JP5168572B2 - Blow molded container and molding method thereof - Google Patents

Description

  The present invention relates to a synthetic resin blow-molded container in which an outer layer and an inner layer are detachably laminated and a molding method thereof.

  Patent Document 1 discloses a blow molding called a so-called delamination container, in which an inner layer forming a shrinkable and deformable content body is detachably laminated in an outer layer forming an outer shell-like outer container. An invention relating to a container is described. This type of delamination container is a squeeze-type dispensing container that contains a liquid containing cosmetics, food, etc. in its contents and is combined with a cap provided with a check valve, and a dispensing container that is combined with a manual pump. It is used as

In addition, in the dispensing container using the delamination container as described above, when the content liquid is poured out, the inside of the contents body is in a reduced pressure state, and the contents body is reduced from the outer layer while the inner layer is separated from the outer layer. Combined with the action effect of the valve, it is possible to prevent the outside air from entering the contents body, and it is possible to suppress the contact with air and effectively suppress the deterioration of the contents liquid.
In addition, it is possible to maintain the original shape after pouring because the external air is introduced between the outer layer and the inner layer as much as the volume of the content body is reduced and deformed after pouring. It can be set as the extraction container which has the outstanding performance also in terms of surface and appearance.
JP-A-8-26241

The above delamination container is generally formed by co-extrusion of a multilayer parison in which an outer layer and an inner layer made of resins having different adhesive properties, such as polyolefin resin and nylon resin, are laminated. Obtained by blow molding a parison.
In addition, a stacked preform in which an outer preform is injection-molded using the inner test preform in the test tube as an insert material, or a stacked preform in which the inner preform is inserted into a pre-injected test tube outer preform is biaxially stretched. There is also a blow molding method.

Here, in the method of biaxial stretching blow molding of the above-mentioned stacked preform, if the outer preform and the inner preform are made of different resins, the heating temperature and stretching conditions suitable for biaxial stretching differ depending on the resin, Combinations of resins and stretching conditions are limited. On the other hand, if both the preforms are made of the same type of synthetic resin, there is a problem that the outer preform and the inner preform are welded when the preform is heated, and a delamination container cannot be obtained.
In particular, a biaxially stretched blow container made of polyethylene terephthalate (hereinafter abbreviated as PET) resin is a container that has the requirements of strength, gas barrier properties, transparency, and relatively low cost. Delamination containers made of PET resin by axial stretch blow molding are expected to develop a wide range of applications.

  Then, this invention makes it a subject to provide the biaxial stretch blow molding container which laminated | stacked the outer layer and inner layer which consist of synthetic resins, such as PET resin, so that peeling was possible.

Of the means for solving the above problems, the main configuration of the blow molded container of the present invention is:
Biaxially stretched blow-molded stack preforms in which outer preforms and inner preforms made of the same kind of synthetic resin are stacked in close contact via a release agent layer,
The inner layer, which is made of the same kind of synthetic resin as the outer layer and forms a freely deformable content body, adheres to the inner side of the outer layer forming the outer container via a release agent layer formed of heat-resistant silicone oil. It is said that they are laminated in a shape.

In the above configuration, the outer preform and the inner preform are simultaneously biaxially stretch blow molded to form the outer layer and the inner layer forming the outer container and contents of the container, but the outer preform and the inner preform are separated via the release agent layer. By stacking, the outer body and the inner body can be separated through the release agent layer without the outer body and contents being welded even after the preheating process of the stacked preform and the biaxial stretch blow process. To obtain a blow molded container laminated in close contact with each other,
As a result, it is possible to provide a delamination container made of the same kind of resin in the outer layer and the inner layer by appropriately making the inner layer relatively thin and making the contents deflated and deformable.

  Here, the outer layer and the inner layer do not necessarily have to be laminated so as to be peelable through the release agent layer over the entire region, and the outer preform and the outer layer are formed in a portion excluding a predetermined region depending on the purpose of use. Inner preforms can be stacked via a release agent layer. In a biaxially stretched blow molded container, the outer layer and inner layer can be bonded and fixed at a portion corresponding to this predetermined area. It is also possible to control the volume-reducing deformation mode of the content body.

  The release agent layer can be applied in advance to the inner peripheral surface of the outer preform and the outer peripheral surface of the inner preform, and various materials including a mold release agent can be used. Among these, the use of heat-resistant silicone oil is preferable from the viewpoints of coatability, heat resistance and stretchability in the biaxial stretch blow molding process, and stability and safety as a chemical product.

