Container

Abstract

To provide a container having high shape retention.SOLUTION: A container according to one embodiment comprises a bottom wall part, a side wall part including a plurality of side wall pieces erected from an outer edge of the bottom wall part, which defines a storage space together with the bottom wall part, and a flange part including a plurality of flange pieces expanding from upper ends of the plurality of side wall pieces to the outside. The bottom wall part has partitions partitioning the storage space into a plurality of small spaces. At least either of a pair of adjacent side wall pieces of the plurality of side wall pieces and a pair of adjacent flange pieces of the plurality of flange pieces are joined to each other so as to partially overlap with each other from a thickness direction.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] SUMMARY The present disclosure relates to containers formed by folding a blank sheet having a paper substrate. [Background technology]

[0002] Conventionally, paper containers for containing contents such as food have been widely used. For example, Patent Document 1 discloses a film-covered tray formed by folding a blank sheet of paper and having its inner surface covered with a film. This tray includes a container body having a bottom wall and a plurality of side walls defining a large storage space therein, and a partition dividing the large storage space into two or more small storage spaces. The edges of a pair of adjacent side walls of the container body are butted against each other and are held upright against the bottom wall by a film that straddles the edges of the pair of side walls. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2023-007887 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the above-mentioned film-attached tray, the edges of a pair of side walls are butted against each other, and the shape is maintained by the film that straddles the edges of the pair of side walls, so that a locally low-rigidity area where no paper base material is disposed is formed at the boundary between the edges of the pair of side walls. Therefore, this tray is easily folded from the boundary, and the container has difficulty in retaining its shape. If the container has poor shape retention, it cannot maintain its shape when lifted with contents inside, and the contents may spill out.

[0005] Therefore, an object of the present disclosure is to provide a container having high shape retention. [Means for solving the problem]

[0006] A container according to one embodiment is formed by folding a blank sheet having a paper base material, the container comprising a bottom wall portion, a plurality of side wall pieces erected from an outer edge of the bottom wall portion to define a storage space together with the bottom wall portion, and a flange portion including a plurality of flange pieces extending outward from upper ends of the plurality of side wall pieces, the bottom wall portion having a partition dividing the storage space into a plurality of small spaces, and at least one of a pair of adjacent side wall pieces among the plurality of side wall pieces and a pair of adjacent flange pieces among the plurality of flange pieces are joined to each other in a partially overlapping state in the thickness direction.

[0007] In the container according to the above aspect, a pair of adjacent side wall pieces or a pair of adjacent flanges are joined to each other in a partially overlapping state in the thickness direction, so that a decrease in rigidity is prevented at the joint between the pair of side wall pieces or the pair of flanges, and thus bending of the container at the joint is suppressed, and shape retention of the container can be improved.

[0008] In one embodiment, the blank sheet has a resin film laminated on a paper base material, and the pair of flange pieces may be joined to each other by fusing the resin film folded between the pair of flange pieces. In this embodiment, the pair of flange pieces can be joined with high rigidity, thereby improving the shape retention of the container.

[0009] In one embodiment, the blank sheet includes a bottom wall sheet portion that forms a bottom wall portion when folded into the shape of the container, and a side wall sheet portion that forms a side wall portion and a flange portion when folded into the shape of the container, and the partition may be formed by folding the bottom wall sheet portion along a first fold line, a second fold line, and a third fold line that extend parallel to each other in a first direction and are arranged in this order in a second direction perpendicular to the first direction. By folding the bottom wall sheet portion along the first fold line, the second fold line, and the third fold line, a partition that divides the storage space into a plurality of small spaces can be formed. By forming this partition, a plurality of contents can be individually stored in the small spaces.

[0010] In one embodiment, the side wall sheet portion includes a plurality of side wall sheet pieces connected to the outer edge of the bottom wall sheet portion, and a window portion having no paper base material and a resin film is formed between a pair of side wall sheet pieces adjacent in the second direction among the plurality of side wall sheet pieces, and the window portion may have an asymmetric shape with respect to the extension line of the second fold line. If the window portion has a symmetric shape, the resin film may be folded between the edges of the pair of side wall sheet pieces, and the resin film may protrude inside or outside the container. In contrast, by making the window portion asymmetric, it is possible to control the fold and folding direction of the resin film.

[0011] In one embodiment, at least a part of the edge of the first sidewall sheet piece, which is one of the pair of sidewall sheet pieces, may extend along an extension of the second fold line. By having a part of the edge of the first sidewall sheet piece extend along the extension of the second fold line, the resin film of the window portion can be folded along the extension of the second fold line when the edges of the pair of sidewall sheet pieces are overlapped and joined. Therefore, it is possible to control the folds and folding direction of the resin film, and the resin film can be folded neatly.

[0012] In one embodiment, the first sidewall sheet piece may be formed by folding the blank sheet so as to be partially overlapped from the inside with the second sidewall sheet piece, which is the other of the pair of sidewall sheet pieces. In this embodiment, by arranging the first sidewall sheet piece on the inside, the resin film of the window portion is folded between the first sidewall sheet piece and the second sidewall sheet piece. Therefore, it is possible to suppress loosening (sagging) of the resin film.

[0013] In one embodiment, the edge of the first side wall sheet piece may include a first side connected to the edge of the bottom wall sheet portion in the first direction and a second side connected to the first side and extending along an extension of the second fold line, and the angle between the edge of the bottom wall sheet portion and the first side may be an acute angle. By making the angle between the edge of the bottom wall sheet portion and the first side an acute angle, it is possible to prevent a gap from being formed between the pair of side wall pieces and the partition when the blank sheet is folded to form a container.

