Laminate and tube container body

Abstract

To provide a laminate capable of preparing a tube container body having high recyclability.SOLUTION: A laminate includes a surface resin layer, a base material, a gas barrier layer and a heat seal layer. The surface resin layer, the base material and the heat seal layer are composed of the same material. The base material includes a vapor-deposited film on at least one surface thereof. The surface resin layer has heat sealability. The same material is polyethylene.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a laminate and a tube container body comprising this laminate.

[0002] A tube container, comprising a tube body and a cap, is known as a packaging container for filling with paste-like semi-liquid substances such as toothpaste or facial cleansing cream, and for dispensing them out. The tube container body generally has a cylindrical body with one end closed and the other end open, and a head with a spout connected to the other end of the body. The tube container containing the contents is manufactured by filling the body with the contents and then closing one end. Laminates made of polyethylene film, polyester film, a gas barrier layer, and aluminum foil are widely used as the body of the tube container (for example, Patent Documents 1 and 2).

[0003] In recent years, with the growing demand for a circular economy, packaging containers are required to have high recyclability. However, as mentioned above, the body of conventional tube containers is made up of a laminate consisting of layers of multiple different materials, and because it is difficult to separate each layer of different materials, it is not currently recycled. [Prior art documents] [Patent Documents]

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

[0005] The present invention has been made in view of the above problems, and an object to be solved is to provide a laminate capable of producing a tube container body having high recyclability. Another object to be solved by the present invention is to provide a tube container body including the laminate.

Means for Solving the Problems

[0006] The laminate of the present invention includes a surface resin layer, a base material, a gas barrier layer, and a heat seal layer. The surface resin layer, the base material, and the heat seal layer are made of the same material. The base material has a vapor deposition film on at least one surface. The surface resin layer has heat sealability. The same material is polyethylene, which is characterized.

[0007] In one embodiment, the laminate of the present invention includes a melt-extruded polyethylene layer or an adhesive layer in at least one of the spaces between the surface resin layer and the base material, between the base material and the gas barrier layer, and between the gas barrier layer and the heat seal layer.

[0008] In one embodiment, the polyethylene constituting the surface resin layer and the heat seal layer is low-density polyethylene and / or linear low-density polyethylene.

[0009] In one embodiment, the vapor deposition film is a metal vapor deposition film.

[0010] In one embodiment, the gas barrier layer includes a first polyethylene resin layer, a first adhesive layer, a layer containing a gas barrier resin, a second adhesive layer, and a second polyethylene resin layer.

[0011] In one embodiment, the thickness of the layer containing the gas barrier resin is 5 μm or more and 30 μm or less.

[0012] In one embodiment, the thickness of the surface resin layer and the heat-sealing layer is 50 μm or more and 150 μm or less.

[0013] In one embodiment, the thickness of the base material is 10 μm or more and 50 μm or less.

[0014] In one embodiment, the thickness of the vapor deposition film is 1 nm or more and 150 nm or less.

[0015] In one embodiment, the content of polyethylene in the entire laminate is 90% by mass or more.

[0016] In one embodiment, the laminate of the present invention is used for a tube container application.

[0017] The tube container of the present invention includes a head and a body, The head includes a shoulder connected to one end of the body and a discharge port connected to the shoulder. The body is characterized by being composed of the above laminate.

[0018] In one embodiment, the head is composed of a resin composition containing polyethylene.

[0019] In one embodiment, the tube container further includes a cap composed of a resin composition containing polyethylene.

Advantages of the Invention

[0020] According to the present invention, it is possible to provide a laminate capable of producing a tube container having high recyclability. Further, according to the present invention, it is possible to provide a tube container body having high recyclability and including the laminate.

Brief Description of the Drawings

[0021] [Figure 1] It is a schematic cross-sectional view showing one embodiment of the laminate of the present invention. [Figure 2]This is a perspective view showing one embodiment of a tube container comprising a tube container body made of the laminate of the present invention and a cap. [Figure 3] This is a cross-sectional view AA in Figure 2. [Modes for carrying out the invention]

[0022] (Laminated structure) As shown in Figure 1, the laminate 10 of the present invention comprises a surface resin layer 11, a substrate 12, a gas barrier layer 13, and a heat seal layer 14, and is characterized in that the substrate 12 has a vapor-deposited film 15 on at least one surface. The vapor-deposited film 15 is preferably provided on the surface of the substrate on the side of the surface resin layer, as this can improve the aesthetic appearance of the tube container made using the laminate of the present invention. Since the surface resin layer 11, base material 12, and heat seal layer 14 of the laminate 10 of the present invention are made of the same material, polyethylene, the laminate 10 of the present invention has high recyclability, and the tube container body equipped with this laminate also has high recyclability.

[0023] In one embodiment, as shown in Figure 1, the laminate 10 of the present invention includes at least one molten extruded polyethylene layer 16 or adhesive layer 17 between the surface resin layer 11 and the substrate 12, between the substrate 12 and the gas barrier layer 13, and between the gas barrier layer 13 and the heat seal layer 14.

[0024] In one embodiment, the substrate 12 is provided with a barrier coat layer below or above the vapor-deposited film 15 (not shown).

[0025] The polyethylene content in the entire laminate of the present invention is preferably 90% by mass or more, and more preferably 95% by mass or more. This improves the recyclability of the laminate of the present invention and the tube container equipped with the laminate.

[0026] (Surface resin layer and heat seal layer) The surface resin layer and heat seal layer constituting the laminate of the present invention are made of polyethylene and both have heat seal properties. High-density polyethylene, medium-density polyethylene, low-density polyethylene, linear low-density polyethylene, and ultra-low-density polyethylene can be used as the polyethylene. Among these, low-density polyethylene and / or linear low-density polyethylene are preferred from the viewpoint of heat sealability.

[0027] In this invention, high-density polyethylene has a density of 0.945 g / cm³. 3 The above polyethylenes can be used, and as medium-density polyethylene, the density is 0.925 g / cm³. 3 More than 0.945g / cm 3 Polyethylene with a density of less than 0.900 g / cm³ can be used, and low-density polyethylene has a density of 0.900 g / cm³. 3 More than 0.925g / cm 3 Polyethylene with a density of less than 0.900 g / cm³ can be used, and as linear low-density polyethylene, a density of 0.900 g / cm³ can be used. 3 More than 0.925g / cm 3 Polyethylene with a density of less than 0.900 g / cm³ can be used, and ultra-low density polyethylene has a density of 0.900 g / cm³. 3 Polyethylene less than a certain amount can be used.

[0028] Furthermore, in the present invention, polyethylene includes copolymers of ethylene and other monomers. Examples of ethylene copolymers include copolymers consisting 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. Also, copolymers with vinyl acetate or acrylic acid esters are acceptable as long as they do not impair the objectives of the present invention.

[0029] The surface resin layer and the heat-sealing layer can contain polyethylene derived from biomass, which is obtained by polymerizing monomers containing ethylene derived from biomass. Since such polyethylene derived from biomass is a carbon-neutral material, the environmental impact in the production of the laminate of the present invention can be reduced. Since ethylene derived from biomass is used as the monomer which is the raw material, the resulting polyethylene is derived from biomass. Note that the raw material monomer of polyethylene does not necessarily have to contain 100% by mass of ethylene derived from biomass.

[0030] The monomer which is the raw material of polyethylene derived from biomass may further contain ethylene derived from fossil fuel and / or α-olefin, or may further contain α-olefin derived from biomass.

[0031] The concentration of ethylene derived from biomass (hereinafter sometimes referred to as "biomass degree") in the polyethylene contained in the surface resin layer and the heat-sealing layer is preferably 10% or more. The "biomass degree" is a value obtained by measuring the content of carbon derived from biomass by radiocarbon (C14) measurement. Since carbon dioxide in the atmosphere contains C14 at a certain ratio (105.5 pMC), it is known that the C14 content in plants that grow by taking in carbon dioxide in the atmosphere, such as corn, is also about 105.5 pMC. It is also known that almost no C14 is contained in fossil fuels. Therefore, by measuring the ratio of C14 contained in all carbon atoms in polyethylene, the ratio of carbon derived from biomass can be calculated. In the present invention, the content of C14 in polyethylene is P C14 When it is set as, the content of carbon derived from biomass P bio can be obtained as follows. P bio (%) = P C14 / 105.5 × 100

[0032] In this invention, theoretically, if all ethylene derived from biomass is used as the raw material for polyethylene, the concentration of biomass-derived ethylene will be 100%, and the biomass content of the biomass-derived polyethylene will be 100%. Furthermore, the biomass-derived ethylene concentration in fossil fuel-derived polyethylene produced solely from fossil fuel-derived raw materials is 0%, meaning the biomass content of fossil fuel-derived polyethylene is 0%.

