Composite container and method for manufacturing the same

Abstract

To reduce a resin amount and improve manufacturing efficiency by combining a resin skeleton and a paper cylindrical body, and satisfactory maintain a joint state between the resin skeleton and an upper end side part of the paper cylindrical body.SOLUTION: A composite container includes a storage part 10 which has a bottom surface 11 and a side surface 12 and an opened top surface 13, wherein the storage part 10 is composed of a resin assembly 20 and a paper cylindrical body 30, and the assembly 20 constitutes an outer edge part of the top surface 13, and includes an upper end side 31d part of the cylindrical body 30 and an upper skeleton body 23 joined from both sides of its inner surface and outer surface.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a composite container and a method for manufacturing a composite container. [Background technology]

[0002] In recent years, efforts have been made to reduce the amount of resin used in disposable containers in order to reduce the burden on the natural environment caused by plastic waste, including microplastics. Specific efforts include reducing the amount of resin used in plastic containers and replacing plastic products with paper products. In addition, composite containers that combine plastic containers with paper components have also been proposed.

[0003] For example, Patent Document 1 proposes a composite container that combines a resin container and a paper sleeve (reinforcing member). In this composite container, a thin-walled portion having a thickness of 0.01 mm to 0.09 mm is provided in the body of the resin container to reduce the amount of resin. However, when such a thin-walled portion is provided in the body, the body is easily deformed and cannot be gripped. Therefore, in this resin container, a flange portion connected to the body, a thick-walled portion connected to the flange portion in the body, and a protruding portion protruding radially outward from the thick-walled portion are provided, and the thin-walled portion is disposed on the bottom side of the thick-walled portion. Then, the body of the resin container is inserted into a cylindrical paper sleeve, and the sleeve is supported by the protruding portion, so that the resin container and the paper sleeve can be easily attached, and the rigidity of the resin container reduced by the thin-walled portion is reinforced by the sleeve. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2021-116122 A Summary of the Invention [Problem to be solved by the invention]

[0005] According to the composite container disclosed in the above Patent Document 1, the amount of resin in the body is greatly reduced by obtaining rigidity with the paper sleeve. However, the upper part of the body is provided with a thick part, and the bottom part is also made thicker than the thin part in order to maintain a certain strength. Therefore, the resin part is relatively large, and further reduction in the amount of resin used is required. Furthermore, in the above composite container, after preparing the resin container and the paper sleeve separately, the paper sleeve needs to be attached to the resin container. Therefore, the manufacturing process is complicated, and improvement in manufacturing efficiency is required. Furthermore, in the composite container disclosed in Patent Document 1, a protruding piece is provided at the upper end of the paper sleeve, and the protruding piece is folded to form an engagement part and attached to the upper end of the resin container. However, there is a risk that the paper sleeve will come off from the resin container even during use. Furthermore, when the composite container contains a liquid such as a beverage, moisture adheres to the upper end of the paper sleeve, and if the paper sleeve becomes soft, the paper sleeve may become more easily detached from the resin container.

[0006] Therefore, the object of the present invention is to provide a composite container and a manufacturing method thereof which can reduce the amount of resin and improve manufacturing efficiency by combining a resin framework with a paper tubular body, and which can maintain a good joint state between the resin framework and the top edge portion of the paper tubular body. [Means for solving the problem]

