Substrate for forming vapor-deposited film, vapor-deposited substrate, laminate and packaging container

Abstract

To provide a substrate for forming a vapor-deposited film favorably usable for producing a mono-material packaging container, with high adhesion to a vapor-deposited film, and capable of effectively preventing delamination when made into a packaging container.SOLUTION: A substrate for forming a vapor-deposited film at least includes a first polyethylene resin layer with a vapor-deposited film formed on a surface thereof. A density of a polyethylene resin composing the first polyethylene resin layer is 0.943 g / cm3 or less. A drawing process is applied to the substrate for forming a vapor-deposited film.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a substrate for forming a vapor-deposited film, a vapor-deposition substrate, a laminate, and a packaging container.

[0002] Conventionally, resin films made of polyester resins such as polyethylene terephthalate (hereinafter also referred to as polyester films) have been used as substrates constituting laminates used in the manufacture of packaging containers because they are excellent in mechanical properties, chemical stability, heat resistance and transparency, and are inexpensive.

[0003] Such polyester films are usually laminated with a polyethylene film, which is a sealant layer, to form a laminate, which is then formed into a packaging container.

[0004] The packaging containers made from the above-mentioned laminate of different resin films, i.e., a polyester film and a polyethylene film, are difficult to separate into their respective layers, and packaging containers collected after use are not suitable for recycling, and therefore are not actively recycled.

[0005] In order to improve the recyclability of packaging containers, studies are being conducted on the use of stretched polyethylene film (stretched polyethylene film) as the base material instead of polyester film, and the production of packaging containers using laminates made of the same material (mono-material packaging containers). Summary of the Invention [Problem to be solved by the invention]

[0006] Recently, the inventors attempted to form a vapor-deposited film on the surface of a stretched polyethylene film in order to compensate for the reduced gas barrier properties, design, and gloss that result from changing from polyester film to a stretched polyethylene film. However, they discovered a new problem in that the adhesion between the stretched polyethylene film and the vapor-deposited film was insufficient, and when a packaging container was produced using the stretched polyethylene film with the vapor-deposited film formed thereon, there was a risk of delamination occurring between the stretched polyethylene film and the vapor-deposited film.

[0007] And, surprisingly, the inventors have found that by adjusting the density of the polyethylene resin in the layer forming the vapor-deposited film of the substrate made of polyethylene resin, it is possible to significantly improve the adhesion between the layer and the vapor-deposited film, thereby solving the above-mentioned problems.

[0008] The present invention has been made based on such findings, and the problem to be solved by the present invention is to provide a substrate for forming a vapor-deposited film, which can be suitably used for producing mono-material packaging containers, has high adhesion to a vapor-deposited film, and can effectively prevent delamination when used as a packaging container.

[0009] Another problem to be solved by the present invention is to provide a laminate including the above-mentioned substrate for forming a vapor-deposited film, and a laminate and a packaging container. [Means for solving the problem]

[0010] The substrate for forming a deposited film of the present invention includes at least a first polyethylene resin layer on a surface of which a deposited film is formed, The density of the polyethylene resin constituting the first polyethylene resin layer is 0.943 g / cm 3 is as follows: The substrate for forming a deposited film is characterized in that it has been subjected to a stretching treatment.

[0011] In one embodiment, the substrate for deposition film formation has a multilayer structure, and each layer constituting the substrate for deposition film formation having the multilayer structure is made of a polyolefin resin.

[0012] In one embodiment, the polyethylene resins constituting adjacent layers have different densities, providing a density gradient.

[0013] In one embodiment, the density difference of the polyethylene resin between adjacent layers is 0.05 g / cm 3 The following is the result.

[0014] The deposition substrate of the present invention includes at least a substrate and a deposition film, The substrate is the substrate for forming a deposited film, The vapor-deposited film is provided on a first polyethylene resin layer of a substrate for forming a vapor-deposited film, The first sealant layer is characterized by being made of a polyethylene resin.

[0015] The laminate of the present invention includes at least a substrate, a vapor-deposited film, and a first sealant layer, The substrate is the substrate for forming a deposited film, The deposited film is characterized in that it is provided on a first polyethylene resin layer of a substrate for forming a deposited film.

[0016] In one embodiment, the substrate further includes a second sealant layer on a surface opposite to the surface on which the first sealant layer is provided, and the second sealant layer is made of a polyethylene resin.

[0017] In one embodiment, the laminate of the present invention further comprises a barrier coat layer between the first sealant layer and the vapor-deposited film.

[0018] In one embodiment, the laminate of the present invention is used in a packaging container.

