JP3292527B2 - Bag body for bag-in-box and method of manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a bag-in-box (Bag-in-box).
In Box), a foldable rectangular bag-in-box consisting of sheet-like members
Related to a bag.

[0002]

2. Description of the Related Art Bag-in-boxes, which are disposable so-called one-way containers, have been widely used for transporting and storing various liquids such as beverages such as mineral water and industrial chemicals.

[0003] This bag-in-box uses a foldable bag or container made of plastic for the interior and a corrugated cardboard box on the interior, and is provided with water resistance, chemical resistance, gas barrier property and the like to the contents liquid. The structure is such that the rigidity required for transportation and storage is provided to the exterior while the plastic is provided. Compared to conventional glass bottles, tin cans, etc., the bag-in-box constructed in this way does not require collection, which contributes to labor saving and cost saving, and is easy to transport and store empty containers because it can be folded. This has the advantage that the distribution cost can be reduced.

As a bag for a bag-in-box used for the interior of the bag-in-box, a molded container formed by blow molding or a flat bag formed by a heat sealing method has been widely used.

[0005]

However, in the case of the blow-molded container described above, if the thickness of the container material is generally not sufficient, the strength of the container is insufficient, so that it is necessary to increase the thickness. There is a problem in that the bag is hard to be crushed, becomes bulky, and the transportation and storage of empty bags and the disposal process become inconvenient. Further, since the mold used for molding is expensive, it becomes a standard container, and there is also a problem that it is difficult to meet various requirements. Furthermore, in order to fill the contents, there is a drawback in that it is necessary to blow air into the empty bag beforehand to adjust the shape. Furthermore, polyethylene or polypropylene is generally used as a material for forming such a blow-molded container, but these materials have a drawback that it is difficult to ensure barrier properties.

On the other hand, in the flat bag by the heat sealing method, a residue is generated inside the bag when the contents liquid is extracted,
There is a problem that the content liquid cannot be completely extracted. Further, when the cardboard box is exteriorly formed from the shape, a gap is formed in a corner inside the cardboard box, so that there is a problem that the burden of the strength and the drop strength when the bag-in-box is stacked is applied to the cardboard box. In addition, there is a lot of waste when the content liquid is filled due to the shape of the flat bag.
There is a drawback that the used packaging material area of a 0-liter flat bag is required to be about 40% larger than the used packaging material area when the shape of the bag is square.

The present invention has been made in view of the above circumstances, and an object of the present invention is to solve various problems of the conventional bag-in-box bag, to transport and store empty bags, and to dispose of them. It is not necessary to blow air into the empty bag before filling the content liquid, and it is easy to meet various demands. A bag-in-box that has the features of being able to completely extract the contents of liquid without generating any residue, and having strength higher than that of a single cardboard box and excellent stability in stacking or transportation. It is an object of the present invention to provide a method for manufacturing a bag for a bag-in-box capable of efficiently obtaining a bag for a bag and a bag-in-box having such advantages.

[0008]

In order to solve the above-mentioned problems, the structure of the present invention is formed so as to include a pair of opposed flat portions and a folding line each of which is folded inward in a fold shape. A bag body for a bag-in-box comprising a cylindrical bag main body including a pair of opposed side surfaces, and a pair of mouth sealing sheets respectively sealing mouths at both ends of the bag main body. , The bag main body portion has an injection spout in one of the pair of flat portions, and the bag
The main body is folded in order to open the mouths at both ends.
Any two points on the line are used as base points, and each of these base points
From the first fold line to the end of each mouth, the original fold direction
Fold it in reverse and pull out the side part,
Lines connecting the four corners of the body to each base point
Opening formed to be folded as a convex ridgeline
Surfaces are formed at the mouths at both ends, and the pair of flat portions and the pair of side portions are heat-sealed at the peripheral edges, and the pair of mouth sealing sheets are folded inward in a fold shape, respectively. For the bag-in-box, characterized in that these opening sealing sheets are formed so as to be foldable by being heat-sealed at respective open surfaces and peripheral edges of the bag main body. A bag, wherein the opening surface is substantially the same
It may be formed so as to be a surface, a cylindrical shape comprising a pair of opposed flat portions and a pair of opposed side portions formed so as to have folding lines each folded inward in a fold shape. Production of a bag body for a bag-in-box, comprising: a bag main body part; and a pair of mouth sealing sheets each sealing the mouths at both ends of the bag main body and being folded inward in a folded manner. A method of forming a tubular bag body by heat-sealing the pair of flat portions and the pair of side portions at peripheral edges thereof, and a tubular shape obtained in the bag body forming process. Forming four cut corners by cutting four corners of each mouth portion of the bag body, and using any arbitrary point in the folding line of each of the pair of side surfaces to open each mouth portion as a base point, Fold the first fold line from to the end of each mouth in the opposite direction to the original fold direction. A step of forming each open surface in which the inside of the bag is exposed by folding and folding the bag so as to be drawn out and folding a line connecting the cut corner of the bag body to the base point as a ridgeline that is convex in the inward direction of the bag. A step of placing a square-shaped mouth sealing sheet on the opening surface, and a step of thermally fusing each edge of each of the placed mouth sealing sheets, for a bag-in-box, It is a manufacturing method of a bag.

