Molded container, and package

Abstract

To provide a molded container whose side wall part has increased strength while securing moldability.SOLUTION: A molded container 1 is obtained by molding a laminate 10 comprising a metal foil layer 12 and synthetic resin layers 11, 13 covering both surfaces of the metal foil layer 12. A bottom wall part 2 of the molded container 1 is made to be smaller than an opening 6, as viewed from a flat surface. A shape of the bottom wall part 2 is circle-shaped or oval-shaped as viewed from the flat surface; and a circumferential shape of the bottom wall part 2 is substantially polygonal smaller than the opening 6 as viewed from the flat surface. Each side 21 of a circumference of the bottom wall part 2 is located on each side of a virtual polygon having a tip on a virtual oval V whose center is located on the same vertical line as a center of the opening 6, while being a similar figure to the opening 6; and adjacent sides 21 are connected to each other so as to form an obtuse angle.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] This invention relates to a molded container and a package.

[0002] In this specification and the claims, the term "aluminum" shall include aluminum alloys in addition to pure aluminum.

[0003] Also, in this specification and the claims, as shown in the drawings, the lower side of FIG. 1 is referred to as the front, the opposite side as the rear, the left and right sides of FIGS. 1 and 2 as the left and right, and the upper and lower sides of FIG. 2 as the upper and lower.

[0004] Also, in this specification and the claims, the term "oval" means a shape in which both ends of two curves that bulge in a curved manner in opposite directions and have the same radius of curvature are smoothly connected by two curves that bulge in a curved manner in opposite directions and have a radius of curvature different from the two curves, and shapes similar to the shape, and an ellipse.

[0005] Furthermore, in this specification and the claims, the sides constituting a "substantially polygon" are not limited to straight lines but also include curves.

Background Art

[0006] In the food field with contents such as beverages, puddings, jellies, yogurts, semi-solid products such as butter and jams, and foods containing fats and liquids such as curries, canned tuna, and soups, the medical and pharmaceutical field with contents such as oral medications and transdermal absorption medications such as compresses, and medical products requiring sterile packs, the industrial field with contents such as greases, adhesives, and oils, and the electronic component field with contents such as electronic components, etc., for packaging the contents, a molded container having a bottom wall portion, a side wall portion integrally provided in a rising manner at the periphery of the bottom wall portion, and an opening surrounded by the upper end of the side wall portion is used.

[0007] As an example of the above-described formed container, the one described in Patent Document 1 is known. The formed container described in Patent Document 1 is obtained by subjecting a laminate in which a first resin layer, a metal foil layer, and a second resin layer are laminated in this order to press forming processes such as drawing forming and protrusion forming, and includes a bottom wall portion, a side wall portion integrally provided in a rising manner at the periphery of the bottom wall portion, and an outward flange portion integrally provided at the upper end of the side wall portion. It has a storage portion surrounded by the bottom wall portion and the side wall portion, and is formed in a cup shape with the upper end of the storage portion being an opening. The bottom wall portion is smaller than the opening when viewed from a plane, and the shape of the periphery of the bottom wall portion is similar to the opening and the center is on the same vertical line as the center of the opening. Patent Document 1 gives, as specific examples of the shapes of the opening and the periphery of the bottom wall portion, a square having rounded corners and an oval shape.

[0008] In the case of the formed container described in Patent Document 1, when the height of the side wall portion is increased to increase the depth of the storage portion, it is made by deep drawing forming. Since the shape of the opening is circular or oval, the material is evenly distributed over the entire circumference of the opening during deep drawing forming, resulting in excellent formability and making it less likely for wrinkles to occur in the flange portion. As a result, the sealing performance when heat-sealing the peripheral edge of the lid to the upper surface of the flange portion is improved. Moreover, it becomes easier to manufacture the mold for forming and the container receiving portion of the content filling device.

Prior Art Documents

Patent Documents

[0009]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0010] However, in the case of the formed container described in Patent Document 1, depending on the type and usage mode of the content, there is a risk that the strength of the bottom wall portion and the side wall portion may be insufficient.

[0011] This invention has been made in view of the above circumstances, and an object thereof is to provide a formed container having increased strength of the side wall portion while ensuring moldability.

