Double container

Abstract

To provide a double container capable of achieving a feeling of use on par with that of a container with a valve member in an atmospheric introduction hole, and moreover, reducing the number of parts, and reducing manufacturing costs.SOLUTION: The double container includes an outer layer and an inner layer. The inner layer shrinks as the contents contained in the inner layer decrease. The double container has a body portion and a mouth portion outer dimension of which is smaller than that of the body portion and having a discharge port. In the mouth portion, an atmospheric introduction hole without a valve is formed on an outer layer. For example, the mouth portion has an annular recess, and the atmospheric introduction hole is formed in the annular recess. A closure cap is attached to the mouth portion.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to a double container in which the inner layer shrinks as the content is dispensed, and in particular to a double container in which an air inlet hole having no valve is formed at the mouth. [Background technology]

[0002] Conventionally, double containers (so-called peelable laminated containers) have been proposed that have an outer container and an inner bag, and the inner bag shrinks as the contents decrease (see, for example, Patent Documents 1 and 2). In a double container of this configuration, the inner bag shrinks as the contents decrease, so air does not get into the inner bag, minimizing contact of the contents with air, and thus preventing oxidation and deterioration.

[0003] In the double container, it is necessary to introduce air between the outer container and the inner bag, and therefore it is common to form an air introduction hole in the outer container and provide a valve member to regulate the flow of air in and out of the air introduction hole. In the peelable laminate containers of Patent Documents 1 and 2, a recess is formed in the shoulder of the container, and an air introduction hole penetrating only the outer shell (outer container) is formed in this recess, and a valve member is attached to it. The valve member is attached to the air introduction hole formed in the outer shell of the container body, and the air introduction hole is opened and closed by the relative movement of this valve member with respect to the container body. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2017-154802 A [Patent Document 2] JP 2017-193342 A Summary of the Invention [Problem to be solved by the invention]

[0005] The aforementioned double-walled containers reduce contact between the contents and air and can minimize the effects of oxidation, etc.; however, they are made up of three parts - the double-walled container body, the outside air intake valve, and the cap - and have a large number of parts, which poses a major challenge as it increases costs compared to regular plastic containers.

[0006] The present invention has been made in consideration of the above-mentioned conventional circumstances, and aims to provide a double container that can reduce the number of parts and reduce manufacturing costs while ensuring sufficient performance. [Means for solving the problem]

[0007] In order to achieve the above-mentioned object, the double container of the present invention has an outer layer and an inner layer, and the inner layer shrinks as the content contained in the inner layer decreases, and has a body and a mouth portion having an outer dimension smaller than that of the body portion and having a discharge port, and an air introduction hole having no valve is formed in the outer layer at the mouth portion, and a stopper-type cap is attached to the mouth portion, and the air introduction hole is closed by the cap. The air inlet is not covered, and the opening diameter d of the air inlet is 1.0 mm to 1.5 mm. The air inlet is formed at a position 180° opposite to the hinge of the cap. Alternatively, the present invention is a double container having an outer layer and an inner layer, the inner layer shrinking as the content contained in the inner layer decreases, the double container having a body and a mouth having an outer dimension smaller than that of the body and having a discharge port, the mouth having an air introduction hole without a valve formed in the outer layer, the mouth having an annular recess, the air introduction hole being formed in the annular recess, a cap of a stopper type being attached to the mouth, and the annular recess being provided for gripping by a stoppering machine when the cap is stopped up on the mouth. The opening diameter d of the air introduction hole is 1.0 mm to 1.5 mm, and the air introduction hole is formed at a position 180° opposite to the hinge of the cap. It is characterized by:

[0008] The inventors of the present invention have found that in a double container in which the mouth is facing downwards and the contents are discharged, the feel of use differs depending on the position of the air inlet. After further investigation, the inventors have found that by forming an air inlet in the mouth, particularly in the area near the base end (the so-called neck), a feel of use comparable to that of a container with a valve member can be achieved.

