Cuplike container

Abstract

To provide a cuplike container excellent in sealability of a joint formed in a trunk and capable of surely preventing leakage of a content as a container inexpensively manufactured using a paper cup manufacturing facility, excellent in long content storage performance, and capable of aseptic sterilization and retort sterilization.SOLUTION: This cuplike container is constructed such that a trunk bland 20A is formed by a laminate 20 composed of a metal foil layer 201 and heat-sealable resin layers 202 and 203 layered on both surfaces of the metal foil layer 201. A tape-like seal material 4 is jointed to the inner surface of a trunk 2 so as to cover a joint 211 of both end edges 204 and 205 of the trunk bland 20A. The tape-like seal material 4 has at least the inner surface and the joint surface side of the trunk formed by heat-sealable resins, and is heat-sealed to the inner surface of the trunk 2. In the trunk bland 20A, metal foil constituting the metal foil layer 201 and films constituting the heat-sealable resin layers 202 and 203 are layered via the adhesive layers.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to a cup-shaped container for containing food or beverages such as ice cream or yogurt. [Background technology]

[0002] 2. Description of the Related Art Paper cup-shaped containers, that is, paper cups, are commonly used as containers for filling and packaging semi-solid dairy products such as ice cream and yogurt. A paper cup is usually formed by joining together a body and a bottom, each of which is made of a paper blank cut to a predetermined shape. More specifically, the body is formed into a cylindrical shape by overlapping and joining both end edges of a substantially sector-shaped body blank, with a folded-back portion folded inward at the bottom opening edge and a flange portion curled outward at the top opening edge. The bottom has a substantially inverted U-shaped cross section, formed by skirt-molding a substantially circular bottom blank so that a hanging portion is formed on its outer periphery. The hanging portion of the bottom is wrapped around and joined to the folded-back portion of the body, thereby integrating the body and the bottom. Each blank for the body and bottom body is made of a laminate having, for example, a paper layer made of general base paper, acid-resistant paper, coated paper, etc., and a polyethylene (PE) layer laminated on one or both sides of the paper layer (see, for example, Patent Document 1 below).

[0003] Also known is a paper cup that uses a laminate formed by laminating a barrier layer made of aluminum foil or the like in addition to a paper layer and a polyethylene (PE) layer as the material for each of the above blanks (see, for example, Patent Document 2 below).

[0004] Additionally, containers for ice cream, yogurt, etc., made of plastic molded bodies such as polypropylene (PP) are also known (see, for example, Patent Document 3 below). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 58-30955 [Patent Document 2] JP 2007-210639 A [Patent Document 3] JP 2007-176505 A Summary of the Invention [Problem to be solved by the invention]

[0006] However, while paper cups have excellent productivity and can be manufactured at low cost, they have poor barrier properties and are not suitable for long-term storage of contents. Paper cups with a barrier layer such as aluminum foil improve the long-term storage of the contents, but water easily penetrates through the edges of the paper layer, making retort sterilization impossible. In addition, plastic containers are expensive to manufacture and are not suitable for long-term storage of the contents.

[0007] In order to solve the above problems, the present inventor previously proposed a cup-shaped container using a laminate consisting of a metal foil layer and a heat-fusible resin layer laminated on at least one of its two sides as the material for each of the body blank and the bottom blank (Patent Application No. 2019-106125). The above-mentioned cup-shaped container can be produced inexpensively using paper cup manufacturing equipment, has excellent long-term storage properties for the contents, and can also be subjected to aseptic sterilization or retort sterilization.

[0008] In the case of the above-mentioned cup-shaped container, a seam is formed between both end edges of the body blank in the body, and if the sealing property at this seam is insufficient, leakage of the contents may occur. The object of the present invention is to provide a cup-shaped container which can be produced inexpensively using paper cup production equipment, has excellent long-term storage properties for the contents, and can be subjected to aseptic sterilization or retort sterilization, has excellent sealing properties at the seams formed in the body, and can reliably prevent leakage of the contents. [Means for solving the problem]

[0009] In order to achieve the above object, the present invention comprises the following aspects.

[0010] 1) A cup-shaped container comprising a body formed into a cylindrical shape by overlapping and joining both end edges of a body blank, and a bottom body having a cross section of a generally inverted U-shape formed by forming a bottom body blank so as to form a bottom and a hanging part extending downward from the outer peripheral edge of the bottom body, the body and bottom body being integrated by joining the outer surface of the hanging part of the bottom body to the inner surface of the lower end of the body, the body blank is formed from a laminate consisting of a metal foil layer and a heat-sealable resin layer laminated on at least one of both sides of the metal foil layer that will become the inside of the body, the blank does not have a paper layer, and both end edges of the body blank are joined by heat-sealing the heat-sealable resin layers that constitute the mutually overlapping surfaces, The bottom body blank is formed from a laminate consisting of a metal foil layer and a heat-sealable resin layer laminated on at least one of both sides of the metal foil layer that will be the upper side of the bottom body, and the inner surface of the lower end of the body and the outer surface of the hanging part of the bottom body are joined by heat-sealing the heat-sealable resin layers that make up these surfaces, a tape-like sealing material is bonded to an inner surface of the body so as to cover a seam between both end edges of the body blank; At least the joining surface of the tape-shaped sealing material with the inner surface of the body is made of a heat-sealing resin and is heat-sealed to the inner surface of the body; A cup-shaped container, comprising a body blank in which a metal foil constituting a metal foil layer and a film constituting a heat-fusible resin layer are laminated via an adhesive layer.

[0011] 2) The cup-shaped container according to 1) above, wherein the adhesive constituting the adhesive layer is a two-component curing type polyester-polyurethane adhesive or polyether-polyurethane adhesive.

[0012] 3) The body blank is formed from a laminate consisting of a metal foil layer and a heat-fusible resin layer laminated on both sides of the metal foil layer, Both end edge portions of the fuselage blank are overlapped and joined by heat-sealing the heat-sealable resin layers constituting the mutually overlapping surfaces, A cup-shaped container according to 1) or 2) above, wherein the end faces of the inner end edges located on the inside of the body, of both end edges of the body blank, are covered with a tape-like sealing material.

[0013] 4) A cup-shaped container as described above in 3), in which the width of the portion of the tape-shaped sealing material that is joined to the inner surface of the inner edge portion located on the inside of the body, among the two end edges of the body blank, is made larger than the overlap width of the two end edges of the body blank.

