JP2021001023A - Double structure container - Google Patents

Abstract

To provide a double structure container manufactured by a stacking method, in which deformation of a fitting ring-shaped protrusion formed on a neck part of an inner bag container is effectively prevented.SOLUTION: In a double structure container composed of an outer cylinder container 3 and an inner bag container 5 stored inside the outer cylinder container 3, the outer cylinder container 3 has an outer cylinder neck part 11 and a body part 15 connected to the outer cylinder neck part 11 and formed by extending, the inner bag container 5 has an inner bag neck part 21 and a bag-like part 23 connected to the inner bag neck part 21 and formed by extending, on an outer surface of the inner bag neck part 21, a ring-like projection 43 for fitting and fixing with the inner surface of the outer cylinder neck part 11 is provided in a lower part, on an inner surface of the outer cylinder neck part 11 of the outer cylinder container 3, an air passage forming groove 37 for communicating a gap between the inner surface of the body part 15 of the outer cylinder container 3 and the outer surface of the bag-like part 23 of the inner bag container 5 with an outside extends in the axial direction.SELECTED DRAWING: Figure 2

Description

The present invention relates to a double-structured container including an outer cylinder container and an inner bag container inserted and held in the outer cylinder container, and more specifically, a double-structured container manufactured by a stacking method. Regarding the container.

Conventionally, a double-structured container having a double-structured structure consisting of an inner bag container and an outer cylinder container has been put into practical use as, for example, an airless bottle and a container for storing a seasoning liquid such as soy sauce. Such an airless bottle is used in combination with a cap with a check valve, and is filled in an inner bag container by squeezing and denting the body wall of the bottle, which is an outer cylinder container, from the outside. When the content liquid is discharged from the pouring path formed in the cap and the discharge of the content liquid is completed by stopping the pressing of the body wall of the bottle, the air is sent to the inner bag container by the action of the check valve. It will not be introduced, but will be introduced into the space between the inner bag container and the outer cylinder container through a flow path different from the pouring path of the cap. As a result, the inner bag container shrinks by the amount that the content liquid is discharged, and each time the content liquid is discharged, the inner bag container shrinks. In an airless bottle in which the content liquid is discharged by such a method, the content liquid can be dispensed and the intrusion of air into the inner bag container filled with the content liquid is effectively prevented. There is an advantage that the freshness of the content liquid can be maintained for a long period of time.

In order to ensure the flow of air as described above, an introduction port that penetrates the wall of the neck of the outer cylinder container is generally provided, and further, a tubular side wall of a cap attached to the neck of the outer cylinder container ( A valve body that swings up and down is provided on the inner surface of the skirt portion), and the valve body is configured to control the flow of air through the introduction port (see, for example, Patent Document 1). ..
Therefore, in the double-structured container as described above, it is necessary to form an air inlet by post-processing, and there is a problem that the productivity is low.

Further, the cap attached to the double-structured container is generally attached by screw engagement (for example, Patent Document 2), but in such a method, the neck portion of the outer cylinder container (or the neck portion of the inner cylinder container). A screw thread for attaching the cap is required on the outer surface of the container, which increases the height of the outer cylinder container and the inner bag container, resulting in a large amount of resin and a heavy container weight. It ends up.

Therefore, there is a double-structured container that allows air to be taken in and out of the space between the outer cylinder container and the inner bag container in an extremely simple form without forming an air inlet at the neck of the outer cylinder container. Further, there is also a demand for a double-structured container having a form suitable for attaching a cap by plugging and fitting.

As a double-structured container that satisfies the above requirements, the Applicant first
In a double-structured container consisting of an outer cylinder container and an inner bag container housed inside the outer cylinder container,
The outer cylinder container has an outer cylinder neck portion and a body portion connected to the outer cylinder neck portion and formed by stretching.
The inner bag container has an inner bag neck portion and a bag-shaped portion connected to the inner bag neck portion and formed by stretching.
The outer surface of the inner bag neck portion is provided with a ring-shaped protrusion for fitting and fixing to the inner surface of the outer cylinder neck portion at a lower portion, and the ring-shaped protrusion has a notch for forming an air passage. At the same time, a small flange having a diameter smaller than that of the ring-shaped protrusion extends outward in the horizontal direction at the upper end of the inner bag neck portion.
A double-structured container characterized in that, in a state where the inner bag container is housed in the outer cylinder container, the ring-shaped protrusion of the inner bag neck portion is fitted and fixed to the inner surface of the outer cylinder neck portion.
(Japanese Patent Application No. 2019-54865). That is, in this double-structured container, a stack preform is obtained by fitting and fixing the preform for the inner bag container to the preform for the outer cylinder container, and this stack preform is arranged in the blow mold to form the inner bag. Manufactured by blow molding by supplying blow fluid into a container preform.

The above-mentioned double-structured container proposed by the applicant has an extremely simple form without forming an air inlet at the neck of the outer cylinder container (working space) between the outer cylinder container and the inner bag container. It is possible to take air in and out of the container.

As a result of further study on the structure of the double-structured container as described above, the present inventors further studied the space between the outer cylinder container and the inner bag container in an extremely simple form even in a form different from the above. We obtained the knowledge that it is possible to move air in and out of (working space).

JP-A-2018-2198 JP-A-2017-222141

Therefore, an object of the present invention is a double-structured container manufactured by the stack method, in which air is taken in and out of the space (working space) between the outer cylinder container and the inner bag container in an extremely simple form. The purpose is to provide a double-structured container that can be used.

According to the present invention, in a double-structured container composed of an outer cylinder container and an inner bag container housed inside the outer cylinder container,
The outer cylinder container has an outer cylinder neck portion and a body portion connected to the outer cylinder neck portion and formed by stretching.
The inner bag container has an inner bag neck portion and a bag-shaped portion connected to the inner bag neck portion and formed by stretching.
On the outer surface of the inner bag neck portion, a ring-shaped protrusion for fitting and fixing with the inner surface of the outer cylinder neck portion is provided in a lower portion.
On the inner surface of the outer cylinder neck portion of the outer cylinder container, an air passage forming groove for communicating the gap between the inner surface of the body portion of the outer cylinder container and the outer surface of the bag-shaped portion of the inner bag container with the outside is axially oriented. A double-structured container characterized by extending into is provided.

In the double-structured container of the present invention, the following aspects are preferably adopted.
(1) A stepped surface that regulates the descent of the ring-shaped protrusion is formed on the inner surface of the outer cylinder neck portion, and the air passage forming groove is formed so as to at least straddle the stepped surface. ..
(2) The inner surface of the outer cylinder neck portion is formed with an inclined surface that is continuous with the upper end surface and has a reduced diameter as it goes downward, and the air passage forming groove extends at least until it straddles the stepped surface. , Extending downward from the lower end of the inclined surface.
(3) The inclined surface is an engaging surface with an air valve provided on the cap, and the inclined surface is formed with a recess for pressure adjustment.
(4) The recess has a shape in which the upper part is wide.
(5) The inclined surface is an engaging surface with an air valve provided on the cap, and the inclined surface is formed with a convex portion for pressure adjustment.

The double-structured container of the present invention comprises an outer cylinder container and an inner bag container housed inside the outer cylinder container, and the neck portion (inner bag neck portion) of the inner bag container housed in the outer cylinder container. ) Is provided on the outer surface of the outer cylinder container with a ring-shaped protrusion for fitting and fixing with the inner surface of the neck portion (outer cylinder neck portion) of the outer cylinder container, as can be understood from the structure, which is manufactured by the stack method. In the double-structured container having such a structure, in the present invention, an air passage forming groove extending in the axial direction is provided on the inner surface of the neck portion of the outer cylinder container, whereby the inner surface of the body portion of the outer cylinder container is provided. The gap (working space) between the inner bag container and the outer surface of the bag-shaped portion of the inner bag container is communicated with the outside, and air is discharged from the working space and introduced into the working space.

