Composite containers

Abstract

To provide a composite container and a manufacturing method for the same that can significantly reduce the amount of resin and improve manufacturing efficiency by combining a resin framework and a film body while maintaining functions required for the film body.SOLUTION: A composite container 100 has a housing section 10 that has a bottom surface 11 and a side surface 12 and is configured by using a resin framework 20 and a film body 30. The film body 30 is made of one or more film bodies 31 in a cylindrical shape. The framework 20 has a joint part 21a that is interposed between one end edge 31a and the other end edge 31b of the film body 31 and covers the entire end surface of the film body 31 at the one end edge 31a and the other end edge 31b.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a composite container. In a container Regarding. [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. For example, Patent Document 1 discloses a resin container having a body composed of a thin-walled portion having a thickness of 0.01 mm to 0.09 mm and a thick-walled portion having a protrusion protruding radially outward. However, when the body is composed of such a thin-walled portion, the body is easily deformed and cannot be gripped. Therefore, in this resin container, a flange having a thickness of 0.5 mm to 2.0 mm is provided on the thick-walled portion via a connecting portion, and the body of the resin container is inserted into a cylindrical paper sleeve, and the sleeve is supported by the protrusion, thereby maintaining the strength of the resin container. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-116122 Summary of the Invention [Problem to be solved by the invention]

[0004] According to the resin container disclosed in Patent Document 1, although the amount of resin in the body is reduced, a thick portion, a sleeve, etc. are required, and a further reduction in the amount of resin is required. Furthermore, the container requires a paper sleeve to maintain the strength of the body, but the paper sleeve and the resin container must be manufactured separately and then combined, making the manufacturing process complicated.

[0005] Therefore, an object of the present invention is to provide a composite container that can further reduce the amount of resin and improve manufacturing efficiency, and can maintain the functionality required for the container portion. vessel The purpose is to provide. [Means for solving the problem]

[0006] In order to solve the above problems, the composite container according to the present invention has a bottom surface and a side surface, and includes a storage section formed using a resin framework and a film body whose edge portions are joined to the framework, The framework has a joint portion that is interposed between one end portion and the other end portion of the film body and covers the entire end surfaces of the one end portion and the other end portion. At the joint, the edge portion is folded to protrude from the outer surface of the film body and is embedded in the framework body. , characterized by:

[0007] In the above-mentioned composite container, it is preferable that the film body is a single-layer film or a multi-layer film, and includes at least one layer of a polyethylene resin layer, a polypropylene resin layer, a polyethylene terephthalate resin layer, a polyamide resin layer, an ethylene vinyl alcohol resin layer, and an aluminum layer.

[0009] In the above composite container, it is preferable that the framework comprises a bottom framework that forms the outer edge of the bottom surface, a top framework that forms the outer edge of the top surface of the storage section, and a side framework that includes the joint and is connected to the bottom framework and the top framework, the side surface of the storage section is formed by the side framework and a side film body that forms a cylindrical shape by joining one end edge portion and the other end edge portion to the joint portion, the bottom surface of the storage section is formed by the bottom framework and a bottom film body whose outer edge portion is joined to the bottom framework, the bottom edge portion of the cylindrical side film body is joined to the bottom framework and the top edge portion is joined to the top framework, and the end faces of the bottom edge portion and the top edge portion are entirely covered by the bottom framework and the top framework, respectively.

[0010] In this specification, the following technique is disclosed as an example of a method for manufacturing a composite container.A method for manufacturing the above-mentioned composite container is characterized in that it uses a mold having one mold member and the other mold member that are divided via a dividing surface, and by combining the one mold member and the other mold member, a resin filling section having a shape corresponding to the skeleton body is formed, the film body is placed between the one mold member and the other mold member so that an end edge portion of the film body is inserted into a joint forming area in the resin filling section that has a shape corresponding to the joint, and is clamped between the two mold members, and resin is filled into the resin filling section, thereby joining the one end edge portion and the other end edge portion of the film body at the joint, and the composite container in which the skeleton body and the film body are integrated is obtained.

[0011] the above In the method for manufacturing a composite container, it is preferable that a convex portion protruding from the dividing surface of one of the mold members toward the other mold member is provided within the joint formation area, and resin is filled into the resin filling portion while the edge portion of the film body is pushed up toward the other mold member by the convex portion.

[0012] the above In the method for manufacturing a composite container, at the position where the edge portion is located within the joint formation area, a recess is provided near the convex portion on the dividing surface of one of the mold members, and the convex portion and the recess are arranged in that order from the end face side of the edge portion, and when the resin is filled into the resin filling portion, it is preferable that the edge portion is bent by the resin filling pressure and the recess and the convex portion. [Effects of the Invention]

[0013] According to the composite container of the present invention, the storage section is constructed using a resin framework and a film body, so that the majority of the storage section is constructed from the film body, while the framework can compensate for the strength that would be lacking if the film body alone were used. Furthermore, since the framework only needs to contain an amount of resin sufficient to compensate for the strength, the amount of resin required to construct the composite container can be reduced.

[0014] Furthermore, in the composite container according to the present invention, a joint portion of the framework is interposed between one end edge portion and the other end edge portion of the film body, and the joint portion covers and joins the entire end faces of each end edge portion. For example, if the film body is a multilayer film containing a highly hydrophilic layer, if the end face of the film body is a cut surface, the highly hydrophilic layer may be exposed at the end face of the film body. In this composite container, the resin joint portion covers the entire end face of each end edge portion while joining the one end edge portion to the other end edge portion, thereby preventing moisture and the like from entering through the end face of the film body at the joint portion and suppressing problems such as the film body becoming soft and losing its rigidity, or in the case of a multilayer film, the film peeling from the end face side, or a decrease in the bonding strength between the end edges.

