PAPER CONTAINER

Abstract

In a gable roof-type paper container, on an unsealed-side body panel, which is contiguous with an unsealed-side gable wall forming panel through a top portion horizontal folding line, a first auxiliary folding line having a downwardly curved shape has: a left/right end portion arranged near an intersection of an end portion of a body vertical folding line on the left/right of the body panel and a left/right end portion of the top portion horizontal folding line; and a lowest point (U1) located at a center of the body panel in a right-and-left direction thereof, and below the first auxiliary folding line and at a predetermined distance from the first auxiliary folding line, a second auxiliary folding line having a downwardly curved shape has: a left/right end portion arranged at or near the intersection; and a lowest point (U2) located at the center of the body panel in the right-and-left direction.

Claims

1. A paper container, which is a gable roof type and is formed of a paperboard material having a thermoplastic resin laminated on each of a front surface and a back surface of the paperboard material, the paper container comprising: four body panels; a vertical direction sealing panel, which joins edge portions of the four body panels so that the four body panels form a quadrangular body; a pair of gable roof forming panels, which are contiguous with upper ends of the body panels, and include outer-side top sealing panels at upper portions of the pair of gable roof forming panels, respectively, and are opposed to each other; a pair of gable wall forming panels, which are contiguous with upper ends of the body panels through top portion horizontal folding lines, and include inner-side top sealing panels at upper portions of the pair of gable wall forming panels, respectively, and are opposed to each other, any one of the pair of gable wall forming panels being formed into a pouring spout to be unsealed; and a top portion formed by folding the pair of gable wall forming panels between the pair of gable roof forming panels, and by heating, sealing, and tightly closing the outer-side top sealing panels and the inner-side top sealing panels at predetermined positions, wherein on an unsealed-side body panel among the four body panels, which is contiguous with the unsealed-side gable wall forming panel through a top portion horizontal folding line, a first auxiliary folding line having a downwardly curved shape is formed to have: a left end portion arranged at or near an intersection of an end portion of a body vertical folding line on the left of the unsealed-side body panel and a left end portion of the top portion horizontal folding line; a right end portion arranged at or near an intersection of an end portion of a body vertical folding line on the right of the unsealed-side body panel and a right end portion of the top portion horizontal folding line; and a lowest point located at a center of the body panel in a right-and-left direction of the body panel, and below the first auxiliary folding line and at a predetermined distance from the first auxiliary folding line, a second auxiliary folding line having a downwardly curved shape is formed to have: a left end portion arranged at or near the intersection of the end portion of the body vertical folding line on the left of the body panel and the left end portion of the top portion horizontal folding line; a right end portion arranged at or near the intersection of the end portion of the body vertical folding line on the right of the body panel and the right end portion of the top portion horizontal folding line; and a lowest point located at the center of the body panel in the right-and-left direction.

2. The paper container according to claim 1, wherein a length of an interval between the lowest point of the first auxiliary folding line and the lowest point of the second auxiliary folding line is 30 to 50 of a length of an interval between a center of the top portion horizontal folding line and the lowest point of the first auxiliary folding line.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0016] FIG. 1 is a side view for illustrating an unsealed side of an example of a paper container according to an embodiment of the present invention.

[0017] FIG. 2 is a plan view for illustrating a carton blank for the paper container illustrated in FIG. 1.

[0018] FIG. 3 is an explanatory enlarged view for illustrating a part of FIG. 2.

[0019] FIG. 4 is an explanatory view for illustrating another example of a first auxiliary folding line and a second auxiliary folding line of the paper container illustrated in FIG. 1.

[0020] FIG. 5 is an explanatory view for illustrating another example of the first auxiliary folding line and the second auxiliary folding line of the paper container illustrated in FIG. 1.

DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION

[0021] Now, a paper container according to an embodiment of the present invention is described in detail with reference to the drawings.

[0022] FIG. 1 to FIG. 5 are illustrations of an example of a paper container according to an embodiment of the present invention. FIG. 1 is a side view for illustrating an unsealed side of this example of the paper container. FIG. 2 is a plan view for illustrating a carton blank for the paper container illustrated in FIG. 1. FIG. 3 is an explanatory enlarged view for illustrating a part of FIG. 2. FIG. 4 and FIG. 5 are each an explanatory view for illustrating another example of a first auxiliary folding line and a second auxiliary folding line of the paper container illustrated in FIG. 1.

[0023] A gable roof-type paper container 1 in this example is formed of a carton blank 2 that is a paperboard material illustrated in FIG. 2 having a thermoplastic resin laminated on each of a front surface and a back surface thereof. The carton blank includes four body panels 6, 7, 8, and 9 contiguous with each other through body vertical folding lines 3, 4, and 5. At the time of forming the gable roof-type paper container 1, a vertical direction sealing panel 11 contiguous with the body panel 9 through a body vertical folding line 10 is joined to an edge portion 12 of the body panel 6 so that the four body panels 6, 7, 8, and 9 form a quadrangular tubular body 13 of the paper container.