  Still another configuration of the present invention is that, in addition to the above main configuration, the outer layer and the inner layer are made of PET resin.

  By making both the outer preform and the inner preform made of PET resin, the outer layer and inner layer of the container can be made of PET resin, but this is strength, gas barrier property, transparency and relatively low cost. It is possible to provide a delamination container made of PET resin by biaxial stretch blow molding that also has the above requirement.

Next, the main molding method relating to the blow molded container of the present invention is as follows.
Using outer and inner preforms made of the same type of synthetic resin ,
Apply a heat-resistant silicone oil to the inner peripheral surface of the outer preform or the outer peripheral surface of the inner preform in advance to form a release agent layer, and insert the inner preform into the outer preform, and then the outer preform and inner preform. This is a biaxial stretch blow molding of a stacked preform obtained by stacking in a close contact state through a release agent layer.

  According to the above molding method, even if the outer preform and the inner preform are made of the same kind of synthetic resin by stacking the outer preform and the inner preform in close contact via the release agent layer, The outer body and contents are not welded even after the pre-heating step of the stacked preform and the biaxial stretch blow step, and the outer layer and inner layer made of the same kind of synthetic resin are in close contact with each other through the release agent layer. A blow molded container laminated in a shape can be provided.

Still another molding method of the present invention uses an outer preform (111) and an inner preform (121) made of the same kind of synthetic resin,
It is said that a stacked preform obtained by injection-molding an outer preform with an inner preform coated with heat-resistant silicone oil as a release agent layer on the outer peripheral surface is subjected to biaxial stretch blow molding .

Two forming methods are described in accordance with a specific method for preparing a stacking preforms stacked adhesion form the outer preform and the inner preform made same kind of the synthetic resin through the release agent layer Is.
In addition, as a method of apply | coating heat resistant silicon oil to the outer peripheral surface or inner peripheral surface of a preform, methods, such as apply | coating so that it may be spray-coated, and being immersed in silicon oil, are employable.

Since the present invention has the above-described configuration and method, the following effects can be obtained.
In the case of the main structure of the present invention, the outer preform and the inner preform are stacked in advance through the release agent layer, so that the pre-heating step of the stacked preform and the biaxial stretch blow are performed. Even after passing through the process, the outer body and the contents are not welded, and a blow molded container in which the outer layer and the inner layer are laminated in a close contact state through the release agent layer can be obtained. By making it relatively thin, it is possible to provide a delamination container made of the same type of resin in the outer and inner layers.

  In the case where the outer layer and the inner layer are made of PET resin, a delamination container made of PET resin by biaxial stretch blow molding having the requirements of strength, gas barrier property, transparency and relatively low cost is provided. be able to.

Further, in the main molding method according to the present invention relating to the blow molded container,
Pre-heating the stacked preforms by stacking the outer and inner preforms in close contact via the release agent layer, even if the outer and inner preforms are made of the same type of synthetic resin. The blow molded container in which the outer body and the contents are not welded even after the process or the biaxial stretching blow process, and the outer layer and the inner layer of the same type of synthetic resin are laminated in a close contact state through the release agent layer. Can be provided.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below along the examples with reference to the drawings.
FIG. 1 is a half longitudinal front view showing an embodiment of the blow molded container of the present invention. This container 1 is a casing made of PET resin by a biaxial stretch blow molding method, and has a mouth tube portion 2, a cylindrical body portion 3, and a bottom portion 4, and a neck ring 5 at a lower end portion of the mouth tube portion 2. Is attached.

  The container 1 is a double container comprising an outer container 6 that forms an outer shell made of PET resin and a content body 7 that forms a relatively thin-walled inner bag that contains the content liquid. The outer layer 6a to be formed and the inner layer 7a to form the content body 7 are laminated so as to be peelable through a release agent layer 9 made of heat-resistant silicone oil, as shown in a partially enlarged view in the figure. It is a transparent container as a whole.

FIG. 2 is a front view partially showing a test tube stacking preform 101 used for forming the container 1 of FIG. 1 in a longitudinal section, and includes a mouth tube portion 102, a neck ring 105, and a cylindrical body portion 103. , Has a bottom 104.
Each of the stacked preforms 101 is made of a PET resin, and is formed from a test tubular outer preform 111 and a relatively thin inner preform 121. As shown in the partially enlarged view in FIG. The preform 111 and the inner preform 121 are laminated in close contact via a release agent layer 109 made of heat-resistant silicone oil.

