JPH08244746A - Container formed by biaxially stretched blow molding - Google Patents

Abstract

PURPOSE: To propose a container formed by biaxially stretched blowing molding which when empty or not containing liquid can be folded into a flat or small object. CONSTITUTION: A PET bottle 1 has a tubular drum part 2 which is rectangular in cross section, a neck part 3 which is a tapering continuation of the drum part 2 extending from its upper end 21, a mouth 4 formed at the upper end of the neck part 3, and a bottom 5 which is rectangular and formed at the lower end of the tubular drum part 2. Each of the four side walls 22, 23, 24, 25 of the tubular drum part 2 is a curved wall with the middle part with respect to both the width and height (axial direction) curved inward. With a thickness in the range from about 0.03mm to about 0.07mm, any of these side walls can be folded inward in two at the middle in a simple manner and by folding over each of a pair of opposed side walls the bottle can be made flat as a whole. By folding it over lengthways further the bottle can be made much less bulky than before.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a biaxially stretch blow molded container for containing a liquid such as liquor or soy sauce. More specifically, the present invention relates to a biaxially stretch blow-molded container that can be flattened or folded in an empty state not filled with liquid.

[0002]

Liquids such as alcoholic beverages, soy sauces, and milk are generally filled in PET bottles or paper packs and are on the market. Other forms of liquid containers include flexible bags formed by adhering polypropylene sheets to a box made of corrugated cardboard, as seen in commercial vinegar and soy sauce containers. A double structure with a built-in is known.

[0003]

It is conceivable that alcohol and milk sold in PET bottles, paper packs, etc., will also have the double structure as described above. However, if a bag is formed by fusion-bonding a plurality of polypropylene sheets as in the conventional case, the number of manufacturing steps is large, and the manufacturing cost is low and the manufacturing cannot be performed efficiently.

In view of the above points, an object of the present invention is to propose a biaxially stretch blow-molded container having new features suitable for use in a double-structured liquid container. It is in.

[0005]

In order to solve the above-mentioned problems, the present invention relates to a plastic container which is biaxially stretch-blow-molded, and has a cylindrical body having a polygonal cross section and an upper end of the body. Has a tapered neck portion, an opening formed at the upper end of the neck portion, and a bottom portion formed at the lower end of the tubular body portion, at least each side wall of the tubular body portion,
When cut in a direction orthogonal to the axial direction of the tubular body, the central portion is formed to have a curved side wall that is curved inward as compared with the both side portions, and the out-of-plane rigidity of each side wall is , These are set to a low value such that they can be folded inward with the center part as the center, and by folding the side walls in two, the tubular body is made flat. It has a structure that allows it to be folded.

Here, the side walls of the tubular body can be made foldable by setting the thickness to about 0.1 mm or less. Desirably, the thickness is in the range of about 0.03 mm to about 0.07 mm.

Next, according to the present invention, in a biaxially stretch blow molded plastic container, a tubular body having a rectangular cross section, and a tapered neck portion continuous to the upper end of the body,
There is an opening formed at the upper end of the neck portion, and a rectangular bottom portion formed at the lower end of the tubular body portion, and among the four side walls of the tubular body portion, at least a pair of opposing side walls are When cutting in the direction orthogonal to the axial direction of the tubular body,
It is formed so that the center part becomes a curved side wall that is curved inward as compared to the both side parts, and the out-of-plane rigidity of these pair of side walls is folded inward with the center part as the center. It is set to a value as low as possible, and by adopting a configuration in which the pair of side walls is folded in two, the tubular body portion having a rectangular cross section can be folded into a flat state.

In this case, when all of the four side walls of the tubular body are cut in a direction orthogonal to the axial direction of the tubular body, the central portion is curved inwardly as compared with the both side portions. The sidewalls can be formed so as to have curved sidewalls, and the out-of-plane rigidity of each sidewall can be set to a low value such that the sidewalls can be folded inward about the central portion.

Further, each side wall of the tubular body can be made foldable by setting the thickness to about 0.1 mm or less. This thickness is preferably in the range of about 0.03 mm to about 0.07 mm.

On the other hand, according to the present invention, in a biaxially stretch blow-molded plastic container, a tubular body having a rectangular cross section, and a tapered neck portion continuous with the upper end of the body,
There is an opening formed at the upper end of the neck portion, and a rectangular bottom portion formed at the lower end of the tubular body portion, and among the four side walls of the tubular body portion, at least a pair of opposing side walls are When cutting in the direction orthogonal to the axial direction of the tubular body,
It is formed so that the center part becomes a curved side wall that is curved inward as compared to the both side parts, and the out-of-plane rigidity of these pair of side walls is folded inward with the center part as the center. It is set to a value as low as possible, and by folding the pair of side walls in two, it is possible to fold the tubular body having a rectangular cross section into a flat state. Is set to a dimension that is approximately an integral multiple of the length of one side of the bottom portion where the folded side walls are connected, and the out-of-plane rigidity of the cylindrical body portion in a flat state is Of the bottom portion is set to a low value such that it can be folded into a plurality of pieces in the axial direction.

