JP2013159355A - Packaging container and method for manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a packaging container not losing design, even when inner pressure changes relatively to outer pressure.SOLUTION: A packaging container used for sealing and packaging a content and using paper as a portion of a material includes a bottom part, and a cylindrical side surface part higher in rigidity than the bottom part. In the outer surface part of the bottom part, a plurality of ruled lines are disposed radially when seen from the center of the bottom part. When the inner pressure of the packaging container changes relatively to outer pressure, an atmospheric pressure difference is absorbed by expansion and contraction of the bottom part, and the change of the appearance of the side surface part is suppressed.

Description

  The present invention relates to a packaging container for hermetically packaging contents and a method for manufacturing the same.

  In order to hermetically wrap contents such as instant coffee and powdered powder such as milk powder or granular materials, paper is used as a part of materials such as cup containers with sealed openings and paper beverage containers. Packaging containers are used.

  The packaging container is required to have high airtightness from the viewpoint of storage of contents. Accordingly, the packaging container is often provided with a barrier function against air or water vapor by providing an aluminum foil or a gas barrier film.

  A packaging container filled and packed with contents may be exposed to an environment in which a pressure difference occurs between the inside and the outside of the packaging container in the distribution process. For example, when a packaging container filled with contents in summer when the temperature is high is placed at a store in winter when the temperature is low, the pressure inside the packaging container is relatively lower than the outside pressure, and the packaging container There is a case where the side portion of the dent is recessed inside the packaging container and the design of the packaging container is impaired. In addition, when a packaging container filled with contents in a relatively low altitude location such as a flat ground is distributed and placed in a high altitude location, the air pressure inside the packaging container is relatively higher than the external air pressure. The side surface of the packaging container swells to the outside of the packaging container, and the design of the packaging container is impaired, and the contents may erupt due to a slight impact or the like. In order to solve the problem, it is possible to partially peel the laminated material constituting the side surface portion of the container, and in particular, when the internal pressure is reduced, the inner layer of the laminated material is peeled and swells inside the container. A container has been proposed in which the pressure drop inside the container is reduced and the side surface of the container is prevented from being dented (see, for example, Patent Document 1).

JP 2011-93614 A

  An object of this invention is to provide the packaging container which does not impair the designability, such as an external appearance, even if an internal pressure changes with respect to an external pressure. In particular, an object of the present invention is to provide a packaging container that does not impair the design of the side surface and bottom of the container.

  A packaging container according to an aspect of the present invention is a packaging container that is used for hermetically wrapping contents, and is made of paper as a part of the material, and has a cylindrical shape having a rigidity higher than that of the bottom and the bottom. A plurality of ruled lines are provided radially on the outer surface of the bottom as viewed from the center of the bottom. Moreover, it is preferable that the bulge is formed in the bottom part toward the outer side of a packaging container. Moreover, in the lower end portion folded inward of the side surface portion, among the overlapping regions with the outer edge portion of the bottom portion sandwiched, the region from the folding position to the predetermined height is sealed, and the region above this is not sealed It is preferable that an unsealed portion is provided.

  A manufacturing method of a packaging container according to an aspect of the present invention includes a step of providing a plurality of ruled lines radially from the center portion on one side of a bottom plate in which paper is used as a part of a material, and a bottom plate provided with ruled lines Fixing to the lower end side of the cylindrical side surface portion having a higher rigidity than that of the bottom plate and using paper as a part of the material so that the surface provided with the ruled line is located on the outer side. Including.

