Packaging bag

Abstract

To provide a packaging bag formed with a laminated film containing an aluminum layer, the packaging bag being capable of suppressing occurrence of a small crack in the aluminum layer in a vicinity of an inner edge of a seal portion.SOLUTION: A rectangle packaging bag formed with laminated film containing an aluminum layer and having at least three end edges sealed to form a storage part includes a weakened line in the storage part away from the sealed portion in plan view at which strength of the laminated film is weakened and a notch that is formed in at least one of the three end edges and triggers breakage of the laminated film when the storage part is opened. The weakened line is formed in a direction orthogonal to the end edge in which the notch is formed and on a straight line elongating from the notch to an end edge opposite to the end edge at which the notch is formed.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a packaging bag. [Background technology]

[0002] Known packaging bags include three-sided sealed bags made by folding a sheet of rectangular laminated film in half and sealing the joined edges to form a storage section, and four-sided sealed bags made by overlapping a set of rectangular laminated films on top of each other and then sealing (heat sealing) the edges to form a storage section.

[0003] Patent Document 1 discloses a rectangular packaging bag (four-sided sealed bag) in which weakened lines (lines to be opened) extending parallel to each other along two of the four edges of the bag are formed on the front and back laminated films by half-cutting or the like to reduce the strength of the bag. This packaging bag can be used to package sheet-like contents such as a tape or patch for transdermal administration of a drug.

[0004] A user of this packaging bag first starts from a notch (cutout) formed on one edge of the packaging bag and tears the laminate film along the weakened line near the notch to the opposite end. Next, a user of the packaging bag starts from a notch formed on another edge of the packaging bag and tears the laminate film along the weakened line near the notch to the opposite end. As a result, an opening is formed in the packaging bag that is composed of a tear line formed along the two weakened lines. This opens the opening wide, allowing a user of the packaging bag to easily remove the contents from the opening. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] International Publication No. 2015 / 105101 Summary of the Invention [Problem to be solved by the invention]

[0006] In such a packaging bag, when sealing the edge, since the laminated film is pressed by the seal bar, a tensile load is likely to be generated in the laminated film at the inner edge of the seal portion. In particular, when forming the seal portion in a state where a hard and thick content is accommodated, the laminated film at the inner edge of the seal portion is pressed in a state of being expanded in the thickness direction of the packaging bag, so that a larger tensile load is likely to be generated.

[0007] Here, in a packaging bag in which the laminated film contains an aluminum layer, a weakening line may be formed from the seal portion to the accommodating portion to facilitate opening. In such a packaging bag, the weakening line is constituted by thinning the outermost layer. For this reason, when stress is concentrated on the aluminum layer around the weakening line near the inner edge of the seal portion during the sealing process, distribution, or storage after sealing, minute cracks (ruptures) may occur, and the barrier performance of the packaging bag may be lost.

[0008] The present invention has been made in view of such problems, and an object thereof is to suppress the occurrence of minute cracks in the aluminum layer near the inner edge of the seal portion in a packaging bag formed using a laminated film containing an aluminum layer.

Means for Solving the Problems

[0009] One aspect of the present invention for solving the above problems is a rectangular packaging bag formed by overlapping laminated films containing an aluminum layer and sealing at least three edges to form an accommodating portion, and a first edge which is one of the three edges and first notches and second notches formed at respective ones of the fourth edges each of which is an edge adjacent to the first edge and serves as a trigger for breaking the laminated film when opening the accommodating portion, and the first notches From the first edge, through the accommodating portion, to the second edge facing the first edge in a direction orthogonal to the first edge Formed on a virtual first straight line extending are formed of perforations constituted by intermittent cuts A first weakening line that linearly weakens the strength of the laminated film, and the second notches From the first edge, through the accommodating portion, to the third edge facing the fourth edge in a direction orthogonal to the fourth edge Formed on a virtual second straight line extending are formed of perforations constituted by intermittent cuts, and a second weakening line that linearly weakens the strength of the laminated film, and in a plan view, the distance between one end of the first weakening line and the inner edge of the seal portion formed by sealing the first edge, the distance between the other end of the first weakening line and the inner edge of the seal portion formed by sealing the second edge, and the A packaging bag in which the distances between one end of the two weakening lines and the inner edges of the seal portions formed by sealing the fourth edge are all 1 mm or more and 5 mm or less.

