JP7650774B2 - Double container - Google Patents

Description

The present invention relates to a double container.

Conventionally, as shown in, for example, Patent Document 1 below, there has been known a double container that includes an inner container that reduces in volume as the contained contents decrease, and an elastically deformable outer container in which the inner container is placed, and in which the mouth, shoulder, body, and bottom are arranged in that order from top to bottom along the bottle axial direction, and which has an outside air introduction hole that introduces outside air between the outer container and the inner container as the contents decrease.

JP 2019-131256 A

However, with the conventional double-walled containers, there was room for improvement in terms of increasing the restoring force of the outer container without impeding smooth separation of the inner container from the inner surface of the outer container.

The present invention was made in consideration of the above-mentioned circumstances, and aims to provide a double container that can increase the restoring force of the outer container without impeding smooth separation of the inner container from the inner surface of the outer container.

The double container of the present invention comprises an inner container which undergoes volume reduction deformation as the contained contents decrease, and an elastically deformable outer container in which the inner container is housed, and in which a mouth, a shoulder, a body, and a bottomed cylindrical bottom are arranged in this order from top to bottom along the bottle axial direction, and an outside air introduction hole is provided for introducing outside air between the outer container and the inner container as the contents decrease, and a circumferential groove is formed in the body which is recessed radially inward and extends in the circumferential direction, and a vertical convex portion is formed on the inner surface of the circumferential groove which divides the circumferential groove in the circumferential direction. The lower end of the body portion, when viewed from the radial outside, presents a curved shape that protrudes radially outward, and the lower part of the body portion excluding the lower end portion presents a curved shape that recesses radially inward when viewed from the radial outside, the peripheral wall portion of the bottom portion extends radially inward as it extends downward, the outer circumferential surface of the lower end portion of the body portion is the maximum outer diameter portion of the double container, and the circumferential groove is provided at the lower end portion of the body portion, and the circumferential groove is provided over the entire length of the lower end portion of the body portion in the bottle axial direction .

Since a circumferential groove is formed in the body portion, it is possible to increase the rigidity of the body portion of the outer container, and after an external force is applied to the body portion and the body portion is squeezed and deformed radially inward, the body portion of the outer container can be smoothly restored to its original shape when this external force (pressing force) is released.
Since a vertical convex portion is formed on the inner surface of the circumferential groove, dividing the circumferential groove in the circumferential direction, outside air introduced between the inner container and the outer container from the outside air inlet hole can easily pass up and down through the vertical convex portion, making it easier to peel the inner container from the inner surface of the outer container at the circumferential groove starting from the vertical convex portion. This allows the inner container, including the portion where the circumferential groove is provided, to be smoothly peeled from the inner surface of the outer container as the contained contents decrease.

The outer surface of the vertical convex portion facing radially outward may be connected without any step in the vertical direction to the outer peripheral surface of each portion of the double container that is connected in the vertical direction to the circumferential groove.

The outer surface of the vertical convex portion that faces radially outward is connected without any steps in the vertical direction to the outer peripheral surface of each part of the double container that is connected vertically to the circumferential groove, so that outside air introduced between the inner container and the outer container from the outside air inlet hole can easily and reliably pass through the vertical convex portion.

At least the lower portion of the body portion may extend radially outward as it extends downward, and the circumferential groove may be provided in the lower portion of the body portion.

A circumferential groove is provided in the lower part of the body, which extends radially outward as it goes downward and makes it difficult for the outer container to restore its original shape after squeeze deformation, thereby increasing the rigidity of the lower part of the body of the outer container and making it easier for the lower part of the body of the outer container to restore its original shape after squeeze deformation.
Since the vertical convex portion is formed on the inner surface of the circumferential groove, it is possible to ensure smooth peeling of the inner container from the inner surface of the outer container at the lower part of the body.

This invention makes it possible to increase the restoring force of the outer container without impeding smooth peeling of the inner container from the inner surface of the outer container.

FIG. 2 is a side view including a partial vertical cross section of a double container shown as one embodiment, as viewed from the outside in the radial direction.

