Packaging containers and blank materials used in the manufacture of packaging containers

Abstract

The present invention provides a packaging container that is resistant to deformation, formed using sheet material, and a blank material used in the manufacture of packaging containers. [Solution] A packaging container comprising: a box-shaped first and second storage section having a bottom, four side sections, and a rectangular open surface; a strip-shaped connecting piece connecting one side of the open surface of the first storage section and one side of the open surface of the second storage section; a main body having a rectangular annular flat flange section extending outward from the periphery of the open surfaces of the first and second storage sections and surrounding the first storage section, the second storage section, and the connecting piece; and a liner material that seals the inner surfaces of the first and second storage sections and the outer surfaces of the connecting piece and the flange section, wherein the main body is made of a single sheet material, and the sheet material is folded back along the four sides of the flange section and double-layered at the flange section.

Description

Technical Field

[0001] The present invention relates to a packaging container formed of a sheet material, and a blank material used for manufacturing the packaging container.

Background Art

[0002] In recent years, from the perspective of environmental protection and resource conservation, reduction of the amount of resin used in packaging containers has been demanded, and various packaging containers using paper have been studied. Such a packaging container is composed of a paper container main body assembled from one blank, and an internal protective film layer that can be peeled off from the paper container main body (Patent Documents 1 and 2).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] When a paper packaging container is used as a lunch box container or the like, the packaging container may deform during use as it cannot withstand the weight of the contents, making it difficult to handle in some cases.

[0005] Therefore, an object of the present invention is to provide a packaging container that is formed using a sheet material and is less likely to deform, and a blank material used for manufacturing the packaging container.

Means for Solving the Problems

[0006] A packaging container according to one embodiment of the present invention comprises a box-shaped first and second storage section having a bottom, four side sections, and a rectangular open surface; a strip-shaped connecting piece connecting one side of the open surface of the first storage section and one side of the open surface of the second storage section; a main body having a rectangular annular flat flange section extending outward from the periphery of the open surfaces of the first and second storage sections and surrounding the first storage section, the second storage section, and the connecting piece; and a liner material that seals the inner surfaces of the first and second storage sections and the outer surfaces of the connecting piece and the flange section, wherein the main body is made of a single sheet material, and the sheet material is folded back along the four sides of the flange section and overlaps twice at the flange section.

[0007] A blank material used in the manufacture of a packaging container according to one embodiment of the present invention comprises: a ring portion having a rectangular annular shape corresponding to the outer surface of the flange portion; a connecting panel corresponding to a connecting piece that connects a pair of opposing sides on the inner periphery of the ring portion, dividing the inside of the ring portion into a rectangular first region and an adjacent rectangular second region; a pair of first reinforcing panels connected to each of the four sides of the outer periphery of the ring portion that are parallel to the adjacent directions of the first and second regions, and corresponding to a folded portion of the flange portion; a pair of second reinforcing panels connected to each of the four sides of the outer periphery of the ring portion that are adjacent to the first sides, and corresponding to another portion of the folded flange portion; and a pair of first side panels connected to each of the first reinforcing panels, provided corresponding to the first and second regions, and corresponding to the side portions of adjacent first and second storage portions. The structure comprises a flannel and a pair of second side panels, a pair of third side panels connected to each of the second reinforcing panels and corresponding to a portion of the side portions of the first and second storage sections, a pair of fourth side panels connected to connecting panels within the first and second regions and corresponding to a portion of the side portions of the first and second storage sections, a pair of first bottom panels connected to each of the pair of first side panels and corresponding to a portion of the bottom portion of the first storage section, a pair of second bottom panels connected to each of the pair of second side panels and corresponding to a portion of the bottom portion of the second storage section, a pair of third bottom panels connected to each of the pair of second side panels and corresponding to a portion of the bottom portion of the first and second storage sections, and a pair of fourth bottom panels connected to each of the pair of fourth side panels and corresponding to a portion of the bottom portion of the first and second storage sections.

[0008] A packaging container according to one embodiment of the present invention comprises a box-shaped storage section having a bottom, side sections, and a rectangular open surface; a main body having a rectangular annular flat flange section extending outward from the periphery of the open surface and surrounding the storage section; and a liner material that seals the inner surface of the storage section and the outer surface of the flange section. The main body is made of a single sheet material, and the sheet material is folded back along the four sides of the flange section, resulting in a double overlap at the flange section.

[0009] A blank material used in the manufacture of a packaging container according to one embodiment of the present invention comprises: a ring portion having a rectangular annular shape corresponding to a flange portion; a pair of first reinforcing panels connected to each of a pair of first sides of the four sides of the outer periphery of the ring portion and corresponding to a part of the folded flange portion; a pair of second reinforcing panels connected to each of a pair of second sides adjacent to the first sides of the four sides of the outer periphery of the ring portion and corresponding to another part of the folded flange portion; a pair of first side panels connected to each of the first reinforcing panels and corresponding to a part of the side surface of the housing portion; a pair of second side panels connected to each of the second reinforcing panels and corresponding to another part of the side surface of the housing portion; a first bottom panel connected to each of the pair of first side panels and corresponding to a part of the bottom surface of the housing portion; and a pair of second bottom panels connected to each of the pair of second side panels and corresponding to another part of the bottom surface of the housing portion. [Effects of the Invention]

[0010] According to the present invention, it is possible to provide a packaging container that is resistant to deformation and formed using a sheet material, and a blank material used in the manufacture of the packaging container. [Brief explanation of the drawing]

