Package for heat treatment

Abstract

To provide a package for heat treatment which prevents an opening shape of a bag from becoming distorted when filled with contents, making it easy to be filled with the contents, and enables a seal of a sealing portion provided with a steam vent portion to be easily peeled off by steam pressure.SOLUTION: A package 1 for heat treatment of the present invention includes a standing-type bag in which a sheet base material is folded twice, at least a bottom side 5 and both side sides 3 are sealed in advance, and an upper edge portion 6 that closes an upper opening after contents are placed inside is sealed at a predetermined width, in which a guide seal portion 4 is formed on an inside of at least one of the side edges 3, connecting to the upper edge portion 6 and extending downward, and an inner edge 10 of the guide seal portion 4 has an upper linear portion 10x extending linearly from the upper edge portion 6, and a dimension from an upper end to a lower end of the inner edge 10 that contacts the upper edge portion 6 is longer than 1 / 6 but less than 1 / 2 of a shortest distance dimension from the lower end of the upper edge portion 6 to an uppermost position of the bottom edge portion, and a steam vent portion 7 is formed at a bottom of the guide seal portion 4.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a package for heat treatment. [Background technology]

[0002] A known heat treatment package for cooking in a microwave oven is one in which a plastic film is folded twice and sealed at the periphery, and which has a steam vent that releases pressure when the internal pressure of the package increases due to heating (see Patent Document 1).

[0003] The package described in Patent Document 1 has a steam release section that protrudes inward from the side seal of the bag body. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 4459763 Summary of the Invention [Problem to be solved by the invention]

[0005] In a package such as that described in Patent Document 1, the steam vent protrudes from the side seal of the bag toward the inside, which causes a problem in that when the bag is opened to fill the contents, the shape of the opening becomes distorted, which can lead to filling problems. On the other hand, the inventor discovered that depending on the position of the side seal, the side seal around the steam release section may not peel off properly when the inside of the bag is pressurized, making it impossible to release steam properly. Therefore, the present invention provides a package for heat treatment that prevents the opening shape of the bag from becoming distorted when the contents are filled, making it easier to fill the contents, and that allows the seal of the sealed part, which has a steam vent part, to be easily peeled off by steam pressure. [Means for solving the problem]

[0006] The heat treatment package of the present invention comprises a standing-type bag body in which a sheet base material is folded twice, at least the bottom and both side edges are pre-sealed, and the top edge portion that closes the top opening after the contents are placed inside is sealed, and a guide seal portion is formed on the inside of at least one of the both side edges, connecting to the top edge portion and extending downward, and the inner edge of the guide seal portion has an upper straight portion that extends linearly from the top edge portion, and the vertical dimension from the upper end to the lower end of the inner edge that contacts the top edge portion is at least 1 / 6 but less than 1 / 2 of the dimension of the shortest distance from the lower end of the top edge portion to the uppermost position of the bottom edge portion, and a steam vent portion that penetrates through the thickness of the sheet base material is formed at the bottom of the guide seal portion. With this configuration, the opening of the bag body is less likely to become distorted, and it is possible to avoid a situation in which the guide seal portion is not peeled off due to steam pressure.

[0007] The inner edge of the heat treatment package of the present invention may have a recess below the upper straight section that is recessed toward one of the side edges, and a lower straight section below this recess and on an extension of the upper straight section, and the steam vent section may be formed in the area where the lower straight section is formed. With this configuration, steam pressure is also likely to be applied to the recess above the steam vent portion, and peeling of the seal of the guide seal portion is more likely to reach the steam vent portion inside the guide seal portion.

[0008] The entire guide seal portion, including the outside of the opening edge of the steam vent portion of the package for heat treatment of the present invention, may be sealed. When forming a non-sealed portion in the guide seal portion and then forming a steam vent portion in the non-sealed portion, alignment with the non-sealed portion is required. However, with the configuration of the present invention, fine alignment is not required when forming the steam vent portion in the guide seal portion, and manufacturing defects can be reduced.