Advantages of the Invention

[0010] According to the present invention, in a packaging bag formed using a laminated film containing an aluminum layer, the generation of microcracks in the aluminum layer near the inner edge of the seal portion can be suppressed.

Brief Description of the Drawings

[0011]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Modes for Carrying Out the Invention

[0012] The packaging bag according to the embodiment of the present invention will be described with reference to the drawings. In the modifications and the like, the same or corresponding components are denoted by the same reference numerals and the description thereof is omitted.

[0013] FIG. 1 shows a plan view and a side view of a packaging bag 100 according to an embodiment of the present invention. The packaging bag 100 is a four-side seal packaging bag including a storage portion 30 surrounded by a seal portion 20 formed by overlapping two rectangular films 10 and sealing four edges 71 to 74. The packaging bag 100 further includes a first weakening line 41 and a second weakening line 42 formed at least on the storage portion 30 to weaken the strength of the film 10, and a first notch 51 and a second notch 52 formed at any two of the edges 71 to 74, which serve as a trigger for film 10 breakage when opening the storage portion 30.

[0014] Hereinafter, the edge where the first notch 51 is formed is referred to as the first edge 71, the edge opposite to the first edge 71 is referred to as the second edge 72, the edge adjacent to the first edge 71 and closer to the first notch 51 among the adjacent edges is referred to as the third edge 73, and the edge opposite to the third edge 73 is referred to as the fourth edge 74.

[0015] (Film) The film 10 is formed in a rectangular shape and can be made into the packaging bag 100 having the storage portion 30 by sealing the edges 71 to 74. The film 10 is a multilayer film including an aluminum layer. A sealant layer can be used for the innermost layer of the film 10 to seal the edges 71 to 74 by heat sealing or the like. As materials for other layers constituting the film 10, for example, polyethylene terephthalate (PET), aluminum (AL), cellophane, polyethylene (PE), transparent vapor-deposited PET, low-adsorption sealant (PET having heat-sealability, cyclic polyolefin, EVOH sealant, etc.) can be used, and these can be used in appropriate combinations.

[0016] (Notch) The first notch 51 and the second notch 52 are incisions formed on the edges 71 to 74 of the packaging bag 100. When opening the storage part 30, the user of the packaging bag 100 can break the film 10 starting from the first notch 51 and the second notch 52. As shown in FIG. 1, the packaging bag 100 includes a first notch 51 formed on the first edge 71 and a second notch 52 formed on the fourth edge 74. Both the first notch 51 and the second notch 52 are formed by linearly cutting the seal part 20 over a predetermined length toward the opposing edges 71 to 74. The shapes of the first notch 51 and the second notch 52 are not limited to linear shapes as long as they can serve as a trigger for breaking the film 10, and notch shapes such as triangles and pentagons can be adopted.

[0017] (Weakening line) The first weakening line 41 and the second weakening line 42 are locations where the strength of the film 10 is weakened linearly. The first weakening line 41 can guide the breaking line starting from the first notch 51 to the vicinity of the seal part 20 on the second edge 72, which is the edge opposite the first edge 71. Also, the second weakening line 42 can guide the breaking line starting from the second notch 52 to the vicinity of the seal part 20 on the third edge 73, which is the edge opposite the fourth edge 74.

[0018] In the packaging bag 100, the first weakening line 41 and the second weakening line 42 are formed on both of the two films 10 so as to overlap in a plan view when formed on the packaging bag 100, but they may be formed on only one of the two films 10.

