JP7698175B2 - packaging bag - Google Patents

Description

The present invention relates to a packaging bag for use in a microwave oven.

There are known packaging bags filled with contents such as retort food, which can be heated in a microwave oven or the like while standing upright. For example, the packaging bag in Patent Document 1 has excellent self-standing stability, making it effective for displaying in stores.

JP 2005-306426 A

On the other hand, when the contents are liquid, they need to be transferred to another container after opening, which can cause the contents to spill.

The present invention was made in consideration of these circumstances, and the object of the present invention is to provide a packaging bag that allows easy handling of liquid materials contained therein.

The present invention provides a packaging bag for use in a microwave oven, in which a flexible film is formed into a bag shape and which has a spout attached.

With this configuration, the user can pour out the contents through the spout attached to the packaging bag, eliminating the risk of spilling when transferring the contents to another container. Also, because the spout is attached to the packaging bag, it is possible to seal the bag with some of the contents poured out. In this way, it becomes possible to easily handle the liquid contained inside.

Various embodiments of the present invention will be described below. The embodiments described below can be combined with each other.
Preferably, the container has a peripheral portion having a front portion and a back portion opposed to each other, and the peripheral portion is provided with a steam release seal portion which forms a steam flow path as the internal pressure increases.
Preferably, the steam release seal portion is formed at a position spaced from the center in the left-right direction of the packaging bag in a plan view.
Preferably, the steam release seal portion is provided on the opposite side to the spout with respect to the center in the left-right direction of the packaging bag in a plan view.
Preferably, the packaging bag is configured to be self-supporting.

FIG. 1 is a perspective view of a packaging bag 1 according to a first embodiment of the present invention. FIG. 2 is a diagram showing a packaging bag 1 in a plan view. A perspective view of the bottom film 20a that constitutes the bottom portion 2. Fig. 4A is a side view of the peripheral wall film 20b, and Fig. 4B is a diagram showing a state in which a part of the peripheral wall film 20b has been cut and the bottom film 20a has been inserted into the cut portion. 1A and 1B are diagrams showing how the packaging bag 1 is manufactured by welding the peripheral wall film 20b and the bottom film 20a. FIG. 11 is a plan view showing a packaging bag 1 according to a second embodiment. FIG. 11 is a perspective view of a packaging bag 1 according to a third embodiment. FIG. 11 is a plan view showing a packaging bag 1 according to a third embodiment. FIG. 13 is a perspective view of a packaging bag 1 according to a fourth embodiment.

The following describes the embodiments of the present invention. The various features shown in the following embodiments can be combined with each other. In addition, each feature can be an invention independently.

1. First embodiment As shown in Figures 1 and 2, a packaging bag 1 in an embodiment of the present invention is a self-supporting packaging bag for a microwave oven in which a flexible film is formed into a bag shape. The packaging bag 1 has a bottom portion 2 and a peripheral portion 21 provided to rise from the bottom portion 2. The peripheral portion 21 has a front portion 3 and a back portion 4 opposed to each other. The front portion 3 and the back portion 4 are welded to each other at their left and right ends (hereinafter also referred to as side ends). The bottom portion 2 is welded (heat sealed) to the front portion 3 and the back portion 4. In this way, the bottom portion 2, the front portion 3, and the back portion 4 are welded to each other, and the film is formed into a bag shape.

In this disclosure, the top, bottom, left and right of FIG. 2 will be described as the top, bottom, left and right of the packaging bag 1. Specifically, the bottom portion 2 side will be the lower side, and the front portion 3 (and back portion 4) side will be the upper side. In addition, the left and right sides when the front portion 3 is placed in front will be the left and right sides of the packaging bag 1. Furthermore, the front portion 3 side will be the front side, and the back portion 4 side will be the rear side.

The front surface 3 has a lower front surface 3a and an upper front surface 3b. The lower front surface 3a is welded to the bottom surface 2. The lower front surface 3a and the upper front surface 3b are folded over each other and welded to each other at a joint portion 10 formed by overlapping the inner surfaces of the lower front surface 3a and the upper front surface 3b.

