JP2004231280A - Synthetic resin container - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a delamination container, on which a single-direction valve for guiding in the fresh air between an outer layer and an inner layer is formed easily and securely at low cost. <P>SOLUTION: A container body has a bottom, on the surface of which a bottom seal part formed along a parting line is formed, and the bottom seal part is made to delaminate to form an air inlet. A bottom-attached synthetic resin cylindrical body having heat shrinkability and the single direction valve is fitted airtightly on the bottom of the container body. In this manner, the air inlet having the single-direction valve for guiding in the fresh air between the inner and outer layers is formed easily to provide the delamination container of a squeeze type simply at a low cost. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
TECHNICAL FIELD The present invention relates to a blow-molded synthetic resin container in which an inner layer forming a deformable inner bag is formed in an outer layer forming an outer shell in a releasable manner, that is, a so-called delami container.
[0002]
[Prior art]
2. Description of the Related Art A blow-molded container generally called a delami container is known in which an inner layer forming a deformable inner bag is releasably laminated within an outer layer forming an outer shell. The blow molded container is obtained by extruding an outer layer and an inner layer having almost no compatibility into a multilayer parison by co-extrusion, and blow molding the multilayer parison.
[0003]
The outer layer of the Delami container has an air inlet formed between the outer layer and the inner layer to allow the outside air to enter.It can be used with a cap combined with a dispenser pump, or the outer layer can be squeezed and restored. It is used as a squeeze type delami container by forming a flexible outer shell, arranging a check valve in the intake hole, and screwing a cap having an opening in which the check valve is arranged.
[0004]
The bottom seal part of the bottom part crushed and formed by the pinch-off part of the blow mold basically has a laminated structure of the outer layer part and the inner layer part with almost no compatibility, so bottom cracks easily occur in the outer layer part Therefore, research and development for securing the mechanical strength of the bottom portion of the delami container have been conventionally performed.
[0005]
In Patent Document 1, a bottom seal portion formed by being crushed flat by a pinch-off portion of a blow mold is formed into a ridge shape along a parting line by polymerizing and pressing a pair of rib pieces. There is a description of a technology in which a plurality of bite portions that bite from one side of a pair of rib pieces to the other are provided in a strip.
[0006]
In this conventional technique, the bottom seal portion is formed into a ridge shape having a height width, so that the pressure-bonded area between the outer layer and the inner layer in the bottom seal portion is increased, and the outer layer and the inner layer are formed by providing a plurality of biting portions. Not only further increase the crimping area, but also dramatically increase the resistance to shearing force parallel to the crimping surface, making it possible to obtain a bottom seal with high mechanical strength, which is unlikely to cause bottom cracks. I have.
[0007]
On the other hand, in the synthetic resin bottle described in Patent Document 2, the slit formed in the bottom seal portion due to the bottom crack was positively used as an inlet for outside air between the outer layer and the inner layer, that is, an air inlet. In order to secure the mechanical strength of the bottom, a bottomed cylindrical base cap is externally fitted to the bottom. In addition, when used as a squeeze-type delamination container, this base cap is tightly assembled to the bottom, and a check valve is attached so that the air between the outer layer and the inner layer in the squeeze operation can be discharged to the outside. I try not to be done.
[0008]
[Patent Document 1]
JP-A-8-216238.
[0009]
[Patent Document 2]
JP-A-2002-36344.
[0010]
[Problems to be solved by the invention]
Depending on the purpose of use, there are many cases where the above-mentioned intake hole is formed not in the bottom seal part but in the trunk part or the mouthpiece part, especially when used as a squeeze type delami container, between the outer layer and the inner layer when squeezing. A check valve is provided at the intake port to prevent certain air from being exhausted to the outside. In this case, if a bottom crack occurs in the bottom seal portion, air between the outer layer and the inner layer leaks from the cracked portion, and the squeeze operation cannot be performed smoothly.Therefore, the bottom seal is an essential condition. Even if the bottom cracks, the bottom needs to be sealed from the outside by some method.
[0011]
However, in the conventional technique for eliminating bottom cracks described in Patent Literature 1, the bottom seal portion has a large height width and thickness, so that its volume becomes large, so that it takes a long time for cooling, and There is a problem that the production efficiency is made extremely low. In addition, it is necessary to process the cap or the like to provide an intake port.
[0012]
Further, the conventional technique described in Patent Document 2 has a problem that the shape of the vicinity of the bottom of the container body becomes complicated and that the manufacturing cost of the base cap as a separate component is high.