Hereinafter, a double container according to one embodiment 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 elastically deformable 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 illustrated example, the inner container 12 is highly flexible and is laminated on the inner surface of the outer container 11 in a manner that allows the inner container 12 to be peeled away from the inner surface of the outer container 11.
In addition, a gap may be provided between the inner surface of the outer container 11 and the outer surface of the inner container 12.

The double container 1 is formed by integrally blow molding the outer preform and the inner preform, with the inner preform for forming the inner container 12 fitted into the outer preform for forming the outer container 11. In other words, the double container 1 is a biaxially stretched blown container.

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).
In the illustrated example, the inner container 12 and the outer container 11 are each made of PET (polyethylene terephthalate).

The double container 1 includes 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 bottle axis O, the side of the mouth 13 of the double container 1 along the bottle 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. When viewed from the bottle axis O direction (up-down direction), the direction intersecting the bottle axis O will be referred to as the radial direction, and the direction going around the bottle axis O will be referred to as the circumferential direction.

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.

The size of the double container 1 in the direction of the bottle 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 bottle axis O is approximately 150 mm, and the double container 1 is for a capacity of 200 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.

On the outer peripheral surface of the mouth of the outer container 11, there are formed, in this order from top to bottom, a locking protrusion 18 to which a cap (not shown) is locked, a sealed protrusion 19 to which the peripheral wall portion of the cap (not shown) is fitted, and a neck ring 20.
The locking projection 18, the sealed projection 19, and the neck ring 20 project radially outward from the mouth of the outer container 11 and extend continuously over the entire circumferential length. An airtight seal is formed between the outer peripheral surface of the sealed projection 19 and the inner peripheral surface of the peripheral wall of the cap (not shown). The outer diameter of the neck ring 20 is larger than the outer diameter of the sealed projection 19.
The cap may be screwed onto the mouth of the outer container 11. The neck ring 20 does not need to be provided.

An outside air introduction hole 17 for introducing outside air between the inner container 12 as the contents decrease is provided above the shoulder portion 15. In the illustrated example, the outside air introduction hole 17 is formed in the mouth of the outer container 11. 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 it 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.

The shoulder portion 15 extends radially outward from the lower end of the mouth portion 13 downward.
At least the lower part of the body 16 extends radially outward as it goes downward. In the illustrated example, the upper part of the body 16 extends almost straight in the bottle axis O direction. The lower part of the body 16, except for the lower end 16a, is curved and recessed radially inward when viewed from the outside in the radial direction. The lower end 16a of the body 16 is curved and protrudes radially outward when viewed from the outside in the radial direction. The outer peripheral surface of the lower end 16a of the body 16 is the maximum outer diameter part with the largest outer diameter in 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 62 mm. The body 16 may extend radially outward as it goes from the top to the bottom over the entire length in the bottle axis O direction. The lower part of the body portion 16, the lower end portion 16a of the body portion 16, and the portion of the lower part of the body portion 16 excluding the lower end portion 16a may extend in a straight line or in a curved line when viewed from the outside in the radial direction.
The bottom 14 is formed in a bottomed cylindrical shape. The peripheral wall portion 14b of the bottom 14 extends radially inward as it extends downward. The bottom 14 has a circular shape over its entire length in the bottle axis O direction when viewed in a cross section perpendicular to the bottle axis O.

At least the body of the outer container 11 is capable of being squeezed (elastically deformed), and the inner container 12 shrinks and deforms in response to the squeeze deformation of the outer container 11. The body 16, shoulder 15, and bottom 14 are connected without any steps in the direction of the bottle axis O.

The body 16 and shoulder 15 are configured by connecting multiple surfaces 31 in the circumferential direction via corners 32. In the illustrated example, the body 16 and shoulder 15 have a regular hexagonal shape in the cross section. The shoulder 15 may have, for example, a circular or elliptical shape in the cross section.

The surface portion 31 has a curved shape that protrudes radially outward in a cross section perpendicular to the bottle axis O. The surface portion 31 may have a straight shape in the cross section.
When viewed from the outside in the radial direction, the corner portion 32 is formed in a ridge shape extending in the direction of the bottle axis O. In addition, when viewed from the outside in the radial direction, the corner portion 32 may be formed in a band shape having a circumferential width and extending in the direction of the bottle axis O.

