JP7654962B2 - Laminated sheet for tube container and tube container - Google Patents

Description

This disclosure relates to a laminate sheet for tube containers and tube containers.

Tube containers are filled and packaged with the contents, and the required amount can be squeezed out at the time of use. For this reason, tube containers are widely used as containers for food, cosmetics, medicines, etc.

Such tube containers are usually composed of a body whose main component is synthetic resin, and a head member including a mouth (for example, Patent Document 1).

Japanese Patent Application Publication No. 5-220900

However, with the recent rise in environmental protection sentiment, there is a growing demand for environmentally friendly containers that can be easily crushed to reduce their volume.

This disclosure was made in light of these circumstances, and aims to provide a laminate sheet for tube containers and a tube container that can be easily reduced in volume when disposed of.

That is, the laminate sheet for a tube container of the present disclosure is a laminate sheet that constitutes the body of a tube container, and the laminate sheet has an outer layer and an inner layer arranged in order from the outer surface to the inner surface, the outer layer includes, in order from the outer surface, a first sealant layer and a base layer, the outer layer has a cut line, the inner layer includes a second sealant layer, and the inner layer has an easily peelable layer on the surface that contacts the outer layer.

The tube container of the present disclosure also comprises a cylindrical body member formed by overlapping and joining opposing ends of the laminate sheet for tube containers described above, and a head member joined to one end of the cylindrical body member, the head member including a shoulder portion and a mouth portion.

The present disclosure has the effect of providing a laminate sheet for tube containers and a tube container that can be easily reduced in volume when disposed of.

FIG. 2 is a partial vertical cross-sectional view showing the tube container according to the present embodiment with a cap attached. FIG. 2 is a partial vertical cross-sectional view showing the tube container according to the present embodiment filled with contents. FIG. 2 is a partial vertical cross-sectional view of the tube container according to the present embodiment with a portion of the outer layer cut away. FIG. 2 is a partial vertical cross-sectional view of a shrunk tube container with a portion of the outer layer cut away according to the present embodiment. 2 is a cross-sectional view taken along the line XX in FIG. 1 . FIG. 6 is a cross-sectional view showing another laminate sheet of FIG. 5 . FIG. 6 is a cross-sectional view showing another laminate sheet of FIG. 5 . 4A to 4C are diagrams showing a method for manufacturing a tube container.

Hereinafter, an embodiment of the present disclosure will be described with reference to the drawings. Figs. 1 to 8 are diagrams showing one embodiment of the present disclosure. Furthermore, the numerical values such as dimensions of each component and the names of materials described in this specification are examples of an embodiment, and are not limited thereto, and may be appropriately selected and used.

FIG. 1 is a partial cross-sectional view of a tube container according to this embodiment with a cap attached.
As shown in Fig. 1, the tube container 10 includes a body 50 formed of a laminate sheet 55 described below, and a head member 40 fabricated by providing a synthetic resin to the body 50 by a method such as compression molding or injection molding. The head member 40 further includes a shoulder portion 12 and a mouth portion 11. A cap 20 is attached to the mouth portion 11 of the tube container 10. Furthermore, a cut line 13 for peeling off the outer layer 1 is formed in the body 50. The cut line 13 goes around the cylindrical body 50. A notch 14 is formed in the side seal portion 18 of the body 50, connecting with the first cut line 13a and the second cut line 13b.

FIG. 2 is a partial cross-sectional view of a packaged product of a tube container 10A filled with contents.
As shown in FIG. 2, a tube container 10A filled with contents comprises a multi-layer outer layer 1 forming an outer shell, and an inner layer 2 which is freely shrinkable and deformable and which contains the contents. The outer layer 1 and the inner layer 2 are joined and fixed at a connecting portion of a head member at the upper end and a bottom seal portion 17 at the lower end.

FIG. 3 is a partial vertical cross-sectional view of a tube container 10B according to this embodiment with a portion of the outer layer cut away.
3, when the tube container 10A filled with contents is to be disposed of after use, a part of the outer layer 1 is cut off along the first cut line 13a and the second cut line 13b to reveal the inner layer 2 located inside the cut outer layer 1. Here, the first cut line 13a and the second cut line 13b refer to imaginary lines along which the outer layer 1 of the tube container 10B is cut off.
By cutting the outer layer 1 along the first cut line 13a and the second cut line 13b in a strip shape, the body 50 is divided into two parts, upper and lower, sandwiching the exposed inner layer 2. Hereinafter, the upper part of the body 50 divided into two parts will be referred to as the upper body 50a and the lower part will be referred to as the lower body 50b.

The above-mentioned cut line 13 can be formed across the entire width of the body of the tube container 10 at the portion of the outer layer 1 to be peeled off. By providing the cut line 13 in a straight line, the outer layer 1 can be easily cut off. By peeling off the outer layer 1, the volume of the tube container can be reduced, and the environmental burden can be reduced.