[0014] 5) A flange portion bent outward is provided at the upper opening edge of the body, A cup-shaped container according to any one of 1) to 4) above, wherein the joints between both end edges of the body blank, excluding the portion for forming the flange portion, are covered with a tape-like sealing material.

[0015] 6) The body further has a folded-back portion that is folded inward from the lower end opening edge portion thereof so as to enclose the hanging portion of the bottom body and extend upward, The folded portion of the body and the hanging portion of the bottom body are joined by heat-sealing the heat-sealable resin layers constituting the overlapping surfaces of the folded portion and the hanging portion of the bottom body, A cup-shaped container according to any one of 1) to 5) above, wherein the seams between both end edges of the body blank, excluding the portion for forming the folded-back portion, are covered with a tape-like sealing material.

[0016] 7) A cup-shaped container according to any one of 1) to 4) above, in which only the portion of the seam between both end edges of the body blank that is located on the inner surface of the body is covered with a tape-like sealing material.

[0017] 8) A cup-shaped container according to any one of 1) to 7) above, in which the heat-sealing resin constituting at least the joining surface side of the tape-shaped sealing material with the inner surface of the body is the same or of the same type as the heat-sealing resin layer of the body blank that constitutes the inner surface of the body.

[0018] 9) A cup-shaped container according to any one of 1) to 8) above, in which the melt mass flow rate (MFR) of the heat-sealable resin constituting at least the joining surface side with the inner surface of the body of the tape-shaped sealing material is 1 to 20 g / 10 min. Effect of the Invention

[0019] According to the cup-shaped containers 1) to 9) above, a tape-like sealing material is joined to the inner surface of the body so as to cover the seam between both end edges of the body blank, thereby dramatically improving the sealing ability of the seam and reliably preventing leakage of the contents.

[0020] According to the cup-shaped container 3) above, the end face of the inner edge portion of the body blank is covered with a tape-shaped sealing material, so that the end face can be effectively prevented from being exposed to the contents and causing delamination or corrosion. Furthermore, in the case of the cup-shaped container 3) above, both end edges of the body blank are overlapped and joined, so even if a tape-shaped sealing material is joined to the inside surface of the body, the number of layers constituting the overlapping portion of the body is reduced, and processing such as forming a flange portion at the upper opening edge of the body and forming a folded-back portion at the lower opening edge of the body can be easily carried out without hindrance.

[0021] According to the cup-shaped containers of 1) to 9) above, the tape-like sealing material is reliably bonded to the inner surface of the body by heat fusion, so that excellent sealing properties can be obtained.

[0022] According to the cup-shaped container 8) above, the heat-sealing resin constituting at least the joining surface side of the tape-shaped sealing material with the inner surface of the body is the same or of the same type as the heat-sealing resin layer of the body blank that constitutes the inner surface of the body, so that the tape-shaped sealing material is firmly joined to the inner surface of the body, resulting in even better sealing properties.

[0023] According to the cup-shaped container of 9) above, at least the joint surface side of the tape-shaped sealing material that joins with the inner surface of the body is made of a heat-sealable resin having a melt mass flow rate (MFR) within the above range. Therefore, even if a gap occurs between the tape-shaped sealing material and the joint between both end edges of the body blank, the gap is filled by the heat-sealable resin that melts when the tape-shaped sealing material is heat-sealed to the inner surface of the body, so that the joint between both end edges of the body blank is more reliably covered. In the present invention, the term "melt mass flow rate (MFR)" refers to a value determined in accordance with the standard test method for MFR specified in JIS K7210-1-2014. For example, when the heat-fusible resin is polypropylene, its MFR is a value measured in accordance with the above test method under conditions of a temperature of 230°C and a load of 2.16 kgf. In addition, when the tape-shaped sealing material is composed of two or more heat-sealable resin layers, the "melt mass flow rate (MFR) of the heat-sealable resin constituting the tape-shaped sealing material" refers to the MFR of the heat-sealable resin layer on the seal side that is heat-sealed to the inner surface of the body. [Brief description of the drawings]

[0024] [Figure 1] 1 is a perspective view of a cup-shaped container according to a first embodiment of the present invention. [Diagram 2] This is a vertical cross-sectional view taken along line II-II in FIG. 1, in which the portion surrounded by dashed dotted line A is an enlarged view of the portion surrounded by dashed dotted line a, and the portion surrounded by dashed dotted line B is an enlarged view of the portion surrounded by dashed dotted line b. [Diagram 3]FIG. 2 is a vertical cross-sectional view taken along line III-III in FIG. [Figure 4] 1A is an enlarged cross-sectional view showing the layer structure of a laminate used as the material for the body blank, and FIG. 1B is an enlarged cross-sectional view showing the layer structure of a laminate used as the material for the bottom blank. [Diagram 5] 3 is a horizontal cross-sectional view showing an enlarged overlapping portion of the body of the cup-shaped container. FIG. [Figure 6] FIG. 1(a) is a plan view of a fuselage blank, FIG. 1(b) is an oblique view of a fuselage formed from the fuselage blank, and FIG. 1(c) and (d) are horizontal cross-sectional views sequentially showing the process of heat-sealing a tape-shaped sealing material to the inner surface of the fuselage. [Figure 7] 1A is a plan view of a bottom body blank, and FIG. 1B is a perspective view of a bottom body formed from the bottom body blank. [Figure 8] 5A to 5C are vertical cross-sectional views showing a part of the manufacturing process of the cup-shaped container. [Figure 9] FIG. 4 is a perspective view of a cup-shaped container according to a second embodiment of the present invention. [Figure 10] FIG. 10 is a horizontal cross-sectional view taken along line XX in FIG. [Figure 11] 11 is an enlarged horizontal cross-sectional view showing a portion surrounded by a dashed dotted line c in FIG. 10. [Figure 12] 1A and 1B are horizontal cross-sectional views sequentially showing the steps of forming a fuselage from a fuselage blank, and FIG. 1C and 1D are horizontal cross-sectional views sequentially showing the steps of heat-sealing a tape-shaped sealing material to the inner surface of the fuselage. [Figure 13] FIG. 12 is a horizontal cross-sectional view corresponding to FIG. 11, showing a main part of a cup-shaped container according to a third embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0025] Hereinafter, an embodiment of the present invention will be described with reference to FIGS. In the following explanation, "upper and lower" refers to the upper and lower sides of the cup-shaped container, body and bottom body (e.g., the upper and lower sides in Figures 2, 3 and 8), "inner" refers to the side closer to the center of the cup-shaped container, body and bottom body (e.g., the upper side in Figures 5, 11 and 13, and the right side in Figure 8), and "outer" refers to the side farther from the center of the cup-shaped container, body and bottom body (e.g., the lower side in Figures 5, 11 and 13, and the left side in Figure 8).