  ADVANTAGE OF THE INVENTION According to this invention, even if an internal pressure changes relatively with respect to an external pressure, the packaging container which does not impair the designability can be provided. In addition, since the rigidity of the bottom of the packaging container is made lower than the rigidity of the side surface, and by providing a plurality of ruled lines radially from the center of the bottom, it is formed so that the rigidity of the bottom is further reduced. Even if the internal pressure of the packaging container changes relative to the external pressure, the bottom can bulge or dent and the pressure change can be reduced, and the design properties such as the appearance of the packaging container are not impaired. In particular, the bottom part having a relatively low rigidity can be obtained even if the inner pressure of the packaging container filled with the contents is lowered relative to the outer pressure by causing the central part of the bottom part to bulge outside the packaging container in advance. However, since the pressure drop inside the container is reduced by being recessed inside the packaging container, the side surface portion of the packaging container is not recessed, and the design such as the appearance such as the side surface portion is not impaired. Also, by providing an unsealed part at the upper end of the fixed part that forms the outer edge of the bottom material that forms the bottom part, it is possible to prevent stress from concentrating near the outer edge of the bottom part when the bottom part is recessed inside, and in the vicinity of the outer edge No wrinkles are generated on the bottom, and the design of the bottom is not impaired.

The perspective view of the packaging container which concerns on embodiment of this invention Schematic sectional view of a packaging container according to an embodiment of the present invention The external view when the bottom part of the packaging container which concerns on embodiment of this invention is seen from the outer side of a packaging container The external view when the bottom part of the packaging container which concerns on the 1st modification of embodiment of this invention is seen from the outer side of a packaging container The external view when the bottom part of the packaging container which concerns on the 2nd modification of embodiment of this invention is seen from the outer side of a packaging container The external view when the bottom part of the packaging container which concerns on the 3rd modification of embodiment of this invention is seen from the outer side of a packaging container Schematic sectional view of the vicinity of the bottom of the packaging container according to the embodiment of the present invention The figure which shows the layer structure of the side part of the packaging container which concerns on embodiment of this invention The figure which shows the layer structure of the bottom part of the packaging container which concerns on embodiment of this invention. The figure which shows the wrinkles which arise in the bottom part of the packaging container which concerns on the subject which this invention solves The figure which shows the manufacturing method of the packaging container which concerns on embodiment of this invention. The figure which shows the relationship between the pressure of the air blowing in and the blowing time in the manufacturing method of the packaging container which concerns on embodiment of this invention.

(Embodiment)
First, the packaging container according to the present invention will be described. FIG. 1 is a perspective view of a packaging container 1 according to an embodiment of the present invention, and FIG. 2 is a schematic sectional view of the packaging container 1 taken along the line AA ′ of FIG. The outline | summary of the packaging container 1 which concerns on this embodiment is demonstrated using FIG. As shown in FIGS. 1 and 2, the packaging container 1 has a cylindrical side portion 11 and a circular bottom portion 12.

  The shape of the side part 11 is a cylindrical shape, the height of the side part 11 is 180 mm, for example, and the outer diameter of the side part 11 is 95 mm, for example. The bottom portion 12 is provided on the lower end side of the side surface portion 11. For example, the bottom portion 12 is provided at a height separated from the lower end of the side surface portion 11 by a certain distance from the upper end side. More specifically, the bottom portion 12 is provided at a height of 8 mm away from the lower end of the side surface portion 11 toward the upper end side. The outer edge of the bottom portion 12 is connected to the inner surface of the side surface portion 11. In FIG. 2, an opening is provided above the packaging container 1. However, like the conventional packaging container, the opening is sealed when the contents are stored inside the packaging container 1, whereby the packaging container 1. The inside is sealed. In the example shown in FIG. 2A, the bottom 12 forms a flat surface. In the example shown in FIG. 2B, the center portion of the bottom portion 12 swells outside the packaging container 1.

  FIG. 3 is an external view of the bottom 12 of FIG. 2 when viewed from the outside of the packaging container 1. In the example shown in FIG. 3A, twelve ruled lines 1201 are provided on the outer surface of the bottom portion 12 at regular intervals radially from the center of the bottom portion 12. In this example, the length of all ruled lines 1201 is 22 mm. In the example shown in FIG. 3B, 24 ruled lines 1201 are provided on the outer surface of the bottom portion 12 at regular intervals in a radial pattern when viewed from the central portion of the bottom portion 12. In this example, the length of all ruled lines 1201 is 12 mm. In FIG. 3, the solid line portion inside the circle is a ruled line. The number of ruled lines is counted as one ruled line formed radially when viewed from the center of the bottom 12. That is, the number of ruled lines formed symmetrically with respect to the center of the bottom portion 12 is counted as two.