[0013]
Therefore, the present invention has been made in order to solve the above-mentioned problems in the related art, and has as its object to provide a low-cost delami container.
[0014]
[Means for Solving the Problems]
The invention according to claim 1 of the present invention is
A synthetic resin container blow-molded from a cylindrical parison, comprising an outer layer and an inner layer forming a volume-reducible deformable inner bag laminated releasably on the outer layer, the container body having a bottomed cylindrical shape. On the bottom surface of the bottom, a bottom seal portion formed by being crushed by a pinch-off portion of a blow split mold is provided, and the bottom seal portion is peeled off between the outer layer and the inner layer and between the outer layer and the inner layer. A bottomed cylinder having a one-way valve formed of a heat-shrinkable synthetic resin, having an intake hole for introducing outside air, and having a one-way valve communicating with the intake hole and opening in a direction to introduce air into the intake hole. The container was externally sealed to the bottom of the container body to form a container made of synthetic resin.
[0015]
With this, a heat-shrinkable, bottomed cylindrical body made of a so-called shrink film made of a synthetic resin having a one-way valve is externally fitted to the bottom of the container body, and by applying heat to the bottom of the container body, A one-way valve that allows air to be introduced between the outer layer and the inner layer from the formed intake hole and does not discharge the air between these layers to the outside can be provided reliably, easily, and at low cost.
[0016]
That is, after the contents are poured out from the opening of the pouring cap body by the squeeze of the container body, when the squeeze is stopped and the pressing pressure is released, the contents are stopped to be poured out, and the outer layer is returned to its original state by the elastic recovery force. It begins to recover to its original shape, and the function of the check valve disposed on the pouring cap body stops the backflow of the contents into the inner container and the inflow of outside air, and the inner container keeps the reduced volume deformed state Therefore, external air is introduced between the outer layer and the inner layer through the intake hole formed in the bottom seal portion and the one-way valve provided in the bottomed cylindrical body, and the outer layer is restored to the original shape. .
[0017]
When the outer layer is restored to its original shape and the body of the container is squeezed again, the function of the one-way valve is exhibited, and the air between the outer layer and the inner layer is sealed, so the squeeze operation is smoothly achieved can do.
[0018]
Furthermore, since the bottom is sealed by the heat-shrinkable bottomed tubular body, even if the inner layer is broken at the seal portion, the contents can be prevented from scattering around.
[0019]
According to a second aspect of the present invention, in the first aspect of the present invention, a diameter-reduced portion having an upwardly-reduced diameter for locking a bottomed tubular body is provided on the bottom tubular portion.
[0020]
According to the second aspect of the present invention, the bottomed tubular body in the heat-shrinked state is tightly fitted and locked to the reduced-diameter portion provided at the bottom of the container body. Of the bottomed cylindrical body can be reliably fixed to the bottom of the container body.
[0021]
According to a third aspect of the present invention, in the first aspect of the invention, a peripheral groove for locking the bottomed cylindrical body is provided in the bottom cylindrical portion.
[0022]
According to the third aspect of the present invention, in the circumferential groove, the bottomed tubular body in the thermally contracted state is securely locked, and the vertical movement of the bottomed tubular body is reliably suppressed. The bottom cylindrical body can be securely fixed to the bottom of the container body.
[0023]
According to a fourth aspect of the present invention, in the first, second or third aspect of the present invention, the bottom of the container body has an annular grounding portion serving as a grounding portion at a peripheral edge, and a concave portion inward at the center from the annular grounding portion. It had a shape having a flat portion formed at an uneven position.
[0024]
According to the invention as set forth in claim 4, the tip of the bottom seal portion formed in the ridge on the bottom surface of the bottom can be positioned higher than the annular grounding portion, and the bottomed tubular body is thermally contracted. The bottom surface of the bottomed cylindrical body is formed flat, and good grounding properties (sitting properties) can be obtained.
[0025]
DETAILED DESCRIPTION OF THE INVENTION
An embodiment of a synthetic resin container according to the present invention will be described with reference to the drawings.
[0026]
FIG. 1 shows a synthetic resin container 100. The synthetic resin container 100 is a squeeze-type dispensing container, and a dispensing cap body 20 is screwed to the mouthpiece 5 of the container body 1.
[0027]
The synthetic resin container 100 is composed of a container body 1 and a bottomed cylindrical body 13. The container body 1 is made of nylon having almost no compatibility with the outer layer 2 made of low-density polyethylene resin and the low-density polyethylene resin. This is a laminated structure with an inner layer 3 made of a resin, and is obtained by blow molding a parison in which two layers are laminated.