In the present invention, since the ring-shaped protrusion is not formed and the air passage is secured by the air passage forming groove formed on the inner surface of the outer cylinder neck portion, the ring-shaped protrusion has high strength and is inner. The neck of the bag container can be firmly fitted and fixed inside the neck of the outer cylinder.

The schematic diagram for demonstrating the basic function of a double-structured container. A side sectional view showing a suitable neck shape together with a part of a cap in the double-structured container of the present invention. FIG. 2 is a schematic perspective view of an outer cylinder neck portion in the double-structured container of FIG. The schematic perspective view of the inner bag neck part in the double-structured container of FIG. The perspective view which shows the part of the neck part in the state which the inner bag container is fitted and fixed in the outer cylinder container in the double structure container of this invention. The figure which shows the outer cylinder preform used for molding of the double structure container of this invention. The figure which shows the inner bag preform used for molding of the double structure container of this invention. The figure which shows the stack preform formed from the outer cylinder preform of FIG. 6 and the inner bag preform of FIG. In the inner bag preform shown in FIG. 7, a cross-sectional view taken along the QQ plane in FIG. 7 (c). The figure which shows the neck part in the state which the cap is attached to the double structure container of this invention. Schematic perspective view of a modified example of the outer cylinder neck. FIG. 11 is a cross-sectional view taken along the line LL of the outer cylinder neck portion shown in FIG.

First, the basic functions of the double-structured container will be briefly explained.
With reference to the schematic view of FIG. 1, the double-structured container shown by 1 as a whole is composed of a bottle-shaped outer cylinder container 3 and an inner bag container 5 in which a content liquid such as soy sauce is stored. As is understood, the inner bag container 5 is inserted and held inside the outer cylinder container 3.

The outer cylinder container 3 has a neck portion (outer cylinder neck portion) 11, a shoulder portion 13 connected to the outer cylinder neck portion 11 and expanding in diameter downward, and a body portion 15 connected to the shoulder portion 13. The lower end of the body portion 15 is closed by the bottom portion 17. A support ring 19 is formed on the outer surface of such an outer cylinder neck portion 11, and a cap is fitted and fixed to a portion above the support ring 19.
Further, the inner bag container 5 is composed of a neck portion (inner bag neck portion) 21 and a bag-shaped portion 23 in a bulging form connected to the inner bag neck portion 21.

The outer cylinder container 3 and the inner bag container 5 as described above are not limited to this, but are blow-moldable thermoplastics typified by, for example, polyester such as polyethylene terephthalate and polyolefin such as polyethylene and polypropylene. It is molded using resin.

In the double-structured container 1 as described above, the body portion 15 of the outer cylinder container 11 usually has a slightly recessed shape, and by pressing (squeezing) the recessed portion (squeeze region), the body portion 15 has a slightly recessed shape. The body portion 15 is greatly dented, and the bag-shaped portion 23 of the inner bag container 5 is pressed accordingly, whereby the content liquid contained in the bag-shaped portion 23 is discharged. When the content liquid is discharged, the bag-shaped portion 23 contracts according to the weight loss of the content liquid, but the body portion 15 of the outer cylinder container 3 returns to its original shape due to its elasticity, and a gap (working space) between the two is restored. Z) will be formed.

By the way, when the discharge operation as described above is repeated, the bag-shaped portion 23 contracts more greatly according to the amount of the content liquid discharged. Therefore, when the air in the working space Z described above is discharged when the body portion 15 is squeezed, the body portion 15 of the outer cylinder container 3 is used in order to discharge the content liquid in the contracted bag-shaped portion 23. It must be pressed harder and deformed significantly, and eventually the contents cannot be discharged. Therefore, when the body portion 15 is pressed to discharge the content liquid, the air in the working space Z is not discharged, the air is allowed to exist in the working space Z, and the bag-shaped portion 23 is pressed through the air layer. It is necessary to
Further, when the content liquid is discharged, the volume of the bag-shaped portion 23 is reduced by the amount of the content liquid discharged, while the body portion 15 of the outer cylinder container 3 recovers from the recessed state, so that the inside of the working space Z Is in a negative pressure state. Therefore, after the content liquid is discharged, it is necessary to introduce air into the working space Z and return the pressure in the working space Z to normal pressure. If the negative pressure remains, not only does the body 15 not return to its original shape smoothly, but then when the body 15 is pressed to discharge the content liquid, the body 15 must be greatly recessed. This is because it becomes difficult to effectively discharge the content liquid.

Therefore, it is required that the discharge of air from the working space Z is prevented, and that air is appropriately introduced into the working space Z. That is, it is necessary to form an air passage for taking air in and out of the working space Z.

In the double-structured container 1 having the above structure, the preform for forming the inner bag (inner bag preform) is inserted and held inside the preform for forming the outer cylinder (outer cylinder preform). It is manufactured by stretch blow molding using the stack preform, and in the outer cylinder container 3, the shoulder portion 13, the body portion 15 and the bottom portion 17 are portions thinned by blow stretching, and the inner bag is formed. In the container 5, the bag-shaped portion 23 is a portion thinned by blow stretching. That is, in such a double-structured container, the outer cylinder neck portion 11 and the inner bag neck portion 21 are non-stretched portions that are not blow-molded, and have the same shape as before molding, and the inner bag neck portion 21 has the same shape as before molding. , It is fitted and fixed in the outer cylinder neck portion 11. Further, in the state immediately after blow molding, the bag-shaped portion 23 of the inner bag container 5 is in close contact with the shoulder portion 13, the body portion 15 and the bottom portion 17 of the outer cylinder container 3, and the above-mentioned working space Z is closed. It is in a state of being

With reference to FIG. 1 described above and with reference to FIGS. 2 to 5 showing the structure of the double-structured container of the present invention, the outer surface of the upper end portion of the neck portion (outer cylinder neck portion) 11 of the outer cylinder container 3 is undercut. 31 is formed, and the cap 100 is attached by utilizing the engagement with the undercut 31, and is stably held. Further, the undercut 31 is partially cut out so that an air passage X (see FIG. 2) from the working space Z to the outside is formed along the inner surface, the upper end surface, and the outer surface of the outer cylinder neck portion 11. An air passage forming slit 31a is formed. As can be seen from FIG. 3, the slit 31a has a bifurcated inverted V shape so that air can easily flow. The number and shape of such slits 31a are not particularly limited, but if they are provided at a plurality of locations within a range that does not impair the engaging force with the cap 100, air can be smoothly taken in and out of the working space Z. Is suitable.

An inclined surface 33 inclined inward is formed at the upper end of the inner surface of the outer cylinder neck portion 11. The inclined surface 33 is an engaging surface (contact surface) with the air valve A of the cap 100 described below, and air into the working space Z is utilized by utilizing the contact and disengagement of the air valve A. In addition, it is possible to secure a valve function of blocking the discharge of air from the working space Z. Further, as shown in FIG. 3, the inclined surface 33 is provided with a pressure adjusting recess 34, and the pressure adjusting recess 34 reinforces the function of the air valve A of the cap 100. It is supposed to be done. The function of such a pressure adjusting recess 34 will be described later.