[0026] <First embodiment> Figures 1 to 3 show the overall structure of a cup-shaped container (1) according to a first embodiment of the present invention. The container (1) is formed by joining together a body (2) formed from a body blank (20A) and a bottom body (3) formed from a bottom body blank (30A). The body (2) is a tapered cylinder, and is formed by overlapping and joining both end edges (204), (205) of a generally sector-shaped body blank (20A) as shown in Fig. 6. Therefore, the body (2) has an overlap portion (21) that extends along its height direction. The body (2) has a folded-back portion (22) folded inward at the edge of the lower opening. The body 2 has an outwardly bent flange 23 at the upper opening edge. The flange 23 is folded downward and formed into a substantially horizontal flat shape. The flange may have a shape other than that shown in the figure, for example, it may be curled downward and formed into a substantially arc-shaped cross section. The bottom body (3) has a generally inverted U-shaped cross section, with a circular, horizontal bottom portion (31) and a hanging portion (32) extending downward from the outer peripheral edge of the bottom portion (31), and is formed by drawing a circular bottom body blank (30A) as shown in Figure 7. The outer surface of the hanging portion (32) of the bottom body (3) is joined to the inner surface of the lower end portion (2a) of the body (2), and the folded portion (22) of the body (2) is joined to the inner surface of the hanging portion (32), thereby integrating the body (2) and the bottom body (3) (see Figures 2, 3 and 8). Although not shown in the figures, the body (2) and the bottom body (3) can be integrated by a connecting structure in which the outer surface of the hanging portion (32) of the bottom body (3) is joined to the inner surface of the lower end (2a) of the body (2) without forming a folded portion (22) at the edge of the lower end opening of the body (2). With this configuration, even if some wrinkles are generated in the hanging portion (32) when the bottom body (3) is molded, the lower end (2a) of the body (2) and the hanging portion (32) of the bottom body (3) can be reliably sealed without mixing in air or the like.

[0027] As shown in FIG. 4(a), the body blank (20A) is formed from a laminate (20) comprising a metal foil layer (201), an inner heat-sealable resin layer (202) laminated on one of both sides of the metal foil layer (201) that will be on the inside of the body (2), and an outer heat-sealable resin layer (203) laminated on one of both sides of the metal foil layer (201) that will be on the outside of the body (2), and does not have a paper layer. As shown in Fig. 4(b), the bottom blank (30A) is also formed of a laminate (30) consisting of a metal foil layer (301), an upper heat-sealable resin layer (302) laminated on one of both sides of the metal foil layer (301) that is the upper side of the bottom body (3), and a lower heat-sealable resin layer (303) laminated on one of both sides of the metal foil layer (301) that is the lower side of the bottom body (3), and does not have a paper layer. Note that if the folded portion (22) is not formed at the edge of the lower end opening of the body (2) and the connection structure is such that the outer surface of the hanging portion (32) of the bottom body (3) is only joined to the inner surface of the lower end (2a) of the body (2), the lower heat-sealable resin layer (303) of the bottom blank (30A) can be omitted. The thickness of each laminate (20)(30) is preferably less than 250 μm, and more preferably less than 200 μm. By setting the thickness of each laminate (20)(30) within the above range, problems such as an excessively large step in the portion of the flange portion (23) of the body (2) constituted by the overlap portion (21) and an unstable joint between the lower end portion (2a) and folded portion (22) of the body (2) and the hanging portion (32) of the bottom body (3) can be reliably avoided, as in the case of a paper cup using a laminate having a thickness of about 250 to 400 μm as the blank material.

[0028] The metal foil layers (201) (301) function as a barrier layer to protect the contents from gas, water vapor, light, etc. The metal foil constituting the metal foil layer (201) (301) may be aluminum foil, iron foil, stainless steel foil, copper foil, etc., but aluminum foil is preferably used. In the case of aluminum foil, either pure aluminum foil or aluminum alloy foil may be used, and either soft or hard. For example, annealed soft material (O material) of A8000 series (particularly A8079H or A8021H) classified by JIS H4160 is preferably used because it has excellent formability. In addition, when a hard material (H material) is used as the aluminum foil constituting the metal foil layer (201) (particularly the metal foil layer (201) of the body blank (20A)), the strength of the flange portion (23) is increased, deformation of the flange portion (23) due to unexpected impact is suppressed, and the shape retention of the cup-shaped container (1) as a whole is improved. Both sides of the metal foil layers (201) and (301) are subjected to a base treatment such as a chemical conversion treatment, if necessary. Specifically, for example, the surface of the metal foil that has been degreased is 1) Phosphoric acid, Chromic acid, and at least one compound selected from the group consisting of metal salts of fluorides and nonmetal salts of fluorides. 2) phosphoric acid; At least one resin selected from the group consisting of acrylic resins, chitosan derivative resins, and phenolic resins; and at least one compound selected from the group consisting of chromic acid and chromium (III) salts. 3) phosphoric acid; At least one resin selected from the group consisting of acrylic resins, chitosan derivative resins, and phenolic resins; At least one compound selected from the group consisting of chromic acid and chromium (III) salts; and at least one compound selected from the group consisting of metal salts of fluorides and nonmetal salts of fluorides. A coating is formed by applying an aqueous solution of any one of the above 1) to 3) and then drying the applied solution to perform a chemical conversion treatment. When a soft metal foil (O material) is used as the metal foil layers (201) (301), the surface may be directly subjected to a chemical conversion treatment without being subjected to a degreasing treatment. The coating formed on the surface of the metal foil layer (201) (301) by the above chemical conversion treatment has a chromium deposition amount (per side) of 0.1 mg / m 2 ~50mg / m 2 It is preferable to use a concentration of 2 mg / m 2 ~20mg / m 2 It is preferable to set the above. The thickness of the metal foil layer (201)(301) is preferably 40 to 200 μm, more preferably 80 to 160 μm. By setting the thickness of the metal foil layer (201)(301) within the above range, sufficient barrier properties and moldability can be obtained.