[0014] In one embodiment, the distance between the first fold line and the second fold line in the second direction and the distance between the second fold line and the third fold line in the second direction may be substantially equal, and the angle between the edge of the bottom wall sheet portion and the first side may be 20° or more and 40° or less. In this embodiment, when the blank sheet is folded to form a container, it is possible to suppress the formation of a gap between the pair of side wall pieces and the partition.

[0015] In one embodiment, the edge of the first sidewall sheet piece may include a third side connected to the second side and a fourth side connected to the third side and extending in the first direction, and the fourth side may be disposed in a position shifted from the extension of the second fold line toward the extension of the first fold line in the second direction. By disposing the fourth side in a position shifted from the extension of the second fold line toward the extension of the first fold line, when the blank sheet is folded to form a container, a part of the folded resin film is exposed on the pair of flange pieces. By fusing this exposed resin film, the pair of flange pieces can be firmly joined.

[0016] In one embodiment, an edge of the second side wall sheet piece, which is the other of the pair of side wall sheet pieces, may include a fifth side connected to the edge of the bottom wall sheet portion in the first direction and a sixth side connected to the fifth side and extending in the first direction, and the sixth side may be disposed in a position shifted toward the extension of the second fold line from the extension of the third fold line in the second direction. By disposing the sixth side in a position shifted toward the extension of the second fold line from the extension of the third fold line, it becomes easier to overlap the pair of side wall pieces. Effect of the Invention

[0017] According to the present disclosure, the shape retention of a container can be improved. [Brief description of the drawings]

[0018] [Figure 1] FIG. 1 is a perspective view of a container according to one embodiment. [Diagram 2] 4 is a cross-sectional view perpendicular to the main surfaces of a pair of side wall pieces. FIG. [Diagram 3] 4 is a cross-sectional view taken along the thickness direction of a pair of flange pieces. FIG. [Figure 4] FIG. [Diagram 5] FIG. [Figure 6] FIG. 13 is a perspective view of a container according to another embodiment. [Figure 7] FIG. [Figure 8] 13A and 13B are diagrams showing modified examples of the joining structure of a pair of side wall pieces. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] Hereinafter, an embodiment of the present disclosure will be described in detail with reference to the drawings. In the description of the drawings, the same elements are given the same reference numerals, and duplicated descriptions are omitted. The drawings may be partially simplified or exaggerated for ease of understanding, and the dimensional ratios, angles, etc. are not limited to those shown in the drawings.

[0020] FIG. 1 is a perspective view of a container according to one embodiment. The container 1 shown in FIG. 1 contains contents such as food. The contents are not limited to food. The container 1 shown in FIG. 1 is a paper tray, and is formed by folding a blank sheet 10, as described below. The blank sheet 10 is configured by laminating a paper base material 5 and a resin film 6. Therefore, the inner surface of the container 1 is covered with the resin film 6. The resin film 6 is configured, for example, of a transparent thermoplastic resin.

[0021] In the following description, the three mutually perpendicular axial directions will be described as the "X direction," "Y direction," and "Z direction." The X direction is the direction of the short sides of the container 1, and the Y direction is the direction of the long sides of the container 1. The Z direction is the depth direction of the container 1. In the following description, "inside" means the direction facing the inside of the container 1 (storage space S), and "outside" means the opposite direction to "inside."

[0022] [container] As shown in FIG. 1, the container 1 includes a bottom wall 2, a side wall 3, and a flange 4. The bottom wall 2, the side wall 3, and the flange 4 are formed by laminating a paper base material 5 and a resin film 6. The bottom wall 2 has a substantially rectangular planar shape. The side wall 3 is erected from the outer edge of the bottom wall 2, and together with the bottom wall 2, defines a storage space S for storing contents. The upper part of the storage space S is open, and a substantially rectangular opening M is formed. The contents are put in and taken out through this opening M. The shape of the opening M may be any shape, such as a circle, an ellipse, or a polygon.

[0023] The bottom wall 2 has a pair of bases 21 and a partition 22. Each of the pair of bases 21 is disposed on a plane perpendicular to the Z direction and has a substantially rectangular shape. The partition 22 is disposed between the pair of bases 21 and protrudes toward the opening M. When viewed from the Z direction, the partition 22 extends in the X direction. The length of the partition 22 in the X direction is substantially the same as the width of the bottom wall 2 in the X direction. Both ends of the partition 22 in the X direction abut against a pair of first side walls 31, which will be described later.

[0024] The partition 22 divides the storage space S into two small spaces S1 and S2. Different types of contents are stored in the small spaces S1 and S2. If the contents stored in the container 1 are food, for example, cooked rice is placed in one of the small spaces S1 and S2, and side dishes are placed in the other of the small spaces S1 and S2. The partition 22 also provides rigidity to the container 1 to prevent the bottom wall portion 2 from bending.

[0025] As shown in FIG. 1, the partition 22 has a first inclined surface 23 standing along a first fold line 51 from one of the pair of bases 21, and a second inclined surface 24 standing along a third fold line 53 from the other of the pair of bases 21. The first inclined surface 23 and the second inclined surface 24 are connected via a second fold line 52. The inclination angles of the first inclined surface 23 and the second inclined surface 24 with respect to the base 21 are equal to each other. The partition 22 has a substantially isosceles or equilateral triangular shape when viewed from the X direction. For example, the inclination angles of the first inclined surface 23 and the second inclined surface 24 with respect to the base 21 are 60°.

