JP2001114296A - Bag - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the fall strength of a bag. SOLUTION: A two-folded bottom film is put between obverse and reverse films and the inside face of the obverse and reverse films and the inside face of the bottom film are adhered in a range except a specified range along a fold of the bottom film to form a bottom seal part and the mutual inside faces of the obverse and reverse films are adhered to form a side seal part. The intersection of the bottom seal part which crosses the fold of the bottom film is set in the inner side of the bag than the side seal part.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a bag.

[0002]

2. Description of the Related Art As a bag for accommodating a liquid or powder, as shown in FIG. 3, a bottom film 3 folded in two is sandwiched between front and back films 1 and 2, and inner surfaces of the front and back films 1 and 2 and a bottom film are formed. 3 is bonded to the inner surface of the bottom film 3 in a range excluding a certain range (the bottom forming portion 4) along the fold 3A of the bottom film 3 to form the bottom seal portion 5, and the inner surfaces of the front and back films 1 and 2 are bonded together. Side seal portion 6.

[0003]

In the prior art, the intersection P of the bottom seal 5 intersecting the fold 3A of the bottom film 3 is known.
Are also intersected with the side seal portion 6. For this reason,
When the bag is dropped, the drop impact force F acting on the bottom forming portion 4 immediately reaches point P. This point P is included in the side seal portion 6 and has high rigidity and is hardly bent, so that the pin is damaged and damaged. There is a possibility that a hole is generated. For this reason, it is difficult to select a constituent material, for example, the thickness of the constituent film of the bag cannot be reduced.

An object of the present invention is to improve the drop strength of a bag.

[0005]

According to the first aspect of the present invention, a two-folded bottom film is sandwiched between front and back films, and the inner surface of the front and back films and the inner surface of the bottom film are creased on the bottom film. A bag formed by adhering a part except a certain range along the part to form a bottom seal part and adhering the inner surfaces of the front and back films to form a side seal part, intersecting the fold part of the bottom film. The intersection of the bottom seal part to be set was set inside the bag from the side seal part.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in FIG. 1, a bag 10 has a bottom film 1 folded in two between front and back films 11 and 12. As shown in FIG.
3, the inner surfaces of the front and back films 11 and 12 and the inner surface of the bottom film 13 are adhered to each other in a range excluding a certain range (bottom forming portion 14) along the fold portion 13A of the bottom film 13 to form a bottom seal portion 15 And the front and back films 11, 1
2 are adhered to each other to form a side seal portion 16.

FIG. 2 shows a manufacturing procedure of the bag 10 by the bag making machine, in which a long bottom film 13 is inserted between the long front and back films 11 and 12, And a step of continuously forming the bottom seal portion 15 and the side seal portion 16 of each other, and a process of cutting out the side seal portions 16 of the adjacent bags 10 to take out each one bag 10.

However, in the bag 10 of FIG. 1, when forming the bottom seal portion 15 and the side seal portion 16, the intersection R of the bottom seal portion 15 intersecting the fold portion 13A of the bottom film 13 is determined by the side seal portion. The length L is spaced apart from the inside of the bag by a length L.

Thus, according to the present embodiment, the following operations are provided. That is, when the bag 10 is dropped, the drop impact force F acting on the bottom forming portion 14 is equal to the fold 13 of the bottom film 13.
A is adhered to the front and back films 11 and 12 and is alleviated by bending of the portion L forming the bottom seal portion 15, and then the side seal portion 1 at which the fold portion 13A intersects.
6 at the intersection P. Although the point P has high rigidity, the force Fa acting on the point P has already been reduced, and it is unlikely to cause breakage. For this reason, selection of a constituent material becomes easy, for example, the constituent film of the bag 10 can be thinned.

The constituent materials of the front and back films 11, 12 and the bottom film 13 are as follows. That is, both the front and back films 11, 12 and the bottom film 13 are formed by laminating an outer layer film and an inner layer film with a laminating adhesive. The outer layer film is a resin film having heat resistance, and is preferably, for example, (biaxially) stretched polyethylene terephthalate, (biaxially) stretched nylon or (biaxially) stretched polypropylene. Further, the inner layer film is a resin film having a high sealing property with respect to a filler such as a liquid or a powder and having a heat-sealing property. For example, low-density polyethylene and medium-density polyethylene are preferable.

[0011]

As described above, according to the present invention, the drop strength of the bag can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic view showing a bag.

FIG. 2 is a schematic view showing a procedure for manufacturing a bag.

FIG. 3 is a schematic diagram showing a conventional example.

[Explanation of symbols]

 Reference Signs List 10 bags 11, 12 Front and back films 13 Bottom film 13A Folded part 15 Bottom seal part 16 Side seal part

Claims (1)

[Claims] 1. A bottom seal in which a folded bottom film is sandwiched between front and back films, and an inner surface of the front and back films and an inner surface of the bottom film are adhered to each other in a range excluding a certain range along a fold portion of the bottom film. A bag formed by bonding the inner surfaces of the front and back films together to form a side seal portion, wherein the intersection of the bottom seal portion crossing the fold portion of the bottom film is
A bag set inside the bag from the side seal.