Laminate, tube container body, and tube container

Abstract

To provide a laminate with high recyclability and high interlaminar adhesive strength.SOLUTION: A laminate at least comprises a first resin layer, a first extruded resin layer, a stretched substrate, a second extruded resin layer, and a second resin layer. The laminate further has a design layer on the first extruded resin layer side and / or on the second extruded resin layer side of the stretched substrate. The first resin layer, the first extruded resin layer, the stretched substrate, the second extruded resin layer and the second resin layer each contain polyethylene as a major component.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] Conventional tube containers are manufactured using packaging materials that include, for example, a polyethylene film as a heat-seal layer, a polyethylene terephthalate film with a printed layer formed on it as a printing substrate, and a polyethylene terephthalate film or aluminum foil with a vapor-deposited film formed on it as a barrier substrate (see Patent Document 1). However, it is generally difficult to separate the films from a packaging container that includes, for example, polyethylene film and aluminum foil. Therefore, such packaging containers are not suitable for recycling after use and are not actively recycled. As a result, packaging materials are being considered that include a stretched polyethylene film (stretched polyethylene film) as a base material and a polyethylene film as a heat-seal layer (see Patent Document 2). [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2010-214768 [Patent Document 2] Japanese Patent Publication No. 2005-053223 [Overview of the project] [Problems that the invention aims to solve]

[0005] In order to improve the functionality of a tube container, it is desirable that the interlayer adhesive strength between the base material and the heat-seal layer be high in a laminate (packaging material) which has a stretched polyethylene film as the base material and a polyethylene film as the heat-seal layer.

[0006] The problem addressed by this disclosure is to provide a laminate having high recyclability and high interlayer adhesive strength. [Means for solving the problem]

[0007] The laminate of the present disclosure comprises at least a first resin layer, a first extruded resin layer, a stretched substrate, a second extruded resin layer, and a second resin layer, further comprising a design layer on the surface of the stretched substrate facing the first extruded resin layer and / or on the surface facing the second extruded resin layer, wherein the first resin layer, the first extruded resin layer, the stretched substrate, the second extruded resin layer, and the second resin layer each contain polyethylene as a main component. [Effects of the Invention]

[0008] According to this disclosure, it is possible to provide a laminate having high recyclability and high interlayer adhesive strength. By using the laminate of this disclosure, for example, packaging containers such as tube container bodies having high recyclability and high interlayer adhesive strength can be manufactured. [Brief explanation of the drawing]

[0009] [Figure 1] Figure 1 is a schematic cross-sectional view showing one embodiment of the laminate of the present disclosure. [Figure 2] Figure 2 is a schematic cross-sectional view showing one embodiment of the laminate of the present disclosure. [Figure 3] Figure 3 is a schematic cross-sectional view showing one embodiment of the laminate of the present disclosure. [Figure 4] Figure 4 is a schematic cross-sectional view showing an embodiment of the laminate of the present disclosure. [Figure 5] Figure 5 is a schematic cross-sectional view showing an embodiment of the laminate of the present disclosure. [Figure 6] Figure 6 is a schematic cross-sectional view showing an embodiment of the laminate of the present disclosure. [Figure 7] Figure 7 is a perspective view showing an embodiment of a tube container including a tube container body provided with the laminate of the present disclosure and a cap. [Figure 8] Figure 8 is a cross-sectional view taken along the line A-A of Figure 7.

Embodiments for Carrying Out the Invention

[0010] 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 exemplified below. The drawings may schematically represent the width, thickness, shape, etc. of each layer as compared with the embodiments for the sake of 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 previously shown figures may be denoted by the same reference numerals, and detailed description may be omitted as appropriate.

[0011] Hereinafter, embodiments of the laminate of the present disclosure will be described while appropriately using the drawings. 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.

[0012] In the present disclosure, the "main component" refers to a component having a content ratio in the layer of more than 50% by mass.

[0013] [Laminate] The laminate of the present disclosure comprises, for example, a first resin layer, a first extruded resin layer, a stretched substrate, a second extruded resin layer, and a second resin layer, in this order in the thickness direction of the laminate. The laminate further comprises a design layer on the surface of the stretched substrate facing the first extruded resin layer and / or on the surface facing the second extruded resin layer. The first resin layer, the first extruded resin layer, the stretched substrate, the second extruded resin layer, and the second resin layer each contain polyethylene as a main component.

[0014] One embodiment of the laminate of this disclosure is shown in Figures 1 to 6. The laminate 1 in Figure 1 comprises a first resin layer 2, a first extruded resin layer 8A, a design layer 4a, a stretched base material 4, a second extruded resin layer 8B, and a second resin layer 6 in this order. The laminate 1 in Figure 2 comprises a first resin layer 2, a first extruded resin layer 8A, a stretched base material 4, a design layer 4a, a second extruded resin layer 8B, and a second resin layer 6 in this order. As shown in Figures 3 and 4, an anchor coat layer 4b may be provided between the extruded resin layer and the design layer.

[0015] The laminate 1 in Figure 5 comprises, in this order, a first resin layer 2, a first extruded resin layer 8A, an anchor coat layer 4b, a design layer 4a, a stretched base material 4, an anchor coat layer 4b, a second extruded resin layer 8B, another base material 7, a third extruded resin layer 8C, and a second resin layer 6. The laminate 1 in Figure 6 comprises, in this order, a first resin layer 2, a first extruded resin layer 8A, an anchor coat layer 4b, a stretched base material 4, a design layer 4a, an anchor coat layer 4b, a second extruded resin layer 8B, another base material 7, a third extruded resin layer 8C, and a second resin layer 6. An anchor coat layer (not shown) may be provided between the extruded resin layer and the design layer.

[0016] The first resin layer may have a multilayer structure (e.g., three resin layers). The second resin layer may have a multilayer structure (e.g., three resin layers). The stretched substrate may have a multilayer structure (e.g., three resin layers). Other substrates may have a multilayer structure (e.g., three resin layers).

[0017] The laminate of this disclosure comprises a first resin layer, a first extruded resin layer, a stretched substrate, a second extruded resin layer, and a second resin layer, each containing polyethylene as its main component. Therefore, the laminate of this disclosure has high recyclability. The tube container body comprising this laminate also has similarly high recyclability.

[0018] The polyethylene content in the entire laminate of this disclosure is preferably 90% by mass or more, more preferably 92% by mass or more. This improves the recyclability of the laminate of this disclosure and the tube container (particularly the laminated tube container) body equipped with the laminate.

[0019] In one embodiment, the laminate of the present disclosure does not include polyethylene terephthalate film, aluminum foil, or vapor-deposited film. Printability, lamination suitability, and sealability can be reproduced using only polyethylene without the use of dissimilar materials. This improves the recyclability of the laminate of the present disclosure and the tube container (particularly laminated tube container) body equipped with the laminate.

[0020] 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.

[0021] <First resin layer and second resin layer> The first resin layer contains polyethylene as its main component. The second resin layer also contains polyethylene as its main component. The polyethylene contained in the first resin layer and the polyethylene contained in the second resin layer may be the same or different.

[0022] The first resin layer has heat-sealing properties. The second resin layer also has heat-sealing properties. Therefore, the first resin layer and the second resin layer can melt and fuse together upon heating.

[0023] When the laminate of this disclosure is used to form the body of a tube container, the first resin layer is a sealant layer (heat seal layer) on the outer surface side of the body, and the second resin layer is a sealant layer (heat seal layer) on the inner surface side of the body. That is, the body comprises, for example, a second heat-sealable resin layer, a second extruded resin layer, a stretched substrate, a first extruded resin layer, and a first heat-sealable resin layer, in this order from the inside to the outside of the body. In one embodiment, the first resin layer is one surface layer of the laminate, and the second resin layer is the other surface layer of the laminate.

[0024] Examples of polyethylene include high-density polyethylene, medium-density polyethylene, low-density polyethylene, linear low-density polyethylene, and ultra-low-density polyethylene. Among these, medium-density polyethylene, low-density polyethylene, and linear low-density polyethylene are preferred from the viewpoint of heat sealability.

[0025] In this disclosure, the melt flow rate (MFR) of polyethylene may be 0.1 g / 10 min to 50 g / 10 min, 0.3 g / 10 min to 30 g / 10 min, or 0.5 g / 10 min to 10 g / 10 min, from the viewpoint of film-forming properties and processability. The MFR of polyethylene is measured by Method A in accordance with JIS K7210, under conditions of a temperature of 190°C and a load of 2.16 kg.