[0019] In one embodiment, the content of the polyethylene resin in the entire laminate is 80 mass % or more.

[0020] The packaging container of the present invention is characterized by comprising the above laminate.

[0021] In one embodiment, the packaging container is a laminate tube. Effect of the Invention

[0022] According to the present invention, it is possible to provide a substrate that can be suitably used for producing a mono-material packaging container, can significantly improve the interlayer adhesion with a vapor-deposited film, and can achieve favorable gas barrier properties. According to the present invention, there is also provided a deposition substrate comprising the above-mentioned substrate and a deposition film. Furthermore, according to the present invention, it is possible to provide a packaging container comprising a laminate including the above-mentioned substrate, a vapor-deposited film, and a sealant layer. [Brief description of the drawings]

[0023] [Figure 1] FIG. 1 is a schematic cross-sectional view showing one embodiment of a substrate 10 for forming a deposited film of the present invention. [Diagram 2] FIG. 1 is a schematic cross-sectional view showing one embodiment of a deposition substrate 20 of the present invention. [Diagram 3] FIG. 1 is a schematic structural diagram illustrating an embodiment of a deposition apparatus. [Figure 4] FIG. 1 is a schematic cross-sectional view showing one embodiment of a laminate 30 of the present invention. [Diagram 5] FIG. 1 is a schematic cross-sectional view showing one embodiment of a laminate 30 of the present invention. [Figure 6] FIG. 1 is a front view showing a laminate tube 40 which is one embodiment of a packaging container of the present invention. [Figure 7] FIG. 7 is a cross-sectional view taken along line aa of FIG. [Figure 8] 1 is a front view showing a packaging bag 50 which is one embodiment of the packaging container of the present invention. [Figure 9] FIG. 1 is a perspective view showing a stand-up pouch 60 which is one embodiment of the packaging container of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] (Substrate for vapor deposited film formation) The substrate for forming a deposited film of the present invention has a polyethylene resin layer, similar to the first and second sealant layers made of a polyethylene resin described below. Since the substrate and the sealant layer are made of the same resin material, the laminate can be used as a material with excellent recyclability for mono-material packaging containers and the like. The substrate may be a single layer or a multilayer as long as it has a polyethylene resin layer. In the case of a multilayer substrate, the substrate can be produced by a coextrusion method in which each polyolefin resin such as a polyethylene resin is heated and melted in a separate extruder, laminated in a molten state by a method such as a coextrusion multilayer die method or a feed block method, and then molded into a film by an inflation method, a T-die method, or the like.

[0025] For example, when the substrate has a multilayer structure formed by coextrusion, it may have, in order from the first polyethylene resin layer on the side in contact with the vapor-deposited film, second, third, fourth, etc. polyethylene resin layers (hereinafter sometimes referred to as "other polyethylene resin layers") The provision of the other polyethylene resin layers can improve the performance of the laminate, such as heat resistance, strength, transparency, and stretchability.

[0026] In the present invention, the substrate is characterized in that it has been subjected to a stretching treatment, which can improve the strength and heat resistance of the substrate, as well as the printability. The stretching process may be uniaxial stretching or biaxial stretching.

[0027] The stretching ratio of the substrate in the machine direction (MD direction) and the transverse direction (TD direction) is preferably 2 times or more and 15 times or less, and more preferably 3 times or more and 10 times or less. By setting the stretching ratio at 2 times or more, the strength and heat resistance of the substrate can be further improved. In addition, the printability of the substrate can be improved. From the viewpoint of the breaking limit of the substrate, the stretching ratio is preferably 15 times or less.

[0028] In the present invention, the substrate 10 for forming a deposited film has a density of 0.943 g / cm as a layer on which the deposited film is formed. 3 The film includes at least a first polyethylene resin layer 11 made of the following polyethylene resin.

[0029] The density of the first polyethylene resin layer is 0.943 g / cm 3 The following polyethylene resin may be a biomass-derived polyethylene resin or a polyethylene resin recycled by mechanical recycling or chemical recycling.

[0030] Density of the first polyethylene resin layer: 0.943 g / cm 3 The content of the following polyethylene resin is preferably 50% by mass or more, more preferably 70% by mass or more, further preferably 80% by mass or more, and particularly preferably 90% by mass or more. Density of the first polyethylene resin layer: 0.943 g / cm 3 By making the content of the following polyethylene resin 50% by mass or more, the adhesion to the vapor-deposited film can be further significantly improved.