[0007] In order to solve the above problems, the composite container of the present invention comprises a storage section having a bottom and sides and an open top, the storage section being constructed using a resin framework and a paper tubular body, the framework comprising a top framework which forms the outer edge portion of the top and which joins the top edge portion of the tubular body from both its inner and outer sides, a bottom framework which forms the framework of the bottom, and a support part which is joined to the inner surface of a tubular paper face piece which forms the side and connects the bottom framework and the top framework, the support part being not provided on the outer surface of the paper face piece and being joined only to the inner surface of the paper face piece with respect to the side. The top frame body comprises an annular top frame body joined to the top edge portion and a flange portion protruding radially outward from the upper end of the top frame body, the lower surface of the flange portion being located higher than the top edge portion, the top frame body comprises an inner surface portion joined to the inner surface side of the top edge portion and an outer surface portion joined to the outer surface side of the top edge portion, the upper ends of the support portions are connected to the inner surface portion, the plate thickness of the outer surface portion becomes smaller from the flange portion side to the bottom surface side, and the portion on the outer surface of the top frame body that connects the lower end of the outer surface portion to the lower surface of the flange portion is inclined so as to be positioned radially outward as it extends upward. The plate thickness of the outer surface portion and the inner surface portion both becomes smaller from the flange portion side toward the bottom surface side, the lower end of the outer surface portion and the lower end of the inner surface portion are located at the same height, and the portion of the top edge portion sandwiched between the outer surface portion and the inner surface portion has a straight shape from top to bottom. do.

[0008] In the composite container according to the present invention, the cylindrical body is one or more The above The ends of the paper mask are joined together to form a tube. ,before It is preferable that one end edge and the other end edge of the paper face piece are joined to each other at the support portion.

[0009] In the composite container according to the present invention, the cylindrical body is provided with one or more polyolefin-based resin layers on the surface. The above It is preferable that the face piece is made of paper and the framework is made of polyolefin resin.

[0010] In order to solve the above problems, the manufacturing method of the composite container according to the present invention is a manufacturing method of a composite container having a bottom surface and side surfaces and a storage section with an open top surface, the storage section being constructed using a resin framework and a paper tubular body, the framework comprising a top framework body which forms the outer edge portion of the top surface and which joins the top edge portion of the tubular body from both its inner and outer surfaces, a bottom framework body which forms the framework of the bottom surface, and a cylindrical paper panel body which forms the side surfaces and which is joined to the inner surface of the panel and connects the bottom framework body to the top framework body. the top frame body has an annular top frame body joined to the top edge portion and a flange portion protruding radially outward from the upper end of the top frame body, the lower surface of the flange portion being located higher than the top edge portion, the top frame body has an inner surface portion joined to the inner surface side of the top edge portion and an outer surface portion joined to the outer surface side of the top edge portion, and the upper end of the support portion is connected to the inner surface portion, a plate thickness of the outer surface portion becomes smaller from the flange portion side toward the bottom surface side, and a portion of the outer surface of the top frame body connecting a lower end of the outer surface portion and the lower surface of the flange portion is inclined so as to be positioned radially outward as it extends upward; The plate thickness of the outer surface portion and the inner surface portion both becomes smaller from the flange portion side to the bottom surface side, and the lower end of the outer surface portion and the lower end of the inner surface portion are located at the same height, and the portion of the top edge portion sandwiched between the outer surface portion and the inner surface portion has a straight shape from top to bottom, The paper face piece for forming the cylindrical body is placed in a predetermined position as an insert in a mold for forming the framework, and resin is poured into the mold from the bottom side to obtain the composite container in which the framework and cylindrical body are joined. Effect of the Invention

[0011] According to the composite container of the present invention, the container portion is constructed using a resin framework and a paper tubular body, so that the amount of resin used can be significantly reduced compared to when the entire container portion is constructed from resin. Furthermore, the framework only needs to be made thick enough to compensate for the strength deficiency of the paper tubular body alone, so the amount of resin required for the framework can be reduced.

[0012] Here, a top frame is joined to the top edge of the paper tubular body. The top frame is easily subjected to force when contents are put into or taken out of the container that joins the top edge of the tubular body from both its inner and outer sides. However, in the composite container of the present invention, the top frame joins the top edge of the tubular body from both its inner and outer sides. Therefore, the joining state between the two can be well maintained even when such force is applied.

