ratio of A3 to B1 to A4 is 1:1:1 to 1:3:1. By setting the length ratio of A3 to B1 to A4 as described above, the first or second left and right bottom seal portions 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 height (C) from the fold-in portion 50 of the bottom sheet 13 to the bottom edge of the bottom sheet 13 is preferably (A1 + B + A2) × 2 ≥ C × 3.14 × 2. The reason for this is that if the maximum circumference of the bottom of the storage section 40 is not equal to or 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 and the bottom edge of the bottom sheet 13 intersect, or the portion where the first or second right bottom side seal and the bottom edge of the bottom sheet 13 intersect, may recede. Here, the bottom edge of the bottom sheet 13 refers to the lowest portion of the bottom sheet 13 in the height direction.

[0050] The first sheet 11, the second sheet 12, and the bottom sheet 13 each have a layer structure in which multiple layers are laminated. The layer structure of each of the sheets 11 to 13 can be selected arbitrarily. 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 those of the first sheet 11 and the second sheet 12, or the sheets 11 to 13 may all have different layer structures. The sheets 11 to 13 of the steam release pouch 100 shown in FIG. 1 all have 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 to bond them together. The second adhesive layer is provided between the intermediate layer and the sealant layer to bond them together.

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

[0053] The sealant layer has excellent heat resistance, heat sealability, and impact resistance. An example of a material for the adhesive layer is unstretched polypropylene (hereinafter referred to as "straight-cut CPP") with excellent tear strength in the MD direction. Excellent tear strength in the MD direction means, for example, that the tear strength is 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 50 mm long in the TD direction and 150 mm long in the MD direction is cut with a 75 mm cut 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. A straight-cut CPP is, for example, a CPP with low tear strength for 100 parts by weight of propylene-ethylene block copolymer. The low-crystalline ethylene elastomer is contained in a proportion of 3 to 10 parts by weight. The low-crystalline ethylene elastomer has a density of 0.865 to 0.890 g / cm. 3 and the endothermic heat at the time of melting as specified in JIS standard K7122 is 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, which contains the food product 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 other ingredients is released to the outside through the steam release section 60, thereby suppressing the increase in pressure in the storage section 40 and preventing the steam release pouch 100 from bursting. After the heating process, the pouch is opened from the opening guide section 70 by holding the tab section 71 held by the opening guide section 70 formed on the left side seal section 21. The predetermined dimensions of the bottom seal sections 23, 24 improve bottom opening properties, and the first and second sheets 11 and 12 are torn apart with a greater distance between them, necessitating increased 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 container 40 is expanded. Tearing the first sheet 11 and the second sheet 12 separates the steam release pouch 100 into upper and lower halves, 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 content 200. Furthermore, the predetermined dimensions of the bottom seal portions 23, 24 improve the bottom opening property, which also improves the ease of opening when opening, making it easier to eat the food stored therein after opening. [Example]

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

[0056] Example 1A A steam release pouch 100 was used in which B, A1, and A2 all had the same length of 44.66 mm, E1 and E2 had the same length of 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, A1 and A2 were both 33.5 mm in length, E1 and E2 were both 8 mm in length 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> The steam release pouch 100 used had B, A1, and A2 all having the same length, 44.66 mm, as in Example 1A, E1 having the same length as in Example 1A, 8 mm, E2 having the same length as in Example 1A, and C's length minus D's length being 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 and A1 and A2 being equal at 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.

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

[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 also 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 also 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 equal to 67, 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.

[0066] <Evaluation> Using the above Examples 1A to 3A and Comparative Examples 1A to 7A, the following were evaluated: "Whether or not the first or second left and right bottom seal portions 23A, 24B, 23B, 24A recedes during heat treatment" (referred to as "Whether or not the left and right bottom seal portions recedes" 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). The results are shown in Table 1. In Table 1, for "Whether or not the left and right bottom seal portions recedes," if no receding of the first or second left and right bottom seal portions 23A, 24B, 23B, 24A occurred, it was recorded as "None," and if receding of the first or second left and right bottom seal portions 23A, 24B, 23B, 24A occurred, it was recorded as "Yes" (or if slight receding occurred, it was recorded as "Slightly Yes"). In Table 1, good bottom-opening properties are indicated by "◯", edible but not sufficient bottom-opening properties are indicated by "△", and poor bottom-opening properties are indicated by "×". "Opening width after opening" refers to the maximum opening width when opened after opening.

