JP2012086530A - Method of manufacturing composite container - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of manufacturing a composite container which can suppress dispersion of the capacity or the external form of a storage part of individual products.SOLUTION: The method of manufacturing the composite container A constituted by a bottle shaped resin thin storage container (a) having a mouth part 14 and a storage part 12 for storing a liquid substance, a resin armor b fused integrally with the outer surface, and a cap member c attached to the mouth part 14 includes at least a process for preparing the resin thin storage container (a) and the cap member c attached to the mouth part 14 in advance, a process for entirely filling the inside of the resin thin storage container (a) with the liquid 20 and attaching the cap member c, a process for setting the resin thin storage container (a) filled with the liquid 20 in a die, a process for injecting molten resin into the die and integrally fusing the resin armor b on the outer surface of the resin thin storage container (a), and a process for taking out the molded composite container A. In the process for forming the resin armor b, the temperature of the liquid 20 is equal to or lower than 30°C just before injecting the molten resin.

Description

  The present invention relates to a method for producing a composite container used for containing liquid substances such as skin lotions, chemicals, and beverages.

  2. Description of the Related Art Conventionally, a container with a lid having excellent corrosion resistance and airtightness has been widely used as a container for storing liquid substances such as skin lotions, chemicals, and beverages. As these containers, those made of glass or resin are widely used.

  Glass containers have the advantages of being profound and high-quality, being transparent and visible inside. On the other hand, the resin container has the advantages that the inside can be visually recognized by using a resin having transparency, the impact resistance is excellent, and mass production is possible using a mold. Since both have their advantages, they are used according to the purpose.

By the way, the glass container has the above-mentioned advantages, but also has a disadvantage that it is easily broken by an impact during transportation or a drop during use.
In addition, since the resin container is light, it has a disadvantage that it does not have a profound feeling or a high-class feeling.

  Therefore, in Patent Document 1, as shown in FIG. 12, the resin outer body 104 is formed by overmolding the resin on the outer surface of the glass container 102, thereby providing a solid feeling and a high-class feeling. A composite container 100 has been developed that combines the advantages of glass and resin with excellent impact resistance.

  However, the composite container 100 combining such glass and resin is poorly recyclable because it is a combination of different materials, and is made of glass that is still located in the inner layer when a strong impact such as dropping is applied. The container 102 may be damaged, and there are still problems to be solved.

  Therefore, the present applicant is excellent in impact resistance while providing a solid feeling and luxury feeling by injecting molten resin on the outer surface of a thin resin container made of resin to form a thick resin outer casing. In addition, a composite container (Patent Document 2) and a manufacturing method (Patent Document 3) that have good recyclability and are capable of mass production have been developed.

  Such a composite container is manufactured by overmolding a molten resin on the outer surface of the thin-walled container and fusing it integrally with the thin-walled container in a state where the thin-walled container is filled with, for example, liquid. Thus, a device is devised so that the thin container is not deformed by the injection pressure of the molten resin in the mold.

JP-T-2004-527424 JP 2009-543732 A Japanese Patent No. 4377447

  By the way, in the above-described method for manufacturing a composite container developed by the present applicant, a resin sheathing body is formed by overmolding molten resin on the outer surface of the thin container in a state in which the liquid is filled in the thin container. Then, although it was possible to prevent deformation of the thin container due to the injection pressure of the molten resin, it was confirmed that slight variations occurred in the volume and outer shape of the container of the thin container of the molded composite container.

  Slight variations such as the volume and outer shape of the container of such a thin container are within the dimensional tolerance of ordinary general-purpose molded products, and are hardly a problem. For example, a composite container is used as a cosmetic outer container. When used, there is a difference in the amount of cosmetic liquid stored in the storage unit, or the full filling line when a predetermined amount of cosmetic liquid is stored slightly differs for each product, and the appearance May become irregular and impair the beauty. In particular, in the case of containers such as cosmetics that are conscious of aesthetics and luxury, slight variations in the volume and outer shape of the container are a problem.

Therefore, the present condition is that a method for manufacturing a composite container that can solve these problems is required.
The present invention has been made in view of such a current situation, and suppresses variations in the volume and outer shape of the housing portion among individual products, maintains a good external appearance, and has a high-class feeling without impairing the aesthetic appearance. It aims at providing the manufacturing method of a composite container.