In this case as well, it is possible to make it foldable by setting the thickness of each side wall of the tubular body to about 0.1 mm or less. This thickness is about 0.03 mm to about 0.03 mm. It is desirable to set it within the range of 0.07 mm.

[0012]

The container of the present invention can be flattened by folding the side wall of the cylindrical body part inward and folding it in two. Further, the flattened body portion can be folded into a plurality in the height direction. Folding in this way is convenient for transportation and the like. Further, even when it is disposed of after use, it does not become bulky by folding.

[0013]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an example of the biaxially stretch blow molded container of the present invention. The container 1 of this example is made of PET, and has a cylindrical body 2 having a rectangular cross section, a tapered neck 3 continuous with an upper end 21 of the body 2, and an upper end 31 of the neck 3. It has an opening 4 formed therein and a rectangular bottom portion 5 formed at the lower end of the tubular body portion 2. A male screw portion 41 for mounting a cap (not shown) is formed on the outer periphery of the opening 4. The container 1 of this example has widths W1 and W2 and a body portion height H. Height H is
It is an integral multiple of the width W2.

The four side walls 22, 23, 2 of the cylindrical body 2
As shown in FIG. 1 (c), reference numerals 4 and 25 are such that the cross-sectional shape orthogonal to the axial direction of the tubular body is a curved side wall in which the central portion is curved inward as compared to the both side portions. Has been formed. That is, the central portions 22a, 23a, 24a, 25a of the respective side walls are curved inward with respect to the corners 26, 27, 28, 29. Similarly, as shown in FIG. 1 (b), the vertical cross-sectional shape cut along the axial direction of the body has a vertical center with respect to the upper end 31 on the neck 3 side and the end on the bottom 5 side. The part of is curved inward. Thus, each side wall 22, 23, 24, 25
Has a curved wall in which central portions in the width direction and the height direction (axial direction) are curved inward.

In order to blow-mold each side wall so as to form such a curved wall, the thickness of each side wall may be reduced and the reinforcing portion such as a lateral rib may not be formed. In this example, the thickness of each side wall is set to 0.1 mm or less. The thickness of these side walls is about 0.0
Values in the range of 3 mm to about 0.07 mm are preferred. If the side wall is blow-molded to have such a thickness and the reinforcing parts such as lateral ribs are not attached,
After the demolding, the side wall portion contracts to obtain a shape in which the central portion is curved inward as shown in FIG.

PE biaxially stretch blow molded in this way
As shown in FIG. 2A, if the T container 1 is crushed from the pair of side walls 22 and 24, the side walls 23 and 25 in the orthogonal direction are inwardly centered on the central portion thereof. It is folded in half.

As a result, as shown in FIG. 2B, the body can be flattened until the side walls 22 and 24 are superposed on each other, and as shown in FIG. The tubular body portion 2 can be crushed into a flat shape having a width W1 and a height H as a whole. Since the neck 3 and the bottom 5 of the container have high rigidity, they retain their original shapes.

Further, in the PET container 1 of this example,
The thickness of the side wall is 0.03 mm to 0.07 mm. Since the PET bottle that is generally used has a thickness of about 0.3 mm, it is extremely thin. Further, as described above, no lateral ribs or the like for holding the molded shape are attached to each side wall. Therefore, as described above, each side wall can be folded in two to flatten the tubular body portion 2, and further, the flattened tubular body portion 2 can be folded in its height direction (axial direction). You can

FIG. 3 (a) shows this folded state, and FIG. 3 (b) shows the overall shape of the container after folding. As shown in this figure, the height h of the container after folding is a fraction of the initial height H of the container (see FIG. 1A). Also, since the height is an integral multiple of the width of the bottom, it can be folded to the size of the bottom of the container. Therefore, in such a state of being folded vertically and horizontally, a large number of containers 1
It can be stored and transported, and when used, it can be unfolded and filled with liquid.

The PET container 1 thus formed can be used, for example, as a double-structured container in a cardboard box having a similar shape and a size larger than the PET container 1. As the filling material, various things such as alcoholic beverages, soy sauce, and beverages can be considered.

In the above example, the container is made of PET.
Although it is manufactured, it goes without saying that other materials may be used. Further, the shape of the container is not limited to the rectangular shape. For example, it may be a cylindrical body having a triangular prism shape, or may be a cylindrical body having a polygonal prism shape with five or more pentagonal prisms. Furthermore, as can be seen from the above description, the container can be flattened if the pair of opposing side walls can be folded in two, so that the other side walls can be provided with rigidity that is difficult to fold. It may be formed as a thickness or as a ribbed sidewall.

[0023]

As described above, in the biaxially stretch blow-molded container of the present invention, the side wall of the container can be folded inward so that the container body can be flattened. Further, in the present invention, by folding the flattened container body also in its height direction (axial direction), its bulk can be made extremely small. Therefore, it is possible to realize a new container that does not take up much space for transportation and storage and can be returned to the original state and used at the time of use.