[0033] Biomass-derived ethylene can be produced using biomass-derived ethanol as a raw material. In particular, it is preferable to use biomass-derived fermented ethanol obtained from plant materials. The plant materials are not particularly limited, and conventionally known plants can be used. Examples include corn, sugarcane, beets, and manioc.

[0034] In this invention, biomass-derived fermented ethanol refers to ethanol produced by contacting a culture medium containing a carbon source obtained from plant raw materials with a microorganism that produces ethanol or a product derived from its crushed material, and then purifying it. Conventional known methods such as distillation, membrane separation, and extraction can be applied to purify the ethanol from the culture medium. For example, methods such as adding benzene, cyclohexane, etc., and azeotropic distillation, or removing water by membrane separation, etc., can be used.

[0035] A catalyst is usually used when obtaining ethylene by the dehydration reaction of ethanol, but this catalyst is not particularly limited, and conventionally known catalysts can be used. A fixed-bed flow reaction is advantageous in terms of process, as it allows for easy separation of the catalyst and product, and for example, γ-alumina is preferred.

[0036] Since this dehydration reaction is an endothermic reaction, it is usually carried out under heating conditions. The heating temperature is not limited as long as the reaction proceeds at a commercially useful rate, but a temperature of 100°C or higher is preferable, more preferably 250°C or higher, and even more preferably 300°C or higher. There is no particular upper limit, but from the viewpoint of energy balance and equipment, it is preferable to have a temperature of 500°C or lower, more preferably 400°C or lower.

[0037] The reaction pressure is not particularly limited, but a pressure above atmospheric pressure is preferable to facilitate subsequent gas-liquid separation. Industrially, a fixed-bed flow reaction is preferred because it facilitates catalyst separation, but a liquid-phase suspension bed or fluidized bed may also be used.

[0038] In the dehydration reaction of ethanol, the yield of the reaction depends on the amount of water contained in the ethanol supplied as a raw material. Generally, when performing a dehydration reaction, it is preferable to have no water present in order to improve the efficiency of water removal. However, in the case of the dehydration reaction of ethanol using a solid catalyst, it has been found that the amount of other olefins, especially butene, tends to increase when water is not present. This is probably because the dimerization of ethylene after dehydration cannot be suppressed without the presence of a small amount of water. The lower limit of the acceptable water content is 0.1% or more, preferably 0.5% or more. The upper limit is not particularly limited, but from the viewpoint of mass balance and heat balance, it is preferably 50% by weight or less, more preferably 30% or less, and even more preferably 20% or less.

[0039] By carrying out the dehydration reaction of ethanol in this manner, a mixture of ethylene, water, and a small amount of unreacted ethanol is obtained. However, since ethylene is a gas at room temperature and below approximately 5 MPa, water and ethanol can be removed from this mixture by gas-liquid separation to obtain ethylene. This method can be carried out using known methods.

[0040] The ethylene obtained by gas-liquid separation is further distilled, and there are no particular restrictions on the distillation method, operating temperature, or residence time, except that the operating pressure at this time is above atmospheric pressure.

[0041] When the raw material is biomass-derived ethanol, the resulting ethylene contains trace amounts of impurities introduced during the ethanol fermentation process, such as carbonyl compounds like ketones, aldehydes, and esters, as well as their decomposition products like carbon dioxide, and nitrogen-containing compounds like amines and amino acids, as well as their decomposition products like ammonia, which are enzyme decomposition products and contaminants. Depending on the application of the ethylene, these trace amounts of impurities may be problematic and may be removed by purification. The purification method is not particularly limited and can be carried out by conventionally known methods. A suitable purification operation is, for example, adsorption purification. The adsorbent used is not particularly limited and can be any conventionally known adsorbent. For example, a material with a high surface area is preferred, and the type of adsorbent is selected according to the type and amount of impurities in the ethylene obtained by the dehydration reaction of biomass-derived ethanol.

[0042] Furthermore, a caustic water treatment may be used in combination as a method for purifying impurities in ethylene. If caustic water treatment is used, it is desirable to perform it before adsorption purification. In that case, it is necessary to perform a water removal treatment after the caustic treatment and before adsorption purification.

[0043] Furthermore, the surface resin layer and heat seal layer may also contain polyethylene recycled through mechanical recycling. Mechanical recycling generally involves crushing recovered polyethylene film, washing it with alkali to remove dirt and foreign matter from the film surface, then drying it at high temperature and reduced pressure for a certain period of time to disperse contaminants remaining inside the film, thereby decontaminating the polyethylene film and returning it to polyethylene.

[0044] The surface resin layer and heat seal layer may contain additives to the extent that they do not impair the properties of the present invention, such as crosslinking agents, antioxidants, antiblocking agents, lubricants, ultraviolet absorbers, light stabilizers, fillers, reinforcing agents, antistatic agents, pigments, and modifying resins.

[0045] In one embodiment, the surface resin layer and the heat seal layer consist of a film made of polyethylene, and this film may be a stretched film or an unstretched film. From the viewpoint of heat sealability, an unstretched film is preferred.

[0046] The surface resin layer and heat seal layer may be surface-treated. This can improve adhesion with adjacent layers. The surface treatment method is not particularly limited and includes 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. Alternatively, an anchor coat layer may be formed on the surface resin layer and the heat seal layer using a conventionally known anchor coat agent.

[0047] The thickness of the surface resin layer and the heat seal layer is preferably 30 μm to 150 μm, and more preferably 50 μm to 120 μm. The thickness of the surface resin layer and the heat seal layer may be the same or different. By increasing the thickness of the surface resin layer and the heat seal layer to 30 μm or more, the heat sealability can be further improved. Furthermore, by setting the thickness of the surface resin layer and the heat seal layer to 150 μm or less, the processability of the laminate comprising the substrate can be improved.

[0048] In one embodiment, the surface resin layer and the heat seal layer can be produced by forming a film from a resin composition containing at least polyethylene using a T-die method or an inflation method. Furthermore, lamination between the surface resin layer and the substrate can be carried out via a molten extruded polyethylene layer or adhesive layer, as described later.

[0049] (base material) The substrate constituting the laminate of the present invention is made of polyethylene, and as polyethylene, high-density polyethylene, medium-density polyethylene, low-density polyethylene, linear low-density polyethylene, and ultra-low-density polyethylene can be used. Among these, high-density polyethylene and medium-density polyethylene are preferred from the viewpoint of the strength and heat resistance of the base material, and medium-density polyethylene is more preferred from the viewpoint of stretchability.

[0050] The base material may contain biomass-derived polyethylene, and it is preferable that the concentration of biomass-derived ethylene in the polyethylene contained in the base material (hereinafter sometimes referred to as "biomass content") is 10% or more.

[0051] Furthermore, the base material may also contain polyethylene recycled through mechanical recycling.

[0052] The base material may contain the above-mentioned additives to the extent that it does not impair the properties of the present invention.

[0053] In one embodiment, the substrate has a multilayer structure. For example, the structure can include a layer made of low-density polyethylene, a layer made of high-density polyethylene, and a layer made of low-density polyethylene.

[0054] In one embodiment, the substrate consists of a film made of polyethylene, and the film may be a stretched film or an unstretched film.

[0055] The substrate may be surface-treated. This can improve adhesion with adjacent layers. The surface treatment method is not particularly limited and includes 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. Alternatively, an anchor coat layer may be formed on the substrate surface using a conventionally known anchor coat agent.

[0056] The substrate may have a printed layer on its surface, and the image formed on the printed layer is not particularly limited and may represent characters, patterns, symbols, or combinations thereof. From an environmental perspective, it is preferable to use biomass-derived inks for forming the printed layer on the substrate. The method for forming the printed layer is not particularly limited and can be described as conventionally known printing methods such as gravure printing, offset printing, and flexographic printing. Among these, flexographic printing is preferred from the viewpoint of environmental impact.

[0057] The thickness of the substrate is preferably 10 μm or more and 50 μm or less, and more preferably 20 μm or more and 40 μm or less. By increasing the thickness of the base material to 10 μm or more, its strength and heat resistance can be further improved. Furthermore, by setting the thickness of the substrate to 50 μm or less, the processability of the laminate comprising the substrate can be improved.

[0058] In one embodiment, the substrate can be produced by forming a film from a resin composition containing at least polyethylene using a T-die method or an inflation method.

[0059] (Vaporized film) The substrate has a vapor-deposited film on at least one surface. This improves the gas barrier properties of the laminate, specifically the oxygen barrier and water vapor barrier properties. The vapor-deposited film is preferably provided on the gas barrier layer side surface of the substrate, as this can improve the aesthetic design of the tube container made using the laminate of the present invention.