The present invention was invented to solve the problems in the prior art as described above,
The method for producing the composite container (A) of the present invention comprises:
A bottle-shaped resin thin-walled container (a) having a mouth part and a container for containing a liquid substance, and the resin thin-walled container (a) on the outer surface of the resin thin-walled container (a) Manufacture of a composite container (A) comprising a resin outer package (b) integrally fused and a closure member (c) attached to the mouth of the resin thin container (a) A method,
The method for producing the composite container (A) is as follows:
Preparing a bottle-shaped resin thin-wall container (a) and a closure member (c) to be attached to the mouth of the resin thin-wall container (a) in advance;
Filling the entire thin resin container (a) with liquid, and mounting the closure member (c) on the mouth in this state;
Setting the bottle-shaped resin thin-walled container (a) filled with the liquid in a mold;
A molten resin is injected into a mold in which the resin thin container (a) is set, and a resin outer package (b) is integrally fused to the outer surface of the resin thin container (a). Process,
Opening the mold and removing the molded composite container (A);
Having at least
In the step of forming the resin sheathing body (b),
The temperature of the liquid filled in the thin resin container (a) is 30 ° C. or less immediately before injecting the molten resin into the mold.

  Thus, if the temperature of the liquid filled in the resin thin container (a) is 30 ° C. or less, the molten resin is contained in the resin thin container when the molten resin for the resin outer package (b) is injected. A good solidification rate can be obtained when the outer surface of (a) is touched and solidified.

  Therefore, the resin thin container (a) can be reliably prevented from being deformed by the injection pressure of the molten resin and causing a variation in the volume and outer shape of the container, maintaining a good appearance and a high-class feeling. The composite container (A) can be manufactured.

Moreover, the manufacturing method of the composite container (A) of the present invention includes:
In the step of forming the resin sheathing body (b),
The temperature of the mold is set within a range of 5 to 100 ° C.

  If the temperature of the mold is set within such a range, the liquid in the thin resin container (a) set in the mold does not evaporate at the time of molding, and the thin resin can be stored safely and reliably. A composite container (A) in which the resin sheathing body (b) is integrally fused to the outer surface of the vessel (a) can be produced.

Moreover, the manufacturing method of the composite container (A) of the present invention includes:
In the step of forming the resin sheathing body (b),
The injection pressure of the molten resin injected into the mold is set in the range of 100 to 2000 kg / cm ² .

  If the injection pressure of the molten resin is set within such a range, the composite container (A) in which the resin sheathing body (b) is integrally fused to the outer surface of the thin container (a) safely and reliably. Can be manufactured.

Moreover, the manufacturing method of the composite container (A) of the present invention includes:
In the step of forming the resin sheathing body (b),
The resin temperature of the molten resin injected into the mold is set within a range of 100 to 350 ° C.

  If the resin temperature of the molten resin is set in such a range, the composite container (A) in which the resin outer package (b) is integrally fused to the outer surface of the thin container (a) safely and reliably. Can be manufactured.

Moreover, the manufacturing method of the composite container (A) of the present invention includes:
The resin thin-walled container (a) has a thickness in the range of 0.1 to 2.0 mm.

  Such a thickness makes it difficult to see the boundary line with the thin resin container (a) when fused integrally with the resin sheathing body (b), so that the composite has excellent aesthetics and luxury. A container (A) can be manufactured.

Moreover, the manufacturing method of the composite container (A) of the present invention includes:
The thickness of the maximum part where the thickness of the resin sheathing body (b) is maximum is in the range of 3.0 to 50.0 mm.

  With such a wall thickness, a solid feeling like glass can be obtained, and the resin outer package (b) can have various three-dimensional shapes, so that it has excellent aesthetics and luxury. A composite container (A) can be provided.

Moreover, the manufacturing method of the composite container (A) of the present invention includes:
The liquid filled in the thin resin container (a) is one selected from water, an aqueous solution, a lotion, a chemical, and an organic solvent.
If it is such a liquid, the composite container (A) in which the resin outer package (b) is integrally fused to the outer surface of the thin container (a) can be manufactured safely and reliably.

Moreover, the manufacturing method of the composite container (A) of the present invention includes:
In the step of forming the resin sheathing body (b),
The molten resin injected into the mold is an ionomer resin of ethylene / (meth) acrylic acid copolymer.

  Since such a resin is suitable as a resin having high transparency, a resin outer package (b) having extremely high transparency can be obtained. Therefore, it is possible to obtain a composite container (A) having excellent aesthetics and luxury.