[0026] The side wall portion 3 has a pair of first side walls 31 facing each other in the X direction, a pair of second side walls 32 facing each other in the Y direction, and a plurality of corner walls 33. The pair of first side walls 31 are erected from the outer edge of the base 21 of the bottom wall portion 2, and the main surfaces thereof are substantially oriented in the X direction. That is, the pair of first side walls 31 define the storage space S from the X direction.

[0027] The pair of first side walls 31 includes a plurality of side wall pieces erected from the outer edge of the bottom wall portion 2. Specifically, each of the pair of first side walls 31 has a pair of side wall pieces 31a, 31b consisting of a first side wall piece 31a and a second side wall piece 31b. The pair of side wall pieces 31a, 31b are disposed adjacent to each other in the Y direction. In addition, the first side wall pieces 31a of the pair of first side walls 31 face each other in the X direction, and the second side wall pieces 31b of the pair of first side walls 31 face each other in the X direction.

[0028] Therefore, the small space S1 is defined by the first side wall pieces 31a of the pair of first side walls 31, one of the pair of second side walls 32, and the first inclined surface 23 of the partition 22. The small space S2 is defined by the second side wall pieces 31b of the pair of first side walls 31, the other of the pair of second side walls 32, and the second inclined surface 24 of the partition 22.

[0029] The pair of side wall pieces 31a, 31b are partially overlapped from the thickness direction. Fig. 2 is a cross-sectional view perpendicular to the main surface of the pair of side wall pieces 31a, 31b. As shown in Fig. 2, an end of the first side wall piece 31a is overlapped with the second side wall piece 31b from the inside of the thickness direction D1 of the pair of side wall pieces 31a, 31b, and an end of the second side wall piece 31b is overlapped with the first side wall piece 31a from the outside of the thickness direction D1.

[0030] The resin film 6 is disposed in a folded state between the pair of side wall pieces 31a, 31b. The pair of side wall pieces 31a, 31b are joined to each other in a partially overlapping state in the thickness direction D1 by fusing the resin film 6 disposed therebetween in a folded state. Note that, as described later, when the pair of flange pieces 41a, 41b are joined, the pair of side wall pieces 31a, 31b do not need to be joined.

[0031] The pair of second side walls 32 are erected from the outer edge of the base 21 of the bottom wall portion 2, and their main surfaces are substantially oriented in the Y direction. That is, the pair of second side walls 32 define the storage space S from the Y direction. The multiple corner walls 33 are respectively disposed between the pair of first side walls 31 and the pair of second side walls 32. The multiple corner walls 33 are erected from the outer edge of the base 21 of the bottom wall portion 2, and are inclined so as to widen outward as they move away from the base 21. In the embodiment shown in FIG. 1, the container 1 has four corner walls 33. The four corner walls 33 rise from the four corners of the bottom wall portion 2.

[0032] The flange portion 4 protrudes outward from the upper end of the side wall portion 3. The flange portion 4 is provided, for example, parallel to the base portion 21 of the bottom wall portion 2 and extends in a substantially rectangular shape so as to surround the outer edge of the opening M. The flange portion 4 is used as a handle to be grasped when lifting the container 1.

[0033] The flange portion 4 has a pair of first flanges 41, a pair of second flanges 42, and a plurality of corner flanges 43. The pair of first flanges 41 includes a plurality of flange pieces that protrude outward from the pair of first side walls 31. Specifically, each of the pair of first flanges 41 has a pair of flange pieces 41a, 41b consisting of a first flange piece 41a and a second flange piece 41b. The pair of flange pieces 41a, 41b are disposed adjacent to each other in the Y direction. The first flange piece 41a protrudes outward from the upper end of the first side wall piece 31a. The second flange piece 41b protrudes outward from the upper end of the second side wall piece 31b.

[0034] The pair of flange pieces 41a, 41b are partially overlapped from the thickness direction. Fig. 3 is a cross-sectional view perpendicular to the main surface of the pair of flange pieces 41a, 41b. As shown in Fig. 3, an end of the first flange piece 41a is overlapped from one side (upper side) of the thickness direction D2 of the pair of flange pieces 41a, 41b onto the second flange piece 41b, and an end of the second flange piece 41b is overlapped from the other side (lower side) of the thickness direction D2 onto the first flange piece 41a. Typically, the thickness direction D2 of the pair of flange pieces 41a, 41b coincides with the Z direction.

[0035] As shown in Fig. 3, the resin film 6 is disposed between the pair of flange pieces 41a, 41b in a folded state. The pair of flange pieces 41a, 41b are joined to each other in a partially overlapping state from the thickness direction D2 by fusing the resin film 6 disposed therebetween in a folded state. Note that, when the pair of side wall pieces 31a, 31b are joined, the pair of flange pieces 41a, 41b do not necessarily have to be joined. That is, at least one of the pair of side wall pieces 31a, 31b and the pair of flange pieces 41a, 41b is joined to each other in a partially overlapping state from the thickness direction.

[0036] The pair of second flanges 42 protrude outward from upper ends of the pair of second side walls 32, respectively. The multiple corner flanges 43 protrude outward from upper ends of the multiple corner walls 33, respectively. In the embodiment shown in FIG. 1, the container 1 has four corner flanges 43 arranged at the four corners of the flange portion 4.