[0028]
The overall shape of the container body 1 is a cylindrical bottle, which is composed of a mouthpiece portion 5, a body portion 6 and a bottom portion 7 on which threads are engraved. The height of the container body 1 is 150 mm and the diameter of the body portion 6 Is 40 mm, and is used as a squeeze type pouring container by screwing a pouring cap body 20 to be described later into the mouthpiece section 5. For this reason, the outer layer 2 is formed to be relatively thick so as to form a squeezable deformable and resilient outer shell having flexibility, and the inner layer 3 is formed to be relatively thin so as to form a volume-reducing and deformable inner bag. .
[0029]
Three circumferential grooves 8b are formed in the cylindrical portion 8 of the bottom portion 7, and the bottom surface is depressed inward from the ring-shaped grounding portion 9 at the center and the ring-shaped grounding portion 9 at the center. The shape has a flat portion 10 formed at a position. Further, as shown in FIG. 2, along the parting line PL, a bottom seal portion 11 crushed flat by a pinch-off portion of a blow split mold is formed.
[0030]
FIG. 4A is a longitudinal sectional view of the vicinity of the bottom seal portion 11, and has a cross-sectional structure in which the inner layer 3 is sandwiched between a pair of outer layers 2 from both sides at the distal end of the bottom seal portion 11. The outer layer 2 and the inner layer 3 are laminated so as to be peelable with little adhesion between them. For example, when a force is applied from both sides, the outer layer 2 and the inner layer 3 are peeled off as shown in FIG. An intake hole 15 for introducing outside air is formed between the inner layer 3 and the inner layer 3. The suction holes 15 may be formed for each container body 1 or may be formed by a pressure at which a bottomed tubular body 13 described later is attached by thermal contraction.
[0031]
The bottomed tubular body 13 is made of a heat-shrinkable film made of a synthetic resin, and is formed in a bottomed cylindrical shape as shown in FIG. The diameter of the bottomed cylindrical body 13 is slightly larger than the diameter of the bottom 7 of the container body 1 and can be fitted in the bottom 7 with a margin as it is, and the height of the side surface is at least the height reaching the circumferential groove 8b. Has become.
[0032]
A one-way valve 19 is provided on the bottom surface of the bottomed cylindrical body 13. The one-way valve 19 is composed of a hole 18 opened on the bottom surface and a valve membrane 17 provided to be openable and closable so as to close the hole 18 from the inside, and the outside air is introduced by moving the valve film 17 from the lower portion of the bottom surface. However, from the inside, the valve membrane 17 comes into close contact with the hole 18 and blocks the flow. The material of the valve membrane 17 may be a heat shrinkable film or another film. The attachment of the valve membrane 17 may be performed by any method such as adhesion and welding.
[0033]
The bottomed cylindrical body 13 is attached by fitting the bottomed bottom body 13 from below, and heating the periphery of the bottomed cylindrical body 13 to shrink the heat-shrinkable film so as to fit along the outer peripheral surface of the bottom part 7, particularly the circumferential groove 8a. And stick it together. Thereby, the bottomed cylindrical body 13 is attached to the outer periphery of the bottom 7 in a sealed state. Further, the bottomed cylindrical body 13 has a tight bottom surface, so that the bottom surface does not easily bend due to an increase in the internal pressure in the container body 1 and it is necessary that the rise in the internal pressure is not absorbed.
[0034]
The bottomed cylindrical body 13 may be heated by heating the entire bottomed cylindrical body 13, but it is necessary to heat at least the function of the one-way valve 19 so as not to be impaired. Further, even when the bottom surface of the bottomed tubular body 13 contracts, for example, the valve membrane 17 of the one-way valve 19 is fixed to the bottom surface of the bottomed tubular body 13 at one point, the valve membrane 17 and the bottom surface of the bottomed tubular body 13 are in contact with each other. The hole 18 is formed so that no gap or the like is formed between the holes 18.
[0035]
The pouring cap body 20 has a cap main body 21 of a topped cylindrical body and a pouring cylinder 27, an opening 23 is provided at a central portion on a top wall of the cap main body 21, and a container main body is provided on an inner peripheral surface. A screw thread for screwing with the opening 3 is engraved, and on the upper surface of the top wall of the cap body 21, a pouring cylinder 27 is provided so as to be erected and connected to the opening edge of the opening 23. ing. A check valve 25 is disposed in the opening 23. The check valve 25 normally closes the opening 23 to prevent invasion of air from the outside, backflow of contents, and the like, and squeeze the container body 1. In this case, the inner bag is opened by the inner pressure of the inner bag formed by the inner layer 3, the opening 23 is opened, and the contents are poured out.
