Double container

Abstract

To provide a double container, which is configured so that residual liquid can be minimally suppressed and rigidity of a peripheral wall portion of a bottom part can be secured, even when the peripheral wall portion of the bottom part is formed thinner.SOLUTION: A double container comprises an inner container 12 that is reduced in volume and deformed as stored contents decrease, and an outer container 11 in which the inner container is interiorly arranged, and also comprises an outdoor air introduction hole 17 through which outdoor air is introduced to a space between the outer container and the inner container as the contents decrease, in which a mouth part 13, a trunk part 16 and a bottom part 14 are arranged along a container shaft O direction in this order from an upper side toward a lower side. The bottom part is formed in a cylindrical shape with a bottom having a peripheral wall portion 14b and a bottom wall portion 14a. A plurality of reinforcement recessed parts 21 recessed toward inside in a radial direction are formed, with an interval in a circumferential direction, over the whole length in the circumferential direction, on an outer peripheral surface of the peripheral wall portion of the bottom part.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a dual container. [Background technology]

[0002] Conventionally, as shown in Patent Document 1 below, for example, there has been known a double container which includes an inner container that reduces in volume as the contained contents decrease, and an outer container within which the inner container is placed, and which has a mouth, body, and bottom arranged in that order from top to bottom along the axial direction of the container, and which has an outside air inlet hole for introducing outside air between the outer container and the inner container as the contents decrease, and which has a bottom formed into a cylindrical shape with a peripheral wall and a bottom wall. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-18892 A Summary of the Invention [Problem to be solved by the invention]

[0004] When weight reduction is attempted for environmental reasons, the peripheral wall of the bottom portion tends to be particularly thin, which makes the peripheral wall of the bottom portion more susceptible to crushing on the filling line. In order to solve this problem, if a circumferential groove is formed in the peripheral wall of the bottom to reinforce it, the outer surface of the inner container located in this part will come into close contact with the inner surface of the outer container, making it difficult for the inner container to reduce in volume at the peripheral wall of the bottom when the contents are reduced, and there is a risk that the amount of contents that cannot be poured (residual liquid) will increase.

[0005] The present invention provides a double container capable of ensuring the rigidity of the peripheral wall of the bottom portion while keeping residual liquid to a minimum even if the peripheral wall of the bottom portion is made thin. [Means for solving the problem]

[0006] A double container according to one embodiment of the present invention comprises an inner container that reduces in volume as the contained contents decrease, and an outer container in which the inner container is fitted, and has a mouth, a body, and a bottom arranged in that order from top to bottom along the container axial direction, and an outside air inlet hole for introducing outside air between the outer container and the inner container as the contents decrease, the bottom is formed in a bottomed cylindrical shape having a peripheral wall and a bottom wall, and a plurality of reinforcing recesses that are recessed radially inward are formed at intervals in the circumferential direction along the entire circumferential length on the outer surface of the peripheral wall of the bottom.

[0007] Since a plurality of reinforcing recesses that are recessed radially inward are formed at intervals in the circumferential direction along the entire circumferential length of the outer peripheral surface of the peripheral wall of the bottom portion, it is possible to improve the rigidity of the peripheral wall of the bottom portion and ensure the rigidity of the peripheral wall of the bottom portion even if the peripheral wall of the bottom portion is made thin. Since multiple reinforcing recesses are provided at intervals in the circumferential direction, it becomes easy to provide a minute gap between the outer surface of the inner container and the inner surface of the outer container at the portions where the outer peripheral edges of the reinforcing recesses are located, and it becomes possible to prevent the outer surface of the inner container and the inner surface of the outer container from coming into close contact at the peripheral wall of the bottom. Therefore, it becomes easy to cause the inner container to undergo volumetric deformation at the peripheral wall of the bottom when the contents are reduced, and it becomes possible to prevent an increase in the amount of contents (residual liquid) that becomes impossible to pour.

[0008] The reinforcing recess may be open downward.

[0009] Since the reinforcing recess is open downward, when the contents are reduced, the inner container can be easily and reliably separated from the inner surface of the outer container at the portion where the reinforcing recess is located.

[0010] Of the inner surfaces of the reinforcing recess, a bottom surface facing radially outward may extend parallel to the container axis except for an upper end portion.

