JP4562880B2 - Microwave packaging bag - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a packaging bag for a microwave oven that can heat the contents while being packaged and can automatically release the internal pressure.
[0002]
[Prior art]
When heating food that is sealed and packaged in a package, etc. using a microwave oven, if it remains in a sealed system, the internal pressure in the system rises due to steam generated by heating, and the packaging bag eventually ruptures, It is well known that the contents are scattered in the microwave oven. Various methods are known for preventing such rupture of bags and the like. For example, there is a method of cutting a part of the packaging bag with scissors before heating the microwave oven, or heating after making a hole in the packaging bag with a sharp tip (feature flat 10-72070). Further, a non-woven fabric is provided on a part of the bag so that the vapor can escape (Japanese Patent Laid-Open No. 9-240754), or a weak seal portion or a notch is provided (Japanese Patent Laid-Open No. 9-142541, 10-95471). is there.
[0003]
[Problems to be solved by the invention]
However, these methods have the following problems. For example, it is troublesome to cut with scissors or make holes before heating. Moreover, in the method using a nonwoven fabric for a part of a bag, it does not become a hermetically sealed state but causes freeze-drying in frozen foods. Moreover, a special apparatus and process are required for production of a packaging bag, and a cost becomes high.
An object of the present invention is to provide a packaging bag for a microwave oven that can heat the contents while being packaged and can automatically release the internal pressure.
[0004]
[Means for Solving the Problems]
In the present invention, when a package body filled with contents is heated in a microwave oven, an arc-shaped or trapezoidal opening is formed toward the upper part of the package by steam generated, and the opening is formed from the opening. A packaging bag for a microwave oven for use in a packaging body in which steam is not dissipated and unbroken, using a composite film composed of at least one surface of a heat seal layer, a lower member having a heat seal surface as an upper surface, and heat seal In the microwave packaging bag formed by forming a wing portion with the surfaces sealed, overlapping an upper member with the heat seal surface as the lower surface, and heat-sealing the peripheral portion, the vapor is transferred to the microwave packaging bag. In order to automatically open the opening that diffuses outside, the wing portion is provided with an easy-to-vaporize means selected from at least one notch, an unsealed portion, a slit, or a hole, Between both the heat seal layer of Ingu portion is interposed easy peel film, seal strength of the wing portion is weaker than the seal strength of the other seal portion, and wherein the composite film is viewed contains a biaxially oriented film, and A microwave oven packaging bag, wherein a ratio of a distance from one end of the microwave packaging bag to the wing and a distance from the wing to the other end is ½ or less. Oh Ru.
[0005]
DETAILED DESCRIPTION OF THE INVENTION
The present invention relates to a packaging bag that can be heated by a microwave oven in a state where the contents are sealed, and has one surface (an upper surface when left in a microwave oven when heated in a microwave oven) of two films. A wing portion is formed from the wing portion, and an easy peel film is interposed in the wing portion and heat sealed. Hereinafter, it will be described in detail with reference to the drawings.
FIG. 1: is the perspective view which isolate | separated and showed the (a) perspective view and (b) each member which show the Example of the packaging bag for microwave ovens of this invention. FIG. 2 is a cross-sectional view of part X ₁ -X ₁ . FIG. 3 is a partial perspective view for explaining various easy-to-steam units. FIG. 4 is a diagram illustrating a state in which a microwave packaging bag is heated and automatically opened, taking as an example a notch type as an easy steaming means, (a) an initial stage of peeling of the wing part, (b) opening (C) is a cross section of X ₂ -X ₂ part, and (d) is a cross section of X ₃ -X ₃ part.
FIG. 5 is a perspective view showing the position of the wing part. FIG. 6 is a cross-sectional view in the case where the contents are filled in the microwave packaging bag of the present invention and heated by the microwave oven, and shows a state in which steam is diffused by (a) before heating and (b) heating.