[0060] The vapor-deposited film may be composed of a metal or an inorganic oxide, but a vapor-deposited film composed of a metal (hereinafter referred to as a metal vapor-deposited film) is preferred because it can impart a glossy appearance to tube containers and the like made using the laminate of the present invention, thereby improving their design. Examples of metals that make up a metal vapor-deposited film include aluminum, chromium, tin, nickel, copper, silver, gold, and platinum. Examples of metal oxides include aluminum oxide, silicon oxide, magnesium oxide, calcium oxide, zirconium oxide, titanium oxide, boron oxide, hafnium oxide, and barium oxide.

[0061] It is preferable that the surface of the deposited film is subjected to the above-mentioned surface treatment. This improves adhesion with adjacent layers.

[0062] The thickness of the deposited film is preferably 1 nm or more and 150 nm or less, and more preferably 5 nm or more and 60 nm or less. By increasing the thickness of the vapor-deposited film to 1 nm or more, the oxygen barrier and water vapor barrier properties of the laminate can be further improved. Furthermore, if a metal vapor-deposited film is used, a higher gloss can be imparted. By limiting the thickness of the deposited film to 150 nm or less, crack formation in the deposited film can be prevented. Furthermore, the recyclability of the laminate can be maintained.

[0063] The formation of a deposited film on a substrate can be carried out using conventionally known methods, such as physical vapor deposition (PVD) methods including vacuum deposition, sputtering, and ion plating, and chemical vapor deposition (CVD) methods including plasma chemical vapor deposition, thermochemical vapor deposition, and photochemical vapor deposition.

[0064] Furthermore, for example, a composite film consisting of two or more layers of deposited inorganic oxides can be formed and used by combining both physical vapor deposition and chemical vapor deposition methods. The vacuum level of the deposition chamber before oxygen introduction is 10 -2 ~10 -8 A bar of approximately mbar is preferred, and after oxygen introduction, 10 -1 ~10 -6 A pressure of approximately mbar is preferred. The amount of oxygen introduced will vary depending on the size of the deposition machine. Inert gases such as argon, helium, or nitrogen may be used as carrier gases for the oxygen introduced, within reasonable limits. The film transport speed can be approximately 10 to 800 m / min.

[0065] (Barrier coat layer) In one embodiment, the substrate is provided with a barrier coating layer below or above the vapor-deposited layer. This improves the oxygen barrier and water vapor barrier properties of the laminate. If the substrate includes a vapor-deposited film, the barrier coat layer may be provided on or beneath the vapor-deposited film.

[0066] In one embodiment, the barrier coat layer includes ethylene-vinyl alcohol copolymer (EVOH), polyvinyl alcohol, polyacrylonitrile, polyamides such as nylon 6, nylon 6,6 and polymethaxylylene adipamide (MXD6), polyester, polyurethane, and gas barrier resins such as (meth)acrylic resin. Among these, polyvinyl alcohol is preferred from the viewpoint of oxygen barrier properties and water vapor barrier properties. Furthermore, when the vapor-deposited film is composed of an inorganic oxide, the occurrence of cracks in the vapor-deposited film can be effectively prevented by incorporating polyvinyl alcohol into the barrier coat layer.

[0067] The gas barrier resin content in the barrier coat layer is preferably 50% by mass or more and 95% by mass or less, and more preferably 75% by mass or more and 90% by mass or less. By setting the gas barrier resin content in the barrier coat layer to 50% by mass or more, the oxygen barrier and water vapor barrier properties of the substrate can be further improved.

[0068] The barrier coating layer may contain the above-mentioned additives to the extent that they do not impair the properties of the present invention.

[0069] The thickness of the barrier coat layer is preferably 0.01 μm or more and 10 μm or less, and more preferably 0.1 μm or more and 5 μm or less. By increasing the thickness of the barrier coating layer to 0.01 μm or more, the oxygen barrier and water vapor barrier properties of the laminate can be further improved. Furthermore, by keeping the barrier coating layer thickness to 10 μm or less, the recyclability of the laminate can be maintained.

[0070] A barrier coating layer can be formed by dissolving or dispersing the above-mentioned material in water or a suitable solvent, applying it, and drying it. Alternatively, a barrier coating layer can also be formed by applying and drying a commercially available barrier coating agent.

[0071] In another embodiment, the barrier coating layer is a gas barrier coating film containing at least one resin composition, such as a hydrolyzed metal alkoxide or a hydrolyzed condensate of a metal alkoxide, obtained by polycondensation of a mixture of a metal alkoxide and a water-soluble polymer by a sol-gel method in the presence of a sol-gel catalyst, water, and an organic solvent. When the substrate comprises a vapor-deposited film made of an inorganic oxide, the occurrence of cracks in the vapor-deposited film can be effectively prevented by providing a barrier coating layer of this form adjacent to the vapor-deposited film.

[0072] In one embodiment, the metal alkoxide is represented by the following general formula. R1 n M(OR 2 ) m (However, in the formula, R 1 , R 2 (Each represents an organic group with 1 to 8 carbon atoms, M represents a metal atom, n represents a non-negative integer, m represents a non-negative integer, and n+m represents the valence of M.)

[0073] Examples of metal atoms M that can be used include silicon, zirconium, titanium, and aluminum. Also, R 1 and R 2 Examples of organic groups represented by include alkyl groups such as methyl, ethyl, n-propyl, i-propyl, n-butyl, and i-butyl groups.

[0074] Examples of metal alkoxides that satisfy the above general formula include tetramethoxysilane (Si(OCH3)4), tetraethoxysilane (mass%) Si(OC2H5)4), tetrapropoxysilane (Si(OC3H7)4), and tetrabutoxysilane (Si(OC4H9)4).

[0075] Furthermore, it is preferable to use a silane coupling agent together with the above-mentioned metal alkoxide. As silane coupling agents, known organic reactive group-containing organoalkoxysilanes can be used, but organoalkoxysilanes having an epoxy group are particularly preferred. Examples of organoalkoxysilanes having an epoxy group include γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, and β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane.

[0076] Two or more silane coupling agents may be used as described above, and it is preferable to use the silane coupling agent in an amount of about 1 to 20 parts by mass per 100 parts by mass of the total amount of the alkoxides.

[0077] As water-soluble polymers, polyvinyl alcohol and ethylene-vinyl alcohol copolymers are preferred, and from the viewpoint of oxygen barrier properties, water vapor barrier properties, water resistance and weather resistance, it is preferable to use these in combination.

[0078] The content of the water-soluble polymer in the gas barrier coating film is preferably 5 parts by mass or more and 500 parts by mass or less per 100 parts by mass of metal alkoxide. By setting the content of the water-soluble polymer in the gas barrier coating film to 5 parts by mass or more per 100 parts by mass of metal alkoxide, the oxygen barrier and water vapor barrier properties of the laminate can be further improved. Furthermore, by setting the content of the water-soluble polymer in the gas barrier coating film to 500 parts by mass or less per 100 parts by mass of metal alkoxide, the film-forming properties of the gas barrier coating film can be improved.

[0079] The thickness of the gas barrier coating film is preferably 0.01 μm to 100 μm, and more preferably 0.1 μm to 50 μm. This allows for improved oxygen barrier and water vapor barrier properties while maintaining recyclability. By setting the thickness of the gas barrier coating film to 0.01 μm or more, the oxygen barrier and water vapor barrier properties of the laminate can be improved. Furthermore, when it is provided adjacent to a vapor-deposited film composed of inorganic oxides, it can prevent the occurrence of cracks in the vapor-deposited film.

[0080] A gas barrier coating film can be formed by applying a composition containing the above-mentioned materials using conventionally known methods such as roll coating (including gravure roll coaters), spray coating, spin coating, dipping, brushing, barcode application, or applicator application, and then polycondensing the composition by a sol-gel method. Suitable catalysts for the sol-gel process include acids or amine compounds. Suitable amine compounds include tertiary amines that are substantially insoluble in water and soluble in organic solvents, such as N,N-dimethylbenzylamine, tripropylamine, tributylamine, and tripentylamine. Among these, N,N-dimethylbenzylamine is preferred. The sol-gel catalyst is preferably used in an amount of 0.01 parts by mass or more and 1.0 part by mass or less per 100 parts by mass of metal alkoxide, and more preferably in an amount of 0.03 parts by mass or more and 0.3 parts by mass or less. The catalytic effect can be improved by using 0.01 parts by mass or more of the sol-gel catalyst per 100 parts by mass of metal alkoxide. Furthermore, by using 1.0 part by mass or less of the sol-gel catalyst per 100 parts by mass of metal alkoxide, the thickness of the formed gas barrier coating film can be made uniform.

