JP2023034793A - Composite container and method for manufacturing composite container - Google Patents

Abstract

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

Description

The present invention relates to a composite container and a method for manufacturing a composite container.

In recent years, efforts have been made to reduce the amount of resin in disposable containers in order to reduce the burden on the natural environment caused by plastic waste such as microplastics. Specific efforts include reducing the amount of resin used in plastic containers and replacing plastic products with paper products. Furthermore, a composite container or the like in which a plastic container and a paper member are combined has been proposed.

For example, Patent Document 1 proposes a composite container in which a resin container and a paper sleeve (reinforcing member) are combined. In the composite container, the amount of resin is reduced by providing a thin portion having a thickness of 0.01 mm or more and 0.09 mm or less in the body of the resin container. However, if such a thin-walled portion is provided in the barrel, the barrel is easily deformed and cannot be gripped. Therefore, in the resin container, a flange portion connected to the body portion, a thick portion connected to the flange portion at the body portion, and a projecting portion projecting radially outward from the thick portion are provided. The thin portion is arranged closer to the bottom than the thick portion. By inserting the body of the resin container into the cylindrical sleeve made of paper and supporting the sleeve on the protruding portion, the resin container and the paper sleeve can be easily attached, and The sleeve reinforces the rigidity of the resinous container, which is reduced by the thin-walled portion.

JP 2021-116122 A

According to the composite container disclosed in Patent Literature 1, the amount of resin in the body is greatly reduced by obtaining rigidity from the paper sleeve. However, the upper portion of the body portion is provided with a thick portion, and the bottom portion is also made thicker than the thin portion in order to maintain a predetermined strength. Therefore, there are relatively many parts made of resin, and further reduction of the amount of resin used is required. Furthermore, in the composite container, it is necessary to separately prepare the resin container and the paper sleeve, and then attach the paper sleeve to the resin container. Therefore, the manufacturing process is complicated, and an improvement in manufacturing efficiency is required. Furthermore, in the composite container disclosed in Patent Document 1, a protruding piece is provided at the upper end of the paper sleeve, and the protruding piece is folded to form an engaging portion, which is attached to the upper end of the resin container. However, there is a possibility that the paper sleeve may come off from the resin container during use. In addition, when liquids such as beverages are contained in the composite container, water adheres to the upper end of the paper sleeve, and if the paper sleeve becomes soggy, there is a risk that the paper sleeve will become easier to come off from the resin container. be.

Therefore, an object of the present invention is to reduce the amount of resin and improve manufacturing efficiency by combining a resin frame and a paper tubular body, and to combine the resin frame and the paper cylinder. An object of the present invention is to provide a composite container and a method for manufacturing the same, which can maintain a good joint state with the top edge portion of a cylindrical body.

In order to solve the above-mentioned problems, a composite container according to the present invention has a bottom surface and a side surface, and has a storage part with an open top surface. and the frame body constitutes the outer edge portion of the top surface and joins the top end side portion of the cylindrical body from both sides of the inner surface and the outer surface. .

In the composite container according to the present invention, the cylindrical body is formed into a cylindrical shape by joining the edges of one or more paper face bodies together, and the frame body is the side surface of the storage part. It is preferable that the paper face piece has a strut portion that is joined to the paper face piece in (1), and that one edge and the other edge of the paper face piece are joined to each other at the strut portion.

In the composite container according to the present invention, it is preferable that the cylindrical body is constructed using one or a plurality of paper facepieces having a polyolefin resin layer on the surface thereof, and the frame body is constructed of polyolefin resin. .

In order to solve the above-mentioned problems, a method for manufacturing a composite container according to the present invention includes a container having a bottom surface and a side surface and an opening at the top surface, the container having a frame body made of resin and a container made of paper. In the manufacturing method of a composite container configured using a cylindrical body, the frame body constitutes the outer edge portion of the top surface, and the top end side portion of the cylindrical body is formed on the inner surface and the outer surface. A paper face piece for forming the cylindrical body is installed at a predetermined position as an insert in a mold for molding the frame body, and from the bottom side By pouring a resin into the mold, the composite container in which the framework and the cylindrical body are joined is obtained.

According to the composite container according to the present invention, by configuring the storage section using the resin frame body and the paper tubular body, compared to the case where the entire storage section is made of resin, the resin used amount can be greatly reduced. In addition, since the framework may have a thickness sufficient to compensate for the strength that is lacking in the paper cylindrical body, the amount of resin required for the framework can be reduced.

