Manufacturing method and manufacturing device for assembled paper container

Abstract

[Problem] To provide an assembled paper container that can suppress leaking or oozing of accommodated contents from an accommodation part of a container body. [Solution] An assembled paper container 1 comprises a container body 11 having an accommodation part 12, and a resinous film 3 coated on an inner surface of the container body 11, and is characterized in that: the container body 11 has a bottom surface 121, a plurality of lateral surfaces 122, and a flange part 13; an upper surface 131 of the flange part 13 has a step 22 that develops when turn-back pieces 13a and 13b are bonded so as to overlap each other after assembling, and that extends outward from the accommodation part 12 side, the step 22 being reduced when an edge part 31 of the upper turn-back piece is thrusted toward the lower turn-back piece 13b; and the resinous film 3 is substantially flat even over the step 22 at a portion at which the resinous film 3 is coated on the upper surface of the flange part 13 of the container body 11.

Description

[Technical field]

[0001] This invention ,set The present invention relates to a method for manufacturing a stand-up paper container and an apparatus for manufacturing this stand-up paper container. [Background technology]

[0002] Conventionally, there has been known a prefabricated paper container in which a tray-shaped container body having a flange at the upper end is assembled from blank sheets made mainly of paper. Some of these prefabricated paper containers have a thermoplastic resin film having resin properties attached to the inner surface of the container body, including the upper surface of the flange (see Patent Documents 1 and 2, etc.). Because of their resin properties, these prefabricated paper containers with resin films are mainly used as trays or bowls for storing food, etc.

[0003] Furthermore, compared to plastic containers, the prefabricated paper container is an environmentally friendly product, for example, because it can suppress the generation of secondary microplastics in the environment. Furthermore, the resin film can be peeled off from the container body, and the resin film and the paper container body can be separated, and the resin film and the container body can be recycled separately. Due to these advantages, it is expected that the prefabricated paper container can be used as a packaging container for food and the like and a storage container for food and the like by applying, for example, Modified Atmosphere Packaging (MAP). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 6-293334 [Patent Document 2] JP 2019-172339 A Summary of the Invention [Problem to be solved by the invention]

[0005] In the container body of such a conventional assembled paper container, a gap is formed on the upper surface of the flange portion due to the close proximity of the end faces of the blank sheets. At present, it is difficult to completely fill this gap even if the inner surface of the container body, including the upper surface of the flange portion, is covered with a resin film. Furthermore, the resin film is thin, and when the resin film is covered on the inner surface of the container body, including the upper surface of the flange portion, for example, by vacuum pressure, the resin film is sucked into the gap, making it difficult to close the gap with the resin film alone.

[0006] Also, a packaging method has been developed in which the air in the storage section of the container body is replaced with a food gas suitable for packaging the food (e.g., MAP). When this packaging method is applied to a prefabricated paper container with a resin film, a top seal is attached to the resin film on the upper surface of the flange section. However, because the top seal is also thin, even if the top seal is attached to the resin film, a cavity is created along the gap between the upper surface of the resin film and the lower surface of the top seal. In other words, it is difficult to completely seal the cavity even with the top seal. Moreover, both ends of the cavity are open. Therefore, the storage section of the container body communicates with the outside of the container body through this cavity.

[0007] For the reasons described above, even if the storage section of an assembled paper container with a resin film is covered with a top seal, there is a risk that the contents will leak or seep out of the storage section through the cavity.