[0081] The above composition may further contain an acid. The acid is used as a catalyst for the sol-gel process, mainly as a catalyst for the hydrolysis of alkoxides and silane coupling agents. As acids, mineral acids such as sulfuric acid, hydrochloric acid, and nitric acid, as well as organic acids such as acetic acid and tartaric acid, can be used. The amount of acid used is preferably 0.001 moles or more and 0.05 moles or less relative to the total molar amount of the alkoxide and the alkoxide portion (e.g., silicate portion) of the silane coupling agent. The catalytic effect can be improved by using an amount of acid equal to 0.001 moles or more relative to the total molar amount of the alkoxide component (e.g., silicate portion) of the alkoxide and silane coupling agent. Furthermore, by limiting the amount of alkoxide (e.g., silicate portion) of the alkoxide and silane coupling agent to 0.05 moles or less relative to the total molar amount, the thickness of the formed gas barrier coating can be made uniform.

[0082] Furthermore, the above composition preferably contains water in a proportion of 0.1 moles to 100 moles, more preferably 0.8 moles to 2 moles, per mole of the total molar amount of alkoxide. By setting the water content to 0.1 moles or more per mole of the total molar amount of alkoxide, the oxygen barrier properties and water vapor barrier properties of the laminate of the present invention can be improved. Furthermore, by ensuring that the water content is 100 moles or more per mole of the total molar amount of alkoxide, the hydrolysis reaction can be carried out rapidly.

[0083] Furthermore, the above composition may contain an organic solvent. Examples of organic solvents include methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, and n-butanol.

[0084] The following describes one embodiment of a method for forming a gas barrier coating film. First, a composition is prepared by mixing a metal alkoxide, a water-soluble polymer, a sol-gel catalyst, water, an organic solvent, and, if necessary, a silane coupling agent. A polycondensation reaction gradually proceeds within this composition. Next, the composition is applied to the substrate using the conventionally known method described above and dried. This drying further promotes the polycondensation reaction between the alkoxide and the water-soluble polymer (and the silane coupling agent if the composition contains one), forming a layer of composite polymer. Finally, a gas barrier coating film can be formed by heating the composition at a temperature of 20 to 250°C, preferably 50 to 220°C, for 1 second to 10 minutes.

[0085] The barrier coat layer may have a printed layer formed on it. The method for forming the printed layer is as described above.

[0086] (Gas barrier layer) The gas barrier layer of the laminate of the present invention contains a gas barrier resin, which improves the oxygen barrier and water vapor barrier properties of the laminate. The gas barrier layer may have a single-layer structure or a multi-layer structure. If the gas barrier layer has a multi-layer structure, it is sufficient that at least one layer contains a gas barrier resin. In one embodiment, the multilayer gas barrier layer, as shown in Figure 1, is composed of a first polyethylene resin layer 13A, a first adhesive layer 13B, a layer 13C containing a gas barrier resin, a second adhesive layer 13D, and a second polyethylene resin layer 13E. The adhesive layer will be discussed later.

[0087] Examples of gas barrier resins include ethylene-vinyl alcohol copolymer (EVOH), polyvinyl alcohol, polyacrylonitrile, polyamides such as nylon 6, nylon 6,6 and polymethaxylylene adipamide (MXD6), polyesters, polyurethanes, and (meth)acrylic resins.

[0088] The gas barrier layer preferably contains a compatibilizer. By including a compatibilizer in the gas barrier layer, when a tube container made using the laminate of the present invention is heated, melted, and recycled, the gas barrier resin contained in the gas barrier layer and the polyethylene contained in the substrate effectively prevent a decrease in their physical properties due to uniform mixing. Furthermore, a decrease in transparency can be effectively prevented. While conventionally known compatibilizers can be appropriately selected and used, from the viewpoint of recyclability, unsaturated carboxylic acid-modified polyolefins are preferred, and among them, maleic anhydride-modified polyethylene is more preferred. If the gas barrier layer has a multilayer structure, two or more layers may contain a compatibilizer.

[0089] The content of the compatibilizer in the entire gas barrier layer is preferably 5% by mass or more and 20% by mass or less. By setting the compatibilizer content in the entire gas barrier layer to 5% by mass or more, the above-mentioned deterioration in physical properties and transparency can be prevented more effectively. By limiting the compatibilizer content in the entire gas barrier layer to 20% by mass or less, the moldability of the gas barrier layer can be improved. Furthermore, the laminate of the present invention can be recycled, and a decrease in the strength of the film produced using the resulting resin can be prevented.

[0090] Within the limits that do not impair the properties of the present invention, the gas barrier layer may contain resins other than gas barrier resins, including polyolefins such as polyethylene and polypropylene, polyesters such as polyethylene terephthalate and polyethylene naphthalate, (meth)acrylic resins, cellulose resins, and vinyl resins. Among these, polyethylene is preferred from the viewpoint of adhesion to the substrate and the recyclability of the laminate.

[0091] Furthermore, the gas barrier layer may contain the above-mentioned additives, to the extent that it does not impair the properties of the present invention.

[0092] In one embodiment, the gas barrier layer is made of a film, which may be a stretched film or an unstretched film. From the viewpoint of the strength of the laminate, a stretched film is preferred. The stretched film may be a uniaxially oriented film or a biaxially oriented film.

[0093] Furthermore, it is preferable that the gas barrier layer has the above-mentioned surface treatment applied to its surface. This improves adhesion with adjacent layers.

[0094] When the gas barrier layer has a single-layer structure, its thickness is preferably 10 μm or more and 30 μm or less, and more preferably 15 μm or more and 20 μm or less. By increasing the thickness of the gas barrier layer to 10 μm or more, the gas barrier properties of the laminate of the present invention can be improved. Furthermore, by setting the thickness of the gas barrier layer to 30 μm or less, the recyclability of the laminate of the present invention can be improved.

[0095] When the gas barrier layer has a multilayer structure, the sum of the thicknesses of the layers containing the gas barrier resin is preferably 20 μm or more and 100 μm or less, and more preferably 30 μm or more and 80 μm or less. By making the sum of the thicknesses of the layers containing the gas barrier resin 20 μm or more, the gas barrier properties of the laminate of the present invention can be improved. Furthermore, by making the sum of the thicknesses of the layers containing the gas barrier resin 100 μm or less, the recyclability of the laminate of the present invention can be improved.

[0096] In one embodiment, the gas barrier layer can be produced by forming a film from a gas barrier resin using a T-die method or an inflation method. Lamination with the base material can be carried out via a molten extruded polyethylene layer or adhesive layer, as described later.

[0097] (Melted extruded polyethylene layer) In one embodiment, the laminate of the present invention may include a molten extruded polyethylene layer between any of the layers, for example, between the surface resin layer and the substrate, between the substrate and the gas barrier layer, or between the gas barrier layer and the heat seal layer. The polyethylene used in the molten extruded polyethylene layer can be high-density polyethylene, medium-density polyethylene, low-density polyethylene, linear low-density polyethylene, or ultra-low-density polyethylene. Among these, low-density polyethylene, linear low-density polyethylene, and ultra-low-density polyethylene are preferred from the viewpoint of interlayer adhesion.

[0098] The molten extruded polyethylene layer may contain biomass-derived polyethylene, and it is preferable that the biomass-derived ethylene concentration in the polyethylene contained in the molten extruded polyethylene layer (hereinafter sometimes referred to as "biomass content") is 10% or more.

[0099] Furthermore, the molten extruded polyethylene layer may also contain polyethylene recycled through mechanical recycling.

[0100] The molten extruded polyethylene layer may contain the above-mentioned additives to the extent that it does not impair the properties of the present invention.

[0101] The thickness of the molten extruded polyethylene layer is preferably 5 μm or more and 30 μm or less, and more preferably 10 μm or more and 20 μm or less. By making the thickness of the molten extruded polyethylene layer 5 μm or more, the adhesion between layers can be further improved. Furthermore, by making the thickness of the molten extruded polyethylene layer 30 μm or less, the production cost of the laminate of the present invention can be reduced, and its productivity can be improved.

[0102] A melt-extruded polyethylene layer can be formed by melt-extruding a resin composition containing at least polyethylene onto a substrate or the like.

[0103] (adhesive layer) In one embodiment, the laminate of the present invention may include an adhesive layer between any of the layers, for example, between the surface resin layer and the substrate, between the substrate and the gas barrier layer, or between the gas barrier layer and the heat seal layer. Furthermore, the laminate of the present invention may include an adhesive layer as a layer constituting the gas barrier layer.

[0104] The adhesive layer may be formed using a conventionally known adhesive. This adhesive may be a one-component curing type, a two-component curing type, or a non-curing type. Furthermore, the adhesive may be either a solvent-free adhesive or a solvent-based adhesive, but from the standpoint of environmental impact, a solvent-free adhesive is preferable. Examples of solvent-free adhesives include polyether-based adhesives, polyester-based adhesives, silicone-based adhesives, epoxy-based adhesives, and urethane-based adhesives. Among these, two-component curing type urethane-based adhesives are preferably used. Examples of solvent-based adhesives include rubber-based adhesives, vinyl-based adhesives, silicone-based adhesives, epoxy-based adhesives, phenol-based adhesives, and olefin-based adhesives.

