JP2995190B1 - Manufacturing method of bag container - Google Patents

Abstract

An object of the present invention is to provide a manufacturing method for efficiently manufacturing a bag container having a spout capable of smoothly discharging contents. A sheet 1 in which a spout portion of a bag container is overlapped.
After interposing a mandrel 70 having an asymmetrical cross section between the first and second molds 7a and 1b, the first mold 7 is placed from the outside of both stacked sheets.
It is formed by pressing with the fifth die 73 and the second die 73.
In this case, the mandrel 70 is not heated, the first mold 75 is heated to a temperature equal to or higher than the melting point of the sealant layer of the sheet 1a, and the second mold 73 is heated to 9% of the melting point temperature of the sealant layer of the sheet 1b.
Keep the temperature below 0%.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a bag container for storing a liquid such as a liquid food or a seasoning, a liquid detergent or the like, and a granular material such as powdered soap (hereinafter referred to as a container). About.

[0002]

2. Description of the Related Art Conventionally, refillable and disposable types are widely used as bag containers for storing the above-mentioned contents. A bag container of this type is usually formed by stacking flexible sheets and heat-sealing the end regions thereof, and a spout for taking out the contents is provided in the upper region. ing. A score line is formed in the spout, and the spout is opened by tearing the score line by hand to take out the contents.

[0003] By the way, when the contents are poured out, it is preferable that the spout is always open during the pouring process. Otherwise, if the bag is not pressurized by pushing it by hand, the dispensing will not be performed smoothly.

[0004] In a bag container formed by stacking flexible sheets as described above, a score line is simply formed in the spout portion, and the score line is torn to open the spout, so that the spout is smoothly performed. Can not be done. This is because the opposing inner surfaces at the spout after tearing are
This is because they adhere due to a decrease in internal pressure that occurs with the outflow of the contents. Therefore, in order to prevent close contact of the spout, the spout is processed so that the cross-sectional shape of the spout after being cut along the score line is substantially circular or elliptical.

However, even if the cross-sectional shape of the spout is substantially circular or elliptical, the opposing inner surfaces of such a spout come into close contact in the process of taking out the contents. This is because the cross-sectional shapes of the spouts are symmetrical, and the lengths of the opposing surfaces are equal to each other, so that the two can easily adhere to each other. In addition, a bag container in which a pipe-shaped member is attached to the spout portion and the shape of the opening is maintained has been proposed, but the manufacturing process becomes complicated and the cost increases. I will.

It is also known that the bag container having the above-described spout is manufactured by air pressure molding or vacuum molding as disclosed in Japanese Patent Application Laid-Open No. 9-207950. The following problem arises with a simple manufacturing method.

[0007] Usually, a bag container used for the above-mentioned applications is constituted by a composite material comprising a polyolefin layer (sealant layer) such as polyethylene and polypropylene and a barrier layer such as aluminum, PET, nylon, and eval (EVOH). However, when pressure forming or vacuum forming is performed with such a commonly used composite material, cracks or cracks are formed due to the difference in the suitable temperature of the pressure forming or vacuum forming between the material of the sealant layer and the material of the barrier layer. Wrinkles are formed, making it difficult to form a uniform shaped shape, and the sheet thickness is locally reduced to a nonuniform thickness. In addition, a preheating time for molding the composite material, a time for holding the composite material by air pressure or a time for suctioning with a vacuum, and a cooling time for fixing the shape are required, which is a molding time. Becomes longer as a whole.

[0008] As described above, when pressure forming or vacuum forming is performed to manufacture a bag container using a composite material comprising a sealant layer and a barrier layer, it is difficult to mass produce high-quality bag containers at low cost. is there.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and is capable of efficiently producing a bag container having a spout capable of smoothly discharging contents without deteriorating the quality. The aim is to provide a method.

[0010]

In order to solve the above-mentioned problems, a method for manufacturing a bag container according to the present invention comprises stacking a sheet made of a composite material having a sealant layer and a barrier layer such that the sealant layers face each other. Thereafter, while forming a storage portion for storing the contents, in the manufacturing method of a bag container to be fused to form a spout for discharging the contents, the spout portion, between the stacked sheets After interposing a mandrel having an asymmetric cross-section so that the lengths of the opposing surfaces of the spouts are different, the first from the outside of both stacked sheets
The mandrel is shaped by pressing with a mold and a second mold, the mandrel is not heated, the first mold is heated to a temperature equal to or higher than the melting point of the sealant layer of the composite material, and the second mold is The temperature is set to 90% or less of the melting point temperature of the sealant layer.