Further, on the inner surface of the outer cylinder neck portion 11, the portion below the inclined surface 33 is a straight straight body surface D, and as shown in FIGS. 2 and 3, the lower end of the straight body surface D. In addition, a stepped surface 35 projecting inward is formed. The stepped surface 35 is formed to stabilize the position of the inner bag neck portion 21 in the outer cylinder neck portion 11.

Further, on the straight body surface D of the inner surface of the outer cylinder neck portion 11, an air passage is formed which extends linearly in the axial direction from the lower end portion of the inclined surface 33 so as to straddle the stepped surface 35. It is important that the groove 37 is formed. As shown in FIG. 3, a large number of such grooves 37 are formed at regular intervals, and by providing such grooves 37, the above-mentioned air passage X can be secured. Further, since a large number of air passage forming grooves 37 extend straight at positions above the stepped surface 35 at intervals in the circumferential direction, the inner bag neck portion 21 is inserted into the outer cylinder neck portion 11 and fitted. At the time of fixing, these grooves 37 function as guides, and the inconvenience that the inner bag neck portion 21 is diagonally inserted and fitted and fixed can be effectively prevented.
Although the straight body surface D is shown as a straight body shape, it is actually a slightly inclined tapered surface for die cutting at the time of molding.

On the other hand, as shown in FIGS. 2 and 4, the upper end of the outer surface of the neck portion (inner bag neck portion 21) of the inner bag container 5 located inside the outer cylinder neck portion 11 protrudes outward. A small flange 41 is formed. The small flange 41 is formed to be gripped by a predetermined jig when the preform for the inner bag is inserted into the preform for the outer cylinder at the stage before blow molding. .. Further, the small flange 41 is formed with recesses 41a at a plurality of locations. That is, by forming such a recess 41a, the holder for assembling the stack preform by fitting and fixing the inner bag preform described later to the outer cylinder preform can be easily attached and detached. Because it can be done. For example, if a notch corresponding to the recess 41a is provided, the neck portion of the inner bag preform is inserted into the holder, and the holder is rotated 90 degrees, the inner bag preform is placed in the holder. It is held stably, and the stack preform can be held stably by transporting it, fitting and fixing it in the outer cylinder preform by tapping, etc. Furthermore, blow molding can also be performed, and after the operation is completed, By rotating the holder 90 degrees, the holder can be quickly removed.

Further, on the outer surface of the inner bag neck portion 21, a ring-shaped protrusion 43 for fitting and fixing is provided below the small flange 41. That is, the ring-shaped protrusion 43 has a disk shape, and its outer diameter is comparable to the inner diameter of the outer cylinder neck portion 11, and when the inner bag neck portion 21 is inserted into the outer cylinder neck portion 11, the ring shape is formed. The outer surface of the protrusion 43 is in close contact with the inner surface of the outer cylinder neck portion 11, and is firmly and stably fitted and held without rattling. Further, at this time, the ring-shaped protrusion 43 engages with the stepped surface 35 formed on the outer cylinder neck portion 11, so that the inner bag neck portion 21 is positioned so as not to be deeply inserted.
That is, the ring-shaped protrusion 43 is not formed with a notch for securing the air passage X, and the above-mentioned air passage forming groove 37 extends in the axial direction so as to straddle the stepped surface 35. Therefore, the air passage X is secured by the air passage forming groove 37. Therefore, the ring-shaped protrusion 43 is completely circular, so that the strength decrease due to the formation of the notch is avoided, and the inner bag neck portion 21 can be firmly fixed in the outer cylinder neck portion 11 with a large fitting force. ..

The lower portion of the ring-shaped protrusion 43 has a smaller diameter than the upper portion, and as a result, a step portion 43a is formed on the ring-shaped protrusion 43. That is, the stepped portion 43a meshes with the stepped surface 35 formed on the inner surface of the outer cylinder neck portion 11, whereby the inner bag neck portion 21 is firmly held.
Further, in order to prevent the ring-shaped protrusion 43 that meshes with the stepped surface 35 from being displaced upward, the straight body surface D on the inner surface of the outer cylinder neck portion 11 is provided as long as the die-cutting property at the time of molding is not impaired. Small protrusions can also be provided.

Further, the small flange 41 described above is formed to have a smaller diameter than the ring-shaped protrusion 43. Therefore, in a state where the inner bag neck portion 21 is fitted and fixed in the outer cylinder neck portion 11, the small flange 41 at the upper end of the inner bag neck portion 11 does not cover the upper end surface of the outer cylinder neck portion 11, and the ring-shaped protrusion 43 A straight space Y is directly communicated with the upper space along the inner surface of the outer cylinder neck portion 11 (see FIG. 2). Moreover, an air passage forming groove 37 is formed on the inner surface of the outer cylinder neck portion 11 so as to straddle the stepped surface 35, so that the above-mentioned working space Z and the above-mentioned straight space Y communicate with each other. Has been done. Therefore, it is possible to form an air passage X from the working space Z to the outside through this straight space Y.

Further, in the inner bag neck portion 21 of the above-described form, it is preferable that the region 45 between the small flange 41 and the ring-shaped protrusion 43 has a polyhedral shape. By forming the region 45 into a polyhedral shape, the strength of the inner bag neck portion 21 can be increased, which is advantageous in that blow molding in the state of stack preform, which will be described later, is stably performed. Further, if this region 45 is formed in a circular shape, the space Y may become narrow and the air flow along the air passage X may become unstable when expanded by heating for blow molding. However, by forming the polyhedron shape as described above, the space Y can be maintained at a constant size even if thermal expansion occurs, and the air flow along the air passage X is stably secured. It also has the advantage of being able to.

As shown in FIG. 2, the double-structured container 1 of the present invention having the above-mentioned structure is put into use with the cap shown by 100 as a whole.
Although the schematic structure of the cap 100 is shown in FIG. 2, the contents contained in the inner bag container 5 are allowed to be discharged, but the reverse is prevented from flowing into the inner bag container 5. The check valve is omitted, and the upper lid provided on the cap 100 is also omitted. Explaining with reference to FIG. 10 together with FIG. 2, the cap 100 is attached to the neck portion 11 of the outer cylinder container 3, and an air valve A is provided in addition to the omitted check valve. On the outer surface of the tubular side wall 121 of the cap 100, a circumferential protrusion B that engages with the undercut 31 formed on the outer cylinder neck portion 11 described above is formed, and is connected to the tubular side wall 121. The top plate portion 125 extending in the horizontal direction is provided with an inner ring C extending downward at a distance from the tubular side wall 121. As can be understood from FIG. 2, the air valve A is an annular flap piece extending downward in the cap axial direction, is swingable to the left and right, and has the tubular side wall 121 and the inner ring C. At a position between and, it extends downward from the top plate portion 125, and its lower end is in contact with an inclined surface 33 formed at the upper end of the inner surface of the outer cylinder neck portion 11.

In such a cap 100, the outer surface of the inner ring C is in close contact with the inner surface of the neck portion 21 of the inner bag container 5, whereby the sealing property of the inner bag container 5 is ensured. Further, although not shown, the peripheral projection B formed on the inner surface of the tubular side wall 121 has a notch formed in a part thereof, and an air passage X formed from the working space Z to the outside is formed. It is configured so that it will not be blocked.

When the cap 100 is attached to the double-structured container 1 (neck 11 of the outer cylinder container 3), the outer cylinder container is placed in the space between the air valve A (flap piece) and the tubular side wall 121 of the cap 100. The upper end portion of the neck portion 11 of 3 is in a state of being inserted. That is, as described above, the small flange 41 does not cover the upper end surface of the outer cylinder neck portion 11, and a straight space Y is formed on the upper portion of the ring-shaped protrusion 43 along the inner surface of the outer cylinder neck portion 11. Therefore, such an air valve A can be in a state of being inserted. With such a structure, it is not necessary to form an introduction port for securing the air passage X in the outer cylinder neck portion 11, and the double-structured container 1 can be manufactured without post-processing.

