JP7494531B2 - Laminated body of tube container and tube container - Google Patents

Description

The present invention relates to a laminate for a tube container that allows the body to be easily disassembled and makes it easy to use the contents remaining after use, and to a tube container using such a laminate.

Conventionally, laminates used in tube containers have a structure in which a base layer is provided between sealant layers used on the outer and inner surfaces. A resin film is used as the base layer in order to meet mechanical, physical, chemical, and other suitability requirements (see Patent Document 1).

JP 2005-178851 A

On the other hand, with tube containers, it is possible that not all of the contents can be dispensed, with some remaining content. In such cases, it may be desirable to break the body of the tube container to remove the contents. However, with the above-mentioned conventional tube containers, the laminate that constitutes the body is very strong, making it difficult to break, and so the body is broken using a tool such as scissors.

The present invention aims to provide a laminate for a tube container that allows the body to be easily broken to facilitate use of the remaining contents, and a tube container that uses such a laminate.

In order to solve the above problems, the present invention provides
A laminate comprising at least a first sealant layer, a base layer, and a second sealant layer laminated in this order,
The laminate has a tear strength of 4 N or more and 16 N or less.

The laminate of the present invention is
The substrate layer is characterized in that it is made of paper.

The laminate of the present invention is
The sealant further comprises a metal foil between the base layer and the second sealant layer.

The laminate of the present invention is
The paper used for the paper base layer has a basis weight of 50 g/m ² or more and 150 g/m ² or less.

The laminate of the present invention is
At least one of the first sealant layer and the second sealant layer contains a plant-derived resin.

The present invention also provides a method for producing a method for manufacturing a semiconductor device comprising the steps of:
The present invention provides a tube container, characterized in that the laminate is used as a body part.

The present invention provides a laminate for a tube container that allows easy use of remaining contents, and a tube container using such a laminate.

FIG. 2 is a front view (partial cross-sectional view) of the tube container with the cap attached. FIG. 2 is a front view (partial cross-sectional view) of a packaged product of a tube container containing a content. FIG. 2 is a diagram showing a cylindrical body portion of a tube container according to one embodiment of the present invention. 1 is a cross-sectional view of a laminate of a body portion of a tube container according to one embodiment of the present invention. FIG. 1 shows a tear strength test.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.
However, the present invention is not limited to these specifically exemplified forms or various specifically described structures. In each drawing, the size and ratio of the members may be changed or exaggerated for ease of understanding. In addition, for ease of viewing, parts that are unnecessary for explanation or repeated reference symbols may be omitted.

In this specification, "outer surface" and "inner surface" refer to the "outer surface" and "inner surface" when the tube container 30 is produced using the laminate 10. Additionally, "upper side" and "lower side" refer to the side of the mouth 36 when the tube container 30 is held with the mouth 36 and the cap 20 facing upward, and "lower side" refers to the opposite side of the mouth 36 (the 34B side in FIG. 1 and the 39 side in FIG. 2).

Figure 1 is a partial cross-sectional view of a tube container according to this embodiment with a cap attached. Figure 2 is a partial cross-sectional view of a packaged product of a tube container containing a content. As shown in Figure 1, a tube container 30 according to this embodiment includes a body 31 made of a laminate 10, and a head molded body 37 made by providing a synthetic resin to the body 31 by a method such as compression molding or injection molding. The head molded body 37 further includes a shoulder portion 35 and a mouth portion 36. A cap 20 is attached to the mouth portion 36 of the tube container 30.

The tube container 30 has a head molded body 37 consisting of a cylindrical mouth 36 including a discharge opening, and a truncated cylindrical shoulder 35 connected to the mouth 36 and expanding in circumference downward. In FIG. 1, the right half of the head molded body 37 shows its front, and the left half shows a cross section parallel to the front through its radial center. The hatched portion in the left half of FIG. 1 shows the actual head molded body 37, and the blank portion is a cavity. The shoulder 35 is configured, for example, in a truncated cone shape that expands radially outward from the tube container 30 as it moves away from the mouth 36. For example, the shoulder 35 has an inclination of 30 degrees with respect to the horizontal. The shoulder 35 is connected to the body 31 on the lower side.

The approximately cylindrical mouth 36 has a helical protrusion on the outer surface that functions as a screw thread. The inner peripheral surface of the mouth 36 defines an opening. The opening of the mouth 36 serves as a discharge port for discharging the contents. The contents contained in the body 31 are discharged from the tube container 30 by passing through the opening.

The head molding 37 has the above-mentioned structure, so it can be attached and detached by screwing it into the cap 20, which has a threaded groove on the inside.

The body 31 is a film-like laminate formed into a cylindrical shape. One end of the cylindrical body 31 is joined to the shoulder 35. Meanwhile, the other end of the body 31 is sealed by a bottom seal 39 formed by overlapping and joining the inner surface of the cylindrical body 31 (see FIG. 2). The bottom seal 39 may be joined after the body 31 is filled with the contents. The body 31 of the tube container 30, in particular, may be configured to have flexibility (softness, squeezability) that allows the desired amount of contents to be easily pushed out even if the contents have some viscosity. The dimensions of the body 31 may be designed appropriately depending on the type of contents, and may be, for example, 50 mm in diameter.