As described above, in a bag container formed by stacking sheet materials, the cross section of the spout is formed so that the distance between the inner surfaces facing each other is different, so that the internal pressure of the storage portion of the bag container is increased. Even if the height is lowered, the close contact between the opposing surfaces is suppressed, and the contents can be smoothly discharged at the time of pouring.

[0012] In addition, the spout of the bag container as described above presses the first mold and the second mold from outside of both sheets after interposing a mandrel having an asymmetric cross section between the stacked sheets. Created by: At this time, the mandrel is not heated and one of the molds (first mold) is heated to a temperature equal to or higher than the melting point of the sealant layer, so that the overlapped sheet is shaped as a spout according to the cross-sectional shape of the mandrel. And there is no cooling process to fix the shape,
This is almost the same as the normal heat seal bag making process, and the processing time is shortened. Further, the influence of the difference in the melting point (appropriate processing temperature) of each composite material constituting the sheet is reduced, the generation of cracks and wrinkles in the spout portion is suppressed, and the shaping and forming can be performed in a short time. . By making the other mold (second mold) 90% or less of the melting point temperature of the sealant layer of the sheet, the time required for the fusion processing of the spout can be reduced by that much, and the production efficiency can be reduced. Improvement can be achieved. In this case, if the heating temperature of the other mold (the second mold) is too high, thermal deformation of the sealant layer becomes large, and cracks and wrinkles are likely to be generated in the spout portion. It is kept below 90% of the melting point temperature of the layer.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First, an example of the configuration of a bag container obtained by the method for producing a bag container of the present invention will be described.
In this case, the spout in each configuration example is created by interposing a mandrel having an asymmetrical cross section and pressing the mandrel with a mold.

FIGS. 1A and 1B are diagrams showing a first configuration example of a bag container, wherein FIG. 1A is a diagram showing an overall shape, and FIG.
FIG. 3 is a cross-sectional view taken along line AA of FIG.

The bag container 1 includes a polyolefin layer of polyethylene, polypropylene or the like (a layer to be heat-sealed and defined as a “sealant layer”), aluminum, PET,
Composite materials 1a and 1b composed of barrier layers such as nylon and EVAL (materials used differ depending on the application) are overlapped so that the sealant layers are opposed to each other, and the parts indicated by oblique lines are heat-sealed. Is done. In this case, the bag-making method may be performed by a leaf-by-leaf process, or may be performed by drawing out a composite material that has been rolled in advance and continuously processing the composite material.

In the actual bag-making process, the storage portion for storing the contents is formed in a state where a part (in the example shown in the figure, an upper area denoted by reference numeral 1c) is opened, and the storage part is formed from this part. Is accommodated in the internal space 2 and then the opening 1c is heat-sealed to complete the bag container accommodating the contents. Further, the bag container to be manufactured may have a shape in which two sheets are simply stacked, or as shown in FIG.
A self-dimensional shape may be formed by interposing the character-shaped sheet 1d, and the overall shape is not limited.

When a bag container is manufactured, a spout 10 is formed at an upper portion thereof by a method described later. There may be a score line 11 in the spout portion, and the spout 10 is opened by tearing this portion.

The spout 10 is formed such that when it is cut along the score line 11, the cross-sectional shape is asymmetrical so that the length of each of the opposing surfaces is different on the front and back of the bag (in this case, the spout 10). A symmetrical shape means a circular cross section or an elliptical cross section in which the lengths of the opposing surfaces are equal. In this embodiment, the bag is formed linearly on the front side 1a and is formed in an arc shape of 180 ° on the back side 1b, and has a semicircular shape as a whole. For this reason, the opposing inner surfaces have different lengths, and when the contents are actually poured, even if the internal pressure is reduced, they are prevented from being in close contact with each other, and a smooth pouring operation can be performed. In addition, other than such a semicircular shape, for example, a semielliptical shape may be used.

FIG. 2 is a view showing a second configuration example of the bag container. The spout 20 in this configuration example is the front side 1 of the bag.
a, an arc-shaped portion of 180 ° is formed on each of the back side 1b, and these are shifted from each other to form the opening 20.
a and 20b are formed. Also in this configuration example, since each opening has a different length of the facing inner surface,
When the contents are actually dispensed, even if the internal pressure is reduced, the contents are prevented from adhering to each other, and a smooth dispensing operation can be performed. In this way, the spouts with different lengths of facing surfaces are
A plurality may be formed.