[0105] Furthermore, when the adhesive layer is provided adjacent to the aluminum vapor-deposited film, more specifically when the substrate has an aluminum vapor-deposited film and the adhesive layer is provided between the aluminum vapor-deposited film and the gas barrier layer, it is preferable that the adhesive layer consists of a cured product of a resin composition containing a polyester polyol and an isocyanate compound. When forming a laminate with a vapor-deposited film, bending loads are applied to the laminate by the molding machine, which may cause cracks in the aluminum vapor-deposited film. By using the above-described configuration for the adhesive layer, it is possible to prevent the occurrence of cracks in the aluminum vapor-deposited film, and even if cracks do occur, the reduction in oxygen barrier properties and water vapor barrier properties can be suppressed (bending load resistance).

[0106] Polyester polyols have two or more hydroxyl groups as functional groups in one molecule. Isocyanate compounds, on the other hand, have two or more isocyanate groups as functional groups in one molecule. Polyester polyols have, for example, a polyester structure or a polyester polyurethane structure as their main backbone.

[0107] A specific example of a resin composition (adhesive) containing polyester polyol and isocyanate compounds is the PASLIM series sold by DIC Corporation.

[0108] The resin composition may further contain a phosphate-modified compound, a plate-like inorganic compound, a coupling agent, cyclodextrin and / or its derivatives.

[0109] Examples of polyester polyols having two or more hydroxyl groups in one molecule as functional groups include the following [Example 1] to [Example 3]. [Example 1] Polyester polyol obtained by polycondensation of an ortho-oriented polycarboxylic acid or its anhydride with a polyhydric alcohol [Example 2] Polyester polyol having a glycerol skeleton [Example 3] Polyester polyol having an isocyanuric ring The following describes each type of polyester polyol.

[0110] The polyester polyol of the first example is a polycondensate obtained by polycondensing a polycarboxylic acid component containing at least one orthophthalic acid and its anhydride with a polyhydric alcohol component containing at least one selected from the group consisting of ethylene glycol, propylene glycol, butylene glycol, neopentyl glycol, and cyclohexanedimethanol. In particular, polyester polyols in which orthophthalic acid and its anhydride are present in a proportion of 70 to 100% by mass relative to the total polycarboxylic acid components are preferred.

[0111] The polyester polyol according to the first example requires orthophthalic acid and its anhydride as polycarboxylic acid components, but other polycarboxylic acid components may be copolymerized to the extent that the effects of this embodiment are not impaired. Specifically, examples include aliphatic polycarboxylic acids such as succinic acid, adipic acid, azelaic acid, sebacic acid, and dodecanedicarboxylic acid; unsaturated bond-containing polycarboxylic acids such as maleic anhydride, maleic acid, and fumaric acid; alicyclic polycarboxylic acids such as 1,3-cyclopentanedicarboxylic acid and 1,4-cyclohexanedicarboxylic acid; terephthalic acid, isophthalic acid, pyromellitic acid, trimellitic acid, 1,4-naphthalenedicarboxylic acid, 2,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, naphthalic acid, biphenyldicarboxylic acid, 1,2-bis(phenoxy)ethane-p,p'-dicarboxylic acid, anhydrides of these dicarboxylic acids, and ester-forming derivatives of these dicarboxylic acids; and polybasic acids such as p-hydroxybenzoic acid, p-(2-hydroxyethoxy)benzoic acid, and ester-forming derivatives of these dihydroxycarboxylic acids. Among these, succinic acid, 1,3-cyclopentanedicarboxylic acid, and isophthalic acid are preferred. Furthermore, two or more of the above-mentioned polycarboxylic acids may be used.

[0112] As an example of a polyester polyol related to the second example, a polyester polyol having a glycerol skeleton represented by general formula (1) can be mentioned. [ka] In general formula (1), R1, R2, and R3 are each independently H (hydrogen atom) or a group represented by the following general formula (2). [ka]

[0113] In formula (2), n represents an integer from 1 to 5, X represents an arylene group selected from the group consisting of a 1,2-phenylene group, a 1,2-naphthylene group, a 2,3-naphthylene group, a 2,3-anthraquinonediyl group, and a 2,3-anthracenediyl group, which may have substituents, and Y represents an alkylene group having 2 to 6 carbon atoms. However, at least one of R1, R2, and R3 represents a group represented by general formula (2).

[0114] In general formula (1), at least one of R1, R2, and R3 must be a group represented by general formula (2). In particular, it is preferable that all of R1, R2, and R3 are groups represented by general formula (2).

[0115] Furthermore, the compound may be a mixture of two or more compounds in which one of R1, R2, or R3 is a group represented by general formula (2), two of R1, R2, or R3 are groups represented by general formula (2), or all of R1, R2, and R3 are groups represented by general formula (2).

[0116] X represents an arylene group selected from the group consisting of a 1,2-phenylene group, a 1,2-naphthylene group, a 2,3-naphthylene group, a 2,3-anthraquinonediyl group, and a 2,3-anthracenediyl group, which may have substituents. If X is substituted by a substituent, it may be substituted by one or more substituents, the substituents being bonded to any carbon atom on X that is different from the free radical. Examples of substituents include chloro, bromo, methyl, ethyl, i-propyl, hydroxyl, methoxy, ethoxy, phenoxy, methylthio, phenylthio, cyano, nitro, amino, phthalimide, carboxyl, carbamoyl, N-ethylcarbamoyl, phenyl, and naphthyl groups.

[0117] In general formula (2), Y represents an alkylene group having 2 to 6 carbon atoms, such as an ethylene group, propylene group, butylene group, neopentylene group, 1,5-pentylene group, 3-methyl-1,5-pentylene group, 1,6-hexylene group, methylpentylene group, and dimethylbutylene group. Among these, propylene and ethylene groups are preferred, with ethylene being the most preferred.

[0118] Polyester resin compounds having a glycerol skeleton represented by general formula (1) can be synthesized by reacting glycerol with an aromatic polycarboxylic acid or its anhydride in which the carboxylic acid is substituted in the ortho position, and a polyhydric alcohol component as essential components.

[0119] Examples of aromatic polycarboxylic acids or their anhydrides in which the carboxylic acid is substituted at the ortho position include orthophthalic acid or its anhydride, naphthalene 2,3-dicarboxylic acid or its anhydride, naphthalene 1,2-dicarboxylic acid or its anhydride, anthraquinone 2,3-dicarboxylic acid or its anhydride, and 2,3-anthracenecarboxylic acid or its anhydride. These compounds may have substituents on any carbon atom of the aromatic ring. Examples of substituents include chloro, bromo, methyl, ethyl, i-propyl, hydroxyl, methoxy, ethoxy, phenoxy, methylthio, phenylthio, cyano, nitro, amino, phthalimide, carboxyl, carbamoyl, N-ethylcarbamoyl, phenyl, and naphthyl groups.

[0120] Furthermore, examples of polyhydric alcohol components include alkylenediols having 2 to 6 carbon atoms. Examples of diols include ethylene glycol, propylene glycol, butylene glycol, neopentyl glycol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, methylpentanediol, and dimethylbutanediol.

[0121] The polyester polyol in the third example is a polyester polyol having an isocyanuric ring represented by the following general formula (3). [ka] In general formula (3), R1, R2, and R3 each independently represent either "-(CH2)n1-OH (where n1 is an integer from 2 to 4)" or the structure of general formula (4). [ka]

[0122] In general formula (4), n2 represents an integer from 2 to 4, n3 represents an integer from 1 to 5, X represents an arylene group selected from the group consisting of 1,2-phenylene, 1,2-naphthylene, 2,3-naphthylene, 2,3-anthraquinonediyl, and 2,3-anthracenediyl groups, which may have substituents, and Y represents an alkylene group having 2 to 6 carbon atoms. However, at least one of R1, R2, and R3 is a group represented by general formula (4).

[0123] In general formula (3), the alkylene group represented by -(CH2)n1- may be linear or branched. n1 is preferably 2 or 3, with 2 being the most preferred.

[0124] In general formula (4), n² represents an integer between 2 and 4, and n³ represents an integer between 1 and 5. X represents an arylene group selected from the group consisting of a 1,2-phenylene group, a 1,2-naphthylene group, a 2,3-naphthylene group, a 2,3-anthraquinonediyl group, and a 2,3-anthracenediyl group, which may have substituents.