[0008] The present invention has been devised in view of the above-mentioned problems, and its object is to provide a container capable of preventing leakage or seepage of the contents from the storage portion of the container body. Group The present invention provides a method for manufacturing a stand-up paper container and an apparatus for manufacturing the stand-up paper container. [Means for solving the problem]

[0013] No. 1The manufacturing method of the assembled paper container according to the invention is a manufacturing method of an assembled paper container which is assembled from blank sheets mainly made of paper and includes a container body having a storage section and a resin film covering the inner surface of the container body, the manufacturing method including a box-making process in which a plurality of side surfaces are raised from the bottom surface of the blank sheet to form the storage section of the container body, the upper portions of the plurality of side surfaces are folded back, and the folded back pieces of the blank sheets are attached so as to overlap each other, and a step is formed on the upper surface thereof extending outward from the storage section, and a flange portion is formed extending outward from the storage section to form the container body, and the resin film is disposed on the inner surface of the container body assembled in the box-making process, a manufacturing device including a lower mold on which the container body is placed, a suction covering section provided in the lower mold for sucking air between the resin film and the resin film to cover the inner surface of the container body with the resin film, an upper mold facing the lower mold and sandwiching the resin film between the lower mold and the upper mold, a flange pressing section accommodated in the upper mold for pressing the flange portion of the container body and the resin film on the flange portion, and a step reducing recess provided in the lower mold below the flange pressing section of the upper mold, The surface of the region of the resin film that crosses the step is The suction covering portion Aspirate, The step constitutes The edge of the upper folded piece 、 The lower folded piece the step reduction recess having a width equal to or greater than the length between the edges of the upper folded piece, To The lower folded piece is attached to the flange pressing portion. Push By the step reducing / resin film covering process in which the lower folded piece is bulged downward in the area where it contacts the upper folded piece to reduce the step, and air between the container body and the resin film is extracted through the gap around both, thereby covering the inner surface of the container body with the resin film.

[0014] No. 2 The method for producing an assembled paper container according to the present invention is as follows: 1 In the present invention, the step reduction resin frame After the film covering step, the resin film covering the upper surface of the flange portion is Above the upper surface of the flange portion, the upper portion of the step is pushed and the step is traversed. The method further comprises a top seal attaching step of attaching a top seal as described above.

[0015] No. 3The manufacturing device for assembled paper containers according to the invention is a manufacturing device for assembled paper containers which is assembled from blank sheets whose main material is paper and includes a container body having a containing section, and a resin film covering the inner surface of the container body, and includes a lower mold on which the container body is placed, a suction covering section provided in the lower mold for sucking air between the resin film and the inner surface of the container body and causing the resin film to cover the inner surface of the container body, an upper mold which faces the lower mold and sandwiches the resin film between the lower mold and the upper mold, a flange pressing section which is received in the upper mold and presses a flange section of the container body and the resin film on the flange section, and a flange pressing section provided in the lower mold below the flange pressing section of the upper mold. and a step reducing recess for reducing the height of the recess; The resin film is placed, and a surface of the resin film in a region that crosses the step of the flange portion of the container body is The above When the suction cover part is sucked, the edge of the upper folded piece forming the step 、 Lower folded side the step reduction recess having a width equal to or greater than the length between the edges of the upper folded piece, To The lower folded piece is attached to the flange pressing portion. Push By The lower folded piece is caused to bulge downward in a region where the lower folded piece contacts the upper folded piece, thereby reducing the step. thing It is characterized by:

[0016] No. 4 The manufacturing apparatus for assembled paper containers according to the present invention is 3 Manufactured by the manufacturing device for assembled paper containers according to the invention The resin film covering the upper surface of the flange portion of the assembled paper container is provided with a top sheet. A manufacturing apparatus for an assembled paper container, which covers the container portion by attaching a top seal to the top seal, A seal head is disposed above the assembled paper container, and a seal bucket is disposed below the assembled paper container. and wherein the upper portion of the seal bucket is made of an elastic material and the lower portion of the seal bucket is made of a hard material. It is characterized by being made of quality materials. Effect of the Invention

[0017] According to the present invention having the above-mentioned configuration, it is possible to provide a prefabricated paper container that is capable of preventing the contained contents from leaking or seeping out from the containing portion of the container body. [Brief description of the drawings]