The number of cut lines 13 may be one or more.
The shape of the cut line 13 can be freely formed, and it is possible to form a half cut, a dotted line, less than, greater than, tortoise shell brackets, a slash, a plus, or other shapes.
The position of the first cut line 13a is not particularly limited, but from the standpoint of reducing the volume of the tube container, it is preferable, for example, to provide the first cut line 13a at a position 5.0 mm to 10.0 mm below the position on the side of the body of the tube container that will be joined to the head member, and to provide the second cut line 13b at a position 5.0 mm to 10.0 mm above the position on the bottom side of the body of the tube container.

FIG. 4 is a partial vertical sectional view of a tubular container B according to this embodiment, with a part of the outer layer 1 cut away, in a contracted state.
As shown in FIG. 4, when a tube container B, from which a portion of the outer layer 1 has been cut into a strip shape, is pressed against a lower body portion 50b, the inner layer 2 sandwiched between the upper body portion 50a and the lower body portion 50b is deformed, thereby reducing the volume of waste in the tube container.

The tube container 10 having such a configuration is obtained through the following manufacturing process.

Using a laminate sheet 55 for the cylindrical body of a tube container according to the present disclosure described below, both ends of the laminate sheet 55 for a tube container described below are overlapped and the outside and inside of the overlapped portion are heat sealed to form a side seal portion 18, thereby manufacturing the cylindrical body. Next, the cylindrical body is placed in a mold, and a shoulder portion and a mouth portion are formed at one opening of the cylindrical body portion 50 by a method such as compression molding. In this way, the shoulder portion and the mouth portion are integrally molded at one opening of the cylindrical body portion, and the tube container 10 is produced. Then, a cap 20 is attached to the mouth portion of the tube container 10 (see FIG. 1).

At the other opening of the cylindrical body 50, a bottom seal portion 17 is formed by joining together laminate sheets 55 for tube containers, which will be described later. This bottom seal portion 17 is formed by joining together laminate sheets 55 for tube containers, which will be described later, near the opening 16 formed at the other end of the cylindrical body 50 after, for example, an appropriate amount of contents C is filled through the opening 16. (See FIG. 2)

Next, the laminate sheet 55 for tube containers according to this embodiment will be described with reference to Figures 5 to 7. Figure 5 is a cross-sectional view taken along the line X-X in Figure 1. As shown in Figure 5, the portion of the laminate sheet 55 for tube containers where the outer layer 1 is to be peeled off has a double structure having the outer layer 1 and the inner layer 2, and has an easily peelable layer 52 on the surface that contacts the outer layer 1 and the inner layer 2. The outer layer 1 also has a cut line 13 for peeling.

In this embodiment, the cut line 13 formed in the outer layer 1 of the tube container 10 is formed by laser processing.

The outer layer 1 includes a first sealant layer 56, a first adhesive layer 57a, and a base layer 58, arranged in this order from the outside to the inside. The inner layer 2 includes an easily peelable layer 52 and a second sealant layer 59.

As shown in FIG. 6, in the laminate sheet 55 for tube containers, the outer layer 1 includes a first sealant layer 56, a first adhesive layer 57a, and a base layer 58 arranged in this order from the outside to the inside, and may further include a second adhesive layer 57b and a light-shielding barrier layer 60. The inner layer 2 includes an easily peelable layer 52 and a second sealant layer 59.

As shown in FIG. 7, in the laminate sheet 55 for tube containers, the outer layer 1 includes a first sealant layer 56, a first adhesive layer 57a, and a base layer 58, which are arranged in this order from the outside to the inside, and may further include a second adhesive layer 57b and a light-shielding barrier layer 60. The inner layer 2 may include an easily peelable layer 52, an intermediate layer 61, an oil barrier layer 62, and a second sealant layer 59.

In the laminate sheet 55 for tube containers shown in Figures 5 and 6, a printed layer may be provided, for example, on the inside of the base layer 58 by reverse printing.

In this specification, "outside" and "inside" refer to the "outside" and "inside" when a tube container 10 is produced using the tube container laminate sheet 55.

Next, we will explain each layer of the laminate sheet 55 for tube containers.

The first sealant layer 56 and the second sealant layer 59 are layers for bonding the tube container laminate sheets 55 together. The materials constituting the first sealant layer 56 and the second sealant layer 59 may be any materials that melt and fuse when heated.

The first sealant layer 56 and the second sealant layer 59 may be made of any material that can be melted and fused to each other by heat, and may be made of one or more of the following resins: low-density polyethylene (LDPE), medium-density polyethylene (MDPE), high-density polyethylene (HDPE), linear low-density polyethylene (LLDPE), very low-density polyethylene, polypropylene (PP), ethylene-vinyl acetate copolymer, ionomer resin, ethylene-ethyl acrylate copolymer, ethylene-acrylic acid copolymer, ethylene-methacrylic acid copolymer, ethylene-propylene copolymer, methylpentene polymer, acid-modified polyolefin resins obtained by modifying polyolefin resins such as polyethylene or polypropylene with unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic acid, maleic anhydride, fumaric acid, itaconic acid, and others; polyvinyl acetate resins; polyester resins; polystyrene resins; and others.