Figure 2 is a diagram showing the packaging bag 1 in a plan view. A plan view means a view perpendicular to the front surface 3 of the packaging bag 1 when no contents are contained in the packaging bag 1.

A side end weld 12 is provided at the side end of the packaging bag 1, welding the front portion 3 and the back portion 4 together. This fixes the front portion 3 and the back portion 4 in the front-to-rear direction. Furthermore, a bottom end weld 13 is provided at the bottom end of the packaging bag 1, welding the bottom portion 2 to the front portion 3, and the bottom portion 2 to the back portion 4. Furthermore, an top end weld 22 is provided at the top end of the packaging bag 1, welding the front portion 3 to the back portion 4 together.

The lower end welded portion 13 is the area below the center line E (see Figure 3) of the bottom film 20a, and welds the bottom portion 2 to the front portion 3, and the bottom portion 2 to the back portion 4 at the side and bottom ends of the packaging bag 1.

A side end inclined portion 14 is formed on one of the left and right sides of the upper end welded portion 22, continuing from the upper end to the side end of the packaging bag 1. A spout (pouring spout) 25 is attached to the side end inclined portion 14. More specifically, the spout 25 has a pouring outlet 25a and a base 25b, and the front portion 3 and the back portion 4 are welded together so as to sandwich the base 25b.

The packaging bag 1 is formed with a steam release seal portion 11. The steam release seal portion 11 is provided at the joint portion 10. The steam release seal portion 11 is a welded portion having a lower weld strength than other welded portions. When the internal pressure of the packaging bag 1 increases due to steam generated inside the packaging bag 1 by heating the packaging bag 1, a steam flow path is formed in the steam release seal portion 11. The steam inside the packaging bag 1 is discharged to the outside through the steam release seal portion 11.

The steam release seal portion 11 is formed at a position spaced apart from the center in the left-right direction of the packaging bag 1 in a plan view. More preferably, the steam release seal portion 11 is provided on the opposite side of the spout 25 in the left-right direction of the packaging bag 1, with the center in the left-right direction of the packaging bag 1 as a reference. This makes it possible to prevent the contents from leaking from the steam release seal portion 11 when the contents are poured out from the spout 25.

The vertical length H1 of the packaging bag 1 is preferably 10 to 17 cm, more specifically, any of the values 10, 11, 12, 13, 14, 15, 16, and 17 (unit: cm), and may also be within a range between any two of the values exemplified here, for example, 14 cm.

The length H2 from the top of the packaging bag 1 to the bottom end of the base 25b of the spout 25 is preferably H2/H1≧0.15, where H1 is the vertical length of the packaging bag 1. More preferably, 0.3≧H2/H1≧0.15, and more specifically, the value of H2/H1 is any one of 0.15, 0.20, 0.25, and 0.30, and may also be within a range between any two of the numerical values exemplified here.

The length L1 of the packaging bag 1 in the left-right direction is preferably 8 to 15 cm, more specifically, any one of the values 8, 9, 10, 11, 12, 13, 14, or 15 (unit: cm), and may be within a range between any two of the values exemplified here, for example, 10 cm.

It is desirable that the length L2 from the end closest to the center in the left-right direction of the base 25b of the spout 25 to the end closest to the packaging bag 1 satisfies L2/L1≧0.15 with respect to the left-right length L1 of the packaging bag 1. It is preferable that 0.3≧H2/H1≧0.15, and more specifically, the value of L2/L1 is any one of 0.15, 0.20, 0.25, and 0.30, and may also be within a range between any two of the numerical values exemplified here.

It is desirable that the length L3 from the center of the steam release seal portion 11 to the near end of the packaging bag 1 satisfies L3/L1≦0.2 with respect to the left-right length L1 of the packaging bag 1. It is preferable that 0.1≦L3/L1≦0.2, and more specifically, the value of L3/L1 is any one of 0.10, 0.15, and 0.20, and may also be within a range between any two of the numerical values exemplified here.