[0067] In the "Overall Evaluation" in Table 1, if there is no recession of the first or second left and right bottom seal portions 23A, 24B, 23B, 24A and the bottom opening property is good, it is marked as "Good", and if there is recession of the first or second left and right bottom seal portions 23A, 24B, 23B, 24A or the bottom opening property is insufficient (△) or poor (×), it is marked as "Poor".

[0068] [Table 1]

[0069] The evaluation results showed that for Examples 1A to 3A, the first or second left and right bottom seal portions 23A, 24B, 23B, 24A did not recede during microwave heating, and the bottom-opening properties were good. Furthermore, the opening widths of Examples 1A and 3A were each 90 mm, and the opening width of Example 2A was 100 mm. Meanwhile, for Comparative Examples 1A to 3A, the first or second left and right bottom seal portions 23A, 24B, 23B, 24A did not recede during microwave heating, but the bottom-opening properties were edible but insufficient. For Comparative Example 4, the first or second left and right bottom seal portions 23A, 24B, 23B, 24A recede slightly during microwave heating, and the bottom-opening properties were good. In Comparative Example 5, the first or second left and right bottom seal portions 23A, 24B, 23B, 24A retracted during microwave heating, and the bottom-opening property was good. In Comparative Example 6A, the first or second left and right bottom seal portions 23A, 24B, 23B, 24A retracted during microwave heating, and the bottom-opening property was edible but insufficient. In Comparative Example 7A, the first or second left and right bottom seal portions 23A, 24B, 23B, 24A retracted during microwave heating, and the bottom-opening property 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, for 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 falls within the range of 1:1:1 to 1:3:1. On the other hand, for Comparative Examples 4A to 7A, the ratio of the length of A1 to the length of B to the length of A2 falls outside the range of 1:1:1 to 1:3:1. Furthermore, for Examples 1A to 3A and Comparative Examples 4A to 7A, the lengths of E1 and E2 are equal, but for Comparative Examples 1A to 3A, the lengths of E1 and E2 are different.

[0072] Therefore, if 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", meaning that the first or second left and right bottom seal portions 23A, 24B, 23B, 24A will not recede during microwave heating and the bottom will open more widely. Note that the opening width and bottom openability must be 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, steam release pouches were used that had an opening guide line such as a perforation that started from opening guide portion 70 of steam release pouch 100 shown in Fig. 1. This opening guide line started from opening guide portion 70 formed in first side seal portion 21A and was formed horizontally until it reached 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 the following Examples 1B to 3B and Comparative Examples 1B and 2B, the first sheet 11, second sheet 12, and bottom sheet 13 all had the same layer structure, and the layer configuration of each of the sheets 11 to 13, from the outermost layer, was a gas-barrier alumina-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). 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 pouches used had a maximum widthwise length of 140 mm, a steam release section 60 constituting part of the right side seal section 22 located 58 mm in height from the upper end of the outer edge of the right side seal section 22, and a height (C) of 45 mm from the fold-in section 50 of the bottom sheet 13 to the bottom end of the bottom sheet. In Examples 1B to 3B and Comparative Examples 1B and 2B, an opening guide section 70 was formed in the left side seal section 21, but the position of the opening guide section 70 differed. In Table 2, "position of opening guide section 70" refers to the height (F) from the opening guide section 70 to the bottom end of the bottom sheet 13.

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

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

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

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

[0079] <Comparative Example 2B> The steam release pouch 100 used had the 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: "opening width as viewed from the top immediately after opening after heat treatment and opening width as viewed from the top 10 minutes after opening after heat treatment," "cuttability when opening after heat treatment" (referred to as "cuttability" in Table 2), "risk of burns when removing contents 200" (referred to as "risk of burns" in Table 2), and "ease of putting containers in and taking containers out when steam release pouch 100 is used as a container after opening" (referred to as "taking containers in and out" in Table 2).

[0081] The results are shown in Table 2. The "tearability" refers to whether the first sheet 11 and the second sheet 12 were easily torn apart. In Table 2, for "tearability," 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." Furthermore, 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 "slight," 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 the steam release pouch 100 was used as a container after opening following heat treatment, if it was easy to take the container in and out, it was marked "easy," and when the steam release pouch 100 was used as a container after opening following heat treatment, if it was not easy but possible to take the container in and out, it was marked "possible."

