JP2002002779A - Food packaging film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a packaging film which is not inconvenient in packaging food, wherein both surfaces of a packaging bag can be easily and appropriately separated from each other at a heat-sealed portion. SOLUTION: The food packaging film includes an oriented base film layer 1 on a side to be an exterior of the packaging bag H and a non-oriented sealant layer 2 on a side to be an interior of the bag H. The base film layer 1 comprises a polyethylene terephthalate(PET). The sealant layer 2 comprises a polyethylene(PE) layer 2a, a crystalline polypropylene(PP) layer 2b and a non-crystalline PP layer 2c wherein these three layers are laminated in this sequence from an adhesive side to the base film layer 1 toward a side opposite to the adhesive side. By pulling both surfaces 4 and 4 of the packaging bag H in separating directions, interface peeling occurs between the non-crystalline PP layer 2c on a side of one of surfaces 4 of the bag H and the non-crystalline PP layer 2c on a side of the other surface 4, which are welded to each other at the heat-sealed portion.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a first heat seal which is continuously applied in a direction along a film transport direction, and a second heat seal which is applied in a direction crossing the transport direction. Is a packaging film that constitutes a three-side sealed packaging bag or a four-side sealed packaging bag that is sequentially formed while filling an object to be packaged, and is pulled in a direction to separate both surfaces of the packaging bag. Accordingly, the present invention relates to a food packaging film capable of easily separating both sides of the heat-sealed packaging bag at the heat-sealed portion and taking out the packaged object.

[0002]

2. Description of the Related Art In order to take out a filled food from a packaging bag filled with a food formed by a three-side seal package or a four-side seal package, there has been no other way than to cut the packaging bag and open it. As a method of facilitating the removal, there are a method of using the packaging film as a material having easy tearability and a method of providing a notch in the packaging bag. However, all of these methods assume that the packaging bag is torn.

[0003]

SUMMARY OF THE INVENTION The present applicant pulls both sides of a packaging bag formed of the three-sided seal package or the four-sided seal package so that the heat-sealed portions of the heat-sealed portion are joined together. Both sides can be easily separated, and the objects packed in the packaging bag by these packages can be used regardless of whether the objects are evenly filled in the packaging bag. Regardless of the properties of objects, we have invented a technique that can be easily and appropriately taken out, and filed an application related to this technique first. (Japanese Patent Application No. 11-11155, Japanese Patent Application No. 11-882)
No.44, Japanese Patent Application No. 11-263566)

[0004] Thereafter, the applicant of the present invention did not inconvenience the food packaging by the three-side seal packaging or the four-side seal packaging,
In addition, the present inventors further studied a packaging film capable of easily and appropriately separating both sides of the packaging bag in the heat-sealed portion, and reached the packaging film according to the present application.

[0005] That is, an object of the present invention is to provide a packaging film capable of easily and appropriately separating both sides of a packaging bag in a heat-sealed portion without inconvenience in packaging of food by three-side seal packaging or four-side seal packaging. In the offer.

[0006]

In order to achieve the above object, the present invention provides a food packaging film having the following constitutions (1) to (5). (1) Packaging is performed by a first heat seal continuously applied in a direction along a film transport direction and a second heat seal applied at intervals in a direction crossing the transport direction. A packaging film for forming a three-side sealed packaging bag or a four-side sealed packaging bag formed successively while filling an object, wherein (2) the packaging film is stretched on the side outside the packaging bag. The film layer has a non-stretched sealant layer laminated to the base film layer via an adhesive on the side that is the inside of the packaging bag,
(3) The base film layer includes at least a surface layer composed of polyethylene terephthalate (hereinafter, also referred to as a PET layer in the present specification).
(4) The sealant layer has a polyethylene layer (hereinafter, also referred to as a PE layer in the present specification) and a crystalline polypropylene layer (from the adhesive side to the base film layer toward the side opposite to the adhesive side). Hereinafter, in the present specification, the three layers are laminated in the order of a crystalline PP layer) and a non-crystalline polypropylene layer (hereinafter, also referred to as a non-crystalline PP layer in the present specification). (5) One side of the packaging bag, which is welded to each other at the portion where the first and second heat seals have been performed, by pulling the packaging bag in a direction to separate both surfaces of the packaging bag. Interfacial separation occurs between the non-crystalline polypropylene layer and the non-crystalline polypropylene layer on the other side of the packaging bag.

