JPH09301334A - Composite barrier container - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress the plastic consumption amount of a container as much as possible, prevent the keeping quality of foods and medicines from decreasing, and enable the volume reduction at the time of disposal without losing the easiness in pouring at the time of usage by a method wherein an exterior material for which a barrier layer is inserted is fitted by integrating on the total periphery of the surface of the body part with a thinner thickness of a blow container. SOLUTION: On a raw material 3 which is the same as a blow internal container 2, an inorganic deposited layer 4 is applied, and in addition, a coating layer 5 is superposed for a barrier layer inserted film 1. Then, the barrier layer inserted film 1 is formed into a cylindrical shape and flattened, and is laid under that state, in a blow die, and the film 1 is opened into a cylindrical shape by a suction means in the blow die, and is made to tightly join to the surface of the blow die to blow-mold the internal container 2. By doing so, a composite container for which the internal container 2 and the film 1 are integrated, is formed. By this method, a high barrier property can be obtained by a single raw material which includes the inorganic deposited layer 4 as an intermediate layer, and at the same time, the body part of the internal container 2, is thinner compared with the shoulder part and the low part, and a plastic as a resource can be saved, and the recycling becomes possible.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composite container provided with an inner container made of plastic and an outer packaging material made of a film having a barrier property integrated so as to cover the entire circumference of the body of the inner container. In particular, it is a composite barrier container having excellent gas barrier properties including carbon dioxide gas, water vapor barrier properties, and disposal property.

[0002]

2. Description of the Related Art In general, glass bottles have been used for long-term storage of foods and pharmaceuticals because of their preservability.
In recent years, plastic containers have come to be widely used due to suitability for logistics and ease of use. However, shelf life of 3 to 5 years is required for foods and pharmaceuticals that need to be stored for a long period of time. Therefore, usually, increase the thickness of the entire blow container (0.3
mm to 1 mm) has met the requirements. However, plastic containers are basically one-way,
Used food containers are increasing as garbage every year. However, in the case of landfill disposal, the landfill disposal site is full, and in the case of incineration disposal, there are problems such as damage to the incinerator, which is becoming a problem in terms of global environmental protection. Further, in recent years, containers using biodegradable plastics are expected, but they have not been put into practical use because of high cost and safety problems in food and pharmaceutical applications. Therefore, the emergence of a high barrier thin-walled container was awaited. In addition, although pharmaceutical containers are effective in preventing nosocomial infections, the necessity of environmental measures in recent years makes it difficult to treat the containers after use, especially in large hospitals. At present, it is currently treated as medical waste for a fee. Further, a blow container of a single layer of a polyolefin resin or a polyester resin is widely used for food and beverage, toiletry products, and pharmaceuticals, but it is insufficient as a container for which high barrier property is required. Therefore, multi-layer blow containers have emerged for those requiring a high barrier, but they cannot be reused because they are composite materials.

Beverages containing carbonic acid, such as beer, are conventionally sold in glass bottles and metal cans. These containers have advantages such as excellent oxygen barrier properties and carbon dioxide gas barrier properties, excellent pressure resistance, and little adsorption of contents, but after use they are generally discarded. There is a problem that it cannot be processed as a thing. Although the glass bottle can be used repeatedly, it has a disadvantage that it may be damaged by being dropped or the like and that it is heavy and it is difficult to purchase a large amount of products at once. In addition, metal cans such as steel cans and aluminum cans are not damaged by being dropped or the like, are light in weight, have high usage rates in vending machines, and are becoming more popular. After using this metal can, it is partially recycled as separated waste, but its recovery rate is still low. In addition, since it is easy to use, it has been used and discarded in large quantities in tourist spots, tourist resorts, etc., and its collection and disposal has become a major social problem.