  Note that the number and length of the ruled lines 1201 are not limited to the example shown in FIG. As other examples, first and second modifications are shown in FIGS. 4 and 5, respectively. FIG. 4 is an external view of the bottom 12 provided with twelve ruled lines 1201 having a length of 30 mm. FIG. 5 is an external view of the bottom 12 in which eight ruled lines 1201 having a length of 12 mm and eight ruled lines 1201 having a length of 22 mm are alternately provided at equal intervals. Further, the ruled lines need not be provided at regular intervals.

  The length of the ruled line 1201 may be 5 mm or more and less than 100 mm, and the number of the ruled line 1201 may be 6 or more and less than 30. If the length of the ruled line 1201 is shorter than this, or if the number of the ruled lines 1201 is less than this, wrinkles are likely to occur. Further, if the length of the ruled line 1201 is longer than this, or if the number of the ruled lines 1201 is larger than this, the rigidity of the bottom 12 becomes too low, and the strength as a packaging container is lowered. It is particularly preferable that the number of ruled lines 1201 is 6 or more and less than 25.

  Further, as shown in FIG. 6 as a third modified example, the outer surface portion of the bottom portion 12 has 12 ruled lines 1201 and a circular ruled line that intersects the 12 ruled lines 1201 around the center of the bottom portion 12. 1202 may be provided.

  In each example described above, the ruled line 1201 is not formed at the center of the bottom 12. However, the ruled line 1201 may pass through the center of the bottom 12.

  Moreover, in the example mentioned above, the bottom part 12 is circular shape. However, the shape of the bottom portion 12 may be a shape in which the upper and lower planes such as a regular square or a regular hexagon are polygonal. Thus, the shape of the bottom 12 is not limited to a specific shape. The side part 11 should just be connected with the outer edge of the bottom part 12 in the inner side.

  FIG. 7A is a schematic cross-sectional view of the vicinity of the bottom 12 of the packaging container 1 shown in FIG. In the example shown in FIG. 2 (a), the bottom portion 12 forms a flat surface without swelling, and only a ruled line 1201 (or a ruled line 1202) is formed. FIG. 7B is a schematic cross-sectional view of the vicinity of the bottom 12 of the packaging container 1 shown in FIG. In the example shown in FIG. 2B and FIG. 7B, the center portion of the bottom portion 12 bulges 5 mm outside the packaging container 1 with reference to the height of the outer edge of the bottom portion 12. As shown in FIGS. 2 and 7, the lower end of the side surface portion 11 is bent inward, and a flat-shaped fixing portion that can be bent is provided outside the substantial outer edge of the bottom portion 12. ing. The bottom portion 12 is fixed to the side surface portion 11 by inserting the fixing portion into a gap formed by the bent side surface portion 11 and then bonding the fixing portion and the side surface portion 11.

  FIG. 7C is a schematic cross-sectional view showing a modified example near the bottom 12 of the packaging container 1. In the example shown in FIG. 7C, the fixed portion of the outer edge of the bottom portion 12 and the side surface portion 11 sandwiching the fixing portion are bonded to the predetermined height from the bent portion of the side surface portion 11 constituting the lower end of the packaging container 1 for packaging. The sealing property of the container 1 is ensured, and an unsealed portion 130 that is not bonded is provided on the upper portion thereof. In this example, as the central portion of the bottom portion 12 swells to the outside of the packaging container 1, the unsealed portion 130 of the fixing portion at the outer edge of the bottom portion 12 is displaced inward, so that the bottom portion 12 can be easily swelled. The amount of bulging can be increased while further suppressing the generation of wrinkles that cause poor appearance. In the region where the outer edge fixing portion of the bottom portion 12 and the side surface portion 11 overlap, the height of the bonded region is preferably 1 mm to 15 mm, and particularly preferably 2 to 5 mm. Moreover, it is preferable that the height of the unsealed part 130 is 1 mm-8 mm. If the height of the unsealed part 130 is 1 mm or less, the effect of suppressing wrinkles that cause poor appearance is reduced, and if it is 8 mm or more, the material cost and production efficiency of the packaging container 1 are deteriorated.

