JP2019151394A - Multi-layer packaging bag - Google Patents

Abstract

To obtain a packaging bag in which the innermost layer of the packaging bag is a layer in which a content is difficult to penetrate and the high fusion strength is maintained.SOLUTION: An inner bag (2) composed of at least an inner layer (24) composed of a low-adsorption sealant, an outer layer (25) composed of a strong fusible sealant, and a multi-packaging bag (1) composed of an outer bag (3) composed of a strong fusible sealant as an inner layer (34) comprising: a multi-packaging bag characterized in that the outer and inner sides of the inner bag fusion end surface are covered with the outer bag fusion part at the inner bag peripheral edge fusion part.SELECTED DRAWING: Figure 1

Description

  The present invention mainly relates to a packaging bag having a large size of 1 liter or more and high protection performance against contents.

In order to produce an inexpensive and large packaging bag using a film, it is necessary not only to use a film having high tensile strength but also to be a packaging bag having high fusion strength.
In particular, in the case of a large packaging bag, there are many cases where long-term storage is required, and in that case, barrier properties are also an essential function.
In order to increase the strength, when manufacturing a thick packaging bag, the winding diameter becomes large even with a short length. For this reason, it is more efficient to produce a thick film at a time, rather than sequentially laminating, with less division of the film. For this reason, large packaging bags have been manufactured using coextruded laminated films.

For example, in Patent Document 1,
In a packaging bag for a bag-in-box comprising a multi-layered body in which an exterior material and at least one interior material are stacked, heat-sealing the outer end portion, and further including a spout, the exterior material is A first layer composed of an olefin resin and a barrier resin composed of an ethylene-vinyl copolymer or MXD nylon as a main resin, and further comprising a resin composition comprising an olefin resin, a rubber-like resin and a compatibilizer. A packaging bag for a bag-in-box is proposed, which is formed by laminating a second layer and a third layer made of an olefin resin by a coextrusion film forming method.

However, the bag-in-box packaging bag as described above is a film laminated by coextrusion and uses a third layer made of a normal olefin resin as an inner layer.
Although this olefin resin has a high fusion property, there is a problem that the contents are easily adsorbed and the adsorbed contents penetrate into the layer.
In particular, the above bag-in-box packaging bag includes a resin composition containing an olefinic resin, a rubbery resin and a compatibilizer in the second layer, and absorbs oily substances and low molecular weight polymers contained in the contents. Easy to penetrate.
For this reason, if the contents are stored for a long period of time, the fusion strength between the fused inner layers is remarkably reduced, and further, the deterioration inside each layer also progresses. There has been a problem that pressure is applied to the packaging bag, which causes peeling of the fused portion and breakage of the bag.

JP 2008-150095 A

  Accordingly, an object of the present invention is to obtain a packaging bag in which the innermost layer of the packaging bag is a layer in which the contents are difficult to penetrate and the high fusion strength is maintained.

The invention according to claim 1 of the present invention is
An inner bag comprising at least an inner layer comprising a low-adsorption sealant, and an outer layer comprising a strong fusible sealant;
A multi-packaging bag comprising an outer bag having a strong fusible sealant as an inner layer,
In the fusion part of the inner bag periphery, the outer and inner sides of the inner bag fusion end face are covered with the fusion part of the outer bag.

  The packaging bag of the present invention covers the fusion part of the inner bag whose adsorptivity to the contents is reduced by the low adsorption sealant with the fusion part of the strong fusible sealant of the outer bag, and has high fusion strength, and A multiple packaging bag with high storage performance can be obtained.

It is the cross-sectional view which shows 1st Embodiment of the multiple packaging bag which concerns on this invention, and sectional drawing which shows the film structure. It is the front view which shows 2nd Embodiment of the multiple packaging bag which concerns on this invention, and its cross-sectional view. It is a figure which shows the form example of the Example and comparative example which changed the seal position and sealed on the periphery of a multi-packaging bag.

Hereinafter, the multiple packaging bag of the present invention will be described with reference to the drawings.
1-1 is a cross-sectional view showing a first embodiment of a multiple packaging bag 1 according to the present invention.
The first embodiment is composed of an inner bag 2 and an outer bag 3, and the inner bag 2 and the outer bag 3 are fused together so that the peripheral edge of the inner bag 2 and the peripheral edge of the outer bag 3 are overlapped.

