JP2866587B2 - Packaging bag - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a packaging bag formed of a film made of a synthetic resin so as to store an object in a sealed state.

[0002]

2. Description of the Related Art Such a packaging bag is used, for example, when packaging an object to be heated which can be subjected to heat treatment in a microwave oven or the like in a sealed state. By the way, in such a packaging bag,
For example, while food is stored in a sealed state in the bag interior space,
When heating and cooking in a microwave oven, there is a possibility that the internal pressure of the bag interior space increases due to steam generated from the food, the packaging bag bursts, and the food is scattered in the cooking space of the microwave oven.
Therefore, in general, in order to prevent such a rupture of the packaging bag, a hole is made in the packaging bag before cooking, so that the inside space of the bag is ventilated to the outside of the bag, and cooking by heating in a microwave oven is performed. It is encouraged that the vapors that evolve from foods at times can be released out of the bag.

[0003]

However, it is not only troublesome to take a procedure such as making a hole in the packaging bag before cooking, but if the user forgets to take such a procedure, the packaging bag may be ruptured. There was a problem that it would.

[0004] The present invention has been made in view of the above circumstances, and has as its object, when performing a heat treatment in a microwave oven or the like, the steam generated from the object to be heated without performing any special treatment in advance. It is an object of the present invention to provide a packaging bag capable of preventing a rupture due to a rise in atmospheric pressure.

[0005]

A first characteristic configuration of a packaging bag according to the present invention is that a film portion for forming an internal space facing the internal space of the bag in the film has an internal pressure increase in the internal space of the bag. A heat-sealed part is formed by partially heat-sealing the films so that a tensile force acts with the
The present invention is characterized in that a break opening can be made at or near the periphery of the heat-sealed portion by the tensile force due to the internal pressure. A second characteristic configuration is that the heat-sealed portion is formed by partially heat-sealing films facing each other across the bag inner space in the internal space forming film portion. is there. A third characteristic configuration is that an exterior film that covers a formation location of the heat-sealed portion in the internal space forming film portion from outside is provided between the external space forming film portion and the bag outside and the film. The point is that it is attached to the outer surface of the internal space forming film portion in a state where an air passage communicating with the break opening is formed. A fourth characteristic configuration is that the film includes:
The present invention is characterized in that it has plasticity to maintain a shape in which the peripheral edge of the break opening protrudes toward the bag inner space.
A fifth characteristic configuration is that a packaging bag is formed by a laminated film formed by joining a plurality of base films,
In the laminate film, a non-joining portion for forming the air passage is formed at a part between the inner layer portion on the bag inner space side and the outer layer portion on the bag outer side, and the inner layer portion is formed in the inner space. It functions in that it functions as a film part for formation, and the outer layer part is configured to function as the exterior film. In a sixth characteristic configuration, the inner layer portion and the outer layer portion are configured such that a base film that cannot be thermally fused to each other is provided on a portion facing the inner layer portion and the outer layer portion. , Except that the non-joined portions are joined by an adhesive. A seventh characteristic configuration is that the inner layer portion is provided with plasticity that can maintain a shape in which a peripheral edge portion of the break opening portion protrudes toward the bag internal space. The eighth characteristic configuration is that the peripheral portion is heat-sealed to form a rectangular-shaped packaging bag, and the heat-sealed portion is disposed at a position biased to one side edge of the peripheral portion, and the one side edge thereof is provided. At the point where it is used as the entrance.

[0006]

The operation of the first characteristic configuration is as follows. When steam is generated from the object to be heated during the heat treatment and the internal pressure of the bag internal space rises, the film portion for forming the internal space expands, and the heat-sealed films are heat-sealed to each other. A tensile force is applied to pull the film in opposite directions from the portion, and the tensile force causes the film to break open at or near the periphery of the heat-sealed portion. Then, the steam in the bag internal space is released to the outside of the bag through the breaking opening, and the internal pressure of the bag internal space decreases.

