Covered paper container for liquids

Abstract

The present invention provides a liquid paper container with a cover that can be filled with carbonated beverages and prevents the paper container from bursting due to expansion. [Solution] The liquid paper container 100 consists of a container body 116 made of a paper base material and a spout 118, and a container cover 200 that covers a part of the container body 116. The container body 116 has sealing parts 120a, 120b, 120c that are bonded together on the inside, and flap parts 122a, 122b, 122c that extend from the sealing parts 120a, 120b, 120c. The container body 116 has first bonding parts 124a, 124b, 124c to which the sealing parts 120a, 120b, 120c are bonded, and second bonding parts 126a, 126b, 126c to which the flap parts 122a, 122b, 122c are bonded. The container cover 200 is a covered liquid paper container 300 that covers the flap parts 122a, 122b, 122c.

Description

Technical Field

[0001] The present invention relates to a liquid paper container with a cover.

Background Art

[0002] Carbonated beverages are generally known as preferred beverages that allow consumers to experience a unique carbonated sensation due to the carbon dioxide gas in the beverage when consumed. Since carbon dioxide gas is dissolved in a supersaturated state in carbonated beverages, glass, metal, resin containers, etc. are used as containers for filling to prevent the container from expanding due to the foaming of carbon dioxide gas.

[0003] Glass and metal containers are costly in terms of transportation costs and require time and expense for the recovery operation of empty containers. For example, in Patent Document 1 below, a paper container having a recess at the bottom is described as a paper container for carbonated beverages and alcoholic beverages.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] According to the paper container described in Patent Document 1, even when pressure is applied inside the container due to the expansion of carbonated beverages or the like, the recess provided at the bottom is pushed outward to prevent the paper container from bursting. However, when pressure is applied downward, the seal portion at the bottom is likely to come off, so there is a concern that the seal portion may break.

[0006] <This invention has been made in view of these circumstances, and aims to provide a liquid paper container with a cover that can be filled with carbonated beverages and can prevent the paper container from bursting even when it expands due to the carbonated beverage. [Means for solving the problem]

[0007] The present invention was made to solve the above problems. When forming a container body from a blank sheet, the sealing portion to be bonded is bonded to the inside of the container body, and this sealing portion is bonded to the outside of the container body. Furthermore, a flap portion extending from this sealing portion is bonded to the container body. Furthermore, by covering this flap portion with a container cover, the problems of the present invention can be solved, and the present invention has been completed. The gist of the present invention is as follows. [1] A liquid paper container consisting of a container body made of a paper substrate and a spout provided on the container body, and a container cover that covers at least a part of the container body, The container body comprises at least one sealing portion that seals the paper substrates together, and a flap portion provided on at least one of the paper substrates and extending from the sealing portion. The sealing portion is bonded to the inner sides of the paper substrate when it is used as the container body, which are the inner sides of the container body. The container body has a first adhesive portion that adheres to the outside of the sealing portion, and a second adhesive portion to which the flap portion adheres. The container cover is a liquid paper container with a cover that covers the flap portion. [2] The liquid paper container with a cover according to [1], wherein the second adhesive portion is provided on multiple surfaces of the container body. [3] The container body comprises a body consisting of a front portion, a right side portion, a back portion, and a left side portion, a top portion provided above the body portion, and a bottom portion provided below the body portion, and the right side portion, the left side portion, and the bottom portion have the sealing portion and the first adhesive portion, as described in [1] or [2]. [4] The covered liquid paper container according to any one of [1] to [3], wherein the flap portion extends from the paper substrate on the side opposite to the paper substrate that adheres to the first adhesive portion of the seal portion. [5] A liquid paper container with a cover according to [3] or [4], wherein the container cover protrudes downward from the bottom of the container body. [6] A liquid paper container with a cover according to any one of [3] to [5], wherein the internal shape of the projection diagram of the container cover projected from above is included within a shape obtained by scaling up the projection diagram of the container body projected from above by 1.2 times while maintaining the same shape. [7] A covered paper container for a carbonated beverage, as described in any of [1] to [6]. [Effects of the Invention]

[0008] According to the present invention, it is possible to provide a liquid paper container with a cover that can be filled with carbonated beverages and prevents the paper container from bursting even when it expands due to the carbonated beverage. [Brief explanation of the drawing]

[0009] [Figure 1] This is a top-view perspective showing an example of a liquid paper container with a cover according to the present invention. [Figure 2] This is a perspective view from below showing an example of a liquid paper container with a cover according to the present invention. [Figure 3] This is a top-down perspective view showing an example of a liquid paper container with a cover according to the present invention. [Figure 4] This is a perspective view from below showing an example of a liquid paper container with a cover according to the present invention. [Figure 5] This is a plan view showing the blank sheet used to form the liquid paper container shown in Figure 3. [Figure 6] This is a perspective view of the cover of the liquid paper container with cover according to the present invention. [Figure 7] This is a plan view showing the blank sheet used to form the container cover shown in Figure 6. [Mode for Carrying Out the Invention]

[0010] Hereinafter, a covered liquid paper container according to the present invention will be described with reference to the accompanying drawings.