[0006]
The microwave packaging bag 1 according to the present invention is, for example, a four-side seal type bag as shown in FIG. 1 (a) or FIG. 1 (b), and has a wing portion formed on one side thereof. . And as shown to Fig.2 (a), it consists of three members, the lower member 2, the upper member 3a, the upper member 3b, and an easy peelable film. The upper members 3a and 3b have their heat seal surfaces facing each other, an easy peelable film is inserted between them and heat sealed to form a wing portion, and a lower member and a wing portion are formed. It can be set as the packaging bag for microwave ovens by facing sealant layers and heat-sealing a peripheral blend.
Each member of the packaging bag has at least a heat-resistant base material layer 11, 21, 31 and a sealant layer 12, 22, 32 as shown in FIG. 2 (b), FIG. 2 (c), and FIG. 2 (d). It is formed from a laminate.
[0007]
The easy peel film may be a single layer or multiple layers, but a single film (a laminated film is not good because the adhesive or anchor agent touches the contents) and can be thermally bonded to the synthetic resin film, and the sealing strength is other than that. It will not specifically limit if it becomes smaller than the intensity | strength of a seal part. Further, the easy peel film may be inserted into the entire wing portion or partially.
[0008]
The seal strength at the part where the easy peel film is interposed is 3 to 50 N / 15 mm at 23 ° C., preferably 5 to 30 and 15 N / 15 mm or less at 90 ° C., preferably 715 N / 15 mm or less. In the present invention, the easy peel film R to be inserted when the wing portion 4 is heat-sealed is selected according to the material of the sealant layer of the lower member 2 and the upper member 3, specifically A film made of a polymer alloy of polypropylene and polystyrene, a blend resin of polypropylene and polyethylene, a polypropylene multilayer resin, an ethylene-vinyl acetate copolymer film, or the like.
[0009]
The easy peelable film R interposed in the wing part 4 makes it easy to form an opening by protruding at least 1 mm inside the packaging bag.
Thereafter, the lower member 2 and the upper member 3 are overlapped, and the filling side when filling the contents is not sealed, and the peripheral edge portion is heat-sealed to form the packaging bag 1 for the microwave oven of the present invention. Can do.
[0010]
When the contents F are stored in the microwave packaging bag 1 of the present invention formed as described above, and the high-frequency heating is performed by the microwave, the easy peel film R and the sealant layer are softened by the heat of the steam generated by the heating. Then, as shown in FIGS. 4A and 4C, the easy peelable film portion interposed in the wing portion and any heat seal surface of the upper member are peeled off first, and heating is continued. As a result, as shown in FIGS. 4B and 4D, the opening 8 is formed, and the vapor Vp filled in the packaging bag and brought into a pressurized state is diffused out of the packaging bag.
[0011]
Furthermore, the present inventor provides various easy-to-steam means 6 described below in the wing portion 4 formed in the microwave packaging bag 1 of the present invention, so that the automatic opening during heating by the microwave oven is stabilized. I found out that it would be done. Specifically, the evaporating means 6 is provided with at least one notch, an unsealed portion, a slit, a hole and the like so as to be hung on the portion where the easy peel film R of the wing portion is inserted. is there.
The evaporating means 6 provided in the wing part 4 has a distance m of 3 to 8 mm from the lowermost end to the lowermost seal part of the wing part. If the distance m from the lowermost end of the easy-evaporating means 6 to the lowermost seal part of the wing is less than 3 mm, the strength is weak and there is a risk of breaking the bag into the flow resin. When the distance m from the lower end to the lowermost end of the seal portion of the wing portion exceeds 8 mm, it is difficult for steam to escape and bag breakage from other seal blends may occur.
[0012]
When the microwave oven packaging bag of the present invention is filled with the contents and heated by the microwave oven in a sealed state, as shown in FIG. 4 (a), the lower end of the seal of the wing portion has a lower seal strength than the other seal portions. Peeling starts from the point, and the shape of the peeled portion 7 progresses to an arc or trapezoid. When the tip of the peeling reaches the lower end of the easy-evaporation means 6 (the illustrated easy-evaporation means is a notch type), an opening 8 is formed. The size and shape of the opening 8 are determined by the material of the sealant layer, the type of easy vaporization means, the separation area between the heat-resistant base material layer and the sealant layer, the height of the internal pressure, and the like. Since the vapor Vp is diffused out of the bag from the opening 8 formed in this way, there is an effect that an explosive opening can be avoided.