[0026] In this disclosure, high-density polyethylene has a density of 0.945 g / cm³. 3 Ultra-high density polyethylene can be used, and as medium-density polyethylene, its density is 0.926 g / cm³. 3 Super 0.945g / cm 3 The following polyethylenes can be used, and as low-density polyethylene, those with a density of 0.900 g / cm³ can be used. 3 Super 0.926g / cm 3 The following polyethylenes can be used, and as linear low-density polyethylene, the density is 0.900 g / cm³. 3 Super 0.926g / cm3 The following polyethylenes can be used, and as ultra-low density polyethylene, the density is 0.900 g / cm³. 3 The following polyethylenes can be used. The density of the polyethylene is measured in accordance with JIS K7112 (for example, Method D (density gradient pipe method, 23°C)).

[0027] Low-density polyethylene is typically polyethylene obtained by polymerizing ethylene using a high-pressure polymerization method (high-pressure low-density polyethylene). Linear low-density polyethylene is typically polyethylene obtained by polymerizing ethylene and a small amount of α-olefin using a low-pressure polymerization method (e.g., polymerization using a Ziegler-Natta catalyst or a metallocene catalyst).

[0028] 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.

[0029] 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 can be measured, for example, by nuclear magnetic resonance (NMR).

[0030] Examples of ethylene copolymers include copolymers of ethylene and 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 and vinyl acetate or (meth)acrylic acid esters, etc.

[0031] 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.

[0032] As polyethylene, recycled polyethylene obtained through mechanical or chemical recycling may be used. This reduces the environmental burden of laminates or packaging materials. Mechanical recycling generally involves crushing 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 dirt from the film and returning it to polyethylene. Chemical recycling generally involves decomposing collected polyethylene film down to the monomer level and then repolymerizing the monomers to obtain polyethylene.

[0033] The polyethylene content in the first resin layer is preferably 80% by mass or more, more preferably 90% by mass or more, and even more preferably 95% by mass or more. The polyethylene content in the second resin 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.

[0034] The first resin layer may contain additives. The second resin 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.

[0035] The second resin layer may contain a pigment such as a white pigment. With this configuration, opacity (e.g., a white opacity) can be imparted to the laminate without using inks such as white ink. When inks are used, solvents must be evaporated and removed, which tends to place an environmental burden on the laminate during manufacturing, but with the above configuration, the environmental burden during laminate manufacturing can be reduced.

[0036] 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.

[0037] The second resin layer may be, for example, a polyethylene film having a total light transmittance of 10% to 40% as measured in accordance with JIS K7375. This can, for example, impart opacity to the laminate.

[0038] The first resin layer may have a multilayer structure. The second resin 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.

[0039] The first resin layer may be a film containing polyethylene as the main component. The second resin layer may be a film containing polyethylene as the main component. The film may be a stretched film or an unstretched film. From the viewpoint of heat sealability, an unstretched film is preferred. The second resin layer may be a film containing polyethylene and a white pigment.

[0040] The surface of the first resin layer may be surface-treated. The surface of the second resin layer may also be surface-treated. This improves the adhesion between these resin 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.

[0041] An anchor coat layer may be formed on the surface of the first resin layer using a conventionally known anchor coat agent. An anchor coat layer may also be formed on the surface of the second resin layer using a conventionally known anchor coat agent.

[0042] The thickness of the first resin layer is preferably 30 μm to 250 μm, more preferably 50 μm to 200 μm. The thickness of the second resin layer is preferably 30 μm to 250 μm, more preferably 50 μm to 200 μm. If the thickness is 30 μm or more, the heat sealability can be further improved. If the thickness is 250 μm or less, the processability of the laminate can be improved.

[0043] The first resin layer and the second resin layer can be produced, for example, by forming a film from a polyethylene-containing resin composition using a T-die method or an inflation method. The first resin layer and the second resin layer can each be laminated, for example, via an extruded resin layer described later.

[0044] The second resin layer may comprise a polyethylene layer and a gas barrier resin layer. The second resin layer may comprise, for example, a first polyethylene layer, a first adhesive resin layer, a gas barrier resin layer, a second adhesive resin layer, and a second polyethylene layer, in this order. By including a gas barrier resin layer in the second resin layer, barrier properties such as oxygen barrier and water vapor barrier properties in the laminate can be improved without using dissimilar materials such as vapor-deposited film or aluminum foil. In the following description, unless otherwise specifically distinguished, the first polyethylene layer and the second polyethylene layer will simply be referred to as the polyethylene layer.

[0045] When the second resin layer comprises a gas barrier resin layer, the polyethylene content is preferably more than 50% by mass and 95% by mass or less, more preferably 55% by mass and 90% by mass or less, and even more preferably 60% by mass and 85% by mass or less, based on the second resin layer. When the second resin layer comprises a gas barrier resin layer, the gas barrier resin content is preferably 1% by mass and 30% by mass or less, more preferably 3% by mass and 20% by mass or less, and even more preferably 5% by mass and 15% by mass or less, based on the second resin layer. With such a configuration, for example, the balance between the recyclability and gas barrier properties of the laminate can be improved.

[0046] The gas barrier resin layer contains a gas barrier resin. Examples of gas barrier resins include ethylene-vinyl alcohol copolymers (EVOH), polyvinyl alcohol, polyacrylonitrile; polyamides such as nylon 6, nylon 6,6 and polymethaxylylene adipamide; polyesters; polyurethanes; and (meth)acrylic resins. Among these, EVOH is preferred from the viewpoint of heat resistance and gas barrier properties.

[0047] 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.

[0048] 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.

[0049] In ethylene-vinyl alcohol copolymers (EVOH), the content of ethylene-derived constituent units (ethylene content) is preferably 20 mol% to 60 mol%, more preferably 25 mol% to 50 mol%. 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.

[0050] The melting point (Tm) of EVOH is preferably 140°C to 200°C, more preferably 145°C to 195°C, and even more preferably 150°C to 190°C, from the viewpoint of heat resistance. The Tm of EVOH is obtained by differential scanning calorimetry (DSC) in accordance with JIS K7121.

[0051] 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 (however, EVOH should be a solution homogeneously dissolved in water / methanol solvent).

[0052] The melt flow rate (MFR) of EVOH may be between 0.1 g / 10 min and 50 g / 10 min, between 0.3 g / 10 min and 30 g / 10 min, or between 0.5 g / 10 min and 10 g / 10 min, from the viewpoint of film-forming 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.

[0053] EVOH may be modified by known methods such as urethaneization, acetalization, cyanoethylation, or oxyalkyleneization.

[0054] The gas barrier resin content in the gas barrier resin layer is preferably 50% by mass or more, 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.

[0055] The thickness of the gas barrier resin layer may be 3 μm or more and 30 μm or less, or 5 μm or more and 20 μm or less. If the thickness is above the lower limit, for example, the effect of the gas 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 gas barrier resin layer to the total thickness of the second resin layer may be 3% or more and 20% or less, or 5% or more and 15% or less.

[0056] The polyethylene layer contains polyethylene as its main component. Details of polyethylene are as described above. Examples of polyethylene included in the polyethylene layer include high-density polyethylene, medium-density polyethylene, low-density polyethylene, linear low-density polyethylene, and ultra-low-density polyethylene. From the viewpoint of heat sealability, medium-density polyethylene, low-density polyethylene, and linear low-density polyethylene are preferred. Biomass polyethylene, or mechanically or chemically recycled polyethylene may be used as the polyethylene.

[0057] 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.

[0058] The polyethylene layer may contain the above-mentioned additives.

[0059] The ratio of the thickness of the first polyethylene layer to the total thickness of the second resin layer may be 10% to 45%, 15% to 43%, or 20% to 40%.

[0060] The second resin layer may include an adhesive resin layer between the polyethylene layer and the gas barrier resin layer. This can improve, for example, the adhesion between the polyethylene layer and the gas barrier resin layer.

[0061] 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.

[0062] The adhesive resin layer may contain the above-mentioned additives.

[0063] The ratio of the thickness of the first adhesive resin layer to the total thickness of the second resin layer may be 1% or more and 20% or less, 3% or more and 18% or less, or 5% or more and 15% or less.

[0064] In one embodiment, the second resin layer comprising the gas barrier resin layer is a co-extruded resin film. The co-extruded resin film can be manufactured, for example, by forming a film using an inflation method or a T-die method. The second resin layer comprising the gas 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.