[0009] The steam release portion of the heat treatment package of the present invention may be a small hole and / or a slit, and the small hole and / or the slit may be formed in the range of the lower third of the guide seal portion in the vertical direction. With this configuration, the steam pressure inside the bag can be efficiently applied to the periphery of the steam release portion formed in the guide seal portion. [Effects of the Invention]

[0010] The heat treatment packaging of the present invention prevents the opening shape of the bag from becoming distorted when the contents are filled, making it easier to fill the contents properly, and also has the effect of allowing the seal of the sealed portion provided with a steam vent portion to be properly peeled off by steam pressure. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a perspective view showing a package for heat treatment according to one embodiment of the present invention. [Figure 2] 1 is a cross-sectional view showing the configuration of a sheet material used in a bag body of the present invention. [Figure 3] FIG. 10 is a perspective view showing a package for heat treatment according to another embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Note that the dimensions of each part in the drawings used in the following description are not necessarily the same as the actual dimensions and can be changed as appropriate.

[0013] As shown in FIG. 1, a package for heat treatment 1 according to one embodiment of the present invention has a bag body 2 made by doubly folding a single sheet body with the bottom gusseted and sealing the periphery.

[0014] The bag body 2 is sealed by heat sealing at both side edges 3, 3, a guide seal portion 4, and a bottom edge portion 5 that forms a gusset. An upper edge portion 6 of the bag body 2 is unsealed before filling with the contents and is sealed after filling. In addition, a steam release portion 7 is formed in the guide seal portion 4. The shape of the bag body 2 is not particularly limited, but in this embodiment it is formed to be rectangular when viewed from the front.

[0015] The side edges 3, 3 are strip-shaped portions of a predetermined width that are sealed from the side edges 2b of the double-folded sheet body. The width of both side portions 3,3 (ie, the horizontal dimension from the side edge 2b of the sheet body) is not limited, but is typically set to about 5 mm to 10 mm, depending on the desired seal strength. The seal strength of both side portions 3, 3 is set to 23 N / 15 mm or more, and in this embodiment, 40 N / 15 mm or more. The seal strength of both side portions 3, 3 is not particularly limited, but is generally set to about 150 N / 15 mm or less.

[0016] The space between the upper ends of both side portions 3, 3, as indicated by the boundary of imaginary line L in FIG. 1, is an upper side portion 6 that is sealed after the contents such as food are filled. The width of the top side portion 6 (that is, the dimension in a direction perpendicular to the longitudinal direction of the top side portion 6 extending horizontally) can be set to be approximately the same as the width of the side side portion 3. The seal strength of the top edge portion 6 is the same as that of the side edge portion 3, and is set to 23 N / 15 mm or more, 40 N / 15 mm in this embodiment. The upper side portion 6 may be formed at a position lower than the upper edge 2 a of the bag body 2 .

[0017] The guide seal portion 4 is a seal portion that contacts the inside of the side edge portions 3, 3 and extends downward from the upper edge 2a of the bag body 2. The width of the guide seal portion 4 is equal to or greater than the width of the both side portions 3, 3. The specific width dimension of the guide seal portion 4 is appropriately set based on the shape and dimensions of the steam vent portion 7 and the dimension set from the end of the steam vent portion 7 to the inner edge of the guide seal portion 4, which determines the storage area for the contents.

[0018] The inner edge of the guide seal portion 4 (i.e., the portion other than the outer edge (shown by a dotted line in Figure 1) that is in contact with the side edge portion 3) has an inner edge 10 that extends in a straight line with its upper end 10a as the point of contact with the lower edge 6c of the upper edge portion 6, and a lower edge 11 that extends approximately horizontally from the lower end 10b of the inner edge 10 toward the side edge portion 3.

[0019] The intersection of the inner edge 10 and the lower edge 11 of the guide seal portion 4 forms a corner K of a predetermined angle. As long as the corner K is formed, the angle may be acute or obtuse, but is preferably in the range of 60° to 120°, and more preferably in the range of 60° to 100°. A sharper angle of the corner K makes it easier for the seal of the guide seal portion 4 to peel off due to steam pressure.