[0011] The bottom surface of the inner surface of the reinforcing recess facing radially outward extends parallel to the container axis except for the upper end portion.This makes it possible to reduce the contact area between the outer surface of the inner container and the inner surface of the outer container in the portion where the reinforcing recess is located, and ensures that the inner container can be easily separated from the inner surface of the outer container in the portion where the reinforcing recess is located when the contents are reduced. Effect of the Invention

[0012] According to the above aspect of the present invention, even if the peripheral wall of the bottom is made thin, it is possible to ensure the rigidity of the peripheral wall of the bottom while keeping the amount of residual liquid to a minimum. [Brief description of the drawings]

[0013] [Figure 1] 1 is a side view including a partial vertical cross section of a double container shown as one embodiment of the present invention, as viewed from the outside in a radial direction. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Hereinafter, a double container according to one embodiment of the present invention will be described with reference to the drawings. 1, the double container 1 according to this embodiment includes an inner container 12 that undergoes volume reduction deformation as the contained contents decrease, and an outer container 11 in which the inner container 12 is housed. The outer surface of the inner container 12 is provided so as to be separable from the inner surface of the outer container 11. In the example shown in the figure, the inner container 12 is highly flexible and is laminated on the inner surface of the outer container 11 in a manner that allows it to be peeled off. A gap may be provided between the inner surface of the outer container 11 and the outer surface of the inner container 12.

[0015] The double container 1 is formed by integrally blow molding the outer preform and the inner preform in a state where the inner preform for forming the inner container 12 is fitted into the outer preform for forming the outer container 11. In other words, the double container 1 is a biaxially stretched blow container.

[0016] The inner container 12 and the outer container 11 are made of synthetic resin material, and may be made of the same material or different materials. Examples of synthetic resin materials include PET (polyethylene terephthalate), PP (polypropylene), PE (polyethylene), nylon (polyamide), and EVOH (ethylene-vinyl alcohol copolymer).

[0017] The double container 1 has a mouth 13, a shoulder 15, a body 16, and a bottom 14. The mouth 13, the shoulder 15, the body 16, and the bottom 14 are arranged in this order coaxially with a common axis. Hereinafter, this common axis will be referred to as the container axis O, the side of the mouth 13 of the double container 1 along the container axis O will be referred to as the upper side, and the side of the bottom 14 of the double container 1 will be referred to as the lower side. The direction intersecting the container axis O as viewed from the container axis O direction will be referred to as the radial direction, and the direction going around the container axis O as viewed from the container axis O direction will be referred to as the circumferential direction.

[0018] The mouth 13 of the double container 1 is formed by stacking the mouth of the inner container 12 and the mouth of the outer container 11, the shoulder 15 of the double container 1 is formed by stacking the shoulder of the inner container 12 and the shoulder of the outer container 11, the body 16 of the double container 1 is formed by stacking the body of the inner container 12 and the body of the outer container 11, and the bottom 14 of the double container 1 is formed by stacking the bottom of the inner container 12 and the bottom of the outer container 11. In the following description, unless otherwise specified, it is assumed that both the inner container 12 and the outer container 11 have the same shape.

[0019] The size of the double container 1 in the direction of the container axis O is, for example, 115 mm or more and 220 mm or less. The capacity of the double container 1 is, for example, 150 ml or more and 600 ml or less. In the illustrated example, the size of the double container 1 in the direction of the container axis O is about 180 mm, and the double container 1 is for a capacity of 300 ml. The mouth 13 of the double container 1 is formed in a cylindrical shape extending upward from the upper end of the shoulder portion 15 . A flange portion that protrudes radially outward and extends continuously over the entire circumferential length is formed at the upper end of the mouth of the inner container 12. The flange portion is placed on the upper opening edge of the mouth of the outer container 11.

[0020] A male threaded portion 18 to which a cap (not shown) is screwed, and a sealed protrusion 19 to which a peripheral wall portion of the cap (not shown) is fitted are formed from top to bottom on the outer peripheral surface of the mouth of the outer container 11. The sealed protrusion 19 protrudes radially outward from the mouth of the outer container 11 and extends continuously over the entire circumferential length. An airtight seal is formed between the outer peripheral surface of the sealed protrusion 19 and the inner peripheral surface of the peripheral wall portion of the cap (not shown). The cap may be fitted to the mouth of the outer container 11 by undercut fitting.