[0037] Both ends of the pair of first flanges 41 and both ends of the pair of second flanges 42 are overlapped with the multiple corner flanges 43. Resin films 6 are arranged in a folded state between the pair of first flanges 41 and the multiple corner flanges 43, and between the pair of second flanges 42 and the multiple corner flanges 43. The pair of first flanges 41 and the pair of second flanges 42 are joined to the multiple corner flanges 43 in a partially overlapping state from the thickness direction by fusing the resin film 6 arranged therebetween in a folded state.

[0038] [Blank sheet] Next, a blank sheet 10 used to create the container 1 will be described. Fig. 4 is a plan view of the blank sheet 10 according to one embodiment. The blank sheet 10 shown in Fig. 4 has a substantially rectangular shape, and is formed by laminating a paper base material 5 and a resin film 6. For convenience, Fig. 4 shows the areas where the paper base material 5 has been cut out (windows W1 and W2, described below) shaded.

[0039] The paper base material 5 is a paper sheet mainly composed of general wood pulp. For example, card paper, Manila cardboard, coated paper, ivory paper, etc. may be used as the paper base material 5. In order to improve printability, a coating layer may be formed on the outer surface of the paper base material 5.

[0040] The resin film 6 is laminated on the entire surface of the paper base material 5. The resin film 6 is made of a thermoplastic resin that can be used as a heel sheet. Although not limited thereto, the resin film 6 may be an ethylene-based resin such as low-density polyethylene resin (LDPE), medium-density polyethylene resin (MDPE), linear low-density polyethylene resin (LLDPE), ethylene-vinyl acetate copolymer (EVA), ethylene-α-olefin copolymer, or ethylene-methacrylic acid resin copolymer, or a blend resin of polyethylene and polybutene, or a polypropylene-based resin such as homopolypropylene resin (PP), propylene-ethylene random copolymer, propylene-ethylene block copolymer, or propylene-α-olefin copolymer. The resin film 6 may be a laminate of these thermoplastic resins.

[0041] 4, the two directions perpendicular to each other are illustrated as an “x direction” and a “y direction.” As shown in FIG.

[0042] The bottom wall sheet portion 11 has a substantially rectangular shape and constitutes the bottom wall portion 2 when folded into the shape of the container 1. The substantially rectangular shape means that the general shape is determined by two sets of two parallel sides, and the two sides with different angles may be connected by one or more oblique sides. That is, the bottom wall sheet portion 11 may have an octagonal or higher polygonal shape. The bottom wall sheet portion 11 has a first fold line 51, a second fold line 52, and a third fold line 53 that extend parallel to each other in the x direction (first direction) and are arranged in this order in the y direction (second direction) perpendicular to the x direction. The bottom wall sheet portion 11 is valley-folded along the first fold line 51 and the third fold line 53, and the bottom wall sheet portion 11 is mountain-folded along the second fold line 52, thereby forming the bottom wall portion 2 having a pair of base portions 21 and a partition 22.

[0043] The distance d1 between the first fold line 51 and the second fold line 12 in the y direction may be substantially equal to the distance d2 between the second fold line 52 and the third fold line 53 in the y direction. By making the distance d1 and the distance d2 equal, the partition 22 having a substantially isosceles or equilateral triangle shape when viewed from the X direction is formed.

[0044] The side wall sheet portion 12 constitutes the side wall portion 3 and the flange portion 4 when folded into the shape of the container 1. The side wall sheet portion 12 includes a pair of first side wall sheet portions 13, a pair of second side wall sheet portions 14, and a plurality of corner wall sheet portions 15. The pair of first side wall sheet portions 13 constitute a pair of first side walls 31 and a pair of first flanges 41 when folded into the shape of the container 1. The pair of second side wall sheet portions 14 constitute a pair of second side walls 32 and a pair of second flanges 42 when folded into the shape of the container 1. The plurality of corner wall sheet portions 15 constitute a plurality of corner walls 33 and a plurality of corner flanges 43 when folded into the shape of the container 1.

[0045] Each of the pair of first sidewall sheet portions 13 has a pair of sidewall sheet pieces 13a, 13b consisting of a first sidewall sheet piece 13a and a second sidewall sheet piece 13b. The pair of sidewall sheet pieces 13a, 13b are connected to an edge 25 of the bottom wall sheet portion 11 in the x direction. The pair of sidewall sheet pieces 13a, 13b are valley-folded along a fold line F1 extending along the edge 25, and the pair of sidewall sheet pieces 13a, 13b are mountain-folded along a fold line F2 extending in the y direction, thereby forming a pair of sidewall pieces 31a, 31b and a pair of flange pieces 41a, 41b.

[0046] The pair of second sidewall sheet portions 14 are connected to an edge 26 of the bottom wall sheet portion 11 in the y direction. The pair of second sidewall sheet portions 14 are valley-folded along a fold line F3 extending along the edge 26, and the pair of second sidewall sheet portions 14 are mountain-folded along a fold line F4 extending in the y direction, thereby forming a pair of second side walls 32 and a pair of second flanges 42.

[0047] The corner wall sheet portions 15 are connected to the outer edge of the bottom wall sheet portion 11. The corner walls 33 and the corner flanges 43 are formed by folding the corner wall sheet portions 15 in a valley direction along a fold line F5 that extends obliquely in the x-direction and the y-direction, and by folding the corner wall sheet portions 15 in a mountain direction along a fold line F6 that is parallel to the fold line F5.