[0065] <Stretched base material> The stretched substrate is mainly composed of polyethylene, that is, it contains polyethylene in an amount exceeding 50% by mass. Because the resin material constituting the stretched substrate is polyethylene, which is the same type of resin material as the resin material constituting the first and second resin layers, a laminate having such a configuration can be suitably used as a packaging material for manufacturing monomaterial packaging containers.

[0066] For example, polyethylene includes high-density polyethylene, medium-density polyethylene, low-density polyethylene, linear low-density polyethylene, and ultra-low-density polyethylene, all of which are classified as the same type of resin material. On the other hand, polyethylene and polyester, for example, are not classified as the same type of resin material.

[0067] From the viewpoint of strength and heat resistance, the stretched substrate preferably contains at least one selected from medium-density polyethylene and high-density polyethylene. As polyethylene, biomass polyethylene or mechanically or chemically recycled polyethylene may be used.

[0068] The polyethylene MFR constituting the stretched substrate is preferably 0.1 g / 10 min to 50 g / 10 min, more preferably 0.2 g / 10 min to 30 g / 10 min, even more preferably 0.2 g / 10 min to 10 g / 10 min, and particularly preferably 0.2 g / 10 min to 5.0 g / 10 min, from the viewpoint of film-forming properties and processability.

[0069] For example, when a stretched substrate is manufactured by the T-die method, the MFR of the polyethylene constituting the stretched substrate is preferably 3.0 g / 10 min to 20 g / 10 min from the viewpoint of film-forming properties and processability. For example, when a stretched substrate is manufactured by the inflation method, the MFR of the polyethylene constituting the stretched substrate is preferably 0.2 g / 10 min to 5.0 g / 10 min from the viewpoint of film-forming properties and processability.

[0070] From the viewpoint of heat resistance, the melting point of the polyethylene constituting the stretched base material is preferably 100°C to 140°C, more preferably 110°C to 140°C, and even more preferably 120°C to 140°C.

[0071] The polyethylene content in the stretched substrate 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 the recyclability of the laminate, for example. If the stretched substrate has a multilayer structure, the polyethylene content in each layer constituting the stretched substrate is preferably 80% by mass or more, more preferably 90% by mass or more, and even more preferably 95% by mass or more, independently of each other. This configuration can improve the recyclability of the laminate, for example.

[0072] The stretched substrate may contain the above-mentioned additives.

[0073] In one embodiment, the haze of the stretched substrate may be 25% or less, 15% or less, or 10% or less. The lower limit of the haze may be 0.1% or 1%. The haze of the stretched substrate is measured in accordance with JIS K7136.

[0074] The stretched substrate may contain a pigment such as a white pigment. With this configuration, opacity (e.g., a white opacity) can be imparted to the laminate without using an ink such as a white ink. When an ink is used, it is necessary to remove the solvent by evaporation, which tends to place an environmental burden on the laminate during manufacturing, but with the above configuration, the environmental burden during the manufacturing of the laminate can be reduced. When using a stretched substrate in this form, it is preferable that the laminate has a design layer on the surface of the stretched substrate that faces the first resin layer.

[0075] 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.

[0076] The stretched substrate may be, for example, a polyethylene film having a total light transmittance of 10% to 40% as measured in accordance with JIS K7375. This allows, for example, the laminate to be imparted with opacity.

[0077] The stretched substrate is a polyethylene substrate that has undergone a stretching treatment. This stretching treatment can improve, for example, the printability, heat resistance, and strength of the polyethylene substrate. Such a stretched substrate can satisfy the physical properties required for, for example, the substrate that constitutes the body of a tube container.

[0078] The stretching may be uniaxial or biaxial. In one embodiment, the stretching ratio in the longitudinal direction (MD) of the stretched substrate is preferably 2 to 10 times, more preferably 3 to 7 times. In one embodiment, the stretching ratio in the transverse direction (TD) of the stretched substrate is preferably 2 to 10 times, more preferably 3 to 7 times. When the stretching ratio is 2 times or more, for example, the rigidity, strength, and heat resistance of the polyethylene substrate can be improved, the printability of the polyethylene substrate can be improved, and the transparency of the polyethylene substrate can be improved. When the stretching ratio is 10 times or less, for example, good stretching can be performed without causing the film to break. In one embodiment, the stretched substrate is a uniaxially oriented film, more specifically, a uniaxially oriented film that has been stretched in the longitudinal direction (MD).

[0079] The stretched substrate may be subjected to the surface treatment described above. This can improve, for example, the adhesion between the stretched substrate and the layer laminated on the stretched substrate. An anchor coat layer may be formed on the surface of the stretched substrate using a conventionally known anchor coat agent.

[0080] The thickness of the stretched substrate is preferably 10 μm to 60 μm, more preferably 15 μm to 50 μm. A thickness of 10 μm or more improves rigidity and strength. A thickness of 60 μm or less improves processability.

[0081] The stretched substrate may have a single-layer structure or a multi-layer structure. Hereinafter, a stretched substrate having a multi-layer structure will also be referred to as a "stretched multi-layer substrate." A stretched multi-layer substrate is preferable from the viewpoint of improving its strength, heat resistance, and stretchability.

[0082] The stretched multilayer substrate has a multilayer structure of two or more layers. In one embodiment, the number of layers of the stretched multilayer substrate is two to seven layers, for example, three to seven layers, or three to five layers. The number of layers of the stretched multilayer substrate is preferably an odd number, for example, three, five, or seven layers. The stretched multilayer substrate has a multilayer structure, which improves the balance of rigidity, strength, heat resistance, printability, and stretchability. It is also preferable that each layer of the stretched multilayer substrate contains polyethylene as its main component.

[0083] Below, several examples of embodiments of the stretched multilayer substrate will be described. Hereinafter, a layer with a high-density polyethylene content of 80% by mass or more will be referred to as the "high-density polyethylene layer," a layer with a medium-density polyethylene content of 80% by mass or more will be referred to as the "medium-density polyethylene layer," a layer with a low-density polyethylene content of 80% by mass or more will be referred to as the "low-density polyethylene layer," a layer with a linear low-density polyethylene content of 80% by mass or more will be referred to as the "linear low-density polyethylene layer," and a layer with an ultra-low-density polyethylene content of 80% by mass or more will be referred to as the "ultra-low-density polyethylene layer."

[0084] The stretched multilayer substrate of the first embodiment comprises a high-density polyethylene layer and a medium-density polyethylene layer in this order in the thickness direction. Having a high-density polyethylene layer as the surface resin layer of the stretched substrate improves, for example, the strength and heat resistance of the stretched substrate. Having a medium-density polyethylene layer in the stretched substrate improves, for example, the stretchability of the pre-stretched laminate.

[0085] The stretched multilayer substrate of the second embodiment comprises a high-density polyethylene layer, a medium-density polyethylene layer, and a high-density polyethylene layer in this order in the thickness direction. With this configuration, for example, the strength and heat resistance of the stretched substrate can be improved, the occurrence of curl in the stretched substrate can be suppressed, and the stretchability of the pre-stretched laminate can be improved.

[0086] The stretched multilayer substrate of the third embodiment comprises a high-density polyethylene layer, a medium-density polyethylene layer, a low-density polyethylene layer, a linear low-density polyethylene layer, or an ultra-low-density polyethylene layer (for the sake of simplicity, these three layers are collectively referred to as "low-density polyethylene layer, etc."), a medium-density polyethylene layer, and a high-density polyethylene layer, in this order in the thickness direction. By having such a configuration, for example, the stretchability of the pre-stretched laminate can be improved, the strength and heat resistance of the stretched substrate can be improved, and the occurrence of curl in the stretched substrate can be suppressed.

[0087] Other embodiments of stretched multilayer substrates include a stretched substrate comprising a high-density polyethylene layer, a high-density polyethylene layer, a blend layer of medium-density polyethylene and high-density polyethylene, a high-density polyethylene layer, and a high-density polyethylene layer in this order in the thickness direction; and a stretched substrate comprising a medium-density polyethylene layer, a high-density polyethylene layer, a linear low-density polyethylene layer, a high-density polyethylene layer, and a medium-density polyethylene layer in this order in the thickness direction.

[0088] Another example is a stretchable substrate having a high-density polyethylene layer, a blend layer of high-density polyethylene and medium-density polyethylene, a low-density polyethylene layer, a blend layer of high-density polyethylene and medium-density polyethylene, and a high-density polyethylene layer in this order in the thickness direction.