Further, in addition to the glass bottle and the metal can, a hollow container made of polyethylene terephthalate (hereinafter abbreviated as PET) is used as a container for beverages, alcoholic beverages, seasonings and the like because of its transparency, light weight and safety. For versatile use,
On the market. The PET container has the advantages described above, but has an oxygen barrier property compared to glass bottles and metal cans.
Since carbon dioxide gas barrier property, water vapor barrier property, etc. are inferior,
Color tone changes such as decolorization and discoloration of the contents occur, or the contents are altered. In particular, as a container for carbonated drinks, there is a risk that carbon dioxide gas in the content liquid may escape, so that the container was not suitable for long-term storage. Therefore, in order to compensate for the poor gas barrier property of the PET container, a resin structure in which a material excellent in gas barrier property, for example, a polyamide resin, a saponified product of ethylene-vinyl acetate copolymer (hereinafter abbreviated as EVOH) is laminated. Are known. This container having a laminated structure is difficult to recycle after the contents are used and cannot be separated according to the type of resin, which has become a big problem in recent years. As described above, currently popular plastic containers do not satisfy both storage suitability of contents and recyclability after use, and various improvements are required.

[0005]

Therefore, in view of the above problems, the present invention has an oxygen barrier property, a carbon dioxide gas barrier property,
It satisfies gas barrier properties such as water vapor barrier properties, and can separate plastics after use, making disposal such as recycling simpler and maintaining a high barrier property while minimizing the amount of plastic used in containers. Hold down,
It is an object of the present invention to provide a composite container that does not deteriorate the storability of foods and pharmaceuticals, does not lose the ease of pouring during use, and satisfies the volume reduction at the time of disposal.

[0006]

The present invention has been conceived in order to solve the above-mentioned problems. According to the invention of claim 1, at least one of the body, shoulder and bottom has a different wall thickness. Is a composite barrier container in which an outer packaging material having a barrier layer is integrally formed on the entire circumference of the surface of the thin portion of the blow container which is thinner than the wall thickness. The invention according to claim 2 is the composite barrier container according to claim 1, wherein the thickness of the body portion of the blow container is smaller than the thicknesses of the shoulder portion and the bottom portion. The invention according to claim 3 is the composite barrier container according to claim 1, wherein the thickness of the body and shoulder of the blow container is smaller than the thickness of the bottom of the bottom. The invention according to claim 4 is the composite barrier container according to claim 1, characterized in that any of the body, shoulder and bottom of the blow container is thin. The invention according to claim 5 is characterized in that the exterior material having a barrier layer interposed is a plastic film having a thin film layer of an inorganic compound provided on the surface thereof. It is a barrier container. In the invention according to claim 6, the exterior material in which the barrier layer is interposed is
The composite barrier container according to any one of claims 1 to 4, wherein a metal oxide thin film layer is provided on the surface of the plastic film. The invention according to claim 7 is characterized in that the exterior material having a barrier layer interposed therebetween has a thin film layer of an inorganic oxide provided on the surface of a plastic film, and the composite barrier container according to any one of claims 1 to 4. Is. The invention according to claim 8 is the composite barrier container according to any one of claims 5 to 7, characterized in that the thin film layer on the surface of the plastic film is provided by vapor deposition. The invention according to claim 9 is the composite barrier container according to claim 8, wherein the thin film layer on the surface of the plastic film is a glass vapor deposition layer. The invention according to claim 10 is characterized in that the exterior material with the barrier layer interposed is based on a plastic film different from the material of the blow container as a base material, and the composite barrier container according to any one of claims 1 to 9. Is. The invention according to claim 11 is the composite barrier container according to any one of claims 1 to 4, characterized in that the exterior material having the barrier layer interposed therein includes a barrier film. The invention according to claim 12 is the composite barrier container according to any one of claims 1 to 4, wherein the exterior material having the barrier layer interposed therebetween includes a film provided with a coating layer of a barrier resin. is there. The invention according to claim 13 is characterized in that the exterior material with the barrier layer interposed is based on a plastic film of the same type as the material of the blow container, as a base material, and the composite barrier container according to any one of claims 1 to 9. Is. The invention according to claim 14 is the composite barrier container according to any one of claims 1 to 13, wherein the exterior material having the barrier layer interposed therein contains paper.
A fifteenth aspect of the present invention is the composite barrier container according to any one of the first to fourteenth aspects, wherein the blow container and the exterior material with the barrier layer interposed are separable from each other. The invention according to claim 16 is characterized in that an adhesive having an adhesive effect at the molding temperature of the blow container is provided on the inner surface of the exterior material with the barrier layer interposed therebetween. This is a composite barrier container. The invention according to claim 17 is the composite barrier container according to claim 16, wherein the adhesive is an ethylene vinyl acetate-based adhesive and the coating amount is 3 g / m ² or less.