[0029] The heat-sealable resin layers (202), (203), (302), (303) constitute the inner and outer surfaces of the container (1), and serve to protect the metal foil layers (201), (301) and to impart formability to the laminates (20), (30). They also function as heat-sealing layers when joining both end edges (204), (205) of the body blank (20A) and when joining the lower end (2a) and folded portion (22) of the body (2) to the hanging portion (32) of the bottom body (3). The heat-sealable resin layers (202)(203)(302)(303) are usually composed of a general-purpose film having heat-sealability, such as a polypropylene (PP) film or a polyethylene (PE) film, or a composite film made by bonding these together. In particular, a non-oriented polypropylene film (CPP), which has excellent heat resistance and draw formability, is preferable. The heat-sealable resin layers (202)(203)(302)(303) may also be formed of a film or coating layer made of modified polyolefin. Examples of modified polyolefin include polyolefins (polypropylene (PP), polyethylene (PE), copolymers thereof, etc.) modified with carboxylic acids such as maleic acid, fumaric acid, mesaconic acid, citraconic acid, itaconic acid, aconitic acid, crotonic acid, succinic acid, oxalic acid, malonic acid, malic acid, thiomalic acid, tartaric acid, adipic acid, citric acid, pimelic acid, suberic acid, azelaic acid, and sebacic acid, and carboxylic anhydrides such as maleic anhydride, itaconic anhydride, citraconic anhydride, and succinic anhydride. Preferably, maleic acid-modified polyolefins and maleic anhydride-modified polyolefins are used. The thickness of the heat-sealable resin layers (202), (203), (302), (303) is preferably 5 to 80 μm, and more preferably 10 to 60 μm. By setting the thickness of the heat-sealable resin layers (202), (203), (302), (303) within the above range, sufficient adhesive strength can be obtained at the joint between both end edges of the body blank (20A) and at the joint between the lower end (2a) and the folded-back portion (22) of the body (2) and the hanging portion (32) of the bottom body (3), and the step formed by the overlap portion (21) on the upper surface of the flange portion (23) of the body (2) can be made gentle, resulting in good sealing performance when sealed with a lid.

[0030] The metal foil constituting the metal foil layer (201) (301) and the film constituting the heat-fusible resin layer (202) (203) (302) (303) are laminated, for example, by a dry lamination method via an adhesive layer (not shown). For the adhesive layer, for example, a two-component curing polyester-polyurethane adhesive or a polyether-polyurethane adhesive is used. Due to the presence of the adhesive layer, even if the inner heat-sealable resin layer (202) and the outer heat-sealable resin layer (203) of the body blank (20A) are reduced in thickness due to heat fusion, for example, in the overlapping portion (21) of the body (2), the metal foil layers (201) are prevented from coming into contact with each other, so that the sealing performance is maintained. Furthermore, with the adhesive layer, even if contents that permeate the heat-sealable resin layers (202), (203), (302), (303) are filled, it is possible to prevent the metal foil layers (201), (301) from corroding and causing the contents to leak out.

[0031] The laminate (20) constituting the body blank (20A) and the laminate (30) constituting the bottom blank (30A) are usually the same, but may be made of different materials and / or thicknesses.

[0032] In addition to the above configuration, the cup-shaped container (1) of this embodiment has the following characteristic configuration. That is, a tape-shaped sealing material (4) made of a heat-sealing resin is heat-sealed to the inner surface of the body (2) so as to cover the joints (211) between both end edges (204), (205) of the body blank (20A). In addition, the end faces of the inner end edges (204) located on the inside of the body (2) among both end edges of the body blank (20A) are also covered with the tape-shaped sealing material (4). The thermal fusion of the tape-shaped sealing material (4) to the inner surface of the body (2) can be performed by heat sealing using a seal bar, high-frequency sealing or ultrasonic sealing. The tape-shaped sealing material (4) may have an adhesive layer (not shown) laminated on its back surface so that it can be adhered to the inner surface of the body (2).

[0033] The tape-shaped sealing material (4) is usually made by cutting a heat-sealable resin film into a tape shape. The film may have a single layer structure or a multi-layer structure of two or more layers. The tape-shaped sealing material (4) shown in Figures 2 and 5 has a two-layer structure, that is, it is composed of a seal-side heat-sealable resin layer (41) that is heat-sealed to the inner surface of the body (2) and a surface-side heat-sealable resin layer (42) located on the side opposite the inner surface of the body (2). The heat-sealing resin film constituting the tape-shaped sealing material (4) may be a film made of polyolefin such as polypropylene (PP) or polyethylene (PE), or may be a film made of modified polyolefin. Examples of modified polyolefin include polyolefins (polypropylene (PP), polyethylene (PE), copolymers thereof, etc.) modified with carboxylic acids such as maleic acid, fumaric acid, mesaconic acid, citraconic acid, itaconic acid, aconitic acid, crotonic acid, succinic acid, oxalic acid, malonic acid, malic acid, thiomalic acid, tartaric acid, adipic acid, citric acid, pimelic acid, suberic acid, azelaic acid, and sebacic acid, and carboxylic anhydrides such as maleic anhydride, itaconic anhydride, citraconic anhydride, and succinic anhydride. The heat-sealing resin (film) constituting the tape-shaped sealing material 4 is preferably the same as or of the same type as the inner heat-sealing resin layer 202 of the body blank 20A constituting the inner surface of the body 2. This allows the tape-shaped sealing material 4 to be firmly bonded to the inner surface of the body 2.

[0034] When the tape-shaped sealing material (4) is made of two or more heat-sealable resin layers, it is preferable that the surface-side heat-sealable resin layer (42) has a higher melting point than the seal-side heat-sealable resin layer (41). More preferably, the melting point of the surface-side heat-sealable resin layer (42) is higher than that of the seal-side heat-sealable resin layer (41) by 10°C or more. If the two layers (41)(42) have a melting point difference of 10°C or more, when the tape-shaped sealing material (4) is heat-sealed to the inner surface of the body (2) by heat sealing, the adhesion of the molten resin to the seal bar (B) is reliably prevented, and the joining operation can be easily performed (see FIG. 6). Specifically, for example, the melting point of the surface-side heat-sealable resin layer (42) is 135 to 165°C (preferably 150 to 165°C), and the melting point of the seal-side heat-sealable resin layer (41) is 110 to 140°C (preferably 115 to 135°C).