[0082] In addition, in the "Overall Evaluation" in Table 2, it is easy to cut, there is a low risk of burns, and When the container can be easily taken out or put back in, making it easy to eat, it is marked as "◯", 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 within the range of possible to easy for putting in and taking out dishes. On the other hand, Example 1B was easy to cut, had a low risk of burns, and was within the range of possible for putting in and taking out dishes. Example 3B was easy to cut, had a slight risk of burns, and was easy to put in and take out dishes. Both Comparative Examples 1B and 2B were difficult to cut, had a high risk of burns, and were easy to put in and take out 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 section 70, which is provided between the steam release section 60 and the fold-in section 50 of the bottom sheet 13, to the upper end of the side seal section 21 in relation to the width 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 reducing the risk of burns. However, if the position of the opening guide section 70 is too high in relation to the width of the steam release pouch 100, the steam release pouch 100 will be prone to warping and will not be suitable as a container. On the other hand, the lower the position of the opening guide section 70 provided between the steam release section 60 and the fold-in section 50 of the bottom sheet 13 is relative to the width of the steam release pouch 100, i.e., the closer it is to the lower end of the side seal section 21, the more difficult it is to cut the first sheet 11 and the second sheet 12 and the more likely it is that the heat and steam from 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 section 70 is relative to the width of the steam release pouch 100, the less likely the steam release pouch 100 will bend and the more stable it will be, making it more suitable as a container. Therefore, it was confirmed that there is a trade-off between cuttability and 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. Furthermore, when a closed steam release pouch is heated in a microwave oven or the like, the steam generated from the contents increases the internal pressure, causing the containing section to expand significantly, but the steam can be released from the steam release section, preventing the steam release pouch from bursting. Furthermore, improved bottom opening also improves opening when opened after heat treatment, making it easier to remove the contents and making it easier to eat the food contents directly from the steam release pouch using the pouch as a container without transferring them to tableware. [Explanation of symbols]

[0088] 1st sheet···11 Bottom of first sheet 11A Second sheet···12 Bottom of second sheet: 12A Bottom sheet···13 Left side seal 21 The part joining the first and second sheets in the left side seal 21A Inner edge of the part joining the first and second sheets in the left side seal... 21Aa Part joining the opposing surfaces of the folded bottom sheet in the left side seal... 21B Inner edge of the part joining the opposing surfaces of the folded bottom sheet in the left side seal part...21Ba The outer edge of the part of the left side seal where the opposing surfaces of the folded bottom sheet join together... 21Bb Right side seal 22 The part joining the first and second sheets in the right side seal 22A Inner edge 22Aa of the right side seal portion where the first sheet and the second sheet are joined. Inner edge 22B of the right side seal portion where the opposing surfaces of the folded bottom sheet are joined. Inner edge of the part joining the opposing surfaces of the folded bottom sheet in the right side seal part...22Ba Outer edge of the part joining the opposing surfaces of the folded bottom sheet in the right side seal 22Bb First bottom seal part 23 First left bottom side seal part 23A Inner edge of the first left bottom side seal 23Aa First 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 the 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...24Ba Second bottom intermediate seal part···24C Inner edge of second bottom intermediate seal...24Ca Outer edge of second bottom intermediate seal 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 guide section...70 Knob 71 Steam release pouches···100 Contents...200

Claims

1. 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 being folded in a V-shape in a side view; and the pouch having a steam release section for releasing steam generated from a content, left and right side seals, a first bottom seal, and a second bottom seal are formed; the left and right side seal portions are linear and include a portion joining the first sheet and the second sheet together and a portion joining opposing surfaces of the folded bottom sheet together; the first bottom seal portion is a portion joining the first sheet and the bottom sheet, and includes first left and right bottom side seal portions, and a linear first bottom intermediate seal portion connecting 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 joining the second sheet and the bottom sheet, and includes second left and right bottom side seal portions, and a linear second bottom intermediate seal portion connecting 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 intersects with the inner edge of the first or second bottom intermediate seal portion connected to the first or second bottom side seal portion; 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 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 to the width direction length (B) of the inner edge of the first or second bottom intermediate seal portion to the length of A2 is 1:2:1 to 1:3:1; The width direction length (E1) of the left side seal portion is equal to the width direction length (E2) of the right side seal portion, 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, the ratio of the length from the lower end of the bottom sheet to the position of the opening guide portion to the width direction length of the steam release pouch is 72 / 140 to 90 / 140; A steam release pouch characterized by:

2. The relationship between the length of A1, the length of B, the length of A2, the height direction length (C) from the folded portion of the bottom sheet to the lower end of the bottom sheet, and the height direction length (D) of the linear first or second bottom intermediate seal portion is: (A1+B+A2)×2≧(CD)×3.14×2 2. The steam release pouch according to claim 1, wherein

3. The relationship between the length of C and the height direction length (F) from the opening guide portion to the lower end of the bottom sheet is C×2≦F 3. The steam release pouch according to claim 2, wherein

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