[0015] moreover, the above This method of manufacturing a composite container can be applied to insert molding. That is, by placing a film body in a predetermined position in a mold and filling the resin filling portion of the mold with resin, the edge of the film body is inserted into the joint formation region, and at the same time as forming the framework, one edge of the film body is joined to the other edge of the film body by the joint, thereby obtaining an integrated composite container. This extremely simplifies the manufacturing process and improves manufacturing efficiency.

[0016] As described above, the composite container and Disclosed herein According to the manufacturing method for a composite container, by combining a resin framework and a film body, it is possible to reduce the amount of resin used and improve manufacturing efficiency, while maintaining the functionality required for the storage section. [Brief explanation of the drawings]

[0017] [Figure 1] 1A and 1B are diagrams for explaining a composite container according to an embodiment of the present invention, in which (a) is a front view (partial cross-sectional view) of the composite container, and (b) is a bottom view of the composite container. [Figure 2] 2A and 2B are diagrams showing the composite container shown in FIG. 1, in which (a) is a top view and (b) is a side view (partial cross-sectional view). [Figure 3]2A and 2B are diagrams showing the film bodies that constitute the film body of the composite container shown in FIG. 1, where (a) shows the side film body that constitutes the side of the storage section, and (b) shows the bottom film body that constitutes the bottom of the storage section. [Figure 4] Regarding the composite container shown in Figure 1, (a) is a cross-sectional view taken along the line AA in Figure 1(a), (b) is a schematic diagram showing the cross-sectional side structure of the mold used to mold the relevant part, and (c) is a schematic diagram for explaining the molding method. [Figure 5] Regarding a comparative example for comparison with the composite container shown in Figure 1, (a) is a figure corresponding to Figure 4(a) in the comparative example, (b) is a schematic diagram showing the side cross-sectional structure of the mold used to mold the relevant part, and (c) is a schematic diagram for explaining the molding method. [Figure 6] 4A and 4B are diagrams for explaining a modified example of a composite container according to an embodiment of the present invention, in which (a) is a diagram corresponding to FIG. 4A in the modified example, (b) is a schematic diagram showing the cross-sectional side structure of a mold used to mold the relevant part, and (c) is a schematic diagram for explaining the molding method. [Figure 7] 4A and 4B are diagrams for explaining yet another modified example of a composite container according to an embodiment of the present invention, in which (a) is a diagram corresponding to FIG. 4A in this modified example, and (b) is a schematic diagram showing the cross-sectional side structure of a mold used to mold this part. DETAILED DESCRIPTION OF THE INVENTION

[0018] A composite container and a method for manufacturing a composite container according to an embodiment of the present invention will be described below with reference to the drawings.

[0019] 1. Composite containers First, a schematic configuration of a composite container 100 of this embodiment will be described with reference to Figures 1 to 3. Figure 1(a) is a front view (partial cross-sectional view) of the composite container 100, Figure 1(b) is a bottom view, Figure 2(a) is a top view, and Figure 2(b) is a side view (partial cross-sectional view). Note that the hatched portion in Figure 2(a) indicates an annular protruding rib 23f described later, and does not indicate a cross section.

[0020] As shown in Fig. 1(a), the composite container 100 has a bottom surface 11 and side surfaces 12, and is provided with a storage section 10 with an open top surface 13. In the composite container 100, the storage section 10 is composed of a resin framework 20 and a film body 30. As shown in Figs. 1(b) and 2(a), the storage section 10 is configured in a cup shape, and the bottom surface 11 and top surface 13 are each coaxially circular, with the top surface 13 having a larger diameter than the bottom surface 11.

[0021] As shown in FIG. 3, the film body 30 includes a side film body 31 and a bottom film body 32, each of which is formed into a predetermined shape. These films are joined to the framework 20 to form the bottomed, cylindrical storage section 10. Hereinafter, a line passing through the centers of the bottom surface 11 and the top surface 13 will be referred to as the central axis O, a direction along the central axis O will be referred to as the axial direction, a direction perpendicular to the central axis O will be referred to as the radial direction, and a direction circumferentially around the central axis O will be referred to as the circumferential direction. When the composite container 100 is placed in the state shown in FIG. 1, the bottom surface 11 side will be referred to as the "lower" side and the top surface 13 side will be referred to as the "upper" side in the axial direction. Note that FIGS. 1(a) and 2(a) each show a cross-sectional view to the right of the central axis O. The configurations of the framework 20 and the film body 30 will be described below.

[0022] As shown in Figures 1(a), (b) and 2(a), (b), the framework 20 comprises a side framework 21 that forms the framework of the side portion of the storage section 10, a bottom framework 22 that forms the framework of the bottom portion, and a top framework 23 that forms the framework of the top portion.

[0023] As shown in Figures 1(a) and 1(b), the side frame body 21 is composed of two support columns 21a, 21b, one end of which is connected to the bottom frame body 22 and the other end of which is connected to the top frame body 23. The two support columns 21a, 21b are arranged opposite each other across the central axis O. The connecting support column 21a and the reinforcing support column 21b protrude radially outward from the outer surface of the film body 30, i.e., the outer surface of the side film body 31, and are provided as convex ribs that extend axially from the bottom frame body 22 to the top frame body 23.

[0024] Of the two support columns 21a and 21b, the support column 21a corresponds to the joint portion referred to in the present invention. The other support column 21b functions as a reinforcing portion for supplementing the strength (rigidity) of the storage section 10. Hereinafter, the support column 21a will be referred to as the joint support column 21a, and the other support column 21b will be referred to as the reinforcing support column 21b. The joint support column 21a joins one end edge portion 31a and the other end edge portion 31b of the side surface film body 31 that constitutes the film body 30. The reinforcing support column 21b is joined (adhered) to the outer surface of the film body 30 (side surface film body 31). However, in the example shown in FIGS. 1(a) and 1(b), the reinforcing support column 21b is an optional configuration, and if the reinforcing support column 21b is not necessary due to the strength required of the storage section 10, the reinforcing support column 21b may be omitted. In this case, the amount of resin can be further reduced. Furthermore, the reinforcing support portion 21b may be replaced with the joining support portion 21a, and the storage section 10 may be constructed by joining two side surface film bodies 31. These can be changed as desired depending on the size of the storage section 10, and three or more side surface film bodies 31 may be joined, or the number of reinforcing support portions 21b may be increased.