The operation of the second feature is as follows. In order to form the heat-sealed portion, it is necessary to bring the films to be heat-sealed into contact with each other while facing each other. The packaging bag is in the form of a sheet in a state in which the film portion for forming the internal space is opposed to and opposed to each other across the internal space of the bag at the stage of manufacturing before forming the heat-sealed portion. Therefore, if the films facing each other across the bag inner space in the film portion for forming the internal space are partially heat-sealed to form a heat-sealed portion, particularly the heat-sealing portion for the heat-sealing is formed. Since it is not necessary to bring the films to be bonded into contact with each other while facing each other, it is possible to easily form the heat-sealed portion. Incidentally, it is supposed that the films on the same side of the film for forming the internal space and on the same side of the film for forming the internal space and separated from each other are thermally fused to each other. In this case, in order to make the films to be heat-fused contact each other in a state of facing each other, the film portions for forming the internal space in the state of being opposed to each other across the bag internal space are separated from each other, It is necessary to bend the planar film and bring the films to be heat-fused into contact with each other while facing each other, which complicates the operation.

The operation of the third characteristic configuration is as follows. With the generation of steam from the object to be heated during the heat treatment, the internal pressure of the bag inner space increases, and at or around the peripheral edge of the heat-sealed portion, the film breaks and opens,
The vapor in the bag interior space is discharged from the break opening to the outside of the bag through the ventilation path. At the time of opening of the film at the break opening, the liquid juice in the bag internal space scatters from the breaking opening. However, since the breaking opening is covered with the exterior film, the liquid juice can be prevented from scattering to the outside of the bag.

The operation according to the fourth characteristic configuration is as follows. When the film breaks and opens, the steam in the bag internal space is instantaneously released to the outside of the bag, and the internal pressure of the bag internal space decreases. Subsequently, when the heat treatment is performed, steam from the object to be heated is generated again, and the internal pressure in the bag inner space increases. At this time, when the heat-sealed films are completely separated from each other in the heat-sealed portion, the tensile force does not act, so the internal pressure of the bag inner space causes The air passage may be blocked by the close contact with the exterior film. On the other hand, according to the fourth characteristic configuration, as shown in FIG. 9, the peripheral portion of the break opening 1h of the internal space forming film portion I maintains the shape protruding toward the bag internal space S. As a result, the periphery of the break opening 1h is separated from the exterior film O. Therefore, when the internal pressure of the bag internal space S rises, the steam in the bag internal space S is generated by the internal space forming film portion I.
Into the air passage R from the space between the peripheral edge of the break opening 1h and the exterior film O, and pushes and spreads the tightly adhered internal space forming film portion I and the exterior film O to flow through the air passage R. And is released outside the bag.

The operation of the fifth feature is as follows. A heat-sealed portion obtained by partially heat-sealing the inner layer portions is formed at a non-joined portion at a portion of the inner layer portion of the laminate film facing the bag inner space. When steam is generated from the object to be heated during the heat treatment and the internal pressure of the bag internal space rises, the inner layers of the heat-sealed portions are pulled in opposite directions with respect to the heat-sealed portions as a base point. A force acts, and the tensile force causes the inner layer portion to break open at or near the periphery of the heat-sealed portion. Then, the steam in the bag interior space is released from the break opening to the outside of the bag through the non-joining portion functioning as a ventilation path, and the internal pressure of the bag interior space decreases. That is, the present invention can be applied to a packaging bag formed of a laminate film. By the way, if a print for displaying a description of stored items or the like is applied to the outer surface of the inner layer portion, the printed surface is covered by the outer layer portion, so that the print is not easily erased, and the laminate film has excellent durability.

The operation of the sixth feature is as follows. The laminate film is formed by bonding a plurality of base films with an adhesive, but in the process of forming, simply providing a part where the adhesive is not partially interposed between the inner layer portion and the outer layer portion. Thus, a non-joined portion can be formed. By the way, when forming the heat-sealed portion, the entire laminated film is brought into contact with the inner layer portion facing inside, and the laminated films on both sides are partially heated and pressed. Therefore, when the heat-sealed portion is formed, the base films on both sides facing the non-joined portion are pressed and heated in a state where they are in contact with each other, but they cannot be heat-sealed to each other. As a result, only the inner layer portions can be thermally fused to each other. Incidentally, it is also conceivable that the inner layer portion and the outer layer portion are separated from each other, and only the inner layer portions are brought into contact with each other in a state where they face each other, thereby forming a heat-sealed portion. The operation of contacting only the members facing each other becomes very complicated and not practical.

