Hollow molded containers and bag-in-boxes

Abstract

The present invention provides a hollow molded container that uses recycled materials while maintaining stable physical properties. It also provides a bag-in-box container that incorporates such a hollow molded container as an inner bag. [Solution] A hollow molded container comprising a container body having an internal space for storing contents, and a mouth member provided on the container body, wherein the container body is a molded body of a laminated film made of thermoplastic resin, and the laminated film has a first layer made of virgin thermoplastic resin as the forming material and a second layer made of recycled thermoplastic resin as the forming material.

Description

Technical Field

[0001] The present invention relates to a hollow molded container and a bag-in-box.

Background Art

[0002] In recent years, double containers, in which a foldable packaging bag (inner bag) made of a plastic film is housed inside a paper outer box and which are mainly used for liquid filling, have been widely used for commercial or household purposes (see Patent Document 1). This type of double container is called a bag-in-box.

[0003] The bag-in-box compensates for the disadvantages of packaging bags made of plastic film, namely fragility and irregular shape, by using a paper outer box. In addition, the bag-in-box has an excellent function that after the filled contents are consumed, both the inner bag and the outer box can be folded, so that the overall volume can be reduced.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In recent years, attention to environmental issues has been increasing, and resin products with low environmental impact are in demand. As a method for reducing environmental impact, material recycling can be cited, in which molded bodies made of thermoplastic resin are collected and reused as materials for molding processing.

[0006] In this specification, the resin material used for molding for the first time after polymerization may be referred to as "virgin material." The molding process at this time does not include the pelletizing process. Furthermore, the resin material obtained by crushing the resin molded body and pelletizing it as necessary may be referred to as "recycled material."

[0007] However, the molecular weight of thermoplastic resins contained in recycled materials may change due to the thermal history during the manufacturing of the original resin molded product. In addition, recycled materials contain various auxiliary materials that are added according to the required physical properties of the original resin molded product. Therefore, it is difficult to stabilize the physical properties of recycled materials, and their characteristics may change from batch to batch.

[0008] This invention has been made in view of these circumstances, and aims to provide a hollow molded container that is easy to stabilize in terms of physical properties while using recycled materials as materials. It also aims to provide a bag-in-box that has such a hollow molded container as an inner bag. [Means for solving the problem]

[0009] To solve the above problems, one aspect of the present invention includes the following aspects.

[0010] [1] A hollow molded container comprising a container body having an internal space for storing contents, and a mouth member provided on the container body, wherein the container body is a molded body of a laminated film made of thermoplastic resin, and the laminated film has a first layer made of virgin material of the thermoplastic resin and a second layer made of recycled material of the thermoplastic resin.

[0011] [2] The hollow molded container according to [1], wherein the total thickness of the first layer and the second layer is 100 μm or more and 800 μm or less, and the ratio of the thickness of the first layer to the thickness of the second layer is 6:4 to 8:2.

[0012] [3] The hollow molded container according to [1] or [2], wherein the first layer is located in the innermost layer of the container body and is exposed to the internal space.

[0013] [4] The hollow molded container according to any one of the items [1] to [3], wherein the thermoplastic resin mainly comprises polyethylene.

[0014] [5] A hollow molded container as described in any one of items [1] to [4], which is the inner bag of a bag-in-box.

[0015] A bag-in-box comprising a hollow molded container as described in [6][5] and a paper outer box for housing the hollow molded container. [Effects of the Invention]

[0016] According to the present invention, it is possible to provide a hollow molded container that can easily maintain stable physical properties even when using recycled materials as materials. Furthermore, it is possible to provide a bag-in-box having such a hollow molded container as an inner bag. [Brief explanation of the drawing]

[0017] [Figure 1] Figure 1 is a perspective view showing the hollow molded container 1 and the bag-in-box 100 according to this embodiment. [Figure 2] Figure 2 is a perspective view showing another form of the hollow molded container 1. [Figure 3] Figure 3 is a schematic diagram showing the cross-sectional structure of the container body 10. [Modes for carrying out the invention]

[0018] The hollow molded container and bag-in-box according to this embodiment will be described below with reference to Figures 1 to 3. Note that in all the following drawings, the dimensions and proportions of each component have been appropriately altered for clarity.