[0025] The bottom frame 22 forms the outer edge of the bottom surface 11 of the storage section 10. As shown in Figures 1(a) and (b), the bottom frame 22 comprises a bottom annular frame 22a arranged on the bottom surface 11 side and a side annular frame 22b arranged on the side surface 12 side. The bottom annular frame 22a is configured as a flat ring with a thin axial thickness. The side annular frame 22b is thin in the radial direction and has a ring-shaped frame shape with a predetermined length in the axial direction. The bottom frame 22 has an approximately L-shaped cross section as the outer edge of the bottom annular frame 22a and the lower end of the side annular frame 22b are connected by a bottom bone joint 22c (see Figure 1(a)).

[0026] Furthermore, the bottom frame 22 is connected to the connecting struts 21a and reinforcing struts 21b of the side frame 21 by connecting portions 22d. As shown in Figures 1(a) and 1(b), the connecting portions 22d are provided from the bottom surface 11 side of the storage section 10 to the side surface 12 side of the bottom bone connecting portion 22c, and are integrated with the connecting struts 21a on the side surface 12 of the storage section 10. Furthermore, as shown in Figures 1 and 2, the outer edge of the bottom film body 32 is joined to the inner edge portion of the bottom annular frame 22a from the inner surface side of the bottom annular frame 22a, and the bottom edge portions 31c of the side film body 31 are joined to the upper end portions of the side annular frame 22b from the outer surface side of the side annular frame 22b.

[0027] The top frame 23 forms the outer edge of the top surface 13 of the storage section 10. As shown in Figures 1(a) and 2(b), the top frame 23 comprises an inner frame 23a joined to the top edge 31d of the side film body 31, a flange 23b protruding outward from the upper end of the inner frame 23a, and an outer frame 23c suspended from the outer edge of the flange 23b. The inner frame 23a and outer frame 23c each have a predetermined length in the axial direction and are configured as ring frames with a thin radial thickness. In other words, the top frame 23 has a U-shaped cross section that is open downwards, due to the inner frame 23a, flange 23b, and outer frame 23c. In the composite container 100 of this embodiment, the top frame body 23 is configured to have a U-shaped cross section, which allows the thickness of the inner frame body 23a, flange portion 23b, and outer frame body 23c to be made thin, making it easier to maintain the required strength even when the amount of resin is reduced.

[0028] In this embodiment, as shown in Figures 1(a) and 1(b), four inner peripheral ribs 23d are provided at equal intervals along the inner peripheral surface at the lower end of the inner peripheral surface of the outer frame body 23c. The inner peripheral ribs 23d protrude radially inward from the inner peripheral surface of the outer frame body 23c and have a predetermined width in the circumferential direction. By providing the inner peripheral ribs 23d on the inner peripheral surface of the outer frame body 23c, the strength of the top frame body 23 can be increased. Furthermore, when the composite container 100 is used as a refill container, the inner peripheral ribs 23d can be used to fit into an undercut provided at the joint portion.

[0029] An outer peripheral rib 23e is provided around the entire circumference of the lower end of the outer peripheral surface of the outer frame 23c so as to protrude radially outward. By providing these inner peripheral rib 23d and outer peripheral rib 23e, the strength required for the top surface 13 of the storage section 10 can be more favorably maintained even when the thicknesses of the inner frame 23a, flange portion 23b, and outer frame 23c are reduced.

[0030] 1(a), 2(a), and 2(b), an annular convex rib 23f that protrudes upward in the axial direction is provided on the top surface 13 of the flange portion 23b. The annular convex rib 23f is used as a contact ring for the packing seal.

[0031] Next, the joining state between the framework 20 and the film body 30 (film bodies (31, 32)) will be described. In this embodiment, the film body 30 is formed into a cylindrical shape by rolling up a side film body (film body) 31 cut into a predetermined shape such as a fan shape as shown in FIG. 3(a) and joining one end edge portion 31a and the other end edge portion 31b with a joining support portion 21a. The bottom film body 32 has a shape (circular in this embodiment) that corresponds to the shape of the bottom of the storage section 10.

[0032] First, the joining state between the end edge portions 31a, 31b of the side surface film body 31 and the joining support portion 21a will be described. FIG. 4(a) is a diagram showing the joining state of this portion, and is a cross-sectional view taken along the line AA in FIG. 1(a). As shown in FIG. 4(a), the joining support portion 21a is interposed between one end edge portion 31a and the other end edge portion 31b of the side surface film body 31, joining them together. In this embodiment, the one end edge portion 31a and the other end edge portion 31b are embedded in the joining support portion 21a in a state where they are folded so as to protrude radially outward from the outer surface of the film body 30. By joining the two in this manner, the inner and outer sides of each end edge portion 31a, 31b of the side surface film body 31 can also be covered with resin, and the entire end surface of the side surface film body 31 can be completely covered with resin.

[0033] In this embodiment, as shown in FIG. 4(a), one end edge portion 31a and the other end edge portion 31b of the side surface film body 31 are each provided with a first fold portion 31e that forms a mountain fold and a second fold portion 31f that forms a valley fold when viewed from the outer surface side of the composite container 100. In the side surface film body 31, the first fold portion 31e is located more inward than the second fold portion 31f with respect to the end faces of the end edges 31a and 31b. The first fold portion 31e and the second fold portion 31f are also located substantially parallel to and spaced a predetermined distance from the end faces (edges) of the end edges 31a and 31b, respectively. By providing these first fold portions 31e and second fold portions 31f, the end edges 31a and 31b of the side surface film body 31 are folded so as to protrude radially outward from the outer surface of the film body 30, as described above.