[0048] As shown in Fig. 4, a window portion W1 is formed between the pair of side wall sheet pieces 13a, 13b by cutting out the paper base material 5. The window portion W1 is an area that does not have the paper base material 5 and has only the resin film 6. That is, the resin film 6 is disposed so as to straddle the pair of side wall sheet pieces 13a, 13b. Note that each of the pair of first side wall sheet pieces 13 has a window portion W1, but the shape of the pair of window portions W1 is line-symmetrical with respect to the center line of the blank sheet 10 along the y direction, so that only one of the window portions W1 will be described below.

[0049] When the blank sheet 10 is folded to form the container 1, the resin film 6 of the window portion W1 is disposed in a folded state between the pair of flange pieces 41a, 41b. If the resin film 6 protrudes inward or outward from the container 1 or wrinkles between the pair of flange pieces 41a, 41b, it is not aesthetically pleasing and there is a risk that the joining force of the pair of flange pieces 41a, 41b cannot be secured. When forming the container 1, it is important to control the folds and folding direction of the resin film 6 and design the shape of the window portion W1 so that the resin film 6 is folded neatly.

[0050] 5 is a plan view of the window portion W1. As described above, the window portion W1 is an area that does not have the paper base material 5 and has only the resin film 6, and is defined by the edge 25 of the bottom wall sheet portion 11, the edge 27 of the first side wall sheet piece 13a in the y direction, and the edge 28 of the second side wall sheet piece 13b in the y direction. As shown in FIG. 5, the window portion W1 has an asymmetric shape with respect to the extension line EX2 of the second fold line 52. Specifically, the window portion W1 has an octagonal shape with eight vertices.

[0051] The edge 27 of the first side wall sheet piece 13a includes a first side 61, a second side 62, a third side 63, and a fourth side 64. One end of the first side 61 is connected to the edge 25 of the bottom wall sheet portion 11 and extends in a direction inclined with respect to the x direction and the y direction. The edge 25 of the bottom wall sheet portion 11 and the first side 61 form an angle θ1. The angle θ1 is an acute angle. The angle θ1 is set according to the angle of the first inclined surface 23 with respect to the base 21 of the bottom wall portion 2. For example, when the distance d1 between the first fold line 51 and the second fold line 52 in the y direction and the distance d2 between the second fold line 52 and the third fold line 53 in the y direction are substantially equal, the angle θ1 is set to be 20° or more and 40° or less. The other end of the first side 61 is connected to one end of the second side 62.

[0052] The second side 62 extends in the x direction from the other end of the first side 61 away from the edge 25 of the bottom wall sheet portion 11. Specifically, the second side 62 is disposed on an extension line EX2 of the second fold line 52 and extends along the extension line EX2. The other end of the second side 62 is connected to one end of the third side 63. The third side 63 extends in the y direction from the other end of the second side 62 along an extension line of the fold line F2 away from the edge 28 of the second side wall sheet piece 13b. The other end of the third side 63 is connected to one end of the fourth side 64.

[0053] The fourth side 64 extends in the x direction from the other end of the third side 63 away from the edge 25 of the bottom wall sheet portion 11. In the y direction, the fourth side 64 is disposed at a position shifted toward the extension line EX1 of the first fold line 51 with respect to the extension line EX2 of the second fold line 52.

[0054] The edge 28 of the second side wall sheet piece 13b includes a fifth side 65 and a sixth side 66. One end of the fifth side 65 is connected to the edge 25 of the bottom wall sheet portion 11 and extends in a direction inclined with respect to the x direction and the y direction. The edge 25 of the bottom wall sheet portion 11 and the fifth side 65 form an angle θ2. The angle θ2 is an acute angle. The angle θ2 may be the same angle as the angle θ1. For example, when the distance d1 between the first fold line 51 and the second fold line 52 in the y direction and the distance d2 between the second fold line 52 and the third fold line 53 in the y direction are substantially equal, the angle θ2 is set to be 20° or more and 40° or less. The other end of the fifth side 65 is connected to one end of the sixth side 66.

[0055] The sixth side 66 extends in the x direction from the other end of the fifth side 65 away from the edge 25. As shown in FIG. 5, in the y direction, the sixth side 66 is disposed at a position shifted toward the extension line EX2 of the second fold line 52 from the extension line EX3 of the third fold line 53. The length of the sixth side 66 may be longer than the sum of the lengths of the second side 62 and the fourth side 64. That is, one end (lower end) of the sixth side 66 is disposed closer to the edge 25 than one end (lower end) of the second side 62. In addition, the width w2 between the fourth side 64 and the sixth side 66 in the y direction is larger than the width w1 between the second side 62 and the sixth side 66 in the y direction.

[0056] Also, as shown in Figure 4, window portions W2 having only a resin film 6 without a paper base material 5 are formed between a pair of first side wall sheet portions 13 and a plurality of corner wall sheet portions 15, and between a pair of second side wall sheet portions 14 and a plurality of corner wall sheet portions 15.

[0057] [Container formation method] Next, a method for forming the container 1 using the above-mentioned blank sheet 10 will be described. To form the container 1, first, the bottom wall sheet portion 11 is folded along the first fold line 51, the second fold line 52, and the third fold line 53 to form the bottom wall portion 2 having a pair of base portions 21 and a partition 22, and the side wall sheet portion 12 is folded along the fold lines F1 to F6 to form the side wall portion 3 and the flange portion 4.