[0018] [Figure 1] FIG. 1(a) is a plan view showing an assembly-type paper container according to an embodiment of the present invention, FIG. 1(b) is a side view showing the assembly-type paper container of FIG. 1(a), and FIG. 1(c) is an oblique view showing the assembly-type paper container of FIG. 1(a). [Diagram 2] FIG. 2 is a development view showing a blank sheet used in the prefabricated paper container of FIG. [Diagram 3] FIG. 3 is an enlarged cross-sectional view of the portion seen from the arrow AA in FIG. [Figure 4] FIG. 4 is a plan view showing an aspect in which the storage section of the assembly-type paper container of FIG. 1 is covered with a top seal. [Diagram 5] 5(a) is an enlarged cross-sectional view of a portion viewed from the arrow BB in FIG. 4, and FIG. 5(b) is an enlarged view of a portion C in FIG. 5(a). [Figure 6] FIG. 6 is a flowchart showing steps in a manufacturing method for a prefabricated paper container according to an embodiment of the present invention. [Figure 7] 7(a) and 7(b) are schematic cross-sectional views showing an example of a manufacturing apparatus for a prefabricated paper container according to an embodiment of the present invention. [Figure 8] 8(a) to 8(c) are explanatory views for explaining the main part of the manufacturing apparatus of FIG. 7 in an enlarged manner. [Figure 9] FIG. 9 is a schematic block diagram showing an example of a manufacturing system for assembly-type paper containers according to an embodiment of the present invention. [Figure 10] Figures 10(a) to 10(c) are explanatory diagrams for explaining enlarged main parts of a pressing machine serving as a manufacturing device for assembly-type paper containers that attaches top seals to assembly-type paper containers according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0020] [Embodiment] A prefabricated paper container 1 according to an embodiment of the present invention includes a container body 11 and a resin film 3 covering the inner surface of the container body 11, as shown in Figs. 1(a) to 1(c).

[0021] The container body 11 has a storage section 12 and a flange section 13. The container body 11 is assembled from one blank sheet 2 made mainly of paper as shown in FIG. 2. In FIG. 2, dotted lines indicate "valley folds" and dashed lines indicate "mountain folds". The valley folds and mountain folds are, for example, perforations, half cuts, or lines. The solid lines in the blank sheet 2 indicate "slits". The container body 11 is constructed by making the "valley folds" and "mountain folds" in the blank sheet 2 and bonding the folded pieces 13a, 13b together so that they overlap each other.

[0022] In this embodiment, the storage section 12 has eight side surfaces 122 rising from the bottom surface 121. The storage section 12 can be configured so long as it has three or more side surfaces 122.

[0023] The flange portion 13 is continuous with the upper end of each side surface 122 and extends outward from the storage portion 12. An upper surface 131 of the flange portion 13 has two steps 22 at each of the four corners, which extend outward from the storage portion 12 side and are generated when the folded pieces 13a, 13b of the blank sheet 2 are attached to each other so as to overlap each other after assembly.

[0024] As shown in FIG. 3, the step 22 is reduced by pushing the edge 31 of the upper folded piece 13a towards the lower folded piece 13b.

[0025] The resin film 3 covers the inner surface of the container body 11 including the upper surface 131 of the flange portion 13. As shown in Fig. 3, the resin film 3 has small undulations even above the step 22 and is generally flat.

[0026] Examples of resins suitable for use in the resin film 3 for covering the inner surface of the container body 11 include thermoplastic resins such as polyolefins, such as polyethylene (PE) and polypropylene (PP), polyesters, such as polyvinyl chloride and polyethylene terephthalate (PET), ethylene-vinyl acetate copolymers (EVA), ethylene-acrylic acid copolymers, polyamides, polyvinylidene chloride, polystyrene, polycarbonate, polybutene, and polyvinyl alcohol. The resin film 3 may be a single film made of any of the above materials, or may be a film made of a mixture of a plurality of the above materials. The resin film 3 may be a single-layer film, or may be a laminated film made of a plurality of layers.

[0027] Next, a description will be given of the prefabricable paper container 1 in which the container section 12 is covered with a top seal 4, in accordance with the above-mentioned embodiments.