  This stacked preform 101 is obtained by injection-molding an outer preform 111 using an inner preform 121 having a heat-resistant silicone oil applied as a release agent layer 109 on the outer peripheral surface as an insert material. The container 1 of FIG. 1 can be obtained by axial stretch blow molding.

Here, when preparing the stacked preform 101, it is possible not to apply heat-resistant silicone oil to a predetermined region, for example, the outer peripheral surface of the bottom of the inner preform 121. In the stretch blow step, the outer preform 111 and the inner preform 121 can be welded at the bottom 104, and the outer layer 6a and the inner layer 7a can be partially bonded and fixed in the bottom 4 region of the container 1.
And it is also possible to control the volume reduction deformation of the content body 7 to be described later by using such a partial adhesive fixing part in a predetermined manner.

  The method for manufacturing the stacked preform 101 as shown in FIG. 2 is not limited to the insert molding as described above. For example, the outer preform 111 and the inner preform 121 are previously injection molded, A method of applying heat-resistant silicone oil to the inner peripheral surface of the outer preform 111 or the outer peripheral surface of the inner preform 121 and fitting the inner preform 121 into the outer preform 111 can also be employed.

Next, FIG. 3 is a front view showing a delami-type dispensing container using the container 1 of the present invention shown in FIG. A manual push-down pump P is tightly attached to the cylindrical portion 2 by a cap body 22 and a packing 23.
A pair of intake holes 8 for introducing outside air between the outer layer 6a and the inner layer 7a are formed in an axially symmetrical manner in the outer layer 6a portion of the mouth tube portion 2 of the container 1.

  FIG. 4 shows a wiping of the inner layer 7a of the container 1 in a state in which the content liquid L is poured into the content body L of the container 1 of the dispensing container 21 shown in FIG. It is explanatory drawing which shows the mode of only deformation | transformation (volume reduction deformation | transformation).

Here, the container 1 has a structure in which an outer layer 6a and an inner layer 7a are laminated in close contact with each other through a release agent layer 9 made of heat-resistant silicone oil. Is in a depressurized state, and while the inner layer 7a is peeled from the outer layer 6a, the content body 7a is deformed and deformed in a deflated state as shown in FIG.
At the same time as the volumetric deformation of the content body 7, outside air enters between the outer layer 6 a and the inner layer 7 a through the intake hole 8, and the outer body 6 can maintain its original shape without being deformed by volume reduction. it can.

  Next, FIG. 5 is a longitudinal sectional view for explaining another example of use of the blow molded container of the present invention. According to the present invention, the outer layer 6a and the inner layer 7a are both made of a heat-resistant silicone oil. This is an example in which a blow molded container by delamination type biaxial stretch blow molding laminated in a close contact state so as to be peeled is inverted and used in a liquid supply apparatus.

The container 1 has a mouth tube part 2, a body part 3, and a bottom part 4, and a bottom part 4a for injecting compressed air from the air compressor AC is provided in the bottom part 4. An opening / closing mechanism VE provided with a valve is assembled and fixed so as to open and close the bottom opening 4a by an electric signal.
Further, a pouring nozzle NC with a check valve is installed in the mouth tube portion 2 located at the lower end.

  When the content liquid L is poured out, the switch provided appropriately is turned on, so that the opening / closing mechanism VE is opened and the compressed air from the air compressor AC is moved between the outer body 6 and the content body 7 of the container 1. The pressure is applied to the content body 7 and the content liquid L is poured out from the pouring nozzle NC. When the switch is turned off, the opening / closing mechanism VE is closed and the dispensing of the content liquid L is stopped by the check valve of the dispensing nozzle NC.

  Here, FIG. 5 shows a state in which about half of the content liquid L has been poured out. As the content liquid L is poured out, the inner layer 7a is peeled off from the outer layer 6a and the content body 7 is deflated. As the volumetric deformation of the liquid progresses, the checkout valve can prevent the backflow of air into the contents body 7 and smoothly proceed with the dispensing operation. Reduction can be effectively suppressed.