According to the seventh characteristic configuration, as shown in FIG. 15, the periphery of the break opening 4h of the inner layer portion 4I maintains the shape protruding toward the bag inner space S, so that the inner layer portion The periphery of the breaking opening 4h of 4I is in a state of being separated from the outer layer portion 4O. Therefore, after the break opening of the inner layer portion 4I, the inner layer portion 4I and the outer layer portion 40 are formed in the ventilation path R.
Is in close contact with the bag,
Rises, the steam in the bag inner space S enters the air passage R from the space between the peripheral portion of the break opening 4h of the inner layer portion 4I and the outer layer portion 4O, and the inner layer portion 4I is brought into tight contact with the inner layer portion 4I. The outer layer portion 40 is pushed and spread to flow through the air passage R, and is discharged to the outside of the bag.

The operation of the eighth feature is as follows. The packaging bag can be easily formed by laminating the laminated films with the inner layer portion inside, and heat-sealing the peripheral edge of the laminated state.
Since the heat-sealed portion is arranged at a position deviated to one side edge in the peripheral portion of the rectangular packaging bag, the heat-sealed portion is minimized from hindering the storage of the packaging object, The space inside the bag can be widened. In addition, since the side edge opposite to the one side edge in which the heat-sealed portion is biased is used as the entrance, the entrance can be widely opened.

[0014]

According to the first characteristic configuration, when steam is generated from an object to be heated at the time of heat treatment in a microwave oven or the like and the internal pressure of the bag internal space rises, the film forms a peripheral portion of the heat-sealed portion. Part or in the vicinity of the opening, the steam in the bag internal space is released to the outside of the bag through the breaking opening, and the internal pressure of the bag internal space is reduced. Burst can be prevented without performing such a troublesome treatment.

According to the second characteristic configuration, since the heat-sealed portion can be easily formed, an increase in manufacturing cost due to the implementation of the present invention can be suppressed as much as possible.

According to the third characteristic configuration, the liquid juice can be prevented from scattering to the outside of the bag, so that the trouble of cleaning the microwave oven or the like can be reduced as much as possible, and a convenient packaging bag can be provided. be able to.

According to the fourth feature, even if the internal pressure of the bag internal space rises again after the film breaks and opens, the vapor in the bag internal space is released to the outside of the bag, so that the bag is more reliably. Burst can be prevented.

According to the fifth characteristic configuration, a packaging bag which can prevent rupture at the time of the heat treatment, and which is hard to erase the display printing of the description of the stored items and the like, and has excellent durability can be provided. be able to.

According to the sixth aspect of the present invention, when the present invention is applied to a packaging bag formed of a laminate film, the present invention can be carried out by a simple modification of the existing manufacturing equipment for the laminate film, and furthermore, the heat sealing is performed. Since the portion can be easily formed, an increase in manufacturing cost due to the implementation of the present invention can be suppressed as much as possible.

According to the seventh characteristic configuration, even in a packaging bag formed of a laminated film, even if the internal pressure of the internal space of the bag rises again after the inner layer portion of the laminated film is broken open, the internal bag of the bag is not damaged. Since the vapor in the space is released to the outside of the bag, the burst can be more reliably prevented.

[0021] According to the eighth feature, the space inside the bag can be widened while preventing the rupture during the heat treatment, and the entrance portion is wide open so that the object to be packaged can be easily inserted. Therefore, practicality can be improved.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [First Embodiment] A first embodiment of the present invention will be described below with reference to FIGS. As shown in FIG. 2, the packaging bag is formed by a polyethylene film 1 so as to store food E as an object in a vacuum-sealed state. The food E is stored in a sealed state and can be cooked with a microwave oven or the like. To further explain, as shown in FIG. 1, two rectangular sheet-shaped polyethylene films 1 are overlapped, three side edges are heat-sealed, and the side edges not heat-sealed are sealed. It is designed to be used as an entrance when food E is put into the internal space S.