Moreover, the manufacturing method of the composite container (A) of the present invention includes:
The resin constituting the thin resin container (a) is at least one selected from polyester, polyamide and polyolefin resin.

  With such a resin, it becomes difficult to see the boundary line with the resin outer package (b), and the composite container (A) having an excellent aesthetic appearance can be obtained with a synergistic effect of both members, thereby increasing the sense of quality. .

  According to the composite container manufacturing method of the present invention, in the step of forming the resin sheathing body (b), the temperature of the liquid filled in the thin resin container (a) injects the molten resin into the mold. Since the temperature is 30 ° C. or less immediately before, the volume and outer shape of the housing portion of the thin resin container (a) is prevented from varying in each product, the appearance is kept good, and it has excellent aesthetics and luxury. Composite containers can be manufactured.

FIG. 1 is a perspective view of an embodiment of a composite container manufactured by the manufacturing method of the present invention. FIG. 2 is a cross-sectional view of an example of a composite container manufactured by the manufacturing method of the present invention. FIG. 3 is a process diagram for filling the resin thin container (a) with the liquid and mounting the plugging member. FIG. 3 (a) shows a state in which the resin thin container (a) is prepared. FIG. 3 (b) is a view showing a state in which the resin thin container (a) is filled with liquid and a closing member is attached to the mouth. FIG. 4 is a process diagram for forming the resin sheathing body (b) on the outer surface of the thin resin container (a). FIG. 4 (a) shows the resin thin container (a) set in the mold. FIG. 4 (b) shows a state where the mold is closed, and FIG. 4 (c) shows a resin outer package (b) integrally with the outer surface of the thin resin container (a). It is the figure which showed the state which formed. 5A and 5B are process diagrams until the mold is opened to obtain the composite container (A), in which FIG. 5A shows a state in which the mold is opened, and FIG. 5B shows the inside of the mold. It is the figure which showed the state which takes out a composite container (A) from. FIG. 6 is a perspective view of another embodiment of the composite container (A) manufactured by the manufacturing method of the present invention. FIG. 7 is a perspective view of another embodiment of the composite container (A) manufactured by the manufacturing method of the present invention. FIG. 8 is a bottom view of the composite container (A) manufactured by the manufacturing method in Example 1 (an example in which water at 30 ° C. is fully filled in the thin resin container (a)). FIG. 9 is a bottom view of the composite container (A) manufactured by the manufacturing method in Comparative Example 1 (an example in which 40 ° C. water is fully filled in the thin resin container (a)). FIG. 10 is a composite container (A) manufactured by the manufacturing method in Comparative Example 5 (an example in which 60 ° C. water is fully filled in the resin thin-walled container (a)), and FIG. A bottom view and FIG. 11 (b) are enlarged views of the bottom side of the front view. FIG. 11 is a graph showing the relationship between the liquid filling temperature (° C.) filled in the resin thin container (a) and the capacity reduction rate (%). FIG. 12 is a perspective view of a conventional composite container.

Hereinafter, embodiments (examples) of the present invention will be described in more detail with reference to the drawings.
The “bottle-like form” as used in this specification is a form in which the mouth part and the housing part are connected via a shoulder part, that is, the mouth part narrowed to the upper end of the housing part from the outer shape of the housing part. The form which has this.

FIG. 1 is a perspective view of an embodiment of a composite container (A) manufactured by the manufacturing method of the present invention, and FIG. 2 is a cross-sectional view of an embodiment of the composite container (A) manufactured by the manufacturing method of the present invention. is there.
First, the composite container (A) manufactured by the manufacturing method of this invention is demonstrated.

<Composite container (A)>
The composite container (A) manufactured by the manufacturing method of this invention is used in order to accommodate liquid substances, such as a lotion, a chemical | medical agent, and a drink.

  As shown in FIGS. 1 and 2, the composite container (A) includes a resin thin container (a) having a mouth portion 14 for taking in and out a liquid material, and an outer surface of the resin thin container (a). A resin sheathing body (b) formed so as to cover completely and a capping member (c) which is attached to the mouth portion 14 of the resin thin-walled container (a) and prevents the liquid material from splashing outward from the mouth portion 14 ) And.

  That is, in the composite container (A), a resin sheathing body (b) in which the molten resin is overmolded on the outer surface of the thin resin container (a) excluding the mouth portion 14 and integrally fused is formed. A plug member (c) is attached to the mouth portion 14 of the thin container (a).