1-2 is an enlarged cross-sectional view showing a state in which the peripheral edges of the inner bag 2 and the outer bag 3 are fused at the peripheral edge of the multiple packaging bag 1. The outer side and inner side of the end face are covered with the outer bag peripheral edge fusion part 31.
That is, there is a double fusion part 41 in which the fusion part 21 on the peripheral edge of the inner bag and the fusion part 31 of the outer bag are fused.
In the double fused portion 41, the inner sealant layers of the front film 22 and the rear film 23 of the inner bag 2 are fused, and the front film 32 of the outer bag 3 and the front film 22 of the inner bag 2 are The rear film 33 of the outer bag 3 and the rear film 23 of the inner bag 2 are fused.
On the outer peripheral edge of the double fusion part 41, an outer peripheral edge fusion part 42 is formed, in which the front film 32 and the rear film 33 of the outer bag 3 are directly fused.
Further, the front film 32 of the outer bag 3 and the front film 22 of the inner bag 2 are fused inside the double fusion part 41, and the rear film 33 of the outer bag 3 and the rear film 23 of the inner bag 2. The inner peripheral edge fused portion 43 is formed by fusing.

FIG. 1C is a schematic cross-sectional view showing the configuration of the outer bag 3.
The outer bag 3 has an inner layer 34 composed of a strong fusion sealant layer that can be fused with the outermost layer of the inner bag 2. Usually, a high strength film such as a biaxially stretched film or a film having a high barrier property is disposed on the outside as the base material layer 35.

1-4 is a schematic cross-sectional view showing the configuration of the inner bag 2. FIG.
The inner bag 2 includes an inner layer 24 made of at least a low-adsorption sealant and an outer layer 25 made of a strong fusible sealant.

FIG. 2 is a cross-sectional view showing a second embodiment of the multiple packaging bag 1 according to the present invention.
FIG. 2-1 is an external view, and is a front view in which the film is folded in two to form one side and the other peripheral edge is fused.
As in the first embodiment, the peripheral fused portion formed of the inner bag 2 and the outer bag 3 and formed in a U-shape overlaps the peripheral edge of the inner bag 2 and the peripheral edge of the outer bag 3. It is fused in the state.
At this time, as shown in the enlarged view, the fusion part 21 at the inner bag periphery is narrower than the fusion part 31 of the outer bag, and the range of the fusion part 21 at the inner bag periphery is the same as that of the outer bag. A double fusion part 41 is formed by overlapping with the fusion part 31 and fusing.
On the outer peripheral edge of the double fusion part 41, an outer peripheral edge fusion part 42 is formed, in which the front film 32 and the rear film 33 of the outer bag 3 are directly fused.
Further, the front film 32 of the outer bag 3 and the front film 22 of the inner bag 2 are fused inside the double fusion part 41, and the rear film 33 of the outer bag 3 and the rear film 23 of the inner bag 2. The inner peripheral edge fused portion 43 is formed by fusing.

FIG. 2-2 is a cross-sectional view in which one side is bent and the other end is formed by a peripheral fusion part.
This is because the front film and the rear film are integrated and folded in half, and the peripheral fusion part is the same as in the first embodiment, the double fusion part 41 and the outer peripheral fusion part. It is formed of a wearing part 42 and an inner peripheral edge fused part 43.

The low adsorptive sealant of the inner layer 24 is a layer formed of a resin that hardly adsorbs the contents, and a biaxially stretched polyethylene terephthalate film is particularly preferable.
In addition to polyethylene terephthalate resin, polyacrylonitrile resin, cyclic polyolefin resin, ethylene / vinyl alcohol copolymer (saponified ethylene / vinyl acetate copolymer), and the like can be used.
Such a low-adsorption sealant hardly adsorbs the contents and is hardly affected by the contents, but has a very low heat sealability.
For this reason, the surface of the low-adsorption sealant film is irradiated with laser light on the peripheral surface of the packaging bag to be fused. You can also
The heat-sealable low-adsorption sealant can strongly fuse only the heat-sealable part.
Of course, a film that has been heat-sealed with a varnish coating agent may be bonded as it is.