In this embodiment, among the above, low-density polyethylene film is easy to handle and is preferred.

In this embodiment, for example, one or more of the above resins are used as the main component, and desired additives are optionally added to this to prepare a resin composition, and then the resin composition prepared as above can be used.

In addition, materials containing optional additives such as antiblocking agents, lubricants (fatty acid amides, etc.), flame retardants, and inorganic or organic fillers may be used.

In this embodiment, the thickness is preferably 10 μm or more and 200 μm or less, and more preferably 60 μm or more and 150 μm or less. If it is within the above range, it can be easily manufactured by the inflation molding method.

It is preferable that the first sealant layer 56 allows the printing layer formed on the base layer 58 to be seen through.

In addition, in this embodiment, it is preferable that the thickness of the first sealant layer 56 is thinner than the thickness of the second sealant layer 59. By not making the thickness of the first sealant layer too thick, it is possible to prevent a decrease in the visibility of the printed layer when the printed layer is provided on the inside of the base layer 58 by reverse printing. This makes it possible to prevent a decrease in the design of the cylindrical body of the tube container.

In this embodiment, the first sealant layer 56 and the second sealant layer 59 may be made, for example, by preparing a resin composition using one or more of the above-mentioned resins as the main component and optionally adding desired additives thereto, and then using the resin composition prepared above, a film or sheet may be formed, for example, using the T-die method, inflation molding method, or other molding method.

The base layer 58 can be a basic material that constitutes the tube container 10 and is made of a material that has strength, toughness, and heat resistance.

Materials that can be used to form the base layer 58 include, for example, polyester resin, polyamide resin, polyaramid resin, polyolefin resin, polycarbonate resin, polyacetal resin, fluorine resin, and other tough resin films or sheets, and the like.

Among the above, polyester resins, especially polyethylene terephthalate (PET) resins, are preferred in terms of printability. Here, polyethylene terephthalate resins refer to pure polyethylene terephthalate resins and various modified polyethylene terephthalate resins.

The base layer 58 can be an unstretched film or a uniaxially or biaxially stretched film. Among them, in this embodiment, a biaxially stretched polyester resin film is preferred because of its excellent printability. Also, according to this embodiment, the base layer 58 can be made easy to open by the biaxial stretching process.

In this embodiment, the thickness of the base layer 58 is preferably 10 μm or more and 25 μm or less.

As shown in FIG. 6, the cut line 13 is formed in the outer layer 1 that constitutes the body 50, but is not formed in the inner layer 2. Therefore, the area where the outer layer 1 is cut along the cut line remains covered by the oil barrier layer 62 and the gas barrier layer, and the oil barrier property and gas barrier property in the inner layer, which will be described later, can be maintained.

It is also preferable that the cut line 13 is not formed in the light-shielding barrier layer 60 in the outer layer 1. If the cut line 13 is formed up to the light-shielding barrier layer 60, there is a risk that the gas barrier properties and light-shielding properties of the tube container 10 will be reduced.

Also, preferably, the score line 13 formed in the outer layer 1 penetrates at least the first sealant layer 56 and the base layer 58 of the outer layer 1. By having the score line 13 penetrate the high-strength base layer 58, the outer layer 1 that constitutes the body 50 of the tube container 10 can be easily peeled off along the score line 13.

In addition, in this disclosure, as shown in FIG. 1, a notch 14 may be provided on one or both sides of the widthwise end of the score line 13 to further improve ease of opening.

The printing layer is used to form patterns on the tube container.

The printed layer can be formed on the above-mentioned base material layer 58 by a printing method such as gravure printing, letterpress printing, screen printing, transfer printing, flexographic printing, ink-jet printing, or the like.
The design is not particularly limited, and examples include letters, figures, symbols, patterns, and the like.
It is preferable that the print layer is formed on the back surface of the base layer 58 rather than on the outermost surface, since this can prevent damage to the design layer due to external impact.

The printing layer may be made of an ink composition that contains one or more of the usual ink vehicles as the main component, and optionally contains one or more of the following additives, such as plasticizers, stabilizers, antioxidants, light stabilizers, UV absorbers, curing agents, crosslinking agents, lubricants, antistatic agents, fillers, and other additives, if necessary, and further contains a colorant such as a dye or pigment, and is thoroughly kneaded with a solvent, diluent, etc. to prepare the ink composition. Examples of such ink vehicles include linseed oil, tung oil, soybean oil, hydrocarbon oil, rosin, rosin ester, rosin-modified resin, shellac, alkyd resin, phenolic resin, maleic acid resin, natural resin, hydrocarbon resin, polyvinyl chloride resin, polyacetic acid resin, polystyrene resin, polyvinyl butyral resin, acrylic or methacrylic resin, polyamide resin, polyester resin, polyurethane resin, epoxy resin, urea resin, melamine resin, aminoalkyd resin, nitrocellulose, ethyl cellulose, chlorinated rubber, cyclized rubber, and others, which can be used alone or in combination of two or more.