[0013]
As shown in FIGS. 6A and 6B, the wing part 4 of the microwave packaging bag of the present invention is positioned above the stationary packaging bag when heated by the microwave oven. Since the opening 8 of the packaging bag by heating is formed in the upper portion, there is no risk of the contents F spilling, and even if the contents F are mixed with liquid or liquid components, the opening The portion 8 does not spill out of the packaging bag.
[0014]
Next, each member which forms the packaging bag 1 for microwave ovens of this invention is demonstrated. Each of the members may be formed of only a sealant layer, but as shown in FIGS. 2B, 2C, and 2D, respectively, in terms of strength, heat resistance, content protection, and the like. It is preferable to use laminates 10, 20, and 30 in which heat-resistant base material layers 11, 21, and 31 and sealant layers 12, 22, and 32 are laminated.
Here, the heat-resistant substrate layer may be a single layer or a multilayer (lamination), and is not particularly limited as long as it is generally used as a food packaging material heated or cooked in a microwave oven.
For example, as the heat-resistant substrate layers 11, 21, and 31 in the microwave packaging bag of the present invention, a stretched polyethylene terephthalate film, a silica-deposited stretched polyethylene terephthalate film, an alumina-deposited stretched polyethylene terephthalate film, a stretched nylon film, and a silica-deposited stretch Nylon film, alumina-deposited stretched nylon film, stretched polypropylene film, polyvinyl alcohol coated stretched polypropylene film, nylon 6 / metaxylenediamine nylon 6 co-pressed co-stretched film or polypropylene / ethylene-vinyl alcohol copolymer co-pressed co-stretched film, and these Can be used.
[0015]
The resin forming the sealant layers 12, 22, 32 in the upper member 3 and the lower member 2 constituting the packaging bag for a microwave oven of the present invention is generally used as a packaging material for food that is heated or cooked in a microwave oven. If it is a thing, it will not specifically limit.
For example, low density polyethylene, ultra low density polyethylene, linear low density polyethylene, medium density polyethylene, high density polyethylene, unstretched polypropylene, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ethylene-methacrylic acid copolymer Any resin such as a polymer, an ethylene-methyl acrylate copolymer, or an ionomer can be used. The thickness of the sealant layer is 20 to 100 μm, preferably 40 to 70 μm.
[0016]
The lamination of the base material layer and the sealant layer is not particularly limited as long as it is a conventionally known method such as coextrusion or dry lamination.
[0017]
As shown in FIG. 5, the position of the wing portion in the microwave packaging bag of the present invention is unevenly distributed from the end side of the packaging bag, and the distance from the wing portion to the end portion is any It is desirable that the distance is ½ or less of the other distance.
When the distance is 1/2 or more, preferable automatic opening cannot be performed in heating by a microwave oven.
Specifically, in the packaging bag illustrated in FIG. 5, a ≦ 1 / 2b
It is desirable to provide a wing part within the range.
[0018]
When the package body with the structure and material described above filled and sealed with the contents is heated by a microwave oven, as shown in FIG. 4 (a), the wings are generated by the heat and pressure of the steam generated by the heating. Peeling starts from the lower end of the heat seal part of the part, and if peeled, it spreads in an arc shape or a trapezoidal shape toward the upper part and reaches the lower end part of the easy-permeability means provided in the wing part. And an opening part is formed, as shown in FIG.6 (b), a vapor | steam dissipates from an opening part, a packaging bag internal pressure returns to a normal pressure, and it does not become explosive bag breaking of a packaging bag. And if it puts and heats in a microwave oven with a wing part up, since the opening part will be formed in the upper part of a packaging bag, even if the contents were a liquid, there was no fear of spilling.