As the laser light applied to the surface of the low adsorption sealant film, a gas laser such as a carbon dioxide laser or a nitrogen laser, or a solid laser such as a ruby laser or a YAG laser can be used.
For example, in the case of a carbon dioxide gas laser, scanning and remelting is performed so as to fill by irradiating light with a wavelength of 10.6 μm with a power of 20 to 50 watts at a speed of 500 to 5000 mm / sec at a constant narrow interval. By this, in a short time, the film melts locally and the crystal on the film surface with uniform molecular orientation breaks down and can be fused at a low melting point.

The strongly fusible sealant used for the outer layer 25 of the inner bag 2 and the inner layer 34 of the outer bag 3 is low density polyethylene resin, linear low density polyethylene resin, medium density polyethylene resin, high density polyethylene resin, ethylene propylene. It is formed from either a copolymer, a polypropylene resin, or the above mixture.
Since it does not come into contact with the contents, a resin with high fusing property can be used.

A film having high tensile strength and high tear resistance is used for the outer layer 35 of the outer bag 3.
Of course, a high barrier property can be used.
In order to increase the tensile strength, puncture resistance, tear resistance, and surface hardness, a highly crystalline resin can be produced by biaxial stretching.
In addition, it is possible to improve the barrier property by depositing a metal oxide such as silicon oxide on the film, or to improve the low temperature drop resistance and the bending resistance by laminating a polyamide film. .
Of course, in order to increase flexibility, a film in which a strong-melting sealant such as polyolefin resin is further laminated on the front surface side of the outer layer may be used.

<Configuration example 1>
As a laminated film for outer bags of multiple packaging bags,
From the outside, a film in which low-density polyethylene 40 μm, 6-nylon (polyamide) 15 μm, and low-density polyethylene 60 μm were laminated in this order was used.
Moreover, as a laminated film for inner bags,
A film in which 60 μm of low density polyethylene and 12 μm of polyethylene terephthalate were laminated in this order from the outside, and the inner surface was irradiated with laser light was used. The laser beam is irradiated with a carbon dioxide laser with a wavelength of 10.6 μm at an output of 30 watts, the irradiation range is a spot diameter of 0.14 mm, the scanning speed is 4000 mm / sec, and the scanning interval is 0.15 mm. The surface of the area was scanned and processed.

<Configuration example 2>
As a laminated film for outer bags of multiple packaging bags,
From the outside, a film in which low-density polyethylene 40 μm, 6-nylon (polyamide) 15 μm, and low-density polyethylene 60 μm were laminated in this order was used.
Moreover, as a laminated film for inner bags,
A film in which 60 μm of low-density polyethylene and 12 μm of polyethylene terephthalate deposited with silicon oxide were laminated in this order from the outside, and a laser beam was applied to the inner surface in the same manner as in Configuration Example 1 was used.

<Configuration example 3>
As a laminated film for outer bags of multiple packaging bags,
From the outside, a film in which low-density polyethylene 40 μm, 6-nylon (polyamide) 15 μm, and low-density polyethylene 60 μm were laminated in this order was used.
Moreover, as a laminated film for inner bags,
A film in which low-density polyethylene 60 μm, polyethylene terephthalate 12 μm, and cyclic polyolefin 30 μm were laminated in this order from the outside was used.

<Configuration example 4>
As a laminated film for outer bags of multiple packaging bags,
From the outside, a film in which low-density polyethylene 40 μm, 6-nylon (polyamide) 15 μm, and low-density polyethylene 60 μm were laminated in this order was used.
Moreover, as a laminated film for inner bags,
From the outside, a film in which 60 μm of low-density polyethylene, 12 μm of polyethylene terephthalate deposited with silicon oxide on the outside, and 30 μm of cyclic polyolefin were laminated in this order.