[0089] The stretched multilayer substrate of the fourth embodiment comprises a medium-density polyethylene layer, a high-density polyethylene layer, a blended layer of medium-density polyethylene and high-density polyethylene, a high-density polyethylene layer, and a medium-density polyethylene layer, in this order in the thickness direction. With this configuration, for example, the printability of the stretched substrate can be improved, the strength and heat resistance can be improved, and the stretchability of the pre-stretched laminate can be improved.

[0090] The stretched multilayer substrate of the fifth embodiment comprises, in the thickness direction, a medium-density polyethylene layer, a medium-density polyethylene layer, a blend layer of medium-density polyethylene and linear low-density polyethylene, a medium-density polyethylene layer, and a medium-density polyethylene layer. With this configuration, for example, the printability of the stretched substrate can be improved, the strength and heat resistance can be improved, and the stretchability of the pre-stretched laminate can be improved.

[0091] The stretched multilayer substrate of the sixth embodiment comprises, in the thickness direction, a blend layer of medium-density polyethylene and high-density polyethylene, a blend layer of medium-density polyethylene and linear low-density polyethylene, a linear low-density polyethylene layer, a blend layer of medium-density polyethylene and linear low-density polyethylene, and a blend layer of medium-density polyethylene and high-density polyethylene. With this configuration, for example, the printability of the stretched substrate can be improved, the strength and heat resistance can be improved, and the stretchability of the pre-stretched laminate can be improved.

[0092] The stretched multilayer substrate of the seventh embodiment comprises, in the thickness direction, a blend layer of high-density polyethylene and medium-density polyethylene, a medium-density polyethylene layer, a blend layer of linear low-density polyethylene and medium-density polyethylene, a medium-density polyethylene layer, and a blend layer of high-density polyethylene and medium-density polyethylene. With this configuration, for example, the printability of the stretched substrate can be improved, the strength and heat resistance can be improved, and the stretchability of the pre-stretched laminate can be improved.

[0093] The stretched multilayer substrate of the eighth embodiment comprises, in the thickness direction, a first layer containing medium-density polyethylene and high-density polyethylene, a second layer containing high-density polyethylene, a third layer containing linear low-density polyethylene, a fourth layer containing high-density polyethylene, and a fifth layer containing medium-density polyethylene and high-density polyethylene, in this order. The second and fourth layers may each independently further contain low-density polyethylene. This further improves the balance of heat resistance, rigidity, and processability of the stretched substrate. The third layer may further contain low-density polyethylene.

[0094] The thickness of the second and fourth layers may be independently 0.5 μm to 15 μm, 1 μm to 10 μm, or 1 μm to 8 μm. This can further improve the heat resistance of the stretched substrate. The thickness of the third layer may be 1 μm to 50 μm, 2 μm to 40 μm, or 5 μm to 30 μm. This can further improve the balance between heat resistance, rigidity, and stretchability.

[0095] In the stretched multilayer substrates of the fourth to eighth embodiments, the thickness of each of the two surface resin layers may be independently 0.5 μm to 10 μm, 1 μm to 8 μm, or 1 μm to 5 μm. This can, for example, further improve the heat resistance and printability of the stretched substrate. In the stretched multilayer substrates of the fourth to eighth embodiments, it is preferable that the thickness of each of the two surface resin layers is smaller than the total thickness of the three inner layers (multilayer intermediate layers). The ratio of the thickness of each of the two surface resin layers to the total thickness of the multilayer intermediate layers (surface resin layer / multilayer intermediate layer) may be 0.05 to 0.8, 0.1 to 0.7, or 0.1 to 0.4. This can, for example, further improve the rigidity, strength, and heat resistance of the stretched substrate.

[0096] At least one layer selected from each layer constituting the stretched multilayer substrate may contain a slip agent. This can improve the processability of the stretched substrate, for example. For example, in the stretched multilayer substrate of the eighth embodiment described above, the third layer may contain a slip agent, or all of the first to fifth layers may contain a slip agent. Examples of slip agents include amide lubricants, fatty acid esters such as glycerin fatty acid esters, hydrocarbon waxes, higher fatty acid waxes, metal soaps, hydrophilic silicones, silicone-modified (meth)acrylic resins, silicone-modified epoxy resins, silicone-modified polyethers, silicone-modified polyesters, block-type silicone (meth)acrylic copolymers, polyglycerol-modified silicones, and paraffins. Among slip agents, amide lubricants are preferred. Examples of amide lubricants include saturated fatty acid amides, unsaturated fatty acid amides, substituted amides, methylolamides, saturated fatty acid bisamides, unsaturated fatty acid bisamides, fatty acid ester amides, and aromatic bisamides. Among these, unsaturated fatty acid amides are preferred, and erucic acid amides are more preferred.

[0097] In a stretched multilayer substrate, the slip agent content in the layer containing the slip agent may be, for example, 0.01% by mass or more and 3% by mass or less, or 0.03% by mass or more and 1% by mass or less. This can further improve the processability of the stretched substrate.

[0098] The stretched multilayer substrate may include the gas barrier resin layer described above. By including the gas barrier resin layer in the stretched multilayer substrate, barrier properties such as oxygen barrier and water vapor barrier properties in the laminate can be improved without using dissimilar materials such as vapor-deposited film or aluminum foil. Such a stretched multilayer substrate may include a polyethylene layer and a gas barrier resin layer. For example, it may include a first polyethylene layer, a first adhesive resin layer, a gas barrier resin layer, a second adhesive resin layer, and a second polyethylene layer in this order. For example, it may include a substrate with 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, or a substrate with 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. Details of the polyethylene layer, adhesive resin layer, and gas barrier resin layer such as the ethylene-vinyl alcohol copolymer layer are as described above for the second resin layer including the gas barrier resin layer.

[0099] Stretched substrates can be manufactured, for example, by forming a film of polyethylene or a polyethylene composition using an inflation method or a T-die method, and then stretching it. Stretched multilayer substrates can be manufactured, for example, by forming a laminate by forming multiple films of polyethylene or polyethylene compositions using an inflation method or a T-die method, and then stretching the resulting laminate. Stretching improves the transparency, rigidity, strength, and heat resistance of the polyethylene layer, making the stretched substrate suitable for use, for example, as a base material for packaging materials. Stretching can also be performed in conjunction with inflation film forming machines.

[0100] In one embodiment, the stretched multilayer substrate is a co-extruded resin film, and each layer constituting the stretched multilayer substrate is a co-extruded resin layer. The co-extruded resin film can be manufactured, for example, by forming a film using the inflation method or the T-die method.

[0101] In one embodiment, a stretched multilayer substrate is obtained by stretching a laminate (precursor) having a multilayer structure. Specifically, the resin material constituting each layer can be co-extruded into a tubular shape to form a film and then the laminate can be manufactured. Alternatively, the resin material constituting each layer can be co-extruded into a tubular shape, and then the opposing layers can be pressed together with rubber rolls or the like to manufacture the laminate. By manufacturing the laminate in this way, the number of defective products can be significantly reduced and production efficiency can be improved.

[0102] <Other substrates (intermediate substrates)> The laminate of this disclosure may further include another substrate (intermediate substrate) between the first resin layer and the second resin layer, for example, between the second extruded resin layer and the second resin layer. The other substrate mainly contains polyethylene. An example of the other substrate is the co-extruded resin film described as the second resin layer having a gas barrier resin layer. The co-extruded resin film can adopt the same configuration as the second resin layer having a gas barrier resin layer. As the second resin layer having a gas barrier resin layer has been described above, a detailed explanation is omitted in this section.

[0103] <Design layer> The laminate of this disclosure comprises a design layer, such as a printed layer. The laminate of this disclosure may have the design layer on one or both surfaces of the stretched substrate. The design layer may be provided on the surface of the stretched substrate facing the first resin layer, or on the surface of the stretched substrate facing the second resin layer. The design layer is usually in contact with the stretched substrate.

[0104] In one embodiment, the laminate of the present disclosure comprises a printed substrate having a stretched substrate and a printed layer provided on at least one surface of the stretched substrate.

[0105] The design layer includes an image. Examples of images include letters, figures, patterns, symbols, and combinations thereof. The image may also include textual information such as the product name, the name of the contents in the packaging container, the manufacturer, and the names of the raw materials. The image may be a solid color (a so-called solid image).