[0007] According to this configuration, by pulling in a direction to separate both surfaces of the packaging bag, one of the packaging bags welded to each other at the first and second heat-sealed portions. By causing interfacial separation between the non-crystalline polypropylene layer on the surface side and the non-crystalline polypropylene layer on the other surface side of the packaging bag, the packaged object is cut without tearing the packaging bag. It can be taken out smoothly from inside the packaging bag.

[0008] Stretched PET constituting the base film layer
Has good transparency, low hygroscopicity and low water absorption, and is excellent in heat resistance and the like, so that food can be appropriately packaged by three-side seal packaging or four-side seal packaging.

Further, the amorphous P constituting the sealant layer
The P layer has a higher heat melting temperature than polyethylene but lower than crystalline polypropylene, and has a wide heat sealable temperature range. Therefore, the packing bag is formed at a high speed by a filling and packaging machine that forms a three-side seal package or a four-side seal package. Can be done.

[0010] Further, the amorphous P
The P layer is pulled in such a direction that both sides of the packaging bag are separated from each other, so that the portion between the first and second heat-sealed portions and the non-crystalline PP layer on the other surface side of the packaging bag. It is recognized that thermal welding is easily performed in a state where interfacial separation easily occurs. That is, according to the food packaging film of the present invention, by pulling the packaging bag in a direction in which both sides of the packaging bag are separated from each other, the packaging constituting the interlayer and the other surface of the packaging film constituting one surface of the packaging bag is pulled. Without causing peeling between the layers of the film, so that peeling occurs only at the welded interface between the packaging film constituting one surface and the packaging film constituting the other surface, the food is three-side sealed packaging or Appropriate packaging can be achieved with four-sided seal packaging.

[0011] Further, the P film is
Where the sealant layer is bonded on the side of the E layer, there are many types of adhesives suitable for bonding the PE layer. Therefore, the range of selection of the adhesive for bonding the base film layer and the sealant layer is wide. Is wide.

The melting temperature of the crystalline PP layer is generally higher than the melting temperature of the amorphous PP layer. As a result, the crystalline PP layer between the PE layer and the non-crystalline PP layer hardly deteriorates due to a heat treatment or a freezing treatment such as boil sterilization of the article to be packed filled in the packaging bag, High durability of the packaging film against temperature changes can be ensured. Also, the crystalline PP layer can provide the packaging film with appropriate rigidity.

In addition, the amorphous PP layer and the crystalline PP layer are well adapted to each other in forming by the coextrusion multilayer method, and do not cause separation between the two layers.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A typical embodiment of a food packaging film according to the present invention will be described below with reference to FIGS.

Here, FIG. 1 shows a filling and packaging machine for continuously forming a packaging bag H (in the example shown in FIG. 1 a four-side sealed packaging bag) while filling the packaging material M with the packaging film F. FIG. 2 shows the outline of the configuration in a perspective view, and FIG. 2 shows the outline of the configuration as viewed from the side. FIG. 3 shows the heat sealing portion 3 of the packaging bag H formed by the packaging film F.
FIG. 3 is an enlarged configuration diagram showing a state where the two surfaces 4 and 4 are pulled in a direction to separate them, and separation of the interface is started. Also,
4 and 5 show an example of the packaging bag H,
FIG. 6 shows the heat seal portion 3 of the packaging bag H shown in FIG.
Is shown in a state where the packaged object M filled in the packaging bag H is taken out by interfacial separation. FIG. 7 shows an example of a packaging bag H which differs from the packaging bag H shown in FIGS. 4 to 6 in part of the configuration of the heat seal portion 3.

The food packaging film F according to this embodiment is provided with a first heat seal 8 continuously applied in a direction along the film transport direction x, and a gap in a direction crossing the transport direction x. The second heat seal 9 which is opened and applied constitutes a three-side seal packaging bag or a four-side seal packaging bag which is formed successively and sequentially while filling the object to be packaged M, and is suitable for food packaging. It is a thing.

The packaging bag H made of the packaging film F
Is typically made by a filling and packaging machine having the configuration shown in FIG.

The packing object M is filled by a heat sealing means 16 for applying the second heat seal 9 to the inside of the flat film F to which the first heat seal 8 is applied.
Filling tube 1 so that the discharge port 11a is located immediately above
1 and the discharge port 1 through the filling tube 11.
This is performed by feeding the packaged material M prepared in a fluid state by continuously or intermittently forming a mince from 1a.