[0034] Furthermore, in this embodiment, when the side surface film body 31 is unfolded (see Figure 3(a)), the reinforcing support portion 21b is joined to the outer surface of the side surface film body 31 at approximately the midpoint between one end edge portion 31a and the other end edge portion 31b in the width direction (circumferential direction).

[0035] As shown in FIG. 1(b), the bottom edge portion 31c of the side surface film body 31 is joined to the upper end of the side annular frame 22b of the bottom frame body 22. The top edge portion 31d of the side surface film body 31 is joined to the lower end of the inner frame body 23a of the top frame body 23. In this embodiment, the four corners of the side surface film body 31 are rounded, that is, have rounded corners. In this embodiment, the bottom edge portion 31c and the top edge portion 31d of the side surface film body 31 are joined to the bottom frame body 22 and the top frame body 23 without being folded, unlike the one edge portion 31a and the other edge portion 31b. If the four corners of the side surface film body 31 have corners, the side surface film body 31 may peel off from the corners when the outer surface of the side surface film body 31 is joined to the inner surfaces of the side annular frame 22b of the bottom frame body 22 and the inner frame body 23a of the top frame body 23. In this embodiment, by making the four corners rounded, even when the side film body 31 is joined to the frame body 20 on only one side, the bottom edge portion 31c and top edge portion 31d of the side film body 31 can be embedded in the bottom frame body 22 and top frame body 23, covering the entire end surface and making the corners less likely to peel off.

[0036] 3(b) is joined to the inner edge of the bottom annular frame 22a of the bottom frame 22. The bottom frame 22 and the top frame 23 are each joined to the outer surface of the side film 31. The bottom frame 22 is joined to the outer surface of the bottom film 32.

[0037] In the composite container 100, the type of resin that constitutes the framework 20 is not particularly limited, but a wide variety of general-purpose resins can be used, such as polypropylene resin (homopolymer, block copolymer, random copolymer; hereinafter, PP (however, it may also be oriented polypropylene (OPP) or unoriented polypropylene (CPP))), polyethylene resin (high-density polyethylene (HDPE), low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), etc.; hereinafter, PE), polyethylene terephthalate resin (hereinafter, PET), etc., that are used as packaging container materials.

[0038] The film body 30 (31, 32) refers to a thin face body. Although it is called the film body 30, generally, anything that is film-like or sheet-like is included in the film body 30. The thickness of the film body 30 is not particularly limited, but can be, for example, about 0.01 mm or more and 1 mm or less. The thickness may be appropriately determined depending on the contents to be stored in the storage section 10, their purpose, the size of the storage section 10, etc.

[0039] The film body 30 is composed of a single-layer film or a multi-layer film. The layer structure and layer-forming materials of the film body 30 are not particularly limited, but it preferably includes at least one of a PE layer, a PP layer, a PET layer, a PA (polyamide resin / nylon (Ny)) layer, an EVOH (ethylene vinyl alcohol resin) layer, and an aluminum layer (Al layer). When the film body 30 is composed of a single-layer film, it is composed of at least one of these. When the film body 30 is composed of a multi-layer film, it is sufficient that it includes at least one of these.

[0040] The PA layer and the EVOH layer are used as gas barrier layers in food packaging films. The Al layer may be, for example, an aluminum-deposited film layer (PET-deposited layer (VM-PET)) in which aluminum is deposited on a PET layer or the like. The Al layer is used as various functional layers such as a gas barrier layer, a moisture-proof layer, and a light-shielding layer. In addition, the film body 30 may include a polystyrene (PS) layer, a cellophane (PT) layer, etc.

[0041] When the film body 30 is a multilayer film, it is sufficient to include any one of these layers, and it may also include two or more of these layers. In the case of a gas barrier layer, compatibility with polyolefin resins such as polyethylene resins and polypropylene resins may be low, resulting in poor adhesion between the two. Therefore, when a multilayer film is made of a gas barrier layer and the framework body 20, or a gas barrier layer and another polyolefin resin layer, the outermost or inner layer may contain an adhesive layer made of a modified polyethylene resin, modified polyolefin resin, or the like, to which a functional group such as Admer (registered trademark) has been introduced to impart adhesiveness to the polyolefin resin, in order to ensure adhesion (bonding and adhesiveness) between the two as needed.

[0042] Examples of layer configurations of the multilayer film include PE / EVOH / PE, PE / PA, PE / VM-PET / PE / EVOH / PE, PE / Al / PE, adhesive resin layer / EVOH, etc. Various other layer configurations used in various packaging films, such as food packaging films, can also be appropriately adopted. Regardless of the layer configuration, when using the manufacturing method described below, it is preferable that the surface to be joined to the framework 20 be a layer made of a material that is highly compatible (adhesive) with the constituent material of the framework 20.

[0043] Furthermore, in the case of a multilayer film, in addition to the above layers, functional layers such as an oxygen absorbing layer containing an oxygen scavenger such as a transition metal or a radical scavenger, or a functional component containing other components other than resin, may be provided as intermediate layers. In the above composite container 100, the entire end face of each film body 30 is covered by the framework 20. This prevents direct contact between the contents (water, oil, alcohol, etc.) contained in the storage section 10 and these layers. This prevents the components contained in these functional layers from eluting into the storage section 10. Furthermore, by covering the entire end surface of each film body 30 with the framework 20, it is possible to suppress the discharge phenomenon from the end surface when heated in a microwave oven, etc., even when the intermediate layer contains an Al layer or a layer containing a transition metal, etc. Therefore, even when the intermediate layer contains an Al layer or a functional layer containing a transition metal, it is possible to make the composite container 100 microwave-safe.