The light-shielding barrier layer 60 has a vapor barrier property that prevents the transmission of water vapor and a gas barrier property that prevents the transmission of gases such as oxygen gas.

In addition, the light-shielding barrier layer 60 also has the function of preventing light from reaching the contents in the tube container 10, thereby preventing deterioration of the quality of the contents, i.e., light-shielding properties. The light to be blocked by the light-shielding barrier layer 60 is mainly visible light and ultraviolet light, consisting of external light in the wavelength range of, for example, 300 to 800 nm, which is incident on the tube container laminate sheet 55 under normal use conditions. It is also preferable that the light-shielding barrier layer 60 also blocks infrared light, for example, with a wavelength exceeding 800 nm, as much as possible.

The light-shielding barrier layer 60 is not particularly limited as long as it satisfies the above-mentioned functions. In the present embodiment, the light-shielding barrier layer 60 may be a metal foil, a metal foil to which a PET film is attached, a metal-deposited film, or the like, and examples of the metal include aluminum, copper, stainless steel, and the like. In the present embodiment, a layer made of aluminum is preferable.
The term "aluminum layer" as used herein refers to a layer containing aluminum as a main component, and includes aluminum alloys and the like as long as the layer contains aluminum as a main component. When the light-shielding barrier layer 60 contains aluminum as a main component, the light-shielding barrier layer 60 exhibits extremely excellent gas barrier properties, light-shielding properties, and concealing properties. Typical examples of the aluminum layer include aluminum foil and aluminum alloy foil.

The thickness of the light-shielding barrier layer 60 is usually 5 to 40 μm, and preferably 7 to 20 μm. If the thickness is less than 5 μm, there is a risk that sufficient gas barrier properties will not be obtained for use as a tube container 10. On the other hand, if the thickness exceeds 40 μm, the environmental load will increase, which is not preferable.

The laminate sheet 55 for tube containers can further have an oil barrier layer 62 in the inner layer 2. This oil barrier layer 62 is a layer for preventing oil in the contents of the tube container 10 from leaking out to the outside. This oil barrier layer 62 contains ethylene-vinyl alcohol copolymer (EVOH). By containing the ethylene-vinyl alcohol copolymer in the oil barrier layer 62, the oil barrier properties of the oil barrier layer 62 can be improved. This makes it possible to prevent oil contained in the contents from leaking out to the outside of the tube container 10.

The thickness of the oil barrier layer 62 can be approximately 10 μm or more and 30 μm or less.

The content of the barrier resin in the oil barrier layer 62 is preferably 50% by mass or more and 95% by mass or less, and more preferably 75% by mass or more and 90% by mass or less. By making the content of the barrier resin in the oil barrier layer 62 50% by mass or more, the oil barrier properties can be further improved.

In addition, according to this embodiment, the laminate sheet 55 for tube containers may further have a gas barrier layer between the intermediate layer 61 and the oil barrier layer 62. This can improve the gas barrier properties of the laminate sheet 55 for tube containers.

The gas barrier layer is a layer for preventing the permeation of oxygen gas, water vapor, and the like. For example, a gas barrier material against oxygen gas, water vapor, and the like, a light-shielding material against sunlight, and a material that has aroma retention properties for the contents can be used as the gas barrier layer. Specifically, for example, aluminum foil, tin, lead, copper, iron, nickel, or alloys thereof, or a thin layer of metal vapor deposition such as aluminum can be used as the gas barrier layer. When aluminum foil is used as the gas barrier layer, the thickness of the gas barrier layer can be about 5 μm or more and 20 μm or less.

Furthermore, when a metal vapor deposition layer of aluminum or the like is used as the gas barrier layer, a vapor deposition thin film of a metal such as aluminum can be formed on a support layer by using a physical vapor deposition method (PVD method) such as a vacuum deposition method, a sputtering method, an ion plating method, or a cluster ion beam method.
When a metal vapor-deposited aluminum layer is used as the gas barrier layer, the thickness of the gas barrier layer is usually preferably about 5 nm to about 300 nm, more preferably about 10 nm to about 200 nm. In addition, the surface of the support layer supporting the above-mentioned vapor-deposited aluminum thin film can be coated in advance with, for example, a vapor deposition primer in order to increase the adhesion of the vapor-deposited film, and other required pretreatments can be optionally performed.

The gas barrier layer may also be a transparent vapor deposition layer that can be formed by a conventionally known method. In this case, the gas barrier layer may be a transparent vapor deposition layer made of a vapor deposition layer of an inorganic oxide.

The easily peelable layer 52 is formed on the surface side of the inner layer 2 that contacts the outer layer 1. Specifically, the easily peelable layer 52 is formed on the second sealant layer 59 or the intermediate layer 61. It is preferable that the easily peelable layer 52 is formed at least in the area where the outer layer 1, sandwiched between the areas that will become the upper body portion 50a and the lower body portion 50b, will be cut off.

The easily peelable layer 52 can be made of a coating liquid that is a mixture of silicone compounds, fluorine-based resins, polyamide-based resins, nitrocellulose, and cyclized rubber, or a mixture of these.