<Configuration example 5>
As a laminated film for outer bags of multiple packaging bags,
From the outside, a film in which low-density polyethylene 40 μm, 6-nylon (polyamide) 15 μm, and low-density polyethylene 60 μm were laminated in this order was used.
Moreover, as a laminated film for inner bags,
A film in which low-density polyethylene 60 μm, polyethylene terephthalate 12 μm, and heat-sealable-ethylene / vinyl alcohol copolymer (ethylene / vinyl acetate copolymer saponified product) 35 μm were laminated in this order from the outside.

<Configuration example 6>
As a laminated film for outer bags of multiple packaging bags,
From the outside, a film in which low-density polyethylene 40 μm, 6-nylon (polyamide) 15 μm, and low-density polyethylene 60 μm were laminated in this order was used.
Moreover, as a laminated film for inner bags,
A film in which low-density polyethylene 60 μm, polyethylene terephthalate 12 μm with silicon oxide deposited on the outside, and polyacrylonitrile 25 μm were laminated in this order from the outside.

<Configuration example 7>
As a laminated film for outer bags of multiple packaging bags,
From the outside, a film in which low-density polyethylene 40 μm, 6-nylon (polyamide) 15 μm, and low-density polyethylene 60 μm were laminated in this order was used.
Moreover, as a laminated film for inner bags,
A film in which low-density polyethylene 60 μm, polyethylene terephthalate 12 m, and heat-sealable-polyethylene terephthalate 35 μm were laminated in this order from the outside.

<Configuration example 8>
As a laminated film for outer bags of multiple packaging bags,
From the outside, a film in which low-density polyethylene 40 μm, polybutylene terephthalate 15 and low-density polyethylene 60 μm were laminated in this order was used.
Moreover, as a laminated film for inner bags,
A film in which 60 μm of low density polyethylene and 12 μm of polyethylene terephthalate were laminated in this order from the outside and the inner surface was irradiated with laser light in the same manner as in Structural Example 1 was used.

<Configuration example 9>
A low-density polyethylene 80 μm film was used as a film for the outer bag of the multi-packaging bag. Moreover, as a laminated film for inner bags,
A film in which 60 μm of low-density polyethylene and 12 μm of polyethylene terephthalate deposited with silicon oxide were laminated in this order from the outside, and a laser beam was applied to the inner surface in the same manner as in Configuration Example 1 was used.

<Configuration example 10>
As a laminated film for outer bags of multiple packaging bags,
A film in which 40 μm of low density polyethylene, 15 μm of polybutylene terephthalate, and 60 μm of low density polyethylene were laminated in this order was used.
Moreover, as a laminated film for inner bags,
A film in which 60 μm of low-density polyethylene and 12 μm of polyethylene terephthalate deposited with silicon oxide were laminated in this order from the outside, and a laser beam was applied to the inner surface in the same manner as in Configuration Example 1 was used.

<Configuration Example 11>
As a laminated film for outer bags of multiple packaging bags,
A film in which 40 μm of low density polyethylene, 15 μm of 6-nylon (polyamide), 15 μm of 6-nylon (polyamide) and 60 μm of low density polyethylene were laminated in this order was used.
Moreover, as a laminated film for inner bags,
A film in which 60 μm of low-density polyethylene and 12 μm of polyethylene terephthalate deposited with silicon oxide were laminated in this order from the outside, and a laser beam was applied to the inner surface in the same manner as in Configuration Example 1 was used.

<Configuration example 12>
As a laminated film for outer bags of multiple packaging bags,
A film in which polyethylene terephthalate 12 μm, 6-nylon (polyamide) 15 μm, and low-density polyethylene 60 μm were laminated in this order was used from the outside.
Moreover, as a laminated film for inner bags,
A film in which 60 μm of low-density polyethylene and 12 μm of polyethylene terephthalate deposited with silicon oxide were laminated in this order from the outside, and a laser beam was applied to the inner surface in the same manner as in Configuration Example 1 was used.

<Configuration Example 13>
As a laminated film for outer bags of multiple packaging bags,
A film in which polyethylene terephthalate having a silicon oxide vapor deposition on the outside, 12 μm, 6-nylon (polyamide) 15 μm, and low-density polyethylene 60 μm were laminated in this order from the outside.
Moreover, as a laminated film for inner bags,
A film in which 60 μm of low-density polyethylene and 12 μm of polyethylene terephthalate deposited with silicon oxide were laminated in this order from the outside, and a laser beam was applied to the inner surface in the same manner as in Configuration Example 1 was used.

