Assembled paper container

Abstract

Provided is an assembled paper container capable of suppressing leakage or seepage of contents from a storage portion of a container body. An assembled paper container (1) of one embodiment includes a container body (11) and a resin film (3). The container body (11) has a storage portion (12). The container body (11) has a bottom surface (121), a plurality of side surfaces (122), and a flange portion (13) connected to the plurality of side surfaces (122) and having an upper surface (131) flush with the plurality of side surfaces (122) after assembly. The upper surface (131) has a gap (22) extending from the storage portion (12) toward the outside of the container body (11). The resin film (3) covers the upper surface (131) and has a protruding portion (31) that spans the gap (22) above the gap (22).

Description

[0001] This application is a divisional application of the invention patent application with application number 202080066913.7 (international application number PCT / JP2020 / 033074), application date September 1, 2020, and invention title "Assembled Paper Container and Film Adhesion Molding Machine". Technical Field

[0002] Embodiments of the present invention relate to an assembly paper container and a film bonding molding machine. Background Technology

[0003] Assembled paper containers are known to consist of a tray-shaped container body assembled from paper blanks, primarily made of paper, with a flange at the top. In these assembled paper containers, a resinous thermoplastic resin film is sometimes adhered to the inner surface of the container body and the upper surface of the flange (Patent Document 1 and Patent Document 2). Assembled paper containers with resin films are primarily used as trays or bowls for storing food due to their resinous nature.

[0004] Furthermore, compared to plastic containers, assembled paper containers can suppress the generation of secondary microplastics in the environment, making them environmentally friendly products. Moreover, the resin film can be peeled off from the container body, allowing for the separation of the resin film and the container body (paper), and enabling the recycling of both. Based on these advantages, it is anticipated that MAP (Modified Atmosphere Packaging) technology can be applied to assembled paper containers for use as packaging and preservation containers for food products.

[0005] Existing technical documents

[0006] Patent documents

[0007] Patent Document 1: Japanese Patent Application Publication No. 6-293334

[0008] Patent Document 2: Japanese Patent Application Publication No. 2019-172339 Summary of the Invention

[0009] The problem that the invention aims to solve

[0010] In the container body of an assembled paper container, due to its molding process, gaps are formed on the upper surface of the flange where the end faces of the blanks approach each other. Currently, even when using a resin film to cover the inner surface of the container body and the upper surface of the flange, it is difficult to completely fill these gaps. The resin film is thin. When the resin film is adhered to the assembled paper container by means of, for example, vacuum compression, the resin film is drawn into the gaps. It is difficult to seal the gaps with just the resin film.

[0011] A packaging method (e.g., MAP) has been developed that replaces the air in the storage section of the container body with a food gas suitable for food. When this packaging method is applied to an assembled paper container with a resin film, a top seal is adhered to the resin film on the upper surface of the flange. However, the top seal is also thin. Therefore, even when the top seal is adhered to the resin film, a void along the gap is created between the upper surface of the resin film and the lower surface of the top seal. Even with the top seal, it is difficult to completely seal the void. Moreover, both ends of the void are open. The storage section of the container body communicates with the outside of the container body through the void.

[0012] Based on the above, even if the top seal is used to cover the storage section in an assembled paper container with a resin film, it is still possible for the contents to leak or seep out through the holes in the storage section.

[0013] Embodiments of the present invention provide an assembled paper container capable of preventing leakage or seepage of the contents from the storage portion of the container body, and a film bonding molding machine capable of manufacturing the assembled paper container.

[0014] Methods for solving problems

[0015] The first embodiment of the present invention provides an assembled paper container comprising: a container body assembled from blanks primarily made of paper, having a receiving portion; and a resinous film covering the inner surface of the receiving portion, characterized in that the container body comprises: a bottom surface; a plurality of side surfaces rising from the bottom surface; and a flange portion connected to the plurality of side surfaces, the upper surface of the flange portion being flush with the upper surface of the flange portion after assembly, the upper surface of the flange portion having a gap created by the end faces of the blanks approaching each other, the gap extending from the receiving portion toward the outer side of the container body, the resinous film covering the upper surface of the flange portion, and a protrusion spanning the gap above the gap.