  FIG. 8 is a diagram illustrating a layer configuration of the side surface portion 11 of FIGS. 1 and 2. As shown in FIG. 8, the side surface portion 11 has a polyethylene layer 111, a vapor deposition film 112, a polyethylene terephthalate layer 113, a paper 114, and a polyethylene layer 115 laminated in this order from the inside to the outside of the packaging container 1. Yes. Since the side surface portion 11 is composed of the resin layer, film, and paper as described above, it has rigidity and can be deformed to some extent in the thickness direction or the like.

  FIG. 9 is a diagram showing a layer configuration of the bottom 12 of FIGS. 2 and 7. As shown in FIG. 9, the bottom 12 has a polyethylene layer 121, a vapor deposition film 122, a gas barrier functional resin layer 123, a polyethylene layer 124, a paper 125, and a polyethylene layer 126 in the direction from the inside to the outside of the packaging container 1. They are stacked in this order. The gas barrier functional resin layer is, for example, an ethylene vinyl alcohol copolymer resin layer. Since the bottom portion 12 is made of the resin layer, film, and paper as described above, it has rigidity and can be deformed to some extent in the thickness direction or the like.

  In the example shown in FIG. 2B and FIG. 7B and FIG. 7C, when the bulge is formed in the bottom portion 12, the stress generated in the vicinity of the outer edge of the bottom portion 12 compresses the width of the ruled line 1201. And is dispersed throughout the bottom 12. Further, by providing the ruled line 1201, wrinkles are generated along the ruled line 1201, and the wrinkles are absorbed and become inconspicuous. As a result, the occurrence of wrinkles at the bottom 12 is suppressed, so that the design of the packaging container 1 is prevented from being impaired, and the bottom 12 can be sufficiently inflated. On the other hand, when the ruled line 1201 is not provided, stress concentrates in the vicinity of the outer edge of the bottom portion, so that a wrinkle 1001 is generated as in the bottom portion 1000 shown in FIG. 10, and the design is impaired and the swelling is insufficient. End up. In addition, in order to suppress generation | occurrence | production of a wrinkle more reliably, as shown to (c) of FIG. 7, you may provide the unsealed part 130. FIG. In addition, in the bottom portion 12 shown in FIG. 6, stress is relieved and wrinkles are absorbed by the circular ruled line 1202 in addition to the ruled line 1201.

  Moreover, since the rigidity of the bottom part 12 is lower than the rigidity of the side part 11, even if it is placed in an environment where the external pressure of the packaging container 1 is relatively higher than the internal pressure, the swelling of the bottom part 12 is reduced. Alternatively, the bottom portion 12 is recessed inside the packaging container 1 to absorb the pressure difference, while the side portion 11 whose appearance is conspicuous is not deformed, so that the design of the packaging container 1 is not impaired. As an example, the inside of the packaging container 1 was filled with instant coffee powder at 30 ° C., the opening was sealed, and the packaging container 1 was left in an environment at 0 ° C. That is, the packaging container 1 in which the contents are stored is left in an environment where the atmospheric pressure outside the packaging container 1 is relatively higher than the internal atmospheric pressure. In that case, the bulge of the bottom part 12 became small, and the side part 11 whose appearance was conspicuous was not deformed. That is, the design of the entire packaging container 1 was not impaired.