[0009] The double container of the present invention has been devised based on such knowledge. In the double container of the present invention, when the mouth is tilted downward and the contents are discharged by so-called squeezing, a pressing force is applied to the inside of the inner layer by the squeezing force and the weight of the contents, and the inner layer is pressed against the outer layer. As a result, the inner layer is in close contact with the air introduction hole formed in the outer layer and in a sealed state, and the contents are smoothly discharged by squeezing. After discharging, when the squeezing force is released and the double container is returned to the upright state, the pressing force applied to the inner layer is released, the inner layer is quickly peeled off from the outer layer, and air (outside air) is quickly introduced between the inner layer and the outer layer. Effect of the Invention

[0010] According to the present invention, it is possible to provide a double container that can provide a usability comparable to that of a container provided with a valve member in the atmosphere inlet, while also reducing the number of parts and manufacturing costs. [Brief description of the drawings]

[0011] [Figure 1] FIG. 2 is a schematic front view of the container body of the double container. [Diagram 2] FIG. 2 is a schematic side view showing the state in which the cap is attached to the container body. [Diagram 3] 3 is a schematic cross-sectional view of the vicinity of the mouth of the container body. FIG. [Figure 4] 3 is a schematic cross-sectional view of the vicinity of the mouth of a container body with a cap attached. FIG. [Diagram 5] 2 is a schematic front view showing an enlarged view of the vicinity of the mouth of the container body. FIG. [Figure 6] 1A is a schematic cross-sectional view of the main part showing the state in which the contents are being ejected, and FIG. 1B is a schematic cross-sectional view of the main part showing the state in which the double container is returned to the upright position. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, an embodiment of a double container to which the present invention is applied will be described with reference to the drawings.

[0013] As shown in Fig. 1, the double container 1 of this embodiment mainly comprises a container body 2 equipped with a storage section (body) 3 for storing the contents and a mouth section 4 having an opening 4a for discharging the contents from the storage section 3. In this embodiment, the storage section 3 is shaped to have a shoulder section, and is shaped to have the mouth section 4 beyond the shoulder section. The outer dimensions of the mouth section 3 are smaller than those of the storage section 3.

[0014] A cap 5 is attached to the mouth 4 of the container body 2 as shown in Fig. 2, and the content of the container body 2 is discharged from a discharge port provided in the cap 5. Fig. 2 is a side view of the container body 2 rotated 90° from the state shown in Fig. 1.

[0015] The double container 1 of this embodiment is a so-called laminated peelable container, and as shown in Figure 3, the container body 2 has an outer layer 11 which is an outer shell and an inner layer 12 which is an inner bag in the storage section 3 and the mouth section 4, and the inner layer 12 shrinks as the contents decrease.

[0016] The outer layer 11 and the inner layer 12 are, for example, subjected to blow molding as a multi-layer parison and molded in an integrally bonded state, but the form of use is, for example, to peel (preliminary peel) the inner layer 12 from the outer layer 11 in advance, except for the mouth portion 4, before use, fill the container with contents until the inner layer 12 comes into contact with the outer layer 11, and push out the contents, thereby causing the inner layer 12 to shrink. Alternatively, the inner layer 12 may be left bonded to the outer layer 11, and the inner layer 12 may be peeled off from the outer layer 11 and shrink as the contents are discharged.

[0017] To further explain the layer structure of the container body 2, as described above, the container body 2 has an outer layer 11 and an inner layer 12, and the outer layer 11 is formed thicker than the inner layer 12 so as to have high restorability.

[0018] The outer layer 11 is composed of, for example, low-density polyethylene, linear low-density polyethylene, high-density polyethylene, polypropylene, ethylene-propylene copolymer, and mixtures thereof. The outer layer 12 may be composed of multiple layers. For example, the outer layer 12 may be composed of a recyclable layer sandwiched between layers made of virgin material. Here, the recyclable layer refers to a layer made of recycled flash produced during molding of a container. A specific example of the layer composition of the outer layer 11 is a three-layer composition of a polypropylene (PP) layer / recyclable layer / polypropylene (PP) layer. Furthermore, it is also possible to add a lubricant to the portion of the outer layer 11 that contacts the inner layer 12 to promote peeling between the outer layer 11 and the inner layer 12.

[0019] The inner layer 12 includes, for example, an EVOH layer provided on the outer surface side of the container, an inner surface layer provided on the inner surface side of the EVOH layer, and an adhesive layer provided between the EVOH layer and the inner surface layer. A specific example of the layer structure of the inner layer 12 is a three-layer structure of an EVOH layer / adhesive layer / polyethylene (PE) layer. By providing the EVOH layer, the gas barrier property and the peelability from the outer layer 11 can be improved.