[0007]

Next, the present invention will be described specifically. First, the material of the blow container which is the inner container of the composite container according to the present invention may be a moldable thermoplastic resin such as blow molding and stretch blow molding, and examples thereof include polyethylene terephthalate (PET) and polyacrylonitrile (P
AN), polyethylene naphthalate (PEN), polypropylene (PP), polyethylene (PE), ethylene-
Polyolefin resin such as vinyl alcohol copolymer (EVOH), polyamide resin (PA), polyester resin and the like can be used. Further, a laminated material of these resins can be used as a material for the inner container, but a single layer material is preferable in consideration of recycling after disposal. The substrate 3 of the film 1 with the barrier layer interposed is a film or sheet mainly made of plastic, and is made of polyolefin (PE, PP, etc.), polyester (PET, PEN, P).
BT, etc., Polyamide (Nylon-6, Nylon-66)
Etc.), polyvinyl chloride (PVC), polyimide, etc., or copolymers of these polymers, etc., which are usually used as packaging materials can be used. The thickness of the base material 3 can be in the range of 1 μm to 1 mm and may be within this range if only the gas barrier property of the container is improved, but if the rigidity of the container is taken into consideration, the thickness of the inner container is 1 A thickness of / 2 or more is preferable. Further, for example, additives such as an antistatic agent, an ultraviolet absorber, a plasticizer, a lubricant and a colorant can be added to the base material 3 as required. Furthermore, the surface of the base material 3 can be modified by corona treatment, anchor coat treatment, or the like to improve the adhesion with the inorganic vapor deposition layer. And as an example of the structure of the exterior material 1 with the barrier layer interposed,
As shown in FIG. 1, substrate 3 / inorganic vapor deposition layer 4 / covering layer 5
Can be used. In addition, as a configuration of the exterior material 1 with the barrier layer interposed, for example, paper (not shown) may be laminated on the inner side (innermost layer) of the base material 3.

The inorganic vapor deposition layer 4 is made of a metal such as silicon, aluminum, magnesium, titanium, zirconium, an oxide of an inorganic substance, a nitride, a simple substance of fluoride, or a combination thereof, and is vacuum vapor deposition method, sputtering method, plasma. Although it is formed by a vacuum process such as a vapor phase growth method, silicon oxide is preferable in consideration of transparency. The film thickness of the inorganic vapor deposition layer 4 varies depending on the use and the film thickness of the coating layer 5, but a range of several tens of Å to 5,000 Å can be used, but if it is less than 50 Å, it is insufficient in terms of the continuity of the film. If it exceeds the range, cracks are likely to occur and the flexibility is lowered. Therefore, the range is preferably 50 Å to 3000 Å.

The inorganic vapor deposition layer 4 may be formed on any layer of the film 1 with a barrier layer interposed, but the material of the base material 3 is PE, PP or the like, oxygen barrier property, carbon dioxide gas barrier property or the like gas. When using a plastic film having a poor barrier property, or when the film is thick, it is better to form the innermost layer in contact with the blow container, which is the plastic inner container 2, from the viewpoint of improving the gas barrier property. preferable. The coating layer 5 may be omitted, but when the vapor deposition layer is the outer surface of the container, it is preferable from the viewpoint of protecting the inorganic vapor deposition layer 4, such as polyvinyl alcohol (PVA), starch, methyl cellulose, carboxymethyl cellulose, and the like. A water-soluble polymer is used as a coating agent, and the coating agent may contain a metal alkoxide and its hydrolyzate, tin chloride or the like. Further, as the coating layer 5, PE, PP, PET, PV
It is also possible to use a film such as C stuck together.

The coating agent can be applied by dipping method, roll coating method, screen printing method,
Means such as a spray method is used. The thickness of the coating varies depending on the type of coating agent, but is 0.01 μm-100
The thickness may be in the range of μm, and if it exceeds 50 μm, cracks are likely to occur in the film, so 0.01 to 50 μm is desirable. Further, the film 1 having a barrier layer interposed may have a structure using a barrier film not provided with the inorganic vapor deposition layer 4. Examples of such a barrier film include a saponified ethylene-vinyl acetate copolymer, Single layer of polyamide resin, nitrile resin, polyvinylidene chloride resin, cyclic polyolefin resin, etc.,
Alternatively, a multilayer film or a film having a surface coated with these resins can be used.