<Configuration Example 14>
As a laminated film for outer bags of multiple packaging bags,
A film in which polyethylene terephthalate 12 μm and low-density polyethylene 60 μm were laminated in this order was used from the outside.
Moreover, as a laminated film for inner bags,
A film in which 60 μm of low-density polyethylene and 12 μm of polyethylene terephthalate deposited with silicon oxide were laminated in this order from the outside, and a laser beam was applied to the inner surface in the same manner as in Configuration Example 1 was used.

<Configuration Example 15>
As a laminated film for outer bags of multiple packaging bags,
A film in which 6-nylon (polyamide) 15 μm and low-density polyethylene 60 μm were laminated in this order was used from the outside.
Moreover, as a laminated film for inner bags,
A film in which 60 μm of low-density polyethylene and 12 μm of polyethylene terephthalate deposited with silicon oxide were laminated in this order from the outside, and a laser beam was applied to the inner surface in the same manner as in Configuration Example 1 was used.

In the above configuration example, a sample of the positional relationship between the inner bag 2 and the outer bag 3 based on the embodiment shown in FIG.
That is, FIG. 3-2 is the sealing position of the embodiment, and the outer bag peripheral edge fusion portion 31 is located on the outer side and inner side of the inner bag fusion end surface with respect to the inner bag peripheral edge fusion portion 21. 31.
On the other hand, FIG. 3-3 is a sealing position of the comparative example A type, and the outer bag peripheral edge fused portion 31 covers only the outer side of the inner bag peripheral edge fused portion 21 end surface, and does not cover the inner end surface.
3-4 is a seal position of the comparative example B type, and the outer bag peripheral edge fusion part 31 covers only the inner side of the inner bag peripheral edge fusion part 21 end surface, and does not cover the outer end face.
Further, FIG. 3-5 is a comparative example C type, which is an example of an inner bag only and no outer bag.

That is, Example 1 uses the film configuration of Configuration Example 1, the periphery is the sealing position of FIG. 3-2, and the outer bag peripheral fusion portion 31 is fused to the inner bag peripheral fusion portion 21. The embodiment was carried out in an embodiment in which the outer side and the inner side of the end face are covered with the outer bag peripheral edge fusion part 31.
Similarly, Example 2 uses the film configuration of Configuration Example 2, and the periphery is the sealing position of FIG. 3-2. Example 3 uses the film configuration of Configuration Example 3, and the periphery is the sealing position of FIG. 3-2.
Example 4 uses the film configuration of Configuration Example 4, and the periphery is the sealing position of FIG. 3-2.
Example 5 uses the film configuration of Configuration Example 5, and the periphery is the sealing position of FIG. 3-2.
Example 6 uses the film configuration of Configuration Example 6, and the periphery is the sealing position of FIG. 3-2.
Example 7 uses the film configuration of Configuration Example 7, and the periphery is the sealing position of FIG. 3-2.
Example 8 uses the film configuration of Configuration Example 8, and the periphery is the sealing position of FIG. 3-2.
Example 9 uses the film configuration of Configuration Example 9, and the periphery is the sealing position of FIG. 3-2.
Example 10 uses the film configuration of Configuration Example 10, and the periphery is the sealing position of FIG. 3-2.
Example 11 uses the film configuration of Configuration Example 11, and the periphery is the sealing position of FIG. 3-2.
Example 12 uses the film configuration of Configuration Example 12, and the periphery is the sealing position of FIG. 3-2.
Example 13 uses the film configuration of Configuration Example 13 and the periphery is the sealing position of FIG. 3-2.
Example 14 uses the film configuration of Configuration Example 14, and the periphery is the sealing position of FIG. 3-2.
Example 15 uses the film configuration of Configuration Example 15, and the periphery is the sealing position of FIG. 3-2.