The tube container 30 having the above-mentioned configuration is obtained through the following manufacturing process.
First, as shown in FIG. 3, a pair of bonding ends (hereinafter sometimes referred to as both ends) 33A, 33B of the laminate 10 are overlapped using the laminate 10, and the outer and inner surfaces of the overlapped portions are heat-sealed and bonded together to form a body bonding portion 32, thereby producing a cylindrical body portion 31.

Heat sealing can be performed by any of the conventional methods known in the art, such as bar sealing, rotary roll sealing, belt sealing, impulse sealing, high frequency sealing, ultrasonic sealing, and flame sealing.

Next, the cylindrical body 31 shown in FIG. 3 is placed in a mold (not shown), and the head molded body 37 (shoulder 35, mouth 36) shown in FIG. 1 is formed at one opening (upper side) 34A of the body 31 by a method such as compression molding or injection molding. In this way, the head molded body 37 (shoulder 35, mouth 36) is molded integrally with one opening (upper side) 34A of the body 31, and the tube container 30 is produced. Then, the cap 20 is attached to the mouth 36 side of the tube container 30.

Next, an appropriate amount of contents, such as hand cream, sunscreen, hair styling agent, toothpaste, or other contents, is filled into the other opening (lower side) 34B of the cylindrical body 31 of the tube container 30 shown in FIG. 1. The opening (lower side) 34B is then welded to form the bottom seal portion 39 shown in FIG. 2. As a result, a packaged product 30A is obtained, including the tube container 30 filled and packaged with the contents.

The details of the head molded body 37 will be explained further. The head molded body 37 is made of a material that can be molded so that the mouth 36 and shoulder 35 have an appropriate hardness, has high adhesion to the material of the body 31, does not affect the quality of the contents, and does not cause hygienic problems even if it comes into contact with the contents. As such a material, a thermoplastic resin is used for the head molded body 37, and more specifically, high density polyethylene (HDPE) is used.

Furthermore, the head molded body 37 may be made of polyolefin resins such as low-density polyethylene, linear low-density polyethylene, medium-density polyethylene, polypropylene (homopolypropylene, block polypropylene, random polypropylene), copolymers of olefins with copolymerizable monomers such as vinyl monomers, acrylic monomers, unsaturated carboxylic acids, or blends thereof, and resins in which the above-mentioned resins are blended with high-density polyethylene. Furthermore, from the viewpoint of heat resistance and thermal adhesion to the body 31, it is preferable to use a resin in which linear low-density polyethylene is blended with high-density polyethylene for the head molded body 37. Furthermore, a truncated cone-shaped cylinder may be laminated as a barrier material to prevent the permeation of gases such as oxygen, particularly on the shoulder portion 35 of the head molded body 37. The shoulder portion 35 may contain a plant-derived resin.

The high-density polyethylene used to form the shoulder 35 of the head molded body 37 may be derived from fossil raw materials, but biomass-derived high-density polyethylene, known as a carbon-neutral material, may also be used to reduce the environmental impact. Since the head and cap make up a large mass proportion of the tube container, by molding the head molded body 37 using biomass-derived high-density polyethylene, the amount of fossil raw materials used for the entire tube container can be reduced, thereby reducing the environmental impact. In addition, the head molded body 37 of the tube container 30 is comparable in terms of physical properties such as mechanical properties to heads manufactured from materials obtained from conventional fossil raw materials, so it can replace conventional heads.

From the viewpoint of reducing the environmental load, it is preferable to use only biomass-derived polyethylene, but a blend of fossil-derived polyethylene and biomass-derived polyethylene may be used in consideration of production costs, etc. Here, biomass-derived polyethylene is a monomer polymer containing biomass-derived ethylene. Since biomass-derived ethylene is used as the raw material monomer, the polymerized polyethylene is derived from biomass. The content of biomass-derived ethylene in the raw material monomer does not need to be 100% by mass, and is, for example, preferably 10% by mass or more, more preferably 30% by mass or more. The raw material monomer may contain fossil-derived ethylene, or may contain α-olefin monomers such as butylene, hexene, and octene. Even in such a case, the obtained polymer is called biomass polyethylene. When using biomass-derived polyethylene, it may contain two or more polyolefins with different biomass degrees. In addition, when blending fossil-derived polyethylene and biomass-derived polyethylene, the mixing method is not particularly limited, and dry blending or melt blending may be used. Furthermore, when the two are mixed, the mixing ratio of fossil-derived polyethylene to biomass-derived polyethylene is preferably 1:9 to 9:1 by mass, and more preferably 2:8 to 8:2.

For example, biomass-derived ethylene can be produced using biomass-derived ethanol as a raw material. In particular, it is preferable to use biomass-derived fermented ethanol obtained from plant raw materials. In other words, it is preferable to use a plant-derived resin. The plant raw material is not particularly limited, and any conventionally known plant can be used. Examples include corn, sugar cane, beet, and manioc.