[0016] The second embodiment of the assembled paper container of the present invention is based on the first embodiment, characterized in that the protrusion has at least one corner spanning the gap above the gap.

[0017] The assembled paper container of the third aspect of the present invention is based on the first or second aspect, characterized in that the assembled paper container further comprises a top seal, which is adhered to the resinous film on the upper surface of the flange portion, covering the receiving portion, wherein the top seal flattens the protrusion above the upper surface of the flange portion and is adhered to the resinous film across the gap.

[0018] The fourth embodiment of the assembled paper container of the present invention is based on the third embodiment, characterized in that the resinous film is folded into at least three layers within the gap.

[0019] A fifth aspect of the present invention provides a film bonding and forming machine for bonding a resinous film to an assembled paper container with a flange. The film bonding and forming machine comprises: a lower mold on which the assembled paper container is placed; a bonding section disposed on the lower mold, which attracts the resinous film across the assembled paper container placed on the lower mold and bonds the resinous film to the assembled paper container; an upper mold opposite the lower mold, which holds the resinous film between the upper mold and the lower mold; a pressing machine housed in the upper mold, having a presser for pressing the resinous film placed on the flange; and a forming section disposed on the pressing machine, which attracts the resinous film placed on the flange and forms a protrusion on the resinous film that protrudes relative to the flange.

[0020] The sixth aspect of the film bonding molding machine of the present invention is based on the fifth aspect, characterized in that the attraction direction of the molding part is opposite to the attraction direction of the bonding part.

[0021] The film bonding molding machine of the seventh aspect of the present invention is based on the fifth or sixth aspect, characterized in that the attraction timing of the molding part is earlier than the attraction timing of the bonding part.

[0022] Invention Effects

[0023] In the assembled paper containers of embodiments 1 to 4, the resinous film covering the upper surface of the flange has a protrusion spanning the gap above the gap. Therefore, a top seal can be adhered to the resinous film above the gap to cover the open openings at both ends. Thus, the assembled paper containers of embodiments 1 to 4 provide an assembled paper container capable of preventing leakage or seepage of the contents from the storage portion of the container body.

[0024] The film bonding molding machine of embodiments 5 to 7 has a forming section that attracts a resinous film disposed on a flange portion and forms a protrusion on the resinous film that protrudes relative to the flange portion. Therefore, according to the film bonding molding machine of embodiments 5 to 7, it is possible to provide a film bonding molding machine capable of manufacturing assembled paper containers of embodiments 1 to 4. Attached Figure Description

[0025] Figure 1 (a) is a top view showing an example of an assembled paper container according to one embodiment.

[0026] Figure 1(b) is a side view showing an example of an assembled paper container according to one embodiment.

[0027] Figure 1 (c) is a perspective view showing an example of an assembled paper container according to one embodiment.

[0028] Figure 2 This is a top view showing an example of a blank.

[0029] Figure 3 (a)~ Figure 3 (d) is a schematic cross-sectional view showing an example of a protrusion.

[0030] Figure 4 This is a top view showing an example of using a top seal to cover the storage section.

[0031] Figure 5 (a)~ Figure 5 (d) is a schematic cross-sectional view showing how the top seal is attached to the resinous film.

[0032] Figure 6 (a)~ Figure 6 (d) is a schematic cross-sectional view showing how the top seal is attached to the resinous film.

[0033] Figure 7 (a) and Figure 7 (b) is a schematic cross-sectional view showing an example of a film bonding molding machine.

[0034] Figure 8 (a) and Figure 8 (b) is a schematic cross-sectional view showing how the protrusion is formed.

[0035] Figure 9 This is a schematic block diagram illustrating an example of a film bonding system.

[0036] Figure 10 (a) and Figure 10 (b) is a schematic cross-sectional view showing an example of the protrusion in the first modified example.

[0037] Figure 11 (a) and Figure 11 (b) is a schematic cross-sectional view showing an example of the protrusion in the second modified example.

[0038] Figure 12 (a) and Figure 12 (b) is a schematic cross-sectional view showing an example of the protrusion in the third modified example.

[0039] Figure 13 (a) and Figure 13(b) is a schematic cross-sectional view showing an example of the protrusion in the fourth modified example.