[0106] The design layer contains, for example, colorants and resin components. The design layer is formed using resin compositions such as thermoplastic resin compositions, thermosetting resin compositions, and energy-ray curable resin compositions, each containing a coloring agent. The design layer contains, for example, a resin component such as a thermoplastic resin, a cured product of a thermosetting resin, or a cured product of an energy-ray curable resin, and a coloring agent.

[0107] The thermoplastic resin composition contains a thermoplastic resin and a colorant. 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 also 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. A thermosetting resin composition is, for example, a so-called thermosetting ink. 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 also contain the above-mentioned additives.

[0109] The energy ray-curable resin composition contains a compound having an energy ray-curable functional group (hereinafter also referred to as "energy ray-curable compound") and a colorant, and is a composition that cures upon irradiation with energy rays. The energy ray-curable resin composition is, for example, a so-called ultraviolet curable ink, and preferably a (meth)acrylic ultraviolet curable ink.

[0110] Examples of the energy rays include electromagnetic waves such as ultraviolet rays, infrared rays, X-rays, and γ-rays; and charged particle beams such as electron beams, proton beams, and neutron beams. Among these, ultraviolet rays are preferred from the viewpoints of curing speed, availability of irradiation sources, and price. Examples of the ultraviolet irradiation sources include mercury lamps, high-pressure mercury lamps, ultra-high-pressure mercury lamps, xenon lamps, metal halides, and LEDs. The irradiation amount of ultraviolet rays is, for example, 5 mJ / cm 2 or more and 5,000 mJ / cm 2 or less.

[0111] Examples of the energy ray-curable functional group include ethylenically unsaturated groups such as (meth)acryloyl group, vinyl group, and allyl group; and epoxy group and oxetanyl group.

[0112] Examples of the energy ray-curable compound include compounds having an ethylenically unsaturated group. Compounds having two or more ethylenically unsaturated groups are preferred, and polyfunctional (meth)acrylate compounds are preferred. As the polyfunctional (meth)acrylate compound, either a monomer or an oligomer can be used.

[0113] 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.

[0114] The polyfunctional (meth)acrylate monomer may have a modified molecular skeleton; for example, monomers modified with ethylene oxide, propylene oxide, caprolactone, and isocyanuric acid can be used.

[0115] Examples of polyfunctional (meth)acrylate oligomers include polyester (meth)acrylate, urethane (meth)acrylate, epoxy (meth)acrylate, and polyether (meth)acrylate.

[0116] 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.

[0117] Examples of photopolymerization initiators include acetophenones, benzophenones, thioxanthones, α-hydroxyalkylphenones, Michler ketones, benzoin, benzyldimethylketal, benzoylbenzoate, and α-acyloxime esters.

[0118] 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.

[0119] 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 design layer may be a high-luminosity layer having a high metallic luster.

[0120] The resin component content in the design layer may be 10% by mass or more and 99% by mass or less, 30% by mass or more and 97% by mass or less, or 50% by mass or more and 95% by mass or less. The colorant content in the design layer may be 1% by mass or more and 90% by mass or less, 3% by mass or more and 70% by mass or less, or 5% by mass or more and 50% by mass or less.

[0121] Compositions for design layers may contain organic solvents or water from the viewpoint of improving applicability, etc. 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.

[0122] For example, a design layer can be formed by applying and drying a design layer composition onto a stretched substrate, then heating it to the temperature required for curing in the case of a thermosetting resin composition, or by irradiating it with energy rays in the case of an energy-ray curable resin composition. If the design layer composition does not contain organic solvents or water, drying is not necessary.

[0123] Methods for forming the design layer include, for example, letterpress printing, flexographic printing, gravure printing, offset printing, screen printing, inkjet printing, and thermal transfer printing. When forming the design layer by letterpress printing or flexographic printing, it is preferable to use an energy-ray curable resin composition, and more preferably an ultraviolet-curable resin composition. The design layer may contain, for example, a sublimation dye. The design layer of this embodiment can be formed, for example, by sublimation transfer printing using a thermal transfer sheet.

[0124] The thickness of the design layer is preferably 0.01 μm to 30 μm, more preferably 0.5 μm to 10 μm, and even more preferably 1 μm to 5 μm. <Extruded resin layer> The laminate of this disclosure comprises a first extruded resin layer mainly containing polyethylene between a first resin layer and a stretched substrate. The laminate of this disclosure comprises a second extruded resin layer mainly containing polyethylene between a stretched substrate and a second resin layer. The extruded resin layer functions as an adhesive layer between the two. If the laminate further comprises other substrates, the laminate may further comprise a third extruded resin layer.

[0125] The laminate of this disclosure, by comprising an extruded resin layer containing polyethylene as the main component as the adhesive layer, can further improve the interlayer adhesion strength in a monomaterial laminate compared to when an adhesive is used. For example, the stretched substrate described above can be used as a substrate constituting a printing substrate. Furthermore, it can suppress the decrease in interlayer adhesion strength after the contents have been stored in the packaging container. In addition, since multiple components (e.g., a stretched substrate and a sealant film) can be laminated by extrusion lamination, process control becomes simpler.

[0126] By providing the laminate of this disclosure with an extruded resin layer containing polyethylene as the main component as the adhesive layer, the polyethylene content in the laminate can be increased compared to when using conventional non-polyethylene adhesives (e.g., two-component curing polyurethane adhesives). This improves the recyclability of the laminate.

[0127] The extruded resin layer contains polyethylene as its main component. Details of the polyethylene are as described above. The polyethylene in the extruded resin layer and the polyethylene contained in the first and second resin layers may be the same or different.

[0128] In the laminate of this disclosure, from the viewpoint of adhesion, low-density polyethylene, linear low-density polyethylene, and ultra-low-density polyethylene are preferred as the polyethylene constituting the extruded resin layer, and low-density polyethylene and linear low-density polyethylene are more preferred. As the polyethylene, biomass polyethylene or mechanically or chemically recycled polyethylene may be used.

[0129] The melt flow rate (MFR) of the polyethylene constituting the extruded resin layer is preferably 0.1 g / 10 min to 50 g / 10 min, more preferably 0.2 g / 10 min to 30 g / 10 min, and even more preferably 3.0 g / 10 min to 20 g / 10 min, from the viewpoint of film-forming properties and processability. The MFR of polyethylene is measured by Method A in accordance with JIS K7210, under conditions of a temperature of 190°C and a load of 2.16 kg.

[0130] The melting point (Tm) of the polyethylene constituting the extruded resin layer is preferably 100°C to 140°C, more preferably 100°C to 130°C, and even more preferably 100°C to 120°C, from the viewpoint of balancing heat resistance and adhesiveness. The Tm of polyethylene is obtained by differential scanning calorimetry (DSC) in accordance with JIS K7121.

[0131] The polyethylene content in the extruded resin 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.

[0132] In the laminate of this disclosure, the thickness of the extruded resin layers, such as the first extruded resin layer, the second extruded resin layer, and the third extruded resin layer, is preferably 5 μm to 40 μm, and more preferably 10 μm to 30 μm, respectively. This improves, for example, adhesion and recyclability.

[0133] The extruded resin layer can be formed, for example, by melting polyethylene or a polyethylene composition and extruding it onto a stretched substrate. The melting temperature at this time is, for example, 280°C to 340°C, preferably 290°C to 335°C.

[0134] In this disclosure, as a method for laminating a stretched substrate or other substrate with a film as a first or second resin layer, for example, a melt extrusion lamination method using a molten resin mainly containing polyethylene, particularly a sand lamination method, can be used. This makes it possible to increase the polyethylene content of the laminate. Furthermore, compared to laminating them by, for example, dry lamination, the time required for the drying and aging processes can be reduced, and therefore the production efficiency of the laminate can be improved.

[0135] <Anchor Coat Layer> The laminate of this disclosure may further include an anchor coat layer between any layers, such as between the design layer and the extruded resin layer, or between the stretched substrate and the extruded resin layer. This can improve, for example, the interlayer adhesion in the laminate. The anchor coat layer is formed, for example, by an anchor coat agent. In this embodiment, the extruded resin layer is in contact with the anchor coat layer.

[0136] Examples of anchor coating agents include polyurethane-based, polyolefin-based, polyethyleneimine-based, or epoxy resin-based anchor coating agents. In one embodiment, the anchor coating agent is a two-component curing resin, for example, consisting of a polyol as the main component and a polyisocyanate as the curing agent.