[0036]
The dispensing cap body 20 is formed by screwing a sealing cylinder piece 28 hanging down on the lower surface of the top wall of the cap body 21 and a sealing part 24 attached to the lower end of the inner peripheral surface by screwing. When attached to the container body 1, the container body 1 is tightly attached to the upper end of the inner peripheral surface and the lower end of the outer peripheral surface of the mouthpiece portion 5 of the container body 1 to seal the attachment with the container body 1. Further, a cover cap 29 is detachably provided at the spout 22, and is usually covered with the cover cap 29.
[0037]
Next, the operation of the synthetic resin container 100 will be described. A bottomed cylindrical body 13 is tightly attached to the synthetic resin container 100, and an intake hole 15 is formed in the bottom seal portion 11.
[0038]
When the body 6 of the container body 1 is pressed from both sides with the finger S as shown in FIG. 1, the inner layer 3 is deformed inward together with the outer layer 2, the check valve 25 is opened, and the contents are discharged from the spout 22 of the cap body 21. Discharged.
[0039]
When the pressure on the body 6 of the container body 1 is released, the outer layer 3 starts to restore its original shape due to the elastic recovery force, and the air between the outer layer 2 and the inner layer 3 is decompressed. As a result, the inner pressure in the inner layer 3 is reduced. Returns to the outside air pressure, the check valve 25 is closed, the contents are stopped, and the one-way valve 19 is opened while the inner layer 3 keeps the reduced volume deformed shape. , Outside air is introduced between the outer layer 2 and the inner layer 3, and the outer layer 2 is restored to its original shape. At this time, the separation between the outer layer 2 and the inner layer 3 proceeds, and the gap 16 gradually expands.
[0040]
When the body 6 of the container body 1 is pressed again from both sides with the finger S as shown in FIG. 1, the inner layer 3 is deformed inward together with the outer layer 2. At this time, the gap 16 is pressed, but since the one-way valve 19 is closed, the air in the gap 16 does not flow out, the volume of the inner layer 3 is reduced, the check valve 25 is opened, and the contents are discharged from the spout 22 of the cap body 21. Is discharged. Then, when the pressing by the finger S is released, the one-way valve 19 is opened, and the outside air is sent into the gap 16.
[0041]
Therefore, according to the synthetic resin container 100, since the bottomed cylindrical body 13 having the one-way valve 19 is densely attached to the bottom 7, the container main body 1 is opened from the intake hole 15 provided in the bottom seal portion 11. Since the outside air is introduced in response to the squeeze and is closed as needed, the function as the delami container can be surely exhibited easily and at low cost.
[0042]
FIG. 5 shows another embodiment of the synthetic resin container of the present invention. The difference between the synthetic resin container 101 and the synthetic resin container 100 is that the cylindrical portion 8 of the bottom portion 7 of the container body 1 is provided with a reduced diameter portion 8a, and the reduced diameter portion 8a whose diameter is reduced upward has a bottomed cylinder. The body 13 is locked.
[0043]
Further, in the synthetic resin container 101, an adhesive band 4 was provided on the parting line PL over the entire height range of the container main body 1, and the outer layer 2 and the inner layer 3 were bonded and fixed along the parting line PL.
[0044]
Therefore, in the synthetic resin container 101, the bottomed tubular body 13 is tightly fitted and locked along the reduced diameter portion 8 a formed in the tubular portion 8 in a heat-shrinked state, and the displacement in the vertical direction is ensured particularly. Can be prevented.
[0045]
As a means for securely locking the bottomed cylindrical body 13 to the bottom portion 7 by heat contraction, the peripheral groove 8b is described in the first embodiment, and the reduced diameter portion 8a is described in the second embodiment. The shape of is not limited to these, for example, depending on the purpose of use, the adhesion force of the bottomed cylindrical body 13, from the trunk 6 to the cylindrical part 8 of the bottom part 7, may be a regular cylindrical shape without unevenness, or It can also be frustoconical.