That is, the neck portion 21 of the inner bag container 5 is located on the inner surface side of the air valve A, and when the air valve A swings and tilts outward, the lower end of the air valve A is the outer cylinder. It comes into contact with the inner surface (inclined surface 33) of the neck portion 11 of the container 3.

In the double-structured container 1 to which the cap 100 as described above is attached, under normal conditions, the air passage X communicating the working space Z and the outside is blocked by the contact between the air valve A and the inclined surface 33. Has been done. That is, the air passage X passing through the air passage forming groove 37 is closed by the air valve A. In this state, when the upper lid of the cap 100 is opened, the double-structured container 1 is tilted, and the body portion 15 (squeeze region in FIG. 1) of the outer cylinder container 3 is squeezed and recessed, the bag-shaped portion of the inner bag container 5 is recessed. 23 is also recessed, whereby the content liquid in the inner bag container 5 is discharged to the outside through a check valve (omitted in FIG. 2) formed in the cap 100. At this time, the pressure in the working space Z rises due to the dent of the body portion 15, but the air valve A bends outward due to this pressure rise and is strongly pressed against the inclined surface 33, so that the air passage X is opened. Therefore, the air in the working space Z does not flow to the outside. Even if the air valve A and the inclined surface 33 are separated from each other in the normal state, the internal pressure in the working space Z rises sharply when squeeze, so that the air valve A flexes greatly outward. Since it comes into contact with the inclined surface 33, the air passage X passing through the air passage forming groove 37 remains closed, and the air in the working space Z does not flow to the outside during the squeeze.

On the other hand, when the squeeze of the body portion 15 is stopped, the check valve provided on the cap 100 is closed, and air does not flow into the inner bag container 5 from the outside, but the outer cylinder container 3 recessed by the squeeze. The body portion 15 returns to its original shape. Therefore, the bag-shaped portion 23 of the inner bag container 5 shrinks by the amount that the content liquid is discharged, but the working space Z becomes a negative pressure due to the restoration of the body portion 15 of the outer cylinder container 3 to its original shape. As a result, the air valve A that was in contact with the inclined surface 33 bends inward, a gap is formed between the air valve A and the inclined surface 33, and the air passage X passing through the air passage forming groove 37 is opened. Air will flow into the working space Z from the outside. Therefore, when the body portion 15 of the outer cylinder container 3 is squeezed next time, air exists in the working space Z, and air is present between the bag-shaped portion 23 of the inner bag container 5 and the body portion 15 of the outer cylinder container 3. The layer is present, and the bag-shaped portion 23 that has shrunk due to the previous discharge of the content liquid is quickly pressed, and the content liquid is quickly discharged as in the previous squeeze.
For example, when air does not flow into the working space Z after the squeeze is stopped, the bag-shaped portion 23 is contracted, so that it is necessary to strongly press the body portion 15 to make a large dent in order to discharge the content liquid. Eventually, the contents liquid cannot be discharged. In the double-structured container 1 of the present invention, such an inconvenience is effectively solved by forming an inclined surface 33 in contact with the air valve A.

In the above description, an example is shown in which the air valve contact surface with which the air valve A contacts is an inclined surface 33, but instead of such an inclined surface, a normal straight straight body surface is used as the air valve. It can also be used as a contact surface. That is, the air valve A made of the annular flap piece bends outward during squeezing and comes into contact with the inner surface of the outer cylinder neck portion 11. Therefore, if the upper end of the air passage forming groove 37 is located below the portion in contact with the air valve A, the discharge of air can be effectively prevented.
However, when the air valve contact surface is a straight body surface, the air valve A is likely to be deformed when the cap 100 is attached by the stopper. Therefore, from the viewpoint of attaching the cap 100 by the stopper. The air valve contact surface is preferably an inclined surface 33 as described above.
Further, in the example of FIG. 2, the air valve A has a structure in contact with the outer cylinder neck portion 11, but depending on the form of the cap, such a structure is not adopted, for example, the wall of the cap located on the space Y. It is also possible to adopt a structure in which an opening is provided in the portion and the opening is opened and closed by an air valve A that swings up and down.

Further, in the above aspect, as shown in FIG. 3, it is preferable that the inclined surface 33 is provided with the pressure adjusting recesses 34 at a plurality of places. That is, by forming the pressure adjusting recess 34 in this way, it is possible to effectively degas when the pressure in the working space Z rises due to a change in the environmental temperature (temperature rise). For example, if the air valve contact surface is a straight upright surface, when the internal pressure rises due to such a temperature rise, the air valve A contacts the upright surface, so that gas is not vented from the working space Z. .. Therefore, when the upper lid of the cap 100 is opened, the content liquid may be discharged. However, when the air valve contact surface is an inclined surface 33 and the above-mentioned pressure adjusting recess 34 is formed, when the air valve A is slightly bent outward due to an increase in internal pressure to the extent of a change in environmental temperature, this The air valve A is located on the pressure adjusting recess 34, and a gap is formed between the air valve A and the inclined surface 33. Therefore, degassing is performed through the gap portion, which can prevent the content liquid from being discharged when the upper lid of the cap 100 is opened. Of course, at the time of squeeze, the internal pressure of the working space Z rises significantly and the air valve A bends outward significantly, so that air is not discharged through the pressure adjusting recess 34.

As described above, the pressure adjusting recess 34 formed on the inclined surface 33 has a pressure adjusting function by venting gas, and reinforces the function of the air valve A. Since such a pressure adjusting recess 34 is provided for discharging air to the outside and is not formed for introducing air into the inside, it is shown in a partially enlarged view in FIG. As shown, it is preferable that the upper side has a wide shape and the lower side has a narrow shape, and with such a shape, degassing can be smoothly performed. Further, in order to ensure that the air passage X is shut off by the air valve A, it is preferable that the pressure adjusting recess 34 exists at a position deviated from the extension line of the air passage forming groove 37.

In the present invention, the above-mentioned degassing function can also be exerted by forming a groove (gas venting groove) on the outer surface (the surface on the side in contact with the inclined surface 33) of the air valve A. .. Therefore, instead of the pressure adjusting recess 34 as described above, a degassing groove can be formed in the air valve A, and at the same time as providing the degassing groove, the pressure adjusting recess 34 is provided. You can also.

The double-structured container 1 of the present invention having the above-mentioned structure is manufactured by the so-called stack preform method, as described briefly above.
An example of such a preform form is shown in FIGS. 6-9.

6A and 6B are views showing a preform (outer cylinder preform) for forming the outer cylinder container 3, where FIG. 6A is a perspective view, FIG. 6B is a side view, and FIG. 6C is a side sectional view. ..
In FIG. 6, this outer cylinder preform is shown by 51, has a test tube shape as a whole, and the upper portion is the outer cylinder neck portion 11 of the above-mentioned form, and the outer cylinder neck portion 11 The continuous tubular portion 53 is a stretch-molded portion.