[0040] Figure 14 (a) and Figure 14 (b) is a schematic cross-sectional view showing an example of the protrusion in the fifth modified example.

[0041] Figure 15 (a) and Figure 15 (b) is a schematic cross-sectional view showing an example of the protrusion in the sixth modified example. Detailed Implementation

[0042] Hereinafter, one embodiment of the present invention will be described with reference to the accompanying drawings. In the drawings, common parts are labeled with common reference numerals, and repeated descriptions are omitted.

[0043] (Assembled paper containers)

[0044] Figure 1 (a) is a top view showing an example of an assembled paper container according to one embodiment. Figure 1 (b) is a side view showing an example of an assembled paper container according to one embodiment. Figure 1 (c) is a perspective view showing an example of an assembled paper container according to one embodiment. Figure 2 This is a top view showing an example of a blank.

[0045] Figure 1 (a)~ Figure 1 The assembled paper container 1 shown in (c) is from Figure 2 The blank 2 shown is assembled from paper. Blank 2 is primarily made of paper. Figure 2 In the diagram, dashed lines represent "valley folds," and single-dot dashed lines represent "peak folds." Valley fold lines and peak fold lines are formed, for example, by perforation lines, half-cuts, and grid lines. Additionally, thick solid lines represent "cut marks." An assembled paper container 1 is obtained by applying "valley folds" and "peak folds" to the blank sheet 2.

[0046] The assembled paper container 1 includes a container body 11 and a resinous film 3. The container body 11 includes a receiving portion 12 and a flange portion 13. The container body 11 has a bottom surface 121 and multiple side surfaces 122 rising from the bottom surface 121. The receiving portion 12 is composed of the bottom surface 121 and the multiple side surfaces 122. In this embodiment, there are eight side surfaces 122. Having three or more side surfaces 122 is sufficient to constitute the receiving portion 12.

[0047] The flange portion 13 is connected to the upper end of each side surface 122 in a manner extending outward from the receiving portion 12. The flange portion 13 has an upper surface 131. The upper surface 131 of the flange portion 13 is flush after assembly. A gap 22 is provided on the upper surface 131 of the flange portion 13. The gap 22 is generated on the upper surface 131 due to the end faces 21 of the assembled blank 2 approaching each other. The gap 22 extends outward from the receiving portion 12 toward the outer side of the container body 11. In this embodiment, an example is shown where the gap 22 is generated at the four corners of the flange portion 13.

[0048] A resinous film 3 covers the inner surface of the receiving portion 12, the inner surface of the side surface 122, and the upper surface 131 of the flange portion 13. The resinous film 3 is, for example, a resinous film with watertightness and gas desorption properties. Furthermore, an example of the resinous film 3 is a thermoplastic resin film. The resinous film 3 has a protrusion 31 above the gap 22. The protrusion 31 spans the gap 22. In this embodiment, there are four gaps 22. There are also four protrusions 31. Each of the four protrusions 31 is provided above one of the four gaps 22. Multiple protrusions 31 may also be provided for one gap 22. Figure 1 When observing the cross section of line IIIB-IIIB in (a), the shape of the protrusion 31 can be any shape, such as a semi-circular shape, a quadrilateral shape, or a triangular shape.

[0049] Figure 3 (a)~ Figure 3 (d) is a schematic cross-sectional view showing an example of a protrusion. Figure 3 The section shown in (a) is along Figure 1 Lines IIIA-IIIA in (a). Figure 3 The section shown in (b) is along Figure 1 Line IIIB-IIIB in (a). Figure 3 The section shown in (c) is along Figure 1 The IIIC-IIIC line in (a). Figure 3 The section shown in (d) is along Figure 1 The IIID-IIID line in (a).

[0050] like Figure 3 (a)~ Figure 3 As shown in (d), the resinous film 3 is embedded in the gap 22. However, the protrusion 31 protrudes upward from the flange 13 above the gap 22.

