COMPOSITE CONTAINER, PACKAGE BODY, AND METHOD FOR MANUFACTURING COMPOSITE CONTAINER

Info

Publication number: 20150041527
Type: Application
Filed: Mar 22, 2013
Publication Date: Feb 12, 2015
Applicant: CHOKOKU PLAST CORPORATION (Osaka-shi, Osaka)
Inventor: Kenichi Asai (Neyagawa-shi)
Application Number: 14/387,110

Abstract

The objective of the present invention is to provide a composite container, as represented by a composite container which has a gas barrier property, an anti-moisture property, a shape retaining property, an anti-shock property, an easy-to-open property, and a resealing function, can be easily opened, and facilitates the extraction of the contents. A composite container having a gable top shape in which a paper board is attached to an outer peripheral surface of a pillow type bag constituted by a resin film and having an end seal section and a center seal section, wherein the paper board is attached to the resin film in at least a body portion of the composite container; in an upper part of the composite container, the resin film and the paper board are gazette-like folded while being attached to each other in such a manner that an end portion of the resin film protrudes from an end portion of the paper board, and the end portion of the resin film forms the end seal section; and an inner peripheral surface of the paper board of the composite container is attached at an entire surface or part thereof to the resin film below the end seal section protruding from the end portion of the paper board.

Description

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a composite container constituted by a resin film and a paper board and to a manufacturing method thereof.

2. Description of the Related Art

A method that has been conventionally widely used for providing food and confectionary involves accommodating the contents in a flexible packaging material such as a plastic film, and then further accommodating the package body in a rigid outer packaging material (outer box) made of paper, or the like, for distribution. In such composite containers, the contents can be protected from damage, or the like, by the outer packaging material while, for example, gas and moisture barrier properties are ensured by the flexible packaging material. Further, since the outer packaging material has a shape retaining property, the composite containers can be arranged neatly in the stores.

With the above-described composite container, first, the outer packaging material is opened, the package body contained therein is taken out, and then the flexible packaging material is opened, to extract the contents such as food and confectionary. In this case, where the entire contents are not consumed at once and the rest thereof is to be stored, the mouth of the flexible packaging material is sealed by some means, and the flexible packaging material is again accommodated in the outer packaging material. However, since the flexible packaging material has no shape retaining property, the shape and volume thereof change significantly with respect to those of the original package body, and the flexible packaging material cannot be smoothly accommodated in the outer packaging material, or in some cases the outer packaging material is deformed and the flexible packaging material cannot be accommodated successfully. For this reason, once the conventional composite container has been opened, it is thereafter used while the appearance of the outer packaging material is hardly attractive, or only the outer packaging material is discarded.

In a well-known type of a composite container constituted by a flexible packaging material and an outer packaging material, the outer peripheral surface of the flexible packaging material is attached to the inner peripheral surface of the outer packaging material (for example, Patent Documents 1 and 2). In order to facilitate the opening of such composite containers, the outer packaging material and the inner packaging material are devised to enable the integral opening thereof.

However, a method that is mainly used when the composite container described in Patent Document 1 is opened and the contents are extracted therefrom involves grabbing the contents by a hand or tilting the container to allow the contents to fall down. Therefore, the flowable contents such as liquids or granules cannot be accommodated in such container. Another problem is that when the contents are extracted, the hand is soiled, and when the contents is allowed to fall down, the extraction amount of the contents is difficult to be controlled.

Further, in the composite container described in Patent Document 2, the paper board and the laminated film are torn integrally along an opening line in a body portion, and the opened composite container is split in two. The resultant problem is that the container has no resealing function, and where the contents are not consumed at once, the remaining contents should be accommodated in another container.

Patent Document 1: Japanese Patent Application Publication No. 2000-211637

Patent Document 2: Japanese Patent Application Publication No. 2000-229662

SUMMARY OF THE INVENTION Problems to be Solved by the Invention

With the foregoing in view, it is an objective of the present invention to provide a composite container, as represented by a composite container which has a gas barrier property, an anti-moisture property, a shape retaining property, an anti-shock property, an easy-to-open property, and a resealing function, can be easily opened, and facilitates the extraction of the contents.

Means for Solving the Problems

The inventors have conducted a comprehensive research to attain the abovementioned objective. The results obtained have demonstrated the effectiveness of a gable top-shaped composite container obtained by bonding together a resin film and a paper board, and this finding led to the creation of the present invention. Thus, the present invention has the following features.

(1) A composite container having a gable top shape in which a paper board is attached to an outer peripheral surface of a pillow type bag constituted by a resin film and having an end seal section and a center seal section, wherein

the paper board is attached to the resin film in at least a body portion of the composite container;

in an upper part of the composite container, the resin film and the paper board are gazette-like folded while being attached to each other in such a manner that an end portion of the resin film protrudes from an end portion of the paper board, and the end portion of the resin film forms the end seal section; and

an inner peripheral surface of the paper board of the composite container is attached at an entire surface or part thereof to the resin film below the end seal section protruding from the end portion of the paper board.

(2) The composite container according to (1) above, wherein a spout for extracting container contents can be formed by cutting off at least one of left and right end portions of the end seal section and drawing out a portion that has been gazette-like folded.

(3) The composite container according to (1) or (2) above, wherein

at least an inner surface of the resin film of the end seal section is sealed by an easy-to-open resin layer or an easy-to-open resin film, and

a spout for extracting the contents can be formed by peeling off a portion sealed by the easy-to-open resin layer or the easy-to-open resin film of the end seal section of a gazette portion, and drawing out a portion that has been gazette-like folded.

(4) The composite container according to any of (1) to (3) above, wherein after the composite container has been opened, a portion forming the spout can be gazette-like folded again.

(5) The composite container according to any of (1) to (4) above, wherein a body portion cross section of the composite container has a quadrangular shape.

(6) The composite container according to any of (1) to (5) above, wherein

in a bottom portion of the composite container, the paper board is not attached to the outer peripheral surface including the end seal section of the pillow type bag.

(7) The composite container according to any of (1) to (6) above, wherein

a fold line for gazette-like folding is provided in the paper board.

(8) The composite container according to any of (1) to (7) above, wherein

a fold line for forming an outer shape of the main body of the composite container is provided in the paper board.

(9) The composite container according to any of clauses (1) to (8) above, wherein

the end portion of the paper board abuts against a base of the center seal section, and the center seal section is exposed on the outer peripheral surface of the paper board from between the end portion of the paper board and the other end portion of the paper board.