[0011] [Covered Liquid Paper Container] FIG. 1 and FIG. 2 are diagrams showing an example of the covered liquid paper container of the present invention. FIG. 1 is a perspective view of the covered liquid paper container seen from above, and FIG. 2 is a perspective view of the covered liquid paper container seen from below. Further, FIGS. 3 and 4 are diagrams showing an example of the liquid paper container constituting the covered liquid paper container of the present invention. FIG. 3 is a perspective view of the liquid paper container seen from above, and FIG. 4 is a perspective view of the liquid paper container seen from below. FIG. 5 is a plan view showing a blank sheet for forming the container body of the liquid paper container. Further, FIGS. 6 and 7 are diagrams showing an example of a cover (hereinafter sometimes referred to as "container cover") constituting the covered liquid paper container of the present invention. FIG. 6 is a perspective view of the container cover, and FIG. 7 is a plan view showing a blank sheet for forming the container cover.

[0012] The covered liquid paper container 300 of the present invention comprises a liquid paper container 100 consisting of a container body 116 made of a paper base material and a spout 118 provided on the container body 116, and a container cover 200 covering at least a part of the container body 116. Hereinafter, the liquid paper container 100 and the container cover 200 constituting the covered liquid paper container 300 of the present invention will be described.

[0013] [Liquid Paper Container] The liquid paper container 100 of the present embodiment is a flat-top type liquid paper container 100 having a flat top 104 as shown in FIGS. 3 and 4, and the container body 116 is formed by a blank sheet 10 shown in FIG. 5. The container body 116 of the liquid paper container 100 is made of paper material and consists of a rectangular cylindrical body 102 comprising a front portion 108, a right side portion 110, a back portion 112, and a left side portion 114, a top portion 104 provided above the body portion 102, and a bottom portion 106 provided below the body portion 102. A spout 118 is provided on the top portion 104 of the container body 116. Note that "flat top" means that the top is not convex, such as in a gable-top type. Tops where the height of the front and back sides are different and the top is sloped are included in the definition of a flat top.

[0014] The specific molding method will be described later, but in the liquid paper container 100 shown in Figures 3 and 4, when molding the container body 116, the first right side panel 20a and the second right side panel 20b shown in Figure 5 are bonded together on the inside of the container body 116 using the sealing panels 32a and 32c, thereby forming the sealing portion 120a and the right side portion 110 shown in Figure 3. Similarly, the first left side panel 24a and the second left side panel 24b shown in Figure 5 are bonded together on the inside of the container body 116 using the sealing panels 32b and 32d, thereby forming the sealing portion 120b and the left side portion 114 shown in Figure 4. Furthermore, for the bottom portion 106, the first bottom panel 54a and the second bottom panel 54b shown in Figure 5 are bonded together on the inside of the container body 116 using the sealing panels 33a and 33b, thereby forming the sealing portion 120c and the bottom portion 106 shown in Figure 4.

[0015] The sealing portions 120a, 120b, and 120c formed during the formation of the right side portion 110, the left side portion 114, and the bottom portion 106 are each folded and adhered to the right side portion 110, the left side portion 114, and the bottom portion 106. The locations where the sealing portions 120a, 120b, and 120c of the right side portion 110, the left side portion 114, and the bottom portion 106 are adhered become the first adhesive portions 124a, 124b, and 124c.

[0016] Furthermore, the container body 116 of this embodiment has a flap portion 122a that extends from the sealing portion 120a. The flap portion 122a is connected to the sealing portion panel 32a (see Figure 5) and adheres to the right side portion 110 so as to cover the sealing portion panel 32c (see Figure 5) that adheres to the right side portion 110. Then, this flap portion 122a is bent from the right side portion 110 and adhered to the back portion 112. The locations where the flap portion 122a of the right side portion 110 and the back portion 112 are adhered become the second adhesive portion 126a.

[0017] Similarly, on the left side portion 114, a flap portion 122b is provided extending from the seal portion 120b. The flap portion 122b is provided in connection with the seal portion panel 32b (see Figure 5) and is bonded to the left side portion 114 so as to cover the seal portion panel 32d (see Figure 5) which is bonded to the left side portion 114. Then, this flap portion 122b is bent from the left side portion 114 and bonded to the back portion 112. The locations where the flap portion 122b of the left side portion 114 and the back portion 112 are bonded become the second bonded portion 126b.

[0018] Furthermore, a flap portion 122c is also provided on the bottom portion 106, extending from the seal portion 120c. The flap portion 122c is connected to the seal portion panel 33a (see Figure 5) and adheres to the bottom portion 106 by covering the seal portion panel 33b (see Figure 5) which is bonded to the bottom portion 106. This flap portion 122c is then bent from the bottom portion 106 and bonded to the back portion 112. The locations where the flap portion 122c of the bottom portion 106 and the back portion 112 are bonded become the second bonded portion 126c.

[0019] In this way, each flap portion 122a, 122b, and 122c is adhered to the right side portion 110 and the back portion 112, the left side portion 114 and the back portion 112, and the bottom portion 106 and the back portion 112, and the second adhesive portions 126a, 126b, and 126c are provided across multiple surfaces. Furthermore, as shown in Figures 1 and 2, since the flap portions 122a, 122b, and 122c are covered by the container cover 200 described later, even if one surface of each flap portion 122a, 122b, and 122c peels off, the other surfaces can be held down by the container cover 200, thus preventing the flap portions 122a, 122b, and 122c from peeling off and preventing the liquid paper container 100 from breaking.