[0035] In addition, the melt mass flow rate (MFR) of the heat-sealing resin constituting the tape-shaped sealing material (4) (in the case of two or more layers, the heat-sealing resin layer (41) on the seal side) is preferably 1 to 20 g / 10 min, more preferably 2 to 10 g / 10 min, and most preferably 4 to 9 g / 10 min. If the MFR of the heat-sealing resin (sealing side heat-sealing resin layer (41)) constituting the tape-shaped sealing material (4) is within the above range, even if a gap occurs between the seam (211) on the inner surface of the body (2) and the tape-shaped sealing material (4), or between the end face of the inner edge portion (204) of the body blank (20A) and the tape-shaped sealing material (4), the gap is filled by the heat-sealing resin that melts when the tape-shaped sealing material (4) is heat-sealed to the inner surface of the body (2), so that the seam (211) and the end face can be covered more reliably. When the tape-shaped sealing material (4) has two or more layers, the MFR of the front-side heat-sealable resin layer (42) is preferably 0.5 to 10 g / 10 min, more preferably 1 to 7 g / 10 min, and most preferably 2 to 4 g / 10 min.

[0036] The length of the tape-shaped sealing material 4 is usually set to be approximately the same as the overall height (H1) (see FIG. 6(a)) of the body blank 20A. Therefore, the tape-shaped sealing material 4 covers the entire length of the joint 211 between both end edges 204, 205 of the body blank 20A. The length of the tape-shaped sealing material (4) may be such that it can cover only a predetermined portion of the entire length of the seam (211). Specifically, the length of the tape-shaped sealing material (4) may be set to a length that can cover the entire length of the seam (211) excluding the flange portion (23), i.e., approximately equal to the total height (H1) of the body blank (20A) minus the height (H3) of the upper fold-back space for forming the flange portion (23), or the length that can cover the entire length of the seam (211) excluding the folded-back portion (22), i.e., approximately equal to the total height (H1) of the body blank (20A) minus the height (H4) of the lower fold-back space for forming the folded-back portion (22). The height (H3) of the upper fold margin and the height (H4) of the lower fold margin can be subtracted from the overall height (H1) of the body blank (20A) to cover only the portion of the overall length of the seam (211) located on the inner surface of the body (2), i.e., the height (H2) approximately equal to the length that can cover the portion of the overall length of the seam (211) excluding the flange portion (23) and the folded portion (22). The width of the tape-shaped sealing material (4) is set, taking into consideration the thickness of the body blank (20A), so as to be heat-sealed to both sides of the seam (211) on the inner surface of the body (2) and to the end face of the inner edge portion (204) of the body blank (20A). Specifically, the width of the tape-shaped sealing material (4) is preferably 2 to 20 mm, and more preferably 5 to 15 mm.

[0037] In the overlap portion (21) of the body (2) of the cup-shaped container (1), the total thickness (T1) of the inner heat-sealable resin layer (202) and the outer heat-sealable resin layer (203) heat-sealed to each other at both end edges (204) and (205) of the body blank (20A) is preferably 8 to 150 μm, more preferably 16 to 80 μm (see FIG. 5). If the total thickness (T1) is less than 8 μm, the sealing property of the overlap portion (21) may be insufficient. On the other hand, if the total thickness (T1) exceeds 150 μm, the barrier property of the overlap portion (21) may be impaired. In the overlap portion (21) of the body (2), the overlap width (W1) between the metal foil layers (201) (201) at both end edges (204) (205) of the body blank (20A) as viewed in the thickness direction is preferably 2 to 10 mm, more preferably 4 to 8 mm. If the overlap width (W1) is less than 2 mm, the barrier properties of the overlap portion (21) may be impaired, and the seal width may become too small, resulting in insufficient sealability. On the other hand, if the overlap width (W1) exceeds 10 mm, the width of the overlap portion (21) will be larger than necessary, leading to increased costs. Furthermore, due to the difference in stress applied to the inner portion of the overlap portion (21) (the inner edge portion (204) of the body blank (20A)) and the outer portion (the outer edge portion (205) of the body blank (20A)), there is a risk of poor appearance, such as wrinkles on the inner portion of the overlap portion (21).