That is, as described above, the outer cylinder neck portion 11 of the outer cylinder preform 51 is formed with a support ring 19 and an undercut 31 on the outer surface thereof, and the undercut 31 is used to secure an air passage X. A notch 31a is formed. Further, an inclined surface 33 is formed at the upper end on the inner surface of the outer cylinder neck portion 11, a pressure adjusting recess 34 is formed on the inclined surface 33, and a stepped surface 35 is further below the inclined surface 33. It is formed. Further, from the lower end of the inclined surface 33, a plurality of air passage forming grooves 37 extending in the axial direction are formed at regular intervals in the circumferential direction so as to straddle the stepped surface 35. Since the outer cylinder neck portion 11 is a non-stretch molded portion that is not blow-stretched, the form of such an outer cylinder neck portion 11 is basically the same before and after blow molding.

Further, the tubular portion 53, which is the stretch-molded portion, is blow-molded to form the shoulder portion 13, the body portion 15, and the bottom portion 17 of the outer cylinder container 3 described above.

7A and 7B are views showing an inner bag preform 61 for forming the inner bag container 5, where FIG. 7A is a perspective view, FIG. 7B is a plan view, FIG. 7C is an AOA side sectional view, and FIG. Is a bottom view.
The inner bag preform 61 also has a test tube shape as a whole, the upper part is the inner bag neck portion 21 of the above-mentioned form, and the tubular portion 63 connected to the inner bag neck portion 21 is stretch-molded. It is a department.

That is, as described above, the inner bag neck portion 21 of the inner bag preform 61 is provided with a small flange 41 at the upper end and a ring-shaped protrusion 43 below the small flange 41 on the outer surface thereof. Further, as described above, the small flange 41 is formed with a notch 41a, and the region 45 between the small flange 41 and the ring-shaped protrusion 43 has a polyhedral shape (that is, its plane surface). The shape is polygonal).
Since such an inner bag neck portion 21 is a non-stretched molded portion that is not blow-stretched, the shape of the inner bag neck portion 21 is basically the same before and after blow molding.

Further, as can be understood from the side sectional view of FIG. 7C, the tubular portion 63, which is a stretch-molded portion, has a tapered portion whose upper portion is inclined inward and whose diameter becomes smaller toward the lower side. It is 63a, and the portion below the lower end of the tapered portion 63a is the straight body portion 63b. With such a form, the inner bag preform 61 can be easily inserted into the outer cylinder preform 51. Further, when the tubular portion 63 of the inner bag preform 61 having such a form is blow-molded, the circumferential stretching ratio of the tapered portion 63a is small and the circumferential stretching ratio of the straight body portion 63b is large. Therefore, in the bag-shaped portion 23 of the inner bag container 5, the portion corresponding to the shoulder portion 13 of the outer cylinder container 3 is relatively thick, while the portion corresponding to the body portion 15 is thin. Therefore, when the bag-shaped portion 23 contracts with the discharge of the contents, the contracted form contracts from the portion corresponding to the lower body portion 15 while maintaining the shape of the portion corresponding to the upper shoulder portion 13. It is regulated to go. As a result, it is possible to suppress the inconvenience that the contents are difficult to be discharged due to the shrinkage of the bag-shaped portion 23.

The inner bag preform 61 and the outer cylinder preform 51 as described above are both molded by injection molding using the above-mentioned thermoplastic resin suitable for blow molding (for example, a polyester resin such as polyethylene terephthalate). The inner bag preform 61 is inserted into the outer cylinder preform 51 to assemble the stack preform 71 shown in FIG.
In the stack preform 71, the portion where the inner bag neck portion 21 is inserted into the outer cylinder neck portion 11 is the non-stretched region α, and the portion below this region α is the stretched region β. That is, in this stack preform 71, the form of the non-stretched region α is the form shown in FIGS. 2 and 5 described above.

The stack preform 71 having the above-described form is heated to a predetermined draw molding temperature and placed in a blow molding mold, and a blow fluid such as compressed air is blown into the stack preform 71 (inner bag preform 61). As a result, blow molding is performed. That is, the tubular portion 63 of the inner bag preform 61 is stretched while expanding the tubular portion 53 of the outer cylinder preform 51 by expansion, and as a result, the tubular portion 53 of the outer cylinder preform 51 is formed into a molded mold. Correspondingly, it is shaped into the form of the shoulder portion 13, the body portion 15, and the bottom portion 17. On the other hand, the tubular portion 63 of the inner bag preform 61 is shaped into the form of a bag-shaped portion 23 that is in close contact with the inner surfaces of the shoulder portion 13, the body portion 15, and the bottom portion 17 of the outer cylinder container 3, and thus the second of the present invention. The heavy-duty container 1 is manufactured.

In the stack preform 71 shown in FIG. 9, the inner bag preform 61 is completely inserted into the outer cylinder preform 51, and the upper end of the outer cylinder preform 51 and the upper end of the inner bag preform 61 Although assembled so as to be located on the same surface, the present invention is not limited to this form, and for example, the upper end of the inner bag preform 61 (that is, the small flange 41 at the upper end of the inner bag neck 21) is , The form may be such that it exists in a state of protruding from the upper end of the outer cylinder preform 51 (that is, the upper end of the outer bag neck portion 11).
In this case, blow molding is performed with the jig inserted in the space between the small flange 41 at the upper end of the inner bag preform 61 and the upper end of the outer cylinder neck portion 11, and after blow molding, the jig is pulled out. By pushing the upper end of the protruding inner bag neck portion 21 into the outer cylinder neck portion 11 (plugging), the form shown in FIGS. 2 and 5 can be obtained. When the stack preform 71 is formed in such a form, a gap can be formed between the bag-shaped portion 23 of the inner bag container 5 and the shoulder portion 13 of the outer cylinder container 3 after molding. When discharging the content liquid, there is an advantage that air can be quickly introduced into the working space Z.

Returning to FIG. 7, in the present invention, the inner bag preform 61 is a region of the lower portion of the ring protrusion 43 as shown in FIGS. 7 (a) and 7 (d). That is, it is preferable that the outer surface of the tapered portion 63a has a polyhedral shape. More specifically, on the outer surface of the tapered portion 63a, a polyhedral base 81 having a polygonal planar shape is formed at the upper end portion in contact with the lower surface of the ring-shaped protrusion 43, and ribs are formed from the lower side of the polyhedral base 81. 83 extends downward.
With reference to the plan sectional view of FIG. 8 showing the shape of the rib 83, a plurality of ribs 83 (12 in the example of the figure) are formed, and each has a substantially triangular cross section, and the apex thereof. Is connected to each corner portion 81a of the polyhedron base portion 81, and forms a ridge line 83a extending downward from the corner portion 81a. Such a rib 83 has a form in which the height and width of the triangular cross section (the length of the base of the triangular shape) gradually decrease as it goes downward.

That is, by making the outer surface shape of the tapered portion 63a a polyhedron as described above, when this is blow-molded, the portion of the bag-shaped portion 23 to be molded that faces the shoulder portion 13 of the outer cylinder container 3 or its vicinity thereof. A wall thickness distribution can be formed in. For example, the portion of the polyhedral shape corresponding to the corner portion 81a and the ridge line 83a is formed to be thick, and the portion between the corner portion 81a and the ridge line 83a is thin. By forming such a wall thickness distribution, in the obtained double-structured container 1, the detachability of the bag-shaped portion 23 of the inner bag container 5 at the shoulder portion 13 of the outer cylinder container 3 is further improved and acts. It is extremely suitable for securing an air passage X connected to the space Z. That is, at the stage immediately after blow molding, as described above, the bag-shaped portion 23 of the inner bag container 5 is in close contact with the shoulder portion 13, the body portion 15, and the bottom portion 17 of the outer cylinder container 3. , The detachability in or near the shoulder portion 13 as described above is extremely important.

