Laminate, tube container body, and tube container

Abstract

To provide a laminate that has high recyclability and high scratch resistance, and is capable of producing a tube container body having a white design.SOLUTION: There is provided a laminate comprising at least a first heat-sealing layer, a barrier layer, a second heat-sealing layer, a printing layer, and a surface protection layer in this order. The first heat-sealing layer and the second heat-sealing layer each contain polyethylene as a main component of a resin material. The second heat-sealing layer contains a white pigment and / or the printing layer comprises at least a white printing layer.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] This disclosure relates to a laminate, a tube container body, and a tube container. [Background technology]

[0002] Tube containers are known as packaging containers for filling with paste-like semi-liquid substances such as toothpaste and facial cleansing cream, and for dispensing them for use. A tube container usually comprises a tube container body and a cap. The tube container body generally comprises a body that is closed at one end and open at the other end, and a head having a spout connected to the other open end of the body. A tube container containing the contents is manufactured by filling the body with the contents before closing one end of the body, and then closing the other end of the body.

[0003] Laminates obtained by laminating polyethylene film, polyester film, a gas barrier layer, and aluminum foil are widely used as components for the body of the tube container (see, for example, Patent Documents 1 and 2). [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2006-282184 [Patent Document 2] Japanese Patent Publication No. 2014-231372 [Overview of the Initiative] [Problems that the invention aims to solve]

[0005] In recent years, from the perspective of building a circular economy, there has been a demand for high recyclability in packaging containers. However, as mentioned above, the body of conventional tube containers is made up of a laminate consisting of layers of multiple different materials. Since it is difficult to separate the layers of different materials in the laminate, it is currently difficult to recycle the tube container body. Furthermore, in packaging containers for contents such as toothpaste, it is sometimes desirable to express design features, for example, to represent the whiteness of teeth. However, if a highly recyclable laminate is used as the forming material for the body, the tube container body may be easily scratched, and the design may be reduced.

[0006] This disclosure has been made in view of the above-mentioned problems, and the problem to be solved is to provide a laminate that can be used to manufacture a tube container body having high recyclability, high scratch resistance, and a white-based design.

[0007] The problem addressed by this disclosure is to provide a tube container body and a tube container comprising the above-mentioned laminate. [Means for solving the problem]

[0008] The laminate of the present disclosure comprises, in this order, at least a first heat seal layer, a barrier layer, a second heat seal layer, a printing layer, and a surface protection layer, wherein the first heat seal layer and the second heat seal layer are layers containing polyethylene as the main component of the resin material, the second heat seal layer contains a white pigment, and / or the printing layer comprises at least a white printing layer. The tube container body of the present disclosure comprises a head and a body, the head comprising a shoulder portion connected to one end of the body and an extraction port portion connected to the shoulder portion, and the body comprising the laminate described above. The tube container of this disclosure comprises the tube container body and a cap. [Effects of the Invention]

[0009] According to the present disclosure, a laminate capable of producing a tube container body having high recyclability, high scratch resistance, and a white design property can be provided. According to the present disclosure, a tube container body and a tube container having high recyclability, high scratch resistance, and a white design property and including the above laminate can be provided.

Brief Description of the Drawings

[0010] [Figure 1] FIG. 1 is a schematic cross-sectional view showing an embodiment of the laminate of the present disclosure. [Figure 2] FIG. 2 is a schematic cross-sectional view showing an embodiment of the laminate of the present disclosure. [Figure 3] FIG. 3 is a top view of a web of the tubular body of the tube container body. [Figure 4] FIG. 4 is a perspective view showing an embodiment of a tube container including a tube container body including the laminate of the present disclosure and a cap. [Figure 5] FIG. 5 is a cross-sectional view taken along line A-A of FIG. 4.

Embodiments for Carrying Out the Invention

[0011] Hereinafter, embodiments of the present disclosure will be described in detail. The present disclosure can be implemented in many different forms and is not construed as being limited to the description of the embodiments illustrated below. The drawings may schematically show the width, thickness, shape, etc. of each layer compared to the embodiments for clearer explanation, but this is merely an example and does not limit the interpretation of the present disclosure. In this specification and each figure, elements that are the same as those already described with respect to the previous figures may be denoted by the same reference numerals, and detailed description may be omitted as appropriate.

[0012] Hereinafter, embodiments of the laminate of the present disclosure will be described with reference to the drawings as appropriate. In the following description, the described components (for example, polyethylene, gas barrier resin, additive, white pigment) may be used alone or in combination of two or more.

[0013] ​ The laminate of this disclosure comprises, in the thickness direction of the laminate, at least a first heat seal layer, a barrier layer, a second heat seal layer, a printing layer, and a surface protection layer, in this order.

[0014] Figure 1 shows one embodiment of the laminate of the present disclosure. The laminate 1 in Figure 1 comprises a first heat seal layer 2, a barrier layer 4, a second heat seal layer 6, a printing layer 8, and a surface protection layer 10, in this order in the thickness direction of the laminate.

[0015] The first heat-seal layer is a layer containing polyethylene as the main component of the resin material. The second heat-seal layer is a layer containing polyethylene as the main component of the resin material. Therefore, the laminate of this disclosure has high recyclability. The tube container body comprising this laminate also has high recyclability.

[0016] In this disclosure, "a layer containing polyethylene as the main component of the resin material" means a layer in which the polyethylene content in 100% by mass of the resin material constituting the layer is more than 50% by mass. The above content is preferably 60% by mass or more, more preferably 70% by mass or more, even more preferably 80% by mass or more, and particularly preferably 90% by mass or more or 95% by mass or more.

[0017] The polyethylene content in the entire laminate of this disclosure is preferably 90% by mass or more, more preferably 92% by mass or more, and even more preferably 94% by mass or more. This improves the recyclability of the laminate of this disclosure and the tube container (especially the laminated tube container) body equipped with the laminate.

[0018] In one embodiment, the laminate of the present disclosure does not include polyethylene terephthalate film, aluminum foil, or vapor-deposited film. This improves the recyclability of the laminate of the present disclosure and the tube container (particularly laminated tube container) body containing the laminate.

[0019] The laminate of this disclosure has the printing layer and surface protection layer positioned outside (farther away from) the second heat-seal layer, relative to the position of the first heat-seal layer. In the prior art, the printing layer was placed inside the laminate to protect it, but in this case, separation of the printing layer was difficult, resulting in problems with recyclability. Because the laminate of this disclosure has the above layer configuration, the printing layer and surface protection layer can be easily separated and removed from the laminate. Therefore, the laminate of this disclosure has high recyclability. Furthermore, even in the case of a laminate in which the second heat-seal layer contains a white pigment, the visibility of the printing layer is excellent. The tube container body equipped with this laminate also has similarly high recyclability.

[0020] The laminate of this disclosure includes a surface protection layer on the printed layer. This improves the scratch resistance and slipperiness of the laminate. Therefore, it is possible to suppress damage during the conveying line in the manufacturing process of the laminate and the tube container body, during the conveying line when filling the tube container with contents, and during the transportation of the tube container. In addition, by providing a surface protection layer on the printed layer, a unique tactile feel and high design quality can be given to the laminate.

[0021] Another embodiment of the laminate of this disclosure is shown in Figure 2. The laminate 1 in Figure 2 includes an extruded polyethylene layer 12A between the first heat seal layer 2 and the barrier layer 4, and an extruded polyethylene layer 12B between the barrier layer 4 and the second heat seal layer 6. The second heat seal layer 6 may have a multilayer structure (e.g., three resin layers). The first heat seal layer 2 may also have a multilayer structure (e.g., three resin layers).

[0022] The laminate 1 in Figure 2 comprises a multilayer barrier layer 4. The multilayer barrier layer 4 comprises, in this order, a first polyethylene layer 4A, a first adhesive resin layer 4B, a barrier resin layer 4C containing a gas barrier resin, a second adhesive resin layer 4D, and a second polyethylene layer 4E.

[0023] In this specification, "laminated body" may refer to the raw material itself manufactured on a production line having the layer structure described above, or to each individual laminated body obtained by cutting the raw material, and is not particularly limited as long as it has the layer structure described above. The laminated body pieces are used, for example, to form the body of a tube container.

[0024] Figure 3 shows a top view of the raw material as a laminate of the present disclosure before cutting along the cutting line L. This raw material contains a plurality of continuous laminates (pieces) for forming the body of a tube container. By cutting this raw material along the cutting line L, a plurality of laminate pieces for forming the body of a tube container can be obtained. From the viewpoint of heat sealability, it is preferable that the printed layer and surface protective layer are not formed on both ends of these laminate pieces in the direction perpendicular to the flow direction of the raw material.

[0025] The oxygen permeability of the laminate of this disclosure, measured in accordance with JIS K7126-2:2006 under conditions of 23°C and 40% RH, is preferably 2.0 cc / m². 2 Less than / day / atm, more preferably 1.5cc / m 2 Less than / day / atm, more preferably 1.0 cc / m 2 The oxygen permeability should be less than or equal to / day / atm. A lower oxygen permeability is preferable, but its lower limit is, for example, 0.01 cc / m³. 2 / day / atm would also work.

[0026] The water vapor transmission rate of the laminate of this disclosure, measured in accordance with JIS K7129-2:2019 under conditions of 40°C and 90% RH, is preferably 3.0 g / m². 2 Less than / day, more preferably 2.0 g / m² 2 Less than or equal to / day, more preferably 1.5 g / m² 2 It is less than or equal to / day. A lower water vapor transmission rate is preferable, but its lower limit is, for example, 0.01 g / m³. 2 / day would also work.

[0027] The total light transmittance of the laminate of this disclosure, as measured in accordance with JIS K7375:2008, is preferably 40% or less, more preferably 30% or less, even more preferably 20% or less, and particularly preferably 15% or less. The above total light transmittance of the laminate of this disclosure may be, for example, 5% or more, or 8% or more.

[0028] <First heat seal layer and second heat seal layer> The first heat seal layer contains polyethylene as the main component of the resin material. The second heat seal layer also contains polyethylene as the main component of the resin material. The polyethylene contained in the first heat seal layer and the polyethylene contained in the second heat seal layer may be the same or different. The first heat seal layer and the second heat seal layer can melt and fuse together upon heating.