Among the coating materials, silicone compounds are particularly preferred in terms of heat resistance. The content of the silicone compound is usually 20% by weight or less, and preferably 0.5 to 20% by weight. If the silicone compound content is more than 20% by weight, the coating film becomes sticky and the cost becomes high, and if it is less than 0.5% by weight, the effect of improving releasability is not sufficient.

The coating amount of the easily peelable layer 52 after drying is preferably 0.05 g/m ² or more and 0.5 g/m ² or less, or 0.05 μm or more and 0.5 μm or less.

The method of laminating the outer layer 1 and the inner layer 2 is preferably to bond the outer layer 1 and the inner layer 2 by thermal lamination. When the easily peelable layer 52 is mainly composed of a silicone compound, it becomes plastic when heated and tack occurs. Therefore, a laminated sheet can be produced by thermally laminating the outer layer 1 and the inner layer 2.

The temperature for thermal lamination is, for example, 80 to 200°C, preferably 100 to 190°C, and more preferably 120 to 180°C. This is because when the easily peelable layer 52 is mainly composed of a silicone compound, plasticity is expressed at temperatures of 80°C or higher.

The peel strength between the outer layer 1 and the inner layer 2 is preferably 0.1 N/15 mm width to 0.7 N/15 mm width. If the peel strength exceeds 0.7 N/15 mm width, it may be difficult to peel the outer layer 1 and the inner layer 2. If it is less than 0.1 N/15 mm width, there is a risk that the tube container may peel off during transportation.

The first adhesive layer 57a and the second adhesive layer 57b are layers for adhering the first sealant layer 56, the base layer 58, the light-shielding barrier layer 60, etc. The adhesive layer can be appropriately selected depending on the resin that constitutes the layer to be adhered.

As the adhesive layer, any of the following can be used: anchor coating agents such as isocyanate-based (urethane-based), polyethyleneimine-based, polybutadiene-based, and organic titanium-based, or anchor coating agents such as polyurethane-based, polyacrylic-based, polyester-based, epoxy-based, polyvinyl acetate-based, cellulose-based, and other laminating adhesives, laminating adhesives, etc.

As the adhesive layer, for example, polyethylene, polypropylene, linear low-density polyethylene, ethylene-vinyl alcohol, ethylene-methacrylic acid copolymer, ethylene-acrylic acid copolymer, ionomer, maleic anhydride modified polyolefin resin, etc. can be suitably used.

In this embodiment, the thickness of the adhesive layer is preferably 3 μm or more and 60 μm or less.

The adhesive strength of the adhesive layer is preferably 3N/15mm or more and 10N/15mm or less, and more preferably 5N/15mm or more and 8N/15mm or less.

Methods for laminating the first sealant layer 56, the base layer 58, the light-shielding barrier layer 60, the gas barrier layer, and the like that form the outer layer 1 include, for example, wet lamination, dry lamination, solventless dry lamination, extrusion lamination, T-die co-extrusion molding, co-extrusion lamination molding, inflation molding, and any other method. When carrying out the above-mentioned lamination, if necessary, the film can be subjected to pretreatment such as corona treatment or ozone treatment.

In addition, the laminate sheet 55 for tube containers may have an intermediate layer 61 provided in the inner layer 2 as necessary. The intermediate layer 61 is provided to adjust the thickness of the laminate sheet 55 for tube containers. An olefin resin may be used for the intermediate layer 61. More specifically, it is preferable to use a polyethylene film such as low density polyethylene, linear low density polyethylene, or medium density polyethylene as the intermediate layer 61. The thickness of the intermediate layer 61 is preferably, for example, 50 μm or more and 200 μm or less.

In addition, in order to facilitate deformation when discarding the tube container, multiple lines 2a (grooves) may be provided on the top and bottom of either or both of the outer layer 1 and the inner layer 2. By providing lines 2a, it is possible to make the container bellows-like (see Figure 4).

As described above, the tube container laminate sheet 55 includes the first sealant layer 56, the base layer 58, the light-shielding barrier layer 60, and the second sealant layer 59 in this order from the outer side of the container to the inner side of the container. The aluminum light-shielding barrier layer 60 is less likely to melt than the first sealant layer 56 and the base layer 58, and also scatters the laser light on its surface, making it less likely to be melted than the first sealant layer 56 and the base layer 58. Therefore, by appropriately irradiating the tube container laminate sheet 55 with laser light from the outside of the outer layer 1, it is possible to form the first cut line 13a and the second cut line 13b up to the first sealant layer 56 and the base layer 58, but not in the light-shielding barrier layer 60. When the outer layer 1 is peeled off, the aluminum light-shielding barrier layer 60 can be easily peeled off by following the outer layer 1.

The type of laser used for irradiation includes a YAG laser and a _CO2 laser (carbon dioxide gas laser).

Next, we will explain the head member 40 of the tube container 10.

The head member 40 has a mouth portion 11 and a shoulder portion 12 provided below the mouth portion 11. The shoulder portion 12 also has a circular shape in horizontal cross section.