  In this embodiment, the mouth portion 14 and the closing member (c) are configured to be screwed together. However, the mounting method is not limited to this, and for example, the closing member (c) is attached to the mouth portion 14. May be configured so that the liquid material is not scattered from the mouth portion 14 of the thin resin container (a).

  In the present embodiment, the thin resin container (a) is a so-called bottle-like form in which the mouth portion 14 and the container portion 12 are continuously formed through the shoulder portion 16, and the thin resin container (a). The thickness T1 is 0.1 to 2.0 mm, preferably 0.5 to 1.5 mm. On the other hand, the resin sheathing body (b) can be formed into various shapes such as the same shape as the resin thin-walled container (a) or a substantially spherical shape as shown in FIGS. Therefore, the thickness T2 of the maximum portion where the thickness is maximum is 3.0 to 50.0 mm, preferably 3.5 to 45.0 mm, and the range is wide, and even a considerable thickness can be formed.

  If the thickness of the resin thin container (a) is considerably reduced, the amount of resin used can be reduced and the manufacturing cost can be reduced. Moreover, since it can make it difficult to see the interface of a resin thin container (a) and a resin exterior body (b), it can be set as the composite container (A) which has the outstanding beauty | look.

  The maximum thickness T2 at which the thickness of the resin sheathing body (b) is maximum can be molded in any manner depending on the thickness, material, molding conditions, etc. of the resin thin-walled container (a). The thickness of the resin thin-walled container (a) is preferably 3 to 60 times, and if within that range, the resin thin-walled container (a) is not deformed and has a high-class feeling and heavy feeling. A container (A) can be obtained.

  Such a composite container (A) uses, for example, a highly transparent synthetic resin as a material of the resin outer package (b), and its total light transmittance (measured with a 1 mm thick sheet in accordance with JIS K7105) is 80. It is preferably ˜100%, and more preferably 85˜100%.

  For example, ionomer resin, acrylic resin, polyester resin, styrene resin (styrene / acrylonitrile copolymer resin, styrene / methyl methacrylate copolymer resin, etc.) is used as the material of the highly transparent synthetic resin satisfying the above range. Preferably, an ionomer resin or a polyester resin, more preferably an ionomer resin can be used.

  As the ionomer resin, for example, at least part of the carboxyl group of the ethylene / unsaturated carboxylic acid copolymer having an unsaturated carboxylic acid content of 1 to 40% by weight, usually more than 0 mol% and not more than 100 mol%, preferably What neutralized 90 mol% or less with the metal ion can be used.

  The ethylene / unsaturated carboxylic acid copolymer serving as the base polymer of the ionomer resin is obtained by copolymerizing ethylene, an unsaturated carboxylic acid, and optionally another polar monomer. Examples of the unsaturated carboxylic acid include acrylic acid, methacrylic acid, fumaric acid, maleic acid, maleic anhydride, monomethyl maleate, monoethyl maleate and the like, and methacrylic acid is particularly preferable.

  The polar monomer that can be a copolymerization component is optionally selected from vinyl esters such as vinyl acetate and vinyl propionate, methyl acrylate, ethyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, and n-acrylate. -Unsaturated carboxylic acid esters such as hexyl, isooctyl acrylate, methyl methacrylate, ethyl methacrylate, dimethyl maleate, diethyl maleate, carbon monoxide, etc., especially unsaturated carboxylic acid esters are suitable copolymerization components It is.

Metal ions having monovalent, divalent or trivalent valences, particularly metal ions having 1 to 3 valences of groups IA, IIA, IIIA, IVA and VIII in the periodic table of elements. Specifically, Na ⁺ , K ⁺ , Li ⁺ , Cs ⁺ , Ag ⁺ , Hg ⁺ , Cu ⁺ , Be ⁺⁺ , Mg ⁺⁺ , Ca ⁺⁺ , Sr ⁺⁺ , Ba ⁺⁺ , Cu ⁺⁺ , Cd ⁺⁺ , Hg ⁺⁺ , Sn ⁺⁺ , Pb ⁺⁺ , Fe ⁺⁺ , Co ⁺⁺ , Ni ⁺⁺ , Zn ⁺⁺ , Al ⁺⁺⁺ , Sc ⁺⁺⁺ , Fe ⁺⁺⁺ , Y ⁺⁺⁺ etc. are mentioned.