[0021] An outside air introduction hole 17 is formed at the mouth of the outer container 11 to introduce outside air between the outer container 11 and the inner container 12 as the content decreases. The outside air introduction hole 17 is located at the radially outermost part of the sealed protrusion 19, and is located above the sealing surface that extends continuously over the entire circumferential length. The position where the outside air introduction hole 17 is formed is not limited to the mouth of the outer container 11, but may be, for example, the body, shoulder, or bottom of the outer container 11 other than the mouth, or may be between the upper opening edge of the mouth of the outer container 11 and the underside of the flange portion of the mouth of the inner container 12, etc.

[0022] The shoulder portion 15 extends radially outward as it goes downward from the lower end of the mouth portion 13. A plurality of vertical partition grooves 15a are formed at intervals in the circumferential direction in the shoulder portion 15. The shoulder portion 15 has a curved shape that protrudes radially outward in a vertical cross-sectional view along the container axis O.

[0023] The upper end 16a and the lower part 16b of the body 16 extend straight in the direction of the container axis O. The outer peripheral surfaces of the upper end 16a and the lower part 16b form the maximum outer diameter part of the double container 1. The outer diameter of this maximum outer diameter part is, for example, 58 mm or more and 74 mm or less. In the illustrated example, the outer diameter of the maximum outer diameter part of the double container 1 is about 66 mm.

[0024] Of the body portion 16, the size of the upper end portion 16a in the direction of the container axis O is smaller than the size of the lower portion 16b in the direction of the container axis O. A circumferential groove 16f is formed on the outer circumferential surface of the lower portion 16b of the body portion 16, extending continuously over the entire circumferential length. In the body 16, the middle portion 16c located between the upper end portion 16a and the lower portion 16b is located radially inward from the upper end portion 16a and the lower portion 16b. In the body 16, the size of the middle portion 16c in the container axis O direction is larger than the size of the lower portion 16b in the container axis O direction.

[0025] A first longitudinal groove 16d and a second longitudinal groove 16e are formed on the outer peripheral surface of the middle portion 16c of the body 16 at intervals in the circumferential direction. The first longitudinal groove 16d and the second longitudinal groove 16e are alternately provided at intervals in the circumferential direction. The first longitudinal groove 16d and the second longitudinal groove 16e are provided over the entire length of the middle portion 16c of the body 16 in the container axis O direction. The first longitudinal groove 16d and the second longitudinal groove 16e extend continuously over the entire length in the container axis O direction. The depths of the first longitudinal groove 16d and the second longitudinal groove 16e are equal to each other, and the groove width of the first longitudinal groove 16d is wider than the groove width of the second longitudinal groove 16e. The first longitudinal groove 16d and the second longitudinal groove 16e extend straight along the container axis O direction. The circumferential positions of the first longitudinal groove 16d and the longitudinal partition groove 15a of the shoulder portion 15 are aligned with each other.

[0026] The bottom portion 14 is formed in a bottomed cylindrical shape having a peripheral wall portion 14b and a bottom wall portion 14a. The peripheral wall portion 14b of the bottom portion 14 extends radially inward from the top to the bottom. The peripheral wall portion 14b of the bottom portion 14 has a curved shape that protrudes radially outward in a vertical cross-sectional view along the container axis O direction.

[0027] A plurality of (e.g., eight or more) reinforcing recesses 21 recessed radially inward are formed at intervals in the circumferential direction on the outer peripheral surface of the peripheral wall portion 14b of the bottom portion 14 over the entire circumferential length. The interval between adjacent reinforcing recesses 21 in the circumferential direction is equal to the circumferential size of the reinforcing recesses 21. In the illustrated example, the interval between adjacent reinforcing recesses 21 in the circumferential direction is slightly larger than the circumferential size of the reinforcing recesses 21. The multiple reinforcing recesses 21 are provided at equal intervals in the circumferential direction.

[0028] The reinforcing recess 21 has a rectangular shape when viewed from the outside in the radial direction, and of the four sides that define the rectangle, one pair of sides extend in the circumferential direction, and another pair of sides extend in the container axis O direction. Of the four corners that define the rectangle, the two corners located at the upper end have an R shape when viewed from the front. The sizes of the reinforcing recess 21 in the circumferential direction and the container axis O direction are equal to each other. In the illustrated example, the size of the reinforcing recess 21 in the container axis O direction is slightly larger than the size in the circumferential direction.