[0011] [Figure 1] Perspective view of a packaging container according to the first embodiment [Figure 2] Figure 1 shows a perspective view of the packaging container from below. [Figure 3] Cross-sectional view along the X-X' line shown in Figure 1. [Figure 4] Front view of the packaging container shown in Figure 1. [Figure 5] Developed view of blank material used in the manufacture of packaging containers shown in Figure 1. [Figure 6] A perspective view from below of a packaging container according to Modification 1 of the First Embodiment. [Figure 7] Front view of the packaging container shown in Figure 6. [Figure 8] Developed view of blank material used in the manufacture of packaging containers shown in Figure 6. [Figure 9]Bottom perspective view of the packaging container according to Modification 2 of the first embodiment [Figure 10] Front view of the packaging container shown in Figure 9 [Figure 11] Development view of the blank material used for manufacturing the packaging container shown in Figure 9 [Figure 12] Development view of another example of the blank material used for manufacturing the packaging container according to Modification 2 of the first embodiment [Figure 13] Perspective view of the packaging container according to the second embodiment [Figure 14] Cross-sectional view taken along the Y-Y' line shown in Figure 13 [Figure 15] Development view of the blank material used for manufacturing the packaging container shown in Figure 13 [Figure 16] Development view of the blank material according to the reference example [Mode for Carrying Out the Invention]

[0012] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In each figure, a broken lead line indicates a portion hidden on the back surface or behind the led-out location.

[0013] (First Embodiment) Figure 1 is a perspective view of the packaging container according to the first embodiment, Figure 2 is a bottom perspective view of the packaging container shown in Figure 1, Figure 3 is a cross-sectional view taken along the X-X' line shown in Figure 1, and Figure 4 is a front view of the packaging container shown in Figure 1.

[0014] The packaging container 100 includes a sheet material 1 and a liner material 2.

[0015] The sheet material 1 is a sheet serving as the base material of the packaging container 100, and constitutes the main body portion 10. The main body portion 10 is composed of one sheet material 1, and has a first storage portion 11, a second storage portion 12, a strip-shaped connection piece 13 that connects the first storage portion 11 and the second storage portion 12, and a flange portion 14 that surrounds the first storage portion 11, the second storage portion 12, and the connection piece 13.

[0016] The first storage section 11 and the second storage section 12 are box-shaped parts with open surfaces. More specifically, they have a rectangular shape in plan view and each has a bottom surface 15a and 15b, four side surfaces 16a to 16d and 16e to 16h, and rectangular open surfaces 17a and 17b, respectively. The first storage section 11 and the second storage section 12 each contain contents such as food. The volumes of the first storage section 11 and the second storage section 12 may be the same or different, as shown in Figure 1.

[0017] The connecting piece 13 connects one side of the open surface 17a of the first storage section 11 that faces the second storage section 12, and one side of the open surface 17b of the second storage section 12 that faces the first storage section 11. The packaging container 100 is partitioned by the side surface 16d of the first storage section 11 and the side surface 16h of the second storage section 12, which share an edge with the connecting piece 13. Therefore, there is no need to use separate trays or the like to restrict the movement of the contents stored in the packaging container 100.

[0018] As shown in Figure 4, if the length of one side of the open surface 17a of the first storage section 11 in the adjacent direction is A, the length of one side of the open surface 17b of the second storage section 12 in the adjacent direction is B, and the depth of the first storage section 11 and the second storage section 12 (the vertical distance between the open surfaces 17a and 17b and the bottom surfaces 15a and 15b) is D, then it is preferable that the conditions A > D and B > D are satisfied. As will be described in detail later, if the depth D is greater than or equal to length A or B, the overlap of the sheet material 1 at the bottom surfaces 15a and 15b of the first storage section 11 or the second storage section 12 will disappear, and the strength of the packaging container 100 will decrease. In addition, since increasing the overlapping area of ​​the sheet material 1 at the bottom surfaces of the first storage section 11 and the second storage section 12 increases the strength of the bottom surfaces 15a and 15b, it is preferable that lengths A and B are sufficiently long relative to the depth D.

[0019] The flange portion 14 is a rectangular annular portion that extends outward from the periphery of the open surfaces 17a and 17b of the first housing portion 11 and the second housing portion 12, and surrounds the first housing portion 11, the second housing portion 12, and the connecting piece 13. The outer surface of the flange portion 14 (the upper surface in Figure 1) is made flat. If the outer surface of the flange portion 14 is not flat, the pressure when sealing the lid material, etc., to the outer surface of the flange portion 14 of the packaging container 100 will be uneven, resulting in uneven welding and making it difficult to ensure airtightness.

[0020] In the flange portion 14, the sheet material 1 is folded back towards the bottom portions 15a and 15b along the four sides of the outer edge of the rectangular flange portion 14. In other words, the sheet material 1 is double-layered on all four sides of the flange portion 14. This increases the rigidity of the flange portion 14, preventing the packaging container 100 from deforming during use due to the weight of its contents.

[0021] The sheet material 1 is preferably a paper-based material. For example, the base material of the sheet material 1 may have a basis weight of 100 to 500 g / m². 2 Paperboard can be used. The basis weight of the paperboard used as the base material should be 190-400 g / m². 2 If so, it is more preferable because it has excellent processability. The sheet material 1 may have one or more layers as needed, such as a resin film, a barrier layer, a sealant layer, a paper protective layer, an ink layer (printing layer), or an overcoat varnish layer. However, in order to reduce the amount of resin used, it is preferable that the proportion of paper in the sheet material is 50% by mass or more. Of the two sides of the sheet material 1, it is preferable to use a material that has welding properties to the liner material 3 on the side to which the liner material 2 described later is sealed.