[0137] Examples of polyols include polyether polyols, polyester polyols, and (meth)acrylic polyols. Examples of polyisocyanates include aromatic polyisocyanates such as tolylene diisocyanate, xylylene diisocyanate, diphenylmethane diisocyanate, and polymethylene polyphenylene polyisocyanate, as well as aliphatic polyisocyanates such as hexamethylene diisocyanate and isophorone diisocyanate.

[0138] In one embodiment, the anchor coat layer consists of a polyurethane obtained by the reaction of a polyol with a polyisocyanate. Specific examples of polyurethanes include polyether polyurethane, polyester polyurethane, and poly(meth)acrylic polyurethane.

[0139] The anchor coat layer can be formed, for example, by applying an anchor coat agent to the design layer forming surface of a stretched substrate. The anchor coat agent can be applied by coating methods such as the roll coating method, gravure roll coating method, and kiss coating method, or by printing methods.

[0140] The thickness of the anchor coat layer is preferably 0.05 μm or more and 3.0 μm or less, more preferably 0.1 μm or more and 2.0 μm or less, and even more preferably 0.2 μm or more and 1.0 μm or less.

[0141] <Laminate structure> In one embodiment, the laminate of the present disclosure comprises a stretched substrate between a first resin layer and a second resin layer, for example, a first resin layer, a first extruded resin layer, a printing substrate, a second extruded resin layer, and a second resin layer in this order.

[0142] In one embodiment, the laminate of the present disclosure may include two or more stretched substrates between the first resin layer and the second resin layer, for example, a printing substrate and a stretched substrate. In this case, the laminate includes an extruded resin layer between each substrate. For example, the laminate comprises a first resin layer, a first extruded resin layer, a printing substrate, a second extruded resin layer, a stretched substrate, a third extruded resin layer, and a second resin layer in this order.

[0143] In one embodiment, the laminate of the present disclosure may include, between the first resin layer and the second resin layer, a stretched substrate and another substrate, such as a co-extruded resin film described as a second resin layer having a gas barrier resin layer. In this case, the laminate includes an extruded resin layer between each substrate. For example, the laminate comprises, in this order, a first resin layer, a first extruded resin layer, a printing substrate, a second extruded resin layer, a co-extruded resin film having a gas barrier resin layer, a third extruded resin layer, and a second resin layer.

[0144] A specific example of the configuration of the laminate described herein is given below. • A first resin layer / a first extruded resin layer / an anchor coat layer / a printing substrate (printing layer / stretched substrate) / a second extruded resin layer / a second resin layer which may include a gas barrier resin layer. • A first resin layer / a first extruded resin layer / a printing substrate (stretched substrate / printing layer) / an anchor coat layer / a second extruded resin layer / a second resin layer which may include a gas barrier resin layer. • First resin layer / First extruded resin layer / Anchor coat layer / Printing substrate (Printing layer / Stretched substrate) / Anchor coat layer / Second extruded resin layer / Co-extruded resin film with gas barrier resin layer / Third extruded resin layer / Second resin layer • First resin layer / First extruded resin layer / Anchor coat layer / Printing substrate (stretched substrate / Printing layer) / Anchor coat layer / Second extruded resin layer / Co-extruded resin film with gas barrier resin layer / Third extruded resin layer / Second resin layer The " / " indicates the space between each layer. Printed substrate (stretched substrate / printed layer) means that the stretched substrate faces the first resin layer and the printed layer faces the second resin layer. Printed substrate (printed layer / stretched substrate) means that the stretched substrate faces the second resin layer and the printed layer faces the first resin layer.

[0145] [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 7 is a simplified diagram showing the configuration of the tube container 20, and Figure 8 is a cross-sectional view AA of Figure 7. As shown in Figure 7, the tube container body 21 comprises a head portion 22 and a body portion 23, the body portion 23 being made of the laminate of this disclosure.

[0146] <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.

[0147] In one embodiment, the head is made of 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. Biomass polyethylene, or mechanically or chemically recycled polyethylene may be used as the polyethylene.

[0148] The above resin composition may contain the above additives.

[0149] 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.

[0150] When manufacturing a tube container body using a compression molding method, the body is attached to a male mold having a protrusion at the top, the male and female molds are placed opposite each other, and molten resin composition is supplied into the male and female molds and compressed to form the head, and the head is joined to one of the openings of the body, thereby manufacturing a tube container body comprising a head and a body.

[0151] When manufacturing a tube container body using injection molding, the body is attached to a male mold having a protrusion at the top, the male and female molds are placed opposite each other, molten resin composition is supplied from the gate, and the head is formed by injection molding. The head is then joined to one of the openings in the body, thereby manufacturing a tube container body comprising a head and a body.

[0152] <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 resin layer side surface of one end of the laminate of the present disclosure with the second resin 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 cylindrically rolled laminate.

[0153] Examples of conventional heat sealing methods include bar seals, rotary roll seals, belt seals, impulse seals, high-frequency seals, ultrasonic seals, and flame seals.

[0154] In one embodiment, a cylindrical body is manufactured by overlapping the laminate of the present disclosure so that the first resin layer surface at one end and the second resin layer surface 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 resin layer and the other end is the second resin layer. In this case, the first resin layer and the second resin layer are melted and joined together, forming a welded portion.

[0155] In the above description, the welded portion is formed by overlapping, but the same surfaces at both ends of the laminate may also be butted together and the second resin layers heat-sealed to join them. In this case, a joining tape may be applied to the outer surface of the body so as to cover the joint. The joining tape may be provided on both the inner and outer surfaces of the body.

[0156] [Tube container] The tube container of this disclosure will be described below with reference to the drawings. As shown in Figure 7, the tube container 20 of this disclosure comprises a tube container body 21 and a cap 26 attached to the head 22.

[0157] <Tube container body> As the tube container itself has been described above, it will not be described here.

[0158] <Cap> The cap is detachably attached to the dispensing opening at the top of the dispenser and serves to close the dispensing opening.

[0159] In one embodiment, the cap is made of a resin composition containing a thermoplastic resin. Examples of thermoplastic resins include polyolefins such as polyethylene and 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. As polyethylene, biomass polyethylene, or mechanically or chemically recycled polyethylene may be used.

[0160] The above resin composition may contain the above additives.

[0161] As shown in Figure 7, the cap may be a screw-type cap with a groove on its inner surface that screws onto the threads 27 of the dispensing port 25, or it may be a cap-type cap that is fitted by pressing it into the dispensing port 25.

[0162] This disclosure relates, for example, to the following [1] to

[15] . [1] A laminate comprising at least a first resin layer, a first extruded resin layer, a stretched substrate, a second extruded resin layer, and a second resin layer, wherein the laminate further comprises a design layer on the surface of the stretched substrate facing the first extruded resin layer and / or on the surface facing the second extruded resin layer, and the first resin layer, the first extruded resin layer, the stretched substrate, the second extruded resin layer, and the second resin layer each contain polyethylene as a main component. [2] The laminate according to [1], wherein at least one selected from the stretched substrate and the second resin layer comprises a gas barrier resin layer. [3] The laminate according to [1] or [2], wherein at least one selected from the stretched substrate and the second resin layer comprises a polyethylene layer and a gas barrier resin layer. [4] The laminate according to any one of [1] to [3], wherein at least one selected from the stretched substrate and the second resin layer comprises a first polyethylene layer, a first adhesive resin layer, a gas barrier resin layer, a second adhesive resin layer, and a second polyethylene layer. [5] The laminate according to any one of [2] to [4], wherein the gas barrier resin layer contains a gas barrier resin, and the content ratio of the gas barrier resin in the second resin layer is 1% by mass or more and 30% by mass or less. [6] The laminate according to any one of [1] to [5], wherein the first resin layer and the second resin layer each independently contain at least one selected from medium-density polyethylene, low-density polyethylene and linear low-density polyethylene. [7] The laminate according to any one of [1] to [6], wherein at least one selected from the stretched substrate and the second resin layer is a polyethylene film having a total light transmittance of 10% or more and 40% or less (measured in accordance with JIS K7375). [8] The laminate according to any one of [1] to [7], wherein the stretched substrate is a uniaxially stretched polyethylene substrate containing at least one selected from medium-density polyethylene and high-density polyethylene. [9] The laminate according to [1], wherein the laminate further comprises an intermediate substrate and a third extruded resin layer between the second extruded resin layer and the second resin layer, the intermediate substrate comprising a polyethylene layer and a gas barrier resin layer, and the third extruded resin layer mainly contains polyethylene.