In addition, it is desirable to use a degradable polymer as the plastic material of the film with the interposition of the blow container and the barrier layer in order to make disposal after use easier. As the degradable polymer, it is desirable to use a microbial degradable polymer that can be decomposed as it is by burying it in soil after using polylactic acid type, aliphatic polyester type hydroxypolyester type or the like.

As an example of the method for producing a container of the present invention, a blow metal is formed in a state in which a film 1 having a barrier layer formed by depositing a glass (SiO) vapor-deposited layer on the same material as the material of the blow container is formed into a cylindrical shape and is flat. The blow container and the film 1 are placed in a mold, and the film 1 is opened into a cylindrical shape by suction means (not shown) mounted in the blow mold and brought into close contact with the surface of the blow mold to perform blow molding. An integrated composite container is molded, and a high barrier can be achieved with a single material in which the glass vapor deposition layer serves as an intermediate layer. In this case, as shown in FIG. 2, the body portion 6 is thinner than the shoulder portion 7 and the bottom portion 8. This saves plastic as a resource and allows reuse. At this time, an adhesive layer is required on the glass vapor deposition surface, and an ethylene-vinyl acetate copolymer (EVA) adhesive can be used. Since it is difficult to integrate the film having the barrier layer between the shoulder and the bottom of the blow container, the wall thickness is maintained at about 0.2 mm to 1 mm. In addition, high-density polyethylene (HDPE) and polypropylene (CP
Resins such as P), vinyl chloride and nylon can be used. Of course, when molding the blow container, the direct blow method as described above may be used, but a method in which a preformed body (preform) is injection-molded in advance and then heated to be blow-molded may be used. In that case, it is desirable to use an adhesive of a type that exhibits an adhesive effect at the molding temperature of the preform. Furthermore, an alkaline solution as an adhesive,
If you choose one that dissolves easily in warm water, you can control the adhesive strength between the blow container and the film with the barrier layer in between,
After the container is used, the blow container and the film with the barrier layer interposed therebetween can be easily separated, and the disposal process becomes simple.

With the above construction, the composite container of the present invention can realize volume reduction at the time of disposal without impairing ease of use and barrier properties. Also, the amount of waste plastic can be reduced. Further, when the blow container and the film with the barrier layer interposed are made of the same material, they can be reused, and there is no need to separate the film with the blow container and the barrier layer interposed therebetween, which facilitates disposal, and also It can greatly contribute to the conservation of the global environment. In addition, PE is used as the material for the blow container.
If N and PAN are used, the oxygen barrier property, the carbon dioxide gas barrier property, and the water vapor barrier property are particularly excellent, and at least the thin body of the blow container is integrated with the film with the barrier layer interposed. Thereby, the barrier property can be enhanced and the shelf life of the contents can be lengthened.

[0014]