[0022] The liner material 2 is made of a resin film and seals to the inner surfaces (inside of the box shape) of the first housing section 11 and the second housing section 12, the upper surface of the connecting piece 13, and the outer surface of the flange section 14. The liner material 2 integrates each surface constituting the first housing section 11 and the second housing section 12, the connecting piece 13, and the flange section 14, and plays a role in providing strength to the entire packaging container 100. The material of the liner material 2 is not particularly limited, but a thermoplastic resin film having water resistance, airtightness, pinhole resistance, and heat sealability can be suitably used. Furthermore, the liner material 2 may be a single-layer film, a laminated film in which multiple resin layers are laminated by extrusion, or a laminated film laminated via an adhesive layer. Examples of thermoplastic resins that can be used for liner material 2 include polyethylene (PE), polypropylene (PP), nylon (NY), polyamide, polyester, ethylene-vinyl acetate copolymer (EVOH), ethylene-acrylic acid copolymer, polyvinyl alcohol, ethylene-vinyl alcohol copolymer, polybutene, polyvinylidene chloride, and polystyrene. For example, as liner material 2, a polyethylene-based barrier multilayer film having a layer structure of PE (20 μm) / adhesive layer / EVOH (10 μm) adhesive layer / PE (20 μm) or a polypropylene-based barrier multilayer film having a layer structure of CPP (unoriented polyethylene, 20 μm) / adhesive layer / EVOH / adhesive layer / CPP can be used.

[0023] The method of sealing the liner material 2 to the sheet material 1 is not particularly limited. However, it is preferable that the liner material 2 is peelable from the sheet material 1. When the liner material 2 is peelable from the main body 10, for example, the liner material 2 may be sealed to the entire outer surface of the flange portion 14, while only partially sealing to the inner surfaces of the first and second housing portions 11 and 12, and to the connecting pieces 13. Alternatively, the liner material 2 may be made peelable by sealing it to the sheet material 1 via a release varnish layer or an easy-peel sealant film. When the liner material 2 is peelable from the sheet material 1, the sheet material 1, which is mainly paper, can be recycled by separating the two, and the liner material 2, which is a resin film, is also easy to dispose of. In addition, a lid or the like may be sealed to the outer surface of the flange portion 14 of the packaging container 100. In this case, the seal strength between the lid or the like and the liner material 2 is adjusted to be less than the seal strength between the liner material 2 and the sheet material 1.

[0024] Figure 5 is an unfolded view of the blank material used in the manufacture of the packaging container shown in Figure 1.

[0025] The blank material 110 comprises a ring portion 104, a connecting panel 113, a pair of first reinforcing panels 114a and 114b, a pair of second reinforcing panels 124a and 124b, a pair of first side panels 116a and 116b, a pair of second side panels 126a and 126b, a pair of third side panels 136a and 136b, a pair of fourth side panels 146a and 146b, a pair of first bottom panels 115a and 115b, a pair of second bottom panels 125a and 125b, and a pair of third bottom panels 135a and 135b. Each of the above-mentioned parts is integrally constructed from the same sheet material.

[0026] The ring portion 104 has a rectangular annular shape. The ring portion 104 is the part that constitutes the outer surface of the flange portion 14 shown in Figure 1. The outer periphery of the ring portion 104 is rectangular and has a pair of opposing first sides 101a and 101b, and a pair of adjacent and opposing second sides 102a and 102b. In Figure 5, the long sides of the ring portion 104 are shown as the first sides 101a and 101b, and the short sides as the second sides 102a and 102b. The inner periphery of the ring portion 104 is also rectangular and has a pair of third sides 103a and 103b parallel to the first sides 101a and 101b of the outer periphery, and a pair of adjacent and opposing fourth sides 104a and 104b.

[0027] The connecting panel 113 is a strip-shaped portion that constitutes the connecting piece 13 shown in Figure 1. The connecting panel 113 connects a pair of opposing fourth sides 103a and 103b on the inner periphery of the ring portion 104, dividing the inside of the ring portion 104 into a rectangular first region 117a and an adjacent rectangular second region 117b. The first region 117a corresponds to the area inside the open surface 17a shown in Figure 1, and the second region 117b corresponds to the area inside the open surface 17b.

[0028] Each of the pair of first reinforcing panels 114a, 114b and the pair of second reinforcing panels 124a, 124b corresponds to the folded flange portion 14 (the lower surface portion of the flange portion 14) and is connected to the four sides of the outer edge of the ring portion 104. Specifically, the first reinforcing panel 114a is connected to the first side 101a, the first reinforcing panel 114b is connected to the first side 101b, the second reinforcing panel 124a is connected to the second side 102a, and the second reinforcing panel 124b is connected to the second side 102b. Each of the pair of first reinforcing panels 114a, 114b and the pair of second reinforcing panels 124a, 124b is bonded to the back surface of the ring portion 104 with an adhesive or the like when assembling the blank material 110. This makes it possible to form a flange portion 14 in which the sheet material 1 is double-layered, thereby increasing the strength of the flange portion 14.

[0029] Each of the first to fourth side panels corresponds to a side portion of the packaging container 100 shown in Figure 1. Preferably, the height H of each side panel (the vertical distance between the connection point of the reinforcing panel and the connection point of the bottom panel on each side panel) is equal.

[0030] A pair of first side panels 116a, 116b and a pair of second side panels 126a, 126b are connected to a pair of first reinforcing panels 114a, 114b, respectively, corresponding to the first region 117a and the second region 117b, and to parts of the side portions of adjacent first and second housing sections 11 and 12. Specifically, the first side panel 116a is connected to the portion of the first reinforcing panel 114a corresponding to the first region 117a and constitutes the side portion 16a of the first housing section 11. The first side panel 116b is connected to the portion of the first reinforcing panel 114b corresponding to the first region 117a and constitutes the side portion 16b of the first housing section 11. The second side panel 126a is connected to the portion of the first reinforcing panel 114a corresponding to the second region 117b and constitutes the side portion 16e of the second housing section 12. The second side panel 126b is connected to the portion of the first reinforcing panel 114b that corresponds to the second area 117b, and constitutes the side portion 16f of the second housing section 12.

[0031] The pair of third side panels 136a and 136b are connected to the second reinforcing panels 124a and 124b, respectively, and correspond to parts of the side portions of the first and second housing sections 11 and 12. Specifically, the third side panel 136a is connected to the second reinforcing panel 124a and constitutes the side portion 16c of the first housing section 11. The third side panel 136b is connected to the second reinforcing panel 124b and constitutes the side portion 16g of the second housing section 12.