The first heat seal 8 is provided by a heat seal means 15 composed of a pair of vertical heat rolls 15a, 15a whose rotation axes are arranged in a direction perpendicular to the transport direction x of the film F. You.

In the example shown in FIG. 1, a packaging film F drawn from a raw film indicated by reference numeral 13 in the figure is used.
Is folded in two by a two-fold means indicated by reference numeral 14, and a pair of the first pair of the first along the folding side y side and the side z opposite to the folding side y side of the packaging film F thus folded in two. The heat seal 8 is applied. That is, in the example shown in FIG. 1, the pair of vertical heating rolls 15a, 15a are respectively provided at both ends thereof at the folding side y side and the side opposite to the folding side y side in the folded packaging film F. An annular raised portion 15b that forms the outer flange that continuously applies the first heat seal 8 along the transport direction x of the packaging film F while drawing and sending the packaging film F to the edge of z. It has.

Then, the pair of vertical heat rolls 15a,
15a, the raised portion 15b is connected to another vertical heat roll 1
The packaging film F folded in half between the adjacent raised portions 15b is brought close to the raised portions 15b of the other vertical heating roll 15a while being brought close to the raised portions 15b on the side facing 5a. From the side of, and
It is configured to rotate in the opposite direction to the other vertical heat roll 15a so that the drawn-in packaging film F is sent out to the side of the heat sealing means 16 for applying the second heat seal 9.

The second heat seal 9 is provided by a heat seal means 16 comprising a pair of horizontal heat rolls 16a, 16a whose rotation axis is arranged in a direction perpendicular to the conveying direction x of the packaging film F. Is done.

In the example shown in FIG. 1, the pair of horizontal heating rolls 16a, 16a
The projecting ridges for applying the second heat seal 9 to the packaging film F to which the first heat seal 8 has been applied by a and 15a at predetermined intervals while drawing in and sending out the packaging film F. The part 16b is connected to the horizontal heat roll 16a.
Are provided so as to protrude along the direction of the rotation axis.

In this embodiment, the horizontal heating roll 16a has outer flanges 16c at both ends thereof, and the ridge 16b extends between the outer flanges 16c. Have. In the present embodiment, a plurality of ridges 16b are formed at intervals in the rotation direction of the horizontal heating roll 16a. And
The ridges 16b of the other horizontal heat roll 16a are sequentially arranged on the side where the ridges 16b of the pair of horizontal heat rolls 16a face the other horizontal heat roll 16a with the rotation of the horizontal heat roll 16a. And the packaging film F drawn between the pair of horizontal heat rolls 16a, 16a intermittently so as to be abutted against
6b, the second heat seal 9 is provided.

In the example shown in FIG. 1, the packaging material M is filled with the first heat seal 8 and the second heat seal 9 applied as described above to form a continuous state. At the next position of the feed roller 10 for transporting the bags H, cutting is performed on the packaging bags H formed in such a continuous state within the width of the second heat seal 9 and cut into individual packaging bags H. Means 12 are provided.

Various kinds of foods are expected as the article M to be packed in the packaging bag H. Typically, a food that has fluidity in the filling step and that solidifies by the passage of time thereafter or by subsequent heating or freezing treatment in a state of being packed in the packaging bag H is expected.

The three-side sealed packaging bag is a packaging bag H formed by three-side sealed packaging. Such a three-sided seal package is formed by folding the long packaging film F in two while transporting the packaging film F in a state where the length direction of the packaging film F is along the transport direction x, and in the transport direction x of the packaging film F. The first heat seal 8 is applied continuously in the direction along the second heat seal 9, and the second heat seal 9 is applied at intervals in the direction crossing the transport direction x to apply at least three sides (folding) other than the folding side y. One or more first heat seals 8 may be further provided between the side y and the first heat seal 8 so that the packaging bag H has a plurality of divided storage spaces.) The heat sealing portion 3 is formed, and the packaging bags H in which the objects to be packaged M are sealed are sequentially and continuously formed.

The four-side sealed packaging bag H is a packaging bag H formed by four-side sealed packaging. In such a four-side seal packaging, in a state where the long packaging film F is folded in two, or in a state where the two packaging films F and F face each other, the length direction of the packaging film F is set in the transport direction x. While transporting along the state, the packaging film F
A pair of first heat seals 8 and 8 are continuously applied in a direction along the conveyance direction x, and a second heat seal 9 is provided at intervals in a direction crossing the conveyance direction x to at least Heat may be applied to four sides (one or more first heat seals 8 may be further provided between the pair of heat seals 8, 8 so that the packaging bag H has a plurality of divided storage spaces). The sealing portion 3 is formed so that the packaging bags H in which the items to be packaged M are sealed are formed sequentially and continuously.