[0046]
In addition, the adhesive band 4 is provided over the entire height range of the container body 1 and the outer layer 2 and the inner layer 3 are bonded and fixed, so that the volume reduction deformation of the inner layer 3 is reduced to a certain form that does not cause reduction in the height direction. It is possible to provide a squeeze-type dispensing container in which the flow path of the contents is regulated by regulating the dispensing operation and the dispensing operation is performed more smoothly.
[0047]
In the above example, the squeeze bottle has the dispensing cap body 20 attached to the container main body 1. However, the present invention is not limited to this, and may be a pump-type container in which a pump is attached to the mouthpiece 5.
[0048]
【The invention's effect】
According to the first aspect of the present invention, a bottomed cylindrical body having a one-way valve formed of a heat-shrinkable synthetic resin, that is, a shrink film, is attached to the bottom of the container body by heating. Thus, the one-way valve can be easily provided at the bottom of the container body, and the delami container having the bottom seal portion as the intake hole can be provided reliably, easily, and at low cost.
[0049]
Further, even if the inner layer is broken at the seal portion, the contents can be prevented from scattering around.
[0050]
According to the second aspect of the present invention, the vertical movement of the bottomed tubular body is suppressed by engaging the thermally shrinkable bottomed tubular body in close contact with the reduced diameter portion. Therefore, the bottomed cylindrical body can be securely attached to the bottom of the container body.
[0051]
According to the third aspect of the present invention, in the circumferential groove, the heat-shrinkable bottomed cylindrical body is securely locked in a tightly contacted state, and the vertical movement of the bottomed cylindrical body is suppressed. The bottom tubular body can be securely attached to the bottom of the container body.
[0052]
According to the invention as set forth in claim 4, the tip of the bottom seal portion formed on the bottom bottom surface of the ridge can be positioned higher than the annular grounding portion, and the bottomed cylindrical body is thermally contracted. The bottom surface is formed flat, and good grounding properties (sitting properties) can be obtained.
[Brief description of the drawings]
FIG. 1 is a sectional view showing a state in which a pouring cap is attached to an embodiment of a synthetic resin container according to the present invention.
FIG. 2 is a bottom view showing the synthetic resin container of FIG. 1;
FIG. 3 is a perspective view showing an example of a bottomed cylindrical body used for the container of FIG. 1;
4 (a) and 4 (b) are enlarged vertical sectional front views of essential parts showing the vicinity of a bottom seal portion of the synthetic resin container of FIG.
FIG. 5 is a sectional view showing another embodiment of the synthetic resin container according to the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1; Container main body 2; Outer layer 3; Inner layer 4; Adhesive band 5; Mouth section 6; Trunk section 7; Bottom section 8; Cylindrical section 8a; Reduced diameter section 8b; Bottomed cylindrical body 15; vent hole 16; gap 17; valve membrane 18; hole 19; one-way valve 20; outlet cap body 21; cap body 22; outlet 23; opening 24; Part 25; Check valve 27; Discharge cylinder 28; Seal cylinder piece 29; Cover cap 100, 101; Synthetic resin container PL; Parting line S;

Claims (4)

A synthetic resin container blow-molded from a cylindrical parison, comprising an outer layer (2) and an inner layer (3) forming a volume-reducible inner bag laminated releasably on the outer layer (2). ,
A bottom seal portion (11) formed by being crushed and formed by a pinch-off portion of a blow split mold on the bottom surface of the bottom portion (7) of the bottomed cylindrical container body (1);
The bottom seal portion (11) has an air inlet (15) for separating the outer layer (2) and the inner layer (3) and introducing outside air between the outer layer (2) and the inner layer (3). )
A bottomed cylindrical body made of a heat-shrinkable synthetic resin and having a one-way valve (19) communicating with the intake hole (15) and opening in a direction for introducing air into the intake hole (15) ( (13) A container made of synthetic resin, wherein the container (13) is hermetically sealed on the bottom (7) of the container body (1). The cylindrical part (8) of the bottom part (7) is provided with a diameter-reduced part (8a) with a reduced diameter for locking the bottomed cylindrical body (13). 2. The synthetic resin container according to 1. The synthetic resin according to claim 1, wherein a circumferential groove (8b) for locking the bottomed tubular body (13) is provided in the tubular portion (8) of the bottom portion (7). Container. The bottom portion (7) is provided with an annular grounding portion (9) serving as a grounding portion at a peripheral portion of the bottom portion (7) and a flat portion formed at a center portion at a position depressed inward from the annular grounding portion (9). The synthetic resin container according to any one of claims 1 to 3, wherein the container is formed in a shape including a portion (10).

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