As shown in Figures 3 to 5, the packaging bag 1 is manufactured by inserting a bottom film 20a, which is folded into a V shape at the center line E, between the front portion 3 and the back portion 4. Here, the length H3 from the center line E to the bottom end of the bottom film 20a is preferably 3 to 6 cm, and more specifically, is any value of 3, 3.5, 4, 4.5, 5, 5.5, or 6 (unit: cm), or may be within a range between any two of the numerical values exemplified here, for example, 4.5 cm. A notch R is formed on both ends of the bottom film 20a.

The length r1 from the center line E of the bottom film 20a to the center of the notch R is preferably 1 to 3 cm, and more specifically, is any of the values 1, 1.5, 2, 2.5, or 3 (unit: cm), and may also be within a range between any two of the values exemplified here, for example, 2.5 cm.

The diameter of the notch R is preferably 1 to 4 cm, more specifically, any of the values 1, 1.5, 2, 2.5, 3, 3.5, or 4 (unit: cm), and may also be within a range between any two of the values exemplified here, for example, 2 cm.

The manufacturing procedure for the packaging bag 1 is briefly explained below with reference to Figures 4 and 5.

First, as shown in FIG. 4A, the inner surfaces of the ends of one peripheral wall film 20b are overlapped to form an overlapping portion 10a, and as shown in FIG. 4B, the overlapping portion 10a is welded to form a joint portion 10, and the remaining portion forms an elliptical ring C.

Next, as shown in Figures 4A to 4B, one end C1 of the ring C is cut and a bottom film 20a folded into a V shape is inserted. Next, as shown in Figures 4B to 5, the bottom film 20a and the peripheral wall film 20b are welded together and the other end C2 of the ring C is cut off to form the bottom portion 2, front portion 3, and back portion 4. After that, a part of the upper side of the front portion 3 and back portion 4 is cut away to form the side end inclined portion 14, and the spout 25 is inserted and welded to produce the packaging bag 1.

The bottom film 20a and the peripheral wall film 20b are preferably laminated films having a base layer and a sealant layer, and it is even more preferable to have an adhesive layer and a printing layer between the base layer and the sealant layer.

The base layer is arranged so as to be exposed on the outer surface of the packaging bag 1, and the sealant layer is arranged so as to be exposed on the inner surface of the packaging bag 1. The sealant layers are welded (heat sealed) together to form a welded portion.

The substrate layer is formed from a material that has excellent strength and high impact resistance. For example, polyamide, polyolefin, polyethylene, polyester, etc. can be used as the substrate layer. More specifically, stretched polyethylene terephthalate film, silica-deposited stretched polyethylene terephthalate film, alumina-deposited stretched polyethylene terephthalate film, stretched nylon film, stretched polypropylene film, polypropylene/ethylene-vinyl alcohol copolymer co-extruded co-stretched film, etc. can be used. As the film that constitutes the substrate layer, one that has linear cutability in the MD direction (the direction in which the film flows during production) is preferable.

The adhesive layer is a layer for bonding the base layer and the sealant layer together. The bonding method may be, for example, extrusion lamination using polyethylene or the like as an adhesive layer, or dry lamination using a polyvinyl acetate adhesive, a polyacrylic ester adhesive, a cyanoacrylate adhesive, an ethylene copolymer adhesive, a cellulose adhesive, a polyester adhesive, a polyamide adhesive, an amino resin adhesive, an epoxy adhesive, a polyurethane adhesive, or the like as an adhesive.

The sealant layer can be formed from a resin with excellent weldability. The sealant layer can be formed from a polyolefin resin such as polyethylene, polypropylene, ethylene-vinyl acetate copolymer, or ethylene-propylene block copolymer, and more specifically, unstretched polypropylene or linear low-density polyethylene can be used. The film that constitutes the sealant layer is preferably one that has linear cut properties in the MD direction.

An intermediate layer may be provided between the base layer and the sealant layer. The intermediate layer may be a film of polyethylene terephthalate, polyamide, polyethylene, polypropylene or other polyolefin, polyvinyl chloride, polycarbonate, polyvinyl alcohol, ethylene-propylene copolymer, saponified ethylene-vinyl acetate copolymer, or the like, or a film of these coated with polyvinylidene chloride, or a film of silicon oxide, aluminum oxide, or other inorganic material vapor-deposited thereon, or a film of polyvinylidene chloride, or the like.