In the present invention, fermented ethanol derived from biomass refers to ethanol produced by contacting a culture solution containing a carbon source obtained from a plant raw material with an ethanol-producing microorganism or a product derived from its crushed material, and then purifying the ethanol. Conventionally known methods such as distillation, membrane separation, and extraction can be used to purify ethanol from the culture solution. For example, methods include adding benzene, cyclohexane, etc., and performing azeotropic distillation, or removing water by membrane separation, etc. can be used.

The thickness of the head molding 37 in which such resins are used is preferably 0.5 mm or more and 2.0 mm or less. In this embodiment, the head molding 37 is produced by compression molding. Therefore, in the head molding 37, which is a compression molded product, it is possible to prevent the occurrence of depressions, so-called sink marks, caused by shrinkage during molding, even in thick parts such as the top surface. Furthermore, it is possible to reduce waste of material such as in the gate portion. The head molding 37 may also be produced by injection molding.

Next, the laminate 10 forming the cylindrical body 31 will be described with reference to FIG. 4. The laminate 10 forming the body 31 of the tube container 30 is a laminate having a first sealant layer 12, a paper base layer 13, an adhesive layer 16, a barrier layer 14, and a second sealant layer 15, which are arranged in this order from the outer surface to the inner surface, as shown in FIG. 4. The thicknesses of the first sealant layer 12, the paper base layer 13, the adhesive layer 16, the barrier layer 14, and the second sealant layer 15 are different in reality, but in FIG. 4, they are shown as the same thickness for convenience. In addition, the adhesive layer formed during adhesion by dry lamination is thinner than the other layers, so it is not shown. When forming the cylindrical body 31, the outer surface of the first sealant layer 12 and the inner surface of the second sealant layer 15 are directly bonded at one end of the laminate 10. Although materials other than paper can be used as the base layer, in this embodiment, the paper base layer 13 made of paper is used as the base layer.

An outer surface printed portion 13A containing a desired pattern is formed on the outer surface of the paper base layer 13 using printing ink. If a see-through material other than paper is used as the base layer, an inner surface printed portion may be formed on the inner surface of the base layer using printing ink. Also, an outer surface printed portion containing a desired pattern may be formed on the outer surface of the first sealant layer 12 using printing ink.

The first sealant layer 12 and the paper base layer 13 are joined by extrusion lamination. The paper base layer 13 and the barrier layer 14 are joined by an adhesive layer 16 formed by extrusion lamination. The barrier layer 14 and the second sealant layer 15 are joined by extrusion lamination (an adhesive layer similar to the adhesive layer 16: not shown) or dry lamination. When the barrier layer 14 and the second sealant layer 15 are laminated between layers by extrusion lamination, the barrier layer 14 and the second sealant layer 15 can be made compatible with the extruded resin to maintain content resistance.

When two layers are bonded by dry lamination, an adhesive layer can be formed by applying an adhesive to the surface of the layer to be laminated and drying it. As the adhesive, for example, one-component or two-component curing or non-curing vinyl, (meth)acrylic, polyamide, polyester, polyether, polyurethane, epoxy, rubber, and other solvent-based, water-based, or emulsion-based adhesives can be used. As a two-component curing adhesive, a cured product of polyol and an isocyanate compound can be used. As a coating method for the above-mentioned laminating adhesive, for example, the direct gravure roll coating method, gravure roll coating method, kiss coating method, reverse roll coating method, Fountain method, transfer roll coating method, and other methods can be used to apply it to the coating surface of the layer that constitutes the laminate.

The thermoplastic resin used in the extrusion laminate may be a polyethylene resin, a polypropylene resin, or a cyclic polyolefin resin, or a copolymer resin, modified resin, or mixture (including alloy) containing these resins as the main component. Examples of the polyolefin resin include the above-mentioned polyethylene, polypropylene (PP), ethylene-α-olefin copolymer polymerized using a metallocene catalyst, ethylene-polypropylene random or block copolymer, ethylene-vinyl acetate copolymer (EVA), ethylene-acrylic acid copolymer (EAA), ethylene-ethyl acrylate copolymer (EEA), ethylene-methacrylic acid copolymer (EMAA), ethylene-methyl methacrylate copolymer (EMMA), ethylene-maleic acid copolymer, ionomer resin, and acid-modified polyolefin resin modified with unsaturated carboxylic acid such as acrylic acid, methacrylic acid, maleic acid, maleic anhydride, fumaric acid, and itaconic acid to improve adhesion between layers. In addition, resins obtained by graft-polymerizing or copolymerizing unsaturated carboxylic acids, unsaturated carboxylic anhydrides, and ester monomers can be used as polyolefin resins. These materials can be used alone or in combination of two or more. Examples of cyclic polyolefin-based resins that can be used include cyclic polyolefins such as ethylene-propylene copolymers, polymethylpentene, polybutene, and polynorbornene. These resins can be used alone or in combination of two or more. The above-mentioned polyethylene-based resins can be further improved in biomass content by using the above-mentioned biomass-derived ethylene as a monomer unit.