(10) The composite container according to any of (1) to (9) above, wherein one end portion of the paper board abuts against a base of the center seal section, the center seal section overlaps the outer peripheral surface of this end portion, and the other end portion of the paper board covers the center seal section.

(11) The composite container according to any of (1) to (10) above, wherein a notch or a cut with a width equal to or greater than the center seal width is provided in the paper board at the bottom of the composite container.

(12) The composite container according to any of (1) to (11) above, wherein a non-attached portion is present between the paper board and the resin film in a portion constituting the body portion of the composite container.

(13) The composite container according to any of (1) to (12) above, wherein the end seal section of the resin film at the upper part of the composite container has a vertical notch and a transverse notch and only part of the end seal section can be opened.

(14) The composite container according to any of (1) to (13) above, wherein the paper board and the resin film of the composite container are attached such that the paper board and the resin film can be easily peeled off and separated.

(15) The composite container according to any of (1) to (14) above, which is manufactured by

using a vertical Form-Fill-Seal machine in which the resin film is unwound from a film roll, and shaped into a tube in the vertical direction, and center-sealed, and then upper and lower ends of each pitch are sealed and cut to manufacture a pillow bag,

overlapping and at least partially bonding, for each pitch, a sheet-shaped paper board to an outer peripheral surface of the tubular resin film, so that a resin film portion that is to form an end seal section at the upper part of the composite container is uncovered, and then

gazette-like folding the upper end portion of the tubular resin film while the paper board remains attached thereto.

(16) The composite container according to any of (1) to (14) above, which is manufactured by

using a horizontal Form-Fill-Seal machine in which the resin film is unwound from a film roll, and shaped into a tube in the horizontal direction, and center-sealed, and then an upstream or downstream end of each pitch is sealed and cut to manufacture a pillow bag;

overlapping and at least partially bonding, for each pitch, a sheet-shaped paper board to an outer peripheral surface of the tubular resin film, so that a resin film portion that is to form an end seal section at the upper part of the composite container is uncovered, and then

gazette-like folding while the resin film and the paper board remain attached to each other.

(17) The composite container according to any of (1) to (14) above, which is manufactured by folding in a tubular shape a sheet-shaped composite sheet in which a paper board is attached to a resin film, the composite sheet being formed in a developed view shape such that when the paper board is folded, a tubular body portion and an end portion in a gable top shape at one end of the body portion are formed, and also being such that the resin film protrudes from the end portion of the paper board where a gazette portion is to be formed to form an end seal section when the paper board is folded and also protrudes from the other end portion of the paper board to form, at the time of end sealing, a container bottom surface which is not covered by the paper board, then center-sealing the composite sheet so that the resin film is in a tubular shape in a machine direction, gazette-like folding a portion of the resin film that is to form a container bottom surface and a composite sheet portion that is to form a container gable top portion while the resin film and the paper board remain attached to each other, and then end-sealing the protruded resin film.

(18) The composite container according to any of (1) to (14) above, which is manufactured by folding in a tubular shape a continuous composite sheet in which paper boards are attached to a resin film, the composite sheet being formed in a developed view shape such that when the paper board is folded, a tubular body portion and an end portion in a gable top shape at one end of the body portion are formed, and also being such that the resin film protrudes from the end portion of the paper board where a gazette portion is to be formed to form an end seal section when the paper board is folded and also protrudes from the other end portion of the paper board to form, at the time of end sealing, a container bottom surface which is not covered by the paper board, then center-sealing the composite sheet such that the resin film is in a tubular shape in a machine direction, gazette-like folding a portion of the resin film that is to form a container bottom surface and a composite sheet portion that is to form a container gable top portion while the resin film and the paper board remain attached to each other, and then end-sealing the protruded resin film.

(19) A package body in which the composite container according to any one of (1) to (18) above is filled with contents.

(20) A method for manufacturing a composite container,

the method comprising:

using a vertical Form-Fill-Seal machine in which a resin film is unwound from a film roll, and shaped into a tube in a vertical direction, and center-sealed, and then upper and lower ends of each pitch are sealed and cut to manufacture a pillow bag,

overlapping and at least partially bonding, for each pitch, a sheet-shaped paper board to an outer peripheral surface of the tubular resin film, so that a resin film portion that is to form an end seal section at the upper part of the composite container is uncovered, and then

gazette-like folding an upper end portion of the tubular resin film while the paper board remains attached thereto.

(21) A method for manufacturing a composite container, the method comprising:

using a horizontal Form-Fill-Seal machine in which a resin film is unwound from a film roll, and shaped into a tube in a horizontal direction, and center-sealed, and an upstream or downstream end of each pitch is sealed and cut to manufacture a pillow bag,

overlapping and at least partially bonding, for each pitch, a sheet-shaped paper board to an outer peripheral surface of the tubular resin film, so that a resin film portion that is to form an end seal section at an upper part of the composite container is uncovered, and then

gazette-like folding while the resin film and the paper board remain attached to each other.

(22) A method for manufacturing a composite container,

the method comprising:

folding in a tubular shape a sheet-shaped composite sheet in which a paper board is attached to a resin film, the composite sheet being formed in a developed view shape such that when the paper board is folded, a tubular body portion and an end portion in a gable top shape at one end of the body portion are formed, and also being such that the resin film protrudes from the end portion of the paper board where a gazette portion is to be formed to form an end seal section when the paper board is folded and also protrudes from the other end portion of the paper board to form, at the time of end sealing, a container bottom surface which is not covered by the paper board, then center-sealing the composite sheet such that the resin film is in a tubular shape in a machine direction, gazette-like folding a portion of the resin film that is to form a container bottom surface and a composite sheet portion that is to form a container gable top portion while the resin film and the paper board remain attached to each other, and then end-sealing the protruding resin film.

(23) A method for manufacturing a composite container,

the method comprising:

folding in a tubular shape a continuous composite sheet in which paper boards are attached to a resin film, the composite sheet being formed in a developed view shape such that when the paper board is folded, a tubular body portion and an end portion in a gable top shape at one end of the body portion are formed, and also being such that the resin film protrudes from the end portion of the paper board where a gazette portion is to be formed to form an end seal section when the paper board is folded and also protrudes from the other end portion of the paper board to form, at the time of end sealing, a container bottom surface which is not covered by the paper board, then center-sealing the composite sheet such that the resin film is in a tubular shape in a machine direction, gazette-like folding a portion of the resin film that is to form a container bottom surface and a composite sheet portion that is to form a container gable top portion while the resin film and the paper board remain attached to each other, and then end-sealing the protruding resin film.