It is preferable that the bottom film 20a has a tensile modulus that decreases with increasing temperature. In this case, when the packaging bag 1 is heated, the film softens and the lower end of the central part of the packaging bag 1 is likely to open in the front-to-rear direction. Here, the tensile modulus of the film constituting the bottom part 2 in the TD direction (corresponding to the front-to-rear direction of the packaging bag 1) at 23.5°C and 100°C are M1 and M2, respectively. The tensile modulus can be determined by conducting a tensile test in accordance with JIS K 7127. The tensile test speed is 50 mm/min, and the dumbbell shape used for the test is No. 5.

M1 is preferably 600 to 1400 MPa, and more preferably 800 to 1200 MPa. Specific examples of M1 are 600, 700, 800, 900, 1000, 1100, 1200, 1300, and 1400 MPa, and may be within a range between any two of the numerical values exemplified here.

M2 is preferably 200 to 600 MPa, and more preferably 300 to 500 MPa. Specifically, M2 may be, for example, 200, 250, 300, 350, 400, 450, 500, 550, or 600 MPa, or may be within a range between any two of the numerical values exemplified here.

The value of M1/M2 is, for example, 1.2 to 4, and preferably 1.5 to 3. Specific examples of this value are 1.2, 1.5, 2, 2.5, 3, 3.5, and 4, and may be within a range between any two of the numerical values exemplified here.

The peripheral film 20b may have the same physical properties as the bottom film 20a, or may have different physical properties. The sealant layers of the bottom film 20a and the peripheral film 20b are preferably made of the same resin, and the sealant layer is preferably formed thicker than the base layer. More specifically, the ratio D1/D2 of the thickness D1 of the sealant layer to the thickness D2 of the base layer is preferably 1≦D1/D2≦2. That is, the ratio D1/D2 may be any of 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, and 2.0, or may be within a range between any two of the values exemplified here. In this way, by making the sealant layer of the bottom film 20a thicker than the base layer, the self-supporting stability is improved.

2. Second embodiment A second embodiment of the present invention will be described with reference to Fig. 6. This embodiment differs from the above embodiment in that the gable portion 10 including the steam release seal portion 11 is provided at a position corresponding to the side end inclined portion 14 in the up-down direction. The following description will focus on the differences.

In the packaging bag 1 of this embodiment, as shown in FIG. 6, the gable portion 10 having the steam release seal portion 11 is provided at a position equivalent to the side end inclined portion 14 in the vertical direction (more specifically, at a position equivalent to the base 25b of the spout 25). With this configuration, the steam release seal portion 11 can be provided at the top of the packaging bag 1, which not only allows more contents to be accommodated in the packaging bag 1, but also makes it less likely for the contents to leak from the steam release seal portion 11 when pouring them out. Even with this configuration, the present invention can achieve the same effects as the above embodiment.

7 and 8, a third embodiment of the present invention will be described. This embodiment differs from the above-described embodiment in that a gripping portion 24 for a user to grip the packaging bag 1 is provided on one of the left and right ends of the packaging bag 1. The following description will focus on the difference.

As shown in Figs. 7 and 8, in the packaging bag 1 of this embodiment, a gripping portion 24 is provided on the outside of the side end welded portion 12 on the opposite side of the spout 25 in the left-right direction. The gripping portion 24 includes a front gripping portion 24a and a back gripping portion 24b. As shown in Fig. 8, the front gripping portion 24a and the back gripping portion 24b are welded to each other at their upper ends and side ends, and are welded to the bottom portion 2 at their lower ends.

The gripping portion 24 can be rolled up on the front or back side of the packaging bag 1. By gripping the rolled up gripping portion 24, the packaging bag 1 can be easily gripped even immediately after heating. The rolled up gripping portion 24 may be fixed to the front portion 3 or back portion 4 with tape or the like. Even in such a configuration, the present invention can achieve the same effects as the above embodiment.

4. Fourth embodiment A fourth embodiment of the present invention will be described with reference to Fig. 9. In this embodiment, the packaging bag 1 is a so-called gusset type having a side portion 5 between a front portion 3 and a back portion 4, which is different from the above-mentioned embodiments. The following description will focus on the differences.