[0028] As shown in FIG. 4, the assembled paper container 1 can package and store food or other contents by covering the storage section 12 with the top seal 4. The top seal 4 is attached to the resin film 3 on the upper surface 131 of the flange section 13. As a result, the top seal 4 covers the storage section 12. In this embodiment, the top seal 4 is attached to the resin film 3 above the upper surface 131 of the flange section 13, crossing the step 22. When attaching the top seal 4 to the resin film 3, the top seal 4 is pressed by a press machine while being heated in a pressing area 32 shown by a dotted line. In this embodiment, the outer part of the step 22 is designed to fit within the width of the pressing area 32. As a result, the outer part of the step 22 can be reliably pressed by the press machine and further reduced as shown in FIG. 5(a) and FIG. 5(b).

[0029] Here, above the step 22, the lower surface of the top seal 4 can be sufficiently thermocompression bonded to the upper surface of the resin film 3, and the top seal 4 can be firmly attached to the upper surface of the resin film 3 even if there is a reduced, gentle step 22.

[0030] In addition, the resin film 3 is pressed against the top seal 4 at the step 22 and is formed so as to be folded over into three or more layers, which applies a reaction force to the top seal 4 being pressed, making it easier to thermocompress the lower surface of the top seal 4 to the upper surface of the resin film 3.

[0031] Next, a manufacturing method of the prefabricated paper container 1 according to the embodiment of the present invention will be described with reference to FIG.

[0032] First, in the manufacturing method of the assembly type paper container 1 according to the embodiment of the present invention, the blank sheet cutting step S1 of cutting and forming the blank sheet 2 is carried out to manufacture the blank sheet 2.

[0033] Next, a box-making process S2 is performed in which the container body 11 is assembled from the blank sheets 2 manufactured by cutting out in the blank sheet cutting process S1.

[0034] Next, the resin film 3 is placed on the inner surface of the container body 11 assembled in the box making process S2, the surface of the area of ​​the resin film 3 that crosses the step 22 is sucked, and the edge 31 of the upper folded piece 13a is pushed toward the lower folded piece 13b to reduce the step 22, and the step reduction / resin film covering process S3 is performed in which the resin film 3 is covered on the inner surface of the container body 11 by, for example, applying pressure from above the resin film 3 while extracting the air between the container body 11 and the resin film 3 from the gap around them using vacuum compressed air. Note that, although vacuum compressed air has been exemplified as a method for covering the container body 11 with the resin film 3, the air between the container body 11 and the resin film 3 may be extracted only by sucking the air between them from the gap between them or by applying pressure from above the resin film 3.

[0035] Next, a trimming process S4 is performed in which excess resin film 3 is removed from around the assembled paper container 1 to which the top seal 4 produced in the step reducing / resin film covering process S3 has not yet been attached.

[0036] Next, an article accommodating step S5 is performed in which an article such as food is accommodated in the accommodation portion 12 of the prefabricable paper container 1 from which the excess peripheral resin film 3 has been removed in the trimming step S4.

[0037] Finally, a top seal attachment process S6 is performed in which a top seal 4 is attached to the resin film 3 covering the upper surface of the flange portion 13 of the assembled paper container 1 in a state in which food or other contents are contained in the storage portion 12 in the content storage process S5, using a pressing machine to press the upper portion of the step 22 above the upper surface of the flange portion 13 and cross this step 22.

[0038] In this way, the prefabricated paper container 1 is manufactured, and the method for manufacturing the prefabricated paper container 1 according to this embodiment is completed.

[0039] Next, a manufacturing apparatus 600 for the prefabricated paper container 1 according to an embodiment of the present invention will be described with reference to FIG.

[0040] As shown in Figures 7(a) and 7(b), the manufacturing apparatus 600 for the prefabricated paper container 1 according to the embodiment of the present invention is a new manufacturing apparatus capable of manufacturing the prefabricated paper container 1 according to this embodiment. This manufacturing apparatus 600 covers the container body 11 with the flange portion 13 with the resin film 3, and can reduce the step 22 during the covering.