[0020] Next, we will describe the blank sheet 10 on which the container body 116 of this embodiment is formed, and the method for forming the container body 116 using this blank sheet 10. The blank sheet 10 has a top panel 40 on which a front panel 19 and a back panel 22 are connected via top horizontal fold lines 41a and 41b, respectively. The first right side panel 20a and the first left side panel 24a are connected to the front panel 19 perpendicular to the top panel 40 via vertical fold lines 12 and 14 of the body, respectively. The second right side panel 20b is connected to the rear panel 22 perpendicular to the top panel 40, via vertical fold line 16 of the body in the same direction as the first right side panel 20a, and the second left side panel 24b is connected to the rear panel 22 perpendicular to the top panel 40, via vertical fold line 18 of the body in the same direction as the first left side panel 24a.

[0021] On the side opposite the front panel 19 to the first right side panel 20a and the first left side panel 24a, there are sealing panels 32a and 32b, respectively, via sealing vertical fold lines 30a and 30b. Similarly, on the side opposite the back panel 22 to the second right side panel 20b and the second left side panel 24b, there are sealing panels 32c and 32d, respectively, via sealing vertical fold lines 30c and 30d.

[0022] Furthermore, the sealing panels 32a and 32b connected to the first right side panel 20a and the first left side panel 24a are connected to flap panels 34a and 34b on the opposite side from the first right side panel 20a and the first left side panel 24a, respectively. The flap panels 34a and 34b are provided with vertical flap fold lines 36a and 36b, respectively.

[0023] Furthermore, the top panel 40 has top folded panels 42 and 44 connected to it via top vertical fold lines 46 and 48, perpendicular to the direction in which the front panel 19 and the back panel 22 are connected. The top folded panels 42 and 44 are provided with top diagonal fold lines 42a and 44a. Also, sealing panels 32e and 32f are connected to the top folded panels 42 and 44 on the side opposite to the top panel 40. Furthermore, the top folded panel 42 is connected to the first right side panel 20a and the second right side panel 20b via top horizontal fold lines 41c and 41d, respectively, in the direction perpendicular to the top panel 40. Also, the top folded panel 44 is connected to the first left side panel 24a and the second left side panel 24b via top horizontal fold lines 41e and 41f, respectively, in the direction perpendicular to the top panel 40.

[0024] On the sides of the front panel 19 and the rear panel 22 opposite to the top panel 40, a pair of opposing first bottom panels 54a and second bottom panels 54b are connected via bottom lateral fold lines 52 and 53 to form the bottom 106. In addition, on the side of the first bottom panel 54a opposite to the front panel 19, and on the side of the second bottom panel 54b opposite to the rear panel 22, sealing panels 33a and 33b are connected via sealing lateral fold lines 31a and 31b. Furthermore, a flap panel 34c is connected to the side of the sealing panel 33a opposite to the first bottom panel 54a. The flap panel 34c is provided with a flap lateral fold line 38 that separates the positions where the bottom 106 and the back 112 are bonded when the container body 116 is formed.

[0025] Furthermore, bottom fold panels 56a and 56b are connected to the opposite sides of the top fold panels 42 and 44 of the first right side panel 20a and the first left side panel 24a via bottom transverse fold lines 52a and 52b. The bottom fold panels 56a and 56b are connected to the first bottom panel 54a in a direction perpendicular to the direction in which the first right side panel 20a and the first left side panel 24a are connected. Similarly, bottom fold panels 56c and 56d are connected to the opposite sides of the top fold panels 42 and 44 of the second right side panel 20b and the second left side panel 24b via bottom transverse fold lines 53a and 53b. The bottom fold panels 56c and 56d are connected to the second bottom panel 54b in a direction perpendicular to the direction in which the second right side panel 20b and the second left side panel 24b are connected.

[0026] Bottom folded panels 56a, 56b, 56c, and 56d are provided with bottom diagonal fold lines 60a, 60b, 60c, and 60d, respectively. Furthermore, the bottom folding panels 56a and 56b are connected to sealing panels 32g and 32h on the opposite side from the first bottom panel 54a, respectively, and to sealing panels 33c and 33d on the opposite side from the first right side panel 20a and the first left side panel 24a. Furthermore, the bottom folding panels 56c and 56d are connected to sealing panels 32i and 32j on the opposite side of the second bottom panel 54b, respectively, and to sealing panels 33e and 33f on the opposite side of the second right side panel 20b and the second left side panel 24b.

[0027] The top panel 40 of the blank sheet 10 configured in this way has a plug attachment opening 64 formed in the center of the top panel 40 for attaching a plug 118. The top panel 40 and the top folded panels 42 and 44 are also provided with a central horizontal fold line 62 that continuously folds the blank sheet 10 in half.

[0028] In forming a liquid paper container 100 (container body 116) using such a blank sheet 10, first, the central horizontal fold line 62, which is continuously provided on the top panel 40 and the top folded panels 42 and 44, is folded in a mountain fold, and the opposing sealing panels 32e, sealing panels 32a and 32c, sealing panels 32g and 32i, sealing panels 33c and 33e, sealing panels 33a and 33b, sealing panels 33d and 33f, sealing panels 32h and 32j, sealing panels 32b and 32d, and sealing panels 32f are bonded together using an adhesive or the like. In this embodiment, the sealing portion is formed by bonding each sealing panel together. Note that the surface side in Figure 5 is the outside when it becomes the container body 116. That is, each sealing panel is bonded together on the inside of the container body 116.