Means for Solving the Problems

[0012] In order to achieve the above object, this invention comprises the following aspects.

[0013] 1) A formed container formed by molding a laminate composed of a metal foil layer and synthetic resin layers covering both sides of the metal foil layer into a cup shape, and comprising a bottom wall portion, a side wall portion integrally provided in a rising shape at the periphery of the bottom wall portion, and an outward flange portion integrally provided at the upper end of the side wall portion, and having a storage portion surrounded by the bottom wall portion and the side wall portion and an upper end of the storage portion being an opening, wherein the bottom wall portion is smaller than the opening when viewed from a plane, the shape of the opening is circular or oval when viewed from a plane, and the shape of the periphery of the bottom wall portion is a substantially polygon smaller than the opening when viewed from a plane and adjacent sides are connected at a certain angle, the formed container.

[0014] 2) The formed container according to 1) above, wherein the shape of the peripheral portion of the bottom wall portion is a substantially polygon having 4 or more sides when viewed from a plane.

[0015] 3) An annular step protruding inward is provided over the entire circumference at an intermediate portion in the height direction of the side wall portion, and both inner and outer peripheral edges of the annular step are similar in shape to the opening when viewed from a plane and the center is on the same vertical line as the center of the opening, the formed container according to 1) above.

[0016] 4) The formed container according to 1) above, wherein the distance between the periphery of the opening and the periphery of the bottom wall portion is 5 mm or less over the entire circumference when viewed from a plane.

[0017] 5) The shape of the periphery of the bottom wall portion is a substantially polygon having five or more sides consisting of straight lines, and all sides of the substantially polygon are similar to the opening and vertices are located on each side of a virtual polygon having vertices on a virtual circle or a virtual oval whose center is on the same vertical line as the center of the opening. The formed container according to 1) above.

[0018] 6) The shape of the periphery of the bottom wall portion is composed of three or more first sides consisting of straight lines arranged at intervals and the same number of second sides consisting of curves arranged so as to connect adjacent first sides. The first side is similar to the opening and vertices are located on each side of a virtual polygon having vertices on a virtual circle or a virtual oval whose center is on the same vertical line as the center of the opening, and the second side is located on the virtual circle or the virtual oval. The formed container according to 1) above.

[0019] 7) A packaging body in which a content is placed in the accommodating portion of the formed container according to any one of 1) to 6) above, and the opening of the formed container is closed by a lid whose peripheral portion is heat-sealed to the flange portion.

Advantages of the Invention

[0020] According to the formed containers of 1) to 6) above, since the shape of the opening is circular or oval when viewed from the plane, in order to increase the depth of the accommodating portion, even if it is manufactured by subjecting a laminate composed of a metal foil layer and a synthetic resin layer covering both sides of the metal foil layer to press forming such as deep drawing, the material is evenly distributed over the entire circumference of the opening, resulting in excellent formability and suppressing the occurrence of wrinkles in the flange portion. Therefore, the sealing performance when heat-sealing the peripheral portion of the lid to the upper surface of the flange portion is improved. Moreover, it becomes easy to manufacture a mold for forming and a container receiving portion of the content filling device.

[0021] In addition, since the shape of the periphery of the bottom wall portion is a substantially polygon smaller than the opening as viewed from the plane, and adjacent sides are connected such that they form a certain angle, the strength of the bottom wall portion is greater than that of the formed container described in Patent Document 1. Further, when manufactured by deep drawing, the horizontal cross-sectional shape of the portion of the side wall portion from the bottom wall portion to a certain height is a substantially polygon similar to the shape viewed from the plane of the bottom wall portion, and adjacent sides are connected such that they form a certain angle, so that the strength of the side wall portion also increases. Therefore, deformation when receiving an external force is suppressed.

[0022] According to the formed container of 2) above, the strength of the bottom wall portion and the side wall portion is effectively increased.

[0023] According to the formed container of 3) above, the strength of the side wall portion further increases. Moreover, the stackability when stacking a plurality of containers is improved.

[0024] According to the formed container of 4) above, even if manufactured by press forming such as deep drawing, wrinkles and pinholes are less likely to occur in the bottom wall portion and the side wall portion.