When laminating the adhesive layer 16, which is an adhesive resin layer, by extrusion lamination, an anchor coat (AC) layer may be provided on the surface of the layer to be laminated, which is formed by applying and drying an anchor coat agent. Examples of anchor coat agents include anchor coat agents made of any resin with a heat resistance temperature of 135°C or higher, such as vinyl modified resin, epoxy resin, urethane resin, polyester resin, polyethyleneimine, etc., and in particular, an anchor coat agent that is a hardened product of a polyacrylic or polymethacrylic resin (polyol) having two or more hydroxyl groups in its structure and an isocyanate compound as a hardener can be preferably used. In addition, a silane coupling agent may be used in combination with this as an additive, and nitrocellulose may also be used in combination to increase heat resistance.

The anchor coat layer after drying has a thickness of 0.1 μm to 1 μm, preferably 0.3 μm to 0.5 μm. The adhesive layer after drying preferably has a thickness of 1 μm to 10 μm, preferably 2 μm to 5 μm. The adhesive layer 16, which is an adhesive resin layer, preferably has a thickness of 5 μm to 50 μm, preferably 10 μm to 30 μm.

Next, the materials of each part constituting the laminate 10 of the cylindrical body portion 31 will be described.
The first sealant layer 12 and the second sealant layer 15 may include, for example, polyethylene (PE). Specifically, the first sealant layer 12 and the second sealant layer 15 may be made of the following materials:

The first sealant layer 12 and the second sealant layer 15 may be made of any material that can be melted and fused to each other by heat. For example, low-density polyethylene (LDPE), medium-density polyethylene (MDPE), high-density polyethylene (HDPE), linear low-density polyethylene (LLDPE), 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 may be used.

The paper base layer 13 can be made of unbleached kraft paper, bleached kraft paper, cup base paper, or parchment paper, and the paper base layer 13 can be printed to provide an outer surface printed portion 13A made of printing ink. The paper base layer 13 also maintains the rigidity of the tube container.

When a material other than the paper base layer 13 is used as the base layer, a polyolefin film such as polyethylene (PE) or polypropylene (PP) can be used. As the polyethylene (PE), low density polyethylene (LDPE), medium density polyethylene (MDPE), high density polyethylene (HDPE), linear low density polyethylene (LLDPE), etc. can be used. The same polyolefin film as that used as the first sealant layer 12 and the second sealant layer 15 may be used.

A polyethylene terephthalate (hereinafter abbreviated as PET) layer can be used as the substrate layer, and an inner printed portion made of printing ink can be provided on the PET layer by printing on the PET layer. Also, instead of using a PET layer as the substrate layer, a nylon layer can be used. When a nylon layer is used, it often has superior mechanical strength to a PET layer.

The barrier layer 14 is appropriately selected depending on the required functions, such as water vapor and other gas barrier properties, and an ethylene-vinyl alcohol copolymer film, a vapor deposition film, or a metal foil can be used. When a metal foil is used as the barrier layer 14, various metal foils having barrier properties, such as copper and tin, can be used, but it is preferable to use aluminum foil.

When a vapor-deposited film is used as the barrier layer 14, the base film of the vapor-deposited film can be polyethylene terephthalate (PET), nylon, or the like. The metal to be vapor-deposited onto the base film can be any of various materials commonly used in metal vapor deposition, such as copper or tin. It is also possible to provide a vapor-deposited film of a metal oxide, such as aluminum oxide, or an inorganic oxide, such as silicon oxide.

When a vapor-deposited film is used as the barrier layer 14, a PET layer having a metal vapor-deposited film on at least one side and gas barrier properties may be used, or a nylon layer having a metal vapor-deposited film on at least one side and gas barrier properties may be used.

A PET layer having a silica vapor deposition film on at least one side and gas barrier properties may also be used, or a nylon layer having a silica vapor deposition film on at least one side and gas barrier properties may also be used.

A PET layer having an aluminum oxide vapor deposition film on at least one side and gas barrier properties may also be used, or a nylon layer having an aluminum oxide vapor deposition film on at least one side and gas barrier properties may also be used.

When a nylon layer is used, the mechanical strength is often superior to that of a PET layer. In addition, films with various deposition films have better gas barrier properties than the base film. Furthermore, a gas barrier coating film may be provided on the deposition film. This suppresses the permeation of oxygen and water vapor, and by providing it adjacent to the deposition film, the occurrence of cracks in the deposition film can be effectively prevented. The gas barrier coating film is a gas barrier coating film containing at least one resin composition such as a hydrolyzate of a metal alkoxide or a hydrolyzed condensate of a metal alkoxide obtained by polycondensing a mixture of a metal alkoxide and a water-soluble polymer by the sol-gel method in the presence of a sol-gel catalyst, water, an organic solvent, etc.