The polyhedral shape is not limited to the above-mentioned form as long as the wall thickness distribution is formed by blow molding. For example, the polyhedron shape is formed only by the polyhedral base 83 without forming the rib 83. Alternatively, the cross-sectional shape of the rib 83 may be a polygonal shape other than a triangular shape. Further, the number of faces of the polyhedron is not particularly limited and varies depending on the size of the target container, but in general, the polyhedron base 81 is 8 to 24 faces. Suitable. Further, although the ridge line 83a of the rib 83 extends downward from each of the corner portions 81a of the polyhedron base portion 81, the rib 83 can be formed so that the ridge line 83a extends from a part of the corner portion 81a. However, from the viewpoint of separation from the shoulder portion 13 of the bag-shaped portion 23 or its vicinity, it is preferable that the rib 83 is formed so that the ridge line 83a extends from all the corner portions 81a.
Further, in blow molding, it is desirable that the polyhedron base 81 and the pyramid rib 83 have a point-symmetrical shape when viewed in a plane.

Further, in the present invention, as shown in FIG. 7B, in the straight body portion 63b below the tapered portion 63a, a vertical groove 85 extending linearly in the axial direction is formed on the inner surface thereof. , It is preferable that a plurality of points are symmetrically formed. By forming such a vertical groove 85, a thin-walled portion that defines a shrinkage shape is formed in the bag-shaped portion 23 formed by blow molding in the portion corresponding to the vertical groove 85 in the axial direction. When the contents are discharged from the bag-shaped portion 23 and shrinkage occurs, it is possible to secure a stable shrinkage shape by using this thin-walled portion as a crease, and the shrinkage makes it difficult to discharge the contents. Can be avoided more reliably.
The vertical grooves 85 are not particularly limited, but it is usually desirable that the vertical grooves 85 are distributed point-symmetrically in a number of about 4 to 9.

The double-structured container 1 produced as described above is put into use by filling the inner bag container 5 with the content liquid and then attaching a cap.
As the cap attached to the double-structured container 1, in principle, a so-called screw cap attached to the outer cylinder neck portion 11 by screw engagement can also be used. In this case, a cap engaging screw is provided on the outer surface of the outer cylinder neck portion 11, and a slit for securing the air passage X is formed in the screw.

However, in the double-structured container 1 of the present invention, it is effective to bring the air valve A (specifically, the annular flap piece) formed on the cap into contact with the inclined surface 33 formed on the outer cylinder neck portion 11. In such an air valve A, as can be understood from FIG. 2, the inner bag neck portion 21 is located inside the air valve A. Therefore, in order to ensure the sealing of the inner bag container 5, it is necessary to use a member such as an inner ring C. From the viewpoint of ensuring such a structure, the cap applied to the double-structured container 1 of the present invention is preferably a plug-type cap. By applying such a plug-type cap, the height of the outer cylinder neck portion 11 and the inner bag neck portion 21 can be lowered, which is advantageous in terms of manufacturing cost.

Although the schematic structure of the stopper type cap 100 is shown in FIG. 2 described above, FIG. 10 shows a typical structure of the stopper type cap 100 mounted on the double-structured container 1 of the present invention. ..

In FIG. 10, the cap attached to the outer cylinder neck portion 21 of the double-structured container 1 by tapping is shown by 100 as in FIG. 2, and is formed on the outer surface of the air valve A and the outer cylinder neck portion 11. It includes an engaging protrusion B that engages with the undercut 31 and an inner ring C that is in close contact with the inner surface of the inner bag neck portion 21.

The cap 100 is composed of a cap body represented by 110 as a whole, an inner plug 111 held in the cap body 110, and a check valve 113.

The cap main body 110 has a tubular side wall 121 attached to the neck portion 11 of the outer cylinder container 3 described above, and an upper lid 123 hinged to the tubular side wall 121.

At the upper end of the tubular side wall 121, a top plate portion 125 extending so as to close the internal space thereof is integrally formed.
Further, although not particularly limited, the tubular side wall 121 is formed with slits 127 extending from above to below, thereby forming a double wall structure. With such a double wall structure, the used cap 100 can be easily peeled off from the double structure container 1 without using a special instrument, and the separate disposal property is improved. ..

Further, an engaging projection B that engages with the undercut 31 of the outer cylinder neck portion 11 is formed on the inner surface of the tubular side wall 121. As described above, the engaging projection B is formed with a notch for securing the air passage X.

An inner ring C extending downward is formed on the lower surface of the top plate portion 125 extending inward from the upper end of the tubular side wall 121 at a distance from the tubular side wall 121. When C is in close contact with the inner surface of the inner bag neck portion 21, the sealing property of the inner bag container 5 is ensured.

Further, an auxiliary protrusion 133 is formed from the outer peripheral edge of the lower surface of the top plate portion 125 to the upper end portion of the inner surface of the tubular side wall 121, and the auxiliary protrusion 133 is in close contact with the outer surface from the upper end surface of the outer cylinder neck portion 11. As a result, the cap body 110 (cylindrical side wall 121) is firmly fixed to the outer cylinder neck portion 11 without rattling. Needless to say, the auxiliary projection 133 is also formed with a notch in order to secure the air passage X.

Further, on the lower surface of the top plate portion 125, an annular hanging flap piece that functions as an air valve A is provided on the outer side of the inner ring C. The air valve A communicates with the straight space Y formed along the inner surface of the outer cylinder neck portion 11 by engaging with the inclined surface 33 formed on the upper end inner surface of the outer cylinder neck portion 11 described above. It can be used as an air passage X leading to the working space Z, and air is taken in and out of the working space Z through such an air passage X.
Therefore, instead of providing the air valve A as described above, an opening may be formed in the top plate portion 125, and an air valve having a form capable of opening and closing the opening may be provided. This is because the opening formed in the top plate portion 125 communicates with the straight space Y described above.

On the lower surface of the top plate portion 125 described above, an inner plug holding ring 137 (hereinafter, may be simply referred to as a ring) for holding the inner plug 111 is provided in a region surrounded by the inner ring C. The inner plug 111 is housed in the ring 137, but the ring 137 has a shape with a slightly reduced diameter downward so that the housed inner plug 111 is firmly held without falling off. A protrusion 139 is formed at the lower end of the inner surface of the ring 137. Further, a peripheral small protrusion 141 is formed on the lower surface of the top plate portion 125 on the inner side of the ring 137 in order to stably hold the inner plug 111.

On the other hand, on the upper surface of the top plate portion 125, a short upper lid engaging protrusion 143 is formed on the peripheral edge portion, whereby the upper lid 123 is firmly held when the upper lid 123 is closed.

Further, a guide cylinder 145 for pouring out the content liquid is erected at the center of the upper surface of the top plate portion 125.
The guide cylinder 145 communicates with the hollow space in the tubular side wall 121, and serves as a pouring path for the content liquid discharged from the inner bag container 5.

The upper lid 123 is rotatably connected to the upper end portion of the tubular side wall 121 or the outer peripheral edge of the top plate portion 125 by a hinge band 147.
The upper lid 123 is composed of a top plate portion 151 and a skirt portion 153 connected to the outer peripheral edge of the top plate portion 151.

In the upper lid 123, an engaging recess 155 is formed on the inner surface of the skirt portion 153, and when the upper lid 123 is swiveled and closed, the recess 155 engages with the above-mentioned upper lid engaging protrusion 143. As a result, the closed state of the upper lid 123 is stably maintained. Further, on the outer surface of the skirt portion 153, an opening tab 157 is provided at a position opposite to the hinge band 147. As a result, the tab 157 can be easily opened by holding the tab 157.