[0044] 2. Manufacturing method of composite container Next, a method for manufacturing the composite container 100 will be described. When manufacturing the composite container 100, the so-called insert molding method can be applied. A mold 50 (see FIG. 4(b)) corresponding to the framework 20 and a side surface film body 31 and a bottom surface film body 32 that have been cut into a predetermined shape in advance are prepared. Then, the side surface film body 31 and the bottom surface film body 32 are placed in predetermined positions in the mold 50 as inserts, and resin is filled into the mold 50. The composite container 100 can be obtained by this method.

[0045] As shown in Fig. 4(b), the mold 50 comprises one mold member 51 and the other mold member 52 that are separated by a separating surface, and by combining the one mold member 51 and the other mold member 52, a resin-filled portion corresponding to the shape of the framework 20 is formed. Fig. 4(b) also shows a cross-sectional side view of the mold 50 in the vicinity of a joint support portion forming region 53 having a shape corresponding to the joint support portion 21a, as the resin-filled portion. Although not shown, the mold 50 is also provided with a reinforcing support portion forming region having a shape corresponding to the reinforcing support portion 21b, a bottom frame body forming region having a shape corresponding to the bottom frame body 22, and a top frame body forming region having a shape corresponding to the top frame body 23, as resin-filled portions.

[0046] As shown in Figure 4(b), film bodies (31, 32) are placed at predetermined positions on the parting surface between one mold member 51 and the other mold member 52. Figure 4(b) shows the state in which the side film body 31 is placed at the predetermined position. The film bodies (31, 32) set at the predetermined positions in the mold 50 are sandwiched between both mold members 51, 52.

[0047] 4(b), one end edge 31a and the other end edge 31b of the side surface film body 31 are inserted into the connecting support portion forming region 53. By filling the mold 50 with resin while the one end edge 31a and the other end edge 31b of the side surface film body 31 are inserted into the connecting support portion forming region 53, the one end edge 31a and the other end edge 31b of the side surface film body 31 are joined by the connecting support portion 21a, and the side surface film body 31 is made into a cylindrical shape. Similarly, by inserting the bottom end edge 31c, the top end edge 31d, and the outer edge of the side surface film body 31 and the bottom film body 32 into the bottom frame forming region and the top frame forming region, respectively, and inserting the side surface film body 31 into the reinforcing support portion forming region, these are joined when the mold 50 is filled with resin, and the composite container 100 described above in which the film body 30 and the framework 20 are integrated can be obtained.

[0048] 4(b), in this embodiment, in the joint support portion forming region 53, a convex portion 51a that protrudes toward the other mold member 52 is provided on the parting surface of one mold member 51. In addition, a concave portion 51b is provided near this convex portion 51a on the parting surface of one mold member 51. The convex portion 51a and the concave portion 51b are arranged in this order from the end face side of the end side portions 31a, 31b on both end side portions 31a, 31b of the side surface film body 31.

[0049] Here, the action during resin filling will be described with reference to Figure 4(c). In Figure 4(c), the part below the dashed dotted line shows the state in which the side surface film body 31 is placed in the mold 50, while the part above the dashed dotted line shows the state in which the mold 50 has been filled with resin and the mold 50 has been removed. These parts correspond to Figures 4(b) and 4(a), respectively.

[0050] As shown in Figure 4(c) , when the side surface film body 31 is placed in the mold 50, one end edge portion 31a of the side surface film body 31 is pushed up by the convex portion 51a toward the other mold member 52 (see outline arrow A in Figure 4(c) ). Furthermore, a space is created between the one end edge portion 31a of the side surface film body 31 and the concave portion 51b (see outline arrow B in Figure 4(c) ). The same is true for the other end edge portion 31b. When resin is filled into the mold 50 in this state, the one end edge portion 31a and the other end edge portion 31b of the side surface film body 31 are pressed toward the parting surface of one mold member 51 at the position indicated by outline arrow B by the resin filling pressure. At this time, because the dividing surface is provided with convex portions 51a and concave portions 51b, one end edge portion 31a and the other end edge portion 31b of the side surface film body 31 are folded into the concave portions 51b, thereby forming the first folded portion 31e that has a mountain fold shape when viewed from the outer surface. Also, the one end edge portion 31a and the other end edge portion 31b of the side surface film body 31 are folded by the concave portions 51b and the convex portion 51a, thereby forming the second folded portion 31f that has a valley fold shape when viewed from the outer surface (see outline arrow C in FIG. 4(c)). By providing such convex portions 51a and concave portions 51b in one mold member 51 of the mold 50, by simply placing the side surface film body 31 cut into a predetermined shape such as a fan shape in the mold 50 as shown in FIG. 3(a), both end edge portions 31a, 31b of the side surface film body 31 are joined to the joining support portions 21a in a folded state. That is, there is no need to fold both end edge portions 31 a and 31 b of the side surface film body 31 into a predetermined shape and place it in the mold 50 in advance.

[0051] Here, a polyolefin resin such as polypropylene or polyethylene terephthalate resin is used as the filling resin material to be filled into the mold 50, and a single-layer film of a polyolefin resin layer such as a polyethylene layer or a polyethylene terephthalate resin layer, or a multilayer film with these layers or an adhesive layer arranged on the outermost surface, is used as the side film body 31 and the bottom film body 32, so that the framework body 20 and each film body (31, 32) are heat-sealed during molding, and the framework body 20 and each film body (31, 32) can be joined without using adhesives, etc.

[0052] According to the composite container 100 described above, the side surface film body 31 is cut to a predetermined shape and formed into a cylindrical shape, and the bottom surface film body 32 is provided, so that the storage section 10 is mainly constituted by the film body 30, which forms a cylindrical shape with a bottom, while the resin framework 20 can supplement the strength of the film body 30. The thickness of the side surface film body 31 can be made approximately 1 / 2 to 1 / 20 of the thickness of the framework 20, which allows for a significant reduction in the amount of resin used compared to when the entire storage section 10 is made of resin. Furthermore, the framework 20 only needs to be made thick enough to compensate for the strength shortfall caused by the film body 30 alone, so the amount of resin required for the framework 20 can be reduced.