The resins described above as materials used for the first sealant layer 12 and the second sealant layer 15 may be not only those derived from fossil raw materials, but also biomass-derived resins. For example, in addition to the biomass-derived polyethylene resin described above, biomass polyesters using biomass-derived ethylene glycol as a diol component as described in JP 2012-116082 A, polylactic acid resins, cellophane, starch, cellulose, etc. may be used. As the biomass-derived resin, it is preferable to use a plant-derived resin. Furthermore, a multi-layer sealant containing a gas barrier resin such as an ethylene-vinyl alcohol copolymer may be used.

The outer surface printing part 13A provided on the outer surface of the paper base layer 13 is printed by gravure printing or offset printing on the paper base layer 13, so it is possible to print with excellent cosmetic properties. In addition, in the case of a paper base layer that is less smooth, the smoothness can be improved by covering the surface of the paper base layer with polyethylene. It is possible to impart design properties by performing flexographic printing or digital printing on top of that.

Next, a method for manufacturing the laminate 10 of the cylindrical body portion 31 will be described with reference to FIG.
First, printing is applied to the outer surface of the paper base layer 13 to provide an outer surface printed portion 13A made of printing ink on the outer surface of the paper base layer 13.

Next, the first sealant layer 12 is laminated onto the outer surface of the paper base layer 13 by extrusion lamination. Next, the barrier layer 14 is laminated onto the inner surface of the paper base layer 13 by extrusion lamination. This forms an adhesive layer 16 between the paper base layer 13 and the barrier layer 14. Next, the second sealant layer 15 is joined to the inner surface of the barrier layer 14 by extrusion lamination or dry lamination.

In the manner described above, the laminate 10 of the body portion 31 is obtained. However, the manufacturing method is not limited to the above as long as the desired laminate 10 can be obtained.

The laminate 10 of the body 31 thus obtained is rolled into a cylindrical shape, and the two ends 33A, 33B are overlapped as described above. The outer and inner surfaces of the laminate 10 are heat sealed at the two ends 33A, 33B to form the body attachment section 32, and the tubular body 31 is produced. In this case, the first sealant layer 12 provided on the outer side of the laminate 10 and the second sealant layer 15 provided on the inner side are melted and joined to obtain the tubular body 31.

In the above, the body attachment portion 32 is formed by overlapping, but the end faces of both ends 33A, 33B may be butted together and joined. Furthermore, the joint line formed by butting together as described above may be protected by attaching a film to the inner or outer surface of the cylindrical body portion 31. The inner end 33B may also be processed to protect the end face. For example, it may be protected by taping, or the end 33B may be bent toward the outside of the container (hemming).

Next, the opening (upper side) 34A of the cylindrical body 31 shown in FIG. 3 is inserted into a mold (not shown), and a shoulder 35 and a mouth 36 are formed in the opening (upper side) 34A of the cylindrical body 31 using a method such as compression molding or injection molding, thereby obtaining the tube container 30 (see FIG. 1).

Next, the cap 20 is attached to the mouth 36 of the tube container 30 manufactured as described above, and a number of the tube containers 30 with the cap 20 attached are stored together in a cardboard box. The multiple tube containers 30 with the cap 20 attached are then transported together in a cardboard box. At the destination, the tube containers 30 are filled with an appropriate amount of hand cream, sunscreen, hair styling agent, toothpaste, or other contents, and the opening (lower side) 34B is welded to form a bottom seal 39. This results in a packaged product 30A in which the contents are filled and packaged in the tube container 30.

Example 1
The base film for the first sealant layer 12 was a 60 μm thick LLDPE film, the paper substrate layer 13 was a 175 μm thick paper ("LRD base paper (basis weight 150 g/ ^m2 )" manufactured by Nippon Paper Industries Co., Ltd.), the adhesive layer 16 was a 20 μm thick ethylene-methacrylic acid copolymer resin layer (EMAA), the barrier layer 14 was a 12 μm thick silicon oxide vapor-deposited PET film, and the base film for the second sealant layer 15 was an 80 μm thick LLDPE film.

Specifically, first, an outer printed portion 13A was formed on the outer surface of a 175 μm-thick paper that would become the paper base layer 13. Next, a 12 μm-thick silicon oxide vapor-deposited PET film that would become the barrier layer 14 was bonded by extrusion lamination to the inner surface of the 175 μm-thick paper that would become the paper base layer 13, with a 20 μm-thick adhesive layer 16 of EMAA, a thermoplastic resin. The silicon oxide vapor-deposited PET film used here has a gas barrier coating film on the silicon oxide vapor-deposited film to prevent a decrease in barrier properties even when the tube container (laminated tube) is bent when in use, and further has a vapor-deposited film of aluminum oxide that has good adhesion to EMAA.

Next, an anchor coat layer was formed on the inner surface of a 12 μm thick silicon oxide vapor-deposited PET film that would become the barrier layer 14, and an 80 μm thick LLDPE film that would become the second sealant layer 15 was attached by extrusion lamination using a 20 μm thick adhesive layer of polyethylene (LDPE), a thermoplastic resin.