[0032] The pair of fourth side panels 146a and 146b are connected to the connecting panel 113 within the first region 117a and the second region 117b, and correspond to parts of the side portions of the first housing section 11 and the second housing section 12. Specifically, the fourth side panel 146a is connected to the connecting panel 113 within the first region 117a and constitutes the side portion 16d of the first housing section 11. The fourth side panel 146b is connected to the connecting panel 113 within the second region 117b and constitutes the side portion 16g of the second housing section 12.

[0033] The side panels located on the first region 117a side (first side panels 116a and 116b, third side panel 136a, and fourth side panel 146a) constitute the four side sections 16a to 16d of the first housing section 11. In addition, the side panels located on the second region 117b side (second side panels 126a and 126b, third side panel 136b, and fourth side panel 146b) constitute the four side sections 16e to 16h of the second housing section 12.

[0034] A pair of first bottom panels 115a and 115b are connected to a pair of first side panels 116a and 116b, respectively, and constitute a part of the bottom surface 15a of the first storage section 11. A pair of second bottom panels 125a and 125b are connected to a pair of second side panels 126a and 126b, respectively, and constitute a part of the bottom surface 15b of the second storage section 12. A pair of third bottom panels 135a and 135b are connected to a pair of third side panels 136a and 136b, respectively, and constitute a part of the bottom surface 15a of the first storage section 11 and a part of the bottom surface 15b of the second storage section 12. A pair of fourth bottom panels 145a and 145b are connected to a pair of fourth side panels 146a and 146b, respectively, and constitute a part of the bottom surface 15a of the first storage section 11 and a part of the bottom surface 15b of the second storage section 12.

[0035] The bottom surface 15a of the first storage section 11 is formed by the bottom panels located on the first region 117a side (first bottom panels 115a and 115b, third bottom panel 135a, and fourth bottom panel 145a). The bottom surface 15b of the second storage section 12 is formed by the side panels located on the second region 117b side (second bottom panels 125a and 125b, third bottom panel 135b, and fourth bottom panel 145b).

[0036] The length A' of the third sides 103a and 103b of the ring portion 104 constituting the first region 117a is the length A described above, and the length B' of the third sides 103a and 103b of the ring portion 104 constituting the second region 117b is the length B described above. In other words, the width of the open surfaces 17a and 17b of the first and second storage portions 11 and 12, and the capacity of the first and second storage portions 11 and 12 can be adjusted by the formation position of the connecting panel 113 on the third sides 103a and 103b of the ring portion 104.

[0037] Furthermore, the depth D of the first storage section 11 and the second storage section 12 is determined by the height H of each side panel. Therefore, if the packaging container 100 is to be a deep container, the height H of all side panels should be increased. However, in this embodiment, the fourth side panels 146a and 146b connected to the connecting panel 113 are formed inside the ring section 104, and furthermore, the fourth bottom panels 145a and 145b must also be formed inside the ring section 104. Therefore, the height H of the side panels is smaller than the length A' of the third sides 103a and 103b of the ring section 104 constituting the first region 117a, and the length B' of the third sides 103a and 103b of the ring section 104 constituting the second region 117b (A'>H and B'>H). In this embodiment, the blank material 110 is formed by punching out a single sheet material. Therefore, when A'=H or B'=H, the fourth bottom panels 145a and 145b cannot be formed, resulting in no overlap of the sheet material 1 at the bottom portions 15a and 15b of the first storage section 11 or the second storage section 12, and a decrease in the strength of the packaging container 100.

[0038] As described above, in this embodiment, since reinforcing panels are connected to each of the four sides of the outer edge of the ring portion 104, when the blank material 110 is assembled as a packaging container 100, the flange portion 14 can be formed by overlapping the sheet material 1 in two layers. As a result, the strength of the flange portion 14 is increased, and deformation of the packaging container 100 during use can be suppressed.

[0039] Furthermore, a connecting panel 113 is formed on the inner periphery of the ring portion 104, connecting a pair of opposing first sides 101a and 101b. From one edge of the connecting panel 113, a fourth side panel 146a and a fourth bottom panel 145a, which become part of the first storage portion 11 of the packaging container 100, are connected. From the other edge of the connecting panel 113, a fourth side panel 146b and a fourth bottom panel 145b, which become part of the second storage portion 12 of the packaging container 100, are connected. Therefore, a packaging container 100 with a first storage portion 11 and a second storage portion 12 separated can be constructed from a single blank material 110.

[0040] Furthermore, all side panels other than the pair of fourth side panels 146a and 146b are formed on the outside of the ring portion 104. Therefore, compared to the case where all of the four side panels constituting the storage portion are formed on the inside of the ring portion 104 (see Figure 16), the height H of the side panels can be increased, and a deep packaging container 100 (with a deep depth D) can be made.

[0041] (Variation 1) A modification 1 of this embodiment will now be described. Figure 6 is a perspective view from below of the packaging container according to modification 1 of the first embodiment, and Figure 7 is a front view of the packaging container shown in Figure 6.

[0042] The packaging container 200 according to Modified Example 1 is provided with a pair of center ribs 18 located along the lower surface of the flange portion 14, connecting the side surfaces of adjacent first and second storage portions 11 and 12. Specifically, one center rib 18 connects side surfaces 16a and 16e, and the other center rib 18 connects side surfaces 16b and 16f. Furthermore, each of the center ribs 18 forms the same plane as the side surfaces of adjacent first and second storage portions 11 and 12.