[0053] In the above embodiment, one end edge portion 31a and the other end edge portion 31b of the side surface film body 31 are interposed between them, and are joined so that the end edge portions 31a, 31b are covered from the inner and outer surfaces by the joint support portion 21a. In this way, the entire end surface of each end edge portion 31a, 31b is completely covered. Therefore, even when the composite container 100 is used as a container for storing contents containing moisture, such as food, or liquid, it is possible to prevent the contents from leaking from the joint portion.

[0054] Because the entire end surface of the side surface film body 31 is covered by the joint support portion 21a, even if the end surface of the side surface film body 31 is a cut surface, it is possible to prevent moisture and other substances from entering through the cut surface, which would reduce rigidity. Furthermore, even if the side surface film body 31 is made of a multilayer film, the entire end surface is completely covered, which prevents problems such as the surface layer of the multilayer film easily peeling off or a decrease in the bonding strength between the one end edge portion 31a and the other end edge portion 31b and the joint support portion 21a. Furthermore, if the side surface film body 31 includes a gas barrier layer, the gas barrier layer generally contains hydrophilic groups such as OH groups, making contact with moisture (including water vapor) undesirable. However, in the composite container 100, because the entire end surface of the film body 30 is covered, it is possible to prevent direct contact between the gas barrier layer and moisture and other substances. Furthermore, as described above, it is possible to prevent the layer constituent components of the side surface film body 31 from leaking into the storage section 10 through the end edge portions 31a and 31b. Therefore, by using a film body 30 made of a multilayer film having various functional layers such as a gas barrier layer, an Al layer, and an oxygen absorbing layer, while maintaining the rigidity required of the film body 30 and the appearance of the composite container 100, it is easy to realize a layer structure that would be difficult to manufacture by blow molding or the like for the entire storage section 10.

[0055] The composite container 100 can also be manufactured by applying the insert molding method as described above. That is, the side film body 31 and bottom film body 32 having predetermined shapes are placed as inserts in predetermined positions in the mold 50 for manufacturing the framework 20, and resin is filled into the resin filling portion of the mold 50, thereby manufacturing the composite container 100 having the storage section 10 in which the resin framework 20 and the film body 30 are joined together and integrated.

[0056] In this embodiment, as described above, by simply providing the convex portion 51a and the concave portion 51b on the parting surface of one mold member 51 that constitutes the mold 50, and then placing one end edge portion 31a and the other end edge portion 31b of the side surface film body 31 at predetermined positions on the parting surface of the mold 50 and filling it with resin, both end edge portions 31a, 31b of the side surface film body 31 can be folded, and the inner and outer surfaces of each end edge portion 31a, 31b can be covered from both sides by the joining support portions 21a. Thus, according to this embodiment, even when the end edge portions 31a, 31b are joined by the joining support portions 21a in a folded state, there is no need to perform the work of folding each end edge portion 31a, 31b in advance, and manufacturing efficiency can be improved. Furthermore, by joining both end edges 31a, 31b of the side surface film body 31 in a folded state, the joint support portion 21a can be positioned between both end edges 31a, 31b of the side surface film body 31 and on one side of the side surface film body 31 (in this embodiment, the outer surface of the storage section 10), so that the joint support portion 21a does not protrude on the other side of the side surface film body 31 (in this embodiment, the inner surface).

[0057] Therefore, according to the composite container 100 and the manufacturing method of the composite container 100 of the above embodiment, by combining the resin skeleton body 20 and the film body 30, 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 skeleton body 20 and the top edge portion 31d of the film body 30.

[0058] On the other hand, for example, in a mold 60 shown in Figures 5(b) and (c), one mold member 61 is combined with the other mold member 62 to form a resin-filled portion corresponding to the shape of the framework 20, such as a joint support portion forming region 63. This mold 60 has a configuration substantially similar to the mold 50 shown in Figures 4(b) and (c) above, except that one mold member 61 does not have the above-mentioned convex portions 51a and concave portions 51b. When such a mold 60 is used, as in the above embodiment, the side film body 31 and the bottom film body 32 are placed in predetermined positions and resin is filled into the resin-filled portion of the mold 60, thereby manufacturing the composite container 100 having the storage portion 10 in which the resin framework 20 and the film body 30 are joined together and integrated.

[0059] However, in this case, as shown in FIG. 5(b), the resin is filled into the joint support portion forming region 63 of the side surface film body 31 with the entire inner surface abutting against the parting surface of one mold member 61. Therefore, while the outer surfaces of one end edge portion 31a and the other end edge portion 31b of the side surface film body 31 are covered with the resin filler that forms the joint support portion 64, the resin filler does not sufficiently extend to the inner surface, as indicated by the outlined arrow D in FIG. 5(c), making it difficult to cover the entire end surfaces of each end edge portion 31a, 31b with the resin filler. As a result, in the obtained composite container 100, the inner surfaces of the one end edge portion 31a and the other end edge portion 31b of the side surface film body 31 may be exposed and not covered with resin. If even a portion of the end surface is exposed, moisture may adhere to the end surface and enter the inside of the side surface film body 31 from the end surface, potentially reducing its rigidity. Furthermore, if the side film body 31 is made up of multiple films, problems may occur, such as the surface layer of the multilayer film becoming more susceptible to peeling or the bonding strength of the both end side portions 31 a, 31 b decreasing. In contrast, in the composite container 100 of the above embodiment, the both end side portions 31 a, 31 b are bonded in a state in which each end side portion 31 a, 31 b is embedded in the joint support portion 21 a, and therefore such problems can be prevented.