A first vertical convex rib 33 is formed on the corner 32 and extends in the direction of the bottle axis O when viewed from the outside in the radial direction. The first vertical convex rib 33 does not necessarily have to be provided.

The first vertical convex rib 33 is formed separately at each of the multiple corners 32. The first vertical convex rib 33 extends straight in the bottle axis O direction when viewed from the outside in the radial direction. The width of the first vertical convex rib 33 is wider than the width of the corners 32. The first vertical convex rib 33 is integrally formed from the connection portion (hereinafter referred to as the lower end) 13a with the shoulder portion 15 of the mouth portion 13, through the shoulder portion 15, and to the center of the body portion 16 in the bottle axis O direction. In other words, the upper end of the first vertical convex rib 33 is located at the lower end 13a of the mouth portion 13, and the lower end of the first vertical convex rib 33 is located at the center of the body portion 16 in the bottle axis O direction.

Here, the lower end 13a of the mouth portion 13 is located below the neck ring 20 and is a boundary portion that stretches during blow molding. At the lower end 13a of the mouth portion 13, an upper gap is provided between the outer container 11 and the inner container 12. The upper gap is provided intermittently over the entire circumferential length. This upper gap is also provided in a state in which the inner preform for forming the inner container 12 is fitted into the outer preform for forming the outer container 11 before the double container 1 becomes a biaxially stretched blow container. In addition, a configuration in which multiple vertical ribs are formed at intervals in the circumferential direction on the outer peripheral surface of the upper part of the inner preform, and the upper gap is provided intermittently over the entire circumferential length by the multiple vertical ribs may be adopted. The upper gap may extend continuously over the entire circumferential length.

The protruding height of the portion of the first vertical convex rib 33 located between both ends in the bottle axis O direction is uniform over the entire length in the bottle axis O direction, and the protruding height of both ends in the bottle axis O direction decreases toward the outside in the bottle axis O direction. The width of the portion of the first vertical convex rib 33 located between both ends in the bottle axis O direction is uniform over the entire length in the bottle axis O direction, and the width of both ends in the bottle axis O direction decreases toward the outside in the bottle axis O direction. The first vertical convex rib 33 has a convex curved shape when viewed in cross section.

In the shoulder portion 15, a vertical groove 34 is formed in the portion located between the first vertical protruding ribs 33 adjacent to each other in the circumferential direction, extending in the direction of the bottle axis O when viewed from the outside in the radial direction. Note that the vertical groove 34 does not have to be provided.

The vertical groove 34 extends straight in the direction of the bottle axis O when viewed from the outside in the radial direction. The upper end of the vertical groove 34 is located below the lower end 13a of the mouth portion 13. The vertical groove 34 is integrally formed from the upper end of the shoulder portion 15 to the upper end of the body portion 16. The vertical groove 34 may be formed only in the shoulder portion 15. The width of the vertical groove 34 is wider than the width of the first vertical convex rib 33. The width of the vertical groove 34 may be less than the width of the first vertical convex rib 33.

The depth of the vertical groove 34 between both ends in the bottle axis O direction is uniform over the entire length in the bottle axis O direction, and the depth of both ends in the bottle axis O direction becomes shallower toward the outside in the bottle axis O direction. The width of the vertical groove 34 between both ends in the bottle axis O direction is uniform over the entire length in the bottle axis O direction, and the width of both ends in the bottle axis O direction becomes narrower toward the outside in the bottle axis O direction. A plurality of vertical grooves 34 are formed at intervals in the circumferential direction on the surface portion 31. One vertical groove 34 is formed in the circumferential center of the surface portion 31. The inner surface of the vertical groove 34 has a concave curved shape when viewed in cross section.

Between the first vertical convex ribs 33 adjacent to each other in the circumferential direction, a second vertical convex rib 35 is formed, which extends in the direction of the bottle axis O when viewed from the outside in the radial direction. Note that the second vertical convex rib 35 does not have to be provided.