[0029] Next, the vertical fold lines 12, 14, 16, and 18 of the body are folded in a mountain fold to form the square body 102. At this time, the top horizontal fold lines 41a and 41b are folded in a mountain fold, the top horizontal fold lines 41c, 41d, 41e, and 41f are folded in a valley fold, and the top diagonal fold lines 42a and 44a of the top folded surface panels 42 and 44 are folded in a mountain fold to form the top 104. Similarly, for the bottom 106, when the vertical fold lines 12, 14, 16, and 18 of the body are mountain-folded to form the square body 102, the horizontal fold lines 52 and 53 of the bottom are mountain-folded, the horizontal fold lines 52a, 52b, 53a, and 53b of the bottom are valley-folded, and the diagonal fold lines 60a, 60b, 60c, and 60d of the bottom folded surface panels 56a, 56b, 56c, and 56d of the bottom are mountain-folded to form the bottom 106.

[0030] Furthermore, when the body portion 102, top portion 104, and bottom portion 106 are formed, the sealing portion 120a (see Figure 3), formed by bonding the sealing portion panels 32a and 32c together, is folded inwards by valley folding along the sealing portion vertical fold line 30c and mountain folding along the sealing portion vertical fold line 30a, causing the sealing portion panel 32c to be folded toward the second right side panel 20b (right side portion 110 in Figure 3). Similarly, for the left side portion 114, the sealing portion 120b (see Figure 4), formed by bonding the sealing portion panels 32b and 32d together, is folded along the vertical fold line 30d of the sealing portion (valley fold) and along the vertical fold line 30b of the sealing portion (mountain fold), causing the sealing portion panel 32d to be folded towards the second left side portion panel 24b (left side portion 114 in Figure 4).

[0031] The folded sealing panels 32c and 32d are bonded to the second right side panel 20b and the second left side panel 24b, respectively, using adhesive. That is, the outside of the sealing parts 120a and 120b are bonded to the outside of the formed container body 116. The areas where these sealing panels 32c and 32d are bonded to the second right side panel 20b (right side portion 110) and the second left side panel 24b (left side portion 114) become the first bonded portions 124a and 124b.

[0032] Similarly, for the bottom portion 106, the sealing portion 120c (see Figure 4), formed by bonding the sealing portion panels 33a and 33b together, is folded by valley folding along the sealing portion's horizontal fold line 31b and mountain folding along the sealing portion's horizontal fold line 31a, causing the sealing portion panel 33b to be folded towards the second bottom panel 54b (bottom portion 106 in Figure 4). The folded sealing panel 33b is bonded to the second bottom panel 54b using an adhesive or the like. That is, the outside of the sealing portion 120c is bonded to the outside of the formed container body 116 (bottom 106). The area where this sealing panel 33b is bonded to the second bottom panel 54b becomes the first bonded portion 124c.

[0033] After bonding the sealing panels 32c, 32d to the second right side panel 20b and the second left side panel 24b at the first adhesive parts 124a, 124b, the flap panels 34a, 34b are bonded to the second right side panel 20b and the second left side panel 24b. Furthermore, the flap panels 34a, 34b can be folded towards the back panel 112 by folding them along the vertical flap fold lines 36a, 36b provided on the flap panels 34a, 34b. The sides of the flap panels 34a, 34b that face the sealing panels 32a, 32b are bonded to the second right side panel 20b and the second left side panel 24b, while the sides of the vertical flap fold lines 36a, 36b that face the sealing panels 32a, 32b are bonded to the back panel 22. The areas where these flap panels 34a and 34b are bonded to the second right side panel 20b, the second left side panel 24b, and the back panel 22 become the second bonding areas 126a and 126b.

[0034] Similarly, with respect to the bottom 106, the seal panel 33b and the second bottom panel 54b are bonded at the first adhesive portion 124c, and then the flap panel 34c and the second bottom panel 54b are bonded together. Furthermore, the flap panel 34c can be folded towards the back portion 112 by folding it along the flap lateral fold line 38 provided on the flap panel 34c. The side of the flap panel 34c on the seal panel 33a side of the flap lateral fold line 38 is bonded to the second bottom panel 54b, and the side of the flap lateral fold line 38 opposite to the seal panel 33a is bonded to the back panel 22. The areas where the flap panel 34c is bonded to the second bottom panel 54b and the areas where it is bonded to the back panel 22 become the second adhesive portion 126c.

[0035] In this way, by providing the second adhesive portions 126a, 126b, and 126c, to which the flap panels 34a, 34b, and 34c are bonded, on multiple surfaces of the second right side panel 20b, the second left side panel 24b, the second bottom panel 54b, and the back panel 22 that form the body portion 102, the adhesion during the molding of the container body can be strengthened.

[0036] After the flap panels 34a, 34b, and 34c are bonded together at the second adhesive parts 126a, 126b, and 126c, the top folded panels 42 and 44, which are folded along the top diagonal fold lines 42a and 44a, are folded to the right side section 110 and the left side section 114, and then bonded to the right side section 110 and the left side section 114 with adhesive or the like. Similarly, the bottom folded panels 56a and 56c, which are joined together by the sealing panels 33c and 33e and folded along the bottom diagonal fold lines 60a and 60c, are folded towards the right side portion 110 and attached to the right side portion 110 with adhesive or the like. The bottom folded panels 56b and 56d, which are joined together by the sealing panels 33d and 33f and folded along the bottom diagonal fold lines 60b and 60d, are folded towards the left side portion 114 and attached to the right side portion 110 with adhesive or the like. (See Figures 3 and 4)

[0037] The molding method for the liquid paper container 100 (container body 116) described above is just one example, and the liquid paper container 100 of the present invention is not limited to the blank sheet 10 described above. In addition, the spout 118 is attached before the first opposing sealing panels are bonded together to form the sealing portion.