[10] The laminate according to any one of [1] to [9], wherein the polyethylene content in the entire laminate is 90% by mass or more.

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

[10] .

[12] 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 made of a laminate according to any of [1] to

[11] above.

[13] The tube container body according to

[12] , wherein the head is made of a resin composition containing polyethylene.

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

[12] or

[13] above and a cap.

[15] The tube container according to

[14] , wherein the cap is made of a resin composition containing polyethylene. [Examples]

[0163] 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.

[0164] [Fabrication of stretched substrates] The polyethylene used in the preparation of the stretched substrate is described below. • Medium-density polyethylene (hereinafter referred to as "MDPE"): Product name Enable4002MC Density: 0.940g / cm 3 Melting point: 128℃, MFR: 0.25g / 10min ExxonMobil Corporation • High-density polyethylene (1) (hereinafter referred to as "HDPE(1)"): Product name: Elite5960G Density: 0.960g / cm 3 Melting point: 134℃, MFR: 0.8g / 10min Manufactured by Dowchemical Corporation • High-density polyethylene (2) (hereinafter referred to as "HDPE(2)"): Product name H619F Density: 0.965g / cm 3 Melting point: 135℃, MFR: 0.7g / 10min SCG Corporation • Linear low-density polyethylene (hereinafter referred to as "LLDPE"): Product name: Exceed XP8656ML Density: 0.916g / cm 3 Melting point: 121℃, MFR: 0.5g / 10min ExxonMobil Corporation • Low-density polyethylene (hereinafter referred to as "LDPE"): Product name LD2420F Density: 0.922g / cm 3 Melting point: 112℃, MFR: 0.75g / 10min Made by PTT • Contains slip-resistant MB: Product name SLIP61 10061-K Density: 0.910g / cm 3 , MFR:10g / 10min, Polyethylene-based, containing 5% by mass of erucic acid amide-based slip agent. Manufactured by Ampacet

[0165] Blended polyethylene A1 (hereinafter referred to as "Blended PE (A1)") was obtained by mixing 70 parts of MDPE and 30 parts of HDPE(1). Blended polyethylene B1 (hereinafter referred to as "Blended PE (B1)") was obtained by mixing 70 parts of HDPE(2) and 30 parts of LDPE. Blended polyethylene C1 (hereinafter referred to as "Blended PE (C1)") was obtained by mixing 98 parts of LLDPE and 2 parts of slip agent-containing MB.

[0166] Blended PE(A1), Blended PE(B1), and Blended PE(C1) were co-extruded in five layers by inflation molding with the layer thickness ratio of Blended PE(A1) layer (15 μm) / Blended PE(B1) layer (22.5 μm) / Blended PE(C1) layer (50 μm) / Blended PE(B1) layer (22.5 μm) / Blended PE(A1) layer (15 μm) to form a tubular film with a total thickness of 125 μm. The tubular film was folded at the nip and stacked into two layers. The numbers in parentheses indicate the layer thickness. The polyethylene film prepared above was stretched in the longitudinal direction (MD) at a stretching ratio of 5 times, and then the Blended PE(A1) layer (surface layer) on one side was subjected to corona discharge treatment, and the ends were slit to separate it into two pieces.

[0167] As described above, a uniaxially oriented polyethylene multilayer substrate with a thickness of 25 μm was obtained. The haze of the stretched multilayer substrate was measured in accordance with JIS K7136 and was found to be 5.6%.

[0168] [Preparation of EVOH-containing polyethylene film] Linear low-density polyethylene (Dow Chemical, DOWLEX2045G, density 0.920 g / cm³) 3 ) and adhesive resin (Mitsui Chemicals, Admer NF557) and ethylene-vinyl alcohol copolymer (Kuraray, EVAL H171B, density 1.17 g / cm³) 3 , ethylene content 38 mol%, adhesive resin (Mitsui Chemicals, Admer NF557), and linear low-density polyethylene (Dow Chemical, DOWLEX2045G, density 0.920 g / cm³) 3 ) and were co-extruded in five layers by inflation to obtain EVOH-containing polyethylene films with a thickness of 170 μm or 75 μm. In these films, the thickness of the ethylene-vinyl alcohol copolymer layer was approximately 10% of the total film thickness, and the thickness of the linear low-density polyethylene layer was approximately 40% in each case.

[0169] [Polyethylene film] The following polyethylene film was used. • 100 μm or 80 μm thick polyethylene film containing antistatic agent 1 (polyethylene (density: 0.931 g / cm³) 3 (MFR: 2.1g / 10min) and a mixture of antistatic agents are used to form a film. • 100 μm thick polyethylene film 2 (polyethylene (density: 0.931 g / cm³) 3 A film is formed from a mixture of (MFR: 2.1g / 10min) and a white pigment, resulting in a milky white film with a total light transmittance of approximately 20%. • 130 μm thick polyethylene film containing antistatic agent 3 (polyethylene (density: 0.920 g / cm³) 3 (MFR: 1.9g / 10min) and a mixture of antistatic agents are used to form a film. • 130μm thick polyethylene film 4 (polyethylene (density: 0.920g / cm³) 3 A film is formed from a mixture of (MFR: 1.9g / 10min) and a white pigment, resulting in a milky white film with a total light transmittance of approximately 20%.

[0170] [Example 1] A uniaxially oriented high-density polyethylene film (Hybron SMKQW, milky white grade, manufactured by Tokyo Ink Co., Ltd.) with a thickness of 25 μm was used as the stretched substrate. A urethane-based gravure ink (NEW-LP Super, manufactured by Toyo Ink Co., Ltd.) was applied to the stretched substrate by gravure printing and dried to form a 1 μm thick printed layer. In this way, a printing substrate was obtained.

[0171] Each layer was laminated onto the printing substrate using a tandem extrusion laminating machine. Specifically, on the side of the printing substrate opposite to the surface where the printing layer was formed, high-pressure low-density polyethylene (Novatec LD LC602A, manufactured by Nippon Polyethylene, density: 0.919 g / cm³) melted at 335°C was laminated. 3A 20 μm thick extruded resin layer was formed by extruding (LDPE) with a melting point of 107°C and an MFR of 8.2 g / 10 min. A 170 μm thick EVOH-containing polyethylene film was then laminated on this extruded resin layer. Next, an anchor coating agent (Toyo Morton, EL510 / CAT-RT80, diluent: ethyl acetate) was applied to the printing layer formation surface of the printing substrate to a thickness of 1 μm after drying, and then dried. On this coated surface, the high-pressure low-density polyethylene (LC602A) melted at 335°C was extruded to form a 20 μm thick extruded resin layer, and a 100 μm thick antistatic agent-containing polyethylene film 1 was then laminated on this extruded resin layer. In this way, a laminate was obtained.

[0172] The laminate comprises, in order, an antistatic agent-containing polyethylene film 1 (100 μm) (outermost layer), an extruded resin layer (20 μm), an anchor coat layer (1 μm), a printed layer (1 μm), a uniaxially oriented high-density polyethylene film (Hybron SMKQW, 25 μm), an extruded resin layer (20 μm), and an EVOH-containing polyethylene film (170 μm) (innermost layer).

[0173] [Example 2] A laminate was obtained in the same manner as in Example 1, except that the above-mentioned uniaxially oriented polyethylene multilayer substrate was used as the stretched substrate constituting the printing substrate, and the printing substrate was arranged so that the printing layer faced the EVOH-containing polyethylene film side.

[0174] The laminate comprises, in order, an antistatic agent-containing polyethylene film 1 (100 μm) (outermost layer), an extruded resin layer (20 μm), a uniaxially oriented polyethylene multilayer substrate (25 μm), a printed layer (1 μm), an anchor coat layer (1 μm), an extruded resin layer (20 μm), and an EVOH-containing polyethylene film (170 μm) (innermost layer).

[0175] [Example 3] Each layer was laminated onto a printing substrate using a tandem extrusion laminating machine. Specifically, the anchor coating agent was applied to the surface of the printing substrate where the printing layer would form, so that its thickness after drying was 1 μm, and then dried. On this coated surface, the high-pressure low-density polyethylene (LC602A) melted at 335°C was extruded to form an extruded resin layer with a thickness of 20 μm, and a 75 μm thick EVOH-containing polyethylene film was laminated on this extruded resin layer. Furthermore, on the film surface, the high-pressure low-density polyethylene (LC602A) melted at 335°C was extruded to form an extruded resin layer with a thickness of 20 μm, and a 100 μm thick polyethylene film 2 (milky white type) was laminated on this extruded resin layer.