The present invention can provide a composite container, as represented by a composite container which has a gas barrier property, an anti-moisture property, a shape retaining property, an anti-shock property, an easy-to-open property, and a resealing function, can be easily opened, and facilitates the extraction of the contents, and in which a paper board and a resin film are integrated.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an example of the composite container in accordance with the present invention.

FIG. 2 shows an example of a state in which the end seal section at the upper part of the composite container in accordance with the present invention is cut off and a spout is formed.

FIG. 3 shows an example in which a vertical notch and a transverse notch are formed in the end sealing portion of the resin film at the upper part of the composite container in accordance with the present invention.

FIG. 4(A) shows another example of the composite container in accordance with the present invention, and FIG. 4(B) shows an example of a state in which a notch is provided in the bottom of the body portion of the composite container in accordance with the present invention.

FIG. 5 shows a configuration example of the body portion cross section of the composite container in accordance with the present invention.

FIG. 6 shows an example of the cross section of the lower portion of the container in a case in which the composite container in accordance with the present invention is filled with lightweight contents.

FIG. 7 shows an example of the cross section of the lower portion of the container in a case in which the composite container in accordance with the present invention is filled with heavy contents.

FIG. 8 is an upper view of the conventional gable top type container.

FIG. 9 is an upper view of an exemplary composite container in accordance with the present invention.

FIG. 10(A) shows an example of the cross-sectional structure of the heat seal section of the gazette portion of the composite container in accordance with the present invention, and FIG. 10(B) shows another example of the cross-sectional structure of the heat seal section of the gazette portion of the composite container in accordance with the present invention.

FIG. 11 shows an example of a state in which a spout is formed by peeling the sealed portion of the end seal section at the top part of the composite container in accordance with the present invention.

FIG. 12 is a graph showing the result in Test Example 1 confirming that the composite container in accordance with the present invention is provided with an anti-moisture property.

FIG. 13 is a graph showing the result in Test Example 2 confirming that the composite container in accordance with the present invention is provided with an anti-moisture property.

BEST MODE FOR CARRYING OUT THE INVENTION

The present invention will be described below in greater detail with reference to the appended drawings.

The composite container in accordance with the present invention has a gable top shape in which a paper board is attached to the outer peripheral surface of a pillow type bag constituted by a resin film and having an end seal section and a center seal section. As shown in FIG. 1, the paper board is attached to the outer peripheral surface of the resin film in at least the body portion of the composite container. Further, in the upper part of the composite container, the resin film and the paper board are gazette-like folded while being attached to each other in such a manner that the end portion of the resin film protrudes from the end portion of the paper board, and the end portion of the resin film forms the end seal section. The inner peripheral surface of the paper board of the composite container is attached at the entire surface or part thereof to the resin film below the end seal section protruding from the end portion of the paper board.

The present invention has the abovementioned basic configuration, but there are two embodiments of the structure for extracting the contents.

In the structure of the first embodiment, by cutting off the end seal section, it is possible to draw out the portion of the paper shape that has been gazette-like folded, thereby forming a spout for extracting the contents.

In the structure of the second embodiment, sealing in the end seal section is performed through an easy-to-open resin layer or an easy-to-open resin film, and when the portion of the paper board that has been gazette-like folded is drawn out, a portion sealed by the easy-to-open resin layer or the easy-to-open resin film of the end seal section of the gazette portion is peeled off, thereby forming a spout for extracting the contents.

Initially, the first embodiment is described.

As shown in FIG. 2, where at least either of the left and right end portions of the end seal section is cut off in the end seal section of the resin film protruding from the end portion of the paper board in the upper part of the composite container, the portion of the paper board that has been gazette-like folded can be drawn out and a spout for extracting the contents can be formed. In this case, since the paper board and the resin film in the upper part of the composite container having a gable top shape are attached together, where the gazette-like folded paper board is drawn out, the resin film is also drawn out integrally therewith, the composite container is opened, and the spout is formed.

Thus, by contrast with the conventional gable top type beverage container that is opened by interface peeling off a sealing layer, the composite container in accordance with the present invention is opened by cutting off at least part of the end seal section of the resin film protruding from the paper board at the upper part of the composite container. It is not necessary to remove the entire end seal section as in a typical flexible packaging material, and in the case of the composite container shown in FIG. 2, the spout of the composite container can be formed by cutting off the end seal section at one side with respect to the center seal section on the end seal section as a center. Further, in the composite container such that the cross-section of the body potion of the composite container has a rectangular shape, rather than a substantially square shape, the spout of the composite container can be formed by cutting off at least either of the left and right end portion of the end seal section.

As indicted hereinabove, in the composite container in accordance with the present invention, the spout is formed by cutting off part of the end seal section at the upper part of the container. Therefore, it is preferred that a vertical notch and a transverse notch be formed in the end seal section of the resin film at the upper part of the composite container (see FIG. 3). As a result, the end seal section can be easily cut off by hand, without using a tool such as scissors.

Furthermore, at the time of opening from a transverse notch, the upper end portion (side) of the paper board below the end seal section demonstrates the effect of a guide that prevents meandering cutting toward the lower part of the container. For such guide function to be demonstrated effectively, it is preferred that the end portion of the paper board at the upper part of the composite container be attached to the resin film in the vicinity of the end seal section of the resin film. The distance between the paper board end portion and the end seal section at the upper part of the composite container is not particularly limited, but where this distance is about 2 mm to 5 mm, the guide function can be effectively demonstrated by the upper end portion of the paper board. The transverse notch is preferably provided on the end seal section on the paper board side.

At the time of opening from the vertical notch, the center seal section on the end seal section demonstrates the effect of a guide that prevents meandering toward the non-opening direction. From this standpoint, it is preferred that the vertical notch be provided in the vicinity of the center seal section on the end seal section of the resin film.

The second embodiment is described hereinbelow.

In the present embodiment an easy-to-open resin layer is coated, or an easy-to-open resin film is laminated on the inner surface of the resin film forming at least the end seal section. FIG. 10 shows the cross section of the end seal section in the case in which such resin film is gazette-like folded.