  Thus, in the example shown in FIG. 2B and FIG. 7B and FIG. 7C, the pressure difference is absorbed when the pressure inside the packaging container 1 is relatively lower than the outside pressure. For this purpose, the bottom portion 12 is previously inflated outside the packaging container. However, as shown in FIG. 2 (a) and FIG. 7 (a), if a bulge is not formed in the bottom portion 12 in advance, for example, a packaging container in which contents are packaged at a low altitude is distributed. When the air pressure inside the packaging container becomes relatively higher than the outside air pressure, such as when placed at a high altitude, the bottom 12 swells outside the packaging container without causing wrinkles, and the pressure difference is increased. Since it absorbs and suppresses the swelling of the side surface portion 11, the pressure difference can be absorbed without impairing the design of the packaging container.

  Next, the manufacturing method of the packaging container 1 which concerns on this embodiment is demonstrated. FIG. 11 is a diagram for explaining a method of manufacturing the packaging container 1. As shown in FIG. 11, in the manufacturing method of the packaging container 1 which concerns on this invention, the cylindrical receiving receptacle 2 is used. The manufacturing receptacle 2 is a container having high rigidity, and is formed of, for example, aluminum or resin. The manufacturing receptacle 2 includes a cylindrical side portion 21, a circular bottom portion 22, and a lid 23 having a hole 23 a at the center. The bottom part 22 is fixed to the lower end of the side part 21. The lid 23 is configured to be removable at the upper end of the side surface portion 21 so as to cover the opening at the upper end of the side surface portion 21.

  The inner diameter of the side part 21 of the manufacturing receiver 2 is, for example, 97 mm, and the height of the side part 21 is, for example, 180 mm. As described above, the manufacturing receptacle 2 is used when the packaging container 1 is manufactured, but before using the manufacturing receptacle 2, the following steps are executed. That is, a ruled line as shown in FIGS. 3 to 6 is provided on one plane of the bottom material 12a that will later become the bottom 12 of the packaging container 1. Specifically, a plurality of ruled lines are provided radially on one plane of the bottom member 12a as viewed from the center. And the bottom material 12a is fixed to the side part 11 at the lower end side of the side part 11 which comprises the packaging container 1. FIG. Specifically, the lower end of the side surface portion 11 is folded inward, and a fixing portion which is an outer edge portion of the bottom member 12a is sandwiched and sealed. At this time, as shown in FIG. 7 (c), the portion where the fixing portion of the bottom member 12a and the side surface portion 11 overlap is sealed from the folded position to a predetermined height, and the portion above this is not sealed. You may do it. In the present embodiment, the bottom material 12 a is fixed to the side surface portion 11 at a certain distance, for example, 8 mm away from the lower end to the upper end side of the side surface portion 11. At that time, the bottom material 12 a is fixed to the side surface portion 11 so that the surface provided with the ruled line is located on the lower end side of the side surface portion 11 and the outer edge is in contact with the inner side surface of the side surface portion 11. Since the bottom material 12a later becomes the bottom 12 of the packaging container 1, the configuration of the bottom material 12a is the same as the configuration of the bottom 12 described in the embodiment.

  Next, the entire bottom material 12a is heated to 50 ° C to 80 ° C. For example, the entire bottom material 12a is heated to 50 ° C. to 80 ° C. by applying hot air to the bottom material 12a. And the side part 11 to which the bottom material 12a was fixed is stored in the manufacturing receiver 2 so that the bottom material 12a and the bottom part 22 of the manufacturing receiver 2 face each other. For example, when the inner diameter of the side surface portion 21 of the manufacturing receiver 2 is 97 mm and the outer diameter of the side surface portion 11 constituting the packaging container 1 is 95 mm, the space between the side surface portion 21 and the side surface portion 11 is 1 mm. A space is created. After the side surface portion 11 to which the bottom material 12 a is fixed is housed in the manufacturing receptacle 2, the upper opening of the manufacturing receptacle 2 is covered with a lid 23. At that time, the hole 23 a provided in the lid 23 is arranged on the central axis of the side surface portion 21.