Further, in the film portion I of the polyethylene film 1 for forming an internal space facing the bag internal space S,
Two heat-sealed portions H are formed by partially heat-sealing the polyethylene films 1 in an oval shape so that a tensile force acts as the internal pressure of the bag internal space S increases. The heat-sealed portion H will be described. The heat-sealed portion S is formed by partially heat-sealing polyethylene films opposed to each other across the bag inner space S in the film portion I for forming the inner space. I have. Further, the heat-sealed portion H is arranged at a position deviated from the side edge facing the side edge used as the entrance. The heat-sealing condition when forming the heat-sealed portion H is based on the heat-sealing condition when the side edges of the two sheet-like polyethylene films 1 are superposed as described above. A little bit stronger, polyethylene film 1
In the above, the strength of the peripheral portion of the heat-sealed portion H or the vicinity thereof is slightly weaker than other portions. In order to strengthen the heat fusion conditions, for example, the temperature or pressure at the time of heating and pressing may be increased, or the time may be lengthened.

As shown in FIG. 1, food E is stored from the entrance into the bag interior space S of the packaging bag in which the two heat-sealed portions H are formed, and then the side edge of the packaging bag used as the entrance is removed. The bag interior space S is vacuum-sealed as shown in FIG.

Next, based on FIG. 3 and FIG. 4, the polyethylene film 1 is melted by heat as the internal pressure of the bag inner space S rises due to the steam generated from the food E during cooking. The process of breaking open at the periphery of the attachment portion H or in the vicinity thereof will be described. As shown in FIG. 3, when steam is generated from the food E due to heating, the internal pressure of the bag internal space S increases, and the internal space forming film portion I expands. Then, a tensile force acts on the heat-sealed polyethylene films in directions opposite to each other with the heat-sealed portion H as a base point. Since the strength of the polyethylene film 1 at or near the peripheral portion of the heat-fused portion H is weaker than other portions, the strength of the polyethylene film 1 at or near the peripheral portion of the heat-fused portion H is higher than the tensile strength. When it cannot withstand the force, as shown in FIG. 4, the polyethylene film 1 breaks and opens, and the steam in the bag inner space S is discharged to the outside of the bag through the break opening portion 1h, and the inside of the bag inner space S is released. The pressure drops.

Second Embodiment A second embodiment of the present invention will be described below with reference to FIGS. In the second embodiment, as in the first embodiment, the packaging bag is formed by laminating two rectangular sheet-like polyethylene films 1 and heat-sealing the periphery thereof to form a vacuum-sealed state. Food E
And two heat-sealed portions H are formed. Further, as shown in FIG. 5, the heat-sealed portions H in the internal space forming film portion I are formed outside. The exterior polyethylene film 2 as the exterior film O to be covered from the side is inserted between the exterior of the bag and the break opening 1
h, and is provided on the outer surface of the film portion I for forming an internal space in a state in which a ventilation path R communicating with the inner space h is formed.

The exterior polyethylene film 2 will be described. As in the first embodiment, in the packaging bag in which the three side edges are heat-sealed and the heat-sealed portion H is formed, the outer surface of the internal space forming film portion I is provided with an exterior polyethylene. The film 2 is joined in a state where a non-joining portion 1n that functions as a band-shaped air passage R extending between a pair of opposing side edges is formed. Non-joined part 1n
Is formed in a state where the heat-sealed portion H is located within the range. The sheet-like polyethylene film 1 and the exterior polyethylene film 2 are joined with the adhesive 3 in a range excluding the non-joined portion 1n. The adhesive 3 includes a urethane resin, a vinyl acetate resin, a natural rubber, and the like.
The material dissolved in organic resin is applied and used. Then, as described above, the food E is stored in the bag interior space S of the packaging bag to which the exterior polyethylene film 2 has been joined, as in the first embodiment, from the entrance, as shown in FIG. Then, the side edge of the packaging bag used as the entrance is heat-sealed to vacuum seal the bag interior space S.

Next, based on FIGS. 6 to 9, the polyethylene film 1 is heated and cooked by the steam generated from the food E when the internal pressure of the bag interior space S is increased. The process of breaking open at the periphery of the attachment portion H or in the vicinity thereof will be described. As shown in FIGS. 6 and 7, when steam is generated from the food E due to heating, the internal pressure of the bag internal space S increases, and the internal space forming film portion I expands. Then, a tensile force acts on the heat-sealed polyethylene films in directions opposite to each other with the heat-sealed portion H as a base point.
Since the strength of the polyethylene film 1 at or near the peripheral portion of the heat-sealed portion H is weaker than other portions,
When the strength of the polyethylene film 1 at or near the peripheral portion of the heat-sealed portion H cannot withstand the tensile force, as shown in FIG. Through 1n, the steam in the bag internal space S is released to the outside of the bag, and the internal pressure of the bag internal space S decreases. Accordingly, the non-joined portion 1n functions as an air passage R that connects the outside of the bag and the break opening 1h of the polyethylene film 1.