[0019] Hollow molded containers, bag-in-boxes Figure 1 is a perspective view showing a hollow molded container 1 and a bag-in-box 100 according to the present embodiment. Figure 2 is a perspective view showing another configuration of the hollow molded container 1. In the following description, the hollow molded container 1 may be simply referred to as "container 1".

[0020] As shown in Figures 1 and 2, the bag-in-box 100 includes the container 1 and a paper outer box 5 that accommodates the container 1. The container 1 is the inner bag of the bag-in-box 100.

[0021] The container 1 includes a container body 10 having an internal space for storing contents, and a mouth member 20 provided on the container body 10.

[0022] The shape of the container body 10 is not particularly limited, but a substantially cubic shape as shown in Figure 1 is preferred because it is easy to fold and handle. The molding method for the container body 10 is not particularly limited, and for example, known molding methods such as blow molding and vacuum molding can be adopted.

[0023] The mouth member 20 penetrates a part of the upper surface 10x of the container body 10, and connects the internal space of the container body 10 to the outside. A spiral ridge functioning as a male thread is formed on the outer peripheral surface of the mouth member 20. Figure 1 shows a state where a cap 30 is detachably screwed to the tip of the mouth member 20 to seal the mouth member 20.

[0024] The container 1 is composed of a triangular prism-shaped part A and a triangular prism-shaped part B, which are divided along an imaginary plane (diagonal plane) connecting two adjacent corners 10x on the upper surface 10α of the container body 10 and two corners 10y that are not adjacent to the corners 10x on the lower surface 10β. The part A includes the mouth member 20. The part A (excluding the mouth member 20) and the part B are each manufactured by a known production method such as pressure forming, vacuum forming, or blow molding.

[0025] The container 1 is manufactured by making the part A and the part B face each other across the diagonal plane, and heat-sealing the contact portions. The heat-sealed portions become a heat seal portion 1x formed along the edge of the diagonal plane.

[0026] As shown in Figure 2, the container 1 can fold the corner 10z of the top surface 10x along the heat-seal portion 1x toward the internal space of the container body 10.

[0027] The outer box 5 is formed into a rectangular box shape by folding a single blank sheet of cardboard or the like, which has been press-punched into a predetermined shape, and overlapping and gluing the necessary parts together. A through-hole 5a is formed on the top surface of the outer box 5, and the mouth member 20 of the container 1 protrudes from the through-hole 5a to the outside of the outer box 5.

[0028] Figure 3 is a schematic diagram showing the cross-sectional structure of the container body 10. The container body 10 is a molded body of a laminated film made of thermoplastic resin.

[0029] The container body 10 is a molded laminated film having a first layer 11 made of virgin thermoplastic resin as the forming material and a second layer 12 made of recycled thermoplastic resin as the forming material. The thermoplastic resin (virgin material) constituting the first layer 11 and the thermoplastic resin (recycled material) constituting the second layer 12 are the same type of thermoplastic resin.

[0030] (1st layer) The first layer 11 is formed from virgin material and does not contain recycled material. In this specification, terms such as "does not contain," "does not contain," and "is not present" indicate that the substance in question is not present at all in each layer (i.e., 0% by mass), or that when the content of the substance in question (recycled material, etc.) is measured in each layer, its content is below the detection limit.

[0031] The thermoplastic resin constituting the first layer 11 preferably mainly contains polyethylene. As polyethylene, for example, the first layer 11 may mainly contain linear low-density polyethylene (LLDPE). When the first layer 11 is said to "mainly contain linear low-density polyethylene," it means that the content of linear low-density polyethylene is at least 50% by mass or more of the total amount of the first layer 11.