[0029] When the laminate of this disclosure is used to form the body of a tube container, the first heat seal layer becomes the sealant layer on the inner surface of the body, and the second heat seal layer becomes the sealant layer on the outer surface of the body. That is, the body comprises, from the inside outwards, the first heat seal layer, a barrier layer, the second heat seal layer, a printing layer, and a surface protection layer in this order.

[0030] In the second heat seal layer, it is preferable that the printing layer and the surface protection layer are not formed in the area where heat sealing is planned when forming the body of the tube container. In one embodiment, the first heat seal layer is one surface layer of the laminate, and the surface protection layer is the other surface layer of the laminate, however, the second heat seal layer is exposed in the area where heat sealing is planned.

[0031] Examples of polyethylene include high-density polyethylene, medium-density polyethylene, low-density polyethylene, linear low-density polyethylene, and ultra-low-density polyethylene. Among these, low-density polyethylene and linear low-density polyethylene are preferred from the viewpoint of heat sealability.

[0032] In the present disclosure, the melt flow rate (MFR) of polyethylene may be 0.1 g / 10 min or more, 0.3 g / 10 min or more, 0.5 g / 10 min or more, 50 g / 10 min or less, 30 g / 10 min or less, or 10 g / 10 min or less from the viewpoints of film-forming property and processability. The MFR of polyethylene is measured by Method A in accordance with JIS K7210:1999 under the conditions of a temperature of 190°C and a load of 2.16 kg.

[0033] In the present disclosure, as the high-density polyethylene, polyethylene having a density of 0.945 g / cm 3 or more may be used. As the medium-density polyethylene, polyethylene having a density of 0.928 g / cm 3 more than 0.945 g / cm 3 or less may be used. As the low-density polyethylene, polyethylene having a density of 0.900 g / cm 3 more than 0.928 g / cm 3 or less may be used. As the linear low-density polyethylene, polyethylene having a density of 0.900 g / cm 3 more than 0.928 g / cm 3 or less may be used. As the ultra-low-density polyethylene, polyethylene having a density of 0.900 g / cm 3 or less may be used. The density of polyethylene is measured in accordance with JIS K7112:1999, Method D (density gradient tube method, 23°C).

[0034] Low-density polyethylene is usually polyethylene obtained by polymerizing ethylene by a high-pressure polymerization method (high-pressure method low-density polyethylene). Linear low-density polyethylene is usually polyethylene obtained by polymerizing ethylene and a small amount of α-olefin by a low-pressure polymerization method (for example, a polymerization method using a Ziegler-Natta catalyst or a metallocene catalyst).

[0035] Polyethylenes with different densities or branching can be obtained by appropriately selecting a polymerization method. For example, it is preferable to use a multi-site catalyst such as a Ziegler-Natta catalyst or a single-site catalyst such as a metallocene catalyst as the polymerization catalyst, and to carry out polymerization in one or more stages using one of the following methods: gas-phase polymerization, slurry polymerization, solution polymerization, or high-pressure ionic polymerization.

[0036] In this disclosure, polyethylene includes copolymers of ethylene and other monomers (hereinafter also referred to as "ethylene copolymers"). In this disclosure, the content of ethylene-derived constituent units in polyethylene is preferably 50 mol% or more, more preferably 70 mol% or more, even more preferably 80 mol% or more, and particularly preferably 90 mol% or more or 95 mol% or more. The above content is measured by nuclear magnetic resonance (NMR) spectroscopy.

[0037] Examples of ethylene copolymers include copolymers of ethylene with α-olefins having 3 to 20 carbon atoms. Examples of α-olefins having 3 to 20 carbon atoms include propylene, 1-butene, 1-pentene, 1-hexene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, 1-eicosene, 3-methyl-1-butene, 4-methyl-1-pentene, and 6-methyl-1-heptene. Polyethylene may also be a copolymer of ethylene with vinyl acetate or (meth)acrylic acid esters, etc.

[0038] As polyethylene, biomass-derived polyethylene (hereinafter also referred to as "biomass polyethylene") obtained by polymerizing monomers containing biomass-derived ethylene may be used. Since such biomass polyethylene is a carbon-neutral material, it can reduce the environmental burden in the production of the laminates of this disclosure.

[0039] As polyethylene, recycled polyethylene (hereinafter also referred to as "recycled polyethylene") may be used. Examples of recycled polyethylene include polyethylene recycled by mechanical recycling or chemical recycling. Mechanical recycling generally involves crushing the collected polyethylene film, washing it with alkali to remove dirt and foreign matter from the film surface, drying it at high temperature and reduced pressure for a certain period of time to disperse contaminants remaining inside the film and decontaminate it, removing the dirt from the film and returning it to polyethylene. Chemical recycling generally involves decomposing the collected polyethylene film to the monomer level and then repolymerizing the monomers to obtain polyethylene.

[0040] The above explanation regarding polyethylene can also be applied to polyethylene contained in other layers.

[0041] The polyethylene content in the first heat seal layer is preferably 20% by mass or more, more preferably 25% by mass or more, even more preferably 50% by mass or more, and particularly preferably 80% by mass or more, and may be 99% by mass or less, 97.5% by mass or less, or 95% by mass or less. The polyethylene content in the second heat seal layer is preferably 20% by mass or more, more preferably 25% by mass or more, even more preferably 50% by mass or more, and particularly preferably 80% by mass or more, and may be 99% by mass or less, 97.5% by mass or less, or 95% by mass or less. With such a configuration, for example, the recyclability of a packaging container comprising the laminate of this disclosure can be improved.

[0042] In one embodiment, the second heat-seal layer contains a white pigment. This configuration allows for the imparting of opacity (e.g., a white opacity) to the laminate without using inks such as white ink. For example, if the contents of the packaging container are toothpaste, the packaging container can be given a design that expresses the whiteness of teeth. Furthermore, while the use of inks requires the evaporation and removal of solvents, which can place an environmental burden during the manufacturing of the laminate, the above configuration can further reduce the environmental burden during the manufacturing of the laminate.

[0043] Examples of white pigments include titanium dioxide, barium titanate, strontium titanate, aluminum oxide, magnesium oxide, zinc oxide, barium sulfate, magnesium carbonate, barium carbonate, zirconium oxide, calcium carbonate, white carbon, clay, talc, and barium sulfate.

[0044] The content of the white pigment in the second heat seal layer is preferably 1% by mass or more, more preferably 2.5% by mass or more, even more preferably 5% by mass or more, preferably 80% by mass or less, more preferably 75% by mass or less, even more preferably 50% by mass or less, and particularly preferably 20% by mass or less. This can further improve the effects described above.

[0045] In one embodiment, the second heat-seal layer may be a polyethylene film having a total light transmittance of 5% to 40% as measured in accordance with JIS K7375:2008. This can, for example, impart opacity to the laminate.

[0046] In one embodiment, the first heat-seal layer contains the white pigment described above. The content of the white pigment in the first heat seal layer is preferably 1% by mass or more, more preferably 2.5% by mass or more, even more preferably 5% by mass or more, preferably 80% by mass or less, more preferably 75% by mass or less, even more preferably 50% by mass or less, and particularly preferably 20% by mass or less. This can further improve the effects described above.

[0047] In one embodiment, the first heat-seal layer may be a polyethylene film having a total light transmittance of 5% or more and 40% or less, as measured in accordance with JIS K7375:2008. This can, for example, impart opacity to the laminate.

[0048] In this disclosure, it is preferable that the second heat seal layer contains a white pigment, and the first heat seal layer contains the same or a different white pigment as the white pigment of the second heat seal layer.

[0049] The first heat seal layer may contain additives. The second heat seal layer may contain additives. Examples of additives include crosslinking agents, antioxidants, antiblocking agents, lubricants, UV absorbers, light stabilizers, fillers, reinforcing agents, antistatic agents, pigments, and modifying resins.

[0050] The first heat seal layer may have a multilayer structure. The second heat seal layer may also have a multilayer structure. Examples of multilayer structures include a layer containing medium-density polyethylene, a layer containing medium-density polyethylene, and a layer containing medium-density polyethylene.

[0051] The first heat-seal layer may be a film containing polyethylene. The second heat-seal layer may also be a film containing polyethylene. The film may be a stretched film or an unstretched film. From the viewpoint of heat-sealability, the film is preferably an unstretched film.

[0052] The surface of the first heat seal layer may be surface-treated. The surface of the second heat seal layer may also be surface-treated. This improves the adhesion between these heat seal layers and the layers adjacent to them. Examples of surface treatment methods include physical treatments such as corona discharge treatment, ozone treatment, low-temperature plasma treatment using oxygen gas and / or nitrogen gas, glow discharge treatment, and chemical treatments such as oxidation treatment using chemicals.

[0053] An anchor coat layer may be formed on the surface of the first heat seal layer using a conventionally known anchor coat agent. An anchor coat layer may also be formed on the surface of the second heat seal layer using a conventionally known anchor coat agent.

[0054] The thickness of the first heat seal layer is preferably 30 μm or more, more preferably 50 μm or more, preferably 150 μm or less, and more preferably 130 μm or less. The thickness of the second heat seal layer is preferably 30 μm or more, more preferably 50 μm or more, preferably 150 μm or less, and more preferably 130 μm or less. If the thickness is 30 μm or more, the heat sealability can be further improved. If the thickness is 150 μm or less, the processability of the laminate can be improved.

[0055] The first heat-seal layer and the second heat-seal layer may each be formed by, for example, making a film from a resin composition containing at least polyethylene using a T-die method or an inflation method. The first heat-seal layer and the second heat-seal layer may each be laminated via, for example, an extruded polyethylene layer or an adhesive layer, as described later.

[0056] <Barrier layer> The laminate of this disclosure comprises a barrier layer. Preferably, the barrier layer comprises a barrier resin layer containing a gas barrier resin as the main component of the resin material. This makes it possible to improve the barrier properties of the laminate, such as oxygen barrier properties and water vapor barrier properties, without using dissimilar materials such as vapor-deposited film and aluminum foil. The barrier layer may also serve as the substrate.