A tall cushioning protrusion 159 is formed in a circumferential shape on the inner surface (upper surface in FIG. 6) of the top plate portion 151. When the upper lid 123 is closed, the tip of the cushioning protrusion 159 is formed so as to abut on the upper surface of the top plate portion 125. That is, when a large vertical load is accidentally applied while the upper lid 123 is closed, the stress is relaxed by the cushioning protrusion 159, and the upper lid 123 and the like are prevented from being damaged.

Further, a pole 161 for energizing the check valve 113 is erected in the central portion of the top plate portion 151.
The pole 161 is a member for pressing and energizing the check valve 113 held by the inner plug 111 housed in the inner plug holding ring 137 when the upper lid 123 is closed. Therefore, when the upper lid 123 is closed, the pole 161 enters the content liquid injection guide cylinder 145 and comes into contact with the check valve 113. Therefore, the upper end of the guide cylinder 145 is formed to be short on the hinge band 147 side. Further, the pole 161 has a form in which the base portion side is formed with a relatively large diameter and the tip portion side is formed with a small diameter, and accordingly, the upper portion of the inner surface of the guide cylinder 145 is inwardly formed. A protruding inward protrusion 145a is provided. That is, when the upper lid 123 is closed, the pole 161 that has entered the guide cylinder 145 is firmly fixed at the base side of the large diameter by fitting with the inward protrusion 145a, and the tip side of the small diameter of the pole 161 is positioned. , It is configured to abut on the check valve 113 at a fixed position to urge the check valve 113.

Further, a small protective ring 163 is provided on the inner surface of the top plate portion 151 at a position that surrounds the pole 161 and that surrounds the guide cylinder 145 when the upper lid 123 is closed. As a result, when the content liquid adheres to the pole 161 and its peripheral portion, when the upper lid 123 is opened, the content liquid can be prevented from getting wet and spreading over the entire inner surface of the top plate portion 151. Further, for the same purpose, a small groove 165 is provided in the peripheral portion of the pole 161.

Further, the inner plug 111 is housed in the inner plug holding ring 137 provided on the cap body 110, and the inner plug 111 communicates between the inside of the guide cylinder 145 and the inside of the inner bag container 5. An opening 170 is formed in the central portion. That is, the content liquid in the inner bag container 5 flows into the guide cylinder 145 through the opening 170 and is discharged from the guide cylinder 145.

The inner plug 111 as described above extends downward from the tip of the tubular base 171 and the circumferential inclined flange 173 extending upward from the lower end of the inner surface of the tubular base 171 and the peripheral inclined flange 173. It is formed of a descending wall 175 and a horizontal flange 177 protruding inward from the lower end of the descending wall 175, and the space surrounded by the horizontal flange 177 is the above-mentioned opening 170. Such a form of the inner plug 111 is formed in order to stably hold the check valve 113 described below.

That is, in order to discharge the content liquid contained in the inner bag container 5, the opening 170 must be opened, but in the state where the opening 170 is not discharged, air is discharged into the inner bag container 5. The opening 170 needs to be closed to prevent inflow. This is because when air flows in, the contracted bag-shaped portion 23 swells due to the discharge of the content liquid, which hinders the subsequent discharge of the content liquid. Further, when the content liquid is discharged, the content liquid adhering to the inner surface of the guide cylinder 145 is prevented from returning to the inside of the inner bag container 5, and the content liquid is discharged in order to maintain the quality of the content liquid in the inner bag container 5. After that, it is desired that the opening 170 is closed promptly. A check valve 113 is used to ensure such a function.

The check valve 113 has a dome-shaped valve body 181 that is circular and bulges slightly upward, and the valve body 181 can be moved up and down by a plurality of straps 185 extending from the annular support member 183. It is held in. The annular support member 183 is fitted and fixed inside the inner plug holding ring 137, and the valve body 181 is inserted into the descent wall 175 so as to close the opening 170. When the valve body 181 rises, the opening 170 is opened and the content liquid is discharged through the opening 170. In this case, since the valve body 181 is held by the plurality of straps 185, the content liquid that has passed through the opening 170 flows into the guide cylinder 145 through the gap between the straps 185. Further, when the upper lid 123 is closed, the pole 161 described above firmly presses the valve body 181 so that the valve body 181 is fitted in the descending wall 175, and the opening 170 is firmly closed by the valve body 181. It will be in the state of being.

That is, by tilting the double-structured container 1 with the upper lid 123 open and pressing the body portion 15 (squeeze region) of the outer cylinder container 3, the bag-shaped portion 23 of the inner bag container 5 is pressed, at this time. The valve body 181 is lifted by the increase in the internal pressure of the valve body, and the content liquid is discharged through the opening 170 as described above. Further, when the squeeze of the body portion 15 is stopped, the valve body 181 returns to the position where the opening 170 is closed due to the elasticity of the strap 185, and further, by closing the upper lid 123, the valve body 181 is placed inside the descent wall 175. It will be held firmly.

The above-mentioned inner plug 111 and the check valve 113 are incorporated into the cap body 110. For example, after the check valve 113 is incorporated into the inner plug 111, the assembly is held in the inner plug of the cap body 110. This is done by pushing it into the use ring 137. As a result, the inner plug 111 accommodating and holding the check valve 113 has its tubular base 171 firmly sandwiched between the protrusion 139 at the lower end of the ring 137 and the peripheral small protrusion 141 above. In this state, with the upper lid 123 closed, the cap 100 is attached by covering the double-structured container 1 filled with the contents and tapping the cap 100.

By the way, when the upper lid 123 is opened and the body portion 15 of the outer cylinder container 3 is pressed to push up the valve body 181 of the check valve 113 and discharge the content liquid, the inner surface of the outer cylinder container 3 and the inner bag container are discharged. It is necessary to prevent air from being discharged from the working space Z between the working space Z and to introduce air into the working space Z after discharging the content liquid to return the working space Z to normal pressure. In the present invention, in order to ensure such a function, the above-mentioned air valve A (annular hanging flap piece) is provided so as to abut on the inclined surface 33 formed at the upper end on the inner surface of the outer cylinder neck portion 11. That is why.

The cap body 110, the inner plug 111, and the check valve 113 described above are all injection-molded using an olefin resin such as low-, medium- or high-density polyethylene, linear low-density polyethylene, or polypropylene. Manufactured by compression molding or the like.

The double-structured container 1 to which such a cap 100 is attached can dispense the content liquid, prevent oxidative deterioration due to contact with air, and maintain the quality of the content liquid for a long period of time. , Soy sauce and other seasonings are preferably used as containers.

The preferred embodiment of the double-structured container configured according to the present invention and the container lid 100 attached thereto have been described above with reference to FIGS. 1 to 10, but the double-structured container of the present invention has been described above. It is not limited to the embodiment, and various modifications can be considered without departing from the scope of the present invention. A modified example of the double-structured container of the present invention will be further described with reference to FIGS. 11 and 12.