FIG. 3 is a view showing a third configuration example of the bag container. In the spout 30 of this configuration example, two small-diameter 180 ° arc-shaped portions are formed on the front side 1a of the bag, and one large-diameter 180 ° arc-shaped portion is formed on the back side 1b. Are shifted from each other so that the openings 30a, 30b and 3
0c is formed. Also in this configuration example, as in the above, when the contents are poured out, even if the internal pressure is reduced, they are prevented from coming into close contact with each other, and a smooth pouring operation can be performed.

FIG. 4 is a view showing a fourth configuration example of the bag container. In the spout 40 of this configuration example, a rectangular opening 40a extending to the axially intermediate region of the spout 40 is formed on the front side 1a of the bag, and the axial tip of the axial spout 40 is formed on the back side 1b. A semicircular opening 40b extending to the region is formed. As described above, the spouts having different lengths of the opposing surfaces may be formed so as to be shifted from each other in the axial direction. Also in this configuration example, as in the above, when the contents are poured out, even if the internal pressure is reduced, they are prevented from coming into close contact with each other, and a smooth pouring operation can be performed.

FIG. 5 is a view showing a fifth configuration example of the bag container. In the spout 50 of this configuration example, a semicircular opening 50a extending from the axial base end of the spout 50 to the intermediate region is formed on the front side 1a of the bag, and the axial base 50b is formed on the back side 1b. A semicircular opening 50b extending from the end to the tip region is formed. For this reason, the base region of the spout 50 has a circular cross section by the opening 50a on the front side 1a and the opening 50b on the back side as shown in FIG. As shown in (c) and (d), only the opening 50b has a semicircular shape. As described above, the spout may have a configuration in which a portion having an asymmetric shape is formed in a part in the axial direction. Also in this configuration, as in the above, when the contents are poured out, even if the internal pressure is reduced, the contents are prevented from being in close contact with each other, and a smooth pouring operation can be performed.

Next, with reference to FIG. 6, a method of manufacturing a bag container for forming the above-described spout portion in an actual bag making process will be described. The manufacturing method shown in the drawing shows a method of forming a spout having a semicircular cross section as shown in FIG.

As shown in FIG. 6A, sheets 1a and 1b made of a composite material having a sealant layer and a barrier layer
Are arranged such that the respective sealant layer sides face each other. At the time of this arrangement, the accommodation portion accommodating the contents is subjected to fusion processing with a part thereof being opened. A mandrel 70 having a semicircular cross section is interposed between the two sheets arranged so as to form the spout shown in FIG.
Then, in such an arrangement state, the concave sheet 73 having the arc-shaped concave section 73a formed thereon and the flat sheet 75 are pressure-bonded to each other, and the two sheets are thermally fused. In this case, the mandrel 70
Is maintained at room temperature, ie, not heated by special means.

The flat mold 75 of both the molds 73 and 75 is used.
Side is heated at a temperature higher than the melting point temperature of the sealant layer of the sheet 1a (high heating side), and the concave mold 73 is attached to the sheet 1b.
(Low-heating side). As described above, the flat mold 75 is heated at a high temperature and the concave mold 7 is heated.
In order to form a swelling asymmetric shape, if the swelling side (the longer facing surface) is set to high heating, it is easy to thermally deform and maintain a uniform shape and uniform thickness. Is difficult. The reason why the temperature of the concave shape on the low heating side is set to 90% or less of the melting point temperature of the sealant layer of the sheet 1b is that when the temperature is higher than this, the processing time is short, but the sealant layer tends to be thermally deformed. This is because wrinkles or cracks occur in the spout.

If the temperature of the concave mold 73 is too low (as in the case of the mandrel, if it is not heated), the time required for fusing becomes longer, and the production efficiency deteriorates. For this reason, the temperature of the concave mold 73 is preferably set to 90% or less of the melting point temperature of the sealant layer of the sheet 1b. Specifically, when a linear low-density polyethylene is used as the sealant, its melting point temperature is about 120 to 135 ° C., so the heating temperature of the concave mold 73 is in the range of 120 to 60 ° C., preferably, 120 ~
It is good to keep it at 80 ° C.