[0020] The EVOH layer is a layer made of an ethylene-vinyl alcohol copolymer (EVOH) resin, and is obtained by hydrolysis of an ethylene and vinyl acetate copolymer. The ethylene content of the EVOH resin is, for example, 25 to 50 mol%, and is preferably 32 mol% or less from the viewpoint of oxygen barrier properties. The lower limit of the ethylene content is not particularly specified, but since the flexibility of the EVOH layer is more likely to decrease as the ethylene content decreases, it is preferably 25 mol% or more. In addition, the EVOH layer preferably contains an oxygen absorber. By containing an oxygen absorber in the EVOH layer, the oxygen barrier properties of the EVOH layer can be further improved.

[0021] The inner layer is the layer that comes into contact with the contents of the double container 1 and is made of a polyolefin such as low-density polyethylene, linear low-density polyethylene, high-density polyethylene, polypropylene, ethylene-propylene copolymer, and mixtures thereof, and is preferably made of low-density polyethylene or linear low-density polyethylene.

[0022] The adhesive layer is a layer that has the function of adhering the EVOH layer and the inner layer, and is, for example, a polyolefin to which an acid-modified polyolefin (e.g., maleic anhydride-modified polyethylene) in which a carboxyl group has been introduced is added, or an ethylene-vinyl acetate copolymer (EVA). One example of the adhesive layer is a mixture of low-density polyethylene or linear low-density polyethylene and acid-modified polyethylene.

[0023] Next, the cap 5 attached to the mouth 4 of the container body 2 will be described.

[0024] The cap 5 is a so-called plugging type cap, and in response to this, the mouth 4 of the container body 2 is configured with a plurality of steps with different outer diameters that are continuous along the axial direction. Specifically, the mouth 4 is provided with a large diameter mouth 4a that is located at the upper end and extends in the axial direction, a small diameter mouth 4b that is located below the large diameter mouth 4a and extends in the axial direction with an outer diameter smaller than that of the large diameter mouth 4a, and a maximum diameter mouth 4c that is located below the small diameter mouth 4b and extends in the axial direction with an outer diameter larger than that of the large diameter mouth 4a. A support mouth 4d is formed below the maximum diameter mouth 4c, which is smaller in diameter than the maximum diameter mouth 4c and larger in diameter than the large diameter mouth 4a. In addition, an annular recess 4e with approximately the same diameter as the small diameter mouth 4b is formed between the support mouth 4d and the storage section 3. This annular recess 4e is provided to be gripped by a plugging machine when the cap 5 is plugged into the mouth 4.

[0025] The cap 5 according to this embodiment squeezes the storage section 3 of the container body 2 to apply internal pressure to the container body 2, and immediately after using an appropriate amount of the contents, the check valve 51 seals the inside of the container body 2 without the user having to manually operate the cap 5. Specifically, as shown in FIG. 4, the cap 5 is composed of a cap body 5A having a discharge hole 52 for the contents, and a lid body 5B connected to a main cap body 53 constituting the cap body 5A via a hinge 5C. That is, the main components of the cap 5 are the main cap body 53 to which the lid body 5B is connected and which includes an annular wall portion, the check valve 51, and the inside plug 54 having the discharge hole 52. The lid body 5B may be configured as a separate body without being connected to the cap body 5A via the hinge 5C.

[0026] Check valve 51 has a valve portion that opens and closes discharge hole 52 by being seated on or off an annular valve seat around discharge hole 52, and is molded from, for example, a polyethylene elastomer. Inside plug 54 disposed above check valve 51 has discharge passage 55 that communicates with discharge hole 52 and discharges the contents from discharge hole 52 to the outside of the container. Main cap body 53 including lid body 5B is made of, for example, polypropylene, and inside plug 54 is made of, for example, polyethylene.