FIG. 11 shows a schematic perspective view of the outer cylinder container according to a modified example of the double-structured container configured according to the present invention. In the above-described embodiment, as clearly shown in FIG. 3, the inclined surface 33 formed on the inner surface of the outer cylinder neck portion 11 is provided with the pressure adjusting recess 34, but in the modified example shown in FIG. Is provided with a pressure adjusting convex portion on the inclined surface 33'formed on the inner surface of the outer cylinder neck portion 11'. Explaining this with reference to FIG. 11 and FIG. 12, in the illustrated embodiment, the pressure adjusting convex portion is a ridge 34'protruding inward in the radial direction and extending in the circumferential direction. If desired, the pressure adjusting convex portion may be a protruding portion that locally protrudes inward in the radial direction at a predetermined position in the circumferential direction. A plurality of ridges 34'are provided at equal intervals in the circumferential direction (8 in the illustrated embodiment), and each ridge 34'is two air passages adjacent to each other when viewed in the circumferential direction. It is arranged between the forming grooves 37'. The number of ridges 34'may be only one instead of a plurality, but it is desirable that the number of ridges 34'is eight from the viewpoint of air movement described later. The vertical cross-sectional shape of the main portion of the ridge 34'(the portion excluding the auxiliary groove described later) is substantially triangular, and the upper surface 34a'and the upper surface 34a' extending in the radial direction inward from the inclined surface 33' It is provided with a hanging lower surface 34b ′ that hangs down substantially in the vertical direction from the radial inner end of ′. Further, in the illustrated embodiment, an auxiliary groove 38'extending in the vertical direction is locally formed in the ridge 34'(convex portion for pressure adjustment). The auxiliary groove 38'is arranged at the center of the ridge 34'in the circumferential direction (thus, the center of two adjacent air passage forming grooves 37' when viewed in the circumferential direction). The auxiliary groove 38'extends linearly in parallel with the inclined surface 33', and both the upper end and the lower end of the auxiliary groove 38'are open. Therefore, the auxiliary groove 38'is inclined inward in the radial direction and extends downward, and the upper end surface thereof is provided on the upper surface 34a'and the lower end surface is provided on the hanging lower surface 34b'.

In the double-structured container of this modified example, the inclined surface 33'formed on the inner surface of the outer cylinder neck portion 11'is provided with a ridge 34'(convex portion for pressure adjustment). Therefore, in the normal state and in the state where the working space (Z) is pressurized, the outer peripheral surface of the air valve (A) of the container lid does not come into close contact with the inner surface of the outer cylinder neck portion 11'over the entire circumferential direction, and the container The outer peripheral surface of the air valve (A) of the lid is the inner surface of the outer cylinder neck portion 11'on the hanging lower surface 34b'of the ridge 34'and the inclined surface 33'of the intermediate portion between the two ridges 34'adjacent in the circumferential direction. In the required area adjacent to both ends in the circumferential direction of the ridge 34', the protrusion 34'is separated from the inner surface of the outer cylinder neck portion 11'. Therefore, by providing the pressure adjusting convex portion, as in the pressure adjusting concave portion 34 shown in FIG. 3, gas is released when the pressure in the working space (Z) rises due to the change in environmental temperature (temperature rise). Can be done effectively.

When the content liquid is already discharged to some extent and air is present in the working space (Z), when further discharging the content liquid, the body of the outer container is squeezed in the same manner as the above-mentioned double-structured container. , The bag-shaped part of the inner bag container is pressed through the air layer existing between the bag-shaped part of the inner bag container and the body of the outer cylinder container (the operation when the content liquid is first discharged is described above. Since it is the same as the embodiment, the description thereof will be omitted). At this time, as described above, the outer peripheral surface of the air valve (A) of the container lid is separated from the inner surface of the outer cylinder neck portion 11'in the required region, so that the air in the air layer, that is, the action The air in the space (Z) passes through the required region and gradually flows out to the outside, but even in such a case, it is possible to press the bag-shaped portion of the inner bag container through the air layer. is there.

When the squeeze of the body portion is stopped, the body portion of the outer cylinder container recessed by the squeeze returns to the original shape and air flows into the working space (Z) from the outside, as in the case of the double-structured container described above. At this time, as described above, since the outer peripheral surface of the air valve (A) of the container lid is separated from the inner surface of the outer cylinder neck portion 11'in the required region, air is also discharged from the required region. It can flow into the working space (Z), which makes it possible to quickly return the body of the outer cylinder container from the recessed state to the original shape. Further, in the present embodiment, due to the auxiliary groove 38'formed in the ridge 34', the portion where the ridge 34'that is in close contact with the air valve (A) of the container lid is also formed. Air can flow into the working space (Z) through the auxiliary groove 38', and from this point as well, the body portion of the outer cylinder container can be quickly returned to the original shape from the recessed state.

In the double-structured container of this modification, the ridge 34'(convex portion for pressure adjustment) is provided on the inclined surface 33'formed on the inner surface of the outer cylinder neck portion 11'. As described above, under normal conditions, the outer peripheral surface of the air valve (A) of the container lid does not come into close contact with the inner surface of the outer cylinder neck portion 11'over the entire circumferential direction, and the air valve (A) of the container lid The outer peripheral surface is in close contact with the inner surface of the outer cylinder neck portion 11'on the hanging lower surface 34b'of the ridge 34'and the inclined surface 33'in the middle portion of the two ridges 34'adjacent in the circumferential direction, and the ridge 34' In the region adjacent to both ends in the circumferential direction (the required region), the outer cylinder neck portion 11'is separated from the inner surface. In other words, under normal conditions, the air valve (A) of the container lid is locally deformed in advance at the position where the ridge 34'is provided, and is deformed as compared with the case where it is not locally deformed in advance. It's easy. As a result, as compared with the case where the pressure adjusting recess 34 is provided on the inclined surface (that is, the case where the air valve (A) of the container lid cannot be locally deformed in advance), air can be discharged from the outside through the air passage (X) more quickly. ) Can flow into the working space (Z).

1: Double-structured container 3: Outer cylinder container 5: Inner bag container 11: Outer cylinder neck 13: Shoulder 15: Body 21: Inner bag neck 23: Bag-shaped 31: Undercut 33: Inclined surface 34: Pressure Adjustment recess 34': Pressure adjustment protrusion (protrusion)
35: Step surface 37: Groove for forming air passage 43: Ring-shaped protrusion for fitting and fixing 100: Cap X: Air passage Y: Straight space Z: Working space A: Air valve of cap

Claims (6)

In a double-structured container consisting of an outer cylinder container and an inner bag container housed inside the outer cylinder container,
The outer cylinder container has an outer cylinder neck portion and a body portion connected to the outer cylinder neck portion and formed by stretching.
The inner bag container has an inner bag neck portion and a bag-shaped portion connected to the inner bag neck portion and formed by stretching.
On the outer surface of the inner bag neck portion, a ring-shaped protrusion for fitting and fixing with the inner surface of the outer cylinder neck portion is provided in a lower portion.
On the inner surface of the outer cylinder neck portion of the outer cylinder container, an air passage forming groove for communicating the gap between the inner surface of the body portion of the outer cylinder container and the outer surface of the bag-shaped portion of the inner bag container with the outside is axially oriented. A double-structured container characterized by extending to. According to claim 1, a stepped surface for restricting the descent of the ring-shaped protrusion is formed on the inner surface of the outer cylinder neck portion, and the air passage forming groove is formed so as to at least straddle the stepped surface. The described double structure container. An inclined surface is formed on the inner surface of the outer cylinder neck portion in a form that is continuous with the upper end surface and has a reduced diameter as it goes downward, and the air passage forming groove is inclined at least until it straddles the stepped surface. The double-structured container according to claim 2, which extends downward from the lower end of the surface. The double-structured container according to claim 3, wherein the inclined surface is an engaging surface with an air valve provided on the cap, and a pressure adjusting recess is formed on the inclined surface. The double-structured container according to claim 4, wherein the pressure adjusting recess has a shape in which the upper portion is wide. The double-structured container according to claim 3, wherein the inclined surface is an engaging surface with an air valve provided on the cap, and a convex portion for pressure adjustment is formed on the inclined surface.