Embodiments of the present invention will be described below. <Example 1> 0.1 mm thick high-density polyethylene (H
DPE) is laminated, 300 Å thick silicon oxide is vapor-deposited, a polyolefin adhesive is applied to the silicon oxide surface of the exterior material, and it is placed in a mold, in which HDPE is directly blow molded. The average container thickness 0.25 mm, the body average wall thickness 0.15 mm, and the bottom average wall thickness 0.25 mm shown in FIG. The oxygen and water vapor barrier properties and wall thickness of the molded products were measured to test whether the container could be crushed. The above results are shown in Table 1. <Example 2> A preform molded by injection molding using PET (intrinsic viscosity 0.7 g / dl) was heated by an infrared heater, and coated paper 320 g / m ² with a thickness of 0.1 m.
m PET film is laminated and a 400 Å-thick silicon oxide film is vapor-deposited on the opposite side of the vapor-deposited surface of the exterior material to apply a coating amount of 3 g / m
² EVA adhesive is applied, placed in a mold, stretch blow molded therein, and the average shoulder thickness shown in FIG. 3 is 0.15
mm, body average wall thickness 0.15 mm, bottom average wall thickness 0.1
A composite container having an inner volume of 5 mm and an inner volume of 500 ml was molded. Example 3 A multi-layer film of polyethylene having a thickness of 0.1 mm and a saponified product of ethylene-vinyl acetate copolymer (EVOH) is attached, and a polyolefin (P
O) -based adhesive was applied at a coating amount of 5 g / m ² and the shaped film was used in the same manner as in Example 5 to measure the shoulder average wall thickness shown in FIG. Average wall thickness 0.15m
m, a bottom part average wall thickness of 0.15 mm, and an inner volume of 500 ml. <Example 4> A preform molded by injection molding using PEN (intrinsic viscosity: 0.6 g / dl) was heated by an infrared heater, and a 12 μm-thick PET film was prepared in advance, and an aluminum vapor deposition layer having a thickness of 80 Å was formed on the surface. A film comprising the heat-sensitive adhesive layer is placed in a mold and stretch blow-molded therein, and the average thickness of the shoulder portion shown in FIG. 4 is 0.18 m.
m, average body thickness of 0.17 mm, average bottom thickness of 0.20
A composite container having a mm content of 500 ml was molded. <Example 5> The preformed body of Example 2 was EVO
H: PET = 5: 95 (weight ratio) except that the blend resin was changed to the same average shoulder thickness of 0.15 shown in FIG.
mm, body average wall thickness 0.15 mm, bottom average wall thickness 0.1
A composite container having an inner volume of 5 mm and an inner volume of 500 ml was molded. <Example 6> 320 g / m ^{2 of} coated paper with a thickness of 0.1 mm
PET film is laminated, and the exterior material coated with a silicon oxide film with a thickness of 400Å is placed in the mold so that the coated paper faces the mold, and polypropylene (MI = 0.5) is blow molded to obtain a wall thickness of 0.
A composite container having an inner volume of 2 mm and a volume of 500 ml was molded.

<Comparative Example 1> The average thickness of the shoulder portion was 0.
An HDPE blow container having an inner volume of 50 mm, an average wall thickness of the body of 0.45 mm, and an average wall thickness of the bottom of 0.50 mm and an inner volume of 500 ml was molded. The evaluation was performed in the same manner as in Example 1 and is shown in Table 1. <Comparative Example 2> In the same manner as in Example 4 except that the film with the barrier layer interposed was not used, the average thickness of the shoulder portion was 0.25 mm, the average thickness of the body portion was 0.15 mm, and the average thickness of the bottom portion was 0.25 mm. An HDPE blow container having an inner volume of 500 ml was molded. Evaluation is performed in the same manner as in Example 1 and Table 1
It was shown to. <Comparative Example 3> In the same manner as in Example 5 except that the film with the barrier layer interposed was not used, the average thickness of the shoulder portion was 0.25 mm, the average thickness of the body portion was 0.15 mm, and the average thickness of the bottom portion was 0.25 mm. A PET container having an inner volume of 500 ml was molded. <Comparative Example 4> In the same manner as in Example 4, except that the film having the barrier layer interposed was not used, the average thickness of the shoulder portion was 0.18 mm, the average thickness of the body portion was 0.17 mm, and the average thickness of the bottom portion was 0.38 mm. A PEN container having an inner volume of 500 ml was molded. <Comparative Example 5> In the same manner as in Example 6 except that the film with the barrier layer interposed was not used, the average thickness of the shoulder portion was 0.25 mm, the average thickness of the body portion was 0.15 mm, and the average thickness of the bottom portion was 0.25 mm. EVOH / PE with a capacity of 1000 ml
A T-blend container was molded. Comparative Example 6 A PP single-layer container having an inner volume of 1500 ml and a wall thickness of 0.2 mm was molded in the same manner except that the film having the barrier layer interposed in Example 6 was not used. Table 1 shows the measurement results and evaluation results for the oxygen permeability, the water vapor permeability, the body wall thickness, and the volume reduction at the time of disposal of Example 1 and Comparative Examples 1 and 2, respectively.
Table 2 summarizes the measurement results of oxygen permeability and water vapor permeability of Example 6 and Comparative Examples 3 to 6.