[0019] As shown in FIG. 1, the first weakening line 41 and the second weakening line 42 are formed on the storage part 30 in a plan view, away from the seal part 20. Also, the first weakening line 41 and the second weakening line 42 are formed on a virtual straight line (not shown) extending in a direction orthogonal to the first edge 71 or the fourth edge 74 from the first notch 51 and the second notch 52.

[0020] FIG. 2 shows an enlarged view of the packaging bag 100 for explaining the formation position of the weakened line, taking the first weakened line 41 as an example. The distance La between the end of the first weakened line 41 and the inner edge 21 of the seal portion is preferably larger, specifically, preferably 1 mm or more. By setting the distance La to 1 mm or more, the first weakened line 41 is not formed near the inner edge 21 of the seal portion, so that the concentration of stress on the aluminum layer near the inner edge 21 of the seal portion can be prevented. As a result, the generation of microcracks in the aluminum layer near the inner edge 21 of the seal portion can be suppressed.

[0021] The first weakened line 41 and the second weakened line 42 can be obtained by forming intermittent linear cuts (half cuts) in the film 10. Specifically, the first weakened line 41 and the second weakened line 42 can be formed by providing cuts penetrating only the outermost layer of the laminated film. For the formation of the first weakened line 41 and the second weakened line 42, well-known methods such as a method using a blade type such as a Thomson blade or a leather blade, or a method using a carbon dioxide laser can be used.

[0022] (Modification example) The first weakened line 41 and the second weakened line 42 may be curved instead of straight. FIG. 3 shows a packaging bag 101 according to a modification example in which the first weakened line 41 and the second weakened line 42 are formed as curves.

[0023] The shape of the first weakened line 41 and the second weakened line 42 is not limited to the perforations formed by intermittent cuts as long as the strength of the film 10 can be weakened linearly. FIG. 4 shows a packaging bag 102 according to a modification example in which the shape of the first weakened line 41 and the second weakened line 42 is formed by arranging two straight lines each formed by intermittently forming linear half cuts. Further, FIG. 5 shows a packaging bag 103 according to a modification example in which the shape of the first weakened line 41 and the second weakened line 42 is formed as a figure-eight perforation in which a plurality of sets of two fine cuts in a figure-eight shape are arranged linearly. In addition to these, shapes such as a straight line or a multiple line formed by arranging a plurality of straight lines can be used for the first weakened line 41 and the second weakened line 42.

[0024] The packaging bag 100 is a four-side sealed bag, but the packaging bag is not limited to a four-side sealed bag as long as it is a rectangular packaging bag that seals at least three edges to form a storage part. As the packaging bag, for example, a three-side sealed bag formed by folding a single rectangular laminated film in half and sealing the joined edges may be used. Also, a four-side sealed bag formed by folding a single rectangular laminated film in half and having four edges may be used.

[0025] One first weakening line 41 and one second weakening line 42 were formed on the packaging bag 100, but only one of the weakening lines may be used.

Example

[0026] Packaging bags according to the examples and comparative examples were manufactured, and an evaluation was made on the presence or absence of the generation of microcracks in the aluminum layer of each packaging bag. The packaging bags according to the examples were manufactured by changing the formation position (interval La) and the shape of the weakening lines of the packaging bag 100 shown in FIG. 1. The packaging bags according to the comparative examples were formed such that the weakening lines of the packaging bag 100 were in contact with the seal part. In both the examples and the comparative examples, similar to the packaging bag 100, two weakening lines were formed so as to be symmetric with respect to the diagonal line starting from the corner where the two edges each having two notches formed thereon were in contact (the first and second weakening lines).