A resin film 64 is gazette-like folded at both sides to obtain a four-layer fold and form a gazette portion 84. The inner side of the resin film is coated with an easy-to-open resin layer or laminated with an easy-to-open resin film, and an easy-to-open seal section 82 is formed. FIG. 10(A) shows an example of the container in accordance with the present invention in which the outer surface of the resin film is also coated with an easy-to-open resin layer or laminated with an easy-to-open resin film, and an easy-to-open bonding section 83 is formed in the gazette portion.

FIG. 10(B) shows another example of the container in accordance with the present invention in which the outer surface of the resin film is neither coated with an easy-to-open resin layer nor laminated with an easy-to-open resin film. Therefore, the easy-to-open bonding section 83 such as shown in FIG. 10(A) is not formed.

Forming the easy-to-open bonding section 83 such as shown in FIG. 10(A) is not a mandatory condition of the present invention, but is preferred from the standpoint of external appearance of the container.

The spout for extracting the contents can be formed by peeling off the easy-to-open seal section 82 by a tensile stress when the portion of the paper board that has been gazette-like folded is drawn out.

FIG. 11 shows a state in which the spout for extracting the contents from the container of the type shown in FIG. 10(B) is formed by peeling off the easy-to-open seal section 82.

In this case, the opening process is facilitated by using the following configuration (1) or (2).

(1) A parting agent is coated at a position in the upper half of the center portion, as viewed from the box side surface, between the easy-to-open resin layer and easy-to-open resin film of the end seal section positioned in the gazette portion, thereby obtaining a non-sealed state, and the easy-to-open resin layer or easy-to-open resin film can be peeled off and opened by pushing with a finger at this position.

(2) When the end sealing portion is formed, the sealing is performed by using an end sealing bar of a shape such that a non-sealed portion is formed at a position in the upper half of the center portion, as viewed from the box side surface, and the easy-to-open resin layer or easy-to-open resin film can be peeled off and opened by pushing with a finger against the non-sealed portion.

In the present embodiment, the end seal section of the resin film remains intact and is not cut off. As a result, the anti-moisture property after opening is superior to that in the first embodiment.

Further, the configuration used in the second embodiment may be added to that of the first embodiment and opening methods of two types can be selected.

In the composite container in accordance with the present invention, since the spout is formed in the above-described manner, the contents can be extracted by merely tilting the main body portion by hand. Therefore, the hand is not soiled when the contents are extracted, and even when the contents are a fluid, such as a liquid or granules, the contents can be prevented from scattering and the extracted amount can be adjusted in a simple manner by adjusting the spout shape or the tilting degree of the main body.

The body portion of the composite container preferably has a quadrangular cross section, more preferably a square or rectangular (oblong) cross section. As a result, the body portion of the main body of the composite container has an angular columnar shape. Therefore, it can be easily taken by hand and handleability thereof is improved. For this purpose, it is also preferred that a fold line for forming the outer shape of the main body be provided in the paper board of the body portion of the composite container.

The composite container in accordance with the present invention can be closed by folding the paper board, in which the spout has been drawn out, back again in a gazette shape (see FIG. 2). In this case, even though no component such as a zipper is specifically provided in the opening of the composite container in accordance with the present invention, a good resealing function can be demonstrated due to the rigidity and elasticity of the paper board attached to the main body. It is particularly preferred that a fold line (bending ruled line) for gazette-like folding be provided in the paper board. As a result of providing the fold line, it is possible to facilitate further the formation of the spout of the composite container and demonstrate a good resealing function.

Further, at the bottom of the composite container, the paper board may or may not be attached to the end seal section of the pillow type bag constituted by the resin film, but from the standpoint of industrial production, it is preferred that the paper board be not attached. Further, since the amount of paper board required for producing the composite container can be reduced, contribution is made to environmental protection and decrease in the production cost resulting from the decrease in the material used. In this case, the end portion of the paper board constituting the side surface (body portion) of the composite container serves as a structure supporting the composite container, and a bottom surface from the paper board is not formed at the bottom of the composite container. Further, in a case in which the paper board and the end seal section of the resin film are not attached together at the bottom of the composite container, the configuration is preferred in which the end seal section of the resin film is accommodated inside the composite container, without protruding from the end portion of the paper board.

Further, according to one aspect of the composite container in accordance with the present invention, it is preferred that the end portion of the paper board abut against the base of the center seal section of the pillow type bag and that the center seal section be exposed on the outer peripheral surface of the paper board from between the end portion of the paper board, which abuts against the base of the center seal section, and the other end portion (see FIG. 4(A)). As a result when the composite container in accordance with the present invention is manufactured, alignment of the pillow type bag and the paper board is facilitated and therefore industrial productivity can be increased.

However, in a state in which the center seal section is wrapped around the lower side of the paper board at the bottom of the composite container, the center seal section on the outer peripheral surface of the composite container causes at the bottom of the composite container repulsion or a step induced by the thickness of the center seal section. For this reason, the self-standing ability of the container main body is inhibited when the composite container is stored after being opened, or when the container is temporarily placed to form the spout at the time the contents is extracted, and the container can tumble, thereby scattering the contents. In particular, where the container is filled with a comparatively lightweight contents, the center seal section at the bottom of the composite container cannot be pressed against the ground surface, and therefore the self-standing ability of the container is degraded.

In such a case, it is preferred that a cut or a notch with a width equal to or greater than the center seal width be provided in the paper board at the lower portion of the side surface of the composite container that is covered by the center seal section (see FIG. 4(B)). As a result, the repulsion or the formation of a step caused by the thickness of the center seal section can be avoided in a free-standing state of the composite container.

FIG. 5 is a cross-sectional view of a configuration example of the body portion of the composite container in accordance with the present invention.

FIG. 5(A) is a cross-sectional view of the body portion of the composite container shown in FIG. 4 and represents a state in which the center seal section of the pillow type bag constituted by the resin film is exposed at the outer surface of the composite container from the abutment portion of the paper board on the outer periphery of the composite container. FIG. 5(B) shows a state in which one end portion of the paper board abuts against the base of the center seal section of the pillow type bag, and the other end portion of the paper board is attached so as to hide the center seal section. In this case, the position of the end portion of the paper board that covers the center seal section of the pillow type bag may be aligned with the end portion of the center seal section, or may be formed longer than the end portion of the center seal section, as shown in FIG. 5(B).

FIGS. 5(C) to 5(H) represent a state in which the center seal section of the pillow type bag is confined inside the outer surface of the composite container, which is constituted by the paper board, and not exposed on the peripheral surface of the composite container.