[0027] The double container 1, which is a peelable laminated container, needs to have an air inlet hole. The air inlet hole is a through hole provided only in the outer layer 11, and does not reach the inner layer 12. Air is introduced from this air inlet hole between the outer layer 11 and the inner layer 12, which are the outer shells, and only the inner layer 12 shrinks as the content is discharged. On the other hand, the outer layer 11 is restored to its original shape by its own restoring force when air is introduced from the air inlet hole.

[0028] Generally, a valve member (check valve) is provided in the air introduction hole to allow smooth discharge of the contents and restore the outer layer, but providing a valve member increases the number of parts, which causes an increase in manufacturing costs. Therefore, in the double container 1 of this embodiment, the valve member is omitted, and the installation position of the air introduction hole is optimized to achieve the same feeling of use as when a valve member is provided, even if the valve member is omitted, and it is possible to reduce the number of parts and suppress increases in manufacturing costs.

[0029] That is, the double container 1 of the present invention is characterized in its configuration in that it has an atmosphere introduction hole 20 without a valve formed in the outer layer 11, and is characterized in function in that the atmosphere introduction hole 20 is opened and closed by moving the inner layer 12 closer and farther apart. "Without a valve" means that the inner layer 12 has the valve function as described above, and no valve member formed as a separate member is provided.

[0030] The inventors have considered removing the valve member (check valve) in order to reduce the number of parts, but have found that the position of the air inlet hole for separating the outer layer and the inner layer of the double container makes a difference in the feeling of use. Furthermore, when discharging the contents, it is necessary to place the mouth part on the bottom, and they have found that the mouth part (especially the neck part, which is the base end part of the mouth part) is the best place for the outer layer and the inner layer to easily come into close contact at that time. Then, when an air inlet hole was opened at that location, a feeling of use comparable to that of a case with a valve was obtained. Generally, the mouth part and the neck part are circular, which has the advantage of being less likely to deform when discharging and less likely to leak air.

[0031] 5 is an enlarged view of the vicinity of the mouth 4 of the double container 1 of this embodiment. In this embodiment, an air introduction hole 20 is formed in the mouth 4 of the container body 2, particularly in the annular recess 4e formed in the vicinity of the base end of the mouth 4. As described above, the annular recess 4e is provided for gripping with a capping machine when capping the mouth 4 with the cap 5. The annular recess 4e has a smaller diameter than other parts, and is formed as an annular groove when viewed from the outside, and is formed by molding in a shape that protrudes toward the inside.

[0032] The annular recess 4e is a portion having a smaller diameter than the other portions, and is molded thicker than the other portions because the blow ratio is small during blow molding. The mouth and neck are circular and do not easily deform even during discharge, but the annular recess 4e is thicker, which makes it more resistant to deformation and further suppresses air leakage. In addition, the annular recess 4e is molded in a shape that protrudes inward, so that internal pressure is easily applied, and the inner layer 12 is reliably pressed against the outer layer 11, thereby reliably blocking the air introduction hole 20.

[0033] In this case, the opening diameter d of the air introduction hole 20 is preferably 1.0 mm to 1.5 mm. If the opening diameter d of the air introduction hole 20 exceeds 1.5 mm, the air introduction hole 20 may not be sufficiently blocked by the pressing of the inner layer 12, which may cause air leakage. Conversely, if the opening diameter d of the air introduction hole 20 is less than 1.0 mm, the introduction of air between the outer layer 11 and the inner layer 12 may be hindered.

[0034] The air introduction hole 20 is preferably formed at a position 180° opposite to the hinge 5C of the cap 5. When discharging the contents in the double container 1, the lid 5B connected by the hinge 5C is flipped up and the mouth 4 is squeezed downward. At this time, if the air introduction hole 20 is formed at a position 180° opposite to the hinge 5C of the cap 5, the air introduction hole 20 is located below the mouth 4, which makes it easier for the gravity of the contents to be applied, and the air introduction hole 20 is reliably closed.

[0035] Furthermore, in the double container 1 of this embodiment, the annular recess 4e formed in the mouth portion 4 is not covered by the cap 5, and therefore the atmosphere introduction hole 20 formed in the annular recess 4e is also not covered by the cap 5. Furthermore, in the double container 1 of this embodiment, the atmosphere introduction hole 20 is not provided with a valve member (check valve) as described above, and the path for introducing atmosphere into the atmosphere introduction hole 20 does not have a valve. For example, it is known to provide the atmosphere introduction hole in a position covered by a cap and provide a valve in the atmosphere introduction path of the cap, but even in such a case, no valve member is provided.