[0009]

The bag body for a bag-in-box according to the present invention comprises a tube comprising a pair of opposed flat portions and a pair of opposed side portions formed so as to have a folding line which is folded inward in a folded manner. A bag body, and a pair of mouth sealing sheets respectively sealing the mouths at both ends of the bag body. The bag body is injected into one of the pair of flat portions. A pair of mouth sealing sheets each having an outlet and having a pair of flat portions and a pair of side portions that are heat-sealed at the peripheral edges, and each having a folding line that is folded inward in a fold shape, respectively. The portion and the periphery are heat-fused to be foldable. Therefore, in this bag-in-box bag body, it is possible to compactly fold along the fold lines formed on the pair of side surfaces and the fold lines formed on the pair of mouth sealing sheets, respectively. Yes, this enables efficient transport / storage in an empty bag state as well as efficient disposal. In addition, since the shape is square, there is no gap at the corner of the cardboard box when the cardboard box is exteriorized, and the strength and drop strength when stacking the bag-in-box are higher than when using the cardboard box alone. Not only is it improved, but it is not necessary to blow air before filling the content liquid. In addition, by laminating the barrier layer on the forming material of each pair of the flat part and the side part and the opening sealing sheet, it is possible to easily secure the barrier property.

On the other hand, according to the manufacturing method of the present invention, a pair of flat portions and a pair of side portions each having a folding line which is folded inward in a fold shape are heat-sealed at their peripheral edges to form a cylindrical shape. Forming the bag body, forming an open surface in which the inner surface of the bag is exposed by bending and pulling out the folding line of each side from the opening end of the bag body in the opposite direction to the original folding direction, Since the mouth sealing sheets each formed with a fold line that is folded inward into a fold shape are placed on the open surfaces and the peripheral edges of the sheets are heat-sealed, the empty space is formed. It is possible to fold it compactly in a bag state, and it is possible to efficiently carry out transport, storage, and disposal processing, and because it is a square shape, when a cardboard box is packaged, the strength is improved beyond the strength of the cardboard box alone. Bag in box with features The use bag body can be efficiently obtained.

[0011]

EXAMPLES Next, examples of the present invention will be shown, and the present invention will be described more specifically. As shown in FIG. 1, the bag body for a bag-in-box of the present invention is formed so as to include a pair of opposed flat portions 11, 11 and a folding line 21 each of which is folded inward in a folded manner. And a pair of flat surface portions 1
Injection spout 2 formed in any one of 1 and 11
The bag body 10 includes a cylindrical bag body 10 having a plurality of openings 5 and a pair of mouth sealing sheets 31 for sealing the mouths 10a and 10b at both ends of the bag body 10, respectively. In this embodiment, the injection pouring port 25 is formed by attaching an injection / pouring member made of plastics to an injection / pouring member mounting hole provided in one of the flat portions 11.