[0060] The composite container 100 and the method for manufacturing the composite container 100 described above are merely one embodiment 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 and can be modified as appropriate without departing from the spirit of the present invention. For example, in the above embodiment, the framework 20 is mainly joined to the outer surface of the film body 30 (side surface film body 31, bottom surface film body 32), but the composite container according to the present invention is not limited to this embodiment. For example, the framework 20 may be mainly joined to the inner surface of the film body 30, and the framework 20 may not be disposed on the outer surface of the storage section 10, or various embodiments may be applied, such as joining a portion of the framework 20 from the outer surface of the film body 30 and joining the remainder from the inner surface of the film body 30.

[0061] If the framework 20 is joined mainly to the outer surface of the film body 30 as in the above embodiment, the framework 20 does not protrude inside the storage section 10, and therefore, for example, when cosmetics such as yogurt, pudding, or cream are stored in the storage section 10, it is possible to prevent problems such as the contents adhering to the joint between the framework 20 and the film body 30 and making it impossible to remove the contents cleanly.

[0062] On the other hand, if the framework 20 is joined mainly from the inner surface side of the film body 30 and is configured so that the framework 20 is covered with the film body 30, the framework 20 can be made invisible from the outside. In the above embodiment, the side frame body 21 is composed of the connecting struts 21a and the reinforcing struts 21b, but if the number of reinforcing struts 21b constituting the side frame body 21 is increased in accordance with the strength (rigidity) required of the film body 30, the appearance may be impaired if the number of frame bodies 20 on the outer surface of the film body 30 increases. In such a case, it is preferable to join the two so that the frame bodies 20 are positioned mainly inside the film body 30. Furthermore, when the composite container 100 is used as a composite container for use in a bathroom or the like, water droplets may adhere to the outer surface of the composite container 100 due to condensation or the like. If the framework 20 is arranged on the outside of the composite container 100, water droplets that have adhered to the framework 20 may remain on the outer surface of the composite container 100, which may make it easier for water to seep in through the edge portions 31a, 31b of the side film body 31, etc. Therefore, for containers that are used in environments where water droplets may adhere, such as a bathroom, or where condensation is likely to occur due to the influence of atmospheric humidity, it is preferable to arrange the framework 20 inside the film body 30.

[0063] In this way, it is possible to appropriately select whether to place the framework 20 inside or outside the film body 30 depending on the contents and the desired appearance of the composite container 100.

[0064] Furthermore, in the above embodiment, one end edge portion 31a and the other end edge portion 31b of the side film body 31 are folded so as to protrude radially outward, and both end edge portions 31a, 31b are joined by the joining support portion 21a so as to cover their outer and inner surfaces. However, for example, when the framework body 20 is joined to the film body 30 so that it is positioned mainly inside the film body 30, it is sufficient to fold one end edge portion 31a and the other end edge portion 31b of the side film body 31 so as to protrude radially inward, and join them from the inner side of the side film body 31 by the joining support portion 21a so as to cover their outer and inner surfaces.

[0065] Furthermore, when folding one end edge portion 31a and the other end edge portion 31b of the side film body 31, for example, as shown in Figure 6(a), a position spaced a predetermined distance from each end edge portion 31a, 31b may be set as a folding portion 31g, and the film body 30 may be folded so as to protrude from the outer surface of the film body 30 approximately parallel to each end edge portion 31a, 31b. In this case, as shown in Figure 6(b), a mold 70 having one mold member 71 and the other mold member 72 is used, and as in the above embodiment, one end edge portion 31a and the other end edge portion 31b of the side film body 31 are inserted into the joint support portion forming region 73, and in the joint support portion forming region 73, the one end edge portion 31a and the other end edge portion 31b are pushed up toward the other mold member 72 by the convex portion 71a provided on the dividing surface of one mold member 71, and resin is filled in, so that both end edges 31a, 31b of the side film body 31 are joined to the joint support portion 74 in a folded state.

[0066] In addition, in the above embodiment, an example was described in which the side film body 31 is joined together with both end edge portions 31a, 31b of the side film body 31 folded and both its inner and outer surfaces covered by the joining support portion 21a, but in the above composite container 100, it is not necessarily necessary to fold both end edge portions 31a, 31b of the side film body 31.

[0067] 7(a), when the side surface film body 31 is rolled into a cylindrical shape, one end edge portion 31a and the other end edge portion 31b may be joined by a joint portion (joint support portion 84) that is interposed therebetween and covers both sides, including the end faces, of the one end edge portion 31a and the other end edge portion 31b of the side surface film body 31. In this case, as shown in FIG. 7(b), a mold 80 having one mold member 81 and the other mold member 82 and provided with a joint support portion forming region 83 having recesses into which resin is filled on the inner and outer surfaces of the side surface film body 31 is used, and as in the above embodiment, the one end edge portion 31a and the other end edge portion 31b of the side surface film body 31 are inserted into the joint support portion forming region 83 while being spaced a predetermined distance D1 from each other, and resin is filled into the joint support portion forming region 83, thereby joining both end edges 31a, 31b of the side surface film body 31 to the joint support portion 84.

[0068] Unlike the mold 50 used in the above embodiment and the mold 60 shown in the modified example, the mold 80 shown in Fig. 7(b) has recesses not only on the outer surfaces of the one end side portion 31a and the other end side portion 31b but also on the inner surfaces thereof. Therefore, if the one end side portion 31a and the other end side portion 31b are inserted too deeply into the joint support portion forming region 83, the one end side portion 31a and the other end side portion 31b may bend into an unintended shape due to the resin filling pressure. In this way, when the joint support portion 21a is formed so as to protrude on both sides of one end edge portion 31a and the other end edge portion 31b, and when resin is filled on both sides of one end edge portion 31a and the other end edge portion 31b, it is preferable to appropriately adjust the insertion depth into the joint support portion forming region 83, the above-mentioned specified distance D1 between the one end edge portion 31a and the other end edge portion 31b, the resin filling pressure, and the distance (specified distance D2) between the gate portion for filling resin into the mold 80 and the one end edge portion 31a and the other end edge portion 31b, depending on the rigidity of the side film body 31, etc.

