JPH06278771A - Composite container and manufacture thereof - Google Patents

Abstract

PURPOSE:To provide a composite container and manufacture thereof wherein the amount of plastic needed for manufacturing the container is reduced to remedy environmental problems, shock-absorbing characteristics of an inner container are enhanced, and the integration of the inner container and outer container is improved. CONSTITUTION:An outer container 4 of cylindrical paper having shape-keeping property is fitted into an engaging part 2 provided on the upper end of an inner container 1 of thin-wall plastic, whereby the outer container 4 is integrated with the inner container 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a container for storing and maintaining contents such as liquids and a method for manufacturing the container. More specifically, the present invention relates to a composite container in which an outer container made of paper for holding the shape and an inner container made of plastic for storing contents contained in the outer container are combined.

[0002]

2. Description of the Related Art Conventionally, a plastic container has been used as a container for storing contents such as foods, drinks, medicines, cosmetics and the like. If the container was made of plastic, the contents were used up, and when the container was no longer needed, it was discarded. However, it is more difficult to dispose of plastic containers than paper containers, and environmental pollution due to these plastic containers has become a problem in recent years.

On the other hand, an attempt was made to solve the above-mentioned problem by changing the container from a plastic container to a paper container. However, the paper container has a lower durability and impact resistance than the plastic container, and thus has a long life. Could not be used for a period.

Therefore, a composite container such as a bottle-in-box has been considered in which an inner container such as a bottle formed of thin plastic is inserted into an outer container made of paper or the like.

[0005]

In such a conventional composite container such as a bottle-in-box, the amount of plastic used can be reduced as compared with a container molded using only plastic. Further, by using paper as the outer container, it is possible to enhance the impact resistance and buckling strength of the inner container filled with the contents even if the side wall of the inner container is thin.

However, since the conventional inner container of a composite container such as a bottle-in-box has a bottle shape, the diameter is small and it is difficult to fill the inner container with contents such as liquid. Further, it may be necessary to form a hole in a portion in contact with the mouth portion in accordance with the diameter of the inner container of the outer container, which may take time and effort for molding.

Further, in the conventional composite container formed by winding the label-like outer container around the inner container, if the label-like material as the outer container is made thicker in order to increase impact resistance and buckling strength, Since the body of the container was thin, it was difficult to wind it, and the outer container could not be completely wrapped around the inner container.

Further, in the method of inserting the inner container into the outer container, it is necessary to apply an adhesive to the side surface of the inner container in order to integrate the inner container and the outer container. When inserting, the inner container and outer container need to be fitted to each other to some extent in order to weld them completely.Therefore, the adhesive may stick out from the adhesive surface of the inner container and outer container. There was a case where it could not be used as a container because it came into contact with the adjacent container and adhered thereto.

The present invention has been made in order to solve the above-mentioned problems, and reduces the amount of plastic used to solve environmental problems, enhances the impact resistance of the inner container, and makes the inner container and the outer container have a sense of unity. It is intended to provide a composite container having improved It also provides a particularly wide-mouthed composite container.

[0010]

According to the present invention, a cylindrical outer container made of paper having shape retention is fitted to a fitting portion provided at the upper end of an inner container made of thin plastic. A composite container in which the inner container and the outer container are integrated.

In this composite container, the inner container is blow-molded into a predetermined shape, and then the inner container is inserted into the cylindrical outer container to fit the outer container into the fitting portion of the inner container. A method of manufacturing a composite container, characterized in that an outer container and an inner container are integrated.

In this composite container, a cylindrical outer container is fitted into the fitting portion of the preform of the inner container formed by injection molding, and then the preform of the inner container is blow-molded. Is a method for manufacturing a composite container, characterized in that the outer container and the inner container are integrated.

[0013]

The composite container of the present invention comprises a cylindrical paper outer container having shape retention and an inner container having a fitting portion at the upper end, and the outer container is fitted into the fitting portion of the inner container. Molded by.

Further, a fitting portion is provided around the upper end formed by injection molding, a preform of the inner container having a wide mouth is formed, and then the preform of the inner container is blow-molded. A method for molding a composite container by molding the inner container and fitting the tubular outer container into the fitting portion of the inner container, or a tubular outer container in the form of the preform of the inner container. The composite container of the present invention is formed by a method of forming a composite container by fitting the inner container by blow molding and then by fitting the inner container by blow molding. The inner container is molded by biaxial stretch blow molding.

By fitting the cut-in fitting portion of the inner container and the locking fitting portion of the outer container, it is possible to give a feeling of unity between the inner container and the outer container. In addition, since the inner container is formed by thin-walled plastic, the amount of plastic used can be reduced and environmental problems can be improved. In addition, the impact resistance of the inner container can be enhanced by adjusting the thickness of the side wall of the inner container. Further, since the outer container covers the inner container without any gap, the impact resistance of the inner container can be enhanced.

Further, since the preform of the inner container before molding has a biaxially stretched portion, the impact resistance can be enhanced as compared with the direct molding portion.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the drawings. 1 is a cross-sectional view of the composite container after fitting according to the present invention, FIG. 2 is a perspective view of the composite container after fitting according to the present invention, and FIG. 3 is a preform of an inner container according to the present invention before being molded.

The plastic used in the inner container (1) can be blow molded by polyethylene terephthalate, polyethylene, polypropylene, polyacrylonitrile or the like. The plastic used in the inner container of this example is polyethylene terephthalate.