[0031] Density of the first polyethylene resin layer: 0.943 g / cm 3 The melting point of the following polyethylene resin is preferably 60° C. or higher and 135° C. or lower, and more preferably 65° C. or higher and 130° C. or lower. By making the melting point 60° C. or higher, the printability, strength, and heat resistance of the substrate can be further improved. By making the melting point 135° C. or lower, the difference in appropriate stretching temperature between each layer can be reduced.

[0032] Density of the first polyethylene resin layer: 0.943 g / cm 3The MFR of the following polyethylene resin is preferably 0.1 g / 10 min to 5 g / 10 min, more preferably 0.2 g / 10 min to 4 g / 10 min. By setting the MFR to 0.1 g / 10 min to 5 g / 10 min, the film formability in the inflation method is stabilized.

[0033] The first polyethylene resin layer has a density of 0.943 g / cm within a range that does not impair the characteristics of the present invention. 3 The first polyethylene resin layer may contain the following resin materials (other resin materials) other than polyethylene resin: From the viewpoint of adhesion to the vapor-deposited film, it is preferable that the first polyethylene resin layer does not contain other resin materials. In addition, the first polyethylene resin layer may contain additives within the range that does not impair the characteristics of the present invention, such as crosslinking agents, antioxidants, antiblocking agents, slip agents, UV absorbers, light stabilizers, fillers, reinforcing agents, antistatic agents, pigments, and modifying resins.

[0034] The other polyethylene resin layers are made of polyethylene resin. As the polyethylene resin, high density polyethylene resin (HDPE), medium density polyethylene resin (MDPE), low density polyethylene resin (LDPE), linear low density polyethylene resin (LLDPE) and very low density polyethylene resin (VLDPE) can be used. Moreover, as the polyethylene resin, a copolymer of ethylene and another monomer can also be used. Furthermore, as the polyethylene resin, a biomass-derived polyethylene resin or a mechanically recycled or chemically recycled polyethylene resin can also be used.

[0035] In a substrate having a multilayer structure, the densities of the polyethylene resins constituting adjacent layers may be the same or different, i.e., the polyethylene resin layers constituting the substrate may have a density gradient. In a polyethylene resin layer having a density gradient, if the density difference between the layers is large, delamination may occur at the interface. Therefore, the density difference between the layers is set to 0.05 g / cm 3 It is preferable that the concentration is 0.04 g / cm or less. 3 It is even more preferable that:

[0036] (a) In one embodiment, the substrate having a multilayer structure has a five-layer structure including a first polyolefin resin layer, a second polyethylene resin layer composed of a medium-density polyethylene resin, a third polyethylene resin layer composed of a linear low-density polyethylene resin, a fourth polyethylene resin layer composed of a medium-density polyethylene resin, and a fifth polyolefin resin layer composed of a high-density polyethylene resin. (b) In one embodiment, the substrate having a multilayer structure has a seven-layer structure including a first polyethylene resin layer, a second resin layer composed of a blend resin of high-density polyethylene resin and medium-density polyethylene resin, a third polyethylene resin layer composed of medium-density polyethylene resin, a fourth polyethylene resin layer composed of a linear low-density polyethylene resin, a fifth polyethylene resin layer composed of medium-density polyethylene resin, a sixth resin layer composed of a blend resin of high-density polyethylene resin and medium-density polyethylene resin, and a seventh polyolefin resin layer composed of high-density polyethylene resin. (c) In one embodiment, the substrate having a multilayer structure has a three-layer structure including a first polyethylene resin layer, a second polyethylene resin layer composed of a linear low-density polyethylene resin, and a third polyolefin resin layer composed of a medium-density polyethylene resin. (d) In one embodiment, the substrate having a multilayer structure has a two-layer structure of a first polyethylene resin layer and a second polyolefin resin layer made of a medium-density polyethylene resin. (e) In one embodiment, the substrate having a multilayer structure has a five-layer structure including a first polyethylene resin layer containing an olefin-based elastomer resin, a second polyolefin resin layer composed of a medium-density polyethylene resin, a third polyolefin resin layer composed of a linear low-density polyethylene resin, a fourth polyolefin resin layer composed of a medium-density polyethylene resin, and a fifth polyolefin resin layer composed of an olefin-based elastomer resin and a medium-density polyethylene resin.