[0038] Next, an example of a method for forming the cup-shaped container 1 using the laminates 20 and 30 will be described. First, the laminate (20) is punched into a substantially sector shape of a predetermined size to form a body blank (20A) (see FIG. 6(a)). The laminate (30) is punched out into a circle of a specified size to form a bottom body blank (30A) (see FIG. 7(a)), and this blank (30A) is drawn using a mold (not shown) to form a bottom body (3) having a generally inverted U-shaped cross section and consisting of a bottom portion (31) and a hanging portion (32) (see FIG. 7(b)). The resulting bottom body (3) is free of wrinkles. The corners between the bottom portion (31) and the hanging portion (32) on the outer surface of the bottom body (3) are rounded. The bottom body (3) is set on the top surface of a generally truncated cone mold (not shown) so that the upper surface of the bottom part (31) overlaps, and the body blank (20A) is wrapped around the outer periphery of the mold so that both end edges overlap, and then the inner heat-sealable resin layer (202) and the outer heat-sealable resin layer (203) which form the overlapping surfaces of the overlapping part (21) are heat-sealed to form the tapered cylindrical body (2) (see FIG. 6(b)). The means for heat-sealing the overlapping part (21) may be heat sealing using a seal bar, high-frequency sealing, ultrasonic sealing, or the like. Here, when the inner heat-sealable resin layer (202) and the outer heat-sealable resin layer (203) are made of a non-oriented polypropylene film (CPP), the heat sealing is preferably performed under the conditions of a sealing temperature of 160 to 220°C, a load of 80 to 200 kgf, and a sealing time of 1 to 5 seconds. When the inner heat-sealable resin layer (202) and the outer heat-sealable resin layer (203) are made of a polyethylene film (PE), the heat sealing is preferably performed under the conditions of a sealing temperature of 140 to 220°C, a load of 80 to 200 kgf, and a sealing time of 1 to 5 seconds. In other words, in the case of heat sealing, it is preferable to heat both ends of the overlapped body blank (20A) at a temperature 20 to 40°C higher than the melting point of the resin constituting the heat-sealable resin layers (202) and (203) from both sides. Moreover, the high frequency sealing is preferably performed under the conditions of, for example, output: 0.5 to 1.5 kW, sealing time: 3 to 5 seconds, distance from the coil: 0.5 to 15 mm, and load: 100 to 200 kgf. Also, tape-shaped sealing material (4) is placed on the inner surface of the body (2) so as to span the seam (211) between both end edges of the body blank (20A), and heat-sealing is performed with a seal bar (B) (see Fig. 6(c)). As a result, the seam (211) on the inner surface of the body (2) and the end face of the inner edge portion (204) of the body blank (20A) are covered with the tape-shaped sealing material (4) without creating a gap between them (see Figs. 5 and 6(d)). The preferable conditions for heat-sealing the tape-shaped sealing material (4) to the inner surface of the body (2) are the same as those for heat-sealing the overlap portion (21) of the body (2). Next, as shown in Fig. 8, the lower opening edge of the body (2) is folded inward, and the folded portion (22) is pressed against the hanging portion (32) of the bottom body (3) by a disk-shaped rotating die (not shown), and then the inner heat-sealable resin layer (202), the upper heat-sealable resin layer (302), and the lower heat-sealable resin layer (303), which constitute the overlapping surfaces of the lower end (2a) and folded portion (22) of the body (2) and the hanging portion (32) of the bottom body (3), are heat-sealed to join the body (2) and the bottom body (3) together. The heat-sealing of these heat-sealable resin layers (202), (302), and (303) is usually performed by heat sealing using a seal bar, but may also be performed by high-frequency sealing, ultrasonic sealing, or the like. The preferred conditions for heat sealing and high frequency sealing are the same as those for heat fusing the overlapping portion (21) of the body (2). In addition, the upper opening edge of the body (2) is curled outward using a specified curl forming die (not shown) and pressed vertically to form a flat shape, thereby forming a flange portion (23) (see Figure 8). In this way, the cup-shaped container (1) shown in Figures 1 to 3 is obtained.

[0039] The cup-shaped container (1) of this embodiment provides the following advantages. a) The body blank (20A) and the bottom blank (30A) are each formed from a laminate (20) (30) consisting of a metal foil layer (201) (301) and heat-sealable resin layers (202) (203) (302) (303) laminated on both sides thereof, and therefore can be produced inexpensively using paper cup production equipment. b) The laminates (20) (30) from which the blanks (20A) (30A) are made have metal foil layers (201) (301), so that the contents can be stored for a long time. c) Since the thickness of the body blank (20A) is smaller than that of a paper cup, the step on the upper surface of the flange portion (23) of the body (2) formed by the overlap portion (21) can be made smaller, and therefore poor sealing is less likely to occur when sealing the lid to the upper surface of the flange portion (23) of the container (1). Also, when performing aseptic (sterile) filling, sterilizing liquid is less likely to remain in the step on the upper surface of the flange portion (23). d) Since the bottom body (3) is formed by drawing the bottom body blank (30A), wrinkles do not occur in the bottom body (3). Therefore, there is no risk of poor bonding between the hanging portion (32) of the bottom body (3) and the lower end portion (2a) and the folded portion (22) of the body (2) or of reduced barrier properties, as occurs with conventional paper cups. e) Since the thickness of the body blank (20A) and the bottom blank (30A) is smaller than that of a paper cup, the lower end (2a) and the folded portion (22) of the body (2) can be stably joined to the hanging portion (32) of the bottom body (3). f) Compared to a paper cup, the radius of curvature (R) of the corner portion between the bottom portion (31) and the hanging portion (32) on the outer surface of the base body (3) can be made smaller, so that when performing aseptic filling, sterilizing liquid is less likely to remain at the boundary between the upper surface of the bottom body (3) and the inner surface of the body (2) of the cup-shaped container (1). g) Since the laminates 20, 30 from which the blanks 20A, 30A are made do not have a paper layer, retort sterilization can be carried out without any problems. h) The tape-like sealing material (4) made of a heat-sealing resin is heat-sealed to the inner surface of the body (2) so as to cover the joint (211) between both end edges (204), (205) of the body blank (20A), so that the sealing performance of the joint (211) is dramatically improved and leakage of the contents can be reliably prevented. In addition, the end face of the inner end edge (204) of the body blank (20A) is also covered with the tape-like sealing material (4), so that the end face can be effectively prevented from being exposed to the contents and causing delamination or corrosion. Furthermore, since both end edges (204), (205) of the body blank (20A) are overlapped and joined together, even if the tape-shaped sealing material (4) is heat-sealed to the inner surface of the body (2), the number of layers constituting the overlap portion (21) of the body (2) is reduced. This makes it possible to easily perform processing such as forming a flange portion (23) at the upper opening edge of the body (2) and forming a folded portion (22) at the lower opening edge of the body (2) without hindrance when manufacturing the container (1).

[0040] <Second embodiment> Figures 9 to 12 show a cup-shaped container (1X) according to a second embodiment of the present invention. This embodiment is substantially the same as the cup-shaped container (1) of the first embodiment shown in Figures 1 to 8, except for the following points. That is, as shown in Figures 9 to 11, in the cup-shaped container 1X of this embodiment, the body 2 is formed into a cylindrical shape by overlapping and joining both end edges 204, 205 of the body blank 20A in a palm-to-palm shape (see Figure 12(a)). More specifically, the overlapping both end edges 204, 205 of the body blank 20A in a palm-to-palm shape are joined by heat-sealing their inner heat-sealable resin layers 202 to each other. Also, the joint portion (21X) of the body (2) is heat-sealed to an outer heat-sealable resin layer (203) of the body blank (20A) which is folded to one side so as to overlap with the outer surface of the body (2) and forms the outer surface of the body (2) (see Figs. 11 and 12(b)). Note that, in the case where the joint portion (21X) is not heat-sealed to the outer surface of the body (2), the outer heat-sealable resin layer (203) of the body blank (20A) can be omitted. The width (overlap) of the joint portion (21X) of the body (2) is preferably 5 to 20 mm, and more preferably 10 to 18 mm. If the width is less than 5 mm, sealing the joint portion (21X) may be difficult. On the other hand, if the width exceeds 20 mm, the width of the joint portion (21X) becomes larger than necessary, leading to increased costs. Furthermore, when the joint portion (21X) is folded to one side so as to overlap with the outer surface of the body (2) and joined to the outer surface, wrinkles or other defects in appearance may occur in the joint portion (21X). A tape-shaped sealing material (4X) made of a heat-sealing resin is heat-sealed to the inner surface of the body (2) so as to cover the seam (211X) between both end edges (204), (205) of the body blank (20A). The heat fusion of the tape-shaped sealing material (4X) is usually performed by placing the tape-shaped sealing material (4X) on the inner surface of the body (2) so as to span the seam (211X) between both end edges (204), (205) of the body blank (20A) and heat sealing using a seal bar (B) (see FIG. 12(c)). As a result, the seam (211) on the inner surface of the body (2) is covered by the tape-shaped sealing material (4X) without creating a gap between the two (see FIGS. 11 and 12(d)). The tape-shaped sealing material (4X) may also be laminated with an adhesive layer (not shown) on its back surface so that it is adhered to the inner surface of the body (2).