[0032] The first layer 11 may contain 80% by mass or more, or 90% by mass or more, of linear low-density polyethylene relative to the total amount of the first layer 11. There is no particular upper limit to the content, but the amount of linear low-density polyethylene relative to the total amount constituting the first layer 11 may be 100% by mass or less.

[0033] The density of the linear low-density polyethylene contained in the first layer 11 is not particularly limited. For example, the density of the linear low-density polyethylene contained in the first layer 11 is 0.905 g / cm³. 3 The above and 0.925 g / cm³ 3 The following range is acceptable.

[0034] The linear low-density polyethylene contained in the first layer 11 may be, for example, LLDPE C6 obtained by copolymerizing hexene (C6), or LLDPE C8 obtained by copolymerizing octene (C8).

[0035] Examples of additives other than resins that can be included in linear low-density polyethylene include known stabilizers, antistatic agents, antioxidants, lubricants, and antiblocking agents.

[0036] The first layer 11 is preferably located on the internal space side of the container body 10, closer to the internal space than the second layer 12, and is positioned as the innermost layer of the container body 10. In this case, the first layer 11 is exposed to the internal space of the container body 10.

[0037] Generally, recycled resin materials are manufactured from resins derived from various products. Therefore, recycled materials may contain different types of resin materials. When the innermost layer of the container body 10 is made from recycled material, the melting point of the innermost layer of the container body will differ from batch to batch of recycled material. As mentioned above, the innermost layer of the container body is the layer that faces each other and is heat-fused together in the manufacturing of the container body between parts A and B. Therefore, when the innermost layer of the container body 10 is made from recycled material, it may become difficult to control the seal strength of the heat-sealed portion 1x.

[0038] In contrast, because the first layer 11 is located in the innermost layer of the container body 10, the sealing strength of the heat-sealed portion 1x can be easily controlled.

[0039] Furthermore, even if the recycled material is purified during the manufacturing process, it may still contain unintended components. Therefore, there is a concern that if the layer containing the recycled material comes into contact with the contents of container 1, these unintended components may leach into the contents. If the contents are food, beverages, or pharmaceuticals, it is necessary to avoid the leaching of such components, thus limiting the uses of container 1.

[0040] In contrast, since the first layer 11 is located in the innermost layer of the container body 10, the above concerns are eliminated, and the container 1 can be suitably used for various applications.

[0041] (2nd layer) The second layer 12 contains recycled thermoplastic resin. If the thermoplastic resin constituting the first layer 11 is polyethylene, the second layer 12 contains recycled polyethylene (recycled PE).

[0042] The second layer 12 may contain 20% or more by mass of recycled PE relative to the total amount of the second layer 12, or 50% or more by mass. There is no particular upper limit to the content, but recycled PE may be 100% or less by mass relative to the total amount constituting the second layer 12.

[0043] The recycled material that makes up the second layer 12 is recycled material manufactured from the same resin as the thermoplastic resin that makes up the first layer 11. "The same resin" means the same product grade if it is a commercially available product, although the manufacturing batch and product lot may be different.

[0044] More specifically, the recycled material in the second layer 12 should ideally be obtained through post-consumer recycling (PCR), which targets waste collected after consumer use. For example, after selling hollow molded containers manufactured as a company product using virgin material, the used containers can be collected, washed as appropriate, and then recycled material can be manufactured, allowing for the identification of the product grade of thermoplastic resin contained in the recycled material.

[0045] By forming the second layer 12 using recycled material whose origin has been identified in this way, and forming the first layer 11 using virgin material of the same resin, a laminated film, which is the material for the hollow molded container of this embodiment, can be manufactured.

[0046] Furthermore, recycled materials may include not only materials obtained by PCR, but also materials obtained through material recycling (Post Industry Recyclate (PIR)) targeting scraps and substandard products generated during production at factories, etc.