[0043] The presence of the center rib 18 creates a gap between the stacked flange portions 14 when multiple packaging containers 100 are stacked, equal to the height of the center rib 18. This makes it easier to remove each packaging container 200 individually, facilitating handling in filling machines and the like. Furthermore, the strength between the first storage portion 11 and the second storage portion 12 is increased, preventing the packaging container 100 from breaking between the first and second storage portions 12 due to the weight of the contents. If the contents are heavy and it is desired to increase the strength between the first and second storage portions 11 and the second storage portion 12, the height h1 of the center rib 18 can be set higher (Figure 7). On the other hand, since the transport efficiency of the stacked packaging containers 200 decreases depending on the height of the center rib 18, it is preferable that the height h1 of the center rib 18 be 15 mm or less. The height of the center rib 18 is defined as the distance from the bottom surface of the flange portion 14 in the direction along the side portion (side portions 16a, 16b, 16e, 16f) to which the center rib 18 is connected.

[0044] Figure 8 is an unfolded view of the blank material used in the manufacture of the packaging container shown in Figure 6.

[0045] In the blank material according to Modified Example 1, center rib panels 118a and 118b corresponding to each of the pair of center ribs 18 of the packaging container 200 are formed. The center rib panels 118a and 118b connect adjacent first side panels 116a, 116b and second side panels 126a, 126b and first reinforcing panels 114a, 114b, respectively. Specifically, the center rib panel 118a connects adjacent first side panels 116a and second side panels 126a to the first reinforcing panel 114a, and the center rib panel 118b connects adjacent first side panels 116b and second side panels 126b to the first reinforcing panel 114b. By making the length L1 from the outer edge of the ring portion 104 of the center rib panels 118a and 118b to the end opposite to it 15 mm or less, the height of the center rib 18 can be made 15 mm or less.

[0046] (Modification 2) A second modification of this embodiment will now be described. Figure 9 is a perspective view from below of the packaging container according to the second modification of the first embodiment, and Figure 10 is a front view of the packaging container shown in Figure 9.

[0047] The packaging container 300 according to the modified example 2 is provided with four corner ribs 19 at locations corresponding to the four corners of the ring portion 104. The corner ribs 19 are formed to extend outward from the respective side surfaces of the first housing portion 11 and the second housing portion 12, at the four corners of the flange portion 14 and along the lower surface of the flange portion 14.

[0048] The presence of corner ribs 19 creates a gap between the stacked flange portions 14 when multiple packaging containers 300 are stacked, equal to the height of the corner ribs 19. This makes it easier to remove each packaging container 300 individually, facilitating handling in filling machines and the like. This effect can also be obtained by providing the center rib 18 described in Modification 1. However, if only the center rib 18 is provided, when multiple packaging containers are stacked, the packaging containers 100 may deform into a fan shape with the center rib 18 and connecting piece 13 as fulcrums, potentially leading to an imbalance in the stacked packaging containers. Therefore, by further providing corner ribs 19 at the four corners of the packaging container, it is possible to suppress the fan-shaped deformation even when the packaging containers 300 are stacked high. The height h2 of the corner rib 19 can be the same as the height of the center rib 18, and is preferably 15 mm or less. The height of the corner rib 19 is the distance from the bottom surface of the flange portion 14 in the direction along the side portion to which the corner rib 19 is connected. Furthermore, it is preferable that each of the corner ribs 19 forms the same plane as the side surface of the first housing portion 11 or the second housing portion 12, and does not protrude outward from the flange portion 14 in a plan view (Figure 10).

[0049] Figure 11 is an unfolded view of the blank material used in the manufacture of the packaging container shown in Figure 9.

[0050] In the blank material according to the modified example 2, a corner rib panel 119 corresponding to each corner rib 19 is formed. Each corner rib panel 119 is formed along the first side panels 116a, 116b and the second side panels 126a, 126b to which the corner rib panel 119 is connected, from the connection between the first reinforcing panels 114a and 114b and the first side panels 116a and 116b, and from the connection between the first reinforcing panels 114a and 114b and the second side panels 126a, 126b, at the ends of the pair of first side panels 116a, 116b and the pair of second side panels 126a, 126b on the third side panel 136a and 136b side, respectively. Furthermore, by making the length L2 of each of the four corner rib panels 119 15 mm or less, the height h2 of the corner rib 19 can be made 15 mm or less. The length of the corner rib panel 119 is the length along the side panel on which the corner rib panel 119 is formed. Furthermore, by making the amount L3 protruding from the end of the side panel on which the corner rib panel 119 is formed less than or equal to the width of the ring portion 104, the corner rib 19 can be prevented from protruding outward from the flange portion 14 in a plan view.

[0051] Furthermore, as shown in Figure 12, the corner rib panel 119 may be formed at each end of the pair of third side panels 136a and 136b, extending from the connection between the second reinforcing panels 124a and 124b and the third side panels 136a and 136b, along the third side panel 136a to which the corner rib panel 119 is connected. In this case, the four corner ribs 19 are formed to protrude from the width direction of the side portions (side portions 16c and 16g) which are the shorter sides in Figure 9.

[0052] (Second embodiment) Figure 13 is a perspective view of the packaging container according to the second embodiment, and Figure 14 is a cross-sectional view along the BB line shown in Figure 13. The packaging container 400 according to the second embodiment differs from the packaging container according to the first embodiment in that it does not have a structure corresponding to a partition. The differences from the first embodiment will be described in detail below.

[0053] The packaging container 400 comprises a sheet material 1 and a liner material 2. The sheet material 1 is a sheet that serves as the base material for the packaging container 400 and constitutes the main body portion 40. The main body portion 40 is made of a single sheet material 1 and has a box-shaped housing portion 41 with an open surface and a flange portion 414 surrounding the housing portion 411. The liner material 2 seals the inner surface of the housing portion 411 (the inside of the box shape) and the outer surface of the flange portion 414. The liner material 2 integrates each surface constituting the housing portion 411 with the flange portion 414 and plays a role in providing strength to the entire packaging container 400.

[0054] The storage section 411 has a rectangular shape in plan view and includes a bottom surface 415, four side surfaces 416a to 416d, and a rectangular open surface 417.