[0024] A pair of gable roof forming panels 16 and 17 are contiguous with an upper end of the body panel 7 and an upper end of the body panel 9 through top portion horizontal folding lines 18 and 19. The pair of gable roof forming panels 16 and 17 include outer-side top sealing panels 14 and 15 at upper portions thereof, respectively, and are opposed to each other. Further, a pair of gable wall forming panels 23 and 24 are contiguous with an upper end of the body panel 6 and an upper end of the body panel 8 through top portion horizontal folding lines 25 and 26. The pair of gable wall forming panels 23 and 24 include inner-side top sealing panels 20 and 21 at upper portions thereof, respectively, and are opposed to each other. Any one of the pair of gable wall forming panels 23 and 24 is formed into a pouring spout 22 and unsealed. In this example, the gable wall forming panel 24 serves as an unsealed-side gable wall forming panel.

[0025] Guide folding lines 27 and 28 are formed on portions of the gable roof forming panels 16 and 17 on the unsealed-side gable wall forming panel 24 side, respectively. Along the guide folding lines 27 and 28, folding of the gable roof forming panels 16 and 17 is guided at the time of unsealing. Further, a pouring spout 31 for a straw is formed in the gable roof forming panel 16. The pouring spout 31 for a straw includes a first half-cut portion 29 formed on a back surface side of the gable roof forming panel 16 so as to serve as a straw slot, and a second half-cut portion 30 formed on a front surface side of the gable roof forming panel 16 so as to surround the first half-cut portion 29.

[0026] Tuck-in folding lines 32, 33, 34, and 35 are formed on the gable wall forming panels 23 and 24, and the gable wall forming panels 23 and 24 are folded in along the tuck-in folding lines 32, 33, 34, and 35. Further, the gable wall forming panel 23 includes a substantially triangular surface portion 36 surrounded by the tuck-in folding lines 32 and 33 and the top portion horizontal folding line 25, and the gable wall forming panel 24 includes a substantially triangular surface portion 37 surrounded by the tuck-in folding lines 34 and 35 and the top portion horizontal folding line 26.

[0027] At the time of forming the paper container 1, the pair of gable wall forming panels 23 and 24 are folded between the pair of gable roof forming panels 16 and 17, and the outer-side top sealing panels 14 and 15 and the inner-side top sealing panels 20 and 21 are heated, sealed, and tightly closed at predetermined positions, thereby forming a gable roof-shaped top portion 38 as illustrated in FIG. 1. In the gable roof-shaped top portion 38 thus formed, a space 39 is defined to have an opening between the pair of gable roof forming panels 16 and 17, the unsealed-side body panel 8, and the unsealed-side gable wall forming panel 24. The space 39 allows fingers to be inserted thereinto in order that the fingers are put on the unsealed-side gable wall forming panel 24 at the time of unsealing of the gable roof-type paper container 1. The substantially triangular surface portion 37 formed on the gable wall forming panel 24 is located on a deep plane of the space 39.

[0028] Further, on the unsealed-side body panel 8, which is contiguous with the unsealed-side gable wall forming panel 24 through the top portion horizontal folding line 26, a first auxiliary folding line 44 having a downwardly curved shape is formed to have: a left end portion 42 arranged at or near an intersection 40 of an end portion of the body vertical folding line 4 on the left of the body panel 8 and a left end portion of the top portion horizontal folding line 26; a right end portion 43 arranged at or near an intersection 41 of an end portion of the body vertical folding line 5 on the right of the body panel 8 and a right end portion of the top portion horizontal folding line 26; and a lowest point U1 located at a center of the body panel 8 in a right-and-left direction thereof.

[0029] In this example, the end portions 42 and 43 of the first auxiliary folding line 44 are arranged near the intersection 40 of the end portion of the body vertical folding line 4 and the end portion of the top portion horizontal folding line 26 and the intersection 41 of the end portion of the body vertical folding line 5 and the end portion of the top portion horizontal folding line 26, respectively. However, the end portions 42 and 43 of the first auxiliary folding line 44 may be connected to the intersections 40 and 41, respectively.

[0030] In addition, on the body panel 8, below the first auxiliary folding line 44 and at a predetermined distance from the first auxiliary folding line 44, a second auxiliary folding line 47 having a downwardly curved shape is formed to have: a left end portion 45 arranged at or near the intersection 40 of the end portion of the body vertical folding line 4 on the left of the body panel 8 and the left end portion of the top portion horizontal folding line 26; a right end portion 46 arranged at or near the intersection 41 of the end portion of the body vertical folding line 5 on the right of the body panel 8 and the right end portion of the top portion horizontal folding line 26; and a lowest point U2 located at the center of the body panel 8 in the right-and-left direction.