Among these, more specifically, it is preferable to use an ionomer resin of an ethylene / (meth) acrylic acid copolymer.
These materials are excellent in transparency, impact resistance, and scratch resistance, and can be thickly molded, so that a heavy feeling like glass can be obtained, and the material of the resin outer package (b) It is suitable as.

  Note that any resin material may be used for the thin resin container (a) and the closure member (c). For example, polyolefin resin (polyethylene, polypropylene, etc.), polyester (PET (polyethylene terephthalate), PETG, PCTG, PCT (polycyclohexane, dimethyl, terephthalate), PCTA, PEN (polyethylene, naphthalate, etc.), acrylic resin, styrene resin (styrene, acrylonitrile copolymer resin, styrene / methyl methacrylate copolymer resin, etc.), cyclo Olefin polymer, polycarbonate, polyamide, ionomer resin, and PAN (polyacrylonitride) can be used. By using the same material as the above resin outer package (b), synergistic effect with the resin outer package (b) is possible. It was obtained, and it is possible to further enhance the sense of quality and aesthetics.

  However, for the resin thin container (a), the resin sheathing body (b) is made to flow by flowing molten resin on the outer surface in a state where the resin thin container (a) is set in the mold as will be described later. In order to form, when using highly transparent synthetic resin, it is preferable to use polyester, polyamide, etc. with a relatively high melting temperature.

  Such a highly transparent synthetic resin may be colored or colorless, and the color may be changed by the resin thin container (a), the resin outer package (b), and the closing member (c). it can.

<Method for producing composite container (A)>
Next, the manufacturing method of the composite container (A) demonstrated above is demonstrated.
As shown in FIG. 3A, first, a bottle-shaped resin thin-walled container (a) in which the mouth part 14 and the container part 12 are connected by the shoulder part 16 is prepared. The thin resin container (a) is manufactured in advance by a method such as blow molding or vibration welding, and the manufacturing method is not particularly limited.

  Next, as shown in FIG. 3B, the liquid 20 is caused to flow into the inside through the mouth portion 14 of the thin resin container (a), and the closing member (c) is attached to the mouth portion 14. The liquid 20 is injected when the resin thin container (a) is set in dies 30 and 32, which will be described later, and the molten resin flows into the outer surface of the resin thin container (a). The accommodating portion 12 of the thin resin container (a) is fully filled so that the thin resin container (a) is not deformed by pressure.

  Since such a liquid 20 is heated to some extent in the molds 30 and 32, it is preferable that the liquid 20 has normal physical properties even when heated. For example, water, aqueous solution, lotion, chemicals, organic solvent Can be used.

In particular, water is suitable as the liquid 20 that is fully filled in the resin thin container (a) because the resin thin container (a) can be dried without being washed after the composite container (A) is manufactured.
The temperature of the liquid 20 fully filled in the thin resin container (a) is suitable for cooling the molten resin immediately before overmolding the molten resin on the outer surface of the thin resin container (a) as described later. It is necessary to set the temperature.

The temperature of the liquid 20 is preferably 30 ° C. or less immediately before the molten resin is overmolded on the outer surface of the thin resin container (a).
Here, 30 ° C. or less means that depending on the type of the liquid 20, the liquid may be maintained even at 0 ° C. or less. For example, in the case of water, the temperature is preferably 0 ° C. or more and 30 ° C. or less. More preferably, it is 5 degreeC or more and 30 degrees C or less. If the temperature of the water supplied directly from the water supply is 30 ° C. or lower, it is preferable to use the tap water from the viewpoint of reducing the manufacturing cost without requiring any cooling equipment.

  The temperature of the liquid 20 is preferably as low as possible. However, if it is frozen too low, it takes time to remove the resin 20 from the thin resin container (a). Therefore, it is important to keep the temperature of the liquid 20 low. is there.

  The temperature of the liquid 20 fully filled in the thin resin container (a) is immediately after the liquid thin container (a) is filled with the liquid 20 and the closing member (c) is attached to the mouth 14. When moving to the next overmolding step, the temperature of the liquid 20 filled in the resin thin container (a) should be about 25 ° C. or lower, which is necessary for overmolding the molten resin. At 30 ° C. or less.

  In addition, when the liquid thin container (a) is filled with the liquid 20 and the closing member (c) is attached to the mouth portion 14, the process proceeds to the next step of overmolding after a while. The temperature of the liquid 20 at the time of filling the resin thin-walled container (a) may be set lower, and this temperature can be set as appropriate.