[0027] As the packaging bags according to all the examples and comparative examples, those using films having the following layer structures in order from the outermost layer to the innermost layer were all created respectively. (1) Polyethylene terephthalate (PET) (12 μm) / Aluminum (AL) (7 μm) / PET having heat sealability (20 - 50 μm) (2) Cellophane (#300 - 500) / AL (7 μm) / PET having heat sealability (20 - 50 μm) (3) PET (12 μm) / AL (9 μm) / Polyethylene (PE) (20 - 50 μm) (4) PET (12 μm) / PE (10 - 30 μm) / AL (7 μm) / PE (10 - 40 μm) (5) Cellophane (#300 - 500) / PE (10 - 30μm) / AL (7μm) / PE (10 - 40μm)

[0028] After cutting the above film into a rectangular shape corresponding to the dimensions of the packaging bag described later, a weakening line was formed on the film surface. Then, two films with the weakening line formed were prepared, and after overlapping them so that their innermost layers (sealing layers) faced each other, the previously prepared contents were placed in the accommodating part and the four edges were heat-sealed. The seal width (Ls in Figure 2) was set to 5 mm. Finally, linear notches were formed in the seal part to obtain a packaging bag. The notches were formed at a position where the distance (Ln in Figure 2) from the corner of the packaging bag where adjacent edges contact each other was 10 mm. As the contents to be placed in the packaging bag, a tape agent with dimensions 30 mm smaller than the dimensions of each packaging bag in both the left - right and up - down directions and a thickness of 5 mm was used.

[0029] Table 1 shows the dimensions of each packaging bag according to Examples 1 - 14 and Comparative Examples 1 - 11, the distances La between both ends of the first and second weakening lines and the inner edge of the seal part, the shape of the weakening line, and the evaluation results (presence or absence of cracks in the aluminum layer). When the distance La is a positive value, it indicates a state where the weakening line is separated from the seal part in a plan view, and when the value is negative, it indicates a state where the weakening line is formed on the seal part.

[0030]

Table 1

[0031] For the packaging bags according to Examples 1 - 14, each of the first and second weakening lines was formed at a distance of 1 mm or more from the inner edge of the seal part. Therefore, the stress generated in the aluminum layer near the inner edge of the seal part due to sealing could be reduced, and as shown in Table 1, no micro - cracks occurred in all samples. Thus, it was confirmed that by forming the weakening line away from the seal part, micro - cracks in the aluminum layer near the inner edge of the seal part can be suppressed.

[0032] In contrast, for the packaging bags according to Comparative Examples 1 to 11, the weakening lines were in contact with the seal portion or formed on the seal portion. Therefore, a large stress was generated in the aluminum layer near the inner edge of the seal portion during sealing, and as shown in Table 1, microcracks occurred in all samples.

Industrial Applicability

[0033] The present invention can be suitably used for packaging sheet-like contents such as tape materials and patches for transdermal administration of drugs.

Explanation of Reference Numerals

[0034] 100 to 103 Packaging bag 10 Film 20 Seal portion 21 Inner edge of the seal portion 30 Accommodation portion 41 First weakening line 42 Second weakening line 51 First notch 52 Second notch 71 First edge 72 Second edge 73 Third edge 74 Fourth edge

Claims

【Claim 1】 A rectangular packaging bag formed by overlapping laminated films containing an aluminum layer and sealing at least three edges to form a storage portion, A first notch and a second notch formed respectively at one edge of the three edges, which is the first edge, and one edge adjacent to the first edge, which is the fourth edge, and serving as a trigger for breaking the laminated film when opening the storage portion; A first weakening line formed on a virtual first straight line extending in a direction perpendicular to the first edge from the first notch to the second edge facing the first edge through the storage portion, consisting of intermittent cuts in the form of perforations, and linearly weakening the strength of the laminated film; A second weakening line formed on a virtual second straight line extending in a direction perpendicular to the fourth edge from the second notch to the third edge facing the fourth edge through the storage portion, consisting of intermittent cuts in the form of perforations, and linearly weakening the strength of the laminated film, and comprising: A packaging bag in which the distance between one end of the first weakening line and the inner edge of the seal portion formed by sealing the first edge, the distance between the other end of the first weakening line and the inner edge of the seal portion formed by sealing the second edge, and the distance between one end of the second weakening line and the inner edge of the seal portion formed by sealing the fourth edge are all 1 mm or more and 5 mm or less in a plan view.

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