[0020] The overall length D1 of the inner edge 10 of the guide seal portion 4, which extends downward (i.e., downward in the vertical direction when the bag body 2 is upright; the same applies below) from the lower edge 6c of the upper edge portion 6, which is sealed after the contents are filled, is set to be greater than or equal to one-sixth and less than one-half of the shortest distance D2 from the lower edge 6c of the upper edge portion 6 to the top T of the gusset of the bottom edge portion 5.

[0021] If the overall length D1 of the inner edge 10 is less than one-sixth of the length D2, when the upper edge portion 6 of the bag body 2 is sealed and heated, the steam pressure acting on the corner portion K may be insufficient, and the steam release portion 7 may not open.

[0022] If the overall length D1 of the inner edge 10 of the guide seal portion 4 is greater than half the length D2, the filling efficiency of the contents will be extremely poor, since the contents must be filled up to a position lower than the height position of the steam release portion 7.

[0023] The seal strength of the guide seal portion 4 is the same as the seal strength of the both side portions 3, 3, and is set to 23 N / 15 mm or more, 40 N / 15 mm in this embodiment.

[0024] In the bag body 2, the inside of both side portions 3, 3 and the area below the lower end edge 11 of the guide seal portion 4 form a storage portion S for the contents. A steam release portion 7 is formed below the guide seal portion 4. Specifically, the steam release portion 7 is formed in the range of the lower one-third of the guide seal portion 4 in the vertical direction, i.e., in the range from the lower edge of the guide seal portion 4 to one-third of the entire length in the vertical direction of the guide seal portion 4. It is more preferable that the steam release portion 7 is formed in the range of the lower one-quarter of the guide seal portion 4 in the vertical direction, i.e., in the range from the lower edge of the guide seal portion 4 to one-quarter of the entire length in the vertical direction of the guide seal portion 4.

[0025] The steam release portion 7 is formed by small holes and / or slits that penetrate the double-layered sheet body in the thickness direction. The size of the small holes is determined depending on the steam pressure to be applied inside the bag body 2, but is typically set to about 1 mm to 8 mm.

[0026] The steam release portion 7 is formed by punching in the sealed portion, without being formed in an unsealed portion that can be formed in the guide seal portion 4. In other words, the outside of the opening edge is sealed in the same way as the other portions, with no unsealed portion being formed around the steam release portion 7. The small holes can be suitably formed by punching with a circular blade.

[0027] The bottom side portion 5 comprises a lower side portion 15 extending horizontally, a gusset forming portion 16 extending from both ends of the lower side portion 15 along the gusset of the gusset toward the top T of the gusset, and an inclined side portion 17 extending obliquely from the top T of the gusset forming portion 16 relative to the lower side portion 15 and forming a boat-shaped bottom when the bag body 2 becomes three-dimensional.

[0028] The top T of the gusset forming portion 16 is continuous with the lower end of the side portion 3 . The sealing strength of the bottom side portion 5 is set to 23 N / 15 mm or more, similar to the sealing strength of the both side portions 3, 3.

[0029] A multilayer resin film having at least an inner layer film and an outer layer film is used for the bag body 2 used in the heat treatment package 1. In this embodiment, as shown in Fig. 2, an intermediate layer film 23 is interposed between the inner layer film 21 and the outer layer film 22.

[0030] The resin used for the thermal adhesive resin layer of the inner layer film 21 can be any resin commonly used for food packaging materials heated or cooked in a microwave oven. Specific examples include low-density polyethylene film, ultra-low-density polyethylene film, linear low-density polyethylene film, medium-density polyethylene film, high-density polyethylene film, unstretched polypropylene film, ethylene-vinyl acetate copolymer film, ethylene-acrylic acid copolymer film, ethylene-methacrylic acid copolymer film, ethylene-methyl acrylate copolymer film, ethylene-ethyl acrylate copolymer film, ethylene-methyl methacrylate copolymer film, and ionomer film. The thickness of the sealant layer is 20 to 100 μm, preferably 40 to 70 μm.