[0051] Furthermore, examples of resinous films 3 capable of forming protrusions 31 include polyolefins such as polyethylene (PE) and polypropylene (PP), polyesters such as polyvinyl chloride and polyethylene terephthalate (PET), ethylene-vinyl acetate copolymer (EVA), ethylene-acrylic acid copolymer, polyamide, polyvinylidene chloride, polystyrene, polycarbonate, polybutene, and polyvinyl alcohol. The resinous film 3 can be a single film of any of the above materials, or it can be a film composed of a mixture of multiple of the above materials. Additionally, the resinous film 3 can be a single-layer film or a multi-layered film.

[0052] Figure 4 This is a top view showing an example of a storage section covered by a top seal.

[0053] like Figure 4 As shown, the assembled paper container 1 can package and store food and the like by covering the storage portion 12 with a top seal 4. The top seal 4 is adhered to a resinous film 3 on the upper surface 131 of the flange portion 13. Thus, the top seal 4 covers the storage portion 12. In this embodiment, the top seal 4 spans the gap 22 above the upper surface 131 of the flange portion 13, flattens the protrusion 31, and adheres to the resinous film 3. When the top seal 4 is adhered to the resinous film 3, the top seal 4 is pressed by a presser (e.g., a sealing head) of a presser. The presser presses the top seal 4 in the area shown in the pressing area 32. In this embodiment, the protrusion 31 is configured such that the entire protrusion 31 is incorporated within the width of the pressing area 32. Thus, the protrusion 31 can be reliably flattened by the presser.

[0054] <Top Seal Adhesion: Example Reference>

[0055] As a reference example of the present invention, Figure 5 (a)~ Figure 5 (d) shows an example where the protrusion 31 is not formed.

[0056] Figure 5 (a)~ Figure 5 (d) is a schematic cross-sectional view showing how the top seal is attached to the resinous film. Figure 5 (a)~ Figure 5 The cross sections shown in (d) are respectively with Figure 3 The cross section shown in (b) is equivalent.

[0057] like Figure 5 As shown in (a), a resinous film 3 is placed on the upper surface 131 of the flange portion 13.

[0058] Next, as Figure 5As shown in (b), the resinous film 3 is attracted through the container body 11, for example, by vacuum compression. The container body 11 is mainly made of paper. Therefore, by attraction, the resinous film 3 adheres tightly to the flange portion 13. At this time, the resinous film 3 is attracted into the gap 22 and becomes embedded in the gap 22.

[0059] Then, as Figure 5 As shown in (c), the heated top seal 4 is placed on the resinous film 3.

[0060] Next, as Figure 5 As shown in (d), the heated top seal 4 is pressed by a presser, heat-pressing it onto the upper surface 33 of the resin film 3. However, since the resin film 3 is pressed into the gap 22, the lower surface 41 of the top seal 4 does not reach the upper surface 33 of the resin film 3 within the gap 22. Therefore, a cavity 5 is formed between the upper surface 33 of the resin film 3 and the lower surface 41 of the top seal 4. Since both ends of the cavity 5 are open, the receiving part 12 communicates with the outside of the container body 11 through the cavity 5.

[0061] If a hole 5 is formed, even if the top seal 4 is used to cover the storage section 12, the stored items may leak or seep out of the storage section 12 through the hole 5.

[0062] <Top seal adhesive>

[0063] Figure 6 (a)~ Figure 6 (d) is a schematic cross-sectional view showing how the top seal is attached to the resinous film. Figure 6 (a)~ Figure 6 The cross section shown in (d) is... Figure 3 The cross section shown in (b) is equivalent.

[0064] like Figure 6 As shown in (a), a resinous film 3 is placed on the upper surface 131 of the flange portion 13.

[0065] Next, as Figure 6 As shown in (b), the resinous film 3 is attracted through the assembled paper container 1, for example, by vacuum compression. The resinous film 3 is then pressed tightly against the upper surface 131 of the flange portion 13. In this embodiment, the resinous film 3 is also attracted into the gap 22 and embedded within it. However, the protrusion 31 remains in a state where it protrudes upwards into the gap 22 and extends beyond the upper surface 33 of the resinous film 3 on the upper surface 131 of the flange portion 13. Furthermore, an example of the molded protrusion 31 will be described later.

[0066] Then, as Figure 6As shown in (c), the heated top seal 4 is placed on the resinous film 3.