[0036] Fig. 6 shows a usage form of the double container 1 of this embodiment. In Fig. 6, the configuration of the cap 5 is illustrated in a simplified manner, and the check valve 51 and the like are omitted. The contents M filled in the double container 1 are, for example, mayonnaise, ketchup, soy sauce, ponzu sauce, olive oil, dressing, pork cutlet sauce, paste-like mustard, and the like.

[0037] To dispense the content M of the double container 1, as shown in Fig. 6(A), the double container 1 is tilted so that the mouth 4 is positioned downward, and the storage section 3 of the double container 1 is squeezed (pressed). At this time, the content M of the double container 1 falls from the storage section 3 toward the mouth 4, and the gravity is applied to the inner layer 12 near the mouth 4. The force of the squeeze is also applied as a force pressing against the content M, and as a result, the inner layer 12 is pressed from the inside and brought into close contact with the outer layer 11, sealing the air introduction hole 20.

[0038] When squeezed in this state, the air between the outer layer 11 and the inner layer 12 does not escape through the air inlet 20, and the squeezing force is applied to the contents M, causing the contents M to be discharged from the discharge passage 55 of the cap 5. The feeling of use is also good.

[0039] After dispensing, the double container 1 is placed in an upright position, and at this time, as shown in Fig. 6(B), the contents M fall toward the storage section 3, acting to peel the inner layer 12 from the outer layer 11. Therefore, the air introduction hole 20 provided in the outer layer 11 is opened, and air is quickly introduced between the outer layer 11 and the inner layer 12. As a result, the inner layer 12 remains in a contracted state, and the outer layer 11 is restored to its original shape.

[0040] As described above, in the double container 1 of this embodiment, even if a valve member (check valve) is not provided in the atmosphere inlet hole 20, it is possible to achieve a usability that is comparable to that in the case where a valve member is provided in the atmosphere inlet hole 20, simply by devising the position in which the atmosphere inlet hole 20 is formed.

[0041] Although an embodiment of the present invention has been described above, it goes without saying that the present invention is not limited to this embodiment, and various modifications are possible without departing from the spirit of the present invention. [Explanation of symbols]

[0042] 1 double container 2 Container body 3. Storage section 4 Mouth 4e Annular recess 5 Cap 11 Outer layer 12 Inner layer 20 Atmospheric Inlet Hole

Claims

1. A double container having an outer layer and an inner layer, the inner layer shrinking as the content contained in the inner layer decreases, A nozzle has a body and a mouth having an outer dimension smaller than that of the body and having a discharge port. an air inlet hole having no valve is formed in the outer layer at the mouth portion, A plug-type cap is attached to the mouth portion, and the air introduction hole is not covered by the cap, The double container is characterized in that the opening diameter d of the air introduction hole is 1.0 mm to 1.5 mm, and the air introduction hole is formed at a position 180° opposite to the hinge of the cap.

2. 2. The double container according to claim 1, wherein the mouth portion has an annular recess, and the air inlet hole is formed in the annular recess.

3. 3. The double container according to claim 2, wherein the annular recess is provided for gripping the cap with a capping machine when the cap is applied to the opening.

4. A double container having an outer layer and an inner layer, the inner layer shrinking as the content contained in the inner layer decreases, A nozzle has a body and a mouth having an outer dimension smaller than that of the body and having a discharge port. an air inlet hole having no valve is formed in the outer layer at the mouth portion, The mouth portion has an annular recess, and the air introduction hole is formed in the annular recess, A plug-type cap is attached to the mouth portion, The annular recess is provided for gripping the cap with a capping machine when the cap is capped on the opening, The double container is characterized in that the opening diameter d of the air introduction hole is 1.0 mm to 1.5 mm, and the air introduction hole is formed at a position 180° opposite to the hinge of the cap.

5. 5. The double container according to claim 1, wherein the opening comprises, in order from the top, a large diameter opening, a small diameter opening, a maximum diameter opening, a support opening, and an annular recess.

6. 6. The double container according to claim 1, wherein a path for introducing air into the air inlet has no valve.

Images