[0037] As an embodiment of the multilayered substrate by the co-extrusion method as described above, for example, each resin is heated and melted by an extruder, and a five-layer laminate consisting of the first to fifth polyethylene resin layers is formed by a feed block method, and then the laminate is formed into a tube by an inflation method, and the insides of the tube are pressed together by a rubber roll or the like to form a ten-layered multilayered film. The multilayered film thus obtained has a layer structure that is symmetrical from top to bottom in the cross-sectional thickness direction. That is, for example, when five layers consisting of the first to fifth polyethylene resin layers are laminated by a co-extruder, the obtained laminated film becomes a substrate having a ten-layered structure consisting of the first / second / third / fourth / fifth / fifth / fourth / third / second / first polyethylene resin layers in order from the surface. However, in reality, the two adjacent fifth polyethylene resin layers in the thickness cross-sectional direction can be regarded as one layer, so that the substrate can have a nine-layered multilayer structure consisting of the first / second / third / fourth / fifth / fourth / third / second / first polyethylene resin layers. The multilayer film obtained by such a manufacturing method is sometimes called a “block film.” According to the above-mentioned manufacturing method, the number of defective products in the manufacturing process can be significantly reduced, and ultimately, the production efficiency can be improved.

[0038] The substrate may have a printed layer on its surface. The image formed on the printed layer is not particularly limited, and may be a character, a pattern, a symbol, or a combination thereof. The printing layer on the substrate can be formed using ink derived from biomass, which reduces the environmental impact. The method for forming the printed layer is not particularly limited, and examples of the method include conventionally known printing methods such as gravure printing, offset printing, and flexographic printing.

[0039] The substrate may be subjected to a surface treatment, which can improve adhesion to adjacent layers. The method of surface treatment is not particularly limited, and examples thereof include physical treatments such as corona discharge treatment, ozone treatment, low-temperature plasma treatment using oxygen gas and / or nitrogen gas, and glow discharge treatment, as well as chemical treatments such as oxidation treatment using chemicals.

[0040] The thickness of the substrate, whether it is a single-layer structure or a multi-layer structure, is preferably 1 μm or more and 60 μm or less, more preferably 9 μm or more and 60 μm or less, and even more preferably 12 μm or more and 50 μm or less. By making the thickness of the substrate 1 μm or more, the heat resistance and strength of the substrate can be improved. By making the thickness of the substrate 60 μm or less, the processability of the substrate can be improved.

[0041] (vapor deposition base material) As shown in FIG. 2, the deposition substrate 20 of the present invention comprises the above-mentioned substrate 10 for forming a deposited film and a deposited film 21, and is characterized in that the deposited film 21 is provided on a first polyethylene resin layer 11.

[0042] Hereinafter, each layer of the deposition base material will be described. Note that the substrate 10 for forming a deposited film has been described above, so a description thereof will be omitted here.

[0043] (evaporated film) The deposition base material has a deposition film on the first polyethylene resin layer, which can improve the gas barrier properties of the deposition base material, specifically, the oxygen barrier properties and water vapor barrier properties.

[0044] The vapor deposition film 21 may be composed of a metal or an inorganic oxide, but a vapor deposition film composed of a metal (hereinafter referred to as a metal vapor deposition film) is preferred because it can impart a glossy appearance to a container produced using the vapor deposition base material of the present invention and improve its design. Examples of metals that can be used to form the metal vapor deposition film include aluminum, chromium, tin, nickel, copper, silver, gold, and platinum. Examples of the metal oxide include aluminum oxide, silicon oxide, magnesium oxide, calcium oxide, zirconium oxide, titanium oxide, boron oxide, hafnium oxide, and barium oxide.

[0045] Among the above, aluminum is particularly preferred because it has high gas barrier properties and can impart a good glossy feel.

[0046] The surface of the deposited film is preferably subjected to the above-mentioned surface treatment, which can improve adhesion to adjacent layers.

[0047] The thickness of the evaporated film is preferably 1 nm or more and 150 nm or less, more preferably 5 nm or more and 60 nm or less, and even more preferably 10 nm or more and 40 nm or less. By making the thickness of the vapor-deposited film 1 nm or more, the gas barrier properties and gloss of the vapor-deposited substrate can be further improved. Moreover, by setting the thickness of the vapor-deposited film to 150 nm or less, a vapor-deposited base material that can be suitably used for producing a mono-material packaging container can be obtained. Furthermore, the occurrence of cracks in the vapor-deposited film 21 can be prevented.

[0048] The method for forming the vapor-deposited film may be a conventional method, for example, a physical vapor deposition method (PVD method) such as a vacuum deposition method, a sputtering method, or an ion plating method, or a chemical vapor deposition method (CVD method) such as a plasma chemical vapor deposition method, a thermal chemical vapor deposition method, or a photochemical vapor deposition method. Hereinafter, one embodiment of the method for forming the evaporated film will be described, but the method for forming the evaporated film is not limited thereto.