[0038] <Container cover> Figures 6 and 7 show examples of container covers that constitute the liquid paper container with a cover of the present invention. Figure 6 is a perspective view of the container cover, and Figure 7 is a plan view showing the blank sheet from which the container cover is formed. The container cover 200 is made of paper material and, as shown in Figure 6, consists of a front panel 204, a right side panel 206, a rear panel 208, and a left side panel 210, and a rectangular cylindrical cover body 202 with openings at the top and bottom.

[0039] Figure 7 is a plan view showing the blank sheet 250 on which the container cover 200 of this embodiment is formed. The blank sheet 250 is connected via vertical fold lines 252, 254, and 256 and comprises four body panels 258, 260, 262, and 264 corresponding to the front panel 204, right side panel 206, rear panel 208, and left side panel 210. Furthermore, a side seal panel 268 is connected to the front panel 204 of the blank sheet via a vertical side seal fold line 266, which seals to the other open end (left side panel 210) of the blank sheet 250. In addition, a folded surface panel 276 is connected to the lower end of each of the four body panels 258, 260, 262, and 264 via a horizontal fold line 272.

[0040] In forming a container cover 200 using such a blank sheet 250, first, the vertical fold lines 252, 254, and 256 of the body and the vertical fold line 266 of the side seal are folded in a mountain fold, and the side seal panel 268 is sealed to the body panel 264 (left side panel 210) on the other open end side of the blank sheet to form a rectangular cover body 202. After forming the cover body 202, the horizontal fold line 272 is folded in a mountain fold, and the folded surface panel 276 is folded inward into the cover body 202 and sealed. This maintains the strength of the end of the bottom opening of the container cover 200 and prevents the covered liquid paper container from tipping over when it is placed upright.

[0041] The container cover 200 is preferably made of paper material, and the same paper material as that used for the liquid paper container 100 described above can be used for the container cover.

[0042] Returning to Figures 1 and 2, the liquid paper container 300 with a cover of the present invention is formed by inserting the liquid paper container 100 shown in Figure 3 through the upper or lower opening of the container cover 200 shown in Figure 6. The height of the cover body 202 of the container cover 200 is set higher than the height of the body 102 of the liquid paper container 100. In Figures 1 and 2, the top 104 of the liquid paper container 100 and the upper end of the cover body 202 of the container cover 200 are aligned to form the covered liquid paper container 300. By making the height of the cover body 202 higher than the height of the body 102 of the liquid paper container 100, as shown in Figures 1 and 2, even if the entire surface of the body 102 of the liquid paper container 100 is covered with the container cover 200, the lower end of the container cover 200 can protrude from the bottom 106 of the liquid paper container 100. As a result, even if the liquid paper container 100 expands and its bottom 106 is no longer flat, the liquid paper container 300 with the cover can be stood upright on the lower end of the container cover 200, thus preventing the liquid paper container 100 from tipping over.

[0043] Furthermore, as described above, the liquid paper container 100 has its flap portions 122a and 122b folded and bonded at the back portion 112. By covering the entire body portion 102 of the liquid paper container 100 with the cover body portion 202 of the container cover 200, the first bonded portions 124a and 124b and the second bonded portions 126a and 126b can be covered by the container cover 200, thus preventing the flap portions 122a and 122b from peeling off from the right side portion 110, the left side portion 114, and the back portion 112. Regarding the bottom portion 106, the flap portion 122c is folded along the flap's horizontal fold line 38 (see Figure 5) and adhered to the back portion 112. Since the flap portion 122c adhered to this back portion can be covered by the container cover 200, it is possible to prevent the flap portion 122c from peeling off from the back portion 112.

[0044] In Figures 1 and 2, the height of the cover body 202 of the container cover 200 is set higher than the height of the body 102 of the liquid paper container 100, and covers the entire body 102 of the liquid paper container 100. However, the cover body 202 does not need to cover the entire body 102 of the liquid paper container 100. Preferably, in the vertical direction of the body 102 of the liquid paper container 100, the length of the cover body 202 is such that the upper and lower ends of the cover body 202 cover at least a portion of the top folded panels 42, 44 and the bottom folded panels 56a, 56b, 56c, 56d. More preferably, the top folded panels 42, 44 and the bottom folded panels 56a, 56b, 56c, 56d are covered by more than half of their respective vertical lengths, and it is particularly preferable that more than 80% of the top folded panels 42, 44 and the bottom folded panels 56a, 56b, 56c, 56d are covered. This prevents the flap portions 122a, 122b, and 122c from peeling off from the body portion 102.

[0045] Furthermore, it is preferable that the internal shape of the container cover 200, when projected from above, is contained within a shape obtained by scaling up the projection of the container body 116 from above by 1.2 times. When a carbonated beverage is filled into the liquid paper container 100, the liquid paper container 100 expands, so the internal shape of the container cover 200 can be scaled up by 1.2 times to account for this expansion. Also, even if the container body 116 expands, the container cover 200 can hold down the flap portions 122a, 122b, and 122c, thus preventing the flap portions 122a, 122b, and 122c from peeling off and the liquid paper container 100 from rupturing.