[0025] According to the formed containers of 5) and 6) above, press forming such as deep drawing can be easily performed.

Brief Description of the Drawings

[0026]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Embodiments for Carrying out the Invention

[0027] Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the technical scope of the present invention is not limited by the embodiments shown in the drawings.

[0028] Figs. 1 to 4 show the formed container according to the present invention, Fig. 5 shows the laminate used for manufacturing the formed containers of Figs. 1 to 4, and Fig. 6 shows the package using the formed containers of Figs. 1 to 4.

[0029] In Figs. 1 to 4, the formed container (1) according to the present invention is formed into a cup shape by deep drawing a laminate (10) (see Fig. 5), and includes a bottom wall portion (2), a side wall portion (3) integrally provided in a rising shape at the periphery of the bottom wall portion (2), and an outward flange portion (4) integrally provided at the upper end of the side wall portion (3). It has a storage portion (5) surrounded by the bottom wall portion (2) and the side wall portion (3), and the upper end of the storage portion (5) is an opening (6) surrounded by the upper end of the side wall portion (3).

[0030] As shown in Fig. 1, the bottom wall portion (2) of the forming container (1) is smaller than the opening (6) when viewed from the plane. The shape of the opening (6) of the forming container (1) is oval when viewed from the plane, and the shape of the periphery of the bottom wall portion (2) is a substantially polygon having more than 4 sides and smaller than the opening (6) when viewed from the plane, and adjacent sides (21) are connected so as to form a certain angle. In the embodiment shown in Figs. 1 to 4, the shape of the periphery of the bottom wall portion (2) of the forming container (1) is a substantially decagon in which all sides (21) are straight lines when viewed from the plane, and each side (21) is similar to the opening (6) and has a vertex on each side of a virtual decagon having a center (O) on the same vertical line as the center of the opening (6). The adjacent sides (21) are connected so as to form an obtuse angle. That is, the shape of the bottom wall portion (2) is a flat substantially decagon that is long in the left-right direction when viewed from the plane, and has a major axis (L) extending in the left-right direction passing through the center (O) of the virtual oval (V), and a minor axis (S) that is orthogonal to the major axis (L) and extends in the front-rear direction passing through the center (O) of the virtual oval (V). Two vertices are located on the major axis (L), and the center of the length of a pair of opposite sides (21) is located on the minor axis (S). Here, the above-described virtual oval (V) is composed of an arc bulging rearward with a point (P1) at a certain distance X forward from the center (O) on the minor axis (S) as the center of curvature, an arc bulging forward with a point (P2) at a certain distance X rearward from the center (O) on the minor axis (S) as the center of curvature, an arc bulging leftward with a point (P3) at a certain distance Y leftward from the center (O) on the major axis (L) as the center of curvature, and an arc bulging rightward with a point (P4) at a certain distance Y rightward from the center (O) on the major axis (L) as the center of curvature. In addition, a roundness with a small radius of curvature is formed at the connecting portion between two adjacent sides (21).

[0031] Further, when viewed from a plane, it is preferable that the distance between the periphery of the opening (6) and the periphery of the bottom wall portion (2) is 5 mm or less over the entire circumference. In this case, even if the laminate (10) is manufactured by press forming such as deep drawing, wrinkles and pinholes are less likely to occur in the bottom wall portion (2) and the side wall portion (3). Further, the bottom wall portion (2) has an annular step (22) at a position having a certain distance inward from its periphery, and the inner portion of the annular step (22) is made slightly higher than the outer portion. The shape of the annular step (22) is similar to the periphery of the bottom wall portion (2) when viewed from a plane and the center is the same as the center of the periphery of the bottom wall portion (2).

[0032] An annular step (31) protruding inward is provided over the entire circumference at an intermediate portion in the height direction of the side wall portion (3) of the forming container (1). The shapes of the inner and outer peripheral edges of the annular step (31) are similar to the opening (6) when viewed from a plane and the center is on the same vertical line as the center of the opening (6). Further, the horizontal cross-sectional shape of the portion of the side wall portion (3) from the bottom wall portion (2) to a certain height is a substantially polygon similar to the shape of the bottom wall portion (2) when viewed from a plane, and adjacent sides are connected so as to form a certain angle. On the side wall portion (3), a ridge line portion (32) extending upward from the apex portion of the substantially polygon which is the shape of the periphery of the bottom wall portion (2) and having a certain height is formed.