[0058] As described above, when the bottom wall sheet portion 11 is folded along the first fold line 51, the second fold line 52, and the third fold line 53, the pair of side wall sheet pieces 13a, 13b move in a direction approaching each other, and the pair of side wall sheet pieces 13a, 13b partially overlap each other in the thickness direction. Then, the resin film 6 of the window portion W1 is disposed between the pair of side wall sheet pieces 13a, 13b. At this time, since the second side 62 of the first side wall sheet piece 13a is disposed on the extension line EX2 of the second fold line 52, the resin film 6 is folded back to the outside of the first side wall sheet piece 13a along the extension line EX2. As a result, as shown in FIG. 2, the resin film 6 is neatly folded between the pair of side wall pieces 31a, 31b composed of the pair of side wall sheet pieces 13a, 13b. Therefore, the resin film 6 is prevented from protruding inward or outward from the container 1.

[0059] Furthermore, by folding back the resin film 6 along the extension line EX2 of the second fold line 52, the resin film 6 is also folded neatly between the pair of flange pieces 41a, 41b formed from the pair of side wall sheet pieces 13a, 13b, as shown in Fig. 3. At this time, since the fourth side 64 is disposed at a position shifted toward the extension line EX1 side from the extension line EX2, a part of the folded resin film 6 is exposed on the second flange piece 41b (see region R in Fig. 3).

[0060] Similarly, when the side wall sheet portion 12 is folded, the pair of first flanges 41 and the pair of second flanges 42 partially overlap the multiple corner flanges 43. Then, the resin film 6 of the window portion W2 is disposed between the pair of first flanges 41 and the multiple corner flanges 43, and between the pair of second flanges 42 and the multiple corner flanges 43.

[0061] Next, the flange portion 4 is heated from above. This causes the resin film 6 folded between the pair of flange pieces 41a, 41b to be heat-sealed. As a result, the pair of flange pieces 41a, 41b are joined in an overlapping state. At this time, the region R of the resin film 6 exposed on the second flange piece 41b is also heat-sealed, so that the pair of flange pieces 41a, 41b are more firmly joined. Similarly, the resin film 6 folded between the pair of first flanges 41 and the multiple corner flanges 43, and between the pair of second flanges 42 and the multiple corner flanges 43, is heat-sealed. In this manner, the container 1 is produced.

[0062] In one embodiment, the overlapping portions of the pair of side wall pieces 31a, 31b may be heated, and the resin film 6 disposed between the pair of side wall pieces 31a, 31b may also be heat-sealed. In this case, the pair of side wall pieces 31a, 31b are joined in a partially overlapping state.

[0063] As described above, in the container 1, the pair of adjacent side wall pieces 31a, 31b or the pair of adjacent flange pieces 41a, 41b are joined together in a partially overlapping state in the thickness direction, so that a decrease in rigidity is prevented at the joint between the pair of side wall pieces 31a, 31b or the pair of flange pieces 41a, 41b. Therefore, the container 1 is less likely to bend, and the shape retention of the container can be improved.

[0064] [Variations] Next, a container according to another embodiment will be described. Fig. 6 is a diagram that shows a container 1A according to another embodiment. For convenience, the resin film 6 is omitted in Fig. 6. In the following, differences from the container 1 shown in Fig. 1 will be mainly described, and overlapping descriptions will be omitted.

[0065] 6, the bottom wall 2 of the container 1 is provided with a first partition 22A and a second partition 22B. When viewed from the Z direction, the first partition 22A extends in the X direction, and the second partition 22B extends in the Y direction. At the position where the first partition 22A and the second partition 22B intersect, a window portion W3 where no paper base material 5 is provided is formed. The first partition 22A and the second partition 22B divide the storage space S of the container 1 into four small spaces S1, S2, S3, and S4.

[0066] Each of the pair of second side walls 32 of the container 1A includes a pair of side wall pieces 32a, 32b. The pair of side wall pieces 32a, 32b are adjacent to each other in the X direction and are partially overlapped from the thickness direction. The pair of second flanges 42 includes a pair of flange pieces 42a, 42b. The pair of flange pieces 42a, 42b protrude outward from the upper ends of the pair of side wall pieces 32a, 32b. The pair of flange pieces 42a, 42b are adjacent to each other in the X direction and are joined to each other in a state where they are partially overlapped from the thickness direction.

[0067] 7 is a plan view of a blank sheet 10A according to another embodiment. The blank sheet 10A is used to produce a container 1A. The blank sheet 10A has a substantially rectangular shape and is configured by laminating a paper base material 5 and a resin film 6.

[0068] The bottom wall sheet portion 11 of the blank sheet 10A has, in addition to the first fold line 51, the second fold line 52, and the third fold line 53 extending parallel to each other in the x direction, a fourth fold line 54, a fifth fold line 55, and a sixth fold line 56 extending parallel to each other in the y direction and arranged in this order in the x direction. The bottom wall sheet portion 11 is valley-folded along the fourth fold line 54 and the sixth fold line 56, and the bottom wall sheet portion 11 is mountain-folded along the fifth fold line 55, thereby forming the second partition 22B.