Next, the first sealant layer 12 was laminated on the outer surface of the paper base layer 13 by extrusion lamination. Specifically, a 60 μm thick LLDPE film, which serves as the central base material of the first sealant layer 12, was bonded to the outer surface of the paper base layer 13 by extrusion lamination using LDPE, a thermoplastic resin, as an adhesive layer with a thickness of 15 μm. Furthermore, a 15 μm thick LDPE was laminated on the outer surface of the 60 μm thick LLDPE film, which serves as the first sealant layer 12, by extrusion lamination. The 15 μm thick LDPE, which serves as the outermost surface of the laminate, constitutes the first sealant layer 12.

As a result, a laminate 10 having a structure of LDPE 15 μm/LLDPE 60 μm/LDPE 15 μm/printing layer (ink)/paper 175 μm/EMAA 20 μm/silicon oxide vapor deposition PET 12 μm/AC/LDPE 20 μm/LLDPE film 80 μm was obtained. Furthermore, the laminate 10 was rolled into a cylindrical shape, and both ends 33A and 33B were overlapped as described above, and the outer surface and inner surface of the laminate 10 were heat-sealed at both ends 33A and 33B to form a body attachment portion 72, and a cylindrical body portion 31 was produced. The inner diameter of the cylindrical body portion 31, which specifies the tube shape, was set to 38 mm. Next, the opening 34A of the cylindrical body portion 31 was inserted into a mold, and the cylindrical body portion 31 was compression molded to form a shoulder portion 35 and a mouth portion 36 at the opening 34A of the cylindrical body portion 31. Then, 90 g of toothpaste paste (tooth powder) was filled into the other opening 34B of the cylindrical body 31. The opening 34B was then welded to form a bottom seal 39, producing a tube container 30 filled and packaged with the contents. The cap 20 was then attached to the tube container 30 by screwing the inner surface of the cap 20, which was made separately, into the screw structure on the outer surface of the mouth 36 of the tube container 30, to obtain a tube container 30 filled with the contents.

Example 2
The first sealant layer 12 was made of PE resin with a thickness of 60 μm, the paper base layer 13 was made of paper with a thickness of 120 μm (Nagoya Sarashi Ryuo (basis weight 100 g/ ^m2 ) manufactured by Daio Paper Co., Ltd.), the adhesive layer 16 was made of an ethylene-methacrylic acid copolymer resin layer (EMAA) with a thickness of 20 μm, the barrier layer 14 was made of a silicon oxide vapor-deposited PET film with a thickness of 12 μm, and the base film of the second sealant layer 15 was made of an LLDPE film with a thickness of 60 μm.

Specifically, first, an outer printed portion 13A was formed on the outer surface side of a 120 μm thick paper that would become the paper base layer 13. Next, a 12 μm thick silicon oxide vapor-deposited PET film that would become the barrier layer 14 was bonded to the inner surface of the 120 μm thick paper that would become the paper base layer 13 by extrusion lamination, with a 20 μm thick adhesive layer 16 of EMAA, a thermoplastic resin. Next, an anchor coat layer was formed on the inner surface side of the 12 μm thick silicon oxide vapor-deposited PET film that would become the barrier layer 14, and a 60 μm thick LLDPE film that would become the second sealant layer 15 was bonded to the inner surface of the 12 μm thick silicon oxide vapor-deposited PET film that would become the barrier layer 14 by extrusion lamination, with a 20 μm thick adhesive layer of polyethylene (PE), a thermoplastic resin. A second sealant layer with a thickness of 80 μm was obtained by extrusion lamination of the 20 μm thick LDPE and the 60 μm thick LLDPE film.

Next, the first sealant layer 12 was laminated by extrusion lamination on the outer surface of the paper base layer 13. Specifically, LDPE, a thermoplastic resin, was laminated to a thickness of 60 μm on the outer surface of the paper base layer 13 by extrusion lamination.

As a result, a laminate 10 was obtained with a structure of LDPE 60 μm/printing layer (ink)/paper 120 μm/EMAA 20 μm/silicon oxide vapor-deposited PET 12 μm/AC/LDPE 20 μm/LLDPE film 60 μm. The obtained laminate 10 was then used to obtain a tube container 30 filled with the contents in the same manner as in Example 1.

Example 3
The first sealant layer 12 was made of LDPE resin with a thickness of 60 μm, the paper base layer 13 was made of paper with a thickness of 70 μm (Snow Queen (basis weight 50 g/ ^m2 ) manufactured by Daio Paper Co., Ltd.), the adhesive layer 16 was made of ethylene-methacrylic acid copolymer resin layer (EMAA) with a thickness of 20 μm, the barrier layer 14 was made of aluminum foil (JIS 1N30) with a thickness of 9 μm, and the base film of the second sealant layer 15 was made of LLDPE film with a thickness of 60 μm.