As shown in FIG. 2, the bag body 10 is
In order to open the mouths 10a and 10b at both ends once,
An open surface formed by bending each fold line 21 formed on each of the two side portions 22 and 22 outward from the open end in a direction opposite to the original fold direction. Are formed so as to form a heat-sealed portion over the entire periphery thereof.

Further, a pair of opposing flat portions 11 and 11 and a pair of opposing side portions 2 constituting the bag body 10 are formed.
Normally, the pair of mouth-sealing sheets 31, 31 are formed of the same material. Examples of the forming material include a resin material or a resin laminate material obtained by laminating a resin and a metal foil, paper, or the like. For example, if a resin laminate material having a barrier layer such as an aluminum foil is used, the barrier properties of the bag-in-box bag can be easily secured.

The bag-in-box having such a configuration becomes clearer by describing the following manufacturing steps. First, as shown in FIG. 3, two side surface portions 2 formed so as to include a pair of opposing flat portions 11 and 11 and fold lines 21 and 21 folded inward in a fold shape.
A cylindrical bag main body 10 having 2, 22 is prepared. The cylindrical bag main body 10 is formed by bonding a flat portion forming material that forms the flat portions 11 and a side portion forming material that forms the side portions 22 and 22.

Next, as shown in FIG. 4, the bag body 10 is cut inward to a predetermined depth from the upper end of the joint between the flat portions 11, 11 and the side portions 22, 22, respectively. Cut into the two mouths, corners 15,15,
15 and 15 are formed. The cuts at this time have substantially the same depth. This cutting is particularly effective for facilitating the bag making operation and for adjusting the product shape by the cutting operation described later.

Thereafter, as further shown in FIG. 4, the two side portions 22, 22 are opened to open the mouth of the bag body 10.
Of the fold lines 21 and 21 from the arbitrary points P and P, respectively, and the fold lines 21 and 21 from the base points P and P to the ends H and H of the fold lines are opposite to the original fold direction. It is folded and pulled out so as to be the reverse folds 21a, 21a. By this folding, the four corners of the mouth (in this case, the cut corners 15, 15, 15, 15 are formed at the four corners, so the ends D of these cut corners) are moved from the base points P, P The lines connecting the two sides are formed as four ridge lines 17 protruding inside the bag, thereby forming an open surface in which the inside of the bag is exposed. In this embodiment, this open surface is
Due to the combination with the mouth sealing sheet 31, the shape is not completely opened, and a constant folding angle θ1 within 180 degrees is maintained. However, in some cases, for example, as shown in FIG. 2, it is also possible to completely open the opening so that the opening surfaces are substantially the same plane.

The position above such an open surface is shown in FIG.
As shown in (2), the mouth sealing sheet 31 having the folding line 35 at the center is conveyed. A folding angle θ2 is formed by the folding line 35, and the folding angle θ2 is
0 is substantially the same as the folding angle θ1. In the present embodiment, the size of the mouth sealing sheet 31 is the opening surface 11a,
Although the size is approximately the same as the size formed by the four edges 11a, the size may be larger than the size formed by the four edges. In addition, in FIG.
Although only the mouth sealing sheet 31 for sealing is shown,
Regarding the mouth sealing sheet 31 for sealing the other mouth 10b, the relationship between the folding angle θ2 along the folding line 35 and the folding angle θ1 of the bag body 10 is the same as that shown in the drawing.

Next, as shown in FIG. 5, the square-shaped mouth sealing sheet 31 is placed so that the four corners of the mouth sealing sheet 31 and the four edges of the open surfaces 11a, 11a substantially coincide with each other. Place on. This is a straight line K connecting the fold line 35 of the mouth sealing sheet 31 and the mouth ends H, H of the bag body 10.
It is easily possible if they are aligned.

Next, as shown in FIG. 6, folding is performed around the base line K so as to close the open surface. Thereafter, the hot plate is pressed so that the entire periphery of the placed mouth sealing sheet 31 is heat-sealed (the hatched portion in FIG. 6). In this case, side heat sealing of the bag body is usually performed. Thereafter, the tabs 29, 29 protruding from both sides of the bag body are cut off along the longitudinal ends of the bag body, and the protruding portion 28 of the bag body is cut off along the line F in the lateral direction. Complete the bag for the box.