  Next, in the axial direction of the side surface portion 21 of the manufacturing receiver 2, air is blown into the manufacturing receiver 2 from the hole 23 a provided in the lid 23. Actually, air is blown into the space formed by the side surface portion 11, the bottom material 12 a and the lid 23 from the hole 23 a. For example, air is blown into the space from the hole 23a at a pressure of 1 MPa to 10 MPa for a period of 0.02 seconds to 10 seconds.

  Immediately before the air is blown, the entire temperature of the bottom material 12a is as high as 50 ° C. to 80 ° C. Therefore, the bottom material 12a is softened and easily deformed. By blowing air into the manufacturing receptacle 2 in this state, the center portion of the bottom material 12 a housed in the manufacturing receptacle 2 swells toward the bottom portion 22 of the manufacturing receptacle 2. For example, as described above, when air is blown at a pressure of 1 MPa or more and 10 MPa or less for a time of 0.02 seconds or more and 10 seconds or less, the center portion of the bottom material 12a swells 5 mm toward the bottom portion 22 side. When the bottom material 12a swells, the bottom material 12a becomes the bottom portion 12 shown in FIG. 1 and FIG. When the bottom portion 12 of the packaging container 1 is formed, the lid 23 is removed, and the side surface portion 11 where the bottom portion 12 is fixed on the lower end side is taken out from the inside of the manufacturing receptacle 2. Thereby, a part of packaging container 1 which has the side part 11 and the bottom part 12 which are shown in FIG. 1 can be formed.

  As described above, the bottom 12a having a ruled line on the outer surface is fixed to the lower end side of the cylindrical side surface portion 11, the upper end of the side surface portion 11 is covered with the lid 23 except for the center thereof, and the side surface covered with the lid 23 Air is blown into the inside from the outside of the upper end of the part 11. Thereby, a part of packaging container 1 which has the bottom part 12 in which the ruled line was provided, and the side part 11 to which the bottom part 12 was fixed can be manufactured. In the manufactured packaging container 1, as described above, there is no wrinkle at the bottom portion 12, and the side surface portion 11 whose appearance is conspicuous even when the internal pressure of the packaging container 1 is lowered relative to the external pressure. Since it does not dent, the design property of the whole packaging container 1 can be prevented from being impaired.

  In the above description, the example in which the bottom material 12a is heated before air is blown into the manufacturing receptacle 2 has been described. However, if the bottom material 12a has high flexibility, it is not necessary to heat the bottom material 12a. Whether to heat or not may be determined by performing an appropriate test in accordance with the flexibility of the bottom material 12a and the pressure and amount of air to be blown. The temperature for heating may be determined by conducting an appropriate test.

  In the above description, when air is blown into the manufacturing receiver 2, the hole 23 a provided in the lid 23 is inserted into the manufacturing receiver 2 in the axial direction of the side surface portion 21 of the manufacturing receiver 2. The example which blows air was demonstrated. However, it is not limited that air is blown in the axial direction of the side surface portion 21 of the manufacturing receiver 2. For example, air may be blown in a direction that forms an angle with the axis of the side surface portion 21. In short, the bottom member 12a having a ruled line on the outer surface is fixed to the lower end side of the cylindrical side portion 11, the upper end of the side portion 11 is covered with a lid provided with a hole, and the bottom What is necessary is just to blow air in the space comprised by the material 12a, the side part 11, and a lid | cover. By blowing air, the bottom material 12a swells and the bottom part of the packaging container 1 is formed.

  Moreover, in the above description, when air was blown into the manufacturing receptacle 2, an example was described in which air was blown for 0.02 seconds to 10 seconds at a pressure of 1 MPa to 10 MPa. However, the pressure of the blowing air and the blowing time are not limited to the above conditions. The pressure of the blowing air and the blowing time may be determined by appropriately performing tests according to the flexibility of the bottom material 12a, the heating condition of the bottom material 12a, and the like.