[0041] This manufacturing apparatus 600 includes a lower mold 610, a suction cover portion 611, an upper mold 620, a flange pressing portion 630, and a step reducing recess 610a (see FIGS. 8(a) to 8(c)).

[0042] The container body 11 is placed on the lower mold 610.

[0043] The suction cover part 611 is provided on the lower mold 610 and is connected to a vacuum pump 640. The suction cover part 611 is configured to suck the resinous film 3 through the container body 11 placed on the lower mold 610 so that air escapes from the gap between the container body 11 and the periphery thereof.

[0044] The upper die 620 faces the lower die 610 and is movable up and down. The resinous film 3 is sandwiched between the lower die 610 and the upper die 620, and when the upper die 620 is brought into close contact with the lower die 610 with the resinous film 3 sandwiched therebetween, a processing space in a substantially sealed state is formed. In this processing space, the resinous film 3 covers the accommodation portion 12 and the flange portion 13 by, for example, vacuum compressed air.

[0045] The flange pressing portion 630 is housed in the upper mold 620. The flange pressing portion 630 is supported on a top plate portion 621 of the upper mold 620 by an expandable and contractible elastic member 632 such as a spring. The flange pressing portion 630 presses the flange portion 13 and the resin film 3 on the flange portion 13, for example, during vacuum pressure.

[0046] 8(a) to 8(c), the step reducing recess 610a is provided below the flange pressing portion 630 of the upper die 620 in the lower die 610, and has a width exceeding the length between the edges 31, 31 of the upper folded piece 13a, which presses the edge 31 of the upper folded piece 13a constituting the step 22 toward the lower folded piece 13b when the resinous film 3 is placed and the surface of the region of the resinous film 3 that crosses the step 22 of the flange portion 13 of the container body 11 is sucked by the suction covering portion 611, thereby reducing the step 22. In this embodiment, the suction covering portion 611 sucks the resinous film 3 in the direction toward the container body 11. In addition, the width of the step-reducing recess 610a may be set to be equal to the length between the edges 31, 31 of the upper folded piece 13a. However, as in this embodiment, it is preferable to set the width of the step-reducing recess 610a to be greater than the length between the edges 31, 31 of the upper folded piece 13a. under This is preferable because it prevents excessive shearing force from being applied to the folded-back piece 13b on the side.

[0047] Here, the manner in which the step 22 is reduced will be described.

[0048] As shown in Figures 8(a) and 8(b), the container body 11 and the resin film 3 are positioned and attached between a lower mold 610 having a step-reducing recess 610a and a flange pressing portion 630 so as to cross the step 22 of the flange portion 13.

[0049] 8(c), the flange pressing portion 630 is lowered toward the lower mold 610 to reduce the step 22. Then, the flange pressing portion 630 is raised to remove the assembled paper container 1 from the manufacturing apparatus 600.

[0050] Finally, the excess resin film 3 around the periphery of the prefabricable paper container 1 is trimmed to complete the prefabricable paper container 1 shown in Figs.

[0051] In this manner, the manufacturing apparatus 600 for the prefabricated paper container 1 according to this embodiment makes it possible to manufacture the prefabricated paper container 1.

[0052] Next, a manufacturing system 700 for the prefabricated paper container 1 according to an embodiment of the present invention will be described with reference to FIG.

[0053] A manufacturing system 700 for a prefabricated paper container 1 according to an embodiment of the present invention covers a container body 11 with a flange portion 13 with a resin film 3 while winding up the resin film 3 wound around a feed roller 710 with a winding roller 720.

[0054] As shown in FIG. 9, the manufacturing system 700 includes a feed roller 710, a take-up roller 720, a heater 730, the manufacturing device 600, and a trimming machine 740.

[0055] A roll of the band-shaped resin film 3 is attached to the feed roller 710.

[0056] One end of the strip-shaped resin film 3 is attached to the winding roller 720, which winds up the strip-shaped resin film 3. The strip-shaped resin film 3 advances along the feed direction W from the feed roller 710 toward the winding roller 720.