[0013] Furthermore, when the composite container is applied to a cup container for holding liquids such as beverages, moisture may adhere to the outer edge of the top surface. At the joint between the top frame and the cylindrical body, moisture may enter the top edge of the cylindrical body through a small gap at the joint interface between the two. There is a risk that the top edge of the cylindrical body will absorb moisture and become soft. However, in the composite container according to the present invention, the top frame joins the top edge of the cylindrical body from both its inner and outer surfaces, so that moisture is prevented from being absorbed from the end face of the top edge of the cylindrical body to the inside, and the strength of the cylindrical body can be maintained. Therefore, even when the contents are liquids, the joint state between the two can be well maintained.

[0014] Furthermore, for example, by using an insert molding method and setting the paper face piece for forming the cylindrical body in a predetermined position in a mold for manufacturing the resin frame body and filling it with resin, the top frame body can be joined to the top edge part of the cylindrical body, eliminating the need to manufacture and assemble the resin and paper parts separately, thereby improving manufacturing efficiency. As described above, according to the composite container and manufacturing method for a composite container of the present invention, by combining a resin framework with a paper tubular body, it is possible to reduce the amount of resin and improve manufacturing efficiency, and it is also possible to maintain a good bond between the resin framework and the top edge portion of the paper tubular body. [Brief description of the drawings]

[0015] [Figure 1]1A is a top view of the composite container according to an embodiment of the present invention, and FIG. 1B is a partial cross-sectional view of the composite container, where the cross-sectional portion represents the AA cross section of FIG. [Diagram 2] This is a side cross-sectional view showing the top portion of the composite container shown in Figure 1, where (a) is a side cross-sectional view at a position corresponding to the area surrounded by B in Figure 1(b), and (b) is a side cross-sectional view at a position where no side framework is present. [Diagram 3] 2A and 2B are diagrams showing paper face pieces that constitute the cylindrical body of the composite container shown in FIG. 1, where (a) shows the side paper face piece and (b) shows the bottom face piece. [Figure 4] 4 is a side sectional view as a comparative example for comparison with the side sectional structure of the top surface portion of the composite container of the present embodiment shown in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A composite container and a method for manufacturing a composite container according to an embodiment of the present invention will now be described with reference to the drawings.

[0017] 1. Composite containers A schematic configuration of a composite container 100 of this embodiment will be described with reference to Fig. 1. As shown in Fig. 1(b), the composite container 100 has a bottom surface 11 and a side surface 12, and a storage section 10 with an open top surface 13. The storage section 10 is cup-shaped, and the bottom surface 11 and the top surface 13 are each circular, with the top surface 13 having a larger diameter than the bottom surface 11. The bottom surface 11 and the top surface 13 are coaxial, and a line passing through the center of each surface is defined as a central axis O. However, Fig. 1(a) is a top view showing the composite container 100, and (b) is a partial cross-sectional view of the composite container 100.

[0018] The composite container 100 is a hybrid container in which resin members and paper members are integrated. Specifically, the storage section 10 has a framework (hereinafter referred to as framework 20) ​​made of resin members, and a paper tubular body 30 is joined to framework 20 to cover it. Hereinafter, with regard to framework 20, the part constituting the framework of the side portion of storage section 10 will be referred to as side framework 21, the part constituting the framework of the bottom portion will be referred to as bottom framework 22, and the part constituting the framework of the top portion will be referred to as top framework 23.

[0019] The side frame 21 has four support pillars 21a, one end of which is connected to the bottom frame 22 and the other end of which is connected to the top frame 23. These four support pillars 21a are disposed at equal intervals.

[0020] The bottom framework 22 includes a bottom frame 22a that constitutes the outer edge of the bottom surface 11 of the storage section 10, and a reinforcing portion 22b for supplementing the strength of the bottom surface 11. The bottom frame 22a is configured as an annular frame with an L-shaped cross section. The reinforcing portion 22b is shaped like a cross with the central axis O as its center. The reinforcing portion 22b is a plate-like member extending at 90 degree intervals from the center position of the bottom surface 11, and the ends of the plate-like member are connected to each support portion (21a) and are also connected to the bottom frame 22a. As shown in FIG. 2(a), each support portion 21a is joined to the inner surface of a side paper panel 31 (see FIG. 3(a)) that constitutes the cylindrical body 30.