[0125] If X is substituted by a substituent, it may be substituted by one or more substituents, the substituents being bonded to any carbon atom on X that is different from the free radical. Examples of substituents include chloro, bromo, methyl, ethyl, i-propyl, hydroxyl, methoxy, ethoxy, phenoxy, methylthio, phenylthio, cyano, nitro, amino, phthalimide, carboxyl, carbamoyl, N-ethylcarbamoyl, phenyl, and naphthyl groups. The substituents of X are preferably hydroxyl, cyano, nitro, amino, phthalimide, carbamoyl, N-ethylcarbamoyl, and phenyl groups, with hydroxyl, phenoxy, cyano, nitro, phthalimide, and phenyl groups being the most preferred.

[0126] In general formula (4), Y represents an alkylene group having 2 to 6 carbon atoms, such as an ethylene group, propylene group, butylene group, neopentylene group, 1,5-pentylene group, 3-methyl-1,5-pentylene group, 1,6-hexylene group, methylpentylene group, and dimethylbutylene group. Among these, propylene and ethylene groups are preferred, with ethylene being the most preferred.

[0127] In general formula (3), at least one of R1, R2, and R3 is a group represented by general formula (4). In particular, it is preferable that all of R1, R2, and R3 are groups represented by general formula (4).

[0128] Furthermore, the compound may be a mixture of two or more compounds in which one of R1, R2, or R3 is a group represented by general formula (4), two of R1, R2, or R3 are groups represented by general formula (4), or all of R1, R2, and R3 are groups represented by general formula (4).

[0129] Polyester polyols having an isocyanuric ring, represented by general formula (3), can be synthesized by reacting a triol having an isocyanuric ring with an aromatic polycarboxylic acid or its anhydride in which the carboxylic acid is substituted in the ortho position, and a polyhydric alcohol component as essential components.

[0130] Examples of triols having an isocyanuric ring include alkylene oxide adducts of isocyanuric acids such as 1,3,5-tris(2-hydroxyethyl)isocyanuric acid and 1,3,5-tris(2-hydroxypropyl)isocyanuric acid.

[0131] Furthermore, examples of aromatic polycarboxylic acids or their anhydrides in which the carboxylic acid is substituted at the ortho position include orthophthalic acid or its anhydride, naphthalene 2,3-dicarboxylic acid or its anhydride, naphthalene 1,2-dicarboxylic acid or its anhydride, anthraquinone 2,3-dicarboxylic acid or its anhydride, and 2,3-anthracenecarboxylic acid or its anhydride. These compounds may have substituents on any carbon atom of the aromatic ring.

[0132] Examples of substituents include chloro group, bromo group, methyl group, ethyl group, i-propyl group, hydroxyl group, methoxy group, ethoxy group, phenoxy group, methylthio group, phenylthio group, cyano group, nitro group, amino group, phthalimide group, carboxyl group, carbamoyl group, N-ethylcarbamoyl group, phenyl group, and naphthyl group.

[0133] Furthermore, examples of polyhydric alcohol components include alkylenediols having 2 to 6 carbon atoms. Examples include ethylene glycol, propylene glycol, butylene glycol, neopentyl glycol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, methylpentanediol, and dimethylbutanediol. In particular, polyester polyol compounds having an isocyanuric ring are preferred when 1,3,5-tris(2-hydroxyethyl)isocyanuric acid or 1,3,5-tris(2-hydroxypropyl)isocyanuric acid is used as the triol compound having an isocyanuric ring, an aromatic polycarboxylic acid in which the carboxylic acid is substituted at the ortho position or orthophthalic anhydride is used as the anhydride, and ethylene glycol is used as the polyhydric alcohol, as these compounds exhibit particularly excellent oxygen barrier properties and adhesion.

[0134] The isocyanuric ring is highly polar and trifunctional, which can increase the overall polarity of the system and increase the crosslinking density. From this viewpoint, it is preferable to contain 5% by mass or more of the isocyanuric ring relative to the total solid content of the adhesive resin.

[0135] Isocyanate compounds have two or more isocyanate groups in their molecule. Furthermore, the isocyanate compound may be aromatic or aliphatic, and may be a low-molecular-weight compound or a high-molecular-weight compound. Furthermore, the isocyanate compound may be a blocked isocyanate compound obtained by an addition reaction using a known isocyanate blocking agent by a known and conventional method. In particular, polyisocyanate compounds having three or more isocyanate groups are preferred from the viewpoint of adhesion and retort resistance, and aromatic compounds are preferred from the viewpoint of oxygen barrier properties and water vapor barrier properties.

[0136] Specific examples of isocyanate compounds include, for example, tetramethylene diisocyanate, hexamethylene diisocyanate, toluene diisocyanate, diphenylmethane diisocyanate, hydrogenated diphenylmethane diisocyanate, metaxylylene diisocyanate, hydrogenated xylylene diisocyanate, isophorone diisocyanate, and trimers of these isocyanate compounds, as well as adducts, burettes, and allophanates obtained by reacting these isocyanate compounds with low molecular weight active hydrogen compounds or their alkylene oxide adducts, or high molecular weight active hydrogen compounds. Examples of low molecular weight active hydrogen compounds include ethylene glycol, propylene glycol, metaxylylene alcohol, 1,3-bishydroxyethylbenzene, 1,4-bishydroxyethylbenzene, trimethylolpropane, glycerol, pentaerythritol, erythritol, sorbitol, ethylenediamine, monoethanolamine, diethanolamine, triethanolamine, and metaxylylenediamine. Examples of molecular weight active hydrogen compounds include high molecular weight active hydrogen compounds of various polyester resins, polyether polyols, and polyamides.

[0137] In one embodiment, the resin composition includes a phosphate-modified compound, for example, a compound represented by the following general formula (5) or (6) can be used. [ka] In general formula (5), R1, R2, and R3 are groups selected from a hydrogen atom, an alkyl group having 1 to 30 carbon atoms, a (meth)acryloyl group, an optionally substituted phenyl group, and an alkyl group having 1 to 4 carbon atoms, but at least one of them is a hydrogen atom, and n represents an integer from 1 to 4. [ka] In the formula, R4 and R5 are groups selected from a hydrogen atom, an alkyl group having 1 to 30 carbon atoms, a (meth)acryloyl group, an optionally substituted phenyl group, and an alkyl group having 1 to 4 carbon atoms with a (meth)acryloyloxy group, where n is an integer from 1 to 4, x is an integer from 0 to 30, and y is an integer from 0 to 30, except when both x and y are 0.

[0138] More specifically, examples include phosphoric acid, pyrophosphate, triphosphate, methyl acid phosphate, ethyl acid phosphate, butyl acid phosphate, dibutyl phosphate, 2-ethylhexyl acid phosphate, bis(2-ethylhexyl) phosphate, isododecyl acid phosphate, butoxyethyl acid phosphate, oleyl acid phosphate, tetracosyl acid phosphate, 2-hydroxyethyl methacrylate acid phosphate, and polyoxyethylene alkyl ether phosphate, and one or more of these can be used.

[0139] The content of the phosphate-modified compound in the resin composition is preferably 0.005% by mass or more and 10% by mass or less, and more preferably 0.01% by mass or more and 1% by mass or less. By increasing the content of the phosphate-modified compound to 0.005% by mass or more, the oxygen barrier properties and water vapor barrier properties of the laminate of the present invention can be improved. Furthermore, by limiting the content of the phosphate-modified compound to 10% by mass or less, the adhesion of the adhesive layer can be improved.

[0140] The resin composition containing polyester polyol, isocyanate compound, and phosphate-modified compound may also contain plate-like inorganic compound, which can improve the adhesion of the adhesive layer. Furthermore, it can improve the bending load resistance of the laminate of the present invention. Examples of plate-like inorganic compounds include kaolinite-serpentine clay minerals (haloysite, kaolinite, endelite, dickite, nacrite, antigorite, chrysotile, etc.) and pyrophyllite-talc group minerals (pyrophyllite, talc, kerolite, etc.).

[0141] Examples of coupling agents include silane-based coupling agents, titanium-based coupling agents, and aluminum-based coupling agents represented by the general formula (7) below. These coupling agents may be used individually or in combination of two or more types. [ka]

[0142] Examples of silane coupling agents include vinyltrichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-methacryloxytrimethoxysilane, γ-methacryloxypropylmethyldimethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropylmethyldiethoxysilane, γ-methacryloxypropyltriethoxysilane, N-β( Examples include aminoethyl)γ-aminopropylmethyldimethoxysilane, N-β(aminoethyl)γ-aminopropyltrimethoxysilane, N-β(aminoethyl)γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, γ-chloropropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, 3-isocyanatetopropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, and 3-triethoxysilyl-N-(1,3-dimethylbutylidene).