[0016]

[Table 1]

[0017]

[Table 2]

[0018]

EFFECTS OF THE INVENTION By using the container of the present invention, the water vapor barrier property and the oxygen barrier property are not inferior to conventional multi-layered barrier property blow containers, and the wall thickness can be reduced, and the container can be crushed at the time of disposal. Will be easier. Further, if the material of the blow container is selected, the carbon dioxide gas barrier property can also be satisfied. In addition, since the glass vapor-deposited layer other than the adhesive can be reused, it is possible to provide a packaging container that does not adversely affect the environment. Further, since the amount of resin used can be reduced, the calories burned can be reduced even when incinerated, and the incinerator is not damaged.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional view showing an example of an exterior material with a barrier layer interposed according to the present invention.

FIG. 2 is an explanatory view showing an example of a composite container according to the present invention.

FIG. 3 is an explanatory view showing another example of the container of the present invention.

FIG. 4 is an explanatory view showing still another example of the container of the present invention.

[Explanation of symbols]

 1: Exterior material 2: Inner container 3: Base material 4: Inorganic substance vapor deposition layer 5: Coating layer

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Katsuyuki Ohno 1-5-1 Taito, Taito-ku, Tokyo Within Toppan Printing Co., Ltd. (72) Inventor Takekuni Seki 1-5-1 Taito, Taito-ku, Tokyo Toppan Imprint Co., Ltd. (72) Inventor Keiko Nakamura 1-5-1 Taito, Taito-ku, Tokyo Tokyo Toppan Imprint Co., Ltd.

Claims (17)

[Claims] 1. A barrier layer is provided on the entire circumference of the surface of the thin portion of the blow container in which the wall thickness of at least one of the body portion, the shoulder portion and the bottom portion is smaller than that of other portions. A composite barrier container that integrates exterior materials. 2. The composite barrier container according to claim 1, wherein the thickness of the body of the blow container is thinner than the thickness of the shoulder and bottom. 3. The composite barrier container according to claim 1, wherein the thickness of the body and shoulder of the blow container is thinner than the thickness of the bottom of the bottom. 4. The composite barrier container according to claim 1, wherein each of the body, shoulder and bottom of the blow container is thin. 5. The composite barrier container according to any one of claims 1 to 4, wherein the exterior material having the barrier layer interposed is a plastic film surface provided with a thin film layer of an inorganic compound. 6. The composite barrier container according to any one of claims 1 to 4, wherein the exterior material having the barrier layer interposed is a plastic film having a metal oxide thin film layer provided on the surface thereof. . 7. The composite barrier container according to claim 1, wherein the exterior material having the barrier layer interposed is a plastic film having a thin film layer of an inorganic oxide provided on the surface thereof. 8. The thin film layer on the surface of the plastic film is provided by vapor deposition.
8. The composite barrier container according to claim 7. 9. The composite barrier container according to claim 8, wherein the thin film layer on the surface of the plastic film is a glass vapor deposition layer. 10. The composite barrier container according to any one of claims 1 to 9, wherein the exterior material having the barrier layer interposed therebetween is based on a plastic film different from the material of the blow container. 11. The composite barrier container according to any one of claims 1 to 4, wherein the exterior material having the barrier layer interposed therein is configured to include a barrier film. 12. The composite barrier container according to claim 1, wherein the exterior material having the barrier layer interposed therebetween includes a film provided with a coating layer of a barrier resin. 13. The composite barrier container according to any one of claims 1 to 9, wherein the exterior material with the barrier layer interposed is made of a plastic film of the same kind as that of the blow container material. 14. The composite barrier container according to claim 1, wherein the exterior material having the barrier layer interposed therein contains paper. 15. The composite barrier container according to claim 1, wherein the blow container and the exterior material having the barrier layer interposed therebetween are separable from each other. 16. An inner surface of an exterior material having a barrier layer interposed,
The composite barrier container according to any one of claims 1 to 15, further comprising an adhesive that exhibits an adhesive effect at a molding temperature of the blow container. 17. The composite barrier container according to claim 16, wherein the adhesive is ethylene vinyl acetate based and the coating amount is 3 g / m ² or less.