The first and second heat seals 8 and 9 are applied to the food packaging film F according to the present embodiment by pulling the food packaging film F in a direction in which both sides 4 and 4 of the packaging bag H are separated. A non-crystalline polypropylene layer 2c, which will be described later, on one surface 4 of the packaging bag H and a non-crystallizing material on the other surface 4 side of the packaging bag H, which are welded to each other at the sealed portion (heat seal portion 3). 2e between the polypropylene layer 2c
This causes interfacial peeling. That is, by pulling the two sides 4, 4 of the packaging bag H in a direction to separate them, the layers of the packaging film F constituting the one surface 4 of the packaging bag H and the packaging film F constituting the other surface 4 are formed. The peeling is caused only at the welded interface between the packaging film F constituting the one surface 4 and the packaging film F constituting the other surface 4 without causing the peeling between the layers.

The three-side sealed packaging bag or the four-side sealed packaging bag is formed of the film F which is heat-sealed so as to be peelable at the interface so that the food to be packaged can be smoothly taken out from the packaging bag H. To do that.

That is, if the three-side sealed packaging bag or the four-side sealed packaging bag is formed of such a packaging film F having a sealant layer 2 which is heat-sealed so as to be peelable at an interface, any one side of the packaging bag H can be obtained. The heat-sealed portion 3 is applied so that an unsealed portion 6 is formed between the edge 5 of the packaging film F and the outer edge of the heat-sealed portion 3 facing the edge 5 of the packaging film F. By doing so, the heat sealing portion 3 can be easily broken by pulling the unsealed portion 6 as a stripping margin in a direction in which both sides 4 and 4 of the packaging bag H are separated, and the pulling operation can be continued. The heat seal portions 3, 3 on two sides of the packaging bag H adjacent to the heat seal portion 3 on one side broken by doing so are continuously broken, and the three sides have
And the enclosed food can be easily taken out. (FIGS. 4 and 6)

From the viewpoint of facilitating the opening operation using the unsealed portion 6 of the packaging bag H as a stripping margin, the edge 5 of the film on the one surface 4 side of the packaging bag H in the unsealed portion 6 is used. In a state where the edges 5 of the film on both sides 4 and 4 are shifted in the unsealed portion 6 so as to be positioned inside the edge 5 of the film on the other surface 4 side, the heat on the unsealed portion 6 side is shifted. It is preferable to form the seal portion 3. (FIG. 5) Thus, the film edges 5 on both sides 4, 4 of the packaging bag H
If the position is shifted, it is easy to hold the both sides 4 and 4 of the packaging bag H in the unsealed portion 6 prior to performing the pulling operation for opening.

Further, from the viewpoint of facilitating the opening operation with the unsealed portion 6 of the packaging bag H being peeled off,
The outer edge of the heat seal portion 3 on the side of the unsealed portion 6 becomes a mountain-shaped or wavy edge 3a formed so as to have a top 3b toward the unsealed portion 6 side. It is preferable to form the seal portion 3 in advance. (FIG. 7) If such a heat seal portion 3 is formed,
The unsealed portion 6 is used as a stripping margin on both sides 4 of the packaging bag H,
4 is pulled away from the heat-sealing portion 3 so as to concentrate on the top portion 3b.
This is because the heat seal portion 3 can be more easily broken from the side.

More specifically, in the packaging film F according to the present embodiment, the stretched base film layer 1 is provided on the outer side of the packaging bag H, and on the inner side of the packaging bag H. An unstretched sealant layer 2 (so-called dry lamination) laminated to the base film layer 1 via an adhesive is provided.

As the adhesive 1a for bonding the base film layer 1 and the sealant layer 2, typically, a polyester adhesive or a polyether urethane adhesive can be used. In this embodiment, when the sealant layer 2 is bonded to the base film layer 1 on the side of the PE layer, there are many types of adhesives suitable for bonding the PE layer. There is a merit that the selection range of the adhesive 1a for bonding the film layer 1 and the sealant layer 2 is wide.

The base film layer 1 has at least a surface layer made of polyethylene terephthalate (PET). In the example shown in FIG. 3, the base film layer 1 has a single-layer (PET layer) structure made of stretched PET.