The head member 40 is made of a resin material such as high-density polyethylene (HDPE). In addition to the high-density polyethylene, the head member 40 of the tube container 10 may also be made of an ethylene-α-olefin copolymer polymerized using a metallocene catalyst.

Next, the cylindrical body 50 will be described. The body 50 of the tube container 10 shown in Figure 1 has a generally cylindrical shape. This body 50 is composed of a laminated tube container laminate sheet 55 (see Figures 5 to 7), and is obtained by rolling this tube container laminate sheet 55 into a cylindrical shape, overlapping opposing ends, and joining them together, for example, by heat sealing. Therefore, the body 50 has side seal portions 18 where the tube container laminate sheets 55 are joined together along the longitudinal direction.

In terms of the thickness of the body 50, the outer layer 1 is preferably, for example, 100 μm or more and 210 μm or less. When the thickness of the outer layer is 100 μm or more, a predetermined strength can be maintained in the body of the tube container 10. This allows the shape retention of the tube container 10 to be maintained. Furthermore, when the thickness of the outer layer is 210 μm or less, the manufacturing cost of the laminate sheet 55 for tube containers can be reduced, and moldability can be ensured when the head member is molded by a compression molding method.
The inner layer 2 is preferably, for example, 50 μm or more and 100 μm or less. When the thickness of the inner layer is 50 μm or more, the sealing strength can be ensured. Also, when the thickness of the inner layer is 100 μm, the manufacturing cost of the laminate sheet 55 for tube containers can be reduced.

Examples of methods for heat sealing (welding) when manufacturing the cylindrical body of the tube container 10 include bar sealing, rotary roll sealing, belt sealing, impulse sealing, high frequency sealing, ultrasonic sealing, and flame sealing.

In addition, in this embodiment, the head member 40 and the cylindrical body 50 of the tube container 10 are joined by thermal welding when the head member 40 is molded by compression molding. However, this is not limited to this, and the head member and the cylindrical body of the tube container 10 may also be joined by injection molding.

Next, referring to FIG. 8, a method for manufacturing the above-mentioned tube container 10 using compression molding will be described.

As shown in FIG. 8(a), this cylindrical body (body 50) is inserted into a mandrel 72, and a die 71 for compression molding the head member 40 is attached to one end of the mandrel 72. That is, the cylindrical body (body 50), which has been molded into a cylindrical shape in advance, is inserted into the mandrel 72, whose tip serves as a core for compression molding the head member 40, and then advanced to a predetermined position into the cavity of the die 71 for molding the head member 40.

Then, the head member 40 is compression molded by supplying molten resin from a resin supply device into the mold 71. In this case, the head member 40 is molded by inserting the opening of one end of the body portion 50 into the mold 71, and at the same time, the cylindrical body portion 50 is fused integrally to the head member 40. The integrated head member 40 and body portion 50 are then removed from the mold 71 and mandrel 72, yielding a tube container 10 as shown in FIG. 8(b).

The cap 20 is also produced by injection molding using an injection molding machine (not shown). The cap 20 is then screwed onto the mouth of the head member 40 of the tube container 10, thereby obtaining the tube container 10.

In the present disclosure, the tube container 10 manufactured as described above can be filled with the contents to be packed through the opening at the bottom end, and then the opening can be heat sealed to form a bottom weld, thereby manufacturing a tube package (packaged product).

In the above, examples of contents to be filled and packaged include toothpaste, cosmetics, hair dye, glue, mustard greens, wasabi paste, cream, paint, ointment, medicines, and others.

When the tube container 10A filled with contents is to be disposed of after use, by bringing the upper body 50a and the lower body 50b (laminated portions of the outer layer 1 and the inner layer 2) closer to each other (pushing one toward the other), the inner layer 2 sandwiched between the upper body 50a and the lower body 50b of the tube container 10B can be deformed. This reduces the distance between the end faces of the upper body 50a and the lower body 50b, thereby reducing the volume of waste from the tube container 10B.

Next, we will explain a specific example of the above embodiment.

Example 1
First, a beautiful pattern layer was formed on the inner surface of a biaxially oriented polyethylene terephthalate film (thickness 12 μm) for the base layer 58 using a polyurethane gravure ink.

Next, 4 g/m2 of a polyurethane-based adhesive for dry lamination (a two-component curing urethane adhesive with a base agent: polyester resin and a curing agent: aliphatic polyisocyanate) was applied as a first adhesive layer 57a to the outer surface of the biaxially oriented polyethylene terephthalate film by a ^roll coating method, and after drying, a linear low density polyethylene (LLDPE) film having a thickness of 130 μm was laminated and bonded as a first sealant layer 56.

Next, 4 g/ ^m2 of a polyurethane-based adhesive for dry lamination was applied as a second adhesive layer 57b to the inner surface on the base layer 58 side of the laminated film obtained above, and then dried. After that, a 9 μm aluminum foil for a light-shielding barrier layer 60 was laminated by dry lamination to obtain a base sheet for the outer layer 1.