[0021] The top frame 23 includes a top frame 23a that constitutes the outer edge of the top surface 13 of the storage unit 10, and a flange 23b that protrudes outward from the top frame 23a. The top frame 23a is configured in the shape of a ring frame having a predetermined length in the height direction. The flange 23b is connected to the top end of the top frame 23a. As shown in Figures 2(a) and (b), the top frame 23a has an inner surface portion 23c that is joined to the inner surface of the top edge 31d of the cylindrical body 30, and an outer surface portion 23d that is joined to the outer surface of the top edge 31d, and is joined so that the top edge 31d of the cylindrical body 30 is sandwiched between the inner surface portion 23c and the outer surface portion 23d.

[0022] In this embodiment, the cylindrical body 30 is formed by rolling up a fan-shaped paper side panel (paper panel) 31 shown in Fig. 2(a) and joining one end edge 31a and the other end edge 31b to form a cylindrical shape. The one end edge 31a and the other end edge 31b of this paper side panel 31 are joined at one of the four support parts 21a provided on the side frame 21. In this embodiment, the cylindrical body 30 is provided with a circular bottom paper panel 32 for covering the bottom frame 22 shown in Fig. 2(b). As shown in Fig. 1(b), the bottom end 31c of the side paper panel 31 (the bottom end of the cylindrical body 30) is joined to the bottom frame 22. The outer peripheral edge of the bottom paper panel 32 is joined to the bottom frame 22a of the bottom frame 22, and its inner surface is joined to the reinforcing part 22b.

[0023] In the composite container 100, the type of resin constituting the framework 20 is not particularly limited, but a wide variety of general-purpose resins such as polypropylene (homopolymer, block copolymer, random copolymer), polyethylene (high density polyethylene, low density polyethylene, etc.), and polyethylene terephthalate resins, which are used as packaging container materials, can be used. In particular, when employing the manufacturing method described below, olefin resins such as polypropylene and polyethylene are more preferable.

[0024] The paper face pieces (31, 32) constituting the cylindrical body 30 may be thin and flat formed by bonding together vegetable fibers or other fibers, and may be laminated or composite paper made by laminating synthetic paper or various plastics, or functional paper that has been given water resistance or oil resistance. The basis weight of the paper used can be appropriately designed. For example, the paper used has a basis weight of 100 g / m2. 2 More than 600g / m 2 The following can be used, preferably 250 g / m 2 More than 400g / m 2 The following ranges can be used. In particular, when employing the manufacturing method described below, it is more preferable to use a laminated paper having a surface layer of an olefin resin such as a polyethylene resin, thereby imparting functions such as water resistance and oil resistance.

[0025] 2. Manufacturing method of composite container Next, a method for manufacturing the composite container 100 will be described. When manufacturing the composite container 100, so-called insert molding can be used. A mold corresponding to the framework 20 and the paper side panel 31 and the paper bottom panel 32, which have been cut to a predetermined shape in advance, are prepared. Then, the paper side panel 31 and the paper bottom panel 32 are placed in the mold as inserts at predetermined positions, and resin is poured into the framework 20 from the bottom side. The mold is designed to pour resin into the center position of the reinforcing part 22b of the bottom framework 22.

[0026] As described above, the bottom frame 22, the side frame 21, and the top frame 23 are connected to one another. Therefore, the resin poured into the mold from the position corresponding to the center position of the reinforcing part 22b spreads outward in the radial direction and branches into four directions, and flows in this order through the bottom frame 22a to the side frame 21 and the top frame 23.

[0027] In this case, a polyolefin resin such as polypropylene is used as the filling resin material, and laminated paper with a polyolefin resin layer such as a polyethylene layer is used for at least the surface that will be joined to the framework 20 as the side paper faces 31 and the bottom paper faces 32, so that the framework 20 and each paper face (31, 32) are thermally fused together during the insert molding, and the framework 20 and each paper face (31, 32) can be joined without the use of adhesives or the like.