[0069] The distance d3 between the fourth fold line 54 and the fifth fold line 55 in the x direction and the distance d4 between the fifth fold line 55 and the sixth fold line 56 in the y direction may be substantially equal. By making the distance d3 and the distance d4 equal, the second partition 22B having a substantially isosceles triangular shape when viewed from the Y direction is formed.

[0070] In addition, a window portion W3 is formed in the center of the bottom wall sheet portion 11. The window portion W3 is a portion in which a part of the paper base material 5 of the blank sheet 10A is cut out in a substantially square shape, and does not have the paper base material 5, but has only the resin film 6.

[0071] Each of the pair of second side wall sheet portions 14 of the blank sheet 10A includes a pair of side wall sheet pieces 14a, 14b. The pair of side wall sheet pieces 14a, 14b are adjacent to each other in the x-direction. A window portion W1 is formed between the pair of side wall sheet pieces 14a, 14b. The shape of the window portion W1 is substantially the same as the shape of the window portion W1 formed between the pair of side wall sheet pieces 13a, 13b.

[0072] When forming a container 1A using the blank sheet 10A, first, the bottom wall sheet portion 11 is folded along the first fold line 51, the second fold line 52, the third fold line 53, the fourth fold line 54, the fifth fold line 55, and the sixth fold line 56 to form a bottom wall portion 2 having four base portions 21, a first partition 22A, and a second partition 22B, and at the same time, the side wall sheet portion 12 is folded along the fold lines F1 to F6 to form a side wall portion 3 and a flange portion 4.

[0073] Next, the flange portion 4 is heated from above, and the folded resin film 6 is heat-sealed between the pair of flange pieces 41a, 41b and between the pair of flange pieces 42a, 42b. As a result, the pair of flange pieces 41a, 41b and the pair of flange pieces 42a, 42b are joined in an overlapping state. In this manner, the container 1A is produced.

[0074] In the above-mentioned container 1A, the pair of side wall pieces 32a, 32b or the pair of flange pieces 42a, 42b are joined together while being partially overlapped in the thickness direction, so that the rigidity of the joint between the pair of side wall pieces 32a, 32b or the pair of flange pieces 42a, 42b can be increased. Therefore, the container 1A is less likely to bend, and the shape retention of the container can be improved.

[0075] Although the containers 1, 1A according to various embodiments have been described above, the present invention is not limited to the above-described embodiments and various modifications can be made without departing from the spirit and scope of the invention.

[0076] In the above-described embodiment, the blank sheet 10, 10A in which the paper base material 5 and the resin film 6 are laminated is folded to form the container 1, 1A, but the container 1, 1A does not necessarily have to have the resin film 6. For example, the blank sheet 10, 10A may be formed only from the paper base material 5 without including the resin film 6, and may be joined by adhering the pair of side wall pieces 31a, 31b or the pair of flange pieces 41a, 41b with an adhesive.

[0077] In the embodiment described above, each of the pair of first side walls 31 has a pair of side wall pieces 31a, 31b, but each of the pair of first side walls 31 may have three or more side wall pieces.

[0078] 8, in one embodiment, a piece 70 may be provided on one of the pair of side wall pieces 31a, 31b, a slit 71 may be formed on the other of the pair of side wall pieces 31a, 31b, and the piece 70 may be inserted into the slit 71 to join the pair of side wall pieces 31a, 31b. Furthermore, after a blank sheet 10, 10A made of a paper base material 5 is formed into the shape of a container 1, 1A, a stretchable resin film may be adsorbed to the inner surface of the container 1, 1A by pressure forming.

[0079] The various embodiments described above can be combined to the extent that no contradiction occurs.

[0080] The present disclosure includes the following: [1] A container formed by folding a blank sheet having a paper base material, A bottom wall portion; a side wall portion including a plurality of side wall pieces extending from an outer edge of the bottom wall portion, the side wall portion defining an accommodation space together with the bottom wall portion; a flange portion including a plurality of flange pieces extending outward from upper ends of the plurality of side wall pieces; Equipped with The bottom wall portion has a partition that divides the storage space into a plurality of small spaces, At least one of a pair of adjacent side wall pieces among the plurality of side wall pieces and at least one of a pair of adjacent flange pieces among the plurality of flange pieces are joined to each other in a partially overlapping state in a thickness direction. container. [2] The blank sheet has a resin film laminated on the paper base material, The container according to [1], wherein the pair of flange pieces are joined to each other by fusing the resin film folded between the pair of flange pieces. [3] The blank sheet includes a bottom wall sheet portion that constitutes the bottom wall portion when folded into the shape of the container, and a side wall sheet portion that constitutes the side wall portion and the flange portion when folded into the shape of the container, The container described in [2], wherein the partition is formed by folding the bottom wall sheet portion along a first fold line, a second fold line and a third fold line that extend parallel to each other in a first direction and are arranged in that order in a second direction perpendicular to the first direction. [4] The side wall sheet portion includes a plurality of side wall sheet pieces connected to an outer edge of the bottom wall sheet portion, Among the plurality of side wall sheet pieces, a window portion having the resin film and not having the paper base material is formed between a pair of side wall sheet pieces adjacent to each other in the second direction, The container according to [3], wherein the window portion has an asymmetric shape with respect to an extension line of the second fold line. [5] A container as described in [4], wherein at least a portion of an edge of a first side wall sheet piece, which is one of the pair of side wall sheet pieces, extends along an extension line of the second fold line. [6] A container as described in [5], wherein the first side wall sheet piece is formed by folding the blank sheet so that it is partially overlapped from the inside against the second side wall sheet piece, which is the other of the pair of side wall sheet pieces. [7] An edge of the first side wall sheet piece includes a first side connected to an edge of the bottom wall sheet portion in the first direction, and a second side connected to the first side and extending along an extension of the second fold line, A container as described in [5] or [6], wherein the angle between the edge of the bottom wall sheet portion and the first side is an acute angle. [8] A distance between the first fold line and the second fold line in the second direction is substantially equal to a distance between the second fold line and the third fold line in the second direction; The container described in [7], wherein the angle between the edge of the bottom wall sheet portion and the first side is greater than or equal to 20° and less than or equal to 40°. [9] An edge of the first side wall sheet piece includes a third side connected to the second side and a fourth side connected to the third side and extending in the first direction, The container according to [7] or [8], wherein, in the second direction, the fourth side is positioned at a position shifted toward the extension line of the first fold line from the extension line of the second fold line.