  Moreover, in the above-mentioned description, when air was blown into the manufacturing receptacle 2, the entire bottom material 12a, which later becomes the bottom 12 of the packaging container 1, was heated to 50 ° C to 80 ° C. However, a part of the bottom material 12a, for example, an area of 30% or more of the plane of the bottom material 12a may be heated to 50 ° C to 80 ° C. Even in this case, the bottom material 12a is soft and easily deformed. Therefore, by blowing air into the manufacturing receptacle 2 in this state, the bottom material 12a housed in the manufacturing receptacle 2 has a central portion on the bottom 22 side of the manufacturing receptacle 2. Swell.

  Moreover, in the above-mentioned description, the example of the manufacturing method of the packaging container 1 which has the circular bottom part 12 and the cylindrical side part 11 corresponding to it was demonstrated. However, this manufacturing method can also be applied to the manufacture of a packaging container having a bottom 12 having a shape other than a circular shape.

  Moreover, in the above-mentioned description, the example which forms the bottom part 12 which comprises a part of packaging container 1 by inflating the center part of the bottom material 12a by blowing in air was demonstrated. However, the bottom portion 12 may be formed by inflating the central portion of the bottom material 12a using a male mold and a female mold.

  The step of forming the bulge of the bottom portion 12 may be performed continuously from the other steps. However, in order to ensure that the bulge of the bottom 12 is maintained when the packaging container 1 is sealed, the bulge of the bottom 12 may be formed immediately before the packaging container 1 is filled with the contents. Alternatively, the step of forming the bulge of the bottom portion 12 is carried out continuously after the other steps, and the bottom portion 12 is sucked from the outside of the packaging container 1 immediately before filling the contents, etc. Even if the bulge is recessed, the bulge may be restored.

Examples in which the present invention is specifically implemented will be described below.
Example 1
Regarding the bottom 12 of the packaging container 1, the internal pressure of the packaging container 1 is relatively lower than the external atmospheric pressure when the ruled line is not provided and when the ruled line shown in FIGS. 3 to 6 is provided. Then, when the bottom portion was recessed, it was determined whether or not wrinkles occurred in the vicinity of the outer edge of the bottom portion. The determination results are as shown in “Defect appearance defect” in Table 1 below. In the column, “◯” is described when no wrinkle occurs, and “X” is described when wrinkle occurs. In Table 1, the amount of swelling with respect to the outer edge of the central portion of the bottom portion 12 is shown as “bulging depth”. The swelling of the bottom 12 was formed by blowing air at 1 MPa for 0.2 seconds using the above-described manufacturing method.

  As shown in Table 1, wrinkles occurred in the vicinity of the outer edge of the bottom at the bottom where no ruled line was provided. On the other hand, no wrinkles occurred near the outer edge of the bottom at the bottom where the ruled lines shown in FIGS. As described above, if a ruled line is provided on the outer surface portion of the bottom portion 12, a design is provided in the vicinity of the outer edge of the bottom portion 12 even when the pressure inside the packaging container 1 is relatively lower than the outside pressure and the bottom portion 12 is recessed. It was found that there was no wrinkle that impairs sex.

(Example 2)
Regarding this manufacturing method, the relationship between the pressure of the air to be blown and the blowing time when air was blown to the center of the bottom material 12a to form the bottom 12 having a bulge of 3 mm at the center was determined. The determination result is as shown in FIG. As shown in FIG. 12, it was found that the bottom 12 having a bulge of 3 mm at the center could be formed by blowing air at a pressure of 1 MPa to 10 MPa for a time of 0.02 seconds to 10 seconds.

  In the above-described manufacturing method, as shown in FIG. 2B and FIG. 7B and FIG. 7C, the case where the bulge is formed in advance on the outside of the packaging container has been described. As shown in FIGS. 2A and 7A, when the bulge is not formed in the bottom portion 12 in advance, the step of heating the entire bottom member 12a and the step of expanding the central portion of the bottom member 12a. Can be omitted.