FIG. 5(C) is a cross-sectional view of the composite container body portion in a state in which the abutment portion of the paper board overlaps the center seal section of the pillow type bag. Further, FIG. 5(D) represents a state in which the abutment portion of the paper board is shifted with respect to the center seal section of the pillow type bag. FIG. 5(E) represents a state in which the center seal section of the pillow type bag is confined inside the composite container and overlaps the end portion of the paper board. FIG. 5(F) represents a state in which the center seal section of the pillow type bag is shifted from the transversely center portion of the side surface of the composite container.

Further, FIG. 5(G) represents a state in which the positions of the center seal section of the pillow type bag and the abutment portion of the paper board are shifted with respect to each other and both positions are also shifted from the transversely center portion of the side surface of the composite container. FIGS. 5(H) and 5(I) represent a state in which the center seal section of the pillow type bag and the abutment portion of the paper board overlap and are shifted from the transversely center portion of the side surface of the composite container.

In the case of the composite container of the type shown in FIGS. 5(A) and 5(B), the center seal section is wrapped around the lower side of the paper board at the bottom of the composite container. Therefore, as mentioned hereinabove, it is preferred that a cut or a notch with a width equal to or greater than the center seal width be provided in the paper board at the lower portion of the side surface of the composite container that is covered by the center seal section (see FIG. 4(B)).

Further, in the case of comparatively lightweight contents, it is preferred that a non-attached portion be provided between the paper board and the resin film in a portion constituting the body portion of the composite container. FIG. 6 is a cross-sectional view illustrating an example in which the paper board is not attached to the outer peripheral surface of the resin film at the bottom of the composite container, and a non-attached portion is provided between the paper board and the resin film in the body portion of the composite container. In the case of lightweight contents, since the non-attached portion is provided between the paper board and the resin film, the pillow type bag inside the composite container is in the raised bottom state, the repulsive force of the end seal section acting in the direction of tilting the composite container can be released and the self-standing property of the composite container can be effectively ensured.

Further, as shown in FIG. 7, where the contents are a heavy matter, there is no need to provide the non-attached portion between the resin film and the paper board in the portion constituting the body portion of the composite container. In this case, the composite container self-stands on the entire bottom surface (bottom of the pillow type bag) of the composite container. Therefore, the gravity-caused damage of the paper board can be inhibited and stability can be ensured. The paper board enhances the stability of the self-standing state of the composite container.

Thus, in the composite container in accordance with the present invention, by setting, as appropriate, the bonding range of the paper board and the resin film according to the weight of the contents, it is possible to ensure high self-standing stability and container strength.

According to another aspect of the composite container in accordance with the present invention, it is preferred that the end portion of the paper board abut against the base of the center seal section of the pillow type bag, the center seal section overlap the outer peripheral surface of the end portion of the paper board, and the end portion, which is on the side opposite that of the end portion of the paper board that abuts against the base, cover the center seal section. As a result, the center seal section of the pillow type bag is not exposed on the surface of the paper board. Therefore, the printed surface of the paper board is not hidden by the center seal section, thereby enhancing the aesthetics of the composite container. For example, FIG. 1 shows an example in which the paper board covers the center seal section and the center seal section is not exposed on the surface of the composite container.

Further, as mentioned hereinabove, in the composite container in accordance with the present invention, the cross section of the body portion can have not only a square shape, but also a quadrangular, such as rectangular, shape. Therefore, the freedom of design is increased. In the conventional gable top type container, which is typical for a beverage pack, paper is gazette-like folded to seal an end. Therefore, the gap between the seal surfaces should be minimized by obtaining a state in which the apexes of the gazette that has been folded inward from the left and right sides are mated with each other (see FIG. 8(A)). This is because unless such a state is obtained, a gap appears between the portions of paper that face each other outside the portion folded in the gazette, and sealing in order to eliminate and hermetically close the gap is very difficult to perform. This is why the cross section of the container is restricted to a substantially square shape (see FIG. 8(B)).

By contrast, in the composite container in accordance with the present invention, portions of the resin film, to which the paper board has not been attached, are sealed (end seal section at the upper part of the composite container). Therefore, even when the cross-section of the body portion of the composite container is not of a square shape, the gap between the sealed surfaces is only of the size of the thickness of the folded resin film. Further, since the resin film is flexible, the gap is easy to fill, and hermetic sealing can be performed by casting a sealant. Therefore, even when the cross section of the body portion of the composite container is not of a square shape, as in the gazette packages, which are presently available typical flexible packages produced from a resin film, stable sealing ability can be obtained and the degree of freedom of design of the composite containers can be increased (see FIG. 9).

The aforementioned resin may be synthetic or plant-derived. By providing the resin film with a gas barrier property, it is possible to prevent the contents prior to sealing from oxidation and moisture absorption.

For example, OPP, CPP, PET, VM-PET can be advantageously used for the synthetic resin film. For example, PLA and PVA can be advantageously used for the plant-derived resin film.

The thickness of such resins films is not particularly limited. For example, a film with a thickness of about 30 μm to 80 μm can be advantageously used.

The contents to be accommodated in the composite container in accordance with the present invention is not particularly limited, and food, confectionary, beverages, and also detergents and drugs can be accommodated in solid, granular, or liquid form. For example, cereals such as corn flakes, snacks, and pet food can be accommodated.

Further, in the composite container in accordance with the present invention, the paper board and the resin film can be easily separated by bonding the paper board and the resin film with an easy-to-peel adhesive or by applying an adhesive in a spot-like fashion, and the trash can be easily separated and collected.

The composite container in accordance with the present invention can be manufactured using a Form-Fill-Seal machine that has been used for manufacturing the conventional pillow type bags. The Form-Fill-Seal machine to be used may be a vertical Form-Fill-Seal machine or a horizontal Form-Fill-Seal.

When a vertical Form-Fill-Seal machine is used, the composite container can be manufactured by: using a vertical Form-Fill-Seal machine in which the resin film is unwound from a film roll, shaped into a tube in the vertical direction, and center-sealed, and upper and lower ends of each pitch are sealed and cut to manufacture a pillow bag; overlapping and at least partially bonding, for each pitch, a sheet-shaped paper board to an outer peripheral surface of the tubular resin film, so that a resin film portion that is to form an end seal section at the upper part of the composite container is uncovered; and then gazette-like folding the upper end portion of the tubular resin film while the paper board remains attached thereto.