(Outer layer) First sealant 56 LLDPE film (130 μm) / Adhesive layer DL adhesive / Base layer 58 Biaxially oriented polyethylene terephthalate film (12 μm) / Picture print layer / Adhesive layer DL adhesive / Light-shielding barrier layer 60 Aluminum foil 9 μm

On the other hand, a silicone compound coating agent ("Polycoat P-91" manufactured by DIC Corporation) for the easy peeling layer 52 was applied to the surface of a 130 μm-thick linear low density polyethylene (LLDPE) film for the second sealant layer 59 in an amount of 4 g/ ^m2 by roll coating, followed by drying to obtain a raw sheet for the inner layer 2. The layer structure is as follows.

(Inner layer) Easy-peel layer 52 Silicone compound coating layer / Second sealant layer 59 LLDPE film (180 μm)

The aluminum foil surface of the obtained outer layer 1 and the surface of the easily peelable inner layer 52 were stacked facing each other, and then thermally laminated using a heated roll with a metal plate and a silicone rubber sheet, both of which had been preheated to a temperature of 140°C, under conditions of 140°C, 0.15 MPa, and a time of 2.0 seconds.

Using the laminated sheet 55 for tube containers obtained above, the area where the outer layer 1 is to be peeled off was irradiated with carbon dioxide laser light from the side that would become the outside of the container, forming two parallel dotted first and second cut lines 13a and 13b (with a 0.7 mm spacing between each cut and a 0.7 mm joint) at a portion (first cut line 13a) 5.0 mm below the position that will be joined to the head member of the body of the tube container, and at a portion (second cut line 13b) 10.0 mm above the position that will be the bottom side of the body. The layer structure is as follows. The first cut line 13a and the second cut line 13b were formed from the side that would become the outside of the container to a depth that penetrated the base layer. The layer structure of the laminated sheet 55 for tube containers is as follows.

(Outer surface) First sealant layer 56 LLDPE film (130 μm) / Adhesive layer DL adhesive / Base layer 58 Biaxially oriented polyethylene terephthalate film (12 μm) / Pattern printed layer / Adhesive layer DL adhesive / Light-shielding barrier layer 60 Aluminum foil 9 μm / Easy-peel layer 52 Silicone-based compound coating layer / Second sealant layer 59 LLDPE film (180 μm) (Inner surface)

Next, the laminate sheet 55 for tube containers was used to overlap one side edge with the other side edge using a mandrel to form a tube shape, and the back layer and front layer of the laminate sheet 55 for tube containers at the overlapping portion were welded by a thermal welding method to obtain the body 50.

Then, a head member with a check valve was integrally molded into this cylindrical molded body by insert injection molding to obtain the tube container 10 according to Example 1 of the present disclosure. High density polyethylene (HDPE) was used as the material for the head member.

In this manner, the tube container 10 was produced.

In parallel with the production of the tube container 10, the cap 20 was produced by injection molding. The resulting cap 20 was then screwed onto the mouth of the head member 40 of the tube container to produce the tube container 10 with the cap.

Even when filled with 180 g of hair treatment, the outer layer 1 and inner layer 2 of this capped tube container 10 do not peel off during processing of the laminated sheet 55 for the tube container, and after using the tube container 10A filled with the content C, the first cut line 13a and the second cut line 13b can be cut off, shortening the distance between the end faces of the upper body portion 50a and the lower body portion 50b, thereby reducing the volume of waste in the tube container 10A.

Example 2
A silicone compound coating agent ("Polycoat P-91" manufactured by DIC Corporation) was applied by roll coating to the surface of a 30 μm-thick linear low-density polyethylene film for the intermediate layer 61 at 4 g/m ² for the easy peeling layer 52, and dried. A laminate sheet 55 for tube containers was obtained in the same manner as in Example 1, except that the oil barrier layer 62 was changed to an ethylene-vinyl alcohol copolymer of 15 μm, and a capped tube container 10A (Example 2) filled with contents was produced. Then, peeling at the joint between the outer layer 1 and the inner layer 2 was confirmed in the same manner as in Example 1. The layer structure and thickness of each layer of this laminate sheet 55 for tube containers are as follows.

(Outer surface) First sealant layer 56 LLDPE film (130 μm) / Adhesive layer DL adhesive / Base layer 58 Biaxially oriented polyethylene terephthalate film (12 μm) / Picture print layer / Adhesive layer DL adhesive / Light-shielding barrier layer 60 Aluminum foil 9 μm / Easy-peel layer 52 Silicone compound coating layer / Intermediate layer 61 Linear low-density polyethylene film (30 μm) / Oil barrier layer 62 Ethylene-vinyl alcohol copolymer (15 μm) / Second sealant layer 59 LLDPE film (180 μm) (Inner surface)

Example 3
Except for providing the first and second cut lines 13a and 13b of the half cut, a laminate sheet 55 for a tube container was obtained in the same manner as in Example 1, and a tube container 10A with a cap filled with a content (Example 3) was produced. Then, in the same manner as in Example 1, peeling at the joint between the outer layer 1 and the inner layer 2 was confirmed.