The second vertical convex rib 35 extends straight in the direction of the bottle axis O when viewed from the outside in the radial direction. The second vertical convex rib 35 is formed integrally with the shoulder portion 15 and the body portion 16. The length of the second vertical convex rib 35 is shorter than the length of the first vertical convex rib 33. The lower end of the second vertical convex rib 35 is located below the lower end of the vertical groove 34 and above the lower end of the first vertical convex rib 33. The positions of the upper ends of the second vertical convex rib 35 and the first vertical convex rib 33 in the direction of the bottle axis O are the same.

The protruding height of the second vertical convex rib 35 is equal to the protruding height of the first vertical convex rib 33. The protruding heights of the second vertical convex rib 35 and the first vertical convex rib 33 may be different from each other. The width of the second vertical convex rib 35 is narrower than the width of the first vertical convex rib 33. The width of the second vertical convex rib 35 may be greater than or equal to the width of the first vertical convex rib 33.

The protruding height of the portion of the second vertical convex rib 35 located between both ends in the bottle axis O direction is uniform over the entire length in the bottle axis O direction, and the protruding height of both ends in the bottle axis O direction decreases toward the outside in the bottle axis O direction. The width of the portion of the second vertical convex rib 35 located between both ends in the bottle axis O direction is uniform over the entire length in the bottle axis O direction, and the width of both ends in the bottle axis O direction decreases toward the outside in the bottle axis O direction. The second vertical convex rib 35 has a convex curved shape when viewed in cross section.

The vertical grooves 34 and the second vertical convex ribs 35 are alternately provided in the circumferential direction on the surface portion 31. At least one of the multiple vertical grooves 34 provided on one surface portion 31 is provided between a first vertical convex rib 33 and a second vertical convex rib 35 that are adjacent to each other in the circumferential direction. The first vertical convex rib 33, the vertical grooves 34, and the second vertical convex rib 35 are provided in a row in the circumferential direction.
The first vertical convex rib 33 and the second vertical convex rib 35 may be adjacent to each other in the circumferential direction without the vertical groove 34. The first vertical convex rib 33, the vertical groove 34, and the second vertical convex rib 35 may be provided at intervals in the circumferential direction.

In this embodiment, a circumferential groove 21 is formed in the body 16, which is recessed radially inward and extends circumferentially. The inner surface of the circumferential groove 21 has a curved shape recessed radially inward in a vertical cross-sectional view along the bottle axis O. A vertical protrusion 22 is formed on the inner surface of the circumferential groove 21, dividing the circumferential groove 21 in the circumferential direction. A plurality of vertical protrusions 22 are provided at intervals in the circumferential direction. The plurality of vertical protrusions 22 are provided at equal intervals over the entire circumferential length of the circumferential groove 21. The vertical protrusions 22 are formed in a rectangular parallelepiped shape that is long in the bottle axis O direction.

In the illustrated example, the circumferential groove 21 is provided in the lower part of the body 16. The circumferential groove 21 is provided in the lower end 16a of the body 16. The circumferential groove 21 is provided over the entire length of the lower end 16a of the body 16 in the direction of the bottle axis O.

The vertical convex portion 22 is defined by an outer surface facing radially outward and a pair of side surfaces connecting both circumferential ends of the outer surface to the inner surface of the circumferential groove 21. The side surfaces of the vertical convex portion 22 extend in a circumferential direction away from each other as they move radially inward. The outer surface of the vertical convex portion 22 is seamlessly connected in the bottle axis O direction to the outer peripheral surfaces of each portion of the double container 1 that is connected to the circumferential groove 21 in the bottle axis O direction. The upper end of the outer surface of the vertical convex portion 22 is seamlessly connected to the outer peripheral surface of the body portion 16, and the lower end of the outer surface of the vertical convex portion 22 is seamlessly connected to the outer peripheral surface of the peripheral wall portion 14b of the bottom portion 14.