When a horizontal Form-Fill-Seal machine is used, the composite container can be manufactured by: using a horizontal Form-Fill-Seal machine in which the resin film is unwound from a film roll, shaped into a tube in the horizontal direction, and center-sealed, and an upstream or downstream end of each pitch is sealed and cut to manufacture a pillow bag; overlapping and at least partially bonding, for each pitch, a sheet-shaped paper board to an outer peripheral surface of the tubular resin film, so that a resin film portion that is to form an end seal section at the upper part of the composite container is uncovered; and then gazette-like folding while the resin film and the paper board remain attached to each other.

Where the composite container in accordance with the present invention is fabricated using either the vertical Form-Fill-Seal machine or the horizontal Form-Fill-Seal machine, the center seal section of the pillow type bag constituted by a resin film may overlap with a shift in any direction from the central portion of the rear surface of the paper board. As a result, as shown in FIG. 5(D) or 5(F), it is possible to fabricate a composite container in a state in which the abutment portion of the paper board and the center seal section of the pillow type bag constituted by a resin film are shifted.

Thus, where a composite container is formed such that the abutment portion of the paper board is shifted from the transversely central portion of the side surface of the composite container when the center seal section of the pillow type bag is shifted from the central portion of the paper board, the configuration shown in FIG. 5(D) is obtained, and where a composite container is formed such that the abutment portion of the paper board is positioned in the transversely central portion of the side surface of the composite container, the configuration shown in FIG. 5(F) is obtained. A composite container may be also formed such that the abutment portion of the paper board is shifted from the transversely central portion of the side surface of the composite container, and the center seal section of the pillow type bag constituted by a resin film is also shifted from the transversely central portion of the side surface of the composite container, as shown in FIG. 5(G). Furthermore, a composite container may be also formed such that the abutment portion of the paper board and the center seal section of the pillow type bag constituted by a resin film are shifted from the transversely central portion of the side surface of the composite container in a state of overlapping, as shown in FIGS. 5(H) and 5(I).

Explained hereinabove is a method for manufacturing a composite container by unwinding a resin film from a film roll and using a vertical Form-Fill-Seal machine or a horizontal Form-Fill-Seal machine, but a composite container can be also manufactured by using a sheet-shaped composite film in which a sheet-shaped paper board is attached by the entire surface or partially to a sheet-shaped resin film.

With such a method, initially a composite sheet is obtained by attaching one paper board to one resin film. In this case, when the paper board is folded in the same manner as in the case of manufacturing a composite container with a pillow machine, a developed view shape is obtained such that a tubular body portion and an end portion in a gable top shape at one end of the body portion are formed. Further, the resin film protrudes from the end portion of the paper board where a gazette portion is to be formed to form an end seal section when the paper board is folded, and also protrudes from the other end portion of the paper board to form, upon end sealing, a container bottom surface which is not covered by the paper board.

Such a composite sheet is folded in a tubular shape and center-sealed such that the resin film has a tubular shape in a machine direction. Then, a composite container can be manufactured by gazette-like folding a portion of the resin film that is to form a container bottom surface and a composite sheet portion that is to form a container gable top portion, while the resin film and the paper board remain attached to each other, and then end-sealing the protruding resin film.

In the above-described process, a composite sheet is used in which one paper board is attached to one resin film, but composite containers can be also continuously manufactured by supplying to a vertical Form-Fill-Seal machine or a horizontal Form-Fill-Seal machine a composite sheet in which a large number of sheet-shaped paper boards are attached to an elongated resin film. In this case, a composite container can be manufactured by folding the composite sheet in a tubular shape and center-sealing the composite sheet such that the resin film has a tubular shape in a machine direction, gazette-like folding a portion of the resin film that is to form a container bottom surface and a composite sheet portion that is to form a container gable top portion, while the resin film and the paper board remain attached to each other, and then end-sealing the protruding resin film and cutting an end seal section.

Described below are the test results confirming that the composite container in accordance with the present invention demonstrates good anti-moisture property because the spout is closed after the container has been opened.

TEST EXAMPLE 1

Two composite containers such as shown in FIG. 4(B) were fabricated using the abovementioned vertical Form-Fill-Seal machine. In the composite container, the center seal section of a pillow type bag was exposed from the end portion of a paper board on the outer peripheral surface of the composite container, and a cut was provided in the portion of the paper board that was covered by the exposed center seal section at the bottom of the composite container. A white chipboard was used as the paper board, and PET #12/VMPET #12/LLDPE #50 was used as the resin film. Each composite container had a weight of 40.00 g, and the capacity of the body portion of the composite container was 80 mm□80 mm□150 mm. The height of the gable top portion at the upper part of each composite container was 30 mm.

Only one side, with respect to the center seal section as a center, was opened in the end seal portion at the upper part of the fabricated composite containers, and a spout was formed by pulling out the gazette-like folded portion. A total of 100.00 g (Gross 140.00 g) of A-type silica gel was charged from the spout.

The composite container in which the formed spout remained intact was taken as a container [a], and the composite container in which the spout was again gazette-like folded back was taken as a container [b], and temporal changes in the container weight were measured. The results are shown in Table 1, and a graph showing the anti-moisture effect inspection data is shown in FIG. 12.

TABLE 1 (g) Elapsed Weight of Contents [a] − [b] [b′]/[a′] × Days ([a]) [b] ([a′] − [b′]) 100 (100.00 g) (100.00 g) 0.00 g -% (0 g) (0 g) 1 100.84 g 100.24 g 0.60 g 28.57% (0.84 g) (0.24 g) 2 101.43 g 100.28 g 1.15 g 19.58% (1.43 g) (0.28 g) 3 102.33 g 100.46 g 1.87 g 19.74% (2.33 g) (0.46 g) 4 102.72 g 100.58 g 2.14 g 21.32% (2.72 g) (0.58 g) 5 103.14 g 100.74 g 2.40 g 23.57% (3.14 g) (0.74 g) 6 103.54 g 100.88 g 2.66 g 24.86% (3.54 g) (0.88 g) 7 104.10 g 100.98 g 3.12 g 23.90% (4.10 g) (0.98 g) 8 104.57 g 101.13 g 3.44 g 24.73% (4.57 g) (1.13 g) 9 105.58 g 101.53 g 4.05 g 27.42% (5.58 g) (1.53 g) 10 105.82 g 101.51 g 4.31 g 25.95% (5.82 g) (1.51 g) 11 106.28 g 101.74 g 4.54 g 27.71% (6.28 g) (1.74 g) 12 106.61 g 101.92 g 4.69 g 29.05% (6.61 g) (1.92 g) 13 107.03 g 102.18 g 4.85 g 31.01% (7.03 g) (2.18 g) 14 107.31 g 102.20 g 5.11 g 30.10% (7.31 g) (2.20 g) 15 107.82 g 102.42 g 5.40 g 30.95% (7.82 g) (2.42 g) indicates data missing or illegible when filed

As shown in Table 1 and FIG. 12, it was confirmed that in the composite container in accordance with the present invention, the anti-moisture effect could be greatly improved by folding back the spout again, by comparison with the case in which the formed spout remained intact.