Comparative Example 1 uses the film configuration of Configuration Example 1, the periphery is the sealing position of FIG. 3-3, the inner bag fusion end surface inner side position and the outer bag peripheral edge fusion end surface inner side are the same position, and the inner bag periphery The outer bag peripheral edge fusion part 31 was implemented with respect to the fusion part 21 in the embodiment in which only the outer side of the inner bag fusion end surface is covered with the outer bag peripheral edge fusion part 31.
Similarly, Comparative Example 2 uses the film configuration of Configuration Example 2, and the periphery is the sealing position of FIG. Comparative Example 3 uses the film configuration of Configuration Example 3, and the periphery is the sealing position of FIG.
Comparative Example 4 uses the film configuration of Configuration Example 4, and the periphery is the sealing position of FIG.
Comparative Example 5 uses the film configuration of Configuration Example 5, and the periphery is the sealing position of FIG.
Comparative Example 13 uses the film configuration of Configuration Example 13, and the periphery is the sealing position of FIG.

Comparative Example 6 uses the film configuration of Configuration Example 6, the peripheral edge is the sealing position of FIG. 3-4, the inner bag fusion end face outer side position and the outer bag peripheral edge fusion end face outer side are the same position, and the inner bag peripheral edge The outer bag peripheral edge fusion part 31 was implemented with respect to the melt | fusion part 21 in the example which covered only the inner side of the inner bag fusion end surface with the outer bag peripheral edge fusion part 31. FIG.
Similarly, Comparative Example 6 uses the film configuration of Configuration Example 6, and the periphery is the sealing position of FIGS. 3-4. The comparative example 7 uses the film structure of the structural example 7, and a periphery is a sealing position of FIGS. 3-4.
The comparative example 8 uses the film structure of the structural example 8, and a periphery is a sealing position of FIGS. 3-4.
The comparative example 9 uses the film structure of the structural example 9, and a periphery is a sealing position of FIGS. 3-4.
Comparative Example 14 uses the film configuration of Configuration Example 14, and the peripheral edge is the sealing position of FIG. 3-4.

In Comparative Example 10, the film configuration of Configuration Example 10 was used, and as shown in FIGS. 3-5, the embodiment was composed of a packaging bag having only an inner bag without an outer bag.
Similarly, Comparative Example 11 uses the film configuration of Configuration Example 11 and is an embodiment in which only the inner bag is used.
The comparative example 12 uses the film structure of the structural example 12, and is an embodiment example with only an inner bag.
Comparative Example 15 is an embodiment in which the film configuration of Configuration Example 15 is used and only the inner bag is used.

<Adsorbability evaluation method>
The contents for confirming the adsorptivity were tomato ketchup. (Please correct the name of the actual contents used.)
As a film for the inner bag, fold the film of 290 mm long and 390 mm wide vertically and seal the U-shaped periphery,
As an outer bag film, a 300 mm long and 400 mm wide film was folded in half and the U-shaped periphery was sealed to obtain a double packaging bag in the state of FIG.
At this time, 1 kg of the contents of tomato ketchup is put before sealing on one side, sealed, put into an environmental test machine at 40 ° C. and 90% relative humidity for 200 hours, and then left at room temperature for 24 hours before opening. Then, it was confirmed that the contents were not adsorbed on the inner surface of the packaging bag.

<Drop resistance evaluation method>
The contents for confirming the drop resistance were water, and three types of packaging bags of 1 liter, 6 liters and 20 liters were prepared. (Please correct the name of the actual contents used.)
The packaging bag for 1 liter, as a film for the inner bag, folds the film of length 290mm, width 390mm vertically, and seals the U-shaped periphery,
As an outer bag film, a 300 mm long and 400 mm wide film was folded in half and the U-shaped periphery was sealed to obtain a double packaging bag in the state of FIG.
At this time, before sealing one side, put 1 liter of water of the contents, seal it, leave it in an environmental tester with 20 ° C and 40% relative humidity for 24 hours, and flatten it with concrete from a height of 1m It was dropped and checked for the presence of broken bags.