Specifically, first, a 9 μm thick aluminum foil that would become the barrier layer 14 was bonded by extrusion lamination to the inner surface of a 70 μm thick paper that would become the paper base layer 13, with EMAA, a thermoplastic resin, as the adhesive layer 16 of 20 μm thick. Next, a 60 μm thick LLDPE film that would become the central base material of the second sealant layer 15 was bonded by extrusion lamination to the inner surface of the 9 μm thick aluminum foil that would become the barrier layer 14, with EMAA, a thermoplastic resin, as the adhesive layer of 20 μm thick. A second sealant layer of 80 μm thick was obtained from the 20 μm thick EMAA and the 60 μm thick LLDPE film.

Furthermore, the first sealant layer 12 was laminated on the outer surface of the paper base layer 13 by extrusion lamination. Specifically, LDPE, a thermoplastic resin, was laminated to a thickness of 60 μm on the outer surface of the paper base layer 13 by extrusion lamination. Furthermore, a printed portion was formed by flexographic printing on the outer surface side of the LDPE layer with a thickness of 60 μm that constitutes the first sealant layer 12.

As a result, a laminate 10 was obtained with a structure of printing/LDPE 60 μm/paper 70 μm/EMAA 20 μm/aluminum foil 9 μm/EMAA 20 μm/LLDPE 60 μm. The obtained laminate 10 was then used to obtain a tube container 30 filled with the contents in the same manner as in Example 1.

Example 4
A 90 μm-thick LLDPE film was used as the first sealant layer, a 12 μm-thick PET film was used as the base layer, a 12 μm-thick aluminum-deposited PET film was used as the barrier layer, and a 120 μm-thick LLDPE film was used as the second sealant layer. Compared to Examples 1 to 3, the major difference is that a PET film was used as the base layer instead of the paper base layer 13. In addition, a printed portion was provided on the inner surface side of the PET film as the base layer. In addition, each layer was bonded by dry lamination using an adhesive.

As a result, a laminate was obtained with a structure of LLDPE 90 μm/DL/PET 12 μm/printing layer (ink)/DL/aluminum-deposited PET 12 μm/DL/LLDPE 120 μm. The obtained laminate 10 was then used to obtain a tube container 30 filled with the contents in the same manner as in Example 1.

<Comparative Example 1>
A 150 μm-thick LLDPE film was used as the first sealant layer, a 12 μm-thick silicon oxide vapor-deposited PET film was used as the barrier layer, and a 150 μm-thick milky LLDPE film was used as the second sealant layer. A major difference from Examples 1 to 3 is that the paper base layer 13 was not provided. In Comparative Example 1, in order to increase the thickness of the entire laminate, the first sealant layer was made 150 μm thick and the second sealant layer was made 150 μm thick instead of the paper base layer. A printed portion was provided on the inner surface side of the silicon oxide vapor-deposited PET film as the barrier layer. All layers were bonded to each other by dry lamination using an adhesive.

As a result, a laminate was obtained with a structure of LLDPE 150 μm/DL/silicon oxide vapor-deposited PET 12 μm/printing layer (ink)/DL/milky white LLDPE 150 μm. The laminate of Comparative Example 1 does not have a paper substrate layer. The obtained laminate was used to obtain a tube container filled with the contents in the same manner as in Example 1.

<Comparative Example 2>
A 130 μm thick LLDPE film was used as the first sealant layer, a 12 μm thick PET film was used as the base layer, an aluminum foil with a thickness of 9 μm was used as the barrier layer, and a 130 μm thick LLDPE film was used as the second sealant layer. Compared with Examples 1 to 3, a major difference is that a PET film was used as the base layer instead of the paper base layer 13. Also, in Comparative Example 2, in order to increase the thickness of the entire laminate, the first sealant layer was made 130 μm and the second sealant layer was made 130 μm thick instead of the paper base layer. In addition, a printed portion was provided on the inner side of the PET film as the base layer. In addition, each layer was bonded by dry lamination using an adhesive.

As a result, a laminate was obtained with a structure of LLDPE 130 μm/DL/PET 12 μm/printing layer (ink)/DL/ALM 9 μm/DL/LLDPE 130 μm. The obtained laminate was then used to obtain a tube container filled with the contents in the same manner as in Example 1.

<Evaluation>
A total of six laminates, Examples 1 to 4 and Comparative Examples 1 and 2, were evaluated for tear strength. FIG. 5 is a diagram showing a tear strength test. FIG. 5(a) is a plan view of the test piece, and FIG. 5(b) is a diagram showing the state of the test using a tensile tester. A rectangular portion having a longitudinal direction along the vertical direction and the horizontal direction of each laminate obtained in Examples 1 to 4 and Comparative Examples 1 and 2 was cut out and used as a test piece S. As shown in FIG. 5(a), the test piece S has a cut K along its longitudinal direction. The length of the test piece S in the lateral direction (horizontal direction in FIG. 5(a)) was 30 mm, and the length of the test piece S in the longitudinal direction (vertical direction in FIG. 5(a)) was 110 mm. The cut K is formed over 50 mm in the center of the lateral direction of the test piece S. The up-down direction and the left-right direction of the test piece S correspond to the transverse direction (TD) and the machine direction (MD), respectively.