The thickness of the side wall of the inner container (1) varies depending on the size of the container, the type of contents, etc.
It is desirable that the distance is between 1.0 mm and 1.0 mm. In this example, the inner container (1) has a thickness of 0.2 mm.

The paper used for the outer container (4) is cardboard,
Examples include cardboard and plastic molded products. The paper used in this embodiment is cardboard. The shape of the outer container (4) is not limited to the tubular shape like a paper tube as shown in FIG. 1, but may be a paper box provided with a bottom plate or a cup shape. Further, when the inner container and the outer container are fitted by force fitting, it is not necessary to process the outer wall surface near the upper end of the outer container (4). However, as shown in FIG. 1, in order to more firmly fit the fitting portion (2) of the inner container, the notch fitting portion (5) or the like may be provided on the outer wall surface near the upper end. . The thickness of the outer container (4) depends on the rigidity of the paper used, the size of the inner container (1) protected by the outer container (4), the inner container (1) and the outer part against the external impact on the composite container. It can be changed according to the impact resistance of the container (4) and the like. The outer container (4) in this embodiment has a paper tube shape and a thickness of 1.0 mm.

As shown in FIG. 3, the preform of the inner container (1) is formed by injection molding. The preform has a shape in which the upper opening is substantially circular, the side surface is provided vertically downward at a constant length, and is closed at the center by a bottom portion (6) which is tapered inwardly, A fitting part (2) having a fitting part (3) at an interval approximately equal to the thickness of the outer container (4) is provided around the upper end of the inner wall of the inner container (1). Fitting part (3)
The inner container (1) is modified by changing the length of the fitting side surface (7) which is the outer side surface and the length of the upper surface (8).
The strength with which the outer container (4) is fitted can be changed. Further, by making the upper surface (8) facing the outer side of the upper part of the fitting portion (3) substantially parallel, for example, an inner lid is provided in the composite container, and the inner lid and the upper surface (8) are heat-bonded. The container can be sealed by. Further, by providing the screw part (9) on the upper outer wall surface of the fitting part (3), the container can be sealed by the screwed lid.

Example 1 In the method of manufacturing the composite container according to the first embodiment of the present invention, the preform molded by injection molding is blow-molded so that the wall surface of the composite container has a predetermined wall shape. Mold the inner container (1). Next, insert the outer container (4) made of paper and having the shape fitting property around the outer wall surface near the upper end and having the cut fitting part (5) into the fitting part (3) of the inner container (1). As a result, the outer container (4) and the inner container (1) are integrated by fitting the notch fitting part (5) of the outer container (4) with the fitting part (2) of the inner container (1). The composite container is molded.

<Embodiment 2> In the manufacturing method of the second embodiment of the composite container of the present invention, the above preform is molded by injection molding, and then the notch fitting portion (5) is formed on the outer wall surface near the upper end. By inserting the outer container (4), which is made of paper and has shape retention properties, into the fitting part (3) of the inner container (1), the cut fitting part (5) of the outer container (4) is inserted. ) Is fitted with the fitting portion (2) of the inner container (1). Then, the preform of the inner container is blow-molded, and the side surface of the inner container (1) and the side surface of the outer container (4) are brought into contact with each other, whereby the outer container (4) and the inner container (1) are integrated with each other. Is molded.

[0024]

As described above, in the composite container of the present invention, the outer container and the fitting portion provided on the inner container are fitted to each other, so that the outer container and the inner container are wide even if the inner container has a wide mouth. Can create a sense of unity.

The shape of the preform of the inner container is
Since the top surface is opened in a substantially circular shape and the bottom surface is closed, a composite container having a wide mouth can be easily molded.

Further, since the inner container is formed of thin plastic, the amount of plastic used can be reduced, and therefore environmental problems can be solved.

Since the inner container and the outer container are fitted together, the amount of adhesive used can be reduced, and the inner container and the outer container can be easily separated. Therefore, the disposal process can be facilitated.

Further, the impact resistance of the inner container can be enhanced by adjusting the thickness of the wall surface of the inner container. Since the outer container covers the inner container without any gap, the impact resistance and buckling strength of the inner container can be enhanced.

Further, since the preform before molding the inner container is formed by injection molding, the inner container can be multi-layered, that is, an inner container having properties such as gas barrier property and impact resistance can be easily obtained. Moreover, since the fitting portion can be easily molded, the working efficiency can be improved.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a combined container of the present invention after fitting.

FIG. 2 is a perspective view of the composite container after fitting according to the present invention.

FIG. 3 is a preform before molding of the inner container of the present invention.

[Explanation of symbols]

 1 ... Inner container 2 ... Fitting part 3 ... Fitting part 4 ... Outer container 5 ... Notch fitting part 6 ... Bottom part 7 ... Fitting side face 8 ... Top surface 9 ... Screw part

Claims (3)

[Claims] 1. A shape-retaining tubular outer container made of paper is fitted into a fitting portion provided at the upper end of an inner container made of thin plastic, whereby the inner container and the outer container are integrated. A composite container that is characterized by 2. An inner container is blow-molded into a predetermined shape, and then the inner container is inserted into a cylindrical outer container.
A method for manufacturing a composite container, characterized in that the outer container and the inner container are integrated by fitting the outer container into the fitting portion of the inner container. 3. A tubular outer container is fitted into a fitting portion of a preform of an inner container formed by injection molding, and then the preform of the inner container is blow-molded to form an inner container and an inner container. A method for manufacturing a composite container, characterized by integrating the containers.