  Next, as shown in FIG. 4A, the resin thin-wall container (a) filled with the liquid 20 prepared in advance in the molds 30 and 32 is attached to the mouth part 14 and the mouth part 14. Only the closing member (c) is fixed, and the portion of the accommodating portion 12 of the resin thin-walled container (a) floats in the space in the molds 30 and 32. At this time, the temperatures of the molds 30 and 32 are preferably set in a range of 5 to 100 ° C.

Further, in this state, the molds 30 and 32 are closed as shown in FIG. 4B, and the molten resin is filled into the molds 30 and 32 from the resin inlet 34 as shown in FIG. The molten resin to be filled has an injection pressure of 100 to 2000 kg / cm ² and a temperature of 100 to 350 ° C.

Immediately before the molten resin is filled, the liquid 20 inside the resin thin-walled container (a) is 30 ° C. or lower.
As described above, when the liquid 20 is 30 ° C. or lower, the molten resin filled in the molds 30 and 32 is quickly cooled and fused integrally to the outer surface of the thin resin container (a). Thus, the composite container (A) having a good appearance, a beautiful appearance, and a high-class feeling can be obtained without causing variations in the volume and outer shape of the housing portion 12.

  On the contrary, when the liquid 20 is higher than 30 ° C., the molten resin filled in the molds 30 and 32 becomes difficult to be cooled, and the resin thin container (a) is deformed by the heat of the molten resin. Therefore, the temperature of the liquid 20 in the thin resin container (a) immediately before the molten resin is filled in the molds 30 and 32 is important.

  In this way, the molten resin is overmolded from the lower end of the mouth portion 14 of the resin thin container (a) in the molds 30 and 32 to the outer surface of the resin thin container (a), and the resin thin container (a ) And the resin outer package (b) part fused together.

  Then, the molds 30 and 32 are opened as shown in FIG. 5 (a), and the composite container (A) is taken out from the molds 30 and 32 as shown in FIG. 5 (b), and the runner and sprue are removed. Then, the plug member (c) attached to the mouth portion 14 is removed, and the liquid 20 filled in the resin thin-walled container (a) is removed.

  Then, the inside of the container 12 of the thin resin container (a) may be cleaned in some cases and then dried, and the plug 14 is attached to the mouth portion 14 again, as shown in FIG. The manufacture of the composite container (A) in which the resin sheathing body (b) is integrally fused to the outer surface excluding the mouth portion 14 of the container (a) is completed. When the liquid 20 is water, it is not necessary to clean the inside of the accommodating portion 12 of the resin thin-walled container (a), and only drying is required, which can contribute to productivity improvement.

  The composite container (A) manufactured by such a manufacturing method is excellent in that the appearance and the appearance of the resin thin-walled container (a) are excellent in appearance, without causing variations in the volume and outer shape of the container. It has a beautiful appearance and luxury.

  Further, since the outer surface of the resin thin container (a) and the resin outer package (b) are integrally fused, the resin thin container (a) is placed inside the resin outer package (b). It does not rattle or rotate, and the boundary line between both members is difficult to see.

  Furthermore, since the resin thin container (a) is made of resin and the resin outer package (b) is made of a highly transparent synthetic resin, it is excellent in recyclability, and the resin thin container (a) inside the resin outer package (b) can be removed. Visible.

Therefore, the composite container (A) obtained by this production method is suitable as a cosmetic container for which stability of storage capacity and aesthetics are desired.
The preferred embodiment of the present invention has been described above, but the present invention is not limited to this. For example, the form of the composite container (A) obtained by the production method of the present invention is also shown in FIG. In short, as long as the resin thin-walled container (a) located in the inner layer is in the form of a bottle, such as a crystal-like form or a form having an uneven portion 40 shown in FIG. Various modifications can be made without departing from the scope of the invention.

[Example 1]
As shown in FIG. 3 (a), the mouth portion 14 and the accommodating portion 12 are so-called bottle-like forms formed continuously through the shoulder portion 16, and have a thickness T1 of 0.8 mm and a polyester. A resin thin container (a) made of resin is prepared, and as shown in FIG. 3 (b), the resin thin container (a) is fully filled with water at 20 ° C., and in this state, the resin thin container A closing member (c) made of polyester resin was attached to the mouth portion 14 of (a).