[0057] The barrier layer may have a single-layer structure or a multilayer structure. If the barrier layer has a multilayer structure, it is preferable that at least one layer is a barrier resin layer. A multilayer barrier layer may, for example, comprise a polyethylene layer and a barrier resin layer, with an adhesive resin layer between the polyethylene layer and the barrier resin layer. In one embodiment, the multilayer barrier layer comprises a first polyethylene layer, a first adhesive resin layer, a barrier resin layer, a second adhesive resin layer, and a second polyethylene layer. For example, a barrier layer may comprise a linear low-density polyethylene layer, an adhesive resin layer, an ethylene-vinyl alcohol copolymer layer, an adhesive resin layer, and a linear low-density polyethylene layer in this order, or a medium-density polyethylene layer, an adhesive resin layer, an ethylene-vinyl alcohol copolymer layer, an adhesive resin layer, and a medium-density polyethylene layer in this order. In the following description, unless specifically distinguished between the first polyethylene layer and the second polyethylene layer, they will simply be referred to as the polyethylene layer.

[0058] Examples of gas barrier resins include ethylene-vinyl alcohol copolymer (EVOH), polyvinyl alcohol, polyacrylonitrile; polyamides such as nylon 6, nylon 6,6 and polymethaxylylene adipamide (MXD6); polyesters; polyurethanes; and (meth)acrylic resins. Among these, EVOH is preferred from the viewpoint of heat resistance and gas barrier properties.

[0059] EVOH can be obtained, for example, by copolymerizing ethylene with a vinyl ester monomer and then saponifying the resulting product. The copolymerization of ethylene with a vinyl ester monomer can be carried out by any known polymerization method, such as solution polymerization, suspension polymerization, or emulsion polymerization.

[0060] Vinyl acetate is generally used as the vinyl ester monomer, but other vinyl ester monomers may also be used. Examples of other vinyl ester monomers include aliphatic vinyl esters such as vinyl formate, vinyl propionate, vinyl valerate, vinyl butyrate, vinyl isobutyrate, vinyl pivalate, vinyl caprate, vinyl laurate, vinyl stearate, and vinyl versatate; and aromatic vinyl esters such as vinyl benzoate.

[0061] In ethylene-vinyl alcohol copolymer (EVOH), the content of ethylene-derived constituent units (ethylene content) is preferably 20 mol% or more, more preferably 25 mol% or more, preferably 60 mol% or less, and more preferably 50 mol% or less. If the ethylene content is above the lower limit, for example, the processability of the laminate can be improved. If the ethylene content is below the upper limit, for example, the oxygen barrier and / or water vapor barrier properties of the laminate can be improved. The ethylene content is measured by NMR spectroscopy.

[0062] The melting point (Tm) of EVOH is preferably 140°C or higher, more preferably 145°C or higher, even more preferably 150°C or higher, preferably 200°C or lower, more preferably 195°C or lower, and even more preferably 190°C or lower, from the viewpoint of heat resistance. The Tm of EVOH is obtained by differential scanning calorimetry (DSC) in accordance with JIS K7121:2012.

[0063] The average degree of saponification of the vinyl ester component in EVOH may be 90 mol% or higher, 95 mol% or higher, or 99 mol% or higher, from the viewpoint of gas barrier properties. The average degree of saponification is measured in accordance with JIS K6726-1994 (however, EVOH should be a solution homogeneously dissolved in water / methanol solvent).

[0064] The melt flow rate (MFR) of EVOH may be 0.1 g / 10 min or higher, 0.3 g / 10 min or higher, 0.5 g / 10 min or higher, 50 g / 10 min or lower, 30 g / 10 min or lower, or 10 g / 10 min or lower, from the viewpoint of film-forming properties and processability. The MFR of EVOH is measured in accordance with ASTM D1238 under conditions of a temperature of 190°C and a load of 2.16 kg, but the measurement temperature may be 210°C depending on the melting point of EVOH.

[0065] EVOH may be modified by known methods such as urethaneization, acetalization, cyanoethylation, or oxyalkyleneization.

[0066] The gas barrier resin content in the barrier resin layer is preferably more than 50% by mass, more preferably 75% by mass or more, and even more preferably 80% by mass or more, 85% by mass or more, or 90% by mass or more. This improves the barrier properties of the laminate, such as oxygen barrier properties and water vapor barrier properties.

[0067] The barrier resin layer may contain resins other than gas barrier resins. Examples of such resins include polyolefins such as polyethylene and polypropylene; vinyl resins; and cellulose resins. The barrier resin layer may contain the above-mentioned additives.

[0068] The thickness of the barrier resin layer may be 3 μm or more, 5 μm or more, 10 μm or more, 40 μm or less, 30 μm or less, or 20 μm or less. If the thickness is above the lower limit, for example, the effect of the barrier resin layer can be improved. If the thickness is below the upper limit, for example, the recyclability of the laminate can be improved. The ratio of the thickness of the barrier resin layer to the total thickness of the barrier layer may be 5% or more, 10% or more, 15% or more, 40% or less, 35% or less, or 30% or less.

[0069] The polyethylene layers, such as the first polyethylene layer and the second polyethylene layer, contain polyethylene as the main component. Examples of polyethylene include high-density polyethylene, medium-density polyethylene, low-density polyethylene, linear low-density polyethylene, and ultra-low-density polyethylene. The polyethylene contained in the first polyethylene layer and the polyethylene contained in the second polyethylene layer may be the same or different.

[0070] The polyethylene layer may contain biomass polyethylene. The polyethylene layer may contain recycled polyethylene. The polyethylene layer may contain the above-mentioned additives.

[0071] The polyethylene content in the polyethylene layer is preferably 80% by mass or more, more preferably 90% by mass or more, and even more preferably 95% by mass or more. With such a configuration, for example, the recyclability of a packaging container comprising the laminate of this disclosure can be improved.

[0072] The ratio of the thickness of the first polyethylene layer to the total thickness of the barrier layer may be 10% or more, 15% or more, 20% or more, 45% or less, 43% or less, or 40% or less. The ratio of the thickness of the second polyethylene layer to the total thickness of the barrier layer may be 10% or more, 15% or more, 20% or more, 45% or less, 43% or less, or 40% or less.

[0073] The adhesive resin layer contains adhesive resin. Examples of adhesive resins include polyolefins such as polyethylene, modified polyolefins, vinyl resins, polyethers, polyesters, polyamides, polyurethanes, silicone resins, epoxy resins, and phenolic resins. Among these, polyolefins and modified polyolefins are preferred from the viewpoint of recyclability and adhesion, and modified polyolefins such as acid-modified polyolefins are more preferred. Examples of modified polyolefins include modified polyolefins (particularly graft-modified polyolefins) using unsaturated carboxylic acids such as maleic acid and fumaric acid, or their acid anhydrides, esters, or metal salts. Among adhesive resins, modified polyolefins such as modified polyethylene are preferred from the viewpoint of obtaining a composition suitable for monomaterial packaging materials, acid-modified polyolefins such as acid-modified polyethylene are more preferred, and maleic anhydride-modified polyethylene is even more preferred.

[0074] The adhesive resin layer may contain the above-mentioned additives.

[0075] The ratio of the thickness of the first adhesive resin layer to the total thickness of the barrier layer may be 1% or more, 3% or more, 5% or more, 20% or less, 18% or less, or 15% or less. The ratio of the thickness of the second adhesive resin layer to the total thickness of the barrier layer may be 1% or more, 3% or more, 5% or more, 20% or less, 18% or less, or 15% or less.

[0076] The barrier layer comprising the barrier resin layer may be a co-extruded resin film. The co-extruded resin film may be manufactured by forming a film using, for example, the inflation method or the T-die method. The barrier layer comprising the barrier resin layer may be a co-extruded resin film comprising, for example, a linear low-density polyethylene layer, an adhesive resin layer, an ethylene-vinyl alcohol copolymer layer, an adhesive resin layer, and a linear low-density polyethylene layer in this order.

[0077] The barrier layer may contain a compatibilizer. If the barrier layer has a multilayer structure, two or more layers may contain a compatibilizer. By including a compatibilizer in the barrier layer, when the tube container body made using the laminate of this disclosure is heated, melted, and recycled, the miscibility between the gas barrier resin contained in the barrier resin layer and the polyethylene contained in the heat seal layer, etc., can be improved. This effectively suppresses a decrease in its physical properties. It also effectively suppresses a decrease in its transparency.

[0078] While conventionally known compatibilizers can be appropriately selected and used, from the viewpoint of recyclability, unsaturated carboxylic acid-modified polyolefins are preferred, and maleic anhydride-modified polyethylene is more preferred.

[0079] The content of the compatibilizer in the entire barrier layer may be 5% by mass or more, or 20% by mass or less. When the content is 5% by mass or more, the above-mentioned deterioration of physical properties and the deterioration of transparency can be suppressed more effectively. When the content is 20% by mass or less, the moldability of the barrier layer can be improved, and the deterioration of strength of the film made using the resin obtained by recycling the laminate of this disclosure can be suppressed.

[0080] The barrier layer may be a film. This film may be a stretched film or an unstretched film. From the viewpoint of the strength of the laminate, this film may be a stretched film. This stretched film may be a uniaxially oriented film or a biaxially oriented film.

[0081] It is preferable that the surface of the barrier layer is subjected to the above-mentioned surface treatment. This improves the adhesion between the barrier layer and the layer adjacent to the barrier layer.

[0082] When the barrier layer has a single-layer structure, the thickness of the barrier layer is preferably 10 μm or more, more preferably 15 μm or more, preferably 30 μm or less, and more preferably 20 μm or less. If the thickness is 10 μm or more, the gas barrier properties of the laminate can be further improved. If the thickness is 30 μm or less, the recyclability of the laminate can be improved.

[0083] When the barrier layer has a multilayer structure, the total thickness of the barrier layer is preferably 20 μm or more, more preferably 30 μm or more, preferably 100 μm or less, and more preferably 90 μm or less. If the thickness is 20 μm or more, the gas barrier properties of the laminate can be further improved. If the thickness is 100 μm or less, the recyclability of the laminate can be further improved.