[0049] Specifically, the deposition film can be formed by using (1) a vacuum deposition method in which a metal or metal oxide is used as a raw material, heated to vaporize it, and then deposited on the first polyethylene resin layer of the substrate, (2) an oxidation reaction deposition method in which a metal or metal oxide is used as a raw material, oxidized by introducing oxygen, and then deposited on the first polyethylene resin layer of the substrate, and (3) a plasma-assisted oxidation reaction deposition method in which the oxidation reaction is assisted by plasma, etc. In the above, the deposition material can be heated by, for example, a resistance heating method, a high-frequency induction heating method, an electron beam heating method (EB), etc.

[0050] A method for forming a vapor-deposited film of an inorganic substance or an inorganic oxide by physical vapor deposition will be described below. Fig. 3 is a schematic diagram showing an example of a take-up type vacuum deposition apparatus. As shown in Fig. 3, in a vacuum chamber B of a take-up type vacuum deposition apparatus A, a substrate X unwound from a winding roll C is guided to a cooled coating drum F via guide rolls D and E. In one embodiment, the device A has a plasma treatment device G disposed between the guide roll E and a cooled coating drum F. The plasma treatment device G irradiates a plasma gas onto the surface of the first polyethylene resin layer of the substrate X, thereby subjecting the surface of the first polyethylene resin layer of the substrate X to plasma treatment before the deposition film is formed. Next, the deposition source I (e.g., aluminum metal or aluminum oxide) heated and evaporated in the crucible H is deposited on the first polyethylene resin layer of the substrate guided onto the cooled coating drum F to form a deposition film. The deposition of the deposition source I may be performed through masks J, J, and further, if necessary, may be performed while blowing oxygen gas or the like from an oxygen gas blowing port K. Next, the substrate X on which the vapor-deposited film has been formed is sent out via guide rolls L and M, and taken up on a take-up roll N, thereby completing the vapor-deposited film formation by this apparatus. The above steps may be repeated to form a multi-layered deposition film made of different materials. The multi-layered deposition film may be formed by using the above apparatus twice, or by using an apparatus in which the above apparatuses are connected. The formation of such a vapor-deposited film is disclosed in, for example, Japanese Patent No. 4569982.

[0051] (Laminate) A laminate 30 of the present invention includes at least a substrate 10 for formation of a deposited film, a deposited film 21, and a first sealant layer 31, as shown in FIG. In one embodiment, the laminate 30 includes a second sealant layer 32 on the surface of the substrate 10 for forming a deposited film opposite to the first sealant layer 31 side, as shown in FIG. The laminate 30 may have a barrier coat layer (not shown) on the vapor-deposited film 21.

[0052] The content of polyethylene in the total amount of solids contained in the laminate is preferably 80% by mass or more, and more preferably 90% by mass or more, which makes it possible to obtain a laminate that can be suitably used for producing mono-material packaging containers.

[0053] Each layer of the laminate will be described below. Note that the substrate for forming a deposited film and the deposited film have been described above, so descriptions thereof will be omitted here.

[0054] (First and second sealant layers) The first and second polyolefin resin layers are made of polyolefins, such as polyethylene resins, polypropylene resins, polymethylpentene, ethylene-propylene copolymers, and propylene-butene copolymers. Of these, polyethylene resins are preferred from the viewpoint of recyclability.

[0055] In one embodiment, the first and second polyolefin resin layers contain a compatibilizer, which can effectively prevent the gas barrier resin and the polyethylene resin from being mixed uniformly and causing a decrease in the physical properties and transparency when the packaging container produced using the laminate of the present invention is heated and melted for recycling.

[0056] The compatibilizer may be appropriately selected from conventionally known ones and used. From the viewpoint of recyclability, however, unsaturated carboxylic acid modified polyolefin resins are preferred, and among them, maleic anhydride modified polyethylene resins are more preferred.

[0057] The content of the compatibilizer in the first and second polyolefin resin layers is preferably 5% by mass or more and 30% by mass or less. By setting the content of the compatibilizer in the first and second polyolefin resin layers to 5% by mass or more, the above-mentioned effects can be further improved. By setting the content of the compatibilizer in the first and second polyolefin resin layers to 30% by mass or less, the strength and heat resistance of the substrate can be improved.

[0058] As long as the characteristics of the present invention are not impaired, the first and second polyethylene resin layers may contain a resin material other than a polyolefin resin, such as (meth)acrylic resin, vinyl resin, cellulose resin, polyamide resin, polyester resin, and ionomer resin. From the viewpoint of recyclability, it is particularly preferable that the first and second polyolefin resin layers contain no resin other than polyethylene resin.