TEST EXAMPLE 2

Two composite containers such as shown in FIG. 4(B) were fabricated in exactly the same manner as in Test Example 1.

By contrast with Test Example 1, the end seal section at the upper part of the composite containers was entirely cut off. Then the upper portion of the composite containers was entirely opened by drawing out the gazette-like folded portions of the left and right side of the upper portion of the composite container. A total of 100.00 g (Gross 140.00 g) of silica gel was charged from the upper portion of the entirely opened composite container.

The composite container in which the spout remained entirely opened was taken as a container [c], and the composite container in which the portions drawn out at the left and right sides were again gazette-like folded back was taken as a container [d], and temporal changes in the container weight were measured. The results are shown in Table 2, and a graph showing the anti-moisture effect inspection data is shown in FIG. 13.

TABLE 2 Weight Weight of Contents (g) Difference Elapsed Gable top/Open [c] Gable top/Close [d] [c] − [d] [d′]/[c′] × Days (Increase in Weight [c′]) = % (Increase in Weight [d′]) = % ([c′] − [d′]) 100 100.00 g 100.00 g 0.00 g -% (0 g) (0 g) 1 105.46 g 100.26 g 5.20 g 4.76% (5.46 g) (0.26 g) 2 109.09 g 100.59 g 8.50 g 6.49% (9.09 g) (0.59 g) 3 112.42 g 100.93 g 11.49 g 7.49% (12.42 g) (0.93 g) 4 115.44 g 101.50 g 13.94 g 9.72% (15.44 g) (1.50 g) 5 117.15 g 102.00 g 15.15 g 11.66% (17.15 g) (2.00 g) 6 118.15 g 102.18 g 15.97 g 12.01% (18.15 g) (2.18 g) 7 119.33 g 102.41 g 16.92 g 12.47% (19.33 g) (2.41 g) 8 120.60 g 102.80 g 17.80 g 13.59% (20.60 g) (2.80 g) 9 121.84 g 103.14 g 18.70 g 14.38% (21.84 g) (3.14 g) 10 123.75 g 103.76 g 19.99 g 15.83% (23.75 g) (3.76 g) 11 124.31 g 103.96 g 20.35 g 16.29% (24.31 g) (3.96 g) 12 124.61 g 104.09 g 20.52 g 16.62% (24.61 g) (4.09 g) 13 124.65 g 104.31 g 20.34 g 17.48% (24.65 g) (4.31 g) 14 124.28 g 104.42 g 19.86 g 18.20% (24.28 g) (4.42 g) 15 124.36 g 104.74 g 19.62 g 19.46% (24.36 g) (4.74 g)

As shown in Table 2 and FIG. 13, it was confirmed that in the composite container in accordance with the present invention, even when the upper portion of the composite container was entirely opened by cutting off the upper end seal section and drawing out the gazette-like folded portions on the left and right side, the anti-moisture effect could be greatly improved by again gazette-like folding back the portions on the left and right side by comparison with the case in which the container remained entirely opened.

EXPLANATION OF REFERENCE NUMERALS

11 paper board

12 end seal section of resin film

13 gazette-like folded upper portion of composite container

14 unsealed resin film portion

31 vertical notch

32 transverse notch

41 cut or notch

61 paper board

62 end seal section of resin film

63 center seal section of resin film

64 resin film

65 portion in which paper board and resin film are attached together

71 paper board

72 end seal section of resin film

73 center seal section of resin film

74 resin film

81 gap

81 minimized gap

82 easy-to-open seal section

83 easy-to-peel attached section

84 gazette section

85 gazette-like folded deepest section

91 portion hermetically sealed by casting, e.g., a sealant

Claims

1. A composite container having a gable top shape in which a paper board is attached to an outer peripheral surface of a pillow type bag constituted by a resin film and having an end seal section and a center seal section, wherein

the paper board is attached to the resin film in at least a body portion of the composite container;

in an upper part of the composite container, the resin film and the paper board are gazette-like folded while being attached to each other in such a manner that an end portion of the resin film protrudes from an end portion of the paper board, and the end portion of the resin film forms the end seal section; and

an inner peripheral surface of the paper board of the composite container is attached at an entire surface or part thereof to the resin film below the end seal section protruding from the end portion of the paper board.

2. The composite container according to claim 1 above, wherein a spout for extracting container contents can be formed by cutting off at least one of left and right end portions of the end seal section and drawing out a portion that has been gazette-like folded.

3. The composite container according to claim 1, wherein

at least an inner surface of the resin film of the end seal section is sealed by an easy-to-open resin layer or an easy-to-open resin film, and

a spout for extracting the contents can be formed by peeling off a portion sealed by the easy-to-open resin layer or the easy-to-open resin film of the end seal section of a gazette portion, and drawing out a portion that has been gazette-like folded.

4. The composite container according to claim 1,wherein after the composite container has been opened, a portion forming the spout can be gazette-like folded again.

5. The composite container according to claim 1, wherein a body portion cross section of the composite container has a quadrangular shape.

6. The composite container according to claim 1, wherein

in a bottom portion of the composite container, the paper board is not attached to the outer peripheral surface including the end seal section of the pillow type bag.

7. The composite container according to claim 1, wherein

a fold line for gazette-like folding is provided in the paper board.

8. The composite container according to claim 1, wherein

a fold line for forming an outer shape of the main body of the composite container is provided in the paper board.

9. The composite container according to claim 1, wherein

the end portion of the paper board abuts against a base of the center seal section, and the center seal section is exposed on the outer peripheral surface of the paper board from between the end portion of the paper board and the other end portion of the paper board.