Here, the top frame body is joined to the top edge portion of the cylindrical body made of paper. The top frame body is likely to be subjected to force when contents are taken in and out of the storage section, which joins the top end portion of the tubular body from both the inner surface and the outer surface thereof. However, in the composite container according to the present invention, the top frame joins the top edge portion of the cylindrical body from both the inner surface and the outer surface. Therefore, even when such a force is applied, a good bonding state can be maintained between the two.

Further, when the composite container is applied to a cup container for containing liquid such as beverage, moisture may adhere to the outer edge portion of the top surface. At the joint between the ceiling framework and the tubular body, moisture may enter the top edge of the tubular body through a small gap at the joint interface between the two. There is a risk that the top edge of the cylindrical body will absorb moisture and become soggy. However, in the composite container according to the present invention, the top edge portion of the cylindrical body is joined from both the inner surface and the outer surface of the top frame body, so that water is allowed to enter from the end surface of the top edge of the cylindrical body to the inside. Absorption can be suppressed and the strength of the cylindrical body can be maintained. Therefore, even when the content is a liquid or the like, it is possible to maintain a good bonding state between the two.

Furthermore, for example, by adopting an insert molding method and setting a paper facepiece for forming a cylindrical body in a predetermined position in a mold for manufacturing a resin framework and filling the resin with the mold, Since the top frame can be joined to the top edge of the cylindrical body, the work of separately manufacturing and assembling the resin-made part and the paper-made part becomes unnecessary, and the manufacturing efficiency can be improved. .
As described above, according to the composite container and the method for manufacturing a composite container according to the present invention, it is possible to reduce the amount of resin and improve the manufacturing efficiency by combining a resin framework and a paper cylindrical body, and , the joint state between the resin framework and the top edge portion of the paper cylinder can be maintained satisfactorily.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure for demonstrating the composite container of embodiment of this invention, (a) is a top view of the said composite container, (b) is a partial sectional view of the said composite container. However, the cross-sectional portion represents the AA cross section of (a). FIG. 2 is a side cross-sectional view showing the top surface portion of the composite container shown in FIG. 1, (a) is a side cross-section at a position corresponding to the area surrounded by B in FIG. 1 (b), and (b) is a side frame body It is a side cross-section of a position that does not exist. 1. It is a figure which shows the paper-made face piece which comprises the cylindrical body of the compound container shown in FIG. 1, (a) shows a side paper-made face piece, (b) shows a bottom face piece. FIG. 4 is a side cross-sectional view as a comparative example for comparison with the side cross-sectional structure of the top surface portion of the composite container of the present embodiment shown in FIG. 3;

A composite container and a method for manufacturing a composite container according to embodiments of the present invention will be described below with reference to the drawings.

1. Composite Container A schematic configuration of a composite container 100 of the present embodiment will be described with reference to FIG. The composite container 100 has a bottom surface 11 and a side surface 12, and a housing portion 10 with an open top surface 13, as shown in FIG. 1(b). The housing portion 10 has a cup shape, and the bottom surface 11 and the top surface 13 are circular, and the top surface 13 has a larger diameter than the bottom surface 11 . The bottom surface 11 and the top surface 13 are coaxial, and the line passing through the respective centers is defined as the central axis O. As shown in FIG. 1(a) is a top view showing the composite container 100, and FIG. 1(b) is a partial sectional view of the composite container 100. FIG.

The composite container 100 is a hybrid container in which a resin member and a paper member are integrated. Specifically, the housing portion 10 has a frame portion (hereinafter referred to as a frame body 20) made of a resin member, and a cylindrical body 30 made of paper is joined to the frame body 20 to form the frame body 20. covered. Hereinafter, regarding the frame body 20, the part forming the frame of the side portion of the housing portion 10 is referred to as the side frame body 21, and the portion forming the frame of the bottom portion is referred to as the bottom frame body 22, which forms the frame of the top portion. The part that does is called a top frame body 23 .

The side frame body 21 includes four struts 21 a each having one end connected to the bottom frame body 22 and the other end connected to the top frame body 23 . These four pillars 21a are arranged at regular intervals.

The bottom frame body 22 includes a bottom frame body 22a forming an outer edge portion of the bottom surface 11 of the housing portion 10, and a reinforcing portion 22b for supplementing the strength of the bottom surface 11. As shown in FIG. The bottom frame body 22a is configured as an annular frame having an L-shaped cross section. The reinforcing portion 22b has a cross shape centered on the central axis O. As shown in FIG. The reinforcing portion 22b is a plate-like member extending at intervals of 90 degrees from the center of the bottom surface 11. The ends of the reinforcing portion 22b are connected to the support columns (21a) and to the bottom frame 22a. As shown in FIG. 2(a), each support pillar 21a is joined to the inner surface of a side paper face member 31 (see FIG. 3(a)) that constitutes the cylindrical body 30. As shown in FIG.