Then, as shown in FIG. 4 (a), the resin thin-walled container (a) is immediately set in the molds 30 and 32 heated to 25 ° C., and as shown in FIG. 4 (b). 30 and 32 are closed, and as shown in FIG. 4 (c), a molten resin of an ionomer resin of ethylene / (meth) acrylic acid copolymer is applied to the outer surface excluding the mouth portion 14 of the thin resin container (a). Overmolded. The injection pressure of the molten resin applied to the outer surface of the thin resin container (a) set in the molds 30 and 32 at this time was 600 kg / cm ² and the holding pressure was 480 kg / cm ² . As other molding conditions, the resin temperature was 182 ° C., the injection speed was 15 mm / s, the injection time was 34 s, and the cooling time was 40 s.

  Then, after forming the resin outer package (b) having a maximum thickness T2 of 15 mm where the molten resin is solidified and having the maximum thickness, the molds 30 and 32 are opened as shown in FIG. The composite container (A) was obtained by removing the runner and sprue from the molded product as shown in FIG.

  In the obtained composite container (A), when the capacity of the container 12 of the thin resin container (a) before overmolding is 100%, the average decrease rate of the capacity after molding is 0.29% (Table 1). ) And very little, almost no change in shape, and the appearance was good (FIG. 8).

[Example 2]
A composite container (A) was obtained in the same manner as in Example 1 except that the resin thin-walled container (a) was fully filled with 30 ° C. water.

  The obtained composite container (A) has an average reduction rate of the capacity after molding of 0.50% when the capacity of the container 12 of the resin thin-wall container (a) before overmolding is 100% (Table 1). ) And little, almost no change in shape and good appearance.

[Comparative Examples 1-5]
A composite container (A) is obtained in the same manner as in Example 1 except that the resin thin-walled container (a) is fully filled with water at 40 ° C., 45 ° C., 50 ° C., 55 ° C., and 60 ° C. It was.

  In the obtained composite container (A), when the capacity of the container 12 of the thin resin container (a) before overmolding is 100%, the average reduction rate of the capacity after molding is as shown in Table 1. It was.

Further, the bottom surface of the thin resin container (a) is slightly deformed at 40 ° C. (FIG. 9), and is largely crushed at 60 ° C. (FIGS. 10A and 10B). ) Was confirmed.
When the resin thin-walled container (a) is filled with water at 30 ° C. or lower as in Examples 1 and 2 described above, the resin thin-walled container (b) can be overmolded immediately after this. It was confirmed that the container (a) hardly deformed, and the capacity change was small as apparent from the graph shown in FIG.

  On the other hand, as in Comparative Examples 1 to 5, when the resin thin container (a) is filled with water having a temperature higher than 30 ° C., the overmolding of the resin outer package (b) portion performed immediately after this is performed. Thus, it was confirmed that the thin resin container (a) was deformed and the capacity reduction rate was increased as apparent from the graph shown in FIG.

  Therefore, the necessity that the temperature of the liquid with which the resin thin container (a) was filled was 30 degrees C or less immediately before inject | pouring molten resin in the metal mold | die 30 and 32 has been confirmed.

[Example 3]
Using a low-density polyethylene container having a thickness T1 of 0.8 mm as the thin resin container (a), injection pressure is 500 kg / cm ² , holding pressure is 440 kg / cm ² , resin temperature is 185 ° C., injection speed Was 15 mm / s, the injection time was 25 s, and the cooling time was 45 s, a composite container (A) was obtained in the same manner as in Example 1 described above.

  The obtained composite container (A) has an average reduction rate of the capacity after molding as small as 0.5% when the capacity of the accommodating portion 12 of the resin thin-wall container (a) before overmolding is 100%. There was almost no change in shape and the appearance was good.

[Example 4]
A composite container (A) was obtained in the same manner as in Example 3 except that the resin thin container (a) was fully filled with 30 ° C. water.

  The obtained composite container (A) has a small average reduction rate of 1.2% after molding when the capacity of the accommodating part 12 of the resin thin-walled container (a) before overmolding is 100%. There was almost no change in shape and the appearance was good.

[Comparative Example 6]
A composite container (A) was obtained in the same manner as in Example 3 except that the resin thin-walled container (a) was fully filled with 40 ° C. water.

  The obtained composite container (A) has an average reduction rate of the capacity after molding of 7% when the capacity of the container 12 of the resin thin container (a) before overmolding is 100%, and the resin thin wall It was confirmed that the bottom surface of the container (a) was crushed.