[0084] The barrier layer may be formed, for example, by forming a film from a resin composition containing at least a gas barrier resin using a T-die method or an inflation method. Lamination of the barrier layer and the heat seal layer, etc., can be carried out via an extruded polyethylene layer or adhesive layer, etc., as described later.

[0085] <Base material> The laminate of this disclosure may further comprise one or more substrates selected from between the first heat seal layer and the barrier layer, and between the barrier layer and the second heat seal layer. The substrate contains polyethylene as the main component of the resin material.

[0086] Examples of polyethylene include high-density polyethylene, medium-density polyethylene, low-density polyethylene, linear low-density polyethylene, and ultra-low-density polyethylene. Among these, high-density polyethylene and medium-density polyethylene are preferred from the viewpoint of the strength and heat resistance of the substrate, and medium-density polyethylene is more preferred from the viewpoint of the stretchability of the substrate.

[0087] The base material may contain biomass polyethylene. The base material may contain recycled polyethylene. The base material may contain the above-mentioned additives.

[0088] The substrate may have a multilayer structure. Examples of multilayer structures include a layer containing linear low-density polyethylene, a layer containing high-density polyethylene, and a layer containing linear low-density polyethylene.

[0089] The base material may be a film containing polyethylene. The film may be a stretched film or an unstretched film. From the viewpoint of the strength of the laminate, a stretched film is preferred. The stretched film may be a uniaxially oriented film or a biaxially oriented film.

[0090] The surface of the substrate may be treated with the above-mentioned surface treatment. This can improve the adhesion between the substrate and the layer adjacent to the substrate. An anchor coat layer may be formed on the surface of the substrate using a conventionally known anchor coat agent.

[0091] The thickness of the substrate is preferably 10 μm or more, more preferably 20 μm or more, preferably 100 μm or less, and more preferably 70 μm or less. A substrate thickness of 10 μm or more can further improve its strength and heat resistance. A substrate thickness of 100 μm or less can improve the processability of the laminate.

[0092] The base material may be prepared, for example, by forming a film from a resin composition containing at least polyethylene using a T-die method or an inflation method.

[0093] <Extruded polyethylene layer> In one embodiment, the laminate of the present disclosure may include one or more extruded polyethylene layers selected from any interlayers, for example, between a second heat-seal layer and a barrier layer, and between a barrier layer and a first heat-seal layer. This improves the interlayer adhesion strength in the laminate and thus suppresses delamination in, for example, the laminate and tube container.

[0094] Examples of polyethylene included in the extruded polyethylene layer include high-density polyethylene, medium-density polyethylene, low-density polyethylene, linear low-density polyethylene, and ultra-low-density polyethylene. Among these, low-density polyethylene, linear low-density polyethylene, and ultra-low-density polyethylene are preferred from the viewpoint of interlayer adhesion, and low-density polyethylene is more preferred.

[0095] The melt flow rate (MFR) of polyethylene contained in the extruded polyethylene layer is preferably 1 g / 10 min or more, more preferably 2 g / 10 min or more, even more preferably 3 g / 10 min or more, preferably 50 g / 10 min or less, more preferably 30 g / 10 min or less, and even more preferably 20 g / 10 min or less, from the viewpoint of film-forming properties and processability. The MFR of polyethylene is measured by Method A in accordance with JIS K7210:1999, under conditions of a temperature of 190°C and a load of 2.16 kg.

[0096] The melting point (Tm) of the polyethylene contained in the extruded polyethylene layer is preferably 100°C or higher, preferably 140°C or lower, more preferably 130°C or lower, and even more preferably 120°C or lower, from the viewpoint of balancing heat resistance and adhesiveness. The Tm of the polyethylene is obtained by differential scanning calorimetry (DSC) in accordance with JIS K7121:2012.

[0097] The extruded polyethylene layer may contain biomass polyethylene. The extruded polyethylene layer may contain recycled polyethylene. The extruded polyethylene layer may contain the above-mentioned additives.

[0098] The polyethylene content in the extruded polyethylene layer is preferably 80% by mass or more, more preferably 90% by mass or more, and even more preferably 95% by mass or more. This configuration can improve, for example, adhesion and recyclability.

[0099] The thickness of the extruded polyethylene layer is preferably 5 μm or more, more preferably 10 μm or more, preferably 30 μm or less, and more preferably 25 μm or less. A thickness of 5 μm or more improves interlayer adhesion. A thickness of 30 μm or less reduces the production cost of the laminate and improves its productivity.

[0100] The extruded polyethylene layer may be formed, for example, by melt-extruding a resin composition containing at least polyethylene onto a barrier layer or the like. The melting temperature at this time may be, for example, 280°C or higher, 290°C or higher, 340°C or lower, or 335°C or lower.

[0101] <Adhesive layer> In one embodiment, the laminate of the present disclosure may include adhesive layers between any layers, for example, between the second heat seal layer and the barrier layer, and between the barrier layer and the first heat seal layer.

[0102] The adhesive layer may be formed, for example, with a conventionally known adhesive. The adhesive may be a one-component curing adhesive, a two-component curing adhesive, or a non-curing adhesive.

[0103] The adhesive may be a solvent-free adhesive or a solvent-based adhesive, but from the viewpoint of environmental impact, a solvent-free adhesive is preferred. Examples of solvent-free adhesives include polyether-based adhesives, polyester-based adhesives, silicone-based adhesives, epoxy-based adhesives, and urethane-based adhesives. Among these, a two-component curing type urethane-based adhesive is preferred. Examples of solvent-based adhesives include rubber-based adhesives, vinyl-based adhesives, silicone-based adhesives, epoxy-based adhesives, phenol-based adhesives, olefin-based adhesives, and urethane-based adhesives. Among these, a two-component curing type urethane-based adhesive is preferred.

[0104] The adhesive layer may contain pigments such as titanium dioxide, zinc oxide, and carbon black; dyes such as disperse dyes, acid dyes, and cationic dyes; and additives such as antioxidants, lubricants, colorants, stabilizers, wetting agents, thickeners, coagulants, gelling agents, anti-settlement agents, softeners, curing agents, plasticizers, leveling agents, UV absorbers, and flame retardants. The thickness of the adhesive layer is, for example, between 1 μm and 5 μm.

[0105] <Print layer> The laminate of this disclosure comprises a printed layer, the printed layer including an image. Examples of images include text, shapes, symbols, patterns, and combinations thereof. Images may also include textual information such as product name, name of contents in the packaging, manufacturer, and ingredients. Images may be solid color (so-called solid images).

[0106] The printed layer may be formed using a printing layer composition such as a thermoplastic resin composition, a thermosetting resin composition, and an energy-ray curable resin composition, each containing a colorant. Specifically, the printed layer contains a resin component such as a thermoplastic resin, a cured thermosetting resin, or a cured energy-ray curable resin, and a colorant.

[0107] The thermoplastic resin composition contains a thermoplastic resin and a coloring agent. Examples of thermoplastic resins include polyolefins, chlorinated polyolefins, polystyrene, (meth)acrylic resins, vinyl resins, acetal resins, polyesters, polyurethanes, polycarbonates, polyamides, polyimides, cellulose resins, petroleum resins, and fluororesins. The thermoplastic resin composition may contain the above-mentioned additives.

[0108] A thermosetting resin composition is a composition that contains a thermosetting resin, a colorant, and optionally a curing agent, and hardens upon heating. The thermosetting resin composition may also be a so-called thermosetting ink.

[0109] Examples of thermosetting resins include phenolic resins, melamine resins, urea resins, epoxy resins, unsaturated polyesters, thermosetting polyurethanes, and silicone resins; as well as (meth)acrylic thermosetting resins such as polyester (meth)acrylate, urethane (meth)acrylate, epoxy (meth)acrylate, polyether (meth)acrylate, polyol (meth)acrylate, melamine (meth)acrylate, and triazine-based (meth)acrylate. Examples of curing agents include epoxy-based curing agents and isocyanate-based curing agents. The thermosetting resin composition may contain the above-mentioned additives.

[0110] An energy-ray curable resin composition is a composition that contains a compound having an energy-ray curable functional group (hereinafter also referred to as "energy-ray curable compound") and a colorant, and is cured by energy-ray irradiation. The energy-ray curable resin composition may also be a so-called ultraviolet-curable ink, and is preferably a (meth)acrylic ultraviolet-curable ink.

[0111] Examples of energy rays include electromagnetic waves such as ultraviolet rays, infrared rays, X-rays, and gamma rays; and charged particle beams such as electron beams, proton beams, and neutron beams. Among these, ultraviolet rays are preferred from the viewpoint of curing speed, availability of irradiation sources, and cost. Examples of ultraviolet irradiation sources include mercury lamps, high-pressure mercury lamps, ultra-high-pressure mercury lamps, xenon lamps, metal halide lamps, and LEDs. The irradiation dose of ultraviolet rays is, for example, 5 mJ / cm². 2 More than 5,000mJ / cm 2 The following applies:

[0112] Examples of energy-ray curable functional groups include ethylenically unsaturated groups such as (meth)acryloyl groups, vinyl groups, and allyl groups; as well as epoxy groups and oxetanyl groups.

[0113] Examples of energy ray curable compounds include compounds having ethylenically unsaturated groups, with compounds having two or more ethylenically unsaturated groups being preferred, and polyfunctional (meth)acrylate compounds being preferred. Both monomers and oligomers can be used as polyfunctional (meth)acrylate compounds.

[0114] Examples of polyfunctional (meth)acrylate monomers include difunctional (meth)acrylate monomers such as ethylene glycol di(meth)acrylate, bisphenol A tetraethoxy di(meth)acrylate, bisphenol A tetrapropoxy di(meth)acrylate, and 1,6-hexanediol di(meth)acrylate; and trifunctional or more (meth)acrylate monomers such as trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol hexa(meth)acrylate, dipentaerythritol tetra(meth)acrylate, and isocyanuric acid-modified tri(meth)acrylate. The number of energy-ray-curable functional groups of the polyfunctional (meth)acrylate monomer is preferably 2 to 6, more preferably 2 to 3.

[0115] The polyfunctional (meth)acrylate monomer may have a modified molecular skeleton; for example, monomers modified with ethylene oxide, propylene oxide, caprolactone, and isocyanuric acid may be used.