[0055] The flange portion 414 is a rectangular, annular portion that extends outward from the periphery of the open surface 417 of the housing portion 411 and surrounds the housing portion 411. The outer surface of the flange portion 414 is flat. If the outer surface of the flange portion 414 is not flat, the pressure will be uneven when sealing a lid or the like to the outer surface of the flange portion 414 of the packaging container 400, resulting in uneven welding and making it difficult to ensure airtightness.

[0056] In the flange portion 414, the sheet material 1 is folded back towards the bottom portion 415 along the four sides of the outer edge of the rectangular flange portion 414. In other words, the sheet material 1 is double-layered on all four sides of the flange portion 414. This increases the rigidity of the flange portion 414, preventing the packaging container 400 from deforming during use due to the weight of its contents.

[0057] Figure 15 is an unfolded view of the blank material used in the manufacture of the packaging container shown in Figure 13.

[0058] The blank material 510 comprises a ring portion 504, a pair of first reinforcing panels 514a and 514b, a pair of second reinforcing panels 524a and 524b, a pair of first side panels 516a and 516b, a pair of second side panels 526a and 526b, a pair of first bottom panels 515a and 515b, and a pair of second bottom panels 525a and 525b. Each of the above-mentioned parts is integrally constructed from the same sheet material.

[0059] The ring portion 504 has a rectangular annular shape. The ring portion 504 is a part that constitutes the outer surface of the flange portion 414. The outer edge of the ring portion 504 is rectangular and has a pair of opposing first sides 501a and 501b, and a pair of adjacent and opposing second sides 502a and 502b.

[0060] Each of the pair of first reinforcing panels 514a and 514b and the pair of second reinforcing panels 524a and 524b corresponds to the folded flange portion 514 (the lower surface portion of the flange portion 414) and is connected to the four sides of the outer edge of the ring portion 504. Specifically, the first reinforcing panel 514a is connected to the first side 501a, the first reinforcing panel 514b is connected to the first side 501b, the second reinforcing panel 524a is connected to the second side 502a, and the second reinforcing panel 524b is connected to the second side 502b. Each of the pair of first reinforcing panels 514a and 514b and the pair of second reinforcing panels 524a and 524b is bonded to the back surface of the ring portion 504 with an adhesive or the like when assembling the blank material 510. This makes it possible to form a flange portion 514 which is composed of two layers of sheet material 1.

[0061] Each of the first and second side panels corresponds to a part of the side of the packaging container 400 shown in Figure 13. The pair of first side panels 516a and 516b are connected to the first reinforcing panels 514a and 514b, respectively, and correspond to a part of the side of the storage section 411. Specifically, the first side panel 516a is connected to the first reinforcing panel 514a and constitutes the side 416a of the storage section 411. The first side panel 516b is connected to the first reinforcing panel 514b and constitutes the side 416b of the storage section 411. The pair of second side panels 526a and 526b are connected to the second reinforcing panels 524a and 524b, respectively, and correspond to another part of the side of the storage section 411. Specifically, the second side panel 526a is connected to the second reinforcing panel 524a and constitutes the side 416c of the storage section 411. The second side panel 526b is connected to the second reinforcing panel 524b and constitutes the side portion 416d of the housing 411.

[0062] A pair of first bottom panels 515a and 515b are connected to a pair of first side panels 516a and 516b, respectively, and constitute a part of the bottom portion 415 of the storage section 411. A pair of second bottom panels 525a and 525b are connected to a pair of second side panels 526a and 526b, respectively, and constitute another part of the bottom portion 415 of the storage section 411. In other words, the pair of first bottom panels 515a and 515b and the pair of second bottom panels 525a and 525b constitute the bottom portion 415 of the packaging container 400.

[0063] In this embodiment as well, similar to Modification 2 of the first embodiment, four corner ribs (not shown) may be provided at the four corners of the flange portion 414. The corner ribs are formed so as to extend outward from each side surface of the housing portion 411 at the four corners of the flange portion 414 and along the lower surface of the flange portion 414. When multiple packaging containers 400 are stacked, the height of the corner ribs creates a gap between the stacked flange portions 414. This makes it easier to pick up each packaging container 400 one by one, and facilitates handling in filling machines, etc. Furthermore, since the transport efficiency of the stacked packaging containers 400 decreases, it is preferable that the height of the corner ribs be 15 mm or less. Here, the height of the corner rib is the distance from the lower surface of the flange portion 414 in the direction along the side surface to which the corner rib is connected. Furthermore, it is preferable that each corner rib forms the same plane as the side surface of the housing portion 411 and does not protrude outward from the flange portion 414 in a plan view.

[0064] As described above, in this embodiment as well, similar to the packaging container 100 according to the first embodiment, reinforcing panels are connected to each of the four sides of the outer edge of the ring portion 504. Therefore, when assembling the blank material 510, the flange portion 414 can be formed by overlapping the sheet material 1 in two layers. As a result, the strength of the flange portion 414 is increased, and deformation of the packaging container 400 during use can be suppressed.

[0065] Furthermore, the pair of first side panels 516a, 516b and the pair of second side panels 526a, 526b are all formed on the outside of the ring portion 504. Therefore, compared to the case where the side panels constituting the storage portion 411 are formed on the inside of the ring portion 504, the side panels can be made higher, and a deep packaging container 400 can be made. [Examples]

[0066] (Example 1) A packaging container having a first storage section and a second storage section was manufactured as shown in Figure 1. The outer dimensions of the flange section were set to 127 mm × 178 mm, with the width of the flange section parallel to the connecting piece being 9.5 mm, the width of the flange section perpendicular to the connecting piece being 10 mm, and the width of the connecting piece being 10 mm. Furthermore, the lengths A and B were set to 74.5 mm, and the depth D was set to 33.8 mm. In addition, the basis weight of the paper used for the sheet material constituting the packaging container was set to 310 g / m². 2 That's what I decided.