As shown in FIG. 5(b), the test piece S was pulled by a pair of chucks 40, 40 on both sides separated by the cut K using a tensile testing device, and the peak strength when the test piece was torn 50 mm was measured and recorded as the "tear strength." The tensile testing device used was a "Tensilon Universal Testing Machine RTF" manufactured by Orientec Co., Ltd. The tensile test speed was 500 mm/min. The test results are shown in Table 1.

The tear strength was measured three times for each direction, with the longitudinal direction of the test piece S being the up-down direction (TD) of the tube container 30 of the laminate 10 as the vertical direction, and the transverse direction being the left-right direction (MD, the circumferential direction of the cylindrical body 31) of the tube container 30 of the laminate 10 as the horizontal direction, and the average value was recorded.

As shown in Table 1, except that the tear strength of Example 1 in the longitudinal direction was higher than that of Comparative Example 2, the laminates of Examples 1 to 3 had lower tear strength values in both the longitudinal and transverse directions compared to the laminates of Comparative Examples 1 and 2.

From the evaluation results shown in Table 1, it was found that a laminate having at least the first sealant layer 12, the base material layer (paper base material layer 13), and the second sealant layer 15 laminated in order and having a tear strength of 4N or more and 16N or less can be easily torn by hand compared to other laminates. Furthermore, the body 31 of the tube container 30 of Examples 1 to 4 could be easily torn by hand. In Comparative Example 2, the tear strength in the vertical direction is relatively low, but the tear strength in the horizontal direction is higher than 16N, so depending on the tear direction, it cannot be easily torn by hand. In particular, in the Example, the tear strength in both the vertical and horizontal directions is 4N or more and 16N or less, so it is easy to tear by hand. If the tear strength in both the vertical and horizontal directions is less than 4N, there is a risk of it being torn in an unintended state. Since it is easy to tear by hand, when a tube container is produced using such a laminate, there is no need to break the body of the tube container using a tool such as scissors. This makes it easier to use the contents remaining in the tube container.

In this way, by using a laminate with low tear strength as the body 31 of the tube container 30, the body 31 can be easily torn by hand, and the remaining contents after use can be easily utilized. In particular, the base layer is paper, and the basis weight of the paper used for the base layer is preferably 50 g/ ^m2 or more and 150 g/ ^m2 or less. When the basis weight of the paper is within the above-mentioned predetermined range, the cylindrical body of the tube container can be easily torn by hand. Also, as in Example 3, a preferable tear strength can be obtained when a metal foil is further provided between the base layer and the second sealant layer.

Although the preferred embodiment of the present invention has been described above, the present invention is not limited to the above embodiment and various modifications are possible. For example, in the above embodiment, the laminate has a barrier layer between the paper base layer and the second sealant layer, but a barrier layer is not necessarily required and can be provided as appropriate depending on the characteristics of the contents. Also, in the above embodiment, paper is used as the base layer, but it does not necessarily have to be paper and may be a resin with a certain tear strength.

In the above embodiment, a screw-type cap was used, in which a thread was provided on the outer peripheral surface of the mouth and a thread groove was provided on the inner surface of the cap to screw into the thread, but other types of caps may also be used, such as a type that is connected by a so-called one-touch fitting, in which the cap is attached to and detached from the container by linear movement only in the up and down direction.

10: Laminate (of the body 31 of the tube container 30) 12: First sealant layer 13: Paper base layer 13A: Outer printed portion 14: Barrier layer 15: Second sealant layer 16: Adhesive layer 20: Cap 30: Tube container 31: Body 32: Body attachment portion 33A: Bonded end portion that will be on the outside when the body is attached 33B: Bonded end portion that will be on the inside when the body is attached 34A: Opening (upper side)
34B: Opening (lower side)
35: Shoulder portion 36: Mouth portion 37: Head portion 38: Neck portion 39: Bottom seal portion 40: Zipper

Claims (6)

A laminate for a body part of a tube container, which is formed by sequentially laminating at least a first sealant layer, a paper base layer, and a second sealant layer,
The basis weight of the paper used in the paper base layer is 50 g/m ² or more and 150 g/m ² or less,
The laminate for the body of a tube container is characterized in that the tear strength of the laminate is 4 N or more and 16 N or less in both the vertical direction and the horizontal direction, where the vertical direction is the up-down direction of the tube container and the left-right direction of the tube container is the horizontal direction. 2. The laminate for the body of a tube container according to claim 1 , further comprising an aluminum foil between the paper base layer and the second sealant layer. 3. The laminate for the body of a tube container according to claim 2, further comprising an ethylene-methacrylic acid copolymer (EMAA) layer between the paper base layer and the aluminum foil. The laminate for a body portion of a tube container according to claim 1 , wherein a printing is provided on an outer surface of the first sealant layer. 5. The laminate for the body of a tube container according to claim 1, wherein at least one of the first sealant layer and the second sealant layer contains a plant-derived resin. A tube container, comprising the laminate for the body of a tube container according to any one of claims 1 to 5 as a body part.