[0046] In this way, when molding the right side portion 110, the left side portion 114, and the bottom portion 106 of the container body 116, the insides of each sealing portion panel are bonded together, and these bonded sealing portions 120a, 120b, and 120c are bonded to the outside of the body portion 102. Furthermore, flap portions 122a, 122b, and 122c are bonded to the outside of the body portion 102 so as to cover the sealing portions 120a, 120b, and 120c. In addition, by covering the flap portions 122a, 122b, and 122c with the cover body portion 202 of the container cover 200, it is possible to prevent the container body from rupturing even if the container body expands due to the expansion of the contents. Therefore, even if the contents expand and the container body expands, the container body can be prevented from rupturing, making it suitable for use with carbonated beverages.

[0047] (Paper material for the container body and container cover) Next, the layer configuration of the paper material used in the container body 116 and container cover 200 of the liquid paper container 100 of the present invention will be described. Note that the following is just one example of a paper material, and the liquid paper container 100 and container cover 200 of the present invention are not limited to the following layer configuration. Various paper materials can be used as long as they do not hinder the effects of the present invention.

[0048] The paper material used for the container body 116 and container cover 200 of the liquid paper container 100 of the present invention can be composed of a paper base layer, a first thermoplastic resin layer provided on both sides of the paper base layer, and a second thermoplastic resin layer. A polyamide resin layer and / or a gas barrier layer may also be provided between each layer. In the following description, the side with the second thermoplastic resin layer will be the inner surface side of the liquid paper container, and the side with the first thermoplastic resin layer will be the outer surface side. Furthermore, the container body 116 of the liquid paper container 100 will be described below, but the container cover 200 can have a similar configuration.

[0049] <Paper base layer> The paper substrate constituting the paper substrate layer is not particularly limited as long as it does not hinder the effects of the present invention, and known paper substrates used for liquid paper containers can be used. Specifically, it may be any of the following types of paper manufactured using pulp or recycled pulp: acidic paper manufactured with a papermaking pH in the acidic range, pseudo-neutral paper manufactured with a papermaking pH in the pseudo-neutral range, neutral paper manufactured with a papermaking pH in the neutral range, or alkaline paper manufactured with a papermaking pH in the alkaline range.

[0050] The basis weight of the base material is 200-400 g / m². 2 It is preferable that the basis weight is within this range. 2 With the above specifications, the rigidity is sufficient, and there is no concern about molding defects. On the other hand, 400g / m 2 The rigidity is not too high if it is below this level, making it easy to mold. From this perspective, the basis weight of the paper substrate is 250-350 g / m². 2 It is more preferable that the range be 280-320 g / m². 2 It is even more preferable that it be within the range of [a certain range].

[0051] <First thermoplastic resin layer, second thermoplastic resin layer> The first thermoplastic resin layer and the second thermoplastic resin layer are formed to protect the front and back surfaces of the paper substrate. The first thermoplastic resin layer and the second thermoplastic resin layer may be formed from the same material or from different materials, as long as they can protect the front and back surfaces. Furthermore, the first thermoplastic resin layer and the second thermoplastic resin layer may be formed as a single layer or as multiple layers.

[0052] Furthermore, since paper containers are manufactured using this paper substrate, it is preferable that the first thermoplastic resin layer and the second thermoplastic resin layer have heat-sealing properties. The heat-sealing properties are not particularly limited, and for example, there are methods of heating and melting polyethylene using the action of hot air, ultrasonic vibration, high-frequency induction, high-frequency dielectric, or laser light to seal it. Of these, hot air sealing is preferred because, due to the mechanism of the filling machine, it is possible to stably melt and seal the polyethylene of the liquid paper container.

[0053] The first thermoplastic resin layer and the second thermoplastic resin layer may be polyethylene layers. The polyethylene layers may be polyethylene derived from fossil fuels, polyethylene derived from biomass, or a mixture thereof.

[0054] In the production of biomass-derived ethylene, it is preferable to use biomass-derived fermented ethanol obtained from plant materials as a raw material. Examples of plant materials include, but are not limited to, corn, sugarcane, and beets. Furthermore, the method for polymerizing monomers containing biomass-derived ethylene is not particularly limited and can be carried out by known methods.

[0055] The polyethylene constituting the first thermoplastic resin layer and the second thermoplastic resin layer preferably contains either low-density polyethylene (LDPE) with a biomass content of 70% or more, or linear low-density polyethylene (LLDPE). A biomass content of 70% or more significantly reduces the amount of fossil fuels used, thereby reducing the environmental burden and adequately contributing to measures against global warming and the creation of a circular economy. From this viewpoint, a biomass content of 80% or more is more preferable, 90% or more is even more preferable, and it may even be 100%. Furthermore, the polyethylene resin may be composed of a mixed resin of high-density polyethylene (HDPE) and low-density polyethylene resin.

[0056] Furthermore, if there is an odor derived from biomass, it is preferable to include a deodorant in the first thermoplastic resin layer and the second thermoplastic resin layer. Examples of deodorants include porous materials, metal oxides, and chemical adsorbents having acidic or basic groups. Note that biomass content is only found in materials of biological origin. 14 It can be identified by measuring C.