[0028] According to the composite container 100 described above, the storage section 10 is mainly constituted by the tubular body 30 with the paper side panel 31 in a cylindrical shape, while the strength of the tubular body 30 can be supplemented by the resin framework 20. Therefore, compared to a case where the entire storage section 10 is made of resin, the amount of resin used can be greatly reduced. Furthermore, the framework 20 only needs to be made thick enough to supplement the strength that is lacking with the paper tubular body 30 alone, so the amount of resin required for the framework 20 can be reduced.

[0029] Furthermore, in the composite container 100, the top frame 23 is joined to the top edge 31d of the paper tubular body 30. The outer edge of the top surface 13 is likely to receive force when putting contents into or taking them out of the storage section 10. In the composite container 100, the top edge 31d of the tubular body 30 is joined by being sandwiched from both the inner and outer sides by the inner surface part 23c and the outer surface part 23d of the top frame 23a, so that the tubular body 30 can be prevented from coming off the top frame 23 and the joining state between the two can be maintained in a good condition.

[0030] In addition, when the composite container 100 is applied to a cup container for holding liquid such as beverages, moisture may adhere to the outer edge of the top surface 13. The side cross-sectional views shown in Figs. 4(a) and (b) show the configuration of a comparative composite container for comparison with the composite container 100. The same components as those of the composite container 100 of this embodiment are given the same reference numerals. In the joint between the top frame 23 and the cylindrical body 30, for example, if the top frame 23a has only the inner surface 23c and does not have the outer surface 23d, as shown in Figs. 4(a) and (b), when water adheres to the top edge 31d of the cylindrical body 30, moisture may enter through a small gap at the joint interface between the top edge 31d of the cylindrical body 30 and the top frame 23a. For example, even if the side paper face 31 has a polyolefin resin layer on the surface and is water resistant, the side paper face 31 can be obtained by cutting such a laminated paper into a predetermined shape. Therefore, the end face of the top edge 31d is often not covered with such a water-resistant layer. If water seeps in from the cut end face, the paper side panel 31 will absorb the water and become swollen. However, in the composite container 100, the top edge 31d of the cylindrical body 30 is joined after its inner and outer surfaces are covered by the inner surface portion 23c and the outer surface portion 23d. Therefore, in the composite container 100, it is possible to prevent water from seeping into the inside of the paper side panel 31 from the top edge 31d of the cylindrical body 30, so that the cylindrical body 30 does not swollen, and the composite container 100 can maintain a good joining state between the two while maintaining the strength required for the composite container 100.

[0031] Furthermore, if the composite container 100 is manufactured by insert molding, each paper face piece (31, 32) is set as an insert in a predetermined position in a mold for manufacturing the frame 20, and resin is filled in to manufacture the composite container 100 in which the top frame 23 is joined to the top edge 31d of the cylindrical body 30 and the side frame 21 and the bottom frame 22 are joined to each paper face piece (31, 32). Furthermore, the cylindrical body 30 is a single side paper face piece 31 formed into a cylindrical shape, but as described above, one end edge 31a and the other end edge 31b of the side paper face piece 31 are joined at one of the four support parts 21a that constitute the side frame 21, so that the process of joining the ends of the cylindrical body 30 together is not necessary. Therefore, when manufacturing the composite container 100, the work of separately manufacturing and assembling the resin framework 20 and the paper tubular body 30 is not necessary, and manufacturing efficiency can be improved.

[0032] Therefore, according to the above embodiment of the composite container 100 and the manufacturing method for the composite container 100, by combining the resin framework 20 with the paper tubular body 30, it is possible to reduce the amount of resin and improve manufacturing efficiency, and it is possible to maintain a good joint between the resin framework 20 and the top edge 31d portion of the paper tubular body 30.