As described above, according to the double container 1 of this embodiment, the circumferential groove 21 is formed in the body 16, which makes it possible to increase the rigidity of the body of the outer container 11. When an external force is applied to the body 16, the body 16 is squeezed radially inward and deformed, and then this external force (pressing force) is released, the body of the outer container 11 can be smoothly restored to its original shape.

A vertical convex portion 22 is formed on the inner surface of the circumferential groove 21, dividing the circumferential groove 21 in the circumferential direction, so that outside air introduced between the inner container 12 and the outer container 11 from the outside air inlet 17 can easily pass through the vertical convex portion 22 in the direction of the bottle axis O, making it easier to peel the inner container 12 from the inner surface of the outer container 11 at the circumferential groove 21 starting from the vertical convex portion 22. This allows the inner container 12, including the portion where the circumferential groove 21 is provided, to be smoothly peeled from the inner surface of the outer container 11 as the contained contents decrease.

The outer surface of the vertical protrusion 22 facing radially outward is connected without any steps in the bottle axis O direction to the outer peripheral surface of each part of the double container 1 that is connected to the circumferential groove 21 in the bottle axis O direction, so that outside air introduced between the inner container 12 and the outer container 11 from the outside air introduction hole 17 can easily and reliably pass through the vertical protrusion 22 in the bottle axis O direction.

A circumferential groove 21 is provided in the lower part of the body 16, which extends radially outward as it goes downward and where the outer container 11 is less likely to undergo restoration deformation after squeeze deformation, thereby increasing the rigidity of the lower part of the body of the outer container 11 and making it easier for the lower part of the body of the outer container 11 to undergo restoration deformation after squeeze deformation.
Since the vertical convex portion 22 is formed on the inner surface of the circumferential groove 21 , smooth peeling of the inner container 12 from the inner surface of the outer container 11 can be ensured at the lower part of the body portion 16 .

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.

A step may be provided between the outer surface of the vertical convex portion 22 and the outer peripheral surface of each portion of the double container 1 that is connected to the circumferential groove 21 in the bottle axis O direction.
The vertical convex portion 22 may be formed, for example, in a cubic shape.
The body 16 may extend straight in the bottle axis O direction over its entire length in the bottle axis O direction.

In addition, the components in the above embodiment may be replaced with well-known components as appropriate without departing from the spirit of the present invention, and the above embodiment and the above modified examples may be combined as appropriate.

Reference Signs List 1 Double container 11 Outer container 12 Inner container 13 Mouth 14 Bottom 15 Shoulder 16 Body 17 Outside air introduction hole 21 Circumferential groove 22 Vertical convex portion

Claims (3)

The bottle has an inner container that is deformed to reduce its volume as the amount of content contained therein decreases, and an outer container that is elastically deformable and has the inner container housed therein, and the bottle has a mouth, a shoulder, a body, and a cylindrical bottom with a bottom, which are arranged in this order from top to bottom along the bottle axial direction,
A double container having an outside air introduction hole for introducing outside air between the outer container and the inner container as the contents decrease,
A circumferential groove is formed in the body portion, the circumferential groove being recessed radially inward and extending in a circumferential direction,
A vertical convex portion is formed on the inner surface of the circumferential groove so as to divide the circumferential groove in the circumferential direction ,
The lower end of the body portion has a curved shape that protrudes radially outward when viewed from the outside in the radial direction,
A portion of the lower part of the body portion excluding a lower end portion has a curved shape recessed toward the inside in the radial direction when viewed from the outside in the radial direction,
The peripheral wall portion of the bottom portion extends radially inward as it extends downward,
The outer circumferential surface of the lower end of the body is the largest outer diameter portion in the double container,
The circumferential groove is provided at a lower end of the body portion,
The double container has a circumferential groove provided over the entire length of the lower end of the body in the axial direction of the bottle . The double container according to claim 1, wherein the outer surface of the vertical convex portion facing radially outward is connected without any step in the vertical direction to the outer peripheral surface of each portion of the double container that is connected in the vertical direction to the circumferential groove. At least a lower portion of the body portion extends radially outward as it extends downward,
3. The double container according to claim 1, wherein the circumferential groove is provided in a lower part of the body portion.

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