[0067] Next, as Figure 6 As shown in (d), the heated top seal 4 is pressed using a press machine. The top seal 4 is then heat-pressed onto the upper surface 33 of the resin film 3. Therefore, the upper surface of the resin film 3 is in contact with the lower surface 41 of the top seal 4.

[0068] Furthermore, during the heat-pressing process, the protrusion 31 is flattened by pressing the top seal 4 with a presser. Since the protrusion 31 spans the gap 22, it is flattened across the gap 22. A portion of the protrusion 31 forms part of the upper surface 33 of the resinous film 3. In this embodiment, as... Figure 6 As shown in (b), the protrusion 31 has a first corner 31a that spans the gap 22 above the gap 22. The cross-section of the protrusion 31 along the direction of the gap 22 is triangular. The inclined surface 312 of the triangle becomes the upper surface 33 of the resin film 3 as the protrusion 31 is gradually flattened. Therefore, the upper surface of the resin film 3 spans the gap 22 and contacts the lower surface 41 of the top seal 4.

[0069] According to this embodiment, the top seal 4 can be heat-pressed onto the upper surface 33 of the resin film 3 even above the gap 22. That is, the top seal 4 can be adhered to the upper surface of the resin film 3 above the gap 22 in a manner that covers the hole 5.

[0070] Furthermore, the flattening of the protrusion 31 results in the folding of the sidewall 34 of the protrusion 31 of the resinous film 3, at least in the gap 22, into multiple layers. For example, in Figure 6 In one example shown in (d), the resin film 3 is folded into three layers, but the resin film 3 can also be folded into more than three layers, for example, in a serpentine shape. By folding the resin film 3 into multiple layers at least within the gap 22, the top seal 4 can be easily heat-pressed onto the upper surface 33 of the resin film 3, even above the gap 22. The multi-layered resin film 3 exerts a reaction force on the top seal 4 during pressing.

[0071] And, as Figure 6 As shown in (b), the protrusion 31 has a first corner portion 31a. When the protrusion 31 has a first corner portion 31a, compared to, for example, when the protrusion 31 does not have a corner portion 31a, it is easier to flatten. In addition, the first corner portion 31a can be not only angular, but also smooth, such as a rounded shape.

[0072] Thus, according to one embodiment, the cavity 5 can be covered by the resinous film 3 and the top seal 4, an assembled paper container 1 that can suppress leakage or seepage of the contents from the storage portion 12 of the container body 11 can be provided.

[0073] (Film pasting and forming machine)

[0074] Figure 7 (a) and Figure 7 (b) is a schematic cross-sectional view showing an example of a film bonding molding machine.

[0075] The film bonding molding machine 600 is a novel molding machine capable of manufacturing an assembled paper container 1 according to one embodiment. The film bonding molding machine 600 bonds a resinous film 3 to the assembled paper container 1 with a flange portion 13. Furthermore, the film bonding molding machine 600 forms protrusions 31 on the resinous film 3 during bonding.

[0076] like Figure 7 (a) and Figure 7 As shown in (b), the film pasting molding machine 600 includes a lower mold 610, a pasting part 611, an upper mold 620, a flange pressing part 630, and a molding part 631.

[0077] An assembled paper container 1 is placed on the lower mold 610.

[0078] An adhesive part 611 is disposed on the lower mold 610. The adhesive part 611 is connected to a vacuum pump 640. The adhesive part 611 attracts the resinous film 3 through the assembled paper container 1 placed on the lower mold 610.

[0079] The upper mold 620 and the lower mold 610 are opposed to each other. The upper mold 620 is, for example, capable of moving up and down. The resin film 3 is sandwiched between the lower mold 610 and the upper mold 620. When the upper mold 620 and the lower mold 610 are tightly attached such that the resin film 3 is sandwiched between them, a substantially sealed processing space is formed. In the processing space, the resin film 3 is adhered to the receiving portion 12 and the flange portion 13, for example, by vacuum compression.

[0080] The flange pressing portion 630 is housed within the upper mold 620. The flange pressing portion 630 is supported on the top plate portion 621 of the upper mold 620 by a retractable elastic member 632. An example of the elastic member 632 is a spring. The flange pressing portion 630 presses the flange portion 13 and the resinous film 3 on the flange portion 13, for example, during vacuum compression.