[0059] Furthermore, the first and second polyethylene resin layers may contain the above-mentioned additives, provided that the characteristics of the present invention are not impaired.

[0060] The thickness of the first and second polyolefin resin layers is preferably 5 μm or more and 100 μm or less, more preferably 10 μm or more and 50 μm or less. By making the thickness of the polyolefin resin layer 5 μm or more, the strength and heat resistance of the laminate of the present invention can be improved. By making the thickness of the polyolefin resin layer 100 μm or less, the processability of the laminate of the present invention can be improved.

[0061] The first and second polyolefin resin layers may have the same or different configurations.

[0062] (Barrier coat layer) The deposition substrate of the present invention may further include a barrier coat layer on the deposition film (between the first sealant layer and the deposition film, or between the deposition film and the substrate), thereby improving the gas barrier properties of the deposition substrate.

[0063] In one embodiment, the barrier coat layer is composed of a gas barrier resin such as an ethylene-vinyl alcohol copolymer (EVOH), polyvinyl alcohol, polyacrylonitrile, polyamide resins such as nylon 6, nylon 6,6 and polymetaxylylene adipamide (MXD6), polyester resin, polyurethane resin, and (meth)acrylic resin.

[0064] 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 making the thickness of the barrier coat layer 0.01 μm or more, the gas barrier property can be further improved. By making the thickness of the barrier coat layer 10 μm or less, the processability of the deposition substrate can be improved. In addition, the deposition substrate can be suitably used for producing mono-material packaging containers.

[0065] The barrier coat layer can be formed by dissolving or dispersing the above-mentioned material in water or an appropriate solvent, applying the solution or dispersion, and drying the solution.

[0066] In another embodiment, the barrier coat layer is a gas barrier coating film containing at least one resin composition such as a hydrolysate of a metal alkoxide or a hydrolyzed condensate of a metal alkoxide obtained by polycondensing a mixture of a metal alkoxide and a water-soluble polymer by a sol-gel method in the presence of a sol-gel catalyst, water, an organic solvent, etc. By providing such a barrier coat layer on the vapor-deposited film, the occurrence of cracks in the vapor-deposited film can be effectively prevented.

[0067] In one embodiment, the metal alkoxide is represented by the following general formula: R 1 n M(OR 2 ) m (In the formula, R 1 , R 2 each represents an organic group having 1 to 8 carbon atoms, M represents a metal atom, n represents an integer of 0 or more, m represents an integer of 1 or more, and n+m represents the atomic valence of M.

[0068] As the metal atom M, for example, silicon, zirconium, titanium, aluminum, etc. can be used. Also, R 1 and R 2 Examples of the organic group represented by the formula (I) include alkyl groups such as a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, and an i-butyl group.

[0069] Examples of metal alkoxides that satisfy the above general formula include tetramethoxysilane (Si(OCH 3 ) 4 ), tetraethoxysilane (mass%) Si(OC 2 H 5 ) 4 ), tetrapropoxysilane (Si(OC 3 H 7 ) 4 ), tetrabutoxysilane (Si(OC 4 H 9 ) 4 ) etc.

[0070] It is also preferable to use a silane coupling agent together with the metal alkoxide. As the silane coupling agent, a known organoalkoxysilane containing an organic reactive group can be used.

[0071] As the water-soluble polymer, polyvinyl alcohol and an ethylene-vinyl alcohol copolymer are preferred, and from the viewpoints of oxygen barrier properties, water vapor barrier properties, water resistance and weather resistance, it is preferred to use these in combination.

[0072] The thickness of the gas barrier coating film is preferably from 0.01 μm to 10 μm, and more preferably from 0.1 μm to 5 μm, which can further improve the gas barrier properties. By making the thickness of the gas barrier coating film 0.01 μm or more, the oxygen barrier property and water vapor barrier property of the barrier laminate can be improved, and the occurrence of cracks in the vapor-deposited film can be prevented. By setting the thickness of the gas barrier coating film to 10 μm or less, it is possible to provide a deposition substrate that can be suitably used for producing mono-material packaging containers.

[0073] The gas barrier coating film can be formed by applying a composition containing the above-mentioned materials by a conventionally known means such as roll coating using a gravure roll coater or the like, spray coating, spin coating, dipping, brushing, bar coding, or an applicator, and then polycondensing the composition by a sol-gel method. As the sol-gel catalyst, an acid or an amine compound is preferable.