[0029] Of the inner surfaces of the reinforcing recess 21, the bottom surface facing radially outward extends parallel to the container axis O except for the upper end. The upper end of the bottom surface of the reinforcing recess 21 extends radially outward as it extends upward. The circumferential size at the upper edge of the bottom surface of the reinforcing recess 21 is smaller than the size of the bottom surface of the reinforcing recess 21 in the direction of the container axis O. The circumferential size of the bottom surface of the reinforcing recess 21 decreases as it extends upward.

[0030] The reinforcing recess 21 is provided over the entire peripheral wall portion 14b of the bottom portion 14 in the direction of the container axis O, except for the lower end portion. The reinforcing recess 21 is open downward. This allows the inside of the reinforcing recess 21 to be seen when viewing the double container 1 from the bottom.

[0031] As described above, according to the double container 1 of this embodiment, a plurality of reinforcing recesses 21 that are recessed radially inward are formed at intervals in the circumferential direction along the entire circumferential length on the outer peripheral surface of the peripheral wall portion 14b of the bottom portion 14. This makes it possible to improve the rigidity of the peripheral wall portion 14b of the bottom portion 14, and ensures the rigidity of the peripheral wall portion 14b of the bottom portion 14 even if the peripheral wall portion 14b of the bottom portion 14 is made thin.

[0032] Since multiple reinforcing recesses 21 are provided at intervals in the circumferential direction, it becomes easy to provide a minute gap between the outer surface of the inner container 12 and the inner surface of the outer container 11 at the portions where the outer peripheral edges, such as the circumferential ends of the reinforcing recesses 21, are located, and it becomes possible to prevent the outer surface of the inner container 12 and the inner surface of the outer container 11 from coming into close contact with each other at the peripheral wall portion 14b of the bottom 14. Therefore, it becomes easy to cause the inner container 12 to undergo volume reduction deformation at the peripheral wall portion 14b of the bottom 14 when the contents are reduced, and it becomes possible to prevent an increase in the amount of contents (residual liquid) that becomes impossible to pour.

[0033] Since the reinforcing recess 21 opens downward, when the contents are reduced, the inner container 12 can be easily and reliably separated from the inner surface of the outer container 11 at the portion where the reinforcing recess 21 is located.

[0034] Of the inner surfaces of the reinforcing recess 21, the bottom surface facing radially outward extends parallel to the container axis O except for the upper end portion. This makes it possible to reduce the contact area between the outer surface of the inner container 12 and the inner surface of the outer container 11 in the portion where the reinforcing recess 21 is located, and makes it possible to reliably separate the inner container 12 from the inner surface of the outer container 11 in the portion where the reinforcing recess 21 is located when the contents are reduced.

[0035] The technical scope of the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.

[0036] The reinforcing recess 21 may be open only radially outwardly, without opening downward. The reinforcing recess 21 may be a vertical groove extending in the container axis O direction.

[0037] In addition, within the scope of the invention, the components in the above-described embodiments may be replaced with well-known components, and the above-described embodiments and the above-described variations may be combined as appropriate. [Explanation of symbols]

[0038] 1 double container 11 Outer container 12 Inner container 13 Mouth 14 Bottom 14a Bottom wall 14b Peripheral wall part 16 Torso 17. Outside air intake 21 Reinforcement recess O Container axis

Claims

1. The container has an inner container that undergoes volume reduction deformation as the amount of content contained therein decreases, and an outer container in which the inner container is housed, and the container has a mouth, a body, and a bottom that are arranged in this order from top to bottom along an axial direction of the container, an outside air introduction hole for introducing outside air between the outer container and the inner container as the content decreases; The bottom portion is formed in a bottomed cylindrical shape having a peripheral wall portion and a bottom wall portion, The double container has a plurality of reinforcing recesses formed at intervals in the circumferential direction on the outer peripheral surface of the peripheral wall of the bottom, the reinforcing recesses being recessed radially inward along the entire circumferential length.

2. The double container according to claim 1 , wherein the reinforcing recess is open downward.

3. 3. The double container according to claim 1, wherein a bottom surface of the inner surface of the reinforcing recess facing radially outward extends parallel to the container axis except for an upper end portion.

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