[0081] A forming part 631 is provided on the flange pressing part 630. The forming part 631 is connected to the vacuum pump 640. The forming part 631 attracts the protrusion forming area of ​​the resin film 3 on the flange part 13. The protrusion forming area is set to span the gap 22. The formation of the protrusion 31 is performed, for example, during the pasting of the resin film 3 to the receiving part 12 and the flange part 13. The attraction direction of the forming part 631 is opposite to the attraction direction of the pasting part 611. In this embodiment, the pasting part 611 attracts the resin film 3 toward the assembled paper container 1. The forming part 631 attracts the resin film 3 away from the assembled paper container 1.

[0082] Figure 8 (a) and Figure 8 (b) is a schematic cross-sectional view showing the shape of the protrusion 31.

[0083] like Figure 8 (a) and Figure 8 As shown in (b), when the protrusion 31 is formed by suction, the thickness T of the resinous film 3 changes before and after suction. For example, after suction, the thickness T of the resinous film 3 of the protrusion 31 becomes thinner. When the thickness T of the resinous film 3 of the protrusion 31 becomes thinner, the protrusion 31 is easier to fold or flatten compared to when it is thicker. This is one of the advantages of forming the protrusion 31 by suction of the resinous film 3.

[0084] (Example of the operation of a film bonding and forming machine)

[0085] like Figure 7 (a) and Figure 7 As shown in (b), with the upper mold 620 and the lower mold 610 separated, the heated resin film 3 is introduced between the upper mold 620 and the lower mold 610.

[0086] Next, the assembled paper container 1 is placed on the lower mold 610.

[0087] Then, the upper mold 620 is lowered to press the resin film 3. Furthermore, the flange pressing part 630 is used to press the flange part 13 and the resin film 3 on the flange part 13.

[0088] Next, the resin film 3 is attracted by the adhesive part 611 and the molding part 631 respectively. As a result, the resin film 3 is adhered to the bottom surface 121 of the storage part 12, the side surface 122 of the storage part 12, and the upper surface 131 of the flange part 13 respectively. Furthermore, a protrusion 31 protruding from the flange part 13 is formed above the gap 22 on the flange part 13.

[0089] Furthermore, the suction timing of the molding portion 631 can be earlier than that of the adhesive portion 611. With such staggered suction timing, the protrusion 31 can be formed before the resin film 3 is adhered to the upper surface 131 of the flange portion 13. Therefore, the advantage of easy forming of the protrusion 31 can be obtained.

[0090] Next, the upper mold 620 is raised. Then, the assembled paper container 1, along with the resin film 3, is removed from the film bonding molding machine.

[0091] Thus, the film bonding and molding machine 600 can manufacture assembled paper containers 1.

[0092] (Film bonding system)

[0093] Figure 9 This is a schematic block diagram illustrating an example of a film bonding system.

[0094] The film bonding system 700 uses a take-up roller 720 to take up the resin film 3 wound on the supply roller 710 and then bonds the resin film 3 to the assembled paper container 1 with the flange portion 13.

[0095] like Figure 9 As shown, the film bonding system 700 includes a supply roller 710, a take-up roller 720, a heater 730, a film bonding forming machine 600, and a cutting machine 740.

[0096] A strip of resinous film 3 is wound on the feed roller 710.

[0097] One end of a strip of resinous film 3 is mounted on a take-up roller 720. The take-up roller 720 takes up the strip of resinous film 3. The strip of resinous film 3 moves from the feed roller 710 toward the take-up roller 720 along the conveying direction W.

[0098] The heating unit 730 is positioned between the supply roller 710 and the take-up roller 720. The heating unit 730 heats the strip-shaped resinous film 3.

[0099] The film bonding forming machine 600 is configured between the heating unit 730 and the take-up roller 720. The film bonding forming machine 600 is, for example, the film bonding forming machine described above.

[0100] A cutting machine 740 is positioned between a film bonding and forming machine 600 and a take-up roller 720. The cutting machine 740 cuts the assembled paper container 1, which is adhered to the strip of resin film 3, from the strip of resin film 3. As a result, the assembled paper container 1 is detached from the strip of resin film 3.