When the polyethylene film 1 breaks and opens, steam in the bag internal space S is instantaneously released to the outside of the bag, and the internal pressure of the bag internal space S decreases. When the food E is subsequently cooked, steam is generated again from the food E, and the internal pressure in the bag interior space S rises. In this state, when the polyethylene films that have been heat-sealed at the heat-sealed portion H are completely separated from each other, the tensile force does not act. In some cases, the film portion I and the polyethylene film for exterior 2 come into close contact with each other and the air passage R is blocked. On the other hand, since the polyethylene film 1 has plasticity, as shown in FIG. 9, the peripheral edge of the break opening 1h keeps the shape protruding toward the bag internal space S. Therefore, since the periphery of the break opening 1h is separated from the exterior polyethylene film 2, the bag inner space S
When the internal pressure of the polyethylene film 1 rises, the vapor in the bag internal space S enters the air passage R from the space between the peripheral portion of the break opening 1h of the polyethylene film 1 and the exterior polyethylene film 2 and comes into close contact with the polyethylene film 1. 1 and the exterior polyethylene film 2 are pushed and spread, and flow through the air passage R to be discharged to the outside of the bag.

Third Embodiment Hereinafter, FIGS. 10 to 15 will be described.
A third embodiment of the present invention will be described based on FIG. As shown in FIGS. 10 and 11, the packaging bag in the third embodiment is formed of a laminate film 4 formed by joining a plurality of base films. As shown in FIG. 12, the laminated film 4 is formed by bonding a nylon base film 4a and a polyethylene base film 4b, which cannot be thermally fused to each other, with an adhesive 5. To add further explanation, as shown in FIG. 10, two rectangular sheet-like laminated films 4 were
Are superimposed on each other inwardly, and three side edges are heat-sealed, and the side edge that is not heat-sealed is used as an entrance when the food E is put into the bag interior space S. Therefore, the polyethylene base film 4b corresponds to the inner layer part 4I on the bag inner space S side of the laminate film 4, and the nylon base film 4a corresponds to the outer layer part 40 of the laminate film 4 on the bag outer side. One of the two sheet-like laminated films 4 is located at a position biased to a side edge opposite to a side edge that is not heat-sealed, and a nylon base film 4a and a polyethylene base film 4b are attached. A strip-shaped non-joining portion 4n that is not joined is formed. The band-shaped non-joining portion 4n extends between a pair of side edges facing each other. In addition, the nylon base film 4a and the polyethylene base film 4b
Bonding is performed with the adhesive 5 in a range excluding n.
When the side edges of the two sheet-like laminated films 4 are heat-sealed, the nylon base film 4a and the polyethylene base film 4b are in contact with each other at the non-joined portion 4n. However, since both are not thermally fused, the non-joined portion 4n is not joined.

Then, the two sheet-like laminated films 4 are partially pressed and heated from both sides at the non-joined portion 4n, so that the polyethylene base films facing each other with the bag inner space S interposed therebetween are partially separated. The heat-sealed portion H having an oval shape is formed by heat-sealing. Note that two heat-sealed portions H are formed. At this time, the nylon base film 4a and the polyethylene base film 4b are also pressed and heated in a state where they are in contact with each other, but they are not thermally fused.

Then, as shown in FIG. 10, the food E is stored from the entrance into the bag interior space S of the packaging bag in which the two heat-sealed portions H are formed, and thereafter, the side of the packaging bag used as the entrance. The edge is heat-sealed to vacuum seal the bag inner space S.