[0041] Therefore, in the case of the cup-shaped container (1X) of the second embodiment, the tape-shaped sealing material (4X) dramatically improves the sealing property of the joint (211X) between both end edges (204), (205) of the body blank (20A) on the inner surface of the body (2), thereby reliably preventing leakage of the contents. Furthermore, according to the above-mentioned cup-shaped container (1X), regardless of the presence or absence of the tape-like sealing material (4X), the end faces of the two end edge portions (204), (205) of the body blank (20A) do not come into contact with the contents contained in the container (1X), thereby reliably suppressing the occurrence of delamination, corrosion, etc. at the end faces. Furthermore, according to the above cup-shaped container (1X), the joint portion (21X) of the body (2) is bent to one side and heat-sealed to the outer surface of the body (2), improving the sealing and barrier properties of the same part. Moreover, according to the cup-shaped container (1X), the joint portion (21X) does not protrude outward, improving the appearance and making it easier to hold.

[0042] <Third embodiment> Fig. 13 shows a cup-shaped container (1Y) according to a third embodiment of the present invention. This embodiment is substantially the same as the cup-shaped container (1X) according to the second embodiment shown in Figs. 9 to 12, except for the following points. That is, as shown in FIG. 13, in the cup-shaped container (1Y) of this embodiment, in addition to the tape-shaped sealing material (4X) heat-sealed to the inner surface of the body (2), a tape-shaped sealing material (4Y) is also heat-sealed to the outer surface of the body (2) so as to cover both end faces (204a) and (205b) of the body blank (20A). The tape-shaped sealing material 4Y is usually heat-sealed by arranging the tape-shaped sealing material 4Y so as to straddle the outer surface of the folded joint portion 21X and the outer surface of the body 2 adjacent to the outer surface of the joint portion 21X, sandwiching both end surfaces 204a, 205a of the body blank 20A, and then heat sealing, high-frequency sealing, etc. As a result, both end surfaces 204a, 205a of the body blank 20A located on the outside of the body 2 are covered with the tape-shaped sealing material 4Y. Therefore, according to the cup-shaped container (1Y) of this embodiment, deterioration due to delamination and corrosion of both end faces (204a) (205a) of the body blank (20A) is effectively suppressed for a long period of time, and the sealing property of the joint portion (21X) of the body (2) is further improved. The material, configuration, dimensions, etc. of the tape-shaped sealing material (4Y) may be the same as those of the tape-shaped sealing materials (4) (4X) of the first and second embodiments. The tape-shaped sealing material (4Y) may have an adhesive layer (not shown) laminated on its back surface so that it is adhered to the outer surface of the body (2). In this embodiment, the thermal fusion between the folded joint portion (21X) and the outer surface of the body (2) may be omitted since the tape-shaped sealing material (4Y) provides substantially the same joining function. In addition, in this embodiment, if sufficient sealing performance is obtained from the tape-shaped sealing material (4Y) joined to the outer surface of the body, the tape-shaped sealing material (4X) joined to the inner surface of the body (2) may be omitted. EXAMPLES

[0043] Next, specific examples of the present invention will be described, but the present invention is not limited to these examples.

[0044] <Example 1> A two-component curing urethane adhesive was applied at approximately 3 g / m2 to both sides of a 100 μm thick aluminum foil (A8021H-O) that had been chemically treated. 2 The adhesive was applied and dry laminated to a 30 μm-thick non-oriented polypropylene film (CPP), and then a predetermined aging treatment was performed to harden the adhesive, thereby obtaining a laminate. Next, the obtained laminate was punched into a predetermined shape by a die-cutting method to form a body blank and a bottom blank (see Figs. 6 and 7). A 40 μm thick film made of random polypropylene (rPP) (melting point: 125° C., MFR: 7 g / 10 min) was cut into a tape to prepare a tape-shaped sealing material with a length of 109 mm and a width of 10 mm. Then, using the above-mentioned body blank, bottom blank and tape-like sealing material, a cup-shaped container shown in Figures 1 to 3 was produced using the same steps as in the first embodiment described above, and this was designated Example 1. The heat fusion of both end edges of the body blank was carried out by heat sealing the overlapping portion and its surrounding area in two separate steps using a 5 mm wide seal bar under the following sealing conditions: sealing temperature: 180°C, load: 150 kgf, sealing time: 2 seconds. The tape-shaped sealing material was heat-sealed to the inner surface of the body by heat-sealing a 10 mm width of the tape-shaped sealing material three times using a 5 mm wide sealing bar. The sealing conditions were sealing temperature: 180°C, load: 150 kgf, and sealing time: 2 seconds. The resulting cup-shaped container is made of aluminum foil with a thickness of 100 μm, and therefore has excellent barrier properties with almost no permeation of oxygen or water vapor. The dimensions of the cup-shaped container were as follows: -Inner diameter of the opening at the top of the cup-shaped container: 65mm -Inner diameter of the bottom of the cup-shaped container: 50mm Flange width: 4mm Height of cup: 95mm Height of cup-shaped container legs (folded part): 6mm

[0045] <Comparative Example 1> A cup-shaped container was produced in the same manner as in Example 1, except that no tape-like sealing material was used. This was used as Comparative Example 1.