[0031] A synthetic resin having excellent mechanical, physical, chemical, etc. properties is used as the outer layer film 22 used as the outer layer of the bag body 2. Specifically, the film used as the outer layer of the bag body 2 may be made of, for example, a polyester-based, polyamide-based, polypropylene-based, polycarbonate-based, polyacetal-based resin, or may be cellophane, synthetic paper, or the like.

[0032] Furthermore, since printing is generally performed on the inner layer side of the outer layer film 22, printability is required, and a biaxially stretched film is suitable. The thickness of the outer layer film 22 may be sufficient to maintain the minimum necessary strength, rigidity, etc., of the basic material, and, taking cost into consideration, a thickness of approximately 12 to 30 μm is preferable. Furthermore, the outer layer film 22 may be configured to have barrier properties as needed, such as a film coated with polyvinylidene chloride or a film formed with a vapor-deposited layer of an inorganic material such as silicon oxide or aluminum oxide.

[0033] The sheet material of the bag body 2 may include an intermediate layer film 23 provided between the inner layer film 21 and the outer layer film 22. The intermediate layer film 23 is typically provided when the inner layer film 21 and the outer layer film 22 alone are unable to fully fulfill the functions of a packaging bag. Such functions include gas barrier properties, mechanical toughness, bending resistance, puncture resistance, impact resistance, abrasion resistance, cold resistance, heat resistance, and chemical resistance, and these final functions required of the bag body 2 are achieved by providing the intermediate layer.

[0034] Examples of substrates that can be used as the intermediate layer film 23 include films of polyolefins such as polyethylene terephthalate, polybutylene terephthalate, polyamide, polyethylene, and polypropylene, polyvinyl chloride, polycarbonate, polyvinyl alcohol, ethylene-propylene copolymer, and saponified ethylene-vinyl acetate copolymer, as well as paper, cellophane, synthetic paper, and nonwoven fabric. One or more of these substrates can be used in combination. The thickness of the substrate can be selected appropriately as needed, as long as it satisfies the functions required of the package.

[0035] The package for heat treatment 1 having the above-described configuration does not have a structure that protrudes inward at the inner edge 10 of the guide seal portion 4. Therefore, when the bag body 2 is stood upright and the upper opening is widened, the bag body 2 is not easily hindered from opening in a consistent shape, and a distorted opening can be avoided, making it possible to create an opening shape that is as consistent as possible in the vertical direction. Therefore, the package for heat treatment 1 has the effect of making it easy to open the bag body 2 and fill it with contents smoothly.

[0036] Furthermore, because the steam release section 7 is provided in the range of the lower one-third in the vertical direction of the guide seal section 4, peeling of the guide seal section 4 can easily reach the steam release section 7. Therefore, when the interior of the package for heat treatment 1 reaches a predetermined steam pressure, the steam release section 7 can be opened quickly, which has the effect of enabling the interior of the package for heat treatment 1 to be maintained at the predetermined steam pressure as quickly as possible.

[0037] Furthermore, since the inner edge 10 of the guide seal portion 4 is formed in a straight line, there is an effect that the contents can be filled while being well guided into the bag body 2 when the contents are filled.

[0038] The guide seal portion 4 is entirely sealed except for the inside of the cut in the steam release portion 7 (i.e., the inside of the small hole and the slit itself), and does not have any unsealed portions. Therefore, the steam release portion 7 can be simply placed in a predetermined position in the guide seal portion 4, and no other positioning is required. This makes it easy to set the steam release portion 7, and has the effect of reducing the yield of the package for heat treatment 1.

[0039] As shown in FIG. 3, the guide seal portion 4 of the present invention may have a recess 25 formed below an upper straight portion 10x extending in a straight line from the lower edge 6c of the upper side portion 6, a steam vent portion 7 provided below the recess 25, and a lower straight portion 10y formed below the recess and extending in an extension of the upper straight portion 10x. According to this configuration, the steam vent section 7 is surrounded by the recess 25, the lower straight section 10y, and the lower edge 11 of the guide seal section 4, which has the effect of applying steam pressure to the recess 25 as well, making it easier to peel off the seal of the guide seal section 4.