[0057] When the first thermoplastic resin layer and the second thermoplastic resin layer are single layers, the thickness of the first thermoplastic resin layer is preferably in the range of 10 to 30 μm, and the thickness of the second thermoplastic resin layer is preferably in the range of 5 to 30 μm. When the first thermoplastic resin layer and the second thermoplastic resin layer consist of multiple layers, the outermost layer is preferably within the above range. If the thickness of the first thermoplastic resin layer is 10 μm or more, the heat sealability is sufficient, and if it is 30 μm or less, the rebound is not strong and molding is easy. From the above viewpoint, the thickness of the first thermoplastic resin layer is more preferably in the range of 10 to 20 μm, and even more preferably in the range of 13.5 to 16.5 μm. Furthermore, if the thickness of the second thermoplastic resin layer is 5 μm or more, the heat sealability is sufficient, and if it is 30 μm or less, the rebound is not strong and molding is easy. From the above viewpoint, the thickness of the second thermoplastic resin layer is more preferably in the range of 5 μm to 20 μm, and even more preferably in the range of 8.5 to 11.5 μm. Furthermore, the melt flow rate (hereinafter sometimes referred to as "MFR") of the first thermoplastic resin layer and the second thermoplastic resin layer is preferably 0.8 to 10 g / 10 min. When the MFR is within this range, sufficient strength and good film-forming properties can be obtained.

[0058] The method for forming the first thermoplastic resin layer and the second thermoplastic resin layer is not particularly limited, but for example, a resin composition for forming the first thermoplastic resin layer and the second thermoplastic resin layer can be prepared, and this resin composition can be extruded onto a paper substrate layer to form the first thermoplastic resin layer and the second thermoplastic resin layer by an extrusion lamination method.

[0059] Furthermore, the first thermoplastic resin layer and the second thermoplastic resin layer are not limited to a single layer, but may be formed from multiple layers. When formed from multiple layers, each layer may be formed by preparing a resin composition and then forming each layer by extrusion lamination, or by extruding the resin compositions of each layer while stacking them, or by co-extrusion.

[0060] <Polyamide resin layer> The paper material used for the container body of the liquid paper container of the present invention preferably has a polyamide resin layer. By providing a polyamide resin layer, light transmittance is suppressed, preventing deterioration of the quality of the contents inside the container, and gas barrier properties can also be provided. The polyamide layer can be provided on either the side facing the first thermoplastic resin layer or the side facing the second thermoplastic resin layer with respect to the paper substrate layer. A polyamide resin layer can be formed by manufacturing a polyamide film from a composition containing polyamide resin and laminating this polyamide film onto a paper substrate layer. Alternatively, a composition containing polyamide resin can be prepared and formed on a paper substrate layer by extrusion lamination.

[0061] <Gas barrier layer> The paper material used in the container body of the liquid paper container of the present invention may have a gas barrier layer. The gas barrier layer is a layer that prevents the quality of the contents from deteriorating due to oxidation or the like. The gas barrier layer can also be provided on either the side facing the first thermoplastic resin layer or the side facing the second thermoplastic resin layer relative to the paper substrate layer.

[0062] As the gas barrier layer, commonly used aluminum foil can be used. Furthermore, from the viewpoint of resource recycling, it is preferable to include polyethylene terephthalate (hereinafter also referred to as "PET") as the gas barrier layer. By using PET for the gas barrier layer, it can be recycled in the same way as milk cartons, etc.

[0063] Furthermore, by including recycled PET as a material for PET, an even more environmentally friendly laminate can be created. As for PET, a mixture of recycled PET and virgin PET can be used, and from an environmental standpoint, the recycled PET content is preferably 5% or more, more preferably 80% or more, and it may even be 100% recycled PET.

[0064] As a gas barrier layer, a known vapor-deposited film can be used, which is a PET film substrate on which aluminum oxide and / or silicon oxide are deposited on one side. In particular, a vapor-deposited film in which aluminum oxide and silicon oxide are deposited in two dimensions is preferred. Such a vapor-deposited film has high gas barrier properties and excellent flexibility. The deposition method is not particularly limited, and methods such as vacuum deposition, sputtering, physical deposition, or chemical deposition can be used.

[0065] The thickness of the gas barrier layer is preferably in the range of 1 to 30 μm. A thickness of 1 μm or more provides sufficient barrier properties, while a thickness of 30 μm or less does not result in strong repulsion, making molding easier. From this viewpoint, the thickness of the gas barrier layer is more preferably in the range of 5 to 20 μm, and even more preferably in the range of 9 to 15 μm.

[0066] (adhesive layer) Furthermore, an adhesive layer may be provided between each layer constituting the paper material. Providing an adhesive layer can improve the adhesion (bonding) of each layer. From the viewpoint of improving the adhesion of each layer, it is preferable to use low-density polyethylene resin or linear low-density polyethylene resin as the adhesive layer, and linear low-density polyethylene resin is particularly preferred. The adhesive layer may be a single layer or consist of multiple layers. [Examples]

[0067] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to the following examples.

[0068] The paper material used exhibits a layered structure consisting of the following nine layers. (Outer side) / First thermoplastic resin layer-1 / First thermoplastic resin layer-2 / Paper material / Adhesive layer-1 / Adhesive layer-2 / Barrier layer / Second thermoplastic resin layer-1 / Second thermoplastic resin layer-2 / Second thermoplastic resin layer-3 / (Inner side) (Materials used) (1) First thermoplastic resin layer-1: Polyethylene (LDPE), thickness 15 μm (2) First thermoplastic resin layer-2: Polyethylene (LDPE), thickness 20 μm (3) Paper material: 313g / m 2 Base paper thickness: 450 μm (4) Adhesive layer-1: Polyethylene (LDPE), 15 μm thick (5) Adhesive layer-2: Polyethylene (LLDPE), 15 μm thick (6) Barrier layer: PET, 12 μm thick (7) Second thermoplastic resin layer-1: Polyethylene (LLDPE) Thickness 30 μm (8) Second thermoplastic resin layer-2: Polyethylene (LLDPE) Thickness 10 μm (9) Second thermoplastic resin layer-3: Polyethylene (LLDPE) Thickness 10 μm A liquid paper container was fabricated using the blank sheet shown in Figure 5, which consists of the paper material with the above layer structure. A container cover was then fabricated using the blank sheet shown in Figure 7, which consists of the same paper material.