The top frame body 23 includes a top frame body 23a forming an outer edge portion of the top surface 13 of the housing portion 10, and a flange portion 23b projecting outward from the top frame body 23a. The top frame body 23a is configured in a ring frame shape having a predetermined length in the height direction. A flange portion 23b is connected to the top end of the top frame body 23a. As shown in FIGS. 2A and 2B, the top frame body 23a has an inner surface portion 23c joined to the inner surface side of the top edge portion 31d of the cylindrical body 30, and an outer surface portion of the top edge portion 31d. The inner surface portion 23c and the outer surface portion 23d are joined so as to sandwich the top edge portion 31d of the tubular body 30 between the inner surface portion 23c and the outer surface portion 23d.

In this embodiment, the cylindrical body 30 is formed by rolling a fan-shaped side paper face piece (paper face piece) 31 shown in FIG. It is made into a cylindrical shape. One edge 31a and the other edge 31b of the side paper-made face piece 31 are joined at one of the four support sections 21a provided on the side frame body 21. As shown in FIG.
Further, in this embodiment, the cylindrical body 30 is provided with a circular bottom paper face piece 32 for covering the bottom frame body 22 shown in FIG. 2(b). As shown in FIG. 1(b), the bottom edge 31c of the side paper face piece 31 (the bottom edge of the cylindrical body 30) is joined to the bottom frame body 22. As shown in FIG. Further, the outer peripheral portion of the bottom paper-made face piece 32 is joined to the bottom frame 22a of the bottom frame body 22, and the inner surface portion is joined to the reinforcing portion 22b.

In the composite container 100, the type of resin constituting the framework 20 is not particularly limited, but polypropylene (homopolymer, block copolymer, random copolymer), polyethylene (high general-purpose resins such as high-density polyethylene, low-density polyethylene, etc.) and polyethylene terephthalate resin can be widely used. In particular, olefin-based resins such as polypropylene and polyethylene are more preferable in terms of adopting the manufacturing method described below.

The paper-made face pieces (31, 32) constituting the cylindrical body 30 may be formed thinly and flatly by agglutinating plant fibers or other fibers. Composite paper may be used, and functional paper imparted with functions such as water resistance and oil resistance may also be used. The basis weight of the paper used can be designed appropriately. For example, paper having a basis weight of 100 g/m ² or more and 600 g/m ² or less, preferably 250 g/m ² or more and 400 g/m ² or less can be used. In particular, in adopting the production method described later, it is more preferable to use a laminated paper that is imparted with functions such as water resistance and oil resistance by laminating an olefin resin layer such as polyethylene resin on the surface layer.

2. Method for Manufacturing Composite Container Next, a method for manufacturing the composite container 100 will be described. When manufacturing the composite container 100, so-called insert molding can be employed. A mold suitable for the framework 20, and a side paper face piece 31 and a bottom paper face piece 32 cut into predetermined shapes in advance are prepared. Then, the side paper face piece 31 and the bottom paper face piece 32 are placed in the mold as inserts at predetermined positions, and the resin is poured into the framework 20 from the bottom side. In this mold, the resin is poured from the center position of the reinforcing portion 22b of the bottom frame body 22. As shown in FIG.

As described above, the bottom frame body 22, the side frame bodies 21 and the top frame body 23 are connected to each other. Therefore, the resin poured into the mold from a position corresponding to the center position of the reinforcing portion 22b spreads radially outward and splits in four directions, passing through the bottom frame 22a, the side frame 21, and the top frame. It flows in order of 23.

At this time, a polyolefin resin such as polypropylene is used as the filling resin material, and a polyolefin resin layer such as a polyethylene layer is formed on at least the surface of the side paper face piece 31 and the bottom paper face piece 32 which is joined to the framework 20 . By using the laminated paper in which is laminated, the frame body 20 and each paper face piece (31, 32) are heat-sealed during the insert molding, and the frame body 20 and each paper face piece ( 31, 32) can be joined.

According to the above-described composite container 100, while the cylindrical body 30 formed by cylindrically forming the side paper face piece 31 mainly constitutes the storage section 10, the strength of the cylindrical body 30 is supplemented by the resin frame body 20. can be done. Therefore, the amount of resin to be used can be greatly reduced compared to the case where the entire housing portion 10 is made of resin. Furthermore, the frame body 20 may have a thickness sufficient to compensate for the strength that is lacking with the paper cylindrical body 30 alone, so the amount of resin required for the frame body 20 can be reduced.