[0116] Examples of polyfunctional (meth)acrylate oligomers include polyester (meth)acrylate, urethane (meth)acrylate, epoxy (meth)acrylate, and polyether (meth)acrylate.

[0117] When the energy ray-curable compound is an ultraviolet-curable compound, it is preferable that the energy ray-curable composition (ultraviolet-curable resin composition) contains at least one selected from a photopolymerization initiator and a photopolymerization accelerator.

[0118] Examples of photopolymerization initiators include acetophenones, benzophenones, thioxanthones, α-hydroxyalkylphenones, Michler ketones, benzoin, benzyldimethylketal, benzoylbenzoate, and α-acyloxime esters.

[0119] Photopolymerization accelerators are components that can reduce polymerization inhibition by air during curing and accelerate the curing speed. Examples include isoamyl p-dimethylaminobenzoate and ethyl p-dimethylaminobenzoate. The energy-ray curable resin composition may contain the above-mentioned additives.

[0120] Examples of colorants include pigments such as inorganic and organic pigments; and dyes such as acid dyes, direct dyes, disperse dyes, oil-soluble dyes, metal-containing oil-soluble dyes, and sublimation dyes. Specific examples of pigments include titanium dioxide, zinc oxide, carbon black, iron oxide, iron yellow, ultramarine, metallic pigments, pearl pigments, and fluorescent pigments. The printed layer may be a high-luminosity layer with a high metallic sheen.

[0121] The resin component content in the printed layer may be 10% by mass or more, 30% by mass or more, 50% by mass or more, 99% by mass or less, 97% by mass or less, or 95% by mass or less. The colorant content in the printed layer may be 1% by mass or more, 3% by mass or more, 5% by mass or more, 90% by mass or less, 70% by mass or less, or 50% by mass or less.

[0122] In one embodiment, the printed layer comprises at least a white printed layer. The white printed layer is, for example, a so-called solid white image. This configuration allows for, for example, the imparting of opacity (e.g., a sense of white opacity) to the laminate. For example, if the contents of the packaging container are toothpaste, the packaging container can be given a design that expresses the whiteness of teeth. The thickness of the white printed layer is preferably 0.01 μm or more, more preferably 0.5 μm or more, even more preferably 1 μm or more, preferably 20 μm or less, more preferably 10 μm or less, and even more preferably 5 μm or less.

[0123] The printed layer may comprise, for example, a white printed layer and other printed layers provided on the white printed layer. The layer configuration here is in the order of a second heat seal layer, a white printed layer, other printed layers, and a surface protection layer. The white printed layer can be formed, for example, using a printing layer composition containing the white pigment described above.

[0124] The printing layer composition may contain an organic solvent and / or water from the viewpoint of improving coatability and other properties. Examples of organic solvents include hydrocarbons such as toluene and xylene; ketones such as acetone and methyl ethyl ketone; esters such as ethyl acetate, cellosolve acetate and butyl cellosolve acetate; and alcohols such as propanol.

[0125] For example, the printing layer composition may be applied to a second heat-seal layer and dried, and then the printing layer may be formed by heating to the temperature required for curing in the case of a thermosetting resin composition, or by irradiating with energy rays in the case of an energy-ray curable resin composition. If the printing layer composition does not contain organic solvents or water, drying is not necessary.

[0126] Printing methods for the printed layer include, for example, letterpress printing, flexographic printing, gravure printing, offset printing, screen printing, inkjet printing, and thermal transfer printing. When the printed layer is formed by letterpress printing or flexographic printing, it is preferable to use an energy-ray curable resin composition, and more preferable to use an ultraviolet-curable resin composition.

[0127] The printed layer may contain a sublimation dye. The printed layer in this embodiment can be formed, for example, by sublimation transfer printing using a thermal transfer sheet.

[0128] The thickness of the printed layer is preferably 0.01 μm or more, more preferably 0.5 μm or more, even more preferably 1 μm or more, preferably 30 μm or less, more preferably 10 μm or less, and even more preferably 5 μm or less. If the printed layer comprises a white printed layer and other printed layers, the sum of the thickness of the white printed layer and the thickness of the other printed layers should be within the above range of printed layer thickness.

[0129] <Surface protective layer> The laminate of this disclosure comprises, for example, a surface protection layer on the printed layer to improve the scratch resistance and weather resistance of the printed layer. Preferably, the laminate of this disclosure comprises a surface protection layer that covers the entire area of ​​the printed layer. From the viewpoint of the visibility of the printed layer, the surface protection layer is preferably transparent in the visible light region, and more preferably colorless and transparent.

[0130] The surface protection layer may be formed using a surface protection layer composition such as a thermoplastic resin composition, a thermosetting resin composition, or an energy ray curable resin composition. Specifically, the printed layer contains a thermoplastic resin, a cured thermosetting resin, or a cured energy ray curable resin. Among these, from the viewpoint of improving scratch resistance and weather resistance, the surface protection layer preferably contains a cured thermosetting resin or a cured energy ray curable resin, and more preferably contains a cured energy ray curable resin. The proportion of the above cured products in the total resin components of the surface protection layer is preferably 80% by mass or more, more preferably 90% by mass or more.

[0131] The thermoplastic resin composition contains a thermoplastic resin. Specific examples of thermoplastic resins are as described above. The thermoplastic resin composition may also contain the above-mentioned additives.

[0132] A thermosetting resin composition is a composition that contains a thermosetting resin and, optionally, a curing agent, and hardens upon heating. The thermosetting resin composition may also be a so-called thermosetting varnish. Specific examples of thermosetting resins and curing agents are as described above. The thermosetting resin composition may also contain the above-mentioned additives.

[0133] An energy-ray curable resin composition is a composition that contains an energy-ray curable compound and at least one selected optionally from a photopolymerization initiator and a photopolymerization accelerator, and that cures upon irradiation with energy rays. The energy-ray curable resin composition may also be a so-called ultraviolet-curable varnish, preferably a (meth)acrylic ultraviolet-curable varnish. Specific examples of the energy-ray curable compound, photopolymerization initiator, and photopolymerization accelerator are as described above. The energy-ray curable resin composition may also contain the above-mentioned additives.

[0134] The surface protective layer composition may contain an organic solvent and / or water to improve its applicability and other properties. Specific examples of organic solvents are as described above.

[0135] For example, a surface protective layer composition may be applied to a printed layer and dried, and then, in the case of a thermosetting resin composition, heated to the temperature required for curing, or in the case of an energy-ray curable resin composition, irradiated with energy rays to form a surface protective layer. If the surface protective layer composition does not contain organic solvents or water, drying is not necessary.

[0136] Examples of printing methods for the surface protective layer include letterpress printing, flexographic printing, gravure printing, offset printing, screen printing, inkjet printing, and thermal transfer printing. When the surface protective layer is formed by letterpress printing or flexographic printing, it is preferable to use an energy-ray curable resin composition, and more preferable to use an ultraviolet-curable resin composition.

[0137] The thickness of the surface protective layer is preferably 0.5 μm or more, more preferably 1 μm or more, preferably 15 μm or less, and more preferably 10 μm or less. This can improve, for example, the scratch resistance and weather resistance of the laminate.

[0138] In one embodiment, the present disclosure describes a method for manufacturing a laminate comprising a first heat-seal layer, a barrier layer, and a second heat-seal layer. The laminate is then cut at predetermined intervals in the flow direction. This yields multiple long laminates. Next, a printing layer and a surface protection layer are formed on each of the cut laminates. This method is possible because the printing layer and surface protection layer are formed on the outermost layer of the laminate. This method can accommodate various flow dimensions and width dimensions, and laminates with printing layers can be produced in small batches. Furthermore, in one embodiment, the use of high-density polyethylene results in high slipperiness of the inner and outer film surfaces, allowing for high-speed tubing production and thus improving the productivity of the tubes.

[0139] [Tube container body] The tube container body of this disclosure comprises the laminate described above. The tube container body of this disclosure will now be described with reference to the drawings. Figure 4 is a simplified diagram showing the configuration of the tube container 20, and Figure 5 is a cross-sectional view AA of Figure 4. As shown in Figure 4, the tube container body 21 comprises a head portion 22 and a body portion 23, and the body portion 23 is made of the laminate of this disclosure.

[0140] <Head> The head portion 22 includes a shoulder portion 24 connected to one end of the body portion 23 and an outlet portion 25 connected to the shoulder portion 24. In one embodiment, the spout portion 25 is provided with threads 27 for screwing on a cap 26.

[0141] In one embodiment, the head is formed from a resin composition containing polyethylene. This improves the recyclability of the tube container body. Examples of polyethylene include high-density polyethylene, medium-density polyethylene, low-density polyethylene, linear low-density polyethylene, and ultra-low-density polyethylene. Among these, high-density polyethylene is preferred from the viewpoint of shape retention and moldability.

[0142] The above resin composition may contain at least one selected from biomass polyethylene and recycled polyethylene. The above resin composition may contain the above additives.

[0143] The head can be manufactured by conventionally known methods. For example, the head can be manufactured by compression molding or injection molding and then joined to the body.

[0144] When manufacturing a tube container body using a compression molding method, the body may be attached to a male mold having a protrusion at the top, the male and female molds may be placed opposite each other, molten resin composition may be supplied into the male and female molds and compressed to form the head, and the head may be joined to one of the openings of the body, thereby manufacturing a tube container body comprising a head and a body.

[0145] When manufacturing a tube container body using injection molding, the body may be attached to a male mold having a protrusion at the top, the male and female molds may be placed opposite each other, molten resin composition may be supplied from the gate and injection molded to form the head, and the head may be joined to one of the openings of the body, thereby manufacturing a tube container body comprising a head and a body.

[0146] <torso> In the tube container body 21 of the present disclosure, the body portion 23 is connected to the shoulder portion 24 of the head portion 22. The body portion 23 includes a welded portion 28 formed by overlapping the first heat-seal layer side surface of one end of the laminate of the present disclosure with the second heat-seal layer side surface of the other end so that they are in contact, rolling it into a cylindrical shape, and then heat-sealing the overlapped portion. The body portion 23 also includes a bottom seal portion 29 formed by heat-sealing the opening of the rolled-in-cylindrical laminate.