[10] An edge of a second side wall sheet piece, which is the other of the pair of side wall sheet pieces, includes a fifth side connected to an edge of the bottom wall sheet portion in the first direction, and a sixth side connected to the fifth side and extending in the first direction, A container described in any one of [7] to [9], wherein, in the second direction, the sixth side is positioned at a position shifted toward the extension line of the second fold line from the extension line of the third fold line. [Explanation of symbols]

[0081] 1,1A...container, 2...bottom wall portion, 3...side wall portion, 4...flange portion, 5...paper base material, 6...resin film, 10,10A...blank sheet, 11...bottom wall sheet portion, 12...side wall sheet portion, 13a...first side wall sheet piece, 13b...second side wall sheet piece, 22...partition, 31a...first side wall piece, 31b...second side wall piece, 41a...first flange piece, 41b...second flange piece, 51...first fold line, 52...second fold line, 53...third fold line, 61...first side, 62...second side, 63...third side, 64...fourth side, 65...fifth side, 66...sixth side, d1, d2, d3, d4...distance, EX1, EX2, EX3...extension lines, S...storage space, S1, S2, S3, S4...small space, W1...window portion, θ1...angle.

Claims

1. A container formed by folding a blank sheet having a paper substrate, A bottom wall portion; a side wall portion including a plurality of side wall pieces extending from an outer edge of the bottom wall portion, the side wall portion defining an accommodation space together with the bottom wall portion; a flange portion including a plurality of flange pieces extending outward from upper ends of the plurality of side wall pieces; Equipped with The bottom wall portion has a partition that divides the storage space into a plurality of small spaces, At least one of a pair of adjacent side wall pieces among the plurality of side wall pieces and at least one of a pair of adjacent flange pieces among the plurality of flange pieces are joined to each other in a partially overlapping state in a thickness direction. container.

2. The blank sheet has a resin film laminated on the paper base material, The container according to claim 1 , wherein the pair of flange pieces are joined to each other by fusing the resin film folded between the pair of flange pieces.

3. the blank sheet includes a bottom wall sheet portion that constitutes the bottom wall portion when folded into the shape of the container, and a side wall sheet portion that constitutes the side wall portion and the flange portion when folded into the shape of the container, 3. The container according to claim 2, wherein the partition is formed by folding the bottom wall sheet portion along a first fold line, a second fold line, and a third fold line that extend parallel to each other in a first direction and are arranged in this order in a second direction perpendicular to the first direction.

4. The side wall sheet portion includes a plurality of side wall sheet pieces connected to an outer edge of the bottom wall sheet portion, Among the plurality of side wall sheet pieces, a window portion having the resin film and not having the paper base material is formed between a pair of side wall sheet pieces adjacent to each other in the second direction, The container according to claim 3 , wherein the window portion has an asymmetric shape with respect to an extension line of the second fold line.

5. The container according to claim 4 , wherein at least a portion of an edge of a first side wall sheet piece that is one of the pair of side wall sheet pieces extends along an extension of the second fold line.

6. 6. The container according to claim 5, wherein the first side wall sheet piece is formed by folding the blank sheet so as to be partially overlapped from the inside with a second side wall sheet piece which is the other of the pair of side wall sheet pieces.

7. an end edge of the first side wall sheet piece including a first side connected to an end edge of the bottom wall sheet portion in the first direction and a second side connected to the first side and extending along an extension line of the second fold line; The container according to claim 5 , wherein an angle between an edge of the bottom wall sheet portion and the first side is an acute angle.

8. a distance between the first fold line and the second fold line in the second direction is substantially equal to a distance between the second fold line and the third fold line in the second direction; The container according to claim 7 , wherein an angle between an edge of the bottom wall sheet portion and the first side is equal to or greater than 20° and equal to or less than 40°.

9. an end edge of the first side wall sheet piece includes a third side connected to the second side and a fourth side connected to the third side and extending in the first direction; The container according to claim 7 , wherein in the second direction, the fourth side is disposed at a position shifted toward an extension line of the first fold line from an extension line of the second fold line.

10. an edge of a second side wall sheet piece, which is the other of the pair of side wall sheet pieces, includes a fifth side connected to an edge of the bottom wall sheet portion in the first direction, and a sixth side connected to the fifth side and extending in the first direction; The container according to claim 7 , wherein in the second direction, the sixth side is disposed at a position shifted toward an extension line of the second fold line from an extension line of the third fold line.

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