Next, based on FIG. 12 to FIG. 15, when the inside pressure of the bag interior space S is increased by the steam generated from the food E during the heating and cooking, the polyethylene base film 4b is The process of breaking open at the peripheral edge of the heat-sealed portion H or in the vicinity thereof will be described. FIG.
As shown in FIG. 2 and FIG. 13, when steam is generated from the food E due to heating, the internal pressure of the bag internal space S increases, and the laminate film 4 expands. Then, a tensile force acts on the heat-fused polyethylene base films in directions opposite to each other with the heat-sealed portion H as a base. At or near the periphery of the heat-sealed portion H,
When the strength of the polyethylene base film 4b cannot withstand the tensile force, as shown in FIG. 14, the polyethylene base film 4b breaks and opens, and through the break opening 4h through the non-joining portion 4n, the bag inner space S The steam inside is released to the outside of the bag, and the internal pressure of the bag internal space S decreases. Therefore, the non-joined portion 4n functions as an air passage R that connects the outside of the bag and the break opening 4h of the polyethylene base film 4b.

When the polyethylene base film 4b is broken open, the steam in the bag interior space S is instantaneously released to the outside of the bag, and the internal pressure of the bag interior space S decreases. When the food E is subsequently cooked, steam is generated again from the food E, and the internal pressure in the bag interior space S rises. In this state, if the polyethylene base films that have been heat-sealed at the heat-sealed portion H are completely separated from each other, the tensile force does not act. There is a case where the material film 4b and the nylon base film 4a come into close contact with each other and the air passage R is closed. On the other hand, since the polyethylene base film 4b has plasticity, as shown in FIG. 15, the peripheral edge of the break opening 4h maintains the shape protruding toward the bag inner space S side. Accordingly, since the peripheral edge of the breaking opening 4h is separated from the nylon base film 4a, when the internal pressure of the bag internal space S rises, the steam in the bag internal space S is generated by the polyethylene base film 4b. Of the break opening 4h and the nylon base film 4a into the air passage R from the space between the peripheral part of the break opening 4h and the tightly adhered polyethylene base film 4b and the nylon base film 4a. It flows and is released outside the bag. Therefore, the polyethylene base film 4b functions as the film portion I for forming the internal space in the first and second embodiments, and the nylon base film 4a functions as the exterior film O in the second embodiment.

Next, an example in which the above-mentioned laminated film 4 is manufactured by a dry laminating method will be described with reference to FIGS. The nylon base film 4a unwound from the first roll 10 is guided to the coating section A, and is coated on one surface of the nylon base film 4a by the coating roll 12 and the rubber roll 13 immersed in the adhesive 5 in the tank 11. The adhesive 5 is applied. An annular groove 12 is provided on the outer peripheral surface of the coating roll 12.
a is formed, and a non-transfer portion 5n to which the adhesive 5 is not transferred is formed in a portion corresponding to the annular groove 12a in the nylon base film 4a. Then, the nylon base film 4a sent from the coating unit A via the drying furnace 15 and the second roll 14
And the polyethylene base film 4b drawn out of the base film 4b is guided to the laminating section C, and the base film 4b
After laminating a and 4b with a heating metal roll 16 and a rubber roll 17, the laminated film 4 is cooled by a cooling roll 18 and wound around a third roll 19. Therefore, the non-transferred portion 5n forms the non-joined portion 4n.
The adhesive 5 includes a urethane-based resin, a vinyl acetate-based resin, a natural rubber, and the like, and is used after being dissolved in an organic resin.

Then, the laminated film 4 manufactured as described above is cut into a rectangular sheet and used. still,
When the sheet is cut into a sheet, both the sheet having the non-joined part 4n and the sheet not having the non-joined part 4n may be cut from the laminated film 4 manufactured as described above. Alternatively, from the laminated film 4 manufactured as described above, only the sheet-shaped laminated film 4 having the non-joined portion 4n is cut, and the sheet-shaped laminated film 4 having no non-joined portion 4n is cut. In order to cut, using the coating roll 12 in which the annular groove 12a is not formed, the laminated film 4 in which the nylon base film 4a and the polyethylene base film 4b are joined with the adhesive 5 on the entire surface is manufactured. You may.