  INDUSTRIAL APPLICABILITY The present invention can be used for a packaging container for hermetically packaging contents such as powder (granular).

DESCRIPTION OF SYMBOLS 1 Packaging container 11 Side part 12 Bottom part 111 Polyethylene layer 112 Deposition film 113 Polyethylene terephthalate layer 114 Paper 115 Polyethylene layer 121 Polyethylene layer 122 Deposition film 123 Gas barrier functional resin layer 124 Polyethylene layer 125 Paper 126 Polyethylene layer 130 Unsealed part 1201, 1202 Ruled line 2 Receiving tool 21 Side part 22 Bottom part 23 Lid 23a Hole 12a Bottom material 1000 Bottom part 1001

Claims (14)

A packaging container that is used for hermetically wrapping the contents, and paper is used as part of the material,
The bottom,
A cylindrical side surface portion having rigidity higher than the rigidity of the bottom portion,
A packaging container in which a plurality of ruled lines are provided radially on the outer surface of the bottom as viewed from the center of the bottom.   The said bottom part is a packaging container in which the swelling is formed toward the outer side of the said packaging container. The outer edge of the bottom and the lower end of the side are
In a state where the lower end portion of the side surface portion is folded inward and sandwiches the outer edge portion of the bottom portion, they overlap,
The packaging container according to claim 1 or 2, wherein an area from the folding position to a predetermined height in the overlapping area is sealed, and an unsealed portion is provided in which the area above the area is not sealed.   The packaging container according to claim 1, wherein the ruled lines are provided at equal intervals.   The packaging container according to any one of claims 1 to 4, wherein a length of the ruled line is 5 mm or more and less than 100 mm.   The packaging container according to any one of claims 1 to 5, wherein the number of ruled lines is 6 or more and less than 30.   The bottom portion is made of a material in which a polyethylene layer, a vapor deposition film, a gas barrier functional resin layer, a polyethylene layer, paper, and a polyethylene layer are laminated in this order from the inside to the outside of the packaging container. The packaging container in any one of 6.   The said side part consists of the material in which the polyethylene layer, the vapor deposition film, the polyethylene terephthalate layer, paper, and the polyethylene layer were laminated | stacked in this order from the inner side to the outer side of the said packaging container. A packaging container according to 1. A step of providing a plurality of ruled lines radially when viewed from the center on one side of the bottom plate in which paper is used as a part of the material;
A cylindrical side surface portion having a rigidity higher than that of the bottom plate and using paper as a part of the material so that the surface on which the ruled line is provided is located outside the bottom plate provided with the ruled line. And a step of fixing to the lower end side of the packaging container. A step of covering a part of an opening at an upper end of the side surface portion to which the bottom plate is fixed, and a part of the opening to blow air into a space formed by the bottom plate and the side surface portion. The method for manufacturing a packaging container according to claim 9, further comprising a step of inflating the central portion. The step of fixing the bottom plate to the lower end side of the side surface portion,
The lower end portion of the side surface portion is folded inward at the lower end portion of the side surface portion, and the outer edge portion of the bottom plate is sandwiched therebetween,
The manufacturing method of the packaging container of Claim 9 or 10 including the process of sealing the area | region from the folding position to predetermined | prescribed height among the said overlapping area | regions, and not sealing the area | region above this.   The manufacturing method of the packaging container of Claim 10 or 11 which further includes the process of heating the said bottom part to 50 to 80 degreeC before the process of inflating the said center part of the said baseplate.   The method for manufacturing a packaging container according to any one of claims 10 to 12, wherein, in the step of covering the opening at the upper end of the side surface part while leaving a part, the opening is covered while leaving a center part of the opening.   The method for manufacturing a packaging container according to any one of claims 10 to 13, wherein when air is blown into the space, air is blown at a pressure of 1 MPa to 10 MPa for a time of 0.02 seconds to 10 seconds.

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