[0047] By forming a first layer 11 using virgin thermoplastic resin (e.g., polyethylene) and a second layer 12 using recycled virgin material, the resulting laminate of the first layer 11 and the second layer 12 is a laminated film made of resin of the same product grade. Such a laminated film can be used to mold a container body 10 (container 1) under the same processing conditions as a laminated film manufactured using only virgin material.

[0048] Furthermore, by unifying the materials of the first layer 11 and the second layer 12 to the same product grade of resin, it is easier to maintain physical properties equivalent to those of a laminated film (container body) manufactured using only virgin material.

[0049] Furthermore, by unifying the materials of the first layer 11 and the second layer 12 to the same product grade of resin, it becomes easier to anticipate the type of substances leaching from the second layer 12, and the container 1 can be used in an appropriate application.

[0050] For example, if the thermoplastic resin constituting the first layer 11 is polyethylene, the recycled material constituting the second layer 12 may contain 5% by mass or more of resins other than polyethylene relative to the total amount of recycled material, or it may contain 15% by mass or more. The upper limit of the content ratio is not particularly limited, but the content of resins other than polyethylene relative to the total amount of recycled material may be 20% by mass or less.

[0051] Examples of optional components other than resin included in the second layer 12 include known additives such as stabilizers, antistatic agents, antioxidants, lubricants, and antiblocking agents.

[0052] The higher the recycled material content in the second layer 12, the lower the environmental impact compared to using only virgin materials in the laminated film.

[0053] The combined thickness of the first layer 11 and the second layer 12 is preferably between 100 μm and 800 μm, and the ratio of the thickness of the first layer 11 to the thickness of the second layer 12 is preferably 6:4 to 8:2. By having a second layer 12 of such thickness, it is possible to reduce the environmental burden while suppressing fluctuations in physical properties caused by the use of recycled materials.

[0054] (Any layer) The laminated film constituting the container body 10 may have any of the following layers, as long as the effects of the invention are not impaired. Hereinafter, the explanation will be given assuming that the virgin material constituting the first layer 11 is virgin polyethylene and the recycled material constituting the second layer 12 is recycled PE.

[0055] (Polyethylene layer) The container body 10 may have a polyethylene layer 13 laminated on the second layer 12. The surface of the polyethylene layer 13 may be the outer surface 10b of the container body 10.

[0056] The polyethylene layer 13 mainly contains polyethylene. "Mainly containing polyethylene" means that the polyethylene content is at least 50% by mass of the total amount constituting the polyethylene layer 13.

[0057] The polyethylene layer 13 may contain 80% by mass or more of polyethylene relative to the total amount of polyethylene layer 13, or 90% by mass or more. There is no particular upper limit to the content, but polyethylene may be 100% by mass or less of the total amount of polyethylene layer 13.

[0058] The polyethylene contained in the polyethylene layer 13 is preferably virgin polyethylene. On the other hand, the polyethylene contained in the polyethylene layer 13 may also include recycled PE. If recycled PE is included, it may be included in an amount that does not significantly degrade the physical properties of the polyethylene layer 13. If recycled PE is included, it may be included in an amount of less than 20% by mass of the total amount constituting the polyethylene layer 13, and may be 10% by mass or less, 5% by mass or less, or 3% by mass or less.

[0059] The polyethylene contained in the polyethylene layer 13 may be ultra-low density polyethylene, low density polyethylene (LDPE), medium density polyethylene (MDPE), or high density polyethylene (HDPE). The polyethylene contained in the polyethylene layer 13 may be linear or branched. Furthermore, the polyethylene contained in the polyethylene layer 13 may also include modified polyethylene (e.g., EVOH, Admer® (manufactured by Mitsui Chemicals, Inc.)).

[0060] Examples of optional components other than resin included in the polyethylene layer 13 include known additives such as stabilizers, antistatic agents, antioxidants, lubricants, and antiblocking agents.

[0061] (colored layer) The container body 10 may have a colored layer 14 on the outer surface side of the second layer 12.