The base film layer 1 is made of stretched PET because the transparency of PET is good.
In addition, since it has low moisture absorption and water absorption, it is most suitable for use in the base film layer 1 of the food packaging film F. That is, the article to be packaged M filled in the packaging bag H may be filled in a heated state.
Such packaged articles M often contain a considerable amount of water,
Furthermore, since the heat treatment or freezing treatment, such as boil sterilization, is performed on the packaging bag H filled with the article to be packaged M as necessary, the base film layer 1 is exposed to such an environment. This is because it is optimal to use PET which is hardly deteriorated. When PET, which is hardly deteriorated even in such an environment, is used for the base film layer 1, high dimensional stability of the base film layer 1 can be ensured, so that color misregistration hardly occurs in multicolor gravure printing on the packaging film F. In addition, it is possible to appropriately perform automatic bag making, filling and packaging by photoelectric control.

Other plastic materials generally usable as the base film layer 1 include cellophane, polypropylene (PP) and nylon (NY). Cellophane and NY are more water-absorbing than PET. Is high. (PET has a water absorption of 0.1% or less, NY has a water absorption of 9%, and cellophane has a water absorption of 40 to 100%.)
PP is prone to thermal contraction.

The base film layer 1 may be constructed such that one or more intermediate layers such as an aluminum layer and a SiOx layer are provided between the PET layer and a sealant layer 2 described later. When such an aluminum layer or the like is provided, it is possible to enhance the gas barrier properties, the moisture-proof property, the ultraviolet light transmission-preventing property, and the like of the packaging film F.

The sealant layer 2 has a polyethylene layer 2a (PE layer) and a crystalline polypropylene layer 2b (crystalline PP layer) from the side of adhesion to the base film layer 1 from the side opposite to the adhesion side. ) And the non-crystalline polypropylene layer 2c (non-crystalline PP layer).

Such a sealant layer 2 can be obtained by forming these three layers by co-extrusion, forming them by a multilayer method, and forming them without stretching. An adhesive resin layer 2d is interposed between the PE layer 2a and the crystalline PP layer 2b.

The reason why the sealant layer 2 is formed without stretching is because the stretched film changes its molecular structure due to stretching, so that the heat sealing property is deteriorated.

The non-crystalline PP layer 2c is used on the side opposite to the side bonded to the base film layer 1, that is, on the side inside the packaging bag H, as follows.
This is because the heat melting temperature is higher than PE, but lower than the crystalline PP, and the temperature range in which proper heat sealing can be performed is wide. Therefore, the packing bag H can be easily formed at a high speed by the filling and packing machine as described above. (The thermal melting temperature of amorphous PP is
Generally, 130 ° C to 150 ° C)

The melting temperature of the crystalline PP layer 2b is non-crystalline P
Generally higher than the melting temperature of the P layer 2c. As a result, the crystalline PP layer 2b between the PE layer 2a and the non-crystalline PP layer 2c is subjected to a heat treatment such as a boil sterilization or a freezing treatment of the packaged material M filled in the packaging bag H. Is hardly deteriorated, and high durability of the packaging film F with respect to a temperature change can be secured. Also, this crystalline PP layer 2b
Thereby, a suitable rigidity can be given to the packaging film F.

The non-crystalline PP layer 2c and the crystalline PP layer 2b are well adapted to each other when formed by the co-extrusion multilayer method, and do not cause separation between the two layers.

Typically, the heat seal temperature for forming the first and second heat seals 8 and 9 is 130 ° C. to 1 ° C.
When the temperature is 50 ° C., the melting temperature of the amorphous PP layer 2 c is 1
The sealant layer 2 is formed at a temperature of 30 ° C. to 150 ° C. and a melting temperature of the crystalline PP layer 2b of 160 ° C. to 200 ° C.

Typically, when the total thickness of the packaging film F is 62 to 95 μm, the base film layer 1
Is 12 to 25 μm, the sealant layer 2 is 50 to 70 μm, and the PE layer 2 a
Is 10 to 15 μm, and the crystalline PP layer 2b is 30 to 40 μm.
m, the non-crystalline PP layer 2c has a thickness of 10 to 15 μm.

Pulling both sides 4 and 4 of the packaging bag H at the portions where the first and second heat seals 8 and 9 have been applied in a direction to separate both sides 4 and 4 of the packaging bag H. The following three types are prepared as packaging films F constituting the packaging bag H so that they can be separated from each other, and a test of the heat seal strength specified in 7.5 of JIS standard number Z1707 is performed. went.