[0147] Examples of conventional heat sealing methods include bar seals, rotary roll seals, belt seals, impulse seals, high-frequency seals, ultrasonic seals, and flame seals.

[0148] For example, a cylindrical body may be manufactured by overlapping the laminate of the present disclosure so that the surface of the first heat seal layer at one end and the surface of the second heat seal layer at the other end are in contact, rolling them into a cylindrical shape, and then heat sealing the overlapped portion. From the viewpoint of heat sealability, it is preferable that one end of the overlapping assembly is the first heat seal layer and the other end is the second heat seal layer. In this case, the first heat seal layer and the second heat seal layer melt and join together, forming a welded portion.

[0149] Therefore, in the second heat-seal layer, it is preferable that the printed layer and the surface protective layer are not formed in the area where heat sealing is planned when forming the body of the tube container. This allows for good heat sealing in the above area when forming a cylindrical body using the laminate of this disclosure.

[0150] In the above embodiment, the welded portion is formed by overlapping, but the first heat-seal layers may be joined by butting the same surfaces at both ends of the laminate together and heat-sealing them. In this case, a printed layer and a surface protection layer may be formed on the second heat-seal layer at both ends of the laminate. In this case, a joining tape may be attached to the outer surface of the body so as to cover the joint. It is preferable not to provide a printed layer and a surface protection layer at the location where the joining tape is attached to the laminate. The joining tape may be provided on both the inner and outer surfaces of the body.

[0151] [Tube container] The tube container of this disclosure will be described below with reference to the drawings. As shown in Figure 4, the tube container 20 of this disclosure comprises a tube container body 21 and a cap 26 attached to the head 22.

[0152] <Tube container body> As the tube container itself has been described above, it will not be described here.

[0153] <Cap> The cap is detachably attached to the dispensing port at the top and serves to close the dispensing port. In one embodiment, the cap is formed from a resin composition containing a thermoplastic resin. Examples of thermoplastic resins include polyethylene and polyolefins such as polypropylene, polyester, cellulose resin, and vinyl resin. From the viewpoint of recyclability, polyethylene is particularly preferred. Examples of polyethylene include high-density polyethylene, medium-density polyethylene, low-density polyethylene, linear low-density polyethylene, and ultra-low-density polyethylene. Among these, high-density polyethylene is preferred from the viewpoint of shape retention and ease of opening.

[0154] The above resin composition may contain at least one selected from biomass polyethylene and recycled polyethylene. The above resin composition may contain the above additives.

[0155] As shown in Figure 4, the cap may be a screw type with a groove on the inner surface of the cap that screws onto the threads 27 of the dispensing port 25, or it may be a cap that is fitted by pressing it onto the dispensing port 25.

[0156] This disclosure relates, for example, to the following [1] to

[19] . [1] A laminate comprising, in this order, at least a first heat seal layer, a barrier layer, a second heat seal layer, a printing layer, and a surface protection layer, wherein the first heat seal layer and the second heat seal layer are layers containing polyethylene as the main component of a resin material, the second heat seal layer contains a white pigment, and / or the printing layer comprises at least a white printing layer. [2] The laminate according to [1], wherein the second heat seal layer contains a white pigment, and the first heat seal layer contains the same or a different white pigment as the white pigment. [3] The laminate according to [2], wherein the content ratio of the white pigment in the second heat seal layer and the first heat seal layer is 1% by mass or more and 80% by mass or less, respectively. [4] The laminate according to any one of the above [1] to [3], wherein the second heat seal layer and the first heat seal layer are polyethylene films having a total light transmittance of 5% or more and 40% or less (measured in accordance with JIS K7375:2008). [5] The laminate according to any one of the above [1] to [4], wherein the barrier layer comprises a barrier resin layer containing a gas barrier resin as the main component of the resin material. [6] The laminate according to [5], wherein the barrier layer comprises a first polyethylene layer, a first adhesive resin layer, the barrier resin layer, a second adhesive resin layer, and a second polyethylene layer. [7] The laminate according to any one of the above [1] to [6], wherein the thickness of the barrier layer is 20 μm or more and 100 μm or less. [8] The laminate according to any one of [1] to [7], wherein the surface protective layer contains a cured product of an energy ray curable resin or a cured product of a thermosetting resin. [9] The laminate according to any one of the above [1] to [8], comprising one or more extruded polyethylene layers or adhesive layers selected from between the second heat seal layer and the barrier layer, and between the barrier layer and the first heat seal layer.

[10] The laminate according to any one of the above [1] to [9], wherein the polyethylene contained in the first heat seal layer and the second heat seal layer is at least one selected from low-density polyethylene and linear low-density polyethylene, respectively.

[11] The laminate according to any one of the above [1] to

[10] , wherein the thickness of the first heat seal layer and the second heat seal layer are each 30 μm or more and 150 μm or less.

[12] The oxygen permeability measured in accordance with JIS K7126-2:2006 at a temperature of 23°C and a humidity of 40%RH is 2.0 cc / m³. 2 The humidity level is less than or equal to / day / atm, and the water vapor transmission rate measured in accordance with JIS K7129-2:2019 at a temperature of 40°C and a humidity of 90%RH is 3.0 g / m³. 2 A laminate according to any one of the above [1] to

[11] , wherein the value is less than or equal to / day.

[13] The laminate according to any one of the above [1] to

[12] , wherein the polyethylene content in the entire laminate is 90% by mass or more.

[14] A laminate for forming the body of a tube container, wherein the first heat seal layer is a sealant layer on the inner surface of the body, and the second heat seal layer is a sealant layer on the outer surface of the body, according to any one of the claims [1] to

[13] .

[15] The laminate according to

[14] , wherein the second heat seal layer is not formed in the area where heat sealing is planned to form the body of the tube container body, and the printed layer and the surface protective layer are not formed therein.

[16] A tube container body comprising a head and a body, wherein the head comprises a shoulder portion connected to one end of the body and an extraction port portion connected to the shoulder portion, and the body is composed of a laminate as described in any one of the items [1] to

[15] above.

[17] The tube container body according to

[16] , wherein the head is formed of a resin composition containing polyethylene.

[18] A tube container comprising the tube container body described in

[16] above and a cap.

[19] The tube container according to

[18] , wherein the cap is formed of a resin composition containing polyethylene. [Examples]

[0157] The laminates of this disclosure will be described in more detail below with reference to examples, but the laminates of this disclosure are not limited to the following examples. In the following description, linear low-density polyethylene will be referred to as "LLDPE", low-density polyethylene as "LDPE", and ethylene-vinyl alcohol copolymer as "EVOH".

[0158] [Example 1] LLDPE (Dow Chemical, DOWLEX 2045G, density 0.920 g / cm³) 3 ) and adhesive resin (Mitsui Chemicals, Admer NF557) and EVOH (Kuraray, EVAL H171B, density 1.17 g / cm³) 3 , ethylene content 38 mol%, adhesive resin (Mitsui Chemicals, Admer NF557), and LLDPE (Dow Chemical, DOWLEX2045G, density 0.920 g / cm³) 3 A gas barrier film was obtained by co-extruding five layers of the materials using the inflation method. The gas barrier film has a five-layer structure with a total thickness of 75 μm, comprising, in this order, an LLDPE layer with a thickness of 21.9 μm, an adhesive resin layer with a thickness of 6.25 μm, an EVOH layer with a thickness of 18.75 μm, an adhesive resin layer with a thickness of 6.25 μm, and an LLDPE layer with a thickness of 21.9 μm.

[0159] On one side of the gas barrier film, LDPE (Sumitomo Chemical Co., Ltd., Sumikasen L705, density: 0.919 g / cm³) is applied. 3 A 20 μm thick extruded polyethylene layer was formed by melting and extruding (melting point: 106°C, MFR: 7 g / 10 min) at 330°C, and a 120 μm thick milky white polyethylene film was laminated through this extruded polyethylene layer as a first heat seal layer. The milky white polyethylene film is a film obtained by forming a film of a mixture of 90% by mass polyethylene and 10% by mass white pigment (titanium dioxide-based pigment), and has a total light transmittance of approximately 10%. The polyethylene in the milky white polyethylene film is a mixture of ENABLE 2705MC, EXCEED 1327MA, and LDPE LD2420F manufactured by PTT CHEMICAL.

[0160] On the other side of the gas barrier film, the above-mentioned LDPE (Sumikasen L705) was melt-extruded at 330°C to form an extruded polyethylene layer with a thickness of 15 μm. A 120 μm thick milky white polyethylene film was then laminated as a second heat-seal layer through this extruded polyethylene layer. The milky white polyethylene film was obtained by forming a film of a mixture of 90% by mass polyethylene and 10% by mass white pigment (titanium dioxide-based pigment), and its total light transmittance is approximately 10%. The polyethylene in the milky white polyethylene film is a mixture of EXXON CHEMICAL's ENABLE 2705MC, EXXON CHEMICAL's EXCEED 1327MA, and PTT CHEMICAL's LDPE LD2420F.

[0161] On the second heat-seal layer, an ultraviolet-curable ink (T&K TOKA, UV161) was applied by letterpress printing, dried, and then cured by ultraviolet light to form a 2 μm thick printed layer. On this printed layer surface, an ultraviolet-curable printing varnish (T&K TOKA, Bestcure UV LTP FL OP varnish) was applied, dried, and then cured by ultraviolet light to form a 3 μm thick surface protective layer. However, the printed layer and surface protective layer were not formed in the areas corresponding to a 4.0 mm region at one end and a 2.0 mm region at the other end in the width direction (perpendicular to the flow direction of the raw material) of the laminate individual pieces obtained by the processing described later.

[0162] In this way, a laminate was obtained. The laminate comprises, in order, a surface protection layer (3 μm) (outermost layer), a printed layer (2 μm), a milky white polyethylene film (120 μm, second heat-seal layer), an extruded polyethylene layer (15 μm), a gas barrier film (75 μm), an extruded polyethylene layer (20 μm), and a milky white polyethylene film (120 μm, first heat-seal layer) (innermost layer).