[0033] As shown in FIG. 5, the laminate (10) is obtained by laminating a first resin layer (11), a metal foil layer (12), and a second resin layer (13) in this order from one side. An adhesive layer may be interposed between the first resin layer (11) and the metal foil layer (12) and between the second resin layer (13) and the metal foil layer (12).

[0034] The first resin layer (11) constitutes the outer surface side of the bottom wall portion (2) and the side wall portion (3), and the lower surface side of the flange portion (4). It is preferably formed of a synthetic resin film made of an unstretched film or a biaxially stretched film such as polyolefin, polyester, or polyamide. As the polyolefin, high-density polyethylene (HDPE), low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), homopolypropylene (hPP), propylene-ethylene random copolymer (rPP), propylene-ethylene block copolymer (bPP), etc. are exemplified. As the polyester, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polybutylene terephthalate (PBT) are exemplified. As the polyamide, PA6 is exemplified. The thickness of the first resin layer (11) made of a synthetic resin film is preferably 10 to 100 μm. As the synthetic resin film forming the first resin layer (11), either a multilayer film or a single-layer film may be used, but an unstretched film is preferably used, and particularly an unstretched polypropylene film is preferably used.

[0035] Also, the first resin layer (11) may be made of an overcoat agent. The first resin layer (11) made of an overcoat agent is preferably formed to have a thickness of 2 to 10 μm by, for example, epoxy resin coating, olefin resin coating, or acrylic resin coating.

[0036] The metal foil layer (12) is a barrier layer for protecting the contents of the package using the formed container (1) from gas, water vapor, light, etc. It is preferably formed of a metal foil with a thickness of 50 to 200 μm. The metal foil is formed of a metal such as aluminum, copper, iron (stainless steel), titanium, etc. However, considering the barrier function, processability, cost, etc., it is preferable to use an aluminum foil. As the aluminum foil, it is particularly preferable to use a foil made of aluminum of the 1000 series or 8000 series defined in JIS H4160:1994. Specifically, A8021, A8079, A1N30, etc. are preferably used.

[0037] The second resin layer (13) forms the inner surface side of the bottom wall portion (2) and the side wall portion (3), and the upper surface side of the flange portion (4). It is preferably formed of a thermoplastic synthetic resin film made of an unstretched film or a biaxially stretched film such as polyolefin, polyester, or polyamide. Examples of polyolefin include high-density polyethylene (HDPE), low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), homopolypropylene (hPP), propylene-ethylene random copolymer (rPP), and propylene-ethylene block copolymer (bPP). Examples of polyester include polyethylene terephthalate (PET), polyethylene naphthalate (PEN), and polybutylene terephthalate (PBT). An example of polyamide is PA6. The thickness of the second resin layer (13) made of a thermoplastic synthetic resin film is preferably 50 to 400 μm. The synthetic resin film forming the second resin layer (13) may be either a multilayer film or a single-layer film, but it is preferably an unstretched film, and particularly preferably an unstretched polypropylene film.

[0038] FIG. 6 shows a package using the formed container (1) shown in FIGS. 1 to 4.

[0039] In FIG. 6, the package (100) is composed of a formed container (1) and a lid (101). That is, the content (not shown) is placed in the accommodating portion (5) of the formed container (1), and the upper end opening (6) of the accommodating portion (5) is closed by a lid (101) whose lower surface of the peripheral portion is heat-sealed to the upper surface of the outward flange portion (4), thereby being used as the package (100).

[0040] FIGS. 7 and 8 show other embodiments of the formed container according to the present invention.

[0041] The formed container (40) shown in Fig. 7 is formed into a cup shape by deep drawing the laminate (10), and includes a bottom wall portion (41), a side wall portion (3) integrally provided in a rising manner at the periphery of the bottom wall portion (41), and an outward flange portion (4) integrally provided at the upper end of the side wall portion (3). It has a receiving portion (5) surrounded by the bottom wall portion (41) and the side wall portion (3), and the upper end of the receiving portion (5) is an opening (6) surrounded by the upper end of the side wall portion (3).