(1) Experimental Example The PE layer 2a and the crystalline PP were formed by moving the sealant layer 2 from the side of adhesion to the base film layer 1 to the side opposite to the side of adhesion.
A packaging film F in which three layers of a layer 2b and an amorphous PP layer 2c are laminated in this order, and the thickness of the sealant layer 2 is 60 μm. (2) Comparative Example 1 Adhesion of the sealant layer 2 to the base film layer 1 From the side to the side opposite to the adhesive side, the first PE layer, the second P layer
A packaging film F in which three layers of an E layer and a crystalline PP layer are laminated in this order, and the thickness of the sealant layer 2 is 30 μm. (3) Comparative Example 2 The sealant layer 2 is bonded to the base film layer 1 from the adhesive side. The first PE layer and the second P
E, an ethylene-vinyl acetate copolymer layer in which three layers are laminated in this order, and the thickness of the sealant layer 2 is 30 μm.

The results are shown in the following table.

[0051]

[Table 1]

It was recognized that the heat seal strength of the experimental example was the weakest. The first and second heat seals 8, 9 are pulled by pulling the two sides 4, 4 of the packaging bag H in a direction to separate them.
The heat seal strength at which the surfaces 4 and 4 can be easily separated from each other in the portion provided with is 10 N / 15 mm width or less,
Comparative Examples 1 and 2 were found to be unsuitable for use as the packaging film F constituting the packaging bag H.

[0053]

According to the food packaging film of the present invention, food can be packaged by three-sided seal packaging or four-sided seal packaging without any inconvenience, and both sides of the packaging bag can be easily sealed at the heat-sealed portion. In addition, the food that has been appropriately separated and packaged can be smoothly taken out without cutting the packaging bag.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a filling and packaging machine.

FIG. 2 is a schematic configuration diagram of a filling and packaging machine.

FIG. 3 is an enlarged configuration diagram showing a state in which the heat sealing portion 3 of the packaging bag H has begun to be interfacially separated.

FIG. 4 is a perspective view showing an example of a packaging bag H.

FIG. 5 is a sectional view taken along line AA in FIG. 4;

6 is a perspective view showing a state in which the heat seal portion 3 of the packaging bag H shown in FIG.

FIG. 7 is a perspective view showing an example of the packaging bag H shown in FIGS. 4 to 6 which differs from the packaging bag H shown in FIGS.

[Explanation of symbols]

 x Transport direction F Packaging film M Packaged material H Packaging bag 1 Base film layer 1a Adhesive 2 Sealant layer 2a Polyethylene layer 2b Crystalline polypropylene layer 2c Amorphous polypropylene layer 4 Both sides 8 First heat seal 9 Second heat sticker

Front page of the continued F-term (reference) 3E064 AA04 AA05 BA26 BA30 BA55 BB03 BC01 BC02 BC03 BC18 EA30 FA03 GA01 HN06 3E086 AA02 AB01 AD01 BA04 BA15 CA01 4F100 AK04B AK07C AK07D AK42A BA04 BA07 BA10A BA10D CB00 DA02 EJ37A GB17 GB23 JA11C JA12D JL12 JL12B JL12C JL12D JL14 JL14C JL14D

Claims (1)

[Claims] 1. A first heat seal continuously applied in a direction along a film transport direction, and a second heat seal applied at intervals in a direction crossing the transport direction. A packaging film for forming a three-side sealed packaging bag or a four-side sealed packaging bag formed successively while filling an object to be packaged, wherein the packaging film is stretched on the side outside the packaging bag. The layer has a non-stretched sealant layer laminated to the base film layer via an adhesive on the side inside the packaging bag, and the base film layer has a surface layer composed of at least polyethylene terephthalate. Along with, the sealant layer is a polyethylene layer from an adhesive side to the base film layer to a side opposite to the adhesive side,
A crystalline polypropylene layer and a non-crystalline polypropylene layer are formed by laminating these three layers in this order, and the first and second heat seals are formed by pulling in a direction in which both sides of the packaging bag are separated. Interfacial separation occurs between the non-crystalline polypropylene layer on one side of the packaging bag and the non-crystalline polypropylene layer on the other side of the packaging bag that are welded to each other at the applied portion. A food packaging film, characterized in that: