Composite container and its manufacturing method

Abstract

To provide a composite container and a manufacturing method thereof capable of preventing partial discoloration of a side wall and maintaining a good joining state between the side wall and a resin member by suppressing intrusion of moisture and oil from an end surface (cut surface) of the side wall.SOLUTION: In a composite container comprising a storage part 10 which has a bottom surface 11 and a side surface 12 and allows a top surface 13 to be opened, the storage part 10 has a paper-made side wall 30 formed in a predetermined shape and a resin-made frame 20 joined to the side wall 30. Inner surfaces 21c, 22c and 23c and outer surfaces 21d, 22d and 23d of the frame 20 are joined together in a state of sandwiching each end surface of the side wall 30 from both sides of the inside and the outside, thereby covering the end surface.SELECTED DRAWING: Figure 1

Description

[Technical Field]

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

[0002] In recent years, efforts have been made to reduce the amount of resin used in disposable containers in order to curb 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. Furthermore, composite containers that combine plastic containers with paper components have also been proposed. For example, the composite containers described in Patent Documents 1 and 2 below are made primarily of paper, with resin coating layers laminated on both the front and back sides, and the body of the container is formed from paper side walls (sheet planks) that are cut to a predetermined shape.These side walls are set in a mold as insert materials, and the framework parts other than the side walls (flanges, pillars, etc.) are made of resin members, thereby forming the container as a single unit. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 1-279039 [Patent Document 2] Japanese Patent Publication No. 53-83879 Summary of the Invention [Problem to be solved by the invention]

[0004] Among the means for solving the above problems, the first main means of the present invention is: The container has a bottom surface and a side surface, and an open top surface. The container is connected to a side wall body made of paper and formed in a predetermined shape. and a bottom frame that constitutes the bottom surface, a side frame that constitutes the side surface, and a top frame that constitutes the top surface. A composite container having a resin framework, The bottom frame body has a bottom inner surface portion and a bottom outer surface portion that evenly sandwich and cover the inner and outer surfaces of the bottom end faces of the side wall bodies from both sides, the side frame body has a support inner surface portion and a support outer surface portion that evenly sandwich and cover the inner and outer surfaces of the circumferential end faces of one or more of the side wall bodies from both sides, and the top frame body has a top inner surface portion and a top outer surface portion that evenly sandwich and cover the inner and outer surfaces of the top end faces of the side wall bodies from both sides, The framework (20) is provided with The bottom inner surface portion, the bottom outer surface portion, the support column inner surface portion, the support column outer surface portion, the top inner surface portion, and the top outer surface portion are Towards the tip gradually The wall member has a tapered shape and is joined to the side wall body.

[0005] The present invention aims to solve the problems of the conventional technology described above by creating a composite container and a manufacturing method thereof that suppresses the penetration of moisture and oil from the end surface (cut surface) of the side wall body, prevents partial discoloration of the side wall body, and maintains a good bond between the side wall body and the resin member. [Means for solving the problem]

[0006] Among the means for solving the above problems, the first main means of the present invention is: A composite container comprising a storage section having a bottom surface and side surfaces and an open top surface, the storage section having a paper side wall body formed in a predetermined shape and a resin framework body joined to the side wall body, The inner and outer surface portions of the framework are covered by joining the end faces of the side wall body so as to sandwich them from both the inside and outside.

[0007] In the first main aspect of the present invention, the end faces of the side wall body can be reliably covered. Composite container.

[0009] In the above-mentioned means, by constructing the framework as an integral unit, the number of parts can be reduced, thereby achieving a reduction in manufacturing costs.

[0011] The above means can cover not only the bottom and top end surfaces of the paper side wall bodies, but also the end faces of the side wall bodies that are arranged adjacent to each other in the circumferential direction.

[0012] Another means of the present invention is any of the above means, plus the addition that the side wall body is constructed using one or more paper face bodies having a polyolefin resin layer on the surface, and the framework body is constructed from polyolefin resin.

[0013] The above means can strengthen the bond between the side wall and the framework, and can achieve a composite container with a side wall that is resistant to moisture and oil.

[0014] The second main means of the present invention is Any of the above A method for manufacturing a composite container, comprising: The framework is comprised of a bottom framework having a bottom inner surface portion and a bottom outer surface portion that sandwich and cover the bottom end surfaces of the side wall bodies from both the inner and outer surfaces, a side framework having a support inner surface portion and a support outer surface portion that sandwich and cover the end surfaces of one or more side wall bodies from both the inner and outer surfaces, and a top framework having a top inner surface portion and a top outer surface portion that sandwich and cover the top end surfaces of the side wall bodies from both the inner and outer surfaces, an installation step of installing the side wall body made of a paper face body as an insert material at a predetermined position in a mold for forming the framework body; an injection step of joining the framework and the side wall bodies by pouring resin into the mold from the bottom surface side, The installation step includes a step of arranging the bottom end surface, the end surface of the one or more side wall bodies, and the top end surface so as to protrude into a flow path within the mold, In the injection process, the resin flowing through the flow path is diverted inward and outward by the bottom end face, the end face of the one or more side wall bodies, and the top end face.

[0015] In the second main means of the present invention, the resin flowing through the flow path is diverted to the inside and outside, thereby simultaneously forming the bottom inner surface and bottom outer surface of the bottom frame, simultaneously forming the column inner surface and column outer surface of the side frame, and simultaneously forming the top inner surface and top outer surface of the top frame. [Effects of the Invention]

[0016] The present invention makes it possible to prevent moisture and oil from penetrating into the interior of the paper side wall from the end surface (cut surface), thereby preventing partial discoloration of the side wall and further maintaining a good bond between the paper side wall and the resin framework. [Brief explanation of the drawings]

[0017] [Figure 1] 1A and 1B show a composite container as an embodiment of the present invention, in which FIG. 1A is a plan view of the composite container, and FIG. 1B is a half cross-sectional side view taken along line bb in FIG. 1A. [Figure 2] 1(a) is a side cross-sectional view at a position corresponding to the area surrounded by IIa in FIG. 1(b), and FIG. 1(b) is a side cross-sectional view at a position corresponding to the area surrounded by IIb in FIG. 1(b). [Figure 3] 1(a) is a side cross-sectional view at a position corresponding to the region surrounded by IIIa in FIG. 1(b), and FIG. 1(b) is a side cross-sectional view at a position corresponding to the region surrounded by IIIb in FIG. 1(b). [Figure 4] FIG. 4 is a partial perspective view showing a state cut along line IV-IV in FIG. 1(b). [Figure 5] FIG. 2 is a development view showing two paper panels that make up the side walls of the composite container. DETAILED DESCRIPTION OF THE INVENTION

[0018] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. 1. Composite containers First, with reference to FIG. 1, a schematic configuration of a composite container 100 according to the present embodiment will be described. As shown in Fig. 1(b), the composite container 100 has a bottom surface 11 and side surfaces 12, and includes a storage section 10 that is open to a top surface 13. The storage section 10 is cup-shaped, and the bottom surface 11 and top surface 13 are both circular, with the top surface 13 having a larger diameter than the bottom surface 11. The bottom surface 11 and top surface 13 are coaxial, and a line passing through the center of each is defined as a central axis O.

[0019] The composite container 100 is a hybrid container (also called a pillared container) that integrates resin and paper components. Specifically, the storage section 10 has a framework (hereinafter referred to as framework 20) ​​made of resin components, and two semi-cylindrical paper side walls 30 are joined to framework 20. Hereinafter, with regard to framework 20, the part that forms the framework of the side surface of storage section 10 will be referred to as side framework 21, the part that forms the framework of the bottom surface 11 will be referred to as bottom framework 22, and the part that forms the framework of the top surface will be referred to as top framework 23.

[0020] The bottom framework 22 includes a bottom frame 22a that forms the outer edge of the bottom surface 11 of the storage section 10, and a bottom wall 22b that forms the bottom surface 11. The bottom frame 22a is configured as an annular frame with an L-shaped cross section. The bottom wall 22b is disk-shaped with the central axis O as its center, and forms the bottom surface 11 that is integrally connected to the inner peripheral surface of the bottom wall 22b. As shown in Figures 2(a) and (b), the bottom frame 22a has a bottom inner surface portion 22c joined to the inner surface side of the bottom end surface 31c portion of the side wall body 30 and a bottom outer surface portion 22d joined to the outer surface side, and covers the bottom end surface 31c portion of the side wall body 30 by being joined so as to sandwich it from both the inner and outer surfaces.

[0021] The top frame 23 includes a top frame 23a that forms the outer edge of the top surface 13 of the storage unit 10, and a flange 23b that protrudes radially outward from the top frame 23a. The top frame 23a is configured as a ring-shaped frame with a predetermined length in the height direction. The flange 23b is connected to the top end of the top frame 23a. As shown in FIGS. 3(a) and 3(b), the top frame 23a has a top inner surface 23c that is joined to the inner side of the top end surface 31d of the side wall 30, and a top outer surface 23d that is joined to the outer side of the top end surface 31d. The top inner surface 23c and the top outer surface 23d are joined together so as to sandwich and cover the top end surface 31d of the side wall 30 from both the inner and outer sides.

[0022] The side frame body 21 has two support columns 21a extending in the height direction, with its lower end connected to the bottom frame body 22 and its upper end connected to the top frame body 23. These two support columns 21a are arranged in positions that are symmetrical with respect to the central axis O. As shown in FIG. 4, each support column 21a has a support inner surface portion 21c that joins one end face 31a constituting one side wall body 30A of the two side wall bodies 30 to the other end face 31b of the other side wall body 30B from the inner surface side, and a support outer surface portion 21d that joins them from the outer surface side, and the support inner surface portion 21c and the support outer surface portion 21d are joined together so as to sandwich both end faces (one end face 31a and the other end face 31b) of the two side wall bodies 30 from both the inner and outer surfaces, thereby covering them.

[0023] In this embodiment, the side wall bodies 30A and 30B constituting the two side wall bodies 30 are formed by cutting and bending two fan-shaped paper panels 31 shown in Fig. 5, and are formed into a cylindrical shape by joining one end face 31a of one side wall body 30A and the other end face 31b of the other side wall body 30B in a state where they are arranged opposite each other with a predetermined gap between them, as shown in Fig. 4. The end faces of these two side wall bodies 30 are joined between two support parts 21a that are arranged symmetrically about the axis and constitute the side framework body 21.

[0024] In the composite container 100 of the present invention, the type of resin constituting the framework 20 is not particularly limited, but a wide range of general-purpose resins used as packaging container materials can be used, such as polypropylene (homopolymer, block copolymer, random copolymer), polyethylene (high-density polyethylene, low-density polyethylene, etc.), polyethylene terephthalate resin, etc. In particular, when employing the manufacturing method described below, olefin-based resins such as polypropylene and polyethylene are more preferable.

[0025] The paper face 31 that constitutes the side wall 30 may be formed thin and flat by agglutinating plant fibers or other fibers, and may be a laminated or composite paper made by laminating so-called synthetic paper or various plastics, or may be functional paper that has been given water resistance or oil resistance. The basis weight of the paper used can be designed as appropriate. For example, the paper used has a basis weight of 100 g / m2 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 laminated paper that has an olefin resin layer such as polyethylene resin laminated on the surface to impart functions such as water resistance and oil resistance.

[0026] 2. Manufacturing method of composite container Next, a method for manufacturing the composite container 100 will be described with reference to Figures 2 to 4. Note that the mold is omitted from Figures 2 to 4. When manufacturing the composite container 100, so-called insert molding can be employed. A mold corresponding to the framework 20 and two side wall bodies 30 pre-cut into a predetermined shape (fan shape) are prepared. Then, the two side wall bodies 30 are placed in predetermined positions in the mold as inserts (placement process). At this time, the end faces of the side wall bodies 30, i.e., the bottom end face 31c portion, the top end face 31d portion, the one end face 31a, and the other end face 31b of the side wall body 30, are positioned so as not to contact the inner circumferential surface of the mold and to protrude into the flow path through which the resin flows, and the resin is poured into the bottom side of the framework 20 (injection process). The mold is configured so that the resin is poured through a gate provided at the center of the underside of the bottom wall portion 22b of the bottom framework 22.

[0027] As described above, the bottom frame 22, the side frame 21, and the top frame 23 are interconnected. Therefore, the resin R poured into the mold from the gate provided at a position corresponding to the center position of the bottom wall 22b flows radially outward along the bottom wall 22b, and then flows through the bottom frame 22a of the bottom frame 22 provided on the outer periphery, into the side frame 21, and then into the top frame 23.

[0028] In the above-mentioned injection process, in the bottom frame body 22a of the bottom framework body 22, as shown in Figures 2(a) and (b), the resin R flowing through the flow path within the mold is divided into two directions at the bottom end face 31c, one flowing along the inner side and the other flowing along the outer side, so that a bottom inner surface portion 22c and a bottom outer surface portion 22d are simultaneously formed, which join the bottom end face 31c portion of the side wall body 30 while sandwiching it from both the inner and outer sides.

[0029] The resin R then flows from the bottom frame 22a toward the top frame 23 through the flow paths that form the support sections 21a (support inner surface sections 21c and support outer surface sections 21d) that make up the side frames 21. At this time, as shown in Fig. 4, the resin R is divided into two directions at the bottom end surface 31c, with one flow (the inner flow indicated by the dashed line) flowing inside the support section 21a and the other flow (the outer flow indicated by the solid line) flowing outside the support section 21a. Therefore, the resin R flowing inside and outside the support section 21a simultaneously forms the support inner surface section 21c and the support outer surface section 21d that join one end surface 31a of one side wall body 30A and the other end surface 31b of the other side wall body 30B in a state where they are sandwiched together from both the inner and outer surfaces.

[0030] Furthermore, at the top end surface 31d of the side wall 30, the resin R that flows while forming the support inner surface 21c and the support outer surface 21d meets once near the upper end of the support portion 21a after passing upward through the top end surface 31d, and then splits into two flows in the circumferential direction to form the top frame 23a and the flange portion 23b. The resin R that forms the top frame 23a is split into two flows—one that flows circumferentially on the inside and one that flows circumferentially on the outside—by one end surface 31a of one side wall 30A and the other end surface 31b of the other side wall 30B that protrude into the flow path within the mold, and these two flows of resin R are joined together so as to sandwich the top end surface 31d of the side wall 30 (side wall 30A and side wall 30B) from both the inside and outside, simultaneously forming the top inner surface 23c and the top outer surface 23d.

[0031] In this case, a polyolefin resin such as polypropylene is used as the filling resin material, and a laminated paper having a polyolefin resin layer such as a polyethylene layer laminated on at least the surface that is joined to the framework 20 is used as the paper face 31 that constitutes the side wall 30, so that the framework 20 and the paper face 31 are thermally fused together during the insert molding, and the framework 20 and the paper face 31 can be joined without using adhesives or the like.

[0032] According to the composite container 100 described above, the bottom end surface 31c portion of the side wall body 30 is joined so as to be sandwiched between the bottom inner surface portion 22c and the bottom outer surface portion 22d, the top end surface 31d portion of the side wall body 30 is joined so as to be sandwiched between the top inner surface portion 23c and the top outer surface portion 23d, and further, both end surfaces of the two side wall bodies 30 (one end surface 31a and the other end surface 31b) are joined so as to be sandwiched together by the support inner surface portion 21c and the support outer surface portion 21d from both the inner and outer surfaces. That is, each end face portion of the side wall body 30, that is, the bottom end face 31c portion, the top end face 31d portion, and both end face portions, i.e., one end face 31a and the other end face 31b, of the side wall body 30, are covered by being joined so as to sandwich them from both the inner and outer sides with the respective resins that form the bottom inner surface portion 22c and the bottom outer surface portion 22d, the top inner surface portion 23c and the top outer surface portion 23d, and further the support inner surface portion 21c and the support outer surface portion 21d.

[0033] Therefore, even if the paper material layered inside the paper panel 31 constituting the two side walls 30 (side walls 30A and 30B) is exposed at each end face (cut surface) after cutting, the resins R sandwiching the paper panel 31 cover it and isolate it from the outside. Therefore, even if moisture or oil contained in a liquid such as a beverage (e.g., coffee) filled in the composite container 100 adheres to the joint boundary between each end face of the side wall 30 and each resin, the resins constituting the bottom inner surface 22c and bottom outer surface 22d, the top inner surface 23c and top outer surface 23d, and even the support inner surface 21c and support outer surface 21d cover each end face, preventing the moisture or oil from penetrating. As a result, the composite container 100 of the present invention can prevent the side wall 30 from partially discoloring, becoming swollen, or otherwise deteriorating in physical properties.

[0034] Furthermore, in the composite container 100, the storage section 10 is mainly formed of the semi-cylindrical paper side wall 30, and the framework 20 is made of resin, which makes it possible to supplement the strength of the side wall 30. Therefore, compared to when the entire storage section 10 is made of resin, the amount of resin used can be significantly reduced. Furthermore, the framework 20 only needs to be made thick enough to compensate for the strength deficiency of the paper side wall 30 alone, so the amount of resin required for the framework 20 can be reduced.

[0035] Furthermore, in the composite container 100, the top frame 23 is joined to the top end surface 31d of the side wall 30. The outer edge of the top surface 13 is prone to receiving force when, for example, putting contents into or removing them from the storage section 10. In the composite container 100, the top end surface 31d of the side wall 30 is joined by the top inner surface 23c and the top outer surface 23d of the top frame 23a so as to sandwich it from both the inner and outer surfaces, which prevents the side wall 30 from coming off the top frame 23 and maintains a good joining state between them.

[0036] Furthermore, if the composite container 100 is manufactured by the insert molding method as described above, the paper face body 31 that constitutes the side wall body 30 can be set in a predetermined position as an insert material in a mold for manufacturing the frame body 20, and resin can be filled in to manufacture a composite container 100 in which the top frame body 23 is joined to the top end face 31d of the side wall body 30, the bottom frame body 22 is joined to the bottom end face 31c, and the side frame bodies 21 are joined between one end face 31a and the other end face 31b.

[0037] Moreover, in the manufacturing method of the composite container 100, the bottom inner surface portion 22c and the bottom outer surface portion 22d, the support inner surface portion 21c and the support outer surface portion 21d, and the top inner surface portion 23c and the top outer surface portion 23d, which join the end faces of the side wall body 30 from both the inner and outer surfaces, can be simultaneously formed, eliminating the need for separate joining operations and improving manufacturing efficiency. It is also possible to reduce the difference between the inside and outside of the joining boundary portion between each end face of the side wall body 30 and the resin (the difference in the degree of joining at the joining boundary portion on the inner side and the joining boundary portion on the outer side), which results in more effective prevention of moisture and oil from penetrating into the side wall body 30.

[0038] Therefore, according to the composite container 100 and the manufacturing method for the composite container 100 of the above embodiment, by combining a resin skeleton body 20 and a paper side wall body 30, it is possible to reduce the amount of resin and improve manufacturing efficiency, and it is possible to maintain a good joint state at the bottom end face 31c portion, the top end face 31d portion, and the one end face 31a and the other end face 31b portion of the resin skeleton body 20 and the paper side wall body 30.

[0039] The composite container 100 and the method for manufacturing the composite container 100 described above are merely one aspect of the composite container and the method for manufacturing the composite container according to the present invention, and the present invention is not limited to the above embodiment, but can be modified as appropriate within the scope that does not deviate from the spirit of the present invention.

[0040] For example, in the above embodiment, the side frame 21 is configured with two support pillars 21a arranged symmetrically about an axis, but it may be configured with one support pillar 21a or three or more. Also, while the side wall 30 is configured with two sheets, the side wall 30 may be configured by rolling one paper panel 31 and joining one end face 31a to the other end face 31b with a support pillar 21a, or it may be configured by joining the end faces of three or more side wall bodies 30 with a plurality of support pillars 21a.

[0041] In the above embodiment, one end face 31a and the other end face 31b of each of the two side wall bodies 30 are connected to each other by two support columns 21a, but it is sufficient that they are connected by at least one support column 21a. In this case, the lack of additional support columns 21a results in a lower strength, but the strength problem can be solved by connecting the bottom frame body 22 and the top frame body 23 with simple columns that do not have any joining function. The simple columns may be provided on the inside or outside of the side wall bodies 30.

[0042] In the above embodiment, the storage section 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 section 10 is not particularly limited. For example, the storage section 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.

[0043] Furthermore, in the above embodiment, the entire bottom surface 11 of the bottom frame 22 is formed from the resin bottom wall portion 22b, but the shape of the bottom frame 22 is not particularly limited, and the bottom surface 11 may be formed using the bottom frame 22 and a circular paper face piece. In this case, it is preferable that the resin that forms the bottom frame 22 be joined so as to sandwich the peripheral portion of the circular paper face piece that forms the bottom surface 11 from both the upper and lower surfaces. [Industrial Applicability]

[0044] The present invention can expand the range of applications in the field of composite containers that are composed of a paper side wall and a resin framework. [Explanation of symbols]

[0045] 10: Storage section 11: Bottom 12: Side 13: Top 20: Skeleton body 21: Side frame 21a: Support column 21c: Inner face of the strut (inner face) 21d: Outer part of the support (outer part) 22: Base bone assembly 22a: Bottom brace 22b: Bottom wall portion 22c: Inner face (bottom face) 22d: Bottom outer surface (outer surface) 23: Tian Gu Group 23a: Tianli body 23b :Florinobe 23c: Inner face (or inner face) 23d: Outer part of the sky (outer part) 30: Side wall body 31: paper face body 31a:One end face 31b: His side 31c: Bottom surface 31d: Tian Duan Mian 100: Composite container O: Central axis R: Resin

Claims

1. A composite container comprising a storage section (10) having a bottom surface (11) and side surfaces (12) and an open top surface (13), the storage section (10) having a paper side wall body (30) formed in a predetermined shape, a bottom frame body (22) joined to the side wall body (30) and constituting the bottom surface (11), a side frame body (21) constituting the side surfaces (12), and a top frame body (23) constituting the top surface (13), and a resin frame body (20) integrally formed therewith, The bottom frame (22) has a bottom inner surface portion (22c) and a bottom outer surface portion (22d) that evenly sandwich and cover the inner and outer surfaces of the bottom end surface (31c) of the side wall body (30) from both sides, the side frame (21) has a support column inner surface portion (21c) and a support column outer surface portion (21d) that evenly sandwich and cover the inner and outer surfaces of the circumferential end surfaces (31a, 31b) of one or more of the side wall bodies (30) from both sides, and the top frame (23) has a top inner surface portion (23c) and a top outer surface portion (23d) that evenly sandwich and cover the inner and outer surfaces of the top end surface (31d) of the side wall body (30) from both sides, The composite container is characterized in that the bottom inner surface portion (22c), the bottom outer surface portion (22d), the support pillar inner surface portion (21c), the support pillar outer surface portion (21d), the top inner surface portion (23c), and the top outer surface portion (23d) provided on the framework body (20) have shapes that gradually taper toward their tips and are joined to the side wall body (30).

2. 2. A composite container according to claim 1, wherein the side wall (30) is constructed using one or more paper face pieces (31) having a polyolefin resin layer on the surface, and the framework (20) is constructed from polyolefin resin.

3. A method for manufacturing the composite container according to claim 1 or 2, The framework (20) is configured to include a bottom framework (22) having a bottom inner surface portion (22c) and a bottom outer surface portion (22d) that sandwich and cover the bottom end surface (31c) of the side wall body (30) from both the inner and outer surfaces, a side framework (21) having a support inner surface portion (21c) and a support outer surface portion (21d) that sandwich and cover the end surfaces (31a, 31b) of one or more side wall bodies (30) from both the inner and outer surfaces, and a top framework (23) having a top inner surface portion (23c) and a top outer surface portion (23d) that sandwich and cover the top end surface (31d) of the side wall body (30) from both the inner and outer surfaces, an installation step of installing the side wall body (30) made of a paper face body (31) at a predetermined position as an insert material in a mold for molding the framework body (20); an injection step of joining the framework (20) and the side wall (30) by pouring resin into the mold from the bottom surface (11) side; The installation step includes a step of arranging the bottom end surface (31c), the end surfaces (31a, 31b) of the one or more side wall bodies (30), and the top end surface (31d) so that they protrude into a flow path within the mold, A method for manufacturing a composite container, characterized in that in the injection process, the resin (R) flowing in the flow path is diverted to the inside and outside by the bottom end surface (31c), the end surfaces (31a, 31b) of the one or more side wall bodies (30), and the top end surface (31d).

4. 4. A method for manufacturing a composite container according to claim 3, wherein the resin (R) flows through the bottom frame (22), the side frame (21) and the top frame (23) in this order.

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