[0163] [Example 2] A laminate was obtained in the same manner as in Example 1, except that a UV-curable ink (T&K TOKA, UV Flexo CF) was applied to the second heat-seal layer by flexographic printing, dried, and then cured by UV irradiation to form a 2 μm thick printed layer, and a UV-curable printing varnish (Toyo Ink, FD FL OP varnish AQF4) was applied to the surface of this printed layer, dried, and then cured by UV irradiation to form a 3 μm thick surface protective layer.

[0164] [Example 3] In the same manner as in Example 1, an extruded polyethylene layer and a milky polyethylene film were laminated on one side of a gas barrier film. On the other side of the gas barrier film, the above-mentioned LDPE (Sumikasen L705) was melt-extruded at 330°C to form an extruded polyethylene layer with a thickness of 15 μm, and a polyethylene film with a thickness of 120 μm was laminated through this extruded polyethylene layer as a second heat-seal layer. The polyethylene film was obtained by forming a film from a mixture of EXXON CHEMICAL ENABLE 2705MC, EXXON CHEMICAL EXCEED 1327MA, and PTT CHEMICAL LDPE LD2420F.

[0165] On the second heat-seal layer, white ink was printed in solid color over the entire surface except for the areas corresponding to the edges described below. Subsequently, UV-curable ink (T&K TOKA, UV161) was applied by letterpress printing, dried, and then cured by UV light to form a 2 μm thick printed layer. On this printed layer surface, UV-curable printing varnish (T&K TOKA, Best Cure UV LTP FL OP varnish) was applied, dried, and then cured by UV light to form a 3 μm thick surface protective layer. However, the printed layer and surface protective layer were not formed in the areas corresponding to a 4.0 mm region on one edge and a 2.0 mm region on the other edge in the width direction (direction perpendicular to the flow direction of the raw material) of the laminate individual pieces obtained by the processing described later.

[0166] In this way, a laminate was obtained. The laminate comprises, in order, a surface protection layer (3 μm) (outermost layer), a printed layer (2 μm), a polyethylene film (120 μm, second heat-seal layer), an extruded polyethylene layer (15 μm), a gas barrier film (75 μm), an extruded polyethylene layer (20 μm), and a milky white polyethylene film (120 μm, first heat-seal layer) (innermost layer).

[0167] [Comparative Example 1] As a barrier substrate, a vapor-deposited film (Dai Nippon Printing Co., Ltd., IB-PET-WUB) was used, which consisted of a vapor-deposited film formed on a 12 μm thick biaxially oriented polyethylene terephthalate film. A urethane-based gravure ink (Toyo Ink Co., Ltd., NEW-LP Super) was applied to the vapor-deposited film of the barrier substrate by gravure printing and dried to form a 1 μm thick printed layer. In this way, a printing substrate was obtained.

[0168] Each layer was laminated onto the printed substrate using a tandem dry laminating machine. Specifically, a two-component urethane-based curing adhesive (manufactured by Rock Paint, solvent-based adhesive, main component: RU-80, curing agent: H-5) was applied to the printing layer formation surface of the printing substrate and dried to form a 3 μm thick adhesive layer. A 130 μm thick milky white polyethylene film was then laminated on top of this adhesive layer. The milky white polyethylene film was made of polyethylene (density: 0.920 g / cm³). 3 The film was obtained by forming a film of a mixture of 93.5% by mass of (MFR: 1.9g / 10 min) and 6.5% by mass of white pigment, and the total light transmittance is approximately 20%.

[0169] Next, a two-component urethane-based curing adhesive (manufactured by Rock Paint, solvent-based adhesive, main component: RU-004, curing agent: H-1) was applied to the side of the printing substrate opposite to the side where the printing layer was formed, and dried to form a 3 μm thick adhesive layer. A 130 μm thick polyethylene film containing an antistatic agent was then laminated on top of this adhesive layer. The polyethylene film containing the antistatic agent was made of polyethylene (density: 0.920 g / cm³). 3 This film is obtained by forming a film of a mixture of 98% by mass of an antistatic agent and 2% by mass of an antistatic agent.

[0170] A laminate was obtained in the manner described above. The laminate comprises, in order, an antistatic agent-containing polyethylene film (130 μm) (outermost layer), an adhesive layer (3 μm), a vapor-deposited film (12 μm), a printed layer (1 μm), an adhesive layer (3 μm), and a milky white polyethylene film (130 μm) (innermost layer).

[0171] [Comparative Example 2] A 12 μm thick biaxially oriented polyethylene terephthalate (PET) film (Toyobo, E5200) was used as the substrate. A urethane-based gravure ink (Toyo Ink, NEW-LP Super) was applied to the substrate by gravure printing and dried to form a 1 μm thick printed layer. In this way, a printing substrate was obtained.

[0172] (1) A 100 μm thick milky white polyethylene film was prepared. The milky white polyethylene film is made of polyethylene (density: 0.920 g / cm³). 3 The film was obtained by forming a film of a mixture of 94% by mass of (melting point: 118℃, MFR: 1.9g / 10min) and 6% by mass of white pigment, and the total light transmittance was approximately 20%. A vapor-deposited film (Dai Nippon Printing, IB-PET-WUB), in which a vapor-deposited film was formed on a 12μm thick biaxially oriented polyethylene terephthalate film, was laminated onto a milky white polyethylene film. (2) On the vapor-deposited film, an ethylene-methacrylic acid copolymer (Mitsui DuPont Polychemical, Nucrel N0908C) was melt-extruded at 330℃ to form an extruded layer with a thickness of 25μm, and an 80μm thick polyethylene film (Aicello Co., Ltd., L100N) was laminated through this extruded layer. (3) The above LDPE (Sumikasen L705) was melt-extruded at 330°C onto the printing layer forming surface of the printing substrate to form an extruded polyethylene layer with a thickness of 25 μm, and the laminates obtained in (1) and (2) above were laminated via this extruded polyethylene layer.

[0173] On the side of the printing substrate opposite to the surface where the printing layer is formed, the above-mentioned LDPE (Sumikasen L705) was melt-extruded at 330°C to form an extruded polyethylene layer with a thickness of 25 μm. A 100 μm thick polyethylene film containing an antistatic agent was then laminated through this extruded polyethylene layer. The polyethylene film containing the antistatic agent is made of polyethylene (density: 0.916 g / cm³). 3 The film is obtained by forming a film of a mixture containing 98.5% by mass of ) a static agent, 1% by mass of an antistatic agent, and 0.5% by mass of an antiblocking agent.

[0174] A laminate was obtained in the manner described above. The laminate comprises, in order, an antistatic agent-containing polyethylene film (100 μm) (outermost layer), an extruded polyethylene layer (25 μm), a substrate (12 μm), a printed layer (1 μm), an extruded polyethylene layer (25 μm), a milky white polyethylene film (100 μm), a vapor-deposited film (12 μm), an extruded layer (25 μm), and a polyethylene film (80 μm) (innermost layer).

[0175] [Preparation of tube containers] The laminates obtained in the examples and comparative examples were processed into individual laminate pieces with a width of 157.3 mm using a bobbin cutter. The ends in the width direction were overlapped so that the overlap width was approximately 1.2 mm, and then the overlapped ends were heat-sealed under the conditions of 0.1 MPa, 120°C, and 1.0 second to obtain a cylindrical raw material. The obtained raw material was cut to a length of 184.2 mm in the length direction to produce a cylindrical body that would become the body of the tube container. The cylindrical body was mounted on a mandrel for forming the tube container, and a head consisting of a frustoconical shoulder and a cylindrical extraction port continuous therewith was attached to one end of the cylindrical body using high-density polyethylene (Suntec J345, manufactured by Asahi Kasei, density 0.956 g / cm³). 3 A tube container body was fabricated using a compression molding method with the material shown in Figure 4. The spout at the top of the obtained tube container body has an outer diameter of 30.4 mm and a height of 9.5 mm, and a spiral groove is provided on the side of the spout. The outer diameter of the shoulder is 50 mm. Next, the high-density polyethylene was injected into a mold for cap molding and molded to produce a cap. In this way, a tube container was obtained.

[0176] [Gas barrier properties test] For the laminates obtained in the examples and comparative examples, the oxygen permeability (cc / m³) was measured using an oxygen permeability analyzer (OXTRAN, MOCON) under conditions of 23°C and 40% RH, in accordance with JIS K7126-2:2006. 2 The / day / atm value was measured.

[0177] For the laminates obtained in the examples and comparative examples, the water vapor transmission rate (g / m³) was measured using a water vapor transmission rate analyzer (PERMATRAN, MOCON) under conditions of 40°C and 90% RH, in accordance with JIS K7129-2:2019. 2 The measurement was taken ( / day).

[0178] Measurements were performed on two layers of each laminate, and the average value of the obtained values ​​was calculated.

[0179] [Total light transmittance] The total light transmittance of the laminates obtained in the examples and comparative examples was measured using a haze meter (HM-150, manufactured by Murakami Color Technology Laboratory Co., Ltd.) in accordance with JIS K7375:2008. Measurements were performed on three laminates, and the average value of the obtained values ​​was calculated.

[0180] [Side seam tensile strength] A test specimen was obtained by cutting a 15 mm wide strip from the body of the tube container, perpendicular to the side seam (tube joint) (TD direction of the laminate). In accordance with JIS K6854-2:1999, this test specimen was pulled at a test speed of 300 mm / min using a tensile testing machine (Orientec Co., Ltd., STA-1150), and the tensile strength (side seam strength) at which the test specimen broke was measured. Measurements were performed on three test specimens, and the average value of the obtained values ​​was calculated.

[0181] [Shoulder adhesion strength] Test specimens were obtained by cutting a 15mm wide strip in the hem direction (MD direction of the laminate) from two locations where the body and shoulder of the tube container are bonded: the side seam (tube bonding area) and the location 180° opposite to it. These test specimens were pulled at a test speed of 300mm / min using a tensile testing machine (Orientec Co., Ltd., STA-1150), and the peel strength (adhesion strength) at which the body separated from the shoulder was measured. Measurements were performed on three test specimens, and the average value of the obtained values ​​was calculated.

[0182] [Table 1]

[0183] In the examples, it was found that the raw material properties were equivalent to or better than those of the comparative examples.