[0046] <Production of packaging samples and verification of sealing and corrosion resistance> A 12 μm-thick biaxially oriented polyethylene terephthalate film, a 20 μm-thick aluminum foil (A8021H-O), and a 30 μm-thick unoriented polypropylene resin film (CPP) that constitutes the heat seal layer were bonded together in this order by the dry lamination method using a two-component curing urethane adhesive to form a laminate, and the lid material was produced by punching this laminate into the specified shape. Next, the cup-shaped containers of Example 1 and Comparative Example 1 were filled with a test liquid prepared by mixing 3% by mass salt solution and soy sauce (manufactured by Kikkoman Corporation) in a 1:1 ratio up to a level 10 mm below the flange. The lid material was then heat-sealed to the flange of each cup-shaped container containing the test liquid to obtain a package sample.

[0047] Each of the obtained package samples was stored in an environment at a temperature of 40° C. for one week, after which the lid was opened to drain the test liquid, and the inside of the body of each cup-shaped container was visually observed. No seal leakage was observed from the joints between both end edges of the body blank in the cup-shaped container of Example 1. In addition, when the tape-like sealing material was peeled off and the end face of the aluminum foil at the inner edge of the body blank was observed, no discoloration due to soy sauce was observed, and no corrosion or delamination had occurred. On the other hand, in the case of the cup-shaped container of Comparative Example 1, corrosion was found on the end surface of the aluminum foil at the inner edge of the body blank, and delamination occurred between the aluminum foil and the CPP, with slight sealing leakage. [Industrial Applicability]

[0048] The present invention can be suitably used as a cup-shaped container for holding, for example, liquid food or beverage. [Explanation of symbols]

[0049] (1)(1X)(1Y): Cup-shaped container (2): Torso (2a): Lower end of the fuselage (20A): Body blank (20): Laminate (201): Metal foil layer (202): Inner heat-sealable resin layer (203):Outer heat-fusible resin layer (204): Inner edge (one edge) (205): Outer edge (other edge) (204a)(205a): Both end faces (of the fuselage blank) (21): Overlap section (21X): Gassho part (211)(211X): The joint between the two ends of the fuselage blank on the inside of the fuselage (23): Flange (3): Bottom body (31):Bottom (32): Drooping part (30A): Bottom blank (30): Laminate (301):Metal foil layer (302): Upper heat-sealable resin layer (303): Lower heat-fusible resin layer (4)(4X)(4Y): Tape-type sealing material (41): Surface side heat-fusible resin layer (42): Heat-sealing resin layer on the sealing side

Claims

1. A cup-shaped container comprising a body formed into a cylindrical shape by overlapping and joining both end edges of a body blank, and a bottom body having a generally inverted U-shaped cross section formed by forming a bottom body blank so as to form a bottom and a hanging part extending downward from the outer peripheral edge of the bottom body, the body and the bottom body being integrated by joining the outer surface of the hanging part of the bottom body to the inner surface of the lower end of the body, the body blank is formed from a laminate consisting of a metal foil layer and a heat-sealable resin layer laminated on at least one of both sides of the metal foil layer that will become the inside of the body, the blank does not have a paper layer, and both end edges of the body blank are joined by heat-sealing the heat-sealable resin layers that constitute the mutually overlapping surfaces, The bottom body blank is formed from a laminate consisting of a metal foil layer and a heat-sealable resin layer laminated on at least one of both sides of the metal foil layer that will be the upper side of the bottom body, and the inner surface of the lower end of the body and the outer surface of the hanging part of the bottom body are joined by heat-sealing the heat-sealable resin layers that make up these surfaces, a tape-like sealing material is bonded to an inner surface of the body so as to cover a seam between both end edges of the body blank; The tape-shaped sealing material is made of a heat-sealable resin at least on the joining surface side with the inner surface of the body, and is heat-sealed to the inner surface of the body; A cup-shaped container, comprising a body blank in which a metal foil constituting a metal foil layer and a film constituting a heat-fusible resin layer are laminated via an adhesive layer.

2. 2. The cup-shaped container according to claim 1, wherein the adhesive constituting the adhesive layer is a two-component curing type polyester-polyurethane adhesive or polyether-polyurethane adhesive.

3. The body blank is formed from a laminate including a metal foil layer and a heat-fusible resin layer laminated on both sides of the metal foil layer, Both end edge portions of the fuselage blank are overlapped and joined by heat-sealing the heat-sealable resin layers constituting the overlapping surfaces of the fuselage blank, 3. The cup-shaped container according to claim 1, wherein the end faces of the inner edge portions located on the inside of the body of the container, of both end edge portions of the body blank, are covered with a tape-like sealing material.

4. 4. A cup-shaped container as claimed in claim 3, wherein the width of the portion of the tape-shaped sealing material which is joined to the inner surface of the inner edge portion located on the inside of the body, among both end edges of the body blank, is made larger than the overlap width of both end edges of the body blank.

5. An outwardly bent flange is provided at the upper opening edge of the body, 5. The cup-shaped container according to claim 1, wherein the joints between both end edges of the body blank, except for the portion for forming the flange portion, are covered with a tape-like sealing material.

6. The body further has a folded-back portion that is folded inward from the lower end opening edge portion thereof so as to enclose the hanging portion of the bottom body and extend upward, The folded portion of the body and the hanging portion of the bottom body are joined by heat-sealing the heat-sealable resin layers constituting the overlapping surfaces of the folded portion and the hanging portion of the bottom body, 6. The cup-shaped container according to claim 1, wherein the seams between both end edges of the body blank, excluding the portions for forming the folded-back portions, are covered with a tape-like sealing material.

7. 5. The cup-shaped container according to claim 1, wherein only a portion of the seam between both end edges of the body blank that is positioned on the inner surface of the body is covered with a tape-like sealing material.

8. A cup-shaped container according to any one of claims 1 to 7, wherein the heat-sealing resin constituting at least the joining surface side of the tape-shaped sealing material with the inner surface of the body is the same or of the same type as the heat-sealing resin layer of the body blank constituting the inner surface of the body.

9. 9. The cup-shaped container according to claim 1, wherein the melt mass flow rate (MFR) of the heat-sealable resin constituting at least the joining surface side with the inner surface of the body of the tape-shaped sealing material is 1 to 20 g / 10 min.

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