[0042] The main difference between the formed container (40) and the formed container (1) shown in Figs. 1 to 4 is the shape of the periphery of the bottom wall portion (41) which is smaller than the opening (6) when viewed from the plane. The shape of the periphery of the bottom wall portion (41) is a flat substantially 12-sided polygon that is long in the left-right direction when viewed from the plane, and has a major axis (L) extending in the left-right direction passing through the center (O) of a virtual oval (V) similar to that in Fig. 1, and a minor axis (S) orthogonal to the major axis (L) and extending in the front-rear direction passing through the center (O) of the virtual oval (V). It consists of three or more, here six, first sides (411) formed of straight lines arranged at intervals, and the same number of second sides (412) formed of curves arranged so as to connect adjacent first sides (411). And the centers of the lengths of a pair of second sides (412) facing each other on the major axis (L) are located, and the centers of the lengths of a pair of first sides (411) facing each other on the minor axis (S) are located.

[0043] Each first side (411) formed of a straight line that constitutes the shape of the periphery of the bottom wall portion (41) of the formed container (40) is located on each side at intervals of a virtual 12-sided polygon having vertices on a virtual oval (V) similar to that in Fig. 1, and both ends of the first side (411) are located on the virtual oval (V), and the second side (412) formed of a curve is located on the virtual oval (V). And adjacent sides (411)(412) are connected so as to form an obtuse angle. That is, the tangent of the end portion on the first side (411) side of the second side (412) formed of a curve and the first side (411) formed of a straight line form an obtuse angle.

[0044] The formed container (50) shown in Fig. 8 is formed into a cup shape by deep drawing the laminate (10), and comprises a bottom wall portion (51), a side wall portion (3) integrally provided upright at the periphery of the bottom wall portion (51), and an outward flange portion (4) integrally provided at the upper end of the side wall portion (3). It has a receiving portion (5) surrounded by the bottom wall portion (51) and the side wall portion (3), and the upper end of the receiving portion (5) forms an opening (6) surrounded by the upper end of the side wall portion (3).

[0045] The main difference between the formed container (50) and the formed container (1) shown in Figs. 1 to 4 is the shape of the bottom wall portion (51) which is smaller than the opening (6) when viewed from the plane. The shape of the bottom wall portion (51) is a flat substantially 16-sided polygon that is long in the left-right direction when viewed from the plane, and has a major axis (L) extending in the left-right direction passing through the center (O) of a virtual oval (V) similar to that in Fig. 1, and a minor axis (S) orthogonal to the major axis (L) and extending in the front-rear direction passing through the center (O) of the virtual oval (V). It consists of three or more, here eight, first sides (511) formed by straight lines arranged at intervals, and the same number of second sides (512) formed by curves arranged to connect adjacent first sides (511). And the centers of the lengths of a pair of first sides (511) facing each other on the major axis (L) are located, and the centers of the lengths of a pair of first sides (511) facing each other on the minor axis (S) are located.

[0046] The first sides (511) formed by straight lines that constitute the shape of the periphery of the bottom wall portion (51) of the formed container (50) are located on the sides at intervals of a virtual 16-sided polygon having vertices on a virtual oval (V) similar to that in Fig. 1, and both ends of the first sides (511) are located on the virtual oval (V), and the second sides (512) formed by curves are located on the virtual oval (V). And adjacent sides (511)(512) are connected so as to form an obtuse angle. That is, the tangent of the end portion on the side of the first side (511) formed by a straight line in the second side (512) formed by a curve and the first side (511) formed by a straight line form an obtuse angle.

[0047] In the formed containers (40) and (50) shown in FIGS. 7 and 8, since the shape of the periphery of the bottom wall portions (41) and (51) is different from that of the formed container (1) shown in FIGS. 1 to 4, the number of ridge lines formed on the side wall portion (3) and extending upward from the vertex portions of the substantially polygon, which is the shape of the periphery of the bottom wall portions (41) and (51), and having a certain height is different from the number of ridge lines (32) of the formed container (1). Other configurations are substantially the same as those of the formed container (1) shown in FIGS. 1 to 4. When viewed from a plane, it is preferable that the distance between the periphery of the opening (6) and the periphery of the bottom wall portions (41) and (51) is 5 mm or less over the entire circumference. In this case, even if the laminate (10) is used to manufacture by press forming such as deep drawing, wrinkles and pinholes are less likely to occur in the bottom wall portions (41) and (51) and the side wall portion (3). Further, an annular step protruding inward is provided over the entire circumference at an intermediate portion in the height direction of the side wall portion (3) of the formed containers (40) and (50). The shapes of the inner and outer peripheral portions of the annular step are similar to the opening (6) when viewed from a plane and the centers are on the same vertical line as the center of the opening (6).