[0101] Thus, the film bonding system 700 includes a film bonding forming machine 600. Therefore, according to the film bonding system 700, it is possible to manufacture assembled paper containers 1. Moreover, according to the film bonding system 700, it is possible to continuously manufacture assembled paper containers 1 from strip-shaped resinous films 3.

[0102] (A modified example of protrusion 31)

[0103] Next, several variations of the protrusion 31 will be explained.

[0104] <First Variation>

[0105] Figure 10 (a) and Figure 10 (b) is a schematic cross-sectional view showing an example of the protrusion in the first modified example. Figure 10 The schematic cross-section shown in (a) illustrates the area before the top seal is applied. Figure 10 The schematic cross section shown in (b) illustrates the application of the top seal.

[0106] like Figure 10 (a) and Figure 10 As shown in (b), the protrusion 31 may also have two corners, a first corner 31a and a second corner 31b, above the gap 22. The cross-section of the protrusion 31 along the direction of the gap 22 is quadrilateral. In the first modified example, the upper surface 313 of the quadrilateral becomes the upper surface 33 of the resin film 3 as the protrusion 31 is gradually flattened.

[0107] In the first modified example, the upper surface of the resin film 3 can also cross the gap 22 and contact the lower surface 41 of the top seal 4. Thus, the cavity 5 can be covered by the resin film 3 and the top seal 4.

[0108] Therefore, according to the first modification, an assembled paper container 1 can be provided that can suppress leakage or seepage of the contents from the storage portion 12 of the container body 11.

[0109] <Second Variation>

[0110] Figure 11 (a) and Figure 11 (b) is a schematic cross-sectional view showing an example of the protrusion in the second modified example. Figure 11 The schematic cross-section shown in (a) illustrates the area before the top seal is applied. Figure 11 The schematic cross section shown in (b) illustrates the application of the top seal.

[0111] like Figure 11 (a) and Figure 11As shown in (b), the cross-section of the protrusion 31 along the direction of the gap 22 can also be trapezoidal. In the second variation, the upper surface 314 of the trapezoid becomes the upper surface 33 of the resin film 3 as the protrusion 31 is gradually flattened.

[0112] In the second variation, an assembled paper container 1 capable of preventing leakage or seepage of the contents from the storage portion 12 of the container body 11 can also be provided.

[0113] <3rd Variation>

[0114] Figure 12 (a) and Figure 12 (b) is a schematic cross-sectional view showing an example of the protrusion in the third modified example. Figure 12 The schematic cross-section shown in (a) illustrates the area before the top seal is applied. Figure 12 The schematic cross section shown in (b) illustrates the application of the top seal.

[0115] like Figure 12 (a) and Figure 12 As shown in (b), the cross-section of the protrusion 31 along the direction of the gap 22 can also be a combination of two triangles. In the third variation, the inclined surface 315 of the first triangle and the inclined surface 316 of the second triangle face each other, forming a so-called M-shape. In the third variation, the protrusion 31 has a first corner 31a, a second corner 31b, and a third corner 31c above the gap 22. In the third variation, the inclined surfaces 315 and 316 of the first and second triangles both become the upper surface 33 of the resinous film 3 as the protrusion 31 is gradually flattened.

[0116] In the third variation, an assembled paper container 1 capable of preventing leakage or seepage of the contents from the storage section 12 of the container body 11 can also be provided.

[0117] Furthermore, in the third modification, the inclined surfaces 315 of the first triangle and 316 of the second triangle both become the upper surface 33 of the resinous film 3. Therefore, it is easy to increase the contact area between the top seal 4 and the upper surface 33 of the resinous film 3 above the gap 22. Thus, according to the third modification, it is possible to further improve the effect of concealing the void 5.

[0118] <4th Variation>

[0119] Figure 13 (a) and Figure 13 (b) is a schematic cross-sectional view showing an example of the protrusion 31 in the fourth modified example. Figure 13 The schematic cross-section shown in (a) illustrates the area before the top seal 4 is attached. Figure 13The schematic cross-section shown in (b) illustrates the application of the top seal 4 after it has been attached.