The bag-in-box bag thus formed is suitably used for forming a bag-in-box by covering a cardboard box with the bag-in-box. here,
To fill the bag with contents such as mineral water, for example, the contents may be filled from the injection spout 25 provided in the flat portion 11.

[0021]

According to the present invention, with the above-described configuration, it can be folded compactly, and can be efficiently transported and stored in an empty bag state, and can be efficiently disposed of. Since the box is square, there is no gap in the corner of the cardboard box when the cardboard box is exteriorized, and the strength and drop strength when stacking the bag-in-box are improved compared to the case of the cardboard box alone. In addition, there is no need to blow air before filling the content liquid, and a barrier layer is easily secured by laminating a barrier layer on each pair of flat and side portions and the material forming the mouth sealing sheet. Bag-in-box bag having advantages such as being able to perform the above-described process, and a manufacturing method capable of efficiently obtaining a bag-in-box bag having such advantages. It is subjected.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an example of a bag-in-box bag according to the present invention.

FIG. 2 is an explanatory view showing one step of the manufacturing process of the bag for a bag-in-box of the present invention.

FIG. 3 is an explanatory view showing one step of a manufacturing process of the bag-in-box bag of the present invention.

FIG. 4 is an explanatory view showing one step of the manufacturing process of the bag-in-box bag of the present invention.

FIG. 5 is an explanatory view showing one step of the manufacturing process of the bag-in-box bag of the present invention.

FIG. 6 is an explanatory view showing one step of the manufacturing process of the bag-in-box bag of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Bag main body 11 ... Flat part 21 ... Fold line 22 ... Side part 25 ... Injection spout 31 ... Mouth sealing sheet 35 ... Fold line

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B65D 30/16-30/20 B65D 77/06 B31B 1/00-1/98 B31B 29/00-41 / 74

Claims (3)

(57) [Claims] 1. A tubular bag main body comprising: a pair of opposed flat portions; and a pair of opposed side portions formed so as to have fold lines each of which is folded inward in a fold shape. A bag body for a bag-in-box comprising a pair of mouth sealing sheets respectively sealing mouths at both ends of the bag body, wherein the bag body is any one of the pair of flat portions. And the bag body
The part is located on the fold line to open the mouths at both ends once.
Are set as the base points, and from each of these base points,
Make the first fold line to the edge of the mouth reverse to the original fold direction
Fold out the side part to pull out the bag body part
The line connecting from the four corners of each to the base point is convex in the inward direction of the bag.
The open surface formed to be folded as a ridgeline
Formed at the mouths at both ends, the pair of flat portions and the pair of side portions are heat-sealed at the peripheral edges, and the pair of mouth sealing sheets are folded inward in a fold shape, respectively. A bag body for a bag-in-box, characterized in that these opening sealing sheets are formed so as to be heat-fusible and foldable at respective open surfaces and peripheral edges of the bag main body. . 2. A cylindrical bag main body comprising: a pair of opposed flat portions; and a pair of opposed side portions formed so as to have folding lines each of which is folded inward in a fold shape. A method for manufacturing a bag for a bag-in-box, comprising a pair of mouth sealing sheets each of which seals the mouths at both ends of the bag body and is folded inward in a folded manner. A bag body forming step of forming a cylindrical bag body by heat-sealing a pair of flat portions and the pair of side portions at peripheral edges, and each opening of the cylindrical bag body obtained in the bag body forming step. Forming a notch corner by cutting four corners of the portion, and using each arbitrary point in the folding line of each of the pair of side portions as a base point to open each mouth, from the base point to each mouth end Fold the first fold line out of the original fold direction and pull out A step of forming each open surface in which the inside of the bag is exposed by folding a line connecting from the cut corner of the bag body to the base point as a ridge line protruding inwardly of the bag, and Manufacturing a bag body for a bag-in-box, comprising a step of mounting a square-shaped mouth sealing sheet and a step of heat-fusing each peripheral edge of each of the mounted mouth sealing sheets. Method. (3) The open surface is shaped so that it is substantially coplanar.
The bag-in according to claim 1, wherein the bag-in is formed.
Box bag.