Further, in the composite container 100, the top frame 23 is joined to the top edge 31d of the tubular body 30 made of paper. Force is likely to be applied to the outer edge portion of the top surface 13 when contents are taken in and out of the container 10 . In the composite container 100, the top edge 31d of the tubular body 30 is sandwiched between the inner surface portion 23c and the outer surface portion 23d of the top frame body 23a from both sides of the inner surface and the outer surface. Detachment from the body 23 can be prevented, and a good joint state between the two can be maintained.

Further, when the composite container 100 is applied to a cup container for containing liquid such as a beverage, moisture may adhere to the outer edge portion of the top surface 13 . Side sectional views shown in FIGS. 4(a) and 4(b) show the configuration of a composite container as a comparative example for comparison with the composite container 100 described above. The same symbols are attached to the same configurations as those of the composite container 100 of the present embodiment. At the joint between the top frame 23 and the tubular body 30, for example, when the top frame 23a has only the inner surface portion 23c and does not have the outer surface portion 23d, as shown in FIGS. If water adheres to the top edge 31d of the tubular body 30, the moisture may enter through a small gap at the joint interface between the top edge 31d of the tubular body 30 and the top frame 23a. For example, even if the side paper face piece 31 has a polyolefin resin layer on the surface layer and has water resistance, the side paper face piece 31 can be obtained by cutting such laminated paper into a predetermined shape. Therefore, the end face of the top edge 31d is often not covered with such a waterproof layer. When water enters from the cut end face, the side paper face piece 31 absorbs the water and becomes soggy. However, in the composite container 100, the inner surface and the outer surface of the top edge 31d of the cylindrical body 30 are covered with the inner surface portion 23c and the outer surface portion 23d, and then joined together. Therefore, in the above composite container 100, it is possible to suppress the intrusion of moisture into the inside of the side paper face piece 31 from the top edge 31d of the cylindrical body 30, so that the cylindrical body 30 does not swell and the composite container 100 It is possible to maintain a good bonding state between both while maintaining the strength required for.

Furthermore, if the composite container 100 is manufactured by an insert molding method, each paper face piece (31, 32) is set at a predetermined position as an insert in a mold for manufacturing the frame body 20, and filled with resin. As a result, the top frame 23 is joined to the top edge 31d of the cylindrical body 30, and the side frame 21 and the bottom frame 22 are joined to the paper face pieces (31, 32), respectively. 100 can be manufactured. Further, the cylindrical body 30 is formed by cylindrically forming one sheet of side paper face piece 31. As described above, one end side 31a and the other end side 31b of the side face paper face piece 31 are separated from each other. are joined at one support 21a among the four support 21a constituting the side frame body 21, the step of joining the end sides of the cylindrical body 30 to each other is not required. Therefore, when manufacturing the composite container 100, it is not necessary to separately manufacture and assemble the resin framework 20 and the paper cylindrical body 30, thereby improving the manufacturing efficiency.

Therefore, according to the composite container 100 and the manufacturing method of the composite container 100 of the above-described embodiment, by combining the resin framework 20 and the paper cylindrical body 30, the amount of resin can be reduced and the manufacturing efficiency can be improved. In addition, the joint state between the frame body 20 made of resin and the top edge 31d of the tubular body 30 made of paper can be maintained in a good condition.

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 embodiments. Changes can be made as appropriate without departing from the gist of the invention. For example, in the above embodiment, the framework 20 is joined to the inside of the tubular body 30 and the framework 20 is covered with the tubular body 30, but the composite container according to the present invention is limited to this aspect. not to be For example, the frame body 20 may be joined to the outside of the cylindrical body 30 so that the frame body 20 is not arranged inside the housing portion 10, or a portion of the frame body 20 (for example, a portion of the strut portion 21a) may be attached. Alternatively, various aspects can be applied, such as the bottom frame body 22 etc.) being joined from the outside of the tubular body 30 and the rest being joined from the inside of the tubular body 30 . If the frame body 20 is covered with the cylindrical body 30 as in the above embodiment, the frame body 20 is not visible from the outside, and various designs can be easily applied to the surface of the cylindrical body 30, for example. Therefore, it is suitable from the point of view of obtaining a highly designed appearance. On the other hand, if the frame body 20 is joined to the cylindrical body 30 from the outside, the frame body 20 does not exist inside the storage section 10, so that cosmetics such as yogurt, pudding, or cream are stored in the storage section 10, for example. It is possible to suppress the problem that the contents sometimes adhere to the joint portion between the frame body 20 and the cylindrical body 30 and the contents cannot be taken out cleanly. Depending on the content, it is possible to appropriately select whether to arrange the frame body 20 inside or outside the tubular body 30 .