[0067] (Example 2) A packaging container was manufactured in the same manner as in Example 1, except that a center rib with a height of 5 mm was formed.

[0068] (Example 3) A packaging container was manufactured in the same manner as in Example 1, except that a center rib with a height of 8 mm was formed.

[0069] (Example 4) A packaging container was manufactured in the same manner as in Example 1, except that a center rib with a height of 11 mm was formed.

[0070] The packaging containers according to Examples 1 to 4 were positioned with the open side facing downwards, and the first storage section was fixed in place. A string was attached to the center of the bottom surface of the second storage section, and the string was pulled upward using a tensile testing machine until a bend occurred between the first and second storage sections. The maximum strength at which no bend occurred (the load-bearing capacity of the packaging container) was measured.

[0071] The stability of the packaging containers according to Examples 1 to 4 was investigated by stacking multiple containers. Specifically, a circle (○) was used to indicate that no tilting occurred when stacking multiple packaging containers, and a triangle (△) was used to indicate that tilting occurred.

[0072] Table 1 shows the evaluation results for the length of the center rib of the packaging container, the load-bearing capacity of the packaging container, and the stability of the packaging container for Examples 1 to 4.

[0073] [Table 1]

[0074] The evaluation results from Examples 1-4 clearly showed that the longer the center rib, the greater the load-bearing capacity of the packaging container. On the other hand, if the center rib was too long, the overlapping area of ​​the sides of the stacked packaging containers decreased, resulting in poor stability. [Industrial applicability]

[0075] This invention can be applied to packaging containers for packaging food and other articles. [Explanation of Symbols]

[0076] 1: Sheet material 2: Liner material 3: Liner material 10: Main body 11: First Detention Unit 12: Second containment unit 13: Connecting piece 14: Flange section 15a, 15b: Bottom part 16a~16h: Side part 17a, 17b: Open surface 18: Center Rib 19: Corner Rib 40: Main body 41: Containment Unit 101a, 101b: First side 102a, 102b: Second side 104: Ring section 110: Blank material 113: Connection Panel 114: Flange section 114a, 114b: First reinforcement panel 115a, 115b: First bottom panel 116a, 116b: First side panel 117 :Open surface 117a: 1st area 117b:Second area 118a, 118b: Center rib panel 119: Corner Rib Panel 124a, 124b: Second reinforcement panel 125a, 125b: Second bottom panel 126a, 126b: Second side panel 135a, 135b: Third bottom panel 136a, 136b: Third side panel 145a, 145b: Fourth bottom panel 146a, 146b: Fourth side panel 411: Containment Unit 414: Flange section 415: Bottom part 416a~416d: Side part 417 :Open surface 501a, 501b: First side 502a, 502b: Second side 504: Ring section 510: Blank material 514: Flange section 514a, 514b: First reinforcement panel 515a, 515b: First bottom panel 516a, 516b: First side panel 524a, 524b: Second reinforcement panel 525a, 525b: Second bottom panel 526a, 526b: Second side panel D: Depth H: Height L3:Protrusion amount h1: height h2: height 100, 200, 400, 4000: Packaging container

Claims

1. A packaging container, A box-shaped first and second housing section having a bottom surface, four side surfaces, and a rectangular open surface; a strip-shaped connecting piece connecting one side of the open surface of the first housing section and one side of the open surface of the second housing section; and a rectangular, annular, flat flange section extending outward from the periphery of the open surfaces of the first and second housing sections, surrounding the first housing section, the second housing section, and the connecting piece; The liner material is provided to seal the inner surfaces of the first housing and the second housing, and the outer surfaces of the connecting piece and the flange portion. The main body is made of a single sheet material, A packaging container characterized in that the sheet material is folded back along the four sides of the flange portion and is double-layered at the flange portion.

2. The packaging container according to claim 1, wherein A is the length of one side of the open surface of the first storage section in the adjacent direction to the first storage section, B is the length of one side of the open surface of the second storage section in the adjacent direction, and D is the depth of the first storage section and the second storage section, and the conditions A > D and B > D are satisfied.

3. A pair of center ribs are provided at a position along the lower surface of the flange portion, connecting the side portions of the adjacent first and second housing portions. Each of the center ribs is on the same plane as the adjacent side surfaces of the first and second housing sections. The packaging container according to claim 1, wherein, in the direction along the side portion to which the center rib is connected, the height of each of the center ribs from the lower surface of the flange portion is 15 mm or less.

4. Four corner ribs are provided at the four corners of the flange portion and along the lower surface of the flange portion, extending outward from the respective side surfaces of the first and second housing portions. Each of the corner ribs forms the same plane as the side surface of the first or second housing portion, and does not protrude outward from the flange portion in a plan view. The packaging container according to claim 1, wherein, in the direction along the side portion to which the corner ribs are connected, the height of each corner rib from the lower surface of the flange portion is 15 mm or less.

5. A pair of center ribs are provided at a position along the lower surface of the flange portion, connecting the side portions of the adjacent first and second housing portions. Each of the center ribs is on the same plane as the adjacent side surfaces of the first and second housing sections. In the direction along the side portion to which the center rib is connected, the height of each of the center ribs from the lower surface of the flange portion is 15 mm or less. Four corner ribs are provided at the four corners of the flange portion and along the lower surface of the flange portion, extending outward from the respective side surfaces of the first and second housing portions. Each of the corner ribs forms the same plane as the side surface of the first or second housing portion, and does not protrude outward from the flange portion in a plan view. The packaging container according to claim 1, wherein, in the direction along the side portion to which the corner ribs are connected, the height of each corner rib from the lower surface of the flange portion is 15 mm or less.