As shown in FIG. 9, in the packaging bag 1 of this embodiment, the front portion 3 and the back portion 4 are welded to a pair of side portions 5, respectively, to form a substantially rectangular peripheral portion 21. The spout 25 is attached to the left-right center of the upper end welded portion 22. Here, it is preferable to provide the steam release seal portion 11 at a position spaced apart from the left-right center. Even in this form, the present invention can achieve the same effects as the above embodiment.

5. Other Embodiments Although the embodiments have been described above, the technical ideas of the present disclosure can also be adopted in the following aspects.
In the above embodiment, the fixing portion 15 is configured as a semicircular notch R formed in the bottom portion 2, but the present invention is not limited to this. For example, the opposing surfaces of the bottom film may be bonded together using an adhesive, or the front portion 3 and the rear portion 4 may be fixed in the front-rear direction by a fastening means such as a stapler.
In the above embodiment, the bottom portion 2 is made of a film folded into a V shape, but this is not limited to this form and may be made of a film folded into a W shape, for example.
The packaging bag 1 does not have to have the steam release seal portion 11. In that case, for example, the upper end of the bag (preferably the side opposite the spout 25 in the left-right direction) may be opened slightly to release the steam generated during heating.
The packaging bag 1 does not have to have the seam portion 10.
The steam release seal portion 11 may be provided in a portion other than the joint portion 10 .
The method for manufacturing the packaging bag 1 is not limited to the method described in the above embodiment.
The shape of the packaging bag 1 is not limited to the above embodiment. For example, the packaging bag may be a flat bag shape that is not free-standing and needs to be laid down when heated. However, in the case of a free-standing packaging bag as in the above embodiment, it is possible to leave the bag as it is after pouring out a part of the contents, which makes it easier to handle.

1: Packaging bag 2: Bottom surface portion 3: Front surface portion 3a: Lower front surface portion 3b: Upper front surface portion 4: Rear surface portion 5: Side surface portion 10: Joint portion 10a: Joint portion 11: Steam release seal portion 12: Side end welded portion 13: Lower end welded portion 14: Side end inclined portion 15: Fixing portion 20a: Bottom film 20b: Peripheral wall film 21: Peripheral surface portion 22: Upper end welded portion 24: Grip portion 24a: Front grip portion 24b: Rear grip portion 25: Spout 25a: Pouring outlet 25b: Base portion

Claims (3)

A packaging bag for a microwave oven, in which a flexible film is formed into a bag shape,
a peripheral portion having opposing front and rear portions;
A side end inclined portion is formed extending from the upper end to the side end of the packaging bag,
A spout is attached to the side end inclined portion,
the front portion comprises a lower front portion and an upper front portion;
The front lower portion and the front upper portion are folded back on each other and welded to each other at a joint portion formed by overlapping inner surfaces of the front lower portion and the front upper portion,
The joint portion is provided with a steam release seal portion that forms a steam flow path as the internal pressure increases,
The steam release seal portion is provided on the opposite side of the spout in the left-right direction of the packaging bag, with the left-right center of the packaging bag as a reference, in a plan view. A packaging bag for a microwave oven, in which a flexible film is formed into a bag shape,
a peripheral portion having opposing front and rear portions;
A side end inclined portion is formed extending from the upper end to the side end of the packaging bag,
A spout is attached to the side end inclined portion,
the front portion comprises a lower front portion and an upper front portion;
The front lower portion and the front upper portion are folded back on each other and welded to each other at a joint portion formed by overlapping inner surfaces of the front lower portion and the front upper portion,
The joint portion is provided with a steam release seal portion that forms a steam flow path as the internal pressure increases,
The packaging bag includes a side end welding portion where the front portion and the back portion are welded together at a side end of a portion that contains the contents to be poured out through the spout,
A packaging bag, wherein a grip portion for a user to grip the packaging bag is provided on an outer side of the side end welded portion opposite the spout in the left-right direction of the packaging bag. The packaging bag according to claim 1 or 2,
The packaging bag is configured to be self-supporting.