[0057] The heater 730 is disposed between the feed roller 710 and the take-up roller 720 and heats the strip-shaped resin film 3 .

[0058] The manufacturing apparatus 600 is as described above, and is disposed between the heater 730 and the take-up roller 720 .

[0059] The trimming machine 740 is disposed between the manufacturing apparatus 600 and the take-up roller 720, and trims the prefabricable paper container 1 manufactured by the manufacturing apparatus 600. In this way, the prefabricable paper container 1 is detached from the strip-shaped resin film 3.

[0060] Thus, the manufacturing system 700 for the prefabricated paper container 1 according to this embodiment includes the manufacturing apparatus 600. Therefore, the manufacturing system 700 is capable of manufacturing the prefabricated paper container 1. Moreover, the manufacturing system 700 is capable of continuously manufacturing the prefabricated paper container 1 from the strip-shaped resin film 3.

[0061] Finally, using Figures 10(a) to 10(c), we will explain a pressing machine as a manufacturing apparatus according to an embodiment of the present invention, which attaches a top seal 4 to the resin film 3 covering the upper surface of the flange portion 13 in the assembled paper container 1 manufactured by the above-mentioned manufacturing apparatus 600, thereby covering the storage portion 12.

[0062] 10(a) to 10(c), this pressing machine includes a seal head 810 disposed above the top seal 4, and seal buckets 820, 830 disposed below the assembled paper container 1. The seal bucket upper part 820 is made of an elastic material such as rubber, and the seal bucket lower part 830 is made of a hard material such as metal.

[0063] Then, the seal head 810 is lowered and heated to attach the top seal 4 to the flange portion 13 of the prefabricated paper container 1, resulting in the usage form shown in Figures 4, 5(a) and 5(b).

[0064] Furthermore, since the seal bucket upper part 820 is made of an elastic material such as rubber, due to the elastic deformation of this seal bucket upper part 820, when the top seal 4 is attached, as described above, the outer part of the step 22 can be reliably pressed by a pressing machine, and further reduced as shown in Figures 5(a) and 5(b).

[0065] According to the embodiment of the present invention described above, the top seal 4 can be thermocompression bonded to the upper surface of the resinous film 3 above the step 22, and the top seal 4 can easily cover the upper surface of the resinous film 3 above the step 22 even if there is a step 22.

[0066] In addition, the resin film 3 is pressed by the top seal 4 at the step 22 and is formed so as to be folded over in multiple layers, which applies a reaction force to the top seal 4 being pressed, making it easier to thermocompress the lower surface of the top seal 4 to the upper surface of the resin film 3.

[0067] Thus, according to this embodiment, an assembly-type paper container 1 can be provided that, by using the resin film 3 and the top seal 4, is capable of preventing the contents from leaking or seeping out of the storage section 12 of the container body 11.

[0068] Here, an experimental verification was carried out by preparing multiple samples of the same number of samples under the same conditions as much as possible for a prefabricated paper container not to which the present invention is applied and the prefabricated paper container 1 to which the present invention is applied, and comparing them. The verification results showed that while most of the samples in the prefabricated paper container not to which the present invention is applied experienced leakage or seepage of the contained contents, none of the samples in the prefabricated paper container 1 to which the present invention is applied experienced leakage or seepage of the contained contents from the container section 12 of the container body 11.

[0069] Although the embodiment of the present invention has been described above, this embodiment is presented as an example and is not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the gist of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are included in the scope of the invention and its equivalents described in the claims. [Explanation of symbols]

[0070] 1. Assembled paper container 11 Container body 12 Storage section 121 Bottom 122 Side 13 Flange 131 Top surface 13a Folding piece 13b Folding piece 2 Blank Sheets 22 Steps 3. Plastic film 31 Edge of upper fold 32 Pressing Area 4 Top seal 600 Manufacturing equipment 610 Lower mold 610a Step reduction recess 611 Suction covering part 620 upper mold 621 Top plate 630 Flange holder 632 Elastic members 640 Vacuum Pump 700 Manufacturing System 710 Feeding roller 720 Winding roller 730 heating machine 740 Trimming Machine 810 Seal Head 820 Seal bucket upper part 830 Seal bucket lower part S1 Blank sheet cutting process S2 Box manufacturing process S3 Step reduction / resin film covering process S4 Trimming process S5 Storage process S6 Top seal attachment process W Feed direction