[0019]
【Example】
The microwave oven packaging bag of the present invention will be described in more detail with reference to examples.
[Example 1]
Using a packaging method in which a stretched nylon film having a thickness of 15 μm and a linear low-density polyethylene having a thickness of 60 μm were dry-laminated, a pouch (150 × 200 mm) as shown in FIG. As a result of putting a frozen hamburger (220 g) into this packaging bag and heating it with a 500 W microwave oven, steam was gently released from the slit provided in the wing part after about 3 minutes and 30 seconds. There was no spilling out of the contents as it came out of the top of the pouch.
[Example 2]
A pouch (140 × 180 mm) as shown in FIG. 1 was prepared using a packaging material obtained by dry laminating a 12 μm thick alumina-deposited polyethylene terephthalate film, a 15 μm stretched nylon film, and a 60 μm unstretched polypropylene film. After curling (200g) in this packaging bag and retorting, it was heated in a 500W microwave oven. As a result, the steam was gently removed from the slit provided in the wing after about 1 minute and 40 seconds. It was.
[0020]
【The invention's effect】
As a packaging bag for a microwave oven, the end portions of the two upper members are respectively opposed to the heat seal surface, heat sealed with an easy peel film interposed therebetween, provided with a wing portion, and heat sealed at the periphery, Even if the resulting bag is filled with the contents to form a packaging bag, and the packaging bag is heated in a microwave oven in a sealed state, the package can be heated sufficiently without explosive breaking. Since the opening is formed in the upper part of the packaging bag, there is no risk of spilling of the contents, and it is an excellent method that can be directly heated by a microwave oven.
[Brief description of the drawings]
1A is a perspective view showing an embodiment of a packaging bag for a microwave oven according to the present invention, and FIG.
FIG. 2 is a cross-sectional view of part X ₁ -X ₁ .
FIG. 3 is a partial perspective view for explaining various easily steaming means.
FIGS. 4A and 4B are diagrams for explaining a state in which a microwave packaging bag is heated and automatically opened, taking as an example a notch type as an easy-to-vaporize means, (a) initial stage of wing part peeling, (b) opening (C) is a cross section of X ₂ -X ₂ part, and (d) is a cross section of X ₃ -X ₃ part.
FIG. 5 is a perspective view showing a position of a wing part.
FIGS. 6A and 6B are cross-sectional views in the case where the contents are filled in the microwave packaging bag of the present invention and heated by the microwave oven, and show a state in which steam is diffused by (a) before heating and (b) heating.
[Explanation of symbols]
F Contents Vp Vapor R Easy peel film 1 Microwave packaging bag 2 Lower member 3 Upper member 4 Wing part 5 Peripheral seal part 6 Evaporating means 7 Peeling part 8 Opening part 10 Laminated body 11 constituting the lower member Base material layer 12 Sealant layer 20 Laminate 21 constituting upper member A Heat resistant base layer 22 Sealant layer 30 Laminate 31 constituting upper member B Heat resistant base layer 32 Sealant layer

Claims (1)

When the package body filled with the contents is heated in a microwave oven, the generated steam forms an arc-shaped or trapezoidal opening toward the top of the package, and the steam is diffused from the opening. A packaging bag for a microwave oven that is used for a package that does not break the bag, and uses a composite film composed of at least one side of a heat seal layer, and seals the lower member with the heat seal surface as the upper surface and the heat seal surfaces In the microwave packaging bag formed by overlapping the upper member with the heat sealing surface as the lower surface and heat-sealing the peripheral edge, the vapor is diffused out of the microwave packaging bag. In order to automatically open the opening, at least one notch, an unsealed part, a slit or a hole is provided in the wing part, and the wing part is provided. By interposing a easy peel film between both the heat seal layer, the seal strength of the wing portion is weaker than the seal strength of the other seal portion, and wherein the composite film is viewed contains a biaxially oriented film, and the electron A packaging bag for a microwave oven, wherein a ratio of a distance from one end portion of the packaging bag for a range to the wing portion and a distance from the wing portion to the other end is ½ or less .

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