[Brief description of drawings]

1A and 1B are views showing a PET container of the present invention, in which FIG. 1A is a perspective view thereof, FIG. 1B is a longitudinal sectional view thereof, and FIG. 1C is a transverse sectional view of a central portion in the height direction thereof.

2A and 2B are views for explaining the folding operation of the container of FIG. 1, in which FIG. 2A is a cross-sectional view of the container before folding, and FIG.
[Fig. 3] is a cross-sectional view of the container after folding, and (c) is a vertical cross-sectional view of the container after folding.

3A and 3B are diagrams showing an operation of further folding the container after folding shown in FIG. 2 in a height direction, FIG. 3A is a side view showing a state in the middle of folding, and FIG. 3B is a state after folding. It is a side view.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 PET container 2 Cylindrical body part 22, 23, 24, 25 Side wall 26, 27, 28, 29 Side wall corner part 3 Neck part 4 Opening 5 Bottom part

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[Procedure amendment]

[Submission date] April 10, 1995

[Procedure Amendment 1]

[Document name to be corrected] Drawing

[Correction target item name] All drawings

[Correction method] Change

[Correction content]

FIG.

[Fig. 2]

[Figure 3]

Claims (10)

[Claims] 1. A biaxially stretch-blow-molded plastic container, wherein a cylindrical body having a polygonal cross section, a tapered neck continuous with an upper end of the body, and an upper end of the neck are formed. Has an opening and a bottom formed at the lower end of the tubular body, and at least each side wall of the tubular body has both sides when cut in a direction orthogonal to the axial direction of the tubular body. It is formed so that the central portion becomes a curved side wall that is curved inward as compared with the portion, and the out-of-plane rigidity of each side wall can be folded inward about the central portion. It is set to a low value, and by bi-folding each side wall, it is possible to fold the tubular body in a flat state. Container. 2. The method according to claim 1, wherein each side wall of the tubular body portion has a thickness of about 0.1 mm or less,
A biaxially stretch blow-molded container characterized by being foldable. 3. The biaxially stretch blow molded container according to claim 2, wherein the thickness of each side wall of the tubular body is in the range of about 0.03 mm to about 0.07 mm. 4. A biaxially stretch blow-molded plastic container, wherein a tubular body having a rectangular cross section, a tapered neck continuous with an upper end of the body, and an upper end of the neck are formed. An opening and a rectangular bottom portion formed at the lower end of the tubular body portion, of the four side walls of the tubular body portion,
At least the pair of side walls facing each other are formed such that, when cut in a direction orthogonal to the axial direction of the tubular body, the central side portion is a curved side wall that is curved inward as compared with both side portions. , The out-of-plane rigidity of the pair of side walls is set to a low value such that the pair of side walls can be folded inward about the center portion thereof. A biaxially stretch blow-molded container, characterized in that the tubular body of the cross section can be folded into a flat state. 5. The central portion of claim 4, when all of the four side walls of the tubular body portion are cut in a direction orthogonal to the axial direction of the tubular body portion, the central portion is inside as compared with the both side portions. It is formed so as to form a curved side wall that is curved inward, and the out-of-plane rigidity of each side wall is set to a low value that allows the side walls to be folded inward with the central portion as the center. A characteristic biaxially stretch blow molded container. 6. The biaxial stretching according to claim 4, wherein each side wall of the tubular body is foldable by setting the thickness to about 0.1 mm or less. Blow molded container. 7. The biaxially stretch blow molded container according to claim 6, wherein the thickness of each side wall of the tubular body is in the range of about 0.03 mm to about 0.07 mm. 8. A biaxially stretch-blow-molded plastic container, wherein a tubular body having a rectangular cross section, a tapered neck continuous with the upper end of the barrel, and an upper end of the neck are formed. An opening and a rectangular bottom portion formed at the lower end of the tubular body portion, of the four side walls of the tubular body portion,
At least the pair of side walls facing each other are formed such that, when cut in a direction orthogonal to the axial direction of the tubular body, the central side portion is a curved side wall that is curved inward as compared with both side portions. , The out-of-plane rigidity of the pair of side walls is set to a low value such that the pair of side walls can be folded inward about the center portion thereof. It is possible to fold the tubular body of the cross section into a flat state, and the height of the tubular body is approximately the length of one side of the bottom portion where the folded side walls are connected. The out-of-plane rigidity of the cylindrical body, which is set to an integral multiple and is in a flat state, is set to a low value such that it can be folded into a plurality of pieces in the axial direction at the size of the bottom portion. Biaxial stretch blow molding characterized by being Containers. 9. The sidewall of the tubular body according to claim 8, wherein the thickness is set to about 0.1 mm or less,
A biaxially stretch blow-molded container characterized by being foldable. 10. The biaxially stretch blow molded container according to claim 9, wherein the thickness of each side wall of the tubular body is in the range of about 0.03 mm to about 0.07 mm.