[0074] The composition may further contain an acid, which is used as a catalyst in the sol-gel process, mainly for the hydrolysis of alkoxides, silane coupling agents, and the like. As the acid, mineral acids such as sulfuric acid, hydrochloric acid, nitric acid, etc., and organic acids such as acetic acid, tartaric acid, etc. can be used.

[0075] The composition may also contain an organic solvent, such as methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, or n-butanol.

[0076] Hereinafter, one embodiment of the method for forming a gas barrier coating film will be described. First, a composition is prepared by mixing a metal alkoxide, a water-soluble polymer, a sol-gel catalyst, water, an organic solvent, and optionally a silane coupling agent, etc. In the composition, a polycondensation reaction gradually proceeds. Next, the composition is applied onto the deposition film by the above-mentioned conventionally known method and dried. This drying causes the polycondensation reaction of the alkoxide and the water-soluble polymer (and the silane coupling agent if the composition contains a silane coupling agent) to proceed further, forming a layer of a composite polymer. Finally, the gas barrier coating film can be formed by heating.

[0077] (packaging container) The packaging container of the present invention is characterized by comprising the above-mentioned laminate.

[0078] Specific examples of the packaging container of the present invention include laminate tubes, packaging bags, and lids.

[0079] (Laminated tube) In one embodiment, the packaging container of the present invention is a laminate tube. Hereinafter, the laminate tube 40 of the present invention will be described with reference to the drawings. Fig. 6 is a diagram showing the configuration of the laminate tube 40 in a simplified manner, and Fig. 7 is a cross-sectional view taken along line aa in Fig. 6. As shown in Fig. 6, the laminate tube 40 is characterized in that it comprises a laminate tube body 41 having a head 42 and a body 43, and the body 43 is formed from the laminate 30.

[0080] (head) The head portion 42 has a shoulder portion 44 connected to one end of the body portion 43 and a sampling port portion 45 connected to the shoulder portion 44. In one embodiment, the spout portion 45 includes a thread 47 for screwing the cap 46 thereon.

[0081] In one embodiment, the head 42 is made of a polyethylene resin, which can improve the recyclability of the laminate tube. The polyethylene resin may be a high-density polyethylene resin, a medium-density polyethylene resin, a low-density polyethylene resin, a linear low-density polyethylene resin, or an ultra-low-density polyethylene resin. Among these, high density polyethylene resin is preferred from the viewpoint of shape retention. Moreover, as the polyethylene resin, a polyethylene resin derived from biomass or a polyethylene resin recycled by mechanical recycling or chemical recycling can be used. The head 42 may contain the above-mentioned additives, as long as the characteristics of the present invention are not impaired.

[0082] The method for producing the head 42 is not particularly limited, and the head 42 can be produced by a conventionally known method. For example, the head 42 can be produced by a compression molding method or an injection molding method, and can be joined to the body portion.

[0083] When the laminated tube 40 is manufactured using the compression molding method, the body 43 is attached to a male mold having a convex portion on the top, the male and female molds are then opposed to each other, and a material such as molten polyethylene resin is supplied into the male and female molds. The head 42 is formed by compression molding and joined to one opening of the body 43, thereby manufacturing the laminated tube 40 consisting of the head 42 and the body 43. Furthermore, when the laminated tube 40 is manufactured using an injection molding method, the body 43 is attached to a male mold having a convex portion on the top, the male mold and female mold are then opposed to each other, and a material such as molten polyethylene resin is supplied from a gate, and the head 42 is formed by injection molding and joined to one opening of the body 43, thereby producing a laminated tube consisting of the head 42 and the body 43.

[0084] (Torso) In the laminate tube body 41 of the present invention, the trunk portion 43 is connected to a shoulder portion 44 of the head portion 42 . The body portion 43 can be obtained by rolling the laminate 30 into a cylindrical shape, overlapping the first sealant layer 31 and the second sealant layer 32, and heat-sealing the polymerized portions to form a welded portion 48. The body 43 also includes a bottom seal 49 formed by heat sealing the opening of the rolled laminate 30 .

[0085] Heat sealing can be performed by a conventional method such as bar sealing, rotary roll sealing, belt sealing, impulse sealing, high frequency sealing, ultrasonic sealing, or flame sealing.

[0086] (cap) The laminate tube 40 may include a cap 46 . The cap is removably attached to the extraction port of the head and serves to close the extraction port. The cap is made of a thermoplastic resin. Examples of the thermoplastic resin include polyolefin resins such as polyethylene and polypropylene, polyester, cellulose resin, and vinyl resin, with polyethylene resin being particularly preferred from the viewpoint of recyclability. Furthermore, the cap 46 may contain the above-mentioned additives as long as the characteristics of the present invention are not impaired.