[Another Embodiment] Next, another embodiment will be described. (B) In each of the above embodiments, the shape of the heat-sealed portion H is an oval shape, but the shape of the heat-sealed portion H can be changed.
For example, the shape may be a circle, a rectangle, a cross, or a band. (B) In each of the above embodiments, the case where two heat-sealed portions H are arranged at a position deviated to one side edge in the peripheral portion of the rectangular packaging bag is illustrated, but the heat-sealed portions H are arranged. The position and the number of the positions can be variously changed. For example, one or three or more may be arranged at a position biased to one side edge. In addition, in each of the above-described embodiments, the heat-sealed portion H may be arranged so as to be offset to the side edge other than the side edge where the heat-sealed portion H is arranged to be offset. (C) In the third embodiment, the heat-sealed portion H may be formed in a state where the two rectangular sheet-like laminated films 4 are shifted from each other in the plane direction. In this case, the tensile force acting on the heat-sealed polyethylene base films is further increased, so that the polyethylene base film 4b is easily broken and opened.

(D) In the first and second embodiments, the polyethylene film 1 is broken open at the entire periphery of the peripheral portion of the heat-sealed portion H or the entire periphery thereof. The case where the fused polyethylene films are completely separated from each other has been described. It is also conceivable that the polyethylene films do not separate from each other. Further, in the third embodiment, the polyethylene base film 4b breaks and opens on the entire periphery of the peripheral portion of the heat-sealed portion H or on the entire periphery thereof,
Although the case where the polyethylene base films which are heat-sealed at the heat-sealed portion H are completely separated from each other has been described,
It is also conceivable that the polyethylene base film 4b breaks and opens at a part of the periphery of the heat-sealed portion H or at a part near the periphery, and the heat-sealed polyethylene base films do not separate from each other. As described above, even when the polyethylene film 1 or the polyethylene base film 4b breaks and opens at a part of the peripheral portion of the heat-fused portion H or at a part in the vicinity thereof, the entire periphery of the peripheral portion of the heat-fused portion H The same operation and effect as in the case where the fracture opening is formed in the entire periphery in the vicinity can be obtained.

(E) In the first and second embodiments, the case where polyethylene is applied as a specific material of the film forming the packaging bag is illustrated, but various materials may be applied in addition to this. It is possible, for example, polypropylene. Further, in the second embodiment, the case where polyethylene is applied as a specific material of the exterior film O is illustrated, but various other materials can be applied, for example, nylon, polypropylene, It may be paper.

(F) In the above-described second embodiment, the case where the exterior film O is attached before storing the food in the packaging bag is illustrated. Instead, the food is stored in the packaging bag and sealed. It may be attached after doing. In this case, the exterior film O may also be used as a label for explaining the food.

(G) In the third embodiment, one of the two sheet-like laminated films 4 has a non-bonded portion 4n
However, the non-joined portion 4n is provided on each of the two sheet-like laminated films 4, and the two sheet-like laminated films 4 are stacked such that the non-joined portions 4n are plane-symmetric with each other. May be combined.

(H) In the third embodiment, the inner layer portion 4I and the outer layer portion 40 of the laminated film 4 are
Although the case where each is constituted by one base film is illustrated, any one or both of the inner layer part 4I and the outer layer part 40 may be constituted by two or more base films. (I) In each of the above embodiments, the case where the packaging bag is formed by stacking two sheet materials is illustrated. Alternatively, the packaging bag may be formed by folding one sheet material. Or it may be formed of a tubular material.

(V) In the third embodiment, the case where the laminated film 4 is manufactured by the dry laminating method has been described as an example.
For example, it can be manufactured by a wet lamination method, an extrusion lamination method, a hot melt lamination method, or a co-extrusion lamination method.

Incidentally, reference numerals are written in the claims for convenience of comparison with the drawings, but the present invention is not limited to the configuration of the attached drawings by the entry.

[Brief description of the drawings]

FIG. 1 is a perspective view of a packaging bag before an object is stored in a first embodiment.

FIG. 2 is a perspective view of a packaging bag storing an object in a sealed state in the first embodiment.

FIG. 3 is a cross-sectional plan view of the packaging bag before the nylon film is broken open in the first embodiment.

FIG. 4 is a cross-sectional plan view of the packaging bag after the nylon film has been broken open in the first embodiment.

FIG. 5 is a perspective view of a packaging bag storing an object in a sealed state in a second embodiment.

FIG. 6 is a cross-sectional plan view of the packaging bag before the nylon film is broken open in the second embodiment.