[0062] The colored layer 14 mainly contains polyethylene. "Mainly containing polyethylene" means that the polyethylene content is at least 50% by mass of the total amount of the colored layer 14.

[0063] The colored layer 14 may contain 80% by mass or more of polyethylene, or 90% by mass or more, relative to the total amount of the colored layer 14. There is no particular upper limit to the content, but the polyethylene may be 100% by mass or less relative to the total amount of the colored layer 14.

[0064] The polyethylene contained in the colored layer 14 may be virgin polyethylene. On the other hand, the polyethylene contained in the colored layer 14 may also include recycled PE. If recycled PE is included, it may be included in an amount that does not significantly degrade the physical properties of the colored layer 14. If recycled PE is included, the recycled PE may be included in an amount of less than 20% by mass of the total amount of the colored layer 14, and may be 10% by mass or less, 5% by mass or less, or 3% by mass or less.

[0065] The polyethylene contained in the colored layer 14 may be ultra-low density polyethylene, low density polyethylene (LDPE), medium density polyethylene (MDPE), or high density polyethylene (HDPE). The polyethylene contained in the colored layer 14 may be linear or branched. Furthermore, the polyethylene contained in the colored layer 14 may also include modified polyethylene (e.g., EVOH, Admer® (manufactured by Mitsui Chemicals)).

[0066] The colored layer 14 contains a coloring agent. A general-purpose colored masterbatch can be used as the coloring agent. The colored layer 14 may also be a layer formed by printing. In this case, the colored layer 14 may be a layer in which the inks used in printing are laminated.

[0067] Recycled PE is manufactured from polyethylene derived from various products, resulting in inconsistent coloration. Furthermore, because recycled PE contains a mixture of colors from different products, it's difficult to achieve a desired color. Therefore, films where the second layer 12 is visible may have an undesirable appearance. By using a colored layer, the appearance of the film can be controlled.

[0068] Instead of adding a colored layer to the film's structure, the second layer 12 may contain a coloring agent. However, since recycled PE is manufactured from polyethylene derived from various products, it may contain different types of polyethylene. Therefore, recycled PE may have different shades from batch to batch. Adjusting the type and amount of coloring agent added to match the recycled PE used is time-consuming in film manufacturing, so it is preferable for the film to have a colored layer rather than adding a coloring agent to the second layer 12.

[0069] If the color of the colored layer 14 is gray or black, it can make the color differences resulting from variations in the quality of recycled PE less noticeable.

[0070] Instead of providing the colored layer 14, at least one of the second layer 12 and the polyethylene layer 13 may be colored. Alternatively, in addition to the colored layer 14, at least one of the second layer 12 and the polyethylene layer 13 may also be colored.

[0071] The amount of coloring agent contained in the colored layer 14 may be 5% by mass or less of the total amount constituting the container body 10. By limiting the coloring agent content to at most 5% by mass of the total amount constituting the container body 10, the recyclability of the container body 10 is not impaired. Since the container body 10 can be easily used as a raw material for recycled PE, further reduction of environmental impact can be aimed for. Furthermore, the lower limit of the coloring agent content is not limited as long as the container body 10 can be appropriately colored, but it is generally 1% by mass or more.

[0072] Examples of optional components other than the resin and colorant included in the colored layer 14 include known additives such as stabilizers, antistatic agents, antioxidants, lubricants, and antiblocking agents.

[0073] (Elution suppression layer) The container body 10 may have an elution-inhibiting layer 15 between the first layer 11 and the second layer 12.

[0074] The elution-inhibiting layer 15 mainly contains a resin with a higher glass transition temperature (Tg) than polyethylene. The statement that the elution-inhibiting layer 15 "mainly contains a resin with a higher Tg than polyethylene" means that the content of a resin with a higher Tg than polyethylene is at least 50% by mass of the total amount constituting the elution-inhibiting layer 15.