[0033] The composite container 100 and the manufacturing method of the composite container 100 described above are merely one aspect of the composite container and the manufacturing method of the composite container according to the present invention, and the present invention is not limited to the above embodiment, and can be appropriately modified within the scope of the present invention. For example, in the above embodiment, the framework 20 is joined to the inside of the cylindrical body 30, and the framework 20 is covered by the cylindrical body 30, but the composite container according to the present invention is not limited to this aspect. For example, the framework 20 may be joined to the outside of the cylindrical body 30 so that the framework 20 is not disposed inside the storage section 10, or a part of the framework 20 (for example, a part of the support part 21a or the bottom framework 22, etc.) is joined from the outside of the cylindrical body 30, and the rest is joined from the inside of the cylindrical body 30, and various other aspects can be applied. If the framework 20 is covered by the cylindrical body 30 as in the above embodiment, the framework 20 cannot be seen from the outside, and it becomes easy to apply various designs to the surface of the cylindrical body 30, for example. Therefore, it is preferable in terms of obtaining a highly designed appearance. On the other hand, if the framework 20 is joined from the outside of the cylindrical body 30, the framework 20 is not present inside the storage section 10, so that, for example, when cosmetics such as yogurt, pudding, or cream are stored in the storage section 10, it is possible to prevent the contents from adhering to the joint between the framework 20 and the cylindrical body 30 and making it difficult to remove the contents cleanly. It is possible to appropriately select whether the framework 20 is placed inside or outside the cylindrical body 30 depending on the contents.

[0034] In the above embodiment, the storage unit 10 is formed in a cup shape with the bottom surface 11 and the top surface 13 being circular, but the specific shape of the storage unit 10 is not particularly limited. For example, the storage unit 10 may be formed in a deep dish shape or a bottle shape, and the shapes of the bottom surface 11 and the top surface 13 are not limited to circles, but may be square, rectangular, polygonal, etc.

[0035] In the above embodiment, one side paper panel 31 is rolled and one end 31a is joined to the other end 31b, but the number of side paper panels 31 used to form the side 12 of the storage section 10 is not particularly limited, and two or more sheets may be used and the ends of each side paper panel 31 joined to obtain the tubular body 30. Also, one side paper panel 31 may have a cut portion, and the cut edges may be joined to each other using a part of the side framework 21 as in the above embodiment. In this way, storage sections 10 of various shapes can be formed.

[0036] 2(a) and (b), the inner surface portion 23c and the outer surface portion 23d provided on the top frame 23a have shapes that are approximately line-symmetrical with the lower end (position on the bottom surface 11 side) at approximately the same position on the inner and outer surfaces of the paper side panel 31, but the configuration of the top frame of the composite container according to the present invention is not limited to the embodiment shown in Fig. 2(a) and (b). For example, the shapes of the inner surface portion 23c and the outer surface portion 23d do not need to be approximately line-symmetrical with respect to the paper side panel 31, and the outer surface portion 23d may be located above (top surface 13 side) or below (bottom surface 11 side) the inner surface portion 23c with respect to the paper side panel 31 in the direction of the central axis O, and is not particularly limited.

[0037] Furthermore, in the above embodiment, the bottom surface 11 of the storage section 10 is formed using the bottom frame assembly 22 and the bottom paper panel 32, but the shape of the bottom frame assembly 22 is not particularly limited, and there is no need to provide the reinforcing portion 22b as long as the strength of the bottom surface 11 required for the composite container 100 can be maintained. Furthermore, the entire surface of the bottom surface 11 may be formed from a resin bottom plate material, and the configuration of the bottom surface 11 is not particularly limited.