10. The composite container according to claim 1, wherein one end portion of the paper board abuts against a base of the center seal section, the center seal section overlaps the outer peripheral surface of this end portion, and the other end portion of the paper board covers the center seal section.

11. The composite container according to claim 1, wherein a notch or a cut with a width equal to or greater than the center seal width is provided in the paper board at the bottom of the composite container.

12. The composite container according to claim 1, wherein a non-attached portion is present between the paper board and the resin film in a portion constituting the body portion of the composite container.

13. The composite container according to claim 1 above, wherein the end seal section of the resin film at the upper part of the composite container has a vertical notch and a transverse notch and only part of the end seal section can be opened.

14. The composite container according to claim 1 above, wherein the paper board and the resin film of the composite container are attached such that the paper board and the resin film can be easily peeled off and separated.

15. The composite container according to claim 1 above, which is manufactured by

using a vertical Form-Fill-Seal machine in which the resin film is unwound from a film roll, and shaped into a tube in the vertical direction, and center-sealed, and then upper and lower ends of each pitch are sealed and cut to manufacture a pillow bag,

overlapping and at least partially bonding, for each pitch, a sheet-shaped paper board to an outer peripheral surface of the tubular resin film, so that a resin film portion that is to form an end seal section at the upper part of the composite container is uncovered, and then

gazette-like folding the upper end portion of the tubular resin film while the paper board remains attached thereto.

16. The composite container according to claim 1, which is manufactured by

using a horizontal Form-Fill-Seal machine in which the resin film is unwound from a film roll, and shaped into a tube in the horizontal direction, and center-sealed, and then an upstream or downstream end of each pitch is sealed and cut to manufacture a pillow bag;

overlapping and at least partially bonding, for each pitch, a sheet-shaped paper board to an outer peripheral surface of the tubular resin film, so that a resin film portion that is to form an end seal section at the upper part of the composite container is uncovered, and then

gazette-like folding while the resin film and the paper board remain attached to each other.

17. The composite container according to claim 1, which is manufactured by folding in a tubular shape a sheet-shaped composite sheet in which a paper board is attached to a resin film, the composite sheet being formed in a developed view shape such that when the paper board is folded, a tubular body portion and an end portion in a gable top shape at one end of the body portion are formed, and also being such that the resin film protrudes from the end portion of the paper board where a gazette portion is to be formed to form an end seal section when the paper board is folded and also protrudes from the other end portion of the paper board to form, at the time of end sealing, a container bottom surface which is not covered by the paper board, then center-sealing the composite sheet so that the resin film is in a tubular shape in a machine direction, gazette-like folding a portion of the resin film that is to form a container bottom surface and a composite sheet portion that is to form a container gable top portion while the resin film and the paper board remain attached to each other, and then end-sealing the protruded resin film.

18. The composite container according to claim 1, which is manufactured by folding in a tubular shape a continuous composite sheet in which paper boards are attached to a resin film, the composite sheet being formed in a developed view shape such that when the paper board is folded, a tubular body portion and an end portion in a gable top shape at one end of the body portion are formed, and also being such that the resin film protrudes from the end portion of the paper board where a gazette portion is to be formed to form an end seal section when the paper board is folded and also protrudes from the other end portion of the paper board to form, at the time of end sealing, a container bottom surface which is not covered by the paper board, then center-sealing the composite sheet such that the resin film is in a tubular shape in a machine direction, gazette-like folding a portion of the resin film that is to form a container bottom surface and a composite sheet portion that is to form a container gable top portion while the resin film and the paper board remain attached to each other, and then end-sealing the protruded resin film.

19. A package body in which the composite container according to claim 1 above is filled with contents.

20. A method for manufacturing a composite container,

the method comprising:

using a vertical Form-Fill-Seal machine in which a resin film is unwound from a film roll, and shaped into a tube in a vertical direction, and center-sealed, and then upper and lower ends of each pitch are sealed and cut to manufacture a pillow bag,

overlapping and at least partially bonding, for each pitch, a sheet-shaped paper board to an outer peripheral surface of the tubular resin film, so that a resin film portion that is to form an end seal section at the upper part of the composite container is uncovered, and then

gazette-like folding an upper end portion of the tubular resin film while the paper board remains attached thereto.

21. A method for manufacturing a composite container, the method comprising:

using a horizontal Form-Fill-Seal machine in which a resin film is unwound from a film roll, and shaped into a tube in a horizontal direction, and center-sealed, and an upstream or downstream end of each pitch is sealed and cut to manufacture a pillow bag,

overlapping and at least partially bonding, for each pitch, a sheet-shaped paper board to an outer peripheral surface of the tubular resin film, so that a resin film portion that is to form an end seal section at an upper part of the composite container is uncovered, and then

gazette-like folding while the resin film and the paper board remain attached to each other.

22. A method for manufacturing a composite container,

the method comprising:

folding in a tubular shape a sheet-shaped composite sheet in which a paper board is attached to a resin film, the composite sheet being formed in a developed view shape such that when the paper board is folded, a tubular body portion and an end portion in a gable top shape at one end of the body portion are formed, and also being such that the resin film protrudes from the end portion of the paper board where a gazette portion is to be formed to form an end seal section when the paper board is folded and also protrudes from the other end portion of the paper board to form, at the time of end sealing, a container bottom surface which is not covered by the paper board, then center-sealing the composite sheet such that the resin film is in a tubular shape in a machine direction, gazette-like folding a portion of the resin film that is to form a container bottom surface and a composite sheet portion that is to form a container gable top portion while the resin film and the paper board remain attached to each other, and then end-sealing the protruding resin film.

23. A method for manufacturing a composite container,

the method comprising:

folding in a tubular shape a continuous composite sheet in which paper boards are attached to a resin film, the composite sheet being formed in a developed view shape such that when the paper board is folded, a tubular body portion and an end portion in a gable top shape at one end of the body portion are formed, and also being such that the resin film protrudes from the end portion of the paper board where a gazette portion is to be formed to form an end seal section when the paper board is folded and also protrudes from the other end portion of the paper board to form, at the time of end sealing, a container bottom surface which is not covered by the paper board, then center-sealing the composite sheet such that the resin film is in a tubular shape in a machine direction, gazette-like folding a portion of the resin film that is to form a container bottom surface and a composite sheet portion that is to form a container gable top portion while the resin film and the paper board remain attached to each other, and then end-sealing the protruding resin film.