[0143] Examples of titanium-based coupling agents include isopropyl triisostearoyl titanate, isopropyl tri(N-aminoethyl-aminoethyl) titanate, isopropyl tridodecylbenzenesulfonyl titanate, isopropyl tris(dioctyl pyrophosphate) titanate, tetraoctyl bis(didodecyl phosphite) titanate, tetraoctyl bis(ditridecyl phosphite) titanate, bis(dioctyl pyrophosphate) oxyacetate titanate, bis(dioctyl pyrophosphate) ethylene titanate, isopropyl trioctainol titanate, isopropyl dimethacrylate isostearoyl titanate, isopropyl isostearoyl diacrylic titanate, diisostearoylethylene titanate, isopropyl tri(dioctyl phosphate) titanate, isopropyl tricumylphenyl titanate, and dicumylphenyl oxyacetate titanate.

[0144] Specific examples of aluminum-based coupling agents include, for example, acetalkoxyaluminum diisopropylate, diisopropoxyaluminum ethyl acetacetate, diisopropoxyaluminum monomethacrylate, isopropoxyaluminum alkyl acetacetate mono(dioctyl phosphate), aluminum-2-ethylhexanoate oxide trimer, aluminum stearate oxide trimer, and alkyl acetacetate aluminum oxide trimer.

[0145] The resin composition may contain cyclodextrin and / or its derivatives, thereby improving the adhesion of the adhesive layer. Furthermore, the bending load resistance of the laminate of the present invention can be further improved. Specifically, for example, cyclodextrins such as alkylated cyclodextrins, acetylated cyclodextrins, and hydroxyalkylated cyclodextrins, in which the hydrogen atom of the hydroxyl group of the glucose unit of a cyclodextrin is substituted with another functional group, can be used. Branched cyclic dextrins can also be used. Furthermore, the cyclodextrin skeleton in cyclodextrins and cyclodextrin derivatives may be any of the following: α-cyclodextrin consisting of 6 glucose units, β-cyclodextrin consisting of 7 glucose units, or γ-cyclodextrin consisting of 8 glucose units. These compounds may be used individually or in combination of two or more. Furthermore, these cyclodextrins and / or their derivatives may collectively be referred to as dextrin compounds from now on.

[0146] From the viewpoint of compatibility and dispersibility with resin compositions, it is preferable to use cyclodextrin derivatives as the cyclodextrin compound.

[0147] Examples of alkylated cyclodextrins include methyl-α-cyclodextrin, methyl-β-cyclodextrin, and methyl-γ-cyclodextrin. These compounds may be used individually or in combination of two or more.

[0148] Examples of acetylated cyclodextrins include monoacetyl-α-cyclodextrin, monoacetyl-β-cyclodextrin, and monoacetyl-γ-cyclodextrin. These compounds may be used individually or in combination of two or more.

[0149] Examples of hydroxyalkylated cyclodextrins include hydroxypropyl-α-cyclodextrin, hydroxypropyl-β-cyclodextrin, and hydroxypropyl-γ-cyclodextrin. These compounds may be used individually or in combination of two or more.

[0150] Within the limits that do not impair the properties of the present invention, the adhesive layer may contain additives such as pigments such as titanium dioxide, zinc oxide, and carbon black, dyes such as disperse dyes, acid dyes, and cationic dyes, antioxidants, lubricants, colorants, stabilizers, wetting agents, thickeners, coagulants, gelling agents, anti-settling agents, softeners, curing agents, plasticizers, leveling agents, ultraviolet absorbers, and flame retardants.

[0151] The thickness of the adhesive layer is not particularly limited and can be, for example, 1 μm or more and 5 μm or less.

[0152] (Tube container body) The tube container body of the present invention is characterized by comprising the above-mentioned laminate. The tube container body of the present invention will be described below with reference to the drawings. Figure 2 is a simplified diagram showing the configuration of the tube container 20, and Figure 3 is a cross-sectional view AA of Figure 2. As shown in Figure 2, the tube container body 21 comprises a head portion 22 and a body portion 23, and the body portion 23 is characterized in that it is made of the laminated material described above.

[0153] (head) The head portion 22 includes a shoulder portion 24 connected to one end of the torso portion 23 and an extraction port portion 25 connected to the shoulder portion 24. In one embodiment, the spout portion 25 is provided with threads 27 for screwing on the cap 26.

[0154] In one embodiment, the head is made of a resin composition containing polyethylene, thereby improving the recyclability of the tube container. High-density polyethylene, medium-density polyethylene, low-density polyethylene, linear low-density polyethylene, and ultra-low-density polyethylene can be used as the polyethylene. Among these, high-density polyethylene is preferred from the standpoint of shape retention.

[0155] The resin composition may include polyethylene derived from biomass or polyethylene recycled through canine recycling.

[0156] The resin composition may contain the above-mentioned additives, to the extent that it does not impair the specification of the present invention.

[0157] The method for manufacturing the head is not particularly limited and 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.

[0158] When manufacturing a tube container using the 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. The head is formed by compression molding and joined to one opening of the body, thereby manufacturing a tube container consisting of a head and a body. Furthermore, when manufacturing a tube container using injection molding, a tube container consisting of a head and a body can be manufactured by attaching the body to a male mold having a protrusion at the top, placing the male and female molds opposite each other, supplying molten resin composition from the gate, and injection molding to form the head and joining it to one of the openings in the body.

[0159] (torso) In the tube container body 21 of the present invention, the torso portion 23 is connected to the shoulder portion 24 of the head portion 22. The body portion 23 is formed by rolling the laminated material into a cylindrical shape, overlapping its surface resin layer and heat sealing the overlapped portion, thereby providing a welded portion 28. Furthermore, the body portion 23 includes a bottom seal portion 29 formed by heat-sealing the opening of the rolled laminate.

[0160] Heat sealing can be performed using conventionally known methods such as bar sealing, rotary roll sealing, belt sealing, impulse sealing, high-frequency sealing, ultrasonic sealing, and flame sealing.

[0161] (Tube container) The tube container of the present invention comprises the tube container body and a cap. In one embodiment, the tube container 20 is equipped with a cap 26 that is attached to the head 22.

[0162] (cap) The cap is detachably attached to the dispensing opening at the top of the dispenser and serves to close the dispensing opening. The cap is made of a resin composition containing a thermoplastic resin. Examples of thermoplastic resins include polyethylene, polyolefins such as polypropylene, polyester, cellulose resin, and vinyl resin, but polyethylene is particularly preferred from the viewpoint of recyclability. As for polyethylene, high-density polyethylene, medium-density polyethylene, low-density polyethylene, linear low-density polyethylene, and ultra-low-density polyethylene can be used. Among these, high-density polyethylene is preferred from the standpoint of shape retention and ease of opening. Additionally, biomass-derived polyethylene and mechanically recycled polyethylene can be used. Furthermore, the resin composition may also contain the above-mentioned additives, to the extent that it does not impair the properties of the present invention.

[0163] As shown in Figure 2, 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 27. [Examples]

[0164] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to the following examples.

[0165] Example 1 (Fabrication of laminates) Linear low-density polyethylene 1 (ExxonMobil, Exceed2018HA, density 0.918 g / cm³) 3) and high-density polyethylene (ExxonMobil, HTA108, density 0.961 g / cm³) 3 ) and linear low-density polyethylene 2 (Dow Chemical, Dowlex 2098G, density 0.926 g / cm³) 3 The materials were co-extruded using the inflation method to obtain a base film. The base film obtained as described above had a three-layer structure with a total thickness of 40 μm, comprising a layer made of linear low-density polyethylene 1 with a thickness of 10 μm, a layer made of high-density polyethylene with a thickness of 20 μm, and a layer made of linear low-density polyethylene 2 with a thickness of 10 μm (linear low-density polyethylene layer / high-density polyethylene layer / linear low-density polyethylene layer). A 20 nm thick aluminum vapor-deposited film was formed on the surface of a layer of linear low-density polyethylene 1 of the base film by PVD (Physical Vapor Deposition) to obtain the base material.

[0166] A urethane-based adhesive (manufactured by Rock Paint, RU004 / H1) was applied to the vapor-deposited surface of the substrate and dried to form a 3 μm thick adhesive layer. A 100 μm thick unstretched linear low-density polyethylene film (manufactured by Tamapoly, product name: UB-3) was then laminated as a surface resin layer through this adhesive layer.