[0040] In the above embodiment, the vapor release portion 7 is a small hole, but the vapor release portion 7 may be a slit. When the vapor release portion 7 is a slit, the slit is preferably formed in the horizontal direction.

[0041] In addition, in the above embodiment, the guide seal portion 4 and the steam vent portion 7 are formed on both the left and right sides of the bag body 2, but the guide seal portion 4 and the steam vent portion 7 may also be formed on either one of the bag body 2. [Example]

[0042] The present invention will be described in detail below using examples, but the present invention is not limited to these examples. [Example]

[0043] A heat treatment package (170 mm long x 200 mm wide) having the configuration shown in Figure 1 was produced. The multilayer film was constructed using aluminum oxide vapor-deposited polyethylene terephthalate (thickness 12 μm) as the outer layer film 22, biaxially oriented nylon (thickness 15 μm) as the intermediate layer film 23, and unstretched polypropylene (thickness 60 μm) as the inner layer film 21. The width of both side portions 3, 3, bottom portion 5, top portion 6 and guide seal portion 4 was set to 8 mm.

[0044] The length from the upper end 10a to the lower end 10b of the inner edge 10 of the guide seal portion 4 was set to 40 mm. The length from the lower edge 6c of the upper side portion 6 to the top T of the gusset of the bottom side portion 5 was set to 125 mm. The seal strength of both side portions 3, 3, bottom portion 5, top portion 6 and guide seal portion 4 was all set to 40 N / 15 mm. The steam vent portion 7 was a small hole with a diameter of 4 mm, and the distance from the inner edge 10 and the lower edge 11 of the guide seal portion 4 was 5 mm. [Example]

[0045] A package for heat treatment 1 was produced in the same manner as in Example 1, except that polybutylene terephthalate (PBT) was used as the intermediate layer 23 instead of biaxially oriented nylon (film thickness 15 μm).

[0046] 100 ml of tap water was sealed in the heat treatment package 1 prepared in Example 1 and Example 2 and subjected to heat treatment. When this heat treatment package was heated in a 600W microwave oven, the steam release section 7 opened in 1 minute 30 seconds, and the internal air was gradually released, maintaining the internal steam pressure at a nearly constant level. Furthermore, no water leaked from the heat treatment package 1. [Explanation of symbols]

[0047] 1. Heat treatment packaging 2 bags 3 Side part 4 Guide seal part 5 Bottom 6 Top 7 Steam release section 10 medial border 10x Upper straight section 10y lower straight section 11 Bottom edge

Claims

1. The bag is a standing bag body in which a sheet base material is folded twice, at least the bottom side and both side sides are sealed in advance, and the top side part that closes the top opening after the contents are placed inside is sealed, A guide seal portion is formed on the inside of at least one of the side edges, the guide seal portion being connected to the upper edge portion and extending downward; The inner edge of the guide seal portion has an upper linear portion that extends linearly from the upper side portion, the vertical dimension from the upper end to the lower end of the inner edge contacting the upper side portion is at least 1 / 6 but less than 1 / 2 of the dimension of the shortest distance from the lower end of the upper side portion to the uppermost end position of the base side portion, The package for heat treatment has a steam vent portion formed below the guide seal portion, the steam vent portion penetrating through the thickness of the sheet substrate.

2. the inner edge has a recess below the upper linear portion that is recessed toward the one side edge portion, and a lower linear portion provided below the recess on an extension of the upper linear portion, The package for heat treatment according to claim 1 , wherein the steam release portion is formed in the region where the lower linear portion is formed.

3. 3. The package for heat treatment according to claim 1, wherein the entire guide seal portion, including the outside of the opening edge of the steam vent portion, is sealed.

4. the vapor release portion is a small hole and / or a slit, 3. The package for heat treatment according to claim 1, wherein the small holes and / or slits are formed in a range of the lower third in the vertical direction of the guide seal portion.

Images