[0069] However, in this case, unlike the above embodiment, the thickness of the joint support portion 84 becomes thicker. Therefore, from the viewpoint of reducing the amount of resin, it is preferable to provide the joint support portion 21a on one side of the side surface film body 31, as shown in the above embodiment, and fold one end edge portion 31a and the other end edge portion 31b so as to be embedded in the joint support portion 21a.

[0070] Furthermore, in the above embodiment, the side film body 31 with rounded corners and the circular bottom film body 32 are joined to the bottom frame body 22 and the top frame body 23, respectively, making it difficult for the side film body 31 and the bottom film body 32 to peel off from the joints with the bottom frame body 22 and the top frame body 23. However, similar to the one end edge portion 31a and the other end edge portion 31b, it is also preferable to join these parts so that their inner and outer sides are covered by the frame bodies (22, 23). In this case, the joint end portions may be folded and embedded within the frame bodies, joining and integrating the frame body 20 and the film bodies (31, 32).

[0071] In the above embodiment, an example has been shown in which the storage section 10 is formed in a cup shape with its bottom surface 11 and top surface 13 being circular, but the specific shape of the storage section 10 is not particularly limited. For example, it may be formed in a deep dish shape or a bottle shape, and the shapes of the bottom surface 11 and top surface 13 are not limited to circles but may be square, rectangular, polygonal, etc.

[0072] In the above embodiment, one side surface film body 31 is rolled up and one end edge portion 31a is joined to the other end edge portion 31b, but the number of side surface film bodies 31 used to form the side surface 12 of the storage section 10 is not particularly limited, and two or more side surface film bodies 31 may be used and the end edges of each side surface film body 31 joined to obtain the film body 30. Furthermore, one side surface film body 31 may have cut portions, and the cut edges may be joined to each other using part of the side framework body 21, as in the above embodiment. In this way, storage sections 10 of various shapes can be formed.

[0073] 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 film body 32, but the shape of the bottom frame assembly 22 is not particularly limited. The bottom frame assembly 22 may be provided with reinforcing ribs such as crosses, or the entire bottom surface 11 may be formed from a resin bottom material, and the configuration of the bottom surface 11 is not particularly limited. Note that when the entire bottom surface 11 is formed from a resin bottom material, there is no need to use the bottom film body 32, and such an embodiment is also included in the composite container of the present invention.

[0074] Furthermore, in the above embodiment, the side framework 21 is composed of the connecting struts 21a and the reinforcing struts 21b, but in the composite container of the present invention, the framework only needs to have a joint between one edge of the film body and the other edge of the film body to join them, and other aspects are optional. In other words, if the film body 30 itself meets the required strength, there is no need to provide the reinforcing struts 21b, and the side framework 21 may be composed only of the connecting struts 21a. Furthermore, the specific configurations of the side framework 21, bottom framework 22, and top framework 23 are also optional, as long as any of them has the joints referred to in the present invention.

[0075] Similarly, the outer edge of the bottom film body 32 may be folded in the same manner as one end edge portion 31a and the other end edge portion 31b of the side film body 31, and the two may be joined by being embedded in the bottom annular frame 22a, or the inner surface of the outer edge may be left unfolded and covered by the bottom annular frame 22a. The same applies to the bottom end edge portion 31c and the top end edge portion 31d of the side film body 31. [Explanation of symbols]

[0076] 10: Storage section 11: Bottom 12: Side 13: Top 20: Skeleton body 21: Side frame 21a: Joint support section (joint section) 21b: Reinforcement support section 22: Bottom frame 22a: Bottom ring frame 22b: Side ring frame 22c: Basal bone junction 22d: Connecting part 23: Celestial skeleton body 23a: Inner frame 23b: Flange part 23c: Outer frame 23d: Inner rib 23e: Peripheral rib 23f: Circular convex rib 30: Film body 31: Side film body 31a: Edge 31b: Edge 31c: Bottom edge 31d: Top edge 31e: First bending part 31f:Second bending part 31g: Bent part 32: Bottom film body 50: Mold 51: One mold member 51a: Convex part 51b: recess 52: Other mold member 53: Joint support formation area (joint formation area) 60: Mold 61: Mold material 62: Mold material 63: Joint support formation area (joint formation area) 64: Joint support section 70: Mold 71: One mold member 71a: Convex part 72: Other mold member 73: Joint support formation area (joint formation area) 74: Joint support section 80: Mold 81: One mold member 82: Other mold member 83: Joint support portion forming area (joint portion forming area) 84: Joint support portion 100: Composite container

Claims

1. a storage section having a bottom surface and a side surface, the storage section being configured using a resin framework and a film body whose edge portions are joined to the framework; the framework has a joint portion interposed between one end edge portion and another end edge portion of the film body and covering the entire end surfaces of the one end edge portion and the other end edge portion, The end portions at the joints are folded to protrude from the outer surface of the film body and are embedded in the framework body.

2. 2. The composite container according to claim 1, wherein the film body is a single-layer film or a multi-layer film and includes at least one layer of a polyethylene resin layer, a polypropylene resin layer, a polyethylene terephthalate resin layer, a polyamide resin layer, an ethylene vinyl alcohol resin layer, and an aluminum layer.

3. The framework comprises a bottom framework that forms the outer edge of the bottom surface, a top framework that forms the outer edge of the top surface of the storage section, and a side framework that includes the joint and is connected to the bottom framework and the top framework, the side surface of the storage section is configured by the side framework and a side surface film body that forms a cylindrical shape by joining the one end edge portion and the other end edge portion to the joint portion, the bottom surface of the storage section is constituted by the bottom frame body and a bottom film body whose outer edge end portion is joined to the bottom frame body, A composite container as described in claim 1 or 2, wherein the bottom edge portion of the cylindrical side film body is joined to the bottom frame body, and the top edge portion is joined to the top frame body, and the end faces of the bottom edge portion and the top edge portion are entirely covered by the bottom frame body and the top frame body, respectively.

Images