FIG. 7 is a longitudinal sectional side view of a packaging bag before a nylon film is broken open in a second embodiment.

FIG. 8 is a cross-sectional plan view of the packaging bag after the nylon film has been broken open in the second embodiment.

FIG. 9 is a cross-sectional plan view of the packaging bag after the nylon film has been broken open in the second embodiment.

FIG. 10 is a perspective view of a packaging bag before storing an object in the third embodiment.

FIG. 11 is a perspective view of a packaging bag storing an object in a sealed state in a third embodiment.

FIG. 12 is a cross-sectional plan view of the packaging bag before the nylon film is broken open in the third embodiment.

FIG. 13 is a vertical cross-sectional side view of the packaging bag before the nylon film is broken open in the third embodiment.

FIG. 14 is a cross-sectional plan view of the packaging bag after the nylon film has been broken open in the third embodiment.

FIG. 15 is a cross-sectional plan view of the packaging bag after the nylon film has been broken open in the third embodiment.

FIG. 16 is a schematic view showing a manufacturing process of a laminated film by a dry laminating method.

FIG. 17 is a perspective view of a coating part in a dry lamination method.

FIG. 18 is a perspective view of a laminating part in a dry laminating method.

[Explanation of Signs] 1 Film 1h, 4h Breaking opening 4 Laminating film 4a, 4b Base film 4n Non-bonding part 4I Inner layer part 4O Outer layer part 5 Adhesive H Heat fusion part I Internal space forming film part O Exterior film R air passage S bag inner space

Claims (8)

(57) [Claims] 1. A film (1) made of a synthetic resin,
A packaging bag formed so as to store an object in a sealed state, wherein the film (1) has an internal space forming film portion (I) facing the bag internal space (S), and A heat-sealed portion (H) in which the films are partially heat-sealed so that a tensile force acts as the internal pressure of the space (S) increases.
And a packaging bag configured to be capable of being broken open at or near the peripheral edge of the heat-sealed portion (H) by the tensile force caused by the internal pressure. 2. The heat-sealing portion (H) partially heat-fuses films facing each other across the bag inner space (S) in the internal space forming film portion (I). The packaging bag according to claim 1, wherein the packaging bag is constituted by: 3. The film portion (I) for forming an internal space.
An outer film (O) that covers the location where the heat-sealed portion (H) is formed from outside is provided between the outside of the bag and the break opening of the film (1) between the film portion (I) for forming the internal space. 3. The packaging bag according to claim 1, wherein the packaging bag is attached to an outer surface of the internal space forming film portion (I) in a state where a ventilation path (R) communicating with the portion (1 h) is formed. 4. The film (1) according to claim 3, wherein the film (1) has plasticity so that the peripheral portion of the breaking opening (1h) can maintain a shape in a state of protruding toward the bag internal space (S). Packaging bag. 5. A plurality of base films (4a), (4b)
A packaging bag is formed of the laminated film (4) formed by bonding the inner layer (4I) of the laminated film (4) on the side of the bag inner space (S) and the outer layer of the outer layer ( 4
O), a non-joining portion (4n) for forming the ventilation path (R) is formed, and the inner layer portion (4I) serves as the internal space forming film portion (I). Function and the outer layer portion (4O)
The packaging bag according to claim 3, wherein the packaging bag is configured to function as the exterior film (O). 6. A structure in which the inner layer portion (4I) and the outer layer portion (4O) are provided with base films (4a) and (4b) that cannot be thermally fused to each other at their opposing portions. The inner layer portion (4I) and the outer layer portion (4O) are bonded to the adhesive (5) in a range excluding the non-joined portion (4n).
The packaging bag according to claim 5, which is joined by: 7. The inner layer portion (4I) is provided with plasticity capable of maintaining a shape in which a peripheral edge of a break opening (4h) protrudes toward the bag inner space (S).
Or the packaging bag of 6. 8. A packaging bag is formed in a rectangular shape by heat-sealing a peripheral portion, and the heat-sealed portion (H) is arranged at a position deviated to one side edge of the peripheral portion, and one side thereof. The packaging bag according to claim 1, 2, 3, 4, 5, 6, or 7, wherein a side edge facing the edge is used as an entrance.