[0120] like Figure 13 (a) and Figure 13 As shown in (b), when the cross-section of the protrusion 31 along the direction of the gap 22 is M-shaped, the first triangular portion and the second triangular portion can also be formed to the middle of the protrusion 31.

[0121] In the fourth variation, an assembled paper container 1 is also provided that can prevent the contents from leaking or seeping out of the storage section 12 of the container body 11.

[0122] <5th Variation>

[0123] Figure 14 (a) and Figure 14 (b) is a schematic cross-sectional view showing an example of the protrusion in the fifth modified example.

[0124] like Figure 14 (a) and Figure 14 As shown in (b), for example in the first variation, the first corner portion 31a and the second corner portion 31b can be not only angular shapes, but also smooth shapes, such as rounded shapes as shown in the figure. Furthermore, regarding the first corner portion 31a of the above embodiment (for example, refer to...), Figure 6 (b)), the first corner 31a and the second corner 31b of the second variation (for example, refer to...) Figure 11 (a) and the first corner 31a to the third corner 31c of the third variation (for example, refer to...) Figure 12 (a) and the first corner 31a to the third corner 31c of the fourth variation (for example, refer to...) Figure 13 The same applies to (a).

[0125] <Sixth Variation>

[0126] Figure 15 (a) and Figure 15 (b) is a schematic cross-sectional view showing an example of the protrusion in the sixth modified example.

[0127] like Figure 15 (a) and Figure 15 As shown in (b), the front end face 317 of the protrusion 31 can also be rounded all the way. For example, even if the front end face 317 is rounded all the way, the protrusion 31 can be flattened into, for example, a serpentine shape. Therefore, in the sixth modification, the upper surface 33 of the resinous film 3 can also be pressed against the top seal 4.

[0128] The present invention has been described above as an embodiment, but this embodiment is provided as an example and is not intended to limit the scope of the invention. Furthermore, the above embodiment is not the only one. The present invention can be implemented in various new ways besides the above embodiment. Therefore, the above embodiment can be subject to various omissions, substitutions, and modifications without departing from the spirit of the invention. Such new methods and modifications are included within the scope and spirit of the present invention, and are included within the scope of the invention described in the claims and its equivalents.

[0129] Label Explanation

[0130] 1: Assembled paper container; 11: Container body; 12: Storage section; 121: Bottom surface; 122: Side surface; 13: Flange; 131: Top surface; 2: Blank sheet; 21: End face; 22: Gap; 3: Resin film; 31: Protrusion; 31a: First corner; 31b: Second corner; 31c: Third corner; 312: Triangular slope; 313: Quadrilateral top surface; 314: Trapezoid top surface; 315: First triangular slope; 316: Second triangular slope; 317: Protrusion 32: Front end face of the part; 33: Pressing area; 34: Upper surface; 4: Side wall; 5: Top seal; 61: Lower surface; 62: Hole; 600: Film pasting forming machine; 610: Lower mold; 611: Pasting part; 620: Upper mold; 621: Top plate part; 630: Flange pressing part; 631: Forming part; 632: Elastic component; 640: Vacuum pump; 700: Film pasting system; 710: Supply roller; 720: Take-up roller; 730: Heating machine; 740: Cutting machine; T: Thickness; W: Feed direction.

Claims

1. An assembled paper container, comprising: a container body assembled from paper-based blanks, having a storage portion; and a resin film covering the inner surface of the storage portion, characterized in that... The container body has: bottom surface; Multiple sides, which rise from the bottom surface; A flange portion, which connects to the plurality of side surfaces, is flush with the upper surface of the flange portion after assembly; and A top seal is attached to the resin film on the upper surface of the flange portion, thus covering the receiving portion. The upper surface of the flange portion has a gap created by the end faces of the blanks approaching each other, and this gap extends from the receiving portion toward the outer side of the container body. The resin film covers the upper surface of the flange, and above the gap, there is a protrusion that spans the gap and protrudes from the resin film. The top seal flattens the protrusion above the upper surface of the flange and is adhered to the resin film across the gap.

2. The assembled paper container according to claim 1, characterized in that, The resin film is folded into at least three layers within the gap.

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