Claims

1. The method for manufacturing an assembled paper container is provided with a container body having a storage section, assembled from blank sheets mainly made of paper, and a resin film covering the inner surface of the container body. hand, a box-making process in which a plurality of side surfaces are raised from a bottom surface of the blank sheet to form the storage section of the container body, the upper portions of the plurality of side surfaces are folded back, and the folded back pieces of the blank sheet are attached to each other so as to overlap each other, forming a flange portion on the upper surface of the blank sheet that has a step extending outward from the storage section and that extends outward from the storage section, thereby assembling the container body; The resin film is placed on the inner surface of the container body assembled in the box-making process, and the resin film is formed by using a manufacturing device including a lower mold on which the container body is placed, a suction covering section provided in the lower mold for sucking air between the resin film and the inner surface of the container body and causing the resin film to cover the inner surface of the container body, an upper mold facing the lower mold and sandwiching the resin film between the lower mold and the upper mold, a flange pressing section accommodated in the upper mold for pressing the flange portion of the container body and the resin film on the flange portion, and a step reducing recess provided in the lower mold below the flange pressing section of the upper mold. a step reducing / resin film covering step in which the surface of the area crossing the step is sucked by the suction covering part, and the edge of the upper folded piece constituting the step is pushed together with the lower folded piece via the flange pressing part toward the step reducing recess that is disposed on the side of the lower folded piece and has a width equal to or greater than the length between the edges of the upper folded piece, thereby causing the lower folded piece to bulge downward in the area in contact with the upper folded piece, thereby reducing the step, and air between the container body and the resin film is extracted from the gap around both of them, and the resin film is covered on the inner surface of the container body. A method for manufacturing an assembled paper container, comprising the steps of:

2. The method further includes a top seal attaching step of attaching a top seal to the resin film covering the upper surface of the flange portion above the upper surface of the flange portion, after the step reducing / resin film covering step, while pressing an upper portion of the step and crossing the step. The method for manufacturing the assembled paper container according to claim 1,

3. A manufacturing device for an assembled paper container, comprising: a container body having a storage section assembled from blank sheets mainly made of paper; and a resin film covering the inner surface of the container body, A lower mold on which the container body is placed; a suction covering section provided in the lower mold for sucking air between the resin film and the container body so as to cover the resin film on the inner surface of the container body; an upper mold that faces the lower mold and has the resin film sandwiched between the lower mold and an upper mold; a flange pressing portion that is accommodated in the upper mold and presses the flange portion of the container body and the resin film on the flange portion; a step reducing recess provided in the lower mold below the flange pressing portion of the upper mold; Equipped with When the resin film is placed and the surface of the region of the resin film that crosses the step of the flange portion of the container body is sucked by the suction covering portion, the edge of the upper folded piece that constitutes the step is pressed together with the lower folded piece via the flange pressing portion toward the step reducing recess that is disposed on the side of the lower folded piece and has a width equal to or greater than the length between the edges of the upper folded piece, thereby causing the lower folded piece to bulge downward in the region that contacts the upper folded piece and reducing the step. An apparatus for manufacturing assembled paper containers, comprising:

4. A manufacturing apparatus for an assembled paper container, which covers the containing portion by attaching a top seal to the resin film covering an upper surface of a flange portion in an assembled paper container manufactured by the manufacturing apparatus for an assembled paper container according to claim 3, A seal head disposed above the top seal; a seal bucket disposed below the assembled paper container; The seal bucket upper portion is made of an elastic member, The lower part of the seal bucket is made of a hard material. An apparatus for manufacturing assembled paper containers, comprising:

Images