6. A blank material used in the manufacture of the packaging container described in claim 1, A ring portion having a rectangular annular shape corresponding to the outer surface of the flange portion, A connecting panel corresponding to the connecting piece connects a pair of opposing sides on the inner periphery of the ring portion, dividing the inside of the ring portion into a rectangular first region and an adjacent rectangular second region, A pair of first reinforcing panels are connected to each of the four sides of the outer periphery of the ring portion, which are parallel to the adjacent directions of the first region and the second region, and which correspond to a part of the folded flange portion. A pair of second reinforcing panels are connected to each of the four sides of the outer periphery of the ring portion, which are adjacent to the first side, and which correspond to the other part of the folded flange portion. Each of the first reinforcing panels is connected to a pair of first side panels and a pair of second side panels, which are provided corresponding to the first and second regions and to the adjacent side surfaces of the first and second housing sections. A pair of third side panels are connected to each of the second reinforcing panels and correspond to a portion of the side surfaces of the first and second housings, A pair of fourth side panels are connected to the connecting panel within the first and second regions and correspond to a portion of the side surfaces of the first and second housing sections, A pair of first bottom panels are connected to each of the pair of first side panels and correspond to a part of the bottom surface of the first housing, A pair of second bottom panels are connected to each of the pair of second side panels and correspond to a part of the bottom surface of the second housing, A pair of third bottom panels are connected to each of the pair of side panels, and the third bottom panels correspond to a portion of the bottom of the first housing and a portion of the bottom of the second housing. A blank material comprising a pair of fourth bottom panels connected to each of the pair of fourth side panels, and corresponding to a portion of the bottom of the first housing and a portion of the bottom of the second housing.

7. It comprises a pair of center rib panels connecting the adjacent first and second side panels and the first reinforcing panel, The blank material according to claim 6, wherein the length of the center rib panel from the outer peripheral edge of the first reinforcing panel to the end of the center rib panel opposite to the outer peripheral edge of the ring portion is 15 mm or less.

8. The ring portion is further provided with four corner rib panels located at the four corners of the ring portion, Each of the four aforementioned corner rib panels is, At each end of the pair of third side panels, the corner rib panel is formed along the third side panel to which it is connected, extending from the connection between the second reinforcing panel and the third side panel, or At the end of each of the pair of first side panels and the pair of second side panels on the third side panel side, the corner rib panel is formed along the first and second side panels to which it is connected, extending from the connection portion between the first reinforcing panel and the first side panel, and from the connection portion between the first reinforcing panel and the second side panel. Each of the four aforementioned corner rib panels is, The length along the side panel on which the corner rib panel is formed is 15 mm or less. The blank material according to claim 6, wherein the amount of protrusion from the end of the side panel on which the corner rib panel is formed is less than or equal to the width of the ring portion.

9. It comprises a pair of center rib panels connecting the adjacent first and second side panels and the first reinforcing panel, The length of the center rib panel from the outer peripheral edge of the first reinforcing panel to the end of the center rib panel opposite to the outer peripheral edge of the ring portion is 15 mm or less. The ring portion is further provided with four corner rib panels located at the four corners of the ring portion, Each of the four aforementioned corner rib panels is, At each end of the pair of third side panels, the corner rib panel is formed along the third side panel to which it is connected, extending from the connection between the second reinforcing panel and the third side panel, or At the end of each of the pair of first side panels and the pair of second side panels on the third side panel side, the corner rib panel is formed along the first and second side panels to which it is connected, extending from the connection portion between the first reinforcing panel and the first side panel, and from the connection portion between the first reinforcing panel and the second side panel. Each of the four aforementioned corner rib panels is, The length along the side panel on which the corner rib panel is formed is 15 mm or less. The blank material according to claim 6, wherein the amount of protrusion from the end of the side panel on which the corner rib panel is formed is less than or equal to the width of the ring portion.

10. A packaging container, A box-shaped housing having a bottom, side, and rectangular open surface, and a main body having a rectangular annular flat flange portion extending outward from the periphery of the open surface and surrounding the housing, The housing portion is provided with a liner material that seals the inner surface and the outer surface of the flange portion, The main body is made of a single sheet material, A packaging container characterized in that the sheet material is folded back along the four sides of the flange portion and is double-layered at the flange portion.

11. Corner ribs are provided at the four corners of the flange portion and along the lower surface of the flange portion, extending outward from each of the side portions of the housing portion. Each of the corner ribs forms the same plane as the side surface of the housing portion and does not protrude outward from the flange portion in a plan view. The packaging container according to claim 10, wherein, in the direction along the side portion to which the corner ribs are connected, the height of each corner rib from the lower surface of the flange portion is 15 mm or less.

12. A blank material used in the manufacture of the packaging container described in claim 10, A ring portion having a rectangular annular shape corresponding to the flange portion, A pair of first reinforcing panels are connected to each of the four sides of the outer edge of the ring portion, and the first reinforcing panels correspond to a part of the folded flange portion. A pair of second reinforcing panels are connected to each of the four sides of the outer periphery of the ring portion, which are adjacent to the first side, and which correspond to the other part of the folded flange portion. A pair of first side panels are connected to each of the first reinforcing panels and correspond to a part of the side surface of the housing section, A pair of second side panels connected to each of the second reinforcing panels and corresponding to other parts of the side of the housing section, A first bottom panel is connected to each of the pair of first side panels and corresponds to a part of the bottom surface of the housing section, A blank material comprising a pair of second bottom panels connected to each of the pair of second side panels and corresponding to other parts of the bottom of the housing.

13. It also features four corner rib panels, Each of the four aforementioned corner rib panels is, At each of the two ends of the pair of first side panels, the corner rib panel is formed along the first side panel to which it is connected, extending from the connection between the first reinforcing panel and the first side panel, or At each end of the pair of the second side panels, the corner rib panel is formed along the second side panel to which it is connected, from the connection between the second reinforcing panel and the second side panel. Each of the four aforementioned corner rib panels is, The length along the side panel on which the corner rib panel is formed is 15 mm or less. The blank material according to claim 12, wherein the amount of protrusion from the end of the side panel on which the corner rib panel is formed is less than or equal to the width of the ring portion.

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