[0184] [Initial ink adhesion] Cellotape® was applied to the laminates obtained in the examples and comparative examples, and a cross-cut test was performed using a cross-cut tester to confirm the adhesion between the ink (printed layer) and the film. ○: Excellent ink adhesion. △: Good ink adhesion. ×: Poor ink adhesion.

[0185] [Ink adhesion after immersion] The laminates obtained in the examples and comparative examples were immersed in water or a solution (treatment) for 24 hours, then removed. Cellophane tape (registered trademark) was applied to the laminate, and a cross-cut test was performed using a cross-cut tester to confirm the adhesion between the ink (printing layer) and the film. ○: Excellent ink adhesion. △: Good ink adhesion. ×: Poor ink adhesion.

[0186] [JSPS Examination] The outermost layer of the laminates obtained in the examples and comparative examples was set in the JSPS testing machine "FR-2" (manufactured by Suga Test Machinery Co., Ltd.), and a JSPS test was performed on a metal plate (stainless steel) and a film in accordance with JIS L-0849:2013, with a test load of 200 gf, a reciprocating speed of 30 cpm, a stroke of 120 mm, and 300 reciprocating cycles. For the metal test, the metal was rubbed against the laminate with the surface protective layer (polyethylene film containing an antistatic agent in Comparative Examples 1 and 2) facing upwards. For the film test, the laminate was wrapped around the metal with the surface protective layer (polyethylene film containing an antistatic agent in Comparative Examples 1 and 2) facing upwards, and the surface protective layers (polyethylene films containing antistatic agents) were rubbed against each other. After the test, the condition of the outermost layer of the laminate was visually confirmed, and the scratch resistance of the outermost layer of the laminate was evaluated according to the following evaluation criteria.

[0187] ○: Excellent △: Good ×: inferior

[0188] [Slipperiness test] For the outermost layer surface of the laminates obtained in the examples and comparative examples, the static friction coefficient and dynamic friction coefficient against metal plates and films (same meaning as in the JSPS test) were measured using a slip tester "TR-2" (manufactured by Toyo Seiki) in accordance with JIS K7125:1999, at a test speed of 100 mm / min.

[0189] [Table 2]

[0190] [Small lot orders accepted] The processability of tube containers obtained using a laminate with a width of 120.0 mm was evaluated in small lots (10,000 to 30,000 units / lot) according to the following criteria.

[0191] ○: Good (low loss rate or good machinability) △: Slightly inferior (high loss rate or poor machinability) ×: Significantly inferior (very high loss rate, or very poor machinability)

[0192] [Monomaterial] The polyethylene content (monomaterial ratio) was calculated from the specific gravity of the materials constituting each layer of the laminates obtained in the examples and comparative examples, and the thickness of each layer was evaluated based on the evaluation criteria below. In addition, the monomaterial status of the laminates obtained in the examples and comparative examples was determined in accordance with the CEFLEX guidelines. A "○" was given if the laminate conformed to the CEFLEX guidelines, and a "×" was given if it did not.

[0193] ◎: The polyethylene content in the laminate is 90% by mass or more, and since the printed layer and surface protective layer are located on the surface of the laminate, the printed layer and surface protective layer are easy to separate. ○: Although the polyethylene content in the laminate is 90% by mass or more, the printed layer and surface protective layer are not located on the surface of the laminate, making it difficult to separate them. △: The polyethylene content in the laminate is less than 90% by mass.

[0194] [Table 3]

[0195] The tube container bodies obtained in the examples exhibited good side seam tensile strength and shoulder adhesive strength. Compared to the laminates of Comparative Examples 1 and 2, the laminates of Examples 1 to 3 had better slipperiness, better scratch resistance, were suitable for small-lot production, and had excellent recyclability. Since the printed layer of the laminates of Comparative Examples 1 and 2 is located inside the laminate, it is considered difficult to produce them in small lots. [Explanation of symbols]

[0196] 1: Laminate 2: First heat seal layer 4: Barrier layer 4A: First polyethylene layer 4B: First adhesive resin layer 4C: Barrier resin layer 4D: Second adhesive resin layer 4E: Second polyethylene layer 6: Second heat seal layer 8: Printing layer 10: Surface protective layer 12: Extruded polyethylene layer 20: Tube container 21: Tube container body 22:Head 23: Torso 24:Shoulder 25:Extraction port 26: Cap 27: Spiral 28: Welded part 29: Bottom seal section

Claims

1. A laminate comprising, at least, a first heat seal layer, a barrier layer, a second heat seal layer, a printing layer, and a surface protection layer in this order, The first heat seal layer and the second heat seal layer are layers containing polyethylene as the main component of the resin material, The second heat-seal layer contains a white pigment, and / or the printing layer comprises at least a white printing layer. The barrier layer comprises a first polyethylene layer, a first adhesive resin layer, a barrier resin layer containing a gas barrier resin as the main component of the resin material, a second adhesive resin layer, and a second polyethylene layer. The polyethylene content in the entire laminate is 90% by mass or more. Laminated structure.

2. A laminate comprising, in this order, at least a first heat seal layer, a barrier layer, a second heat seal layer, a printing layer, and a surface protection layer, The first heat seal layer and the second heat seal layer are layers containing polyethylene as the main component of the resin material, The second heat-seal layer contains a white pigment, and / or the printing layer comprises at least a white printing layer. A laminate in which the second heat-seal layer contains a white pigment, and the first heat-seal layer contains the same or a different white pigment as the white pigment.

3. A laminate comprising, in this order, at least a first heat seal layer, a barrier layer, a second heat seal layer, a printing layer, and a surface protection layer, The first heat seal layer and the second heat seal layer are layers containing polyethylene as the main component of the resin material, The second heat-seal layer contains a white pigment, and / or the printing layer comprises at least a white printing layer. The second heat-seal layer contains a white pigment, and the first heat-seal layer contains the same or a different white pigment as the white pigment. A laminate in which the content ratio of the white pigment in the second heat seal layer and the first heat seal layer is 1% by mass or more and 80% by mass or less, respectively.

4. A laminate comprising, in this order, at least a first heat seal layer, a barrier layer, a second heat seal layer, a printing layer, and a surface protection layer, The first heat seal layer and the second heat seal layer are layers containing polyethylene as the main component of the resin material, The second heat-seal layer contains a white pigment, and / or the printing layer comprises at least a white printing layer. A laminate in which the second heat-seal layer and the first heat-seal layer are each polyethylene films having a total light transmittance of 5% to 40% (measured in accordance with JIS K7375:2008).

5. The laminate according to claim 1, wherein the barrier layer comprises a barrier resin layer containing a gas barrier resin as the main component of the resin material.

6. A laminate comprising, in this order, at least a first heat seal layer, a barrier layer, a second heat seal layer, a printing layer, and a surface protection layer, The first heat seal layer and the second heat seal layer are layers containing polyethylene as the main component of the resin material, The second heat-seal layer contains a white pigment, and / or the printing layer comprises at least a white printing layer. The barrier layer comprises a first polyethylene layer, a first adhesive resin layer, a barrier resin layer containing a gas barrier resin as the main component of the resin material, a second adhesive resin layer, and a second polyethylene layer, forming a laminate.

7. The laminate according to claim 6, wherein the thickness of the barrier layer is 20 μm or more and 100 μm or less.

8. A laminate comprising, in this order, at least a first heat seal layer, a barrier layer, a second heat seal layer, a printing layer, and a surface protection layer, The first heat seal layer and the second heat seal layer are layers containing polyethylene as the main component of the resin material, The second heat-seal layer contains a white pigment, and / or the printing layer comprises at least a white printing layer. A laminate in which the surface protective layer contains a cured product of an energy-ray curable resin or a cured product of a thermosetting resin.

9. The laminate according to claim 1, further comprising one or more extruded polyethylene layers or adhesive layers selected from between the second heat seal layer and the barrier layer, and between the barrier layer and the first heat seal layer.

10. The laminate according to claim 1, wherein the polyethylene contained in the first heat seal layer and the second heat seal layer is at least one selected from low-density polyethylene and linear low-density polyethylene, respectively.

11. The laminate according to claim 1, wherein the thickness of the first heat seal layer and the second heat seal layer is 30 μm or more and 150 μm or less, respectively.

12. The oxygen permeability measured in accordance with JIS K7126-2:2006, under conditions of 23°C and 40% RH, is 2.0 cc / m³. ２ It is less than or equal to / day / atm, The water vapor transmission rate measured in accordance with JIS K7129-2:2019, under conditions of 40°C and 90% RH, is 3.0 g / m³. ２ / day or less, The laminate according to claim 1.

13. A laminate comprising, in this order, at least a first heat seal layer, a barrier layer, a second heat seal layer, a printing layer, and a surface protection layer, The first heat seal layer and the second heat seal layer are layers containing polyethylene as the main component of the resin material, The second heat-seal layer contains a white pigment, and / or the printing layer comprises at least a white printing layer. A laminate in which the polyethylene content in the entire laminate is 90% by mass or more.

14. A laminate for forming the body of a tube container, wherein the first heat seal layer is a sealant layer on the inner surface side of the body, and the second heat seal layer is a sealant layer on the outer surface side of the body, according to claim 1.

15. A laminate for forming the body of a tube container, The laminate comprises, in this order, at least a first heat seal layer, a barrier layer, a second heat seal layer, a printing layer, and a surface protection layer. The first heat seal layer and the second heat seal layer are layers containing polyethylene as the main component of the resin material, The second heat-seal layer contains a white pigment, and / or the printing layer comprises at least a white printing layer. The first heat seal layer is a sealant layer on the inner surface of the body, and the second heat seal layer is a sealant layer on the outer surface of the body. A laminate in which, in the second heat-seal layer, the printing layer and the surface protection layer are not formed in the area where heat sealing is planned to form the body of the tube container.

16. A tube container body comprising a head and a body, The head comprises a shoulder portion connected to one end of the body and an extraction port portion connected to the shoulder portion, and the body is made of a laminate according to any one of claims 1 to 15. Tube container body.

17. The tube container body according to claim 16, wherein the head portion is formed of a resin composition containing polyethylene.

18. The tube container body according to claim 16, cap and A tube container equipped with the following features.

19. The tube container according to claim 18, wherein the cap is formed of a resin composition containing polyethylene.

Images