In this way, a Delami type container consisting of an outer layer and an inner layer made of PET resin by biaxial stretch blow molding can suppress the inflow of air into the content liquid due to the dispensing of the content liquid using the peelability. Of course, it is possible to provide a container having transparency, strength, gas barrier property, scientific stability and food hygiene at a relatively low cost. For example, a supply device for beverages such as juice It also has the performance required for a liquid container used in
Further, the state of the content liquid and the liquid level can be observed or measured using transparency.

In the usage example shown in FIG. 5, the container 1 is turned upside down, pressurized air is supplied from the bottom port portion 4 a located above, and the content liquid L is poured out from the mouth tube portion 2 located below. Since the container 1 has a configuration in which the content body 7 is reduced in volume, of course, the container 1 is made upright, and compressed air is supplied from the bottom port portion 4a located below, and the mouth tube portion located above. 2, the content liquid L can be poured out from the container 2, and in the apparatus having such a configuration, the contents of the container 1 are reversed as shown in FIG. A space is formed in the lower part, and the content liquid L can be unevenly distributed in the upper part.
In the example of use shown in FIG. 5, the content liquid is started and stopped by turning on and off the switch. However, the content liquid can be automatically supplied in a predetermined amount.
Further, it is possible to use such as controlling the supply of compressed air from the air compressor AC to make the inside of the container 1 have a constant pressure, for example, supplying the content liquid at a constant speed.

As mentioned above, although embodiment of this invention was described along the Example, embodiment of this invention is not limited to these Examples.
In the above example, the container is made of PET resin, but synthetic resin suitable for biaxial stretch blow molding such as polypropylene resin can be used .
Also, a description has been given of an example in which a pouring container in combination with a pressing pump container of the present invention in the embodiment shown in FIG. 3, pouring the squeeze type in combination with a cap which is disposed a check valve suitably It can also be a container.

The blow molded container of the present invention is an unprecedented biaxial stretch blow molded container in which an outer layer and an inner layer made of the same kind of synthetic resin such as PET resin are detachably laminated, and a wide range of application development is expected as a delamination container. .

It is a half vertical front view which shows one Example of the blow molding container of this invention. It is a front view which partially shows longitudinally the preform used for carrying out the biaxial stretch blow molding of the container of FIG. It is explanatory drawing which shows an example of the extraction container which uses the container of FIG. FIG. 4 is an explanatory view showing a volume reduction deformation state of an inner layer in the dispensing container of FIG. 3. It is a longitudinal section explaining the other usage example of the blow molding container of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1; Container 2; Mouth part 3; Body part 4; Bottom part 4a; Bottom mouth part 5; Neck ring 6; Outer body 6a; Outer layer 7;
9; Release agent layer 21; Pouring container 22; Cap body 23; Packing 101; Stack preform 102; Mouth tube portion 103; Body portion 104; Bottom portion 105; Neck ring 109; ; Inner preform P; Pump AC; Air conditioner presser VE; Opening / closing mechanism NC;
L: Contents liquid

Claims (4)

A biaxially stretched blow-molded outer preform made of the same kind of synthetic resin and a stacked preform in which inner preforms are stacked in close contact with each other via a release agent layer, forming an outer container (6) Inside the inner layer (6a), a release agent layer (7a) made of a heat-resistant silicone oil, which is made of the same type of synthetic resin as the outer layer (6a) and forms an inner body (7) that is deflated and deformable ( 9) Blow-molded container laminated in a close-contact state so as to be peeled off. The outer layer (6a) and blow-molded container of claim 1, wherein the inner layer (7a) was made of a polyethylene terephthalate resin. Use the outer preform (111) and inner preform (121) made of the same kind of synthetic resin ,
A heat-resistant silicone oil is applied in advance to the inner peripheral surface of the outer preform (111) or the outer peripheral surface of the inner preform (121) to form a release agent layer (109), and the outer preform (111) The inner preform (121) is inserted, and the outer preform (111) and the inner preform (121) are stacked in close contact with each other through the release agent layer (109). A method for forming a blow-molded container, comprising performing axial stretch blow molding. Use the outer preform (111) and inner preform (121) made of the same kind of synthetic resin ,
The inner preform (121) coated with heat-resistant silicone oil as the release agent layer (109) on the outer peripheral surface is used as an insert material, and the stacked preform (101) obtained by injection molding the outer preform (111) is biaxial. A method for forming a blow-molded container, which comprises stretch blow molding.

Images