[0069] The fabricated liquid paper containers were filled with room-temperature strong carbonated water (Tomomasu Beverage Co., Ltd., "Strong Soda") (after container formation, the spout was opened and the contents were filled from the spout area, and the spout was closed after filling). After being left at room temperature for 1 minute, the containers were shaken by hand three times alternating between up and down about 1 meter, and the occurrence of container breakage and rupture was evaluated. Four types of containers were used: only the liquid paper container formed from the blank sheet shown in Figure 5, the liquid paper container formed from the blank sheet shown in Figure 5 with a container cover formed from the blank sheet shown in Figure 7 attached, and commercially available "Tetra Prisma 330ml" (Tetra Pak) and "NP-PAK REGULAR 500ml with spout" (Nippon Paper Industries Co., Ltd.) paper containers (each was filled to full capacity for evaluation). The above containers were visually inspected after storage. In the case of liquid paper containers with covers, the flap portion did not peel off when covered with the container cover, and the liquid paper container did not rupture, allowing for problem-free storage. In the case of liquid paper containers alone, as the liquid paper container expanded, the flap portion peeled off from the body panel and burst. Bursting of the paper containers was also observed in commercially available "Tetra Prisma 330ml" (manufactured by Tetra Pak) and "NP-PAK REGULAR 500ml with spout" (manufactured by Nippon Paper Industries Co., Ltd.). Additionally, while the bottom of the liquid paper container with a cover was observed to bulge, it was possible to make it stand upright by extending the container cover outwards from the liquid paper container. [Industrial applicability]

[0070] The present invention can alleviate pressure caused by the expansion of the contents and prevent the seal from breaking, making it suitable for use as a paper container for carbonated beverages, alcoholic beverages, and the like. [Explanation of Symbols]

[0071] 10 Blank Sheets 12, 14, 16, 18 Vertical fold lines on the torso 19 Front Panel 20a First right side panel 20b Second right side panel 22 Rear Panel 24a First left side panel 24b Second left side panel 30a, 30b, 30c, 30d Seal vertical fold line 31a, 31b Horizontal fold line of the seal portion 32a, 32b, 32c, 32d, 32e, 32f, 32g, 32h, 32i, 32j, 33a, 33b, 33c, 33d, 33e, 33f Seal panel 34a, 34b, 34c Flap Panel 36a, 36b Flap vertical fold line 38 Flap lateral fold line 40 Top Panel 41a, 41b, 41c, 41d, 41e, 41f Top transverse fold line 42, 44 Top folded panel 42a, 44b Top diagonal fold line 46, 48 Vertical fold lines at the top 52, 52a, 52b, 53, 53a, 53b Bottom transverse fold line 54a First bottom panel 54b Second bottom panel 56a, 56b, 56c, 56d Bottom folding panel 60a, 60b, 60c, 60d Bottom diagonal fold line 62 Center horizontal fold line 64 Opening for plug installation 100 liquid paper containers 102 Torso 104 Top 106 Bottom 108 Front view 110 Right side section 112 Back section 114 Left side part 116 Container body 118 Mouthpiece 120a, 120b, 120c sealing section 122a, 122b, 122c Flap section 124a, 124b, 124c First adhesive section 126a, 126b, 126c Second adhesive section 200 container cover 202 Cover Body 204 Front Panel 206 Right side panel 208 Rear Panel 210 Left side panel 250 Blank Sheets 252, 254, 256 Vertical fold lines on the body 258, 260, 262, 264 Body panels 266 Side seal vertical fold line 268 Side seal panel 272 Horizontal line 276 Folding Panel 300 Covered liquid paper containers

Claims

1. A liquid paper container consisting of a container body made of a paper substrate and a spout provided on the container body, and a container cover that covers at least a part of the container body, The container body comprises at least one sealing portion that seals the paper substrates together, and a flap portion provided on at least one of the paper substrates and extending from the sealing portion. The sealing portion is bonded to the inner sides of the paper substrate when it is used as the container body, which are the inner sides of the container body. The container body has a first adhesive portion that adheres to the outside of the sealing portion, and a second adhesive portion to which the flap portion adheres. The container cover is a liquid paper container with a cover that covers the flap portion.

2. The liquid paper container with a cover according to claim 1, wherein the second adhesive portion is provided on multiple surfaces of the container body.

3. The container body consists of a body section comprising a front section, a right side section, a back section, and a left side section, a top section provided above the body section, and a bottom section provided below the body section. A liquid paper container with a cover according to claim 1 or 2, wherein the right side portion, the left side portion, and the bottom portion have the sealing portion and the first adhesive portion.

4. The liquid paper container with a cover according to claim 1 or 2, wherein the flap portion extends from the paper substrate on the side opposite to the paper substrate that adheres to the first adhesive portion of the seal portion.

5. The liquid paper container with a cover according to claim 3, wherein the container cover protrudes downward from the bottom of the container body.

6. The liquid paper container with a cover according to claim 3, wherein the internal shape of the projection diagram of the container cover projected from above is included within a shape obtained by scaling up the projection diagram of the container body projected from above by 1.2 times while maintaining the same shape.

7. A liquid paper container with a cover according to claim 1 or 2, wherein the contents are a carbonated beverage.

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