[Comparative Example 7]
A composite container (A) was obtained in the same manner as in Example 3 except that the resin thin container (a) was fully filled with 60 ° C. water.

  The obtained composite container (A) has an average reduction rate of the capacity after molding of 20% when the capacity of the container 12 of the resin thin container (a) before overmolding is 100%. It was confirmed that the bottom of the container (a) was greatly crushed.

  When the resin thin-walled container (a) is filled with water at 30 ° C. or lower as in Examples 3 and 4 described above, the resin thin-walled container (b) can be overmolded immediately after this. It was confirmed that the container (a) hardly deformed and the capacity change was small.

  On the other hand, when the resin thin container (a) is filled with water having a temperature higher than 30 ° C. as in Comparative Examples 6 and 7, the overmolding of the resin sheathing body (b) portion performed immediately after this is performed. Thus, it was confirmed that the thin resin container (a) was deformed and the capacity reduction rate was increased.

  Therefore, the necessity that the temperature of the liquid with which the resin thin container (a) was filled was 30 degrees C or less immediately before inject | pouring molten resin in the metal mold | die 30 and 32 has been confirmed.

A ... Composite container a ... Resin thin container b ... Resin sheathing body c ... Closing member 12 ... Housing part 14 ... Mouth part 16 ... Shoulder part 20 ... Liquid 30 ... Mold 32 ... Mold 34 ... Resin inlet 40 ... Concavity and convexity T1 .. Thickness of resin thin container T2 .. Maximum part where thickness of resin outer casing is maximum Thickness 100 ... composite container 102 ... container 104 ... exterior body

Claims (9)

A bottle-shaped resin thin-walled container (a) having a mouth part and a container for containing a liquid substance, and the resin thin-walled container (a) on the outer surface of the resin thin-walled container (a) Manufacture of a composite container (A) comprising a resin outer package (b) integrally fused and a closure member (c) attached to the mouth of the resin thin container (a) A method,
The method for producing the composite container (A) is as follows:
Preparing a bottle-shaped resin thin-wall container (a) and a closure member (c) to be attached to the mouth of the resin thin-wall container (a) in advance;
Filling the entire thin resin container (a) with liquid, and mounting the closure member (c) on the mouth in this state;
Setting the bottle-shaped resin thin-walled container (a) filled with the liquid in a mold;
A molten resin is injected into a mold in which the resin thin container (a) is set, and a resin outer package (b) is integrally fused to the outer surface of the resin thin container (a). Process,
Opening the mold and removing the molded composite container (A);
Having at least
In the step of forming the resin sheathing body (b),
The method for producing a composite container (A), wherein the temperature of the liquid filled in the thin resin container (a) is 30 ° C. or less immediately before injecting the molten resin into the mold. In the step of forming the resin sheathing body (b),
The temperature of the said metal mold | die is set in the range of 5-100 degreeC, The manufacturing method of the composite container (A) of Claim 1 characterized by the above-mentioned. In the step of forming the resin sheathing body (b),
Injection pressure of the molten resin injected into the mold, the production method of the composite container (A) according to claim 1 or 2, characterized in that it is set in the range of 100 to 2,000 kg / cm ² . In the step of forming the resin sheathing body (b),
The resin temperature of the molten resin injected into the mold is set within a range of 100 to 350 ° C, and the composite container (A) according to any one of claims 1 to 3 is manufactured. Method.   The method for producing a composite container (A) according to any one of claims 1 to 4, wherein a thickness of the resin thin container (a) is in a range of 0.1 to 2.0 mm.   The composite container (1) according to any one of claims 1 to 5, wherein the thickness of the maximum portion where the thickness of the resin sheathing body (b) is maximum is within a range of 3.0 to 50.0 mm. A) production method.   The liquid filled in the resin thin-walled container (a) is one selected from water, an aqueous solution, a lotion, a chemical, and an organic solvent. The manufacturing method of the composite container (A) of description. In the step of forming the resin sheathing body (b),
8. The composite container (A) according to claim 1, wherein the molten resin injected into the mold is an ionomer resin of ethylene / (meth) acrylic acid copolymer. Method.   The composite container (A) according to any one of claims 1 to 8, wherein the resin constituting the thin resin container (a) is at least one selected from polyester, polyamide and polyolefin resin. ) Manufacturing method.