[0176] The anchor coating agent was applied to the surface of the printing substrate opposite to the surface where the printing layer is formed, so that its thickness after drying was 1 μm, and then dried. On this coated surface, the high-pressure low-density polyethylene (LC602A) melted at 335°C was extruded to form an extruded resin layer with a thickness of 20 μm, and an antistatic agent-containing polyethylene film 1 with a thickness of 80 μm was laminated on this extruded resin layer. In this way, a laminate was obtained.

[0177] The laminate comprises, in order, an antistatic agent-containing polyethylene film 1 (80 μm) (outermost layer), an extruded resin layer (20 μm), an anchor coat layer (1 μm), a uniaxially oriented polyethylene multilayer substrate (25 μm), a printed layer (1 μm), an anchor coat layer (1 μm), an extruded resin layer (20 μm), an EVOH-containing polyethylene film (75 μm), an extruded resin layer (20 μm), and polyethylene film 2 (milky white type, 100 μm) (innermost layer).

[0178] [Comparative Example 1] As the 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 substrate by gravure printing and dried to form a 1 μm thick printed layer. In this way, a printing substrate was obtained.

[0179] Each layer was laminated onto the printing substrate using a tandem dry laminating machine. Specifically, a two-component urethane-based curing adhesive (manufactured by Rock Paint, solvent-type adhesive, main component: RU-004, curing agent: H-1) was applied to the surface of the printing substrate where the printing layer was formed, and dried to form an adhesive layer with a thickness of 3.0 μm. A 130 μm thick polyethylene film 4 (milky white type) was then laminated onto this adhesive layer. Next, the same two-component urethane-based curing adhesive (main component: RU-004, curing agent: H-1) was applied to the surface of the printing substrate opposite to the surface where the printing layer was formed, and dried to form an adhesive layer with a thickness of 3.0 μm. A 130 μm thick antistatic agent-containing polyethylene film 3 was then laminated onto this adhesive layer. In this way, a laminate was obtained.

[0180] The laminate comprises, in order, an antistatic agent-containing polyethylene film 3 (130 μm) (outermost layer), an adhesive layer (3.0 μm), a vapor-deposited film (IB-PET-WUB, 12 μm), a printed layer (1 μm), an adhesive layer (3.0 μm), and a polyethylene film 4 (milky white type, 130 μm) (innermost layer).

[0181] [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 to produce a cylindrical body that would become the body of the tube container. The cylindrical body was mounted on a mandrel for forming tube containers, 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). 3A tube container body was fabricated using a compression molding method with the material shown in Figure 7. The spout at the top of the obtained tube container body had an outer diameter of 30.4 mm and a height of 9.5 mm, and a spiral groove was provided on the side of the spout. The outer diameter of the shoulder portion was 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.

[0182] [Material property evaluation] <Evaluation of physical properties of tube containers (seal strength and laminate strength)> (Side seam strength) A test specimen was obtained by cutting a 15 mm wide strip from the body of the tube container perpendicular to its side seam (the part where the tube is attached). In accordance with JIS K6854-2, 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 strength at which the test specimen broke (side seam strength) was measured. (Shoulder adhesion strength) A test specimen was obtained by cutting a 15 mm wide strip from two locations on the adhesive joint between the body and shoulder of the tube container, specifically the joint where the tube is attached and the location 180° opposite, in the direction of the bottom edge. 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 peel strength at which the body separated from the shoulder was measured.

[0183] (Lamination strength) For the test specimens prepared for measuring side seam strength, the laminate strength between the printed substrate and the sealant layer (EVOH-containing polyethylene film) on the inner surface of the body was measured in the example, while the laminate strength between the printed substrate and the sealant layer (polyethylene film) on the inner surface of the body was measured in the comparative example. The average value of the laminate strength was measured under a tensile speed of 50 mm / min. A specimen was judged to pass if the initial laminate strength was 2.0 N or higher.

[0184] The above-mentioned tube containers were filled with 180g of Lux Super Rich Treatment (Unilever Japan) and 100g of Dentor Spearmint (Lion), and stored at 50°C dry for one month. The physical properties of the tube containers (seal strength and laminate strength) were measured after storage of the contents.

[0185] <Loop evaluation> A measuring device, the "LOOP STIFFNESS TESTER" manufactured by Toyo Seiki Co., Ltd., was used. The laminates obtained in the examples and comparative examples were cut to a size of 15 mm in width and 100 mm in length (flow direction during film formation: MD, direction perpendicular to the flow direction during film formation: TD), and used as measurement samples. Next, with the innermost layer of the measurement sample facing inward, both ends of the measurement sample were fixed by clipping them together, and a circular loop with a loop length of 70 mm was formed in the central part in the length direction. The resulting circular loop was pressed from the opposite side of the clip at a pressing speed of 3.3 mm / sec, and the load required to reach a load range of 5000 mN was defined as the loop stiffness value.

[0186] <Pressure resistance test> The above tube container was filled with 180g of Lux Super Rich Treatment (manufactured by Unilever Japan), and a load of 60kgf for 1 minute was applied to check for any leakage of the contents from the tube container.

[0187] <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. Furthermore, the monomaterial status of the laminates obtained in the examples and comparative examples was determined in accordance with the CEFLEX guidelines. A "○" was used to indicate compliance with the CEFLEX guidelines, and a "×" was used to indicate non-compliance.

[0188] [Table 1] [Explanation of Symbols]

[0189] 1: Laminate 2: First resin layer 4: Stretched base material 4a: Design layer 4b: Anchor coat layer 6: Second resin layer 7: Other substrates 8A: First extruded resin layer 8B: Second extruded resin layer 8C: Third extruded resin 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. It is a laminate, The aforementioned laminate, The first resin layer, A first extruded resin layer and Stretched substrate and A second extruded resin layer, A second resin layer, It has at least the following features: The laminate does not include a vapor-deposited film. The first resin layer, the first extruded resin layer, the stretched substrate, the second extruded resin layer, and the second resin layer each contain polyethylene as the main component, At least one selected from the stretched substrate and the second resin layer comprises a gas barrier resin layer. Laminated structure.

2. The laminate according to claim 1, wherein at least one selected from the stretched substrate and the second resin layer comprises a polyethylene layer and a gas barrier resin layer.

3. The laminate according to claim 1 or 2, wherein at least one selected from the stretched substrate and the second resin layer comprises a first polyethylene layer, a first adhesive resin layer, a gas barrier resin layer, a second adhesive resin layer, and a second polyethylene layer.

4. The laminate according to any one of claims 1 to 3, wherein the gas barrier resin layer contains a gas barrier resin, and the content ratio of the gas barrier resin in the second resin layer is 1% by mass or more and 30% by mass or less.

5. The laminate according to any one of claims 1 to 4, wherein the first resin layer and the second resin layer each independently contain at least one selected from medium-density polyethylene, low-density polyethylene, and linear low-density polyethylene.

6. The laminate according to any one of claims 1 to 5, wherein at least one selected from the stretched substrate and the second resin layer is a polyethylene film having a total light transmittance of 10% or more and 40% or less (measured in accordance with JIS K7375).

7. The laminate according to any one of claims 1 to 6, wherein the stretched substrate is a uniaxially stretched polyethylene substrate containing at least one selected from medium-density polyethylene and high-density polyethylene.

8. The laminate according to claim 1, wherein the laminate further comprises an intermediate substrate and a third extruded resin layer between the second extruded resin layer and the second resin layer, the intermediate substrate comprises a polyethylene layer and a gas barrier resin layer, and the third extruded resin layer contains polyethylene as the main component.

9. The laminate according to any one of claims 1 to 8, wherein the polyethylene content in the entire laminate is 90% by mass or more.

10. A laminate for forming the body of a tube container, wherein the first resin layer is a sealant layer on the outer surface of the body, and the second resin layer is a sealant layer on the inner surface of the body, according to any one of claims 1 to 9.

11. 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 the laminate described in any one of claims 1 to 10. Tube container body.

12. The tube container body according to claim 11, wherein the head portion is made of a resin composition containing polyethylene.

13. A tube container body according to claim 11 or 12, cap and A tube container equipped with the following features.

14. The tube container according to claim 13, wherein the cap is made of a resin composition containing polyethylene.

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