[0075] The elution-inhibiting layer 15 may contain 80% or more by mass of a resin with a Tg higher than polyethylene, or 90% or more by mass, relative to the total amount of the elution-inhibiting layer 15. There is no particular upper limit to the content, but the amount of resin with a Tg higher than polyethylene may be 100% or less by mass, relative to the total amount of the elution-inhibiting layer 15.

[0076] The resin with a higher Tg than the polyethylene contained in the elution-inhibiting layer 15 is preferably a virgin resin, but may also contain recycled resin. If recycled resin is included, it may be included in an amount that does not significantly degrade the physical properties of the elution-inhibiting layer 15. If recycled resin is included, it may be included in an amount of less than 20% by mass of the total amount of the elution-inhibiting layer 15, and may be 10% by mass or less, 5% by mass or less, or 3% by mass or less.

[0077] Examples of optional components other than resin included in the elution-inhibiting layer 15 include known additives such as stabilizers, antistatic agents, antioxidants, lubricants, and antiblocking agents.

[0078] Even after purification during the production process of recycled PE, the possibility of unintended components being present and leaching cannot be completely eliminated. Therefore, by placing the leaching suppression layer 15 between the first layer 11 and the second layer 12, the leaching of unintended components into the internal space of the container body 10 can be suppressed.

[0079] Similarly, to prevent unintended components contained in recycled PE from leaching into the outermost layer of the container body 10, an elution-inhibiting layer may be provided between the second layer 12 and the outermost layer.

[0080] For resins with a higher Tg than polyethylene, the Tg is preferably -10°C or higher, and may be, for example, 40°C or higher. The upper limit of Tg is not limited, but generally 160°C or lower is preferred.

[0081] For resins with a higher Tg than polyethylene, ethylene-based resins are preferred. Since the layers other than the elution-inhibiting layer 15 mainly contain polyethylene, using ethylene-based resins makes it easy to use the container body 10 as a raw material for recycled PE, thereby aiming for further reduction of environmental impact. Examples of ethylene-based resins include polyethylene vinyl alcohol (ethylene vinyl alcohol copolymer, EVOH) and ethylene vinyl acetate copolymer (EVA). For ethylene-based resins with a higher Tg than polyethylene, EVOH is preferred.

[0082] Resins with a higher Tg than polyethylene may be non-ethylene-based resins. Examples of non-ethylene-based resins include polypropylene, polyester, cyclic olefins, and polyvinyl alcohol.

[0083] The container body 10 includes a polyethylene layer 13, a colored layer 14, a second layer 12, an elution-inhibiting layer 15, and a first layer 11. Other layers may be introduced as needed, and a stretched polyethylene film may be further laminated at any position on the side where the recycled polyethylene layer of the linear low-density polyethylene layer is laminated (i.e., the outer surface 10b side).

[0084] The total content of ethylene-based resin (e.g., polyethylene) in the container body 10 may be 80% by mass or more, or 90% by mass or more, relative to the total amount of resin constituting the container body 10. By doing so, the container body 10 can be easily used as a raw material for recycled PE as a monomaterial of ethylene-based resin (e.g., polyethylene), thereby aiming for further reduction of environmental impact.

[0085] The laminated film constituting the container body 10 can be manufactured by known methods. For example, the container body 10 can be manufactured by co-extruding the resins that serve as raw materials for each layer, such as the polyethylene layer 13, the colored layer 14, the second layer 12, the elution-inhibiting layer 15, and the first layer 11, after heating and melting them separately.

[0086] With the hollow molded container 1 configured as described above, it is possible to create a hollow molded container that can easily maintain stable physical properties even when using recycled materials as materials.

[0087] Furthermore, a bag-in-box with the above configuration can be made using recycled materials while maintaining a certain level of quality.

[0088] In this embodiment, the hollow molded container is used as the inner bag of the bag-in-box, but this is not the only option. The hollow molded container may be used on its own without using the outer box 5.

[0089] Preferred embodiments of the present invention have been described above with reference to the attached drawings, but the present invention is not limited to these examples. The shapes and combinations of the constituent members shown in the above examples are merely examples, and can be modified in various ways based on design requirements, etc., without departing from the spirit of the present invention. [Examples]

[0090] The present invention will be described below with reference to examples, but the present invention is not limited to these examples.