[0167] Linear low-density polyethylene (Dow Chemical, Dowlex 2045G, density 0.920 g / cm³) 3 ) and adhesive resin (Mitsui Chemicals, Admer NF557), ethylene-vinyl alcohol copolymer (Kuraray, EVAL H171B, density 1.17 g / cm3, ethylene content 38 mol%), adhesive resin (Mitsui Chemicals, Admer NF557), linear low-density polyethylene (Dow Chemical, Dowlex 2045G, density 0.920 g / cm³) 3 ) and were co-extruded into a five-layer film by inflation to obtain a gas barrier layer. The gas barrier layer obtained as described above had a five-layer structure with a total thickness of 60 μm, comprising a layer made of linear low-density polyethylene with a thickness of 17.5 μm, a layer made of adhesive resin with a thickness of 5 μm, a layer made of ethylene-vinyl alcohol copolymer with a thickness of 15 μm, a layer made of adhesive resin with a thickness of 5 μm, and a layer made of linear low-density polyethylene with a thickness of 17.5 μm (linear low-density polyethylene layer / adhesive resin layer / ethylene-vinyl alcohol copolymer layer / adhesive resin layer / linear low-density polyethylene layer).

[0168] On the non-deposited film of the substrate, low-density polyethylene (Novatec LC600A, manufactured by Nippon Polyethylene, density 0.918 g / cm³) is applied. 3 The material was melt-extruded to form a 20 μm thick melt-extruded polyethylene layer, and a layer made of linear low-density polyethylene, which is one of the components of the gas barrier layer, was laminated through this melt-extruded polyethylene layer.

[0169] On the other layer of linear low-density polyethylene that the gas barrier layer comprises, low-density polyethylene (Novatec LC600A, manufactured by Nippon Polyethylene, density 0.918 g / cm³) is placed. 3 A 20 μm thick melt-extruded polyethylene layer was formed by melt-extruding ) and, through this melt-extruded polyethylene layer, a 100 μm thick unstretched linear low-density polyethylene film (manufactured by Tamapoly Co., Ltd., product name: UB-3) was laminated as a heat-seal layer to produce the laminate of the present invention. The polyethylene content in this laminate was 92%.

[0170] Example 2 Linear low-density polyethylene (Dow Chemical, Dowlex 2045G, density 0.920 g / cm³) 3 ) and a compatibilizer (Dow Chemical, maleic anhydride-modified polyethylene, Retain 3000, density 0.870 g / cm³) 3 A blend resin was prepared by blending linear low-density polyethylene and compatibilizer in a ratio of 93% by mass and 7% by mass.

[0171] The blended resin prepared above, along with an adhesive resin (Mitsui Chemicals, Admer NF557), an ethylene-vinyl alcohol copolymer (Kuraray, EVAL H171B, density 1.17 g / cm3, ethylene content 38 mol%), an adhesive resin (Mitsui Chemicals, Admer NF557), and the blended resin were co-extruded in five layers by the inflation method to obtain a gas barrier layer. The gas barrier layer obtained as described above had a five-layer structure with a total thickness of 60 μm, comprising a layer made of a blended resin with a thickness of 17.5 μm, a layer made of an adhesive resin with a thickness of 5 μm, a layer made of an ethylene-vinyl alcohol copolymer with a thickness of 15 μm, a layer made of an adhesive resin with a thickness of 5 μm, and a layer made of a blended resin with a thickness of 17.5 μm (blended resin layer / adhesive resin layer / ethylene-vinyl alcohol copolymer layer / adhesive resin layer / blended resin layer).

[0172] The laminate of the present invention was fabricated in the same manner as in Example 1, except that the gas barrier layer was changed to one fabricated as described above. The polyethylene content in this laminate was 91%.

[0173] Comparative Example 1 A laminate was prepared in the same manner as in Example 1, except that the base film was a 12 μm thick biaxially oriented polyethylene terephthalate (Toyobo, Ester Film E5100). The polyethylene content in this laminate was 87%.

[0174] (Preparation of tube containers) The laminate obtained as described above was processed into a 120 mm wide slit using a bobbin cutter. The ends in the width direction were overlapped so that the overlap width was approximately 1.5 mm, and then the overlapped ends were heat-sealed to obtain a cylindrical raw material. The obtained raw material was cut to a length of 122 mm to create a cylindrical body that would become the body of the tube container.

[0175] The cylindrical body is mounted on a mandrel for forming tube containers, and a head consisting of a frustoconical shoulder and a continuous cylindrical extraction port is attached to one end of the cylindrical body, made of high-density polyethylene (Novatec HJ360, manufactured by Nippon Polyethylene, density 0.951 g / cm³). 3 A tube container was fabricated by injection molding, as shown in Figure 3. The spout at the top of the resulting tube container had an outer diameter of 13 mm and a height of 1.5 mm, and a spiral groove was provided on the side of the spout. The outer diameter of the shoulder portion was 38 mm.

[0176] Next, the high-density polyethylene was injected into a mold for cap molding and molded to produce a cap, thereby obtaining the tube container of the present invention.

[0177] <<Recyclability Assessment>> The recyclability of the laminates for packaging materials obtained in the above examples and comparative examples was evaluated based on the following evaluation criteria. The evaluation results are summarized in Table 1. (Evaluation Criteria) ○: The content of the same polyolefin in the laminate for packaging materials was 90% by mass or more. ×: The content of the same polyolefin in the laminate for packaging materials was less than 90% by mass.

[0178] <<Shoulder adhesive strength>> A test specimen was obtained by cutting a 15mm wide strip from the joint between the torso and shoulder towards the hem. This test specimen was pulled at a test speed of 300 mm / min using a tensile testing machine (Orientec Co., Ltd., RTC-1310A), and the peel strength at which the torso separated from the shoulder was measured. The measurement results are summarized in Table 1.

[0179] <<Side seam strength>> A 15mm wide strip was cut perpendicular to the side seam (overlapping area) of the torso, and the strength at which it broke was measured by pulling it on a tensile testing machine at a test speed of 300mm / min. The measurement results are summarized in Table 1.

[0180] <<Leakage Assessment>> A cap was screwed onto the dispensing port of the tube container, then 120g of commercially available toothpaste was filled into the opening of the cylindrical body, and the opening of the cylindrical body was heat-sealed. The set tightening torque for closing the cap was 4.7 kg·cm. The container was left at room temperature for two weeks, and the contents were visually inspected daily for leakage. The criteria for evaluating leak resistance were as follows. (Evaluation Criteria) ○: No leakage of contents was observed even after two weeks. ×: Leakage of contents was observed before 2 weeks had elapsed.

[0181] [Table 1] [Explanation of symbols]

[0182] 10: Laminate, 11: Surface resin layer, 12: Substrate, 13: Gas barrier layer, 13A: First polyethylene resin layer, 13B: First adhesive layer, 13C: Layer containing gas barrier resin, 13D: Second adhesive layer, 13E: Second polyethylene resin layer, 14: Heat seal layer, 15: Vapor-deposited film, 20: Tube container, 21: Tube container body, 22: Head, 23: Body, 24: Shoulder, 25: Dispensing port, 26: Cap, 27: Thread, 28: Welded part, 29: Bottom seal part

Claims

1. A film comprising at least a surface resin layer, a substrate, and a heat seal layer in this order, the surface resin layer, the base material, and the heat seal layer are made of the same material, the substrate has a vapor-deposited film on at least one surface, the surface resin layer has heat-sealability, the same material is polyethylene; A laminate, characterized in that the polyethylene content in the entire laminate is 90 mass % or more.

2. A laminate as described in claim 1, comprising a gas barrier layer between the substrate and the heat seal layer.

3. 3. The laminate according to claim 2, further comprising a melt-extruded polyethylene layer or an adhesive layer at least one of between the surface resin layer and the substrate, between the substrate and the gas barrier layer, and between the gas barrier layer and the heat seal layer.

4. 4. The laminate according to claim 1, wherein the polyethylene constituting the surface resin layer and the heat seal layer is low-density polyethylene and / or linear low-density polyethylene.

5. The laminate according to any one of claims 1 to 4, wherein the vapor-deposited film is a metal vapor-deposited film.

6. The laminate according to any one of claims 2 to 5, wherein the gas barrier layer comprises a first polyethylene resin layer, a first adhesive layer, a layer containing a gas barrier resin, a second adhesive layer, and a second polyethylene resin layer.

7. The laminate according to claim 6 , wherein the layer containing the gas barrier resin has a thickness of 20 μm or more and 100 μm or less.

8. The laminate according to any one of claims 1 to 7, wherein the surface resin layer and the heat seal layer have a thickness of 30 µm or more and 150 µm or less.

9. The laminate according to any one of claims 1 to 8, wherein the substrate has a thickness of 10 µm or more and 50 µm or less.

10. The laminate according to any one of claims 1 to 9, wherein the thickness of the vapor-deposited film is 1 nm or more and 150 nm or less.

11. The laminate according to any one of claims 1 to 10, which is used for a tube container.

12. It has a head and a body, The head portion has a shoulder portion connected to one end of the body portion and a sampling port portion connected to the shoulder portion, A tube container, characterized in that the body portion is formed from the laminate according to any one of claims 1 to 11.

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

14. The tube container according to claim 12 or 13, further comprising a cap made of a resin composition containing polyethylene.

Images