Further, in the above-described embodiment, an example was shown in which the bottom surface 11 and the top surface 13 of the housing portion 10 were formed in a circular cup shape, but the specific shape of the housing portion 10 is not particularly limited. . For example, it may be formed in the shape of a deep plate or in the shape of a bottle, and the shape of the bottom surface 11 and the top surface 13 is not limited to circular, and may be square, rectangular, or polygonal. good too.

In the above-described embodiment, one sheet of side paper face piece 31 is rolled up and one end side 31a and the other end side 31b are joined. The number of side paper face pieces 31 used in 1 is not particularly limited, and two or more side face pieces 31 may be used and the cylindrical body 30 may be obtained by joining the edges of the side paper face pieces 31 together. In addition, one sheet of side paper face piece 31 may have a notched portion, and the cut edges may be joined using a part of the side frame body 21 as in the above-described embodiment. . By doing so, it is possible to form the accommodating portion 10 having various shapes.

2A and 2B, the inner surface portion 23c and the outer surface portion 23d provided on the top frame 23a are positioned substantially at the same position on the inner surface and the outer surface of the side paper surface member 31. The lower end (position on the side of the bottom surface 11) has a substantially line-symmetrical shape, but the structure of the top frame body of the composite container according to the present invention is limited to the embodiment shown in FIGS. 2(a) and 2(b). isn't it. For example, the shapes of the inner surface portion 23c and the outer surface portion 23d do not need to be substantially line symmetrical with respect to the side paper face piece 31. It may be positioned above (on the top surface 13 side) or below (on the bottom surface 11 side) in the direction of , and is not particularly limited.

Furthermore, in the above-described embodiment, the bottom frame 22 and the bottom paper face piece 32 are used to configure the bottom surface 11 of the housing portion 10, but the shape of the bottom frame body 22 is not particularly limited. If the strength of the bottom surface 11 required for the composite container 100 can be maintained, there is no need to provide the reinforcing portion 22b. Moreover, the entire surface of the bottom surface 11 may be made of a resin bottom plate material, and the configuration of the bottom surface 11 is not particularly limited.

If the composite container 100 is manufactured by insert molding, the manufacturing efficiency is also good. may be joined by bonding using an adhesive or the like, or by locally applying heat to weld them.

10 : Housing portion 11 : Bottom surface 12 : Side surface 13 : Top surface 20 : Frame body 21 : Side frame body 21a : Post part 22 : Bottom frame body 22a : Bottom frame body 22b : Reinforcing part 23 : Top frame body 23a : Top frame Body 23b: flange portion 23c: inner surface portion 23d: outer surface portion 30: cylindrical body 31: side paper-made surface body 31a: one edge 31b: other edge 31c: bottom edge 31d: top edge 32: bottom paper Face piece 100: composite container O: central axis

Claims (4)

It has a bottom surface and a side surface, and has a storage part with an open top surface, and the storage part is configured using a resin framework and a paper tubular body,
The composite container, wherein the frame body constitutes an outer edge portion of the top surface and joins the top edge portion of the cylindrical body from both sides of the inner surface and the outer surface thereof. The tubular body is formed into a tubular shape by joining the edges of one or more paper facepieces,
The frame body has a strut part joined to the paper facepiece on the side surface of the storage part,
2. The composite container according to claim 1, wherein one edge and the other edge of said paper face piece are joined to each other at said strut portion. 3. The composite according to claim 1 or 2, wherein the cylindrical body is constructed using one or a plurality of paper facepieces having a polyolefin resin layer on the surface thereof, and the frame body is composed of a polyolefin resin. container. A method for manufacturing a composite container having a bottom surface and a side surface and having an opening at the top surface, wherein the storage unit is configured by using a resin frame body and a paper tubular body,
The frame body includes a top frame body that forms the outer edge portion of the top surface and joins the top end side portion of the cylindrical body from both sides of the inner surface and the outer surface,
A paper face piece for forming the cylindrical body is placed as an insert in a predetermined position in a mold for molding the framework, and resin is poured into the mold from the bottom side to form the framework. A method for manufacturing a composite container, wherein the composite container is obtained by joining a body and the cylindrical body.

Images