[0091] (Example 1) Virgin material (LLDPE C6, density = 0.922 g / cm³) 3 Using a material with an MFR of 2.0 and recycled material, a laminated film of Example 1 consisting of two layers, a first layer 11 and a second layer 12, was manufactured by co-extrusion. The recycled material was obtained by crushing and repelling a hollow molded container (the hollow molded container of Comparative Example 1 described later) manufactured using virgin material. The layer thickness of the laminated film was 330 μm, and the ratio of the thickness of the first layer 11 to the second layer 12 was 7:3. Using the obtained laminated film, the above parts A and B were manufactured by vacuum forming and then heat-sealed to produce the hollow molded container of Example 1.

[0092] (Comparative Example 1) Instead of recycled materials, virgin material (LLDPE C6, density = 0.922 g / cm³) is used. 3 A laminated film of Comparative Example 1 was manufactured in the same manner as in Example 1, except that an MFR of 2.0 was used. Using the obtained laminated film, parts A and B were manufactured by vacuum forming and then heat-sealed to produce a hollow molded container of Comparative Example 1.

[0093] Test specimens were cut from the manufactured hollow molded containers, and the following evaluations were performed.

[0094] (Strength assessment) The fracture strength (in MPa) and fracture elongation (%) of the manufactured test specimens were measured according to JIS K 7161. Measurements were performed with n=5, and the arithmetic mean of each measurement value was adopted as the measurement result.

[0095] (Folding strength evaluation) The bending strength (number of cycles) of the manufactured test specimens was measured according to JIS P 8115 (MIT testing machine method). Measurements were performed with n=3, and the arithmetic mean of each measurement value was adopted as the measurement result.

[0096] (Material testing (residual additives)) Based on the standards and specifications for food and food additives (Ministry of Health and Welfare Notification No. 370 of 1959), we confirmed whether the amount of cadmium and lead contained in the manufactured test specimens met the standards and specifications.

[0097] In accordance with the standards and specifications for food additives, etc. (Ministry of Health and Welfare Notification No. 370 of 1959), elution tests were conducted using manufactured test pieces to confirm the amount of each substance eluted. For substances that are oxidized by potassium permanganate, the amount of potassium permanganate consumed was used for evaluation.

[0098] The evaluation results are shown in Table 1.

[0099] [Table 1]

[0100] The evaluation results showed that the laminated film of Example 1 exhibited physical properties comparable to those of the laminated film of Comparative Example 1.

[0101] Based on the above results, it has been confirmed that the present invention is useful. [Explanation of Symbols]

[0102] 1...Hollow molded container, 5...Outer box, 10...Container body, 11...First layer, 12...Second layer, 13...Polyethylene layer, 14...Colored layer, 15...Elution-inhibiting layer, 100...Bag-in-box

Claims

1. A container body having an internal space for storing contents, The container body comprises a mouth member provided on the container body, The container body is a molded body of a laminated film made of thermoplastic resin, The laminated film comprises a first layer formed from the virgin material of the thermoplastic resin, A hollow molded container having a second layer formed from recycled thermoplastic resin.

2. The total thickness of the first layer and the second layer is 100 μm or more and 800 μm or less. The hollow molded container according to claim 1, wherein the ratio of the thickness of the first layer to the thickness of the second layer is 6:4 to 8:

2.

3. The hollow molded container according to claim 1 or 2, wherein the first layer is located in the innermost layer of the container body and is exposed to the internal space.

4. The hollow molded container according to claim 1 or 2, wherein the thermoplastic resin mainly comprises polyethylene.

5. A hollow molded container according to claim 1 or 2, which is the inner bag of a bag-in-box.

6. A hollow molded container according to claim 5, A bag-in-box comprising a paper outer box for housing the aforementioned hollow molded container.

Images