[0031] In this example, the end portions 45 and 46 of the second auxiliary folding e arranged near the intersection 40 of the end portion of the body vertical folding line 4 and the end portion of the top portion horizontal folding line 26 and the intersection 41 of the end portion of the body vertical folding line 5 and the end portion of the top portion horizontal folding line 26, respectively, and located away from the end portions 42 and 43 of the first auxiliary folding line 44, respectively. However, the end portions 45 and 46 of the second auxiliary folding line 47 may be connected to the intersections 40 and 41, respectively.

[0032] Further, a length L1 of an interval between the lowest point U1 of the first auxiliary folding line 44 and the lowest point U2 of the second auxiliary folding line 47 is 30% to 50% of a length L2 of an interval between a center of the top portion horizontal folding line 26 and the lowest point U1 of the first auxiliary folding line 44.

[0033] The above-mentioned downwardly curved shapes of the first auxiliary folding line 44 having a downwardly curved shape and the second auxiliary folding line 47 having a downwardly curved shape may be an arc shape or an angled curve shape. In this example, each of the first auxiliary folding line 44 and the second auxiliary folding line 47 is formed into an arc shape, but may be, for example, an inverted V-shaped line having an angled curve shape as illustrated in FIG. 4. Alternatively, each of the first auxiliary folding line 44 and the second auxiliary folding line 47 may be a polygonal line having an angled curve shape as illustrated in FIG. 5.

[0034] According to the paper container configured as described above, two auxiliary folding lines, that is, the first auxiliary folding line 44 and the second auxiliary folding line 47 are formed on the unsealed-side body panel 8. Thus, when a force is applied to fold the body panel 8, the first auxiliary folding line 44 and the second auxiliary folding line 47 effectively guide folding of the body panel 8 as compared to a single auxiliary folding line.

[0035] Therefore, at the time of unsealing, when a top-portion corner portion 49 of the body 13 formed at the upper end portion of the body panel 8 is pushed in toward an inner side of the paper container 1, a force of pushing in the top-portion corner portion 49 of the body 13 is applied to fold the paper container along the first auxiliary folding line 44 and the second auxiliary folding line 47 formed on the body panel 8. Accordingly, the body panel 8 is mountain-folded along the first auxiliary folding line 44 and the second auxiliary folding line 47 with a relatively small force, and thus the top-portion corner portion 48 can be pushed in and dented with a relatively small force.

[0036] If the top-portion corner portion 48 is pushed in with an excessively large force, the body panel 8 is first mountain-folded and dented along the first auxiliary folding line 44 and then mountain-folded and dented along the second auxiliary folding line 47, and thus the body panel 8 is prevented from being dented beyond the second auxiliary folding line 47, thereby being capable of preventing distortion of the body 13.

[0037] Further, in this example, the length L1 of the interval between the lowest point U1 of the first auxiliary folding line 44 and the lowest point U2 of the second auxiliary folding line 47 is 30% to 50% of the length L2 of the interval between the center of the top portion horizontal folding line 26 and the lowest point U2 of the first auxiliary folding line 44. Accordingly, when a force is applied to fold the body panel 8, the first auxiliary folding line 44 and the second auxiliary folding line 47 guide folding of the body panel 8 more effectively.

[0038] Further, when the top-portion corner portion 48 is pushed in with an excessively large force, the body panel 8 is reliably mountain-folded and dented along the first auxiliary folding line 44 and then reliably mountain-folded and dented along the second auxiliary folding line 47, and thus the body panel 8 is more effectively prevented from being dented beyond the second auxiliary folding line 47, thereby being capable of preventing distortion of the body 13 more effectively.

Reference Signs List

[0039] 1 paper container [0040] 2 carton blank [0041] 3, 4, 5 body vertical folding line [0042] 6, 7, 8, 9 body panel [0043] 10 body vertical folding line [0044] 11 vertical direction sealing panel [0045] 12 edge portion [0046] 13 body [0047] 14, 15 outer-side top sealing panel [0048] 16, 17 gable roof forming panel [0049] 18, 19 top portion horizontal folding line [0050] 20, 21 inner-side top sealing panel [0051] 22 pouring spout [0052] 23, 24 gable wall forming panel [0053] 25, 26 top portion horizontal folding line [0054] 27, 28 guide folding line [0055] 29 first half-cut portion [0056] 30 second half-cut portion [0057] 31 pouring spout for straw [0058] 32, 33, 34, 35 tuck-in folding line [0059] 36, 37 substantially triangular surface portion [0060] 38 top portion [0061] 39 space [0062] 40, 41 intersection [0063] 42, 43 end portions of first auxiliary folding line [0064] 44 first auxiliary folding line [0065] 45, 46 end portions of second auxiliary folding line [0066] 47 second auxiliary folding line [0067] 48 top-portion corner portion [0068] U1 lowest point of first auxiliary folding line [0069] U2 lowest point of second auxiliary folding line [0070] L1 length of interval between lowest point of first auxiliary folding line and lowest point of second auxiliary folding line [0071] L2 length of interval between center of top portion horizontal folding line and lowest point of first auxiliary folding line