[0048] In all the above-described embodiments, the shape of the opening (6) of the formed containers (1), (40), and (50) is oval when viewed from a plane, but it is not limited thereto and may be circular.

[0049] Also, in all the above-described embodiments, the bottom wall portions (2), (41), and (51) have an annular step (22) that is similar to the periphery of the bottom wall portions (2), (41), and (51) when viewed from a plane and the center is the same as the center of the periphery of the bottom wall portions (2), (41), and (51) at a position having a certain distance inward from the periphery. Since the inner portion inside the annular step (22) is made slightly higher than the outer portion, the strength of the bottom wall portions (2), (41), and (51) is increased. However, even when there is no annular step (22), sufficient strength is ensured by making the shape of the periphery of the bottom wall portions (2), (41), and (51) the above-described shape, and the strength is further increased by forming the annular step (22).

Industrial Applicability

[0050] The molding container according to the present invention is suitably used in the fields of food, medical and pharmaceutical products, industry, electronic components, etc.

Explanation of Signs

[0051] (1)(40)(50): Molding container, (2)(41)(51): Bottom wall portion, (21): Side, (411)(511): First side, (412)(512): Second side, (3): Side wall portion, (31): Step portion, (4): Flange portion, (5): Accommodation portion, (6): Opening, (10): Laminate, (11): First resin layer, (12): Metal foil layer, (13): Second resin layer, (V): Virtual oval

Claims

1. A molded container formed by molding a laminate composed of a metal foil layer and a synthetic resin layer covering both sides of the metal foil layer into a cup shape, and comprising a bottom wall portion, a side wall portion integrally provided in a rising shape at the periphery of the bottom wall portion, and an outward flange portion integrally provided at the upper end of the side wall portion, and having a storage portion surrounded by the bottom wall portion and the side wall portion and an opening at the upper end of the storage portion, wherein the bottom wall portion is smaller than the opening when viewed from a plane, the shape of the opening is circular or oval when viewed from a plane, and the shape of the periphery of the bottom wall portion is a substantially polygon smaller than the opening when viewed from a plane, and adjacent sides are connected at a certain angle.

2. The molded container according to claim 1, wherein the shape of the peripheral portion of the bottom wall portion is a substantially polygon having four or more sides when viewed from a plane.

3. The molded container according to claim 1, wherein an annular step protruding inward is provided over the entire circumference at an intermediate portion in the height direction of the side wall portion, and both inner and outer peripheral edges of the annular step are similar in shape to the opening when viewed from a plane and the center is on the same vertical line as the center of the opening.

4. The molded container according to claim 1, wherein the distance between the periphery of the opening and the periphery of the bottom wall portion is 5 mm or less over the entire circumference when viewed from a plane.

5. The molded container according to claim 1, wherein the shape of the periphery of the bottom wall portion is a substantially polygon having five or more sides composed of straight lines, and all sides of the substantially polygon are located on the sides of a virtual polygon having vertices on a virtual circle or a virtual oval that is similar in shape to the opening and the center is on the same vertical line as the center of the opening.

6. The molded container according to claim 1, wherein the shape of the periphery of the bottom wall portion is composed of three or more first sides arranged at intervals and the same number of second sides composed of curves arranged to connect adjacent first sides, the first sides are located on the sides of a virtual polygon having vertices on a virtual circle or a virtual oval that is similar in shape to the opening and the center is on the same vertical line as the center of the opening, and the second sides are located on the virtual circle or the virtual oval.

7. A package, wherein the container according to any one of claims 1 to 6 contains contents in the storage portion, and the opening of the molded container is closed by a lid whose peripheral portion is heat-sealed to the flange portion.

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