(Comparative Example 1)
A capped tube container (Comparative Example 1) filled with contents was produced in the same manner as in Example 1, except that an aluminum-deposited PET film (12 μm) was used for the light-shielding barrier layer instead of aluminum foil, and 4 g/m ² of polyurethane adhesive for dry lamination (main agent: polyester resin, hardener: two-liquid curing urethane adhesive of aliphatic polyisocyanate) was applied between the second sealant layer and the light-shielding barrier layer, and between the outer layer and the inner layer, dried, and then bonded together. Then, peeling at the joint between the outer layer and the inner layer was confirmed in the same manner as in Example 1. The layer structure and thickness of each layer of this laminate sheet 55 for tube containers are as follows.

(Outer surface) First sealant LLDPE film (130 μm) / Adhesive layer DL adhesive / Base layer biaxially oriented polyethylene terephthalate film (12 μm) / Picture print layer / Adhesive layer DL adhesive / Light-shielding barrier layer aluminum-deposited PET film (12 μm) / Adhesive layer DL adhesive / Second sealant layer LLDPE film (180 μm) (Inner surface)

[Peel strength test 1]
The laminate sheet 55 for tube containers in the example obtained above was cut into strips of 15 mm x 100 mm, and the laminate strength between the outer layer 1 and the inner layer 2 was measured by T-peel using a tensile tester in accordance with JIS K6854-2. That is, the non-laminated part was opened and held in a T-shape, and the tensile force applied to the laminated part when it peeled off was taken as the laminate strength. The peel speed was 50 mm/min, and the average value of the tensile stress in the stable region was measured (measurements were repeated 3 times). The results are shown in Table 1.

As can be seen from Table 1, the laminated sheets 55 for tube containers in Examples 1 to 3 peeled between the outer layer 1 and the inner layer 2 with a tensile strength of 0.7 N/15 mm to 1.2 N/15 mm, while the laminated sheet 55 for tube containers in Comparative Example 1 peeled between the outer layer 1 and the inner layer 2 with a tensile strength of 6.0 N/15 mm.

[Peel Strength Test 2]
In addition, the outer sealant layer and the inner sealant layer were overlapped on the side portion of the tube container laminate sheet 55 in Examples 1 to 3 and Comparative Example 1 so that the outer first sealant layer of the tube container laminate sheet 55 was on the outside, and the opposing surfaces were impulse sealed to produce a cylindrical body portion (body portion 50).
Next, high density polyethylene was compression molded into one opening of the cylindrical body (body 50), and the head including the shoulder and mouth was joined to produce the tube container 10 of the present invention.
Next, 150 g of toothpaste was filled into each tube container from the bottom, and the bottom seal portion 17 was then heat sealed to produce a tube container A filled with the contents.
After the content C was extruded from the tube container 10A, the outer layer 1 was peeled off by hand along the first cut line 13a and the second cut line 13b. The results of evaluation according to the following evaluation criteria are shown in Table 2.

[Evaluation Criteria]
◯: The outer layer 1 can be peeled off by hand. ×: The outer layer 1 cannot be peeled off by hand.

As can be seen from Table 2, in the tube containers 10 of Examples 1 to 3, the outer layer 1 and the inner layer 2 easily peeled off from each other, but in the tube container 10 of Comparative Example 1, the outer layer 1 and the inner layer 2 did not peel off from each other.

1 Outer layer 2 Inner layer 2a Ruled line (groove)
10 Tube container 10A Tube container filled with contents 10B Tube container with part of the outer layer cut off 11 Mouth portion 12 Shoulder portion 13 Cut line 13a First cut line (cut line)
13b Second cut line (cut line)
Reference Signs List 14 Notch 16 Opening 17 Bottom seal portion 18 Side seal portion 20 Cap 40 Head member 50 Body portion 52 Easy peel layer 55 Laminate sheet for tube container 56 First sealant layer 57a First adhesive layer 57b Second adhesive layer 58 Base layer 59 Second sealant layer 60 Light-shielding barrier layer 61 Intermediate layer 62 Oil barrier layer 71 Mold 72 Mandrel

Claims (4)

a cylindrical body member formed by overlapping and joining opposing ends of the laminate sheet for tube containers to each other;
a head member joined to one end of the cylindrical body member,
The head member is a tube container including a shoulder portion and a mouth portion,
The laminate sheet for tube containers includes an outer layer and an inner layer arranged in this order from the outer surface to the inner surface,
The outer layer includes, in order from the outer surface, a first sealant layer and a base layer,
the outer layer includes a score line and the inner layer includes a second sealant layer;
The tube container according to claim 1, wherein the inner layer has an easily peelable layer on a surface in contact with the outer layer. The tube container according to claim 1, characterized in that the outer layer further has a light-shielding barrier layer on the surface side in contact with the inner layer. The tube container according to claim 1 or 2, characterized in that the inner layer further has an oil barrier layer. 4. The tube container according to claim 1 , wherein the base layer is a biaxially oriented film.