Then, as shown in FIG. 1B, both sheets 73 and 75 are separated from each other and the mandrel 70 is detached after the two sheets are heat-sealed by pressure bonding as shown in FIG.
As shown in (1), an asymmetric spout is formed in which one side bulges. Of course, it is possible to form a spout as illustrated in FIGS. 2 to 5 by changing the cross-sectional shape, the axial shape, and the like of the mandrel 70 described above.

According to the manufacturing method as described above, the spout is formed only by pressing the heated flat mold 75 against the concave mold 73 (compared to pressure forming or vacuum forming).
The heating time for forming the spout is extremely short, so that the influence of the heat shrinkage of each material in the composite material can be minimized, and the occurrence of cracks and wrinkles in the spout can be suppressed. In this configuration, since the concave mold 73 is also in a somewhat heated state, the time required for heat fusion of the two sheets can be shortened, and the manufacturing process is easy as described above. A good bag container can be manufactured.

In the case where the spout is formed by the above-described steps, the spout is likely to cause heat shrinkage because the spout is asymmetric. For this reason, in the actual heating step, it is desirable to temporarily fix the stacked sheets or to adjust the size of the sheet shape in consideration of the heat shrinkage portion.

The bag container body finally formed by the above-described manufacturing method is subjected to printing according to the intended use. In this case, it is desirable that the spout portion shaped as described above is made transparent without any particular printing. In this way, by making the spout portion transparent, it is easy to distinguish it from other products when it is actually displayed.

[0031]

As described above, according to the bag container manufacturing method of the present invention, since the lengths of the facing inner surfaces of the spouts of the bag container are different, when the contents are poured out, It becomes difficult for the outlet portion to adhere, and the contents can be smoothly taken out. And, since the bag container having such a configuration is manufactured with a mold having one high temperature and a mold having the other low temperature with an unheated mandrel interposed therebetween, in a short time and at low cost,
Moreover, mass production becomes easy without lowering the quality.

[Brief description of the drawings]

FIG. 1 is a view showing a first configuration example of a bag container manufactured according to the present invention, wherein FIG.
FIG. 2B is a sectional view taken along the line AA in FIG.

FIG. 2 is a diagram showing a second configuration example of a bag container manufactured by the present invention, wherein (a) is a diagram showing a spout portion;
FIG. 2B is a cross-sectional view taken along line BB in FIG.

FIG. 3 is a view showing a third configuration example of a bag container manufactured by the present invention, wherein (a) is a view showing a spout portion;
(B) is sectional drawing along CC line | wire of FIG. (A).

FIG. 4 is a diagram showing a fourth configuration example of the bag container manufactured by the present invention, wherein (a) is a diagram showing a spout portion;
(B) is a cross-sectional view along the line DD in FIG. (A), (c)
FIG. 4 is a cross-sectional view taken along line EE in FIG.

FIG. 5 is a view showing a fifth configuration example of the bag container manufactured by the present invention, and (a) is a view showing a spout portion;
(B) is a cross-sectional view along the line FF in (a) of FIG.
FIG. 4A is a cross-sectional view along the line GG in FIG. 4A, and FIG. 4D is a cross-sectional view along the line HH in FIG.

6A and 6B are views for explaining the method for manufacturing a bag container according to the present invention, in which FIG. 6A shows a state in which a sheet, a mold and a mandrel are set, and FIG. 6B shows a crimped state. .

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Bag container, 1a, 1b ... Sheet (composite material), 2 ... Internal space, 10, 20, 30, 40, 50 ... Spout, 70 ...
Mandrel.

Claims (3)

(57) [Claims] 1. After laminating a sheet made of a composite material having a sealant layer and a barrier layer such that the sealant layer is opposed to the sheet, a storage portion for storing contents is formed,
In the method for manufacturing a bag container that is fused so as to form a spout for discharging the contents, the spout portion is formed between the stacked sheets such that lengths of opposing surfaces of the spouts are different. After interposing a mandrel having an asymmetrical cross section, the first and second molds press the outer and outer sides of both stacked sheets to shape the mandrel. A method for manufacturing a bag container, comprising heating the composite mold to a temperature equal to or higher than the melting point of the sealant layer of the composite material and setting the second mold to a temperature equal to or lower than 90% of the melting point temperature of the sealant layer of the composite material. 2. The method according to claim 1, wherein the mandrel has a semicircular or semielliptical cross section. 3. The method for manufacturing a bag container according to claim 1, wherein the first mold has a shorter length of a surface facing the spout to be shaped.