[0038] In addition, while manufacturing the above-mentioned composite container 100 by insert molding results in good manufacturing efficiency, it is also possible to prepare the framework 20 and the paper faces 31, 32 separately and join the two together by adhering the paper face 31 to the framework 20 using an adhesive or by welding them by applying heat locally. [Explanation of symbols]

[0039] 10: Storage section 11: Bottom 12: Side 13: Top 20: Frame body 21: Side frame 21a: Support section 22: Bottom frame 22a:Bottom frame body 22b: Reinforcement part 23: Celestial skeleton body 23a: Top frame 23b: Flange part 23c:Inner surface 23d: External part 30: Cylindrical body 31:Paper face piece on the side 31a: One edge 31b: other edge 31c: Bottom edge 31d: Top edge 32: Paper bottom panel 100: Composite container O: Center axis line

Claims

1. The container has a bottom surface and a side surface, and an open top surface. The container is constructed using a resin framework and a paper tubular body. The framework comprises a top framework which constitutes the outer edge of the top surface and which joins the top edge of the cylindrical body from both the inner and outer sides, a bottom framework which constitutes the framework of the bottom surface, and a support part which is joined to the inner surface of the cylindrical paper face body which constitutes the side surface and which connects the bottom framework and the top framework, The support pillar is not provided on the outer surface of the paper face piece, and is joined only to the inner surface of the paper face piece with respect to the side surface, The top frame includes an annular top frame body joined to the top edge portion, and a flange portion protruding radially outward from the upper end of the top frame body, The lower surface of the flange portion is located above the top edge portion, The top frame body includes an inner surface portion joined to the inner surface side of the top edge portion and an outer surface portion joined to the outer surface side of the top edge portion, an upper end of the support portion is connected to the inner surface portion; The plate thickness of the outer surface portion decreases from the flange portion side toward the bottom surface side, a portion of the outer surface of the top frame body that connects a lower end of the outer surface portion and the lower surface of the flange portion is inclined so as to be positioned radially outward as it extends upward, the plate thickness of each of the outer surface portion and the inner surface portion decreases from the flange portion side toward the bottom surface side, and a lower end of the outer surface portion and a lower end of the inner surface portion are located at the same height; A composite container, wherein the portion of the top edge portion sandwiched between the outer surface portion and the inner surface portion has a straight shape from top to bottom.

2. The cylindrical body is formed into a cylindrical shape by joining end sides of one or more of the paper face pieces, The composite container according to claim 1 , wherein one end edge and the other end edge of the paper panel are joined to each other at the support portion.

3. 3. A composite container according to claim 1 or claim 2, wherein the cylindrical body is constructed using one or more of the paper panels having a polyolefin-based resin layer on the surface thereof, and the framework is constructed from a polyolefin-based resin.

4. A method for manufacturing a composite container comprising a container section having a bottom surface and side surfaces and an open top surface, the container section being constructed using a resin framework and a paper tubular body, the method comprising the steps of: The framework comprises a top framework which constitutes the outer edge of the top surface and which joins the top edge of the cylindrical body from both the inner and outer sides, a bottom framework which constitutes the framework of the bottom surface, and a support part which is joined to the inner surface of the cylindrical paper face body which constitutes the side surface and which connects the bottom framework and the top framework, The support pillar is not provided on the outer surface of the paper face piece, and is joined only to the inner surface of the paper face piece with respect to the side surface, The top frame includes an annular top frame body joined to the top edge portion, and a flange portion protruding radially outward from the upper end of the top frame body, The lower surface of the flange portion is located above the top edge portion, The top frame body includes an inner surface portion joined to the inner surface side of the top edge portion and an outer surface portion joined to the outer surface side of the top edge portion, an upper end of the support portion is connected to the inner surface portion; The plate thickness of the outer surface portion decreases from the flange portion side toward the bottom surface side, a portion of the outer surface of the top frame body that connects a lower end of the outer surface portion and the lower surface of the flange portion is inclined so as to be positioned radially outward as it extends upward, the plate thickness of each of the outer surface portion and the inner surface portion decreases from the flange portion side toward the bottom surface side, and a lower end of the outer surface portion and a lower end of the inner surface portion are located at the same height; The portion of the top edge portion sandwiched between the outer surface portion and the inner surface portion has a straight shape from top to bottom, A method for manufacturing a composite container, comprising: placing the paper face piece for constituting the cylindrical body in a predetermined position as an insert in a mold for forming the framework; and pouring resin into the mold from the bottom side to obtain a composite container in which the framework and the cylindrical body are joined together.

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