The 6-liter packaging bag is a film for an inner bag, which is a 550 mm long and 640 mm wide film folded in half and sealed in a U-shaped periphery,
As an outer bag film, a film having a length of 565 mm and a width of 655 mm was folded in two vertically, and the U-shaped periphery was sealed to obtain a double packaging bag in the state shown in FIG.
At this time, before the sealing of one side, put 6 liters of water of the contents, seal it, leave it in an environmental test machine of 20 ° C and 40% relative humidity for 24 hours, and flatten it with concrete from a height of 1 m It was dropped and checked for the presence of broken bags.

The packaging bag for 20 liters, as a film for the inner bag, folds the film of length 740mm, width 1080mm vertically and seals the U-shaped periphery,
As an outer bag film, a film having a length of 760 mm and a width of 1100 mm was folded in half, and the U-shaped periphery was sealed to obtain a double packaging bag in the state shown in FIG.
At this time, before sealing one side, put 20 liters of water in the contents, seal it, leave it in an environmental test machine at 20 ° C. and 40% relative humidity for 24 hours, and flatten it with concrete from a height of 1 m. It was dropped and checked for the presence of broken bags.

<Adsorption evaluation results>
In all of the examples and comparative examples, no matter that adsorbed and colored or deteriorated occurred.

<Drop resistance evaluation result>
In Examples 1 to 15, there was no bag breakage in 1 liter, 6 liters and 20 liters.
In Comparative Example 1 to Comparative Example 5 and Comparative Example 13, there was a problem that the edge was cut off at the inner end face of the seal portion and the contents leaked out when 1 liter was dropped.
In Comparative Example 6 to Comparative Example 9 and Comparative Example 14, there was a problem that, when 1 liter was dropped, the fused portion between the inner bags was peeled off to break the bag, and the contents were scattered.
In Comparative Example 10 to Comparative Example 12 and Comparative Example 14, there was a problem that the film itself broke and the contents were scattered in the case of dropping by 1 liter.

Based on the above results, drop impact resistance is improved by forming a multiplexed packaging bag and covering the outer and inner sides of the inner bag fusion end surface with the outer bag fusion portion at the fusion portion around the inner bag. It was confirmed that
Furthermore, the adsorption by the contents can be prevented by the low adsorption sealant, and the effect of heat sealability partially provided by the laser beam has been confirmed.
According to the present invention, drop resistance can be obtained simply by multiplexing and devising the end face of the fused portion, so that a high effect can be obtained without requiring new equipment for mass production. Of course, it is possible to provide a spout plug and the like to improve the usability and to take the form of a gusset that increases the capacity of the film, and the merit of the present invention is great.

1 ... Packing bag 2 ... Inner bag 21 ... Inner bag peripheral fusion part 22 ... Front film (inner bag)
23 ..... Rear film (inner bag)
24 ..... Inner layer (inner bag)
25 ... Outer layer (inner bag)
3 ... Outer bag 31 ... Outer bag peripheral fusion part 32 ... Front film (outer bag)
33 .... Rear film (outer bag)
34 ........ Inner layer (outer bag)
35 .... Base material layer (outer bag)
41... Double fused portion 42... Outer peripheral edge fused portion 43...

Claims (4)

An inner bag comprising at least an inner layer comprising a low-adsorption sealant, and an outer layer comprising a strong fusible sealant;
A multi-packaging bag comprising an outer bag having a strong fusible sealant as an inner layer,
A multi-packaging bag characterized in that the outer and inner sides of the inner bag fusion end face are covered with the outer bag fusion portion in the fusion portion of the inner bag periphery.   The multiple packaging according to claim 1, wherein the low-adsorption sealant is composed of any one of heat-sealable polyethylene terephthalate resin, polyacrylonitrile resin, heat-sealable ethylene-vinyl alcohol copolymer, and cyclic polyolefin resin. bag.   The multi-packaging bag according to claim 1, wherein the low-adsorption sealant comprises a heat-sealable film obtained by irradiating a polyethylene terephthalate film or a vinyl alcohol copolymer film with laser light to impart a fusion property.   The strongly fusible sealant is made of any one of a low density polyethylene resin, a linear low density polyethylene resin, a medium density polyethylene resin, a high density polyethylene resin, an ethylene / propylene copolymer, a polypropylene resin, or a mixture thereof. The multiple packaging bag according to any one of claims 1 to 3.

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