[0087] As shown in FIG. 6, the cap may be of a screw type having a groove on the inner surface of cap 46 so as to screw into threaded thread 47 of extraction port 45, or it may be of a plug type which fits into extraction port 47 by plugging it.

[0088] In one embodiment, the packaging container of the present invention is a packaging bag. Examples of packaging bags include packaging bags of various shapes, such as standing pouch type, side seal type, two-sided seal type, three-sided seal type, four-sided seal type, envelope seal type, grommet seal type (pillow seal type), pleated seal type, flat bottom seal type, square bottom seal type, and gusset type.

[0089] In one embodiment, the packaging container of the present invention is a packaging bag 50 formed by bonding two laminates together as shown in FIG. 8 (the shaded areas are the heat-sealed areas).

[0090] A packaging bag 50 in the form shown in FIG. 8 can be produced by preparing two laminates 30, overlapping these laminates 30 with the first sealant layers 31 facing each other, and heat-sealing three sides.

[0091] In one embodiment, the packaging container of the present invention is a standing pouch type packaging bag 60 (hereinafter simply referred to as a standing pouch 60) as shown in FIG. The body 61 of the standing pouch 60 is made of the laminate 30 . The bottom 62 may also be made of the laminate 30. With such a configuration, the gas barrier properties of the standing pouch 60 can be further improved.

[0092] The body 61 can be formed by making a bag so that the first sealant layer 31 of the base material / laminate 30 becomes the innermost layer. In another embodiment, first, two sheets of the laminate 30 are prepared and then overlapped with the first sealant layers 31 facing each other. Next, two sheets of the laminate 30 folded in a V shape are inserted from both ends of the overlapped laminate 30 with the first sealant layers 31 facing outwards, and heat sealed to form the body 61 of the standing pouch 60. According to this production method, a standing pouch 60 having a body with side gussets can be obtained. The bottom 62 can be formed by inserting the laminate 30 between the body parts 61 that have been made into bags and heat sealing the laminate. More specifically, the bottom 62 can be formed by folding the laminate 30 into a V shape so that the first sealant layer 31 is on the outside, inserting the laminate 30 between the body parts 61 that have been made into bags, and heat sealing the laminate.

[0093] The packaging container may also be provided with easy-opening means 71 as shown in FIG. As shown in FIG. 8, examples of the easy-to-open means 71 include a notch 72 which serves as a starting point for tearing, and a half-cut line 73 formed by laser processing or a cutter as a path for tearing.

[0094] 9, the packaging container may include a steam release mechanism 80. The steam release mechanism 80 is configured to communicate the inside and outside of the packaging container when the steam pressure inside the packaging container reaches or exceeds a predetermined value, to release steam, and to suppress the steam from escaping at places other than the steam release mechanism 80. The steam release mechanism 80 comprises a steam release seal portion 80a protruding from the side seal portion toward the inside of the packaging container, and a non-sealed portion 80b isolated from the content-accommodating portion by the steam release seal portion 80a. The non-sealed portion 80b is connected to the outside of the packaging container. When the packaging container, which is filled with the contents and has a heat-sealed opening, is heated in a microwave oven or the like, the internal pressure increases and the steam-sealed portion 80a peels off. Steam passes through the peeled steam-sealed portion 80a and the non-sealed portion 70b and escapes to the outside of the packaging container. EXAMPLES

[0095] 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. The materials used in the following examples are as follows: Polyethylene resin A: Prime Polymer, SP0523A, m-C6-LLDPE, density 0.908g / cm 3 , melting point 104℃, MFR 2.0g / 10min Polyethylene resin B: Dow Chemical, ELITE5538G, MDPE, density 0.941g / cm 3 , melting point 129℃, MFR 1.3g / 10min Polyethylene resin C: Prime Polymer, SP2520, m-C6-LLDPE, density 0.925g / cm 3 , Melting point 122℃, MFR 1.9g / 10min Polyethylene resin D: Dow Chemical, ELITE5100G, HDPE, density 0.920g / cm 3 , melting point 122℃, MFR 0.85g / 10min Polyethylene resin E: Dow Chemical, Affinity PL1880G, m-C8-LLDPE, density 0.902g / cm 3, Melting point 99℃, MFR 1.0g / 10min Polyethylene resin a: Prime Polymer, HZ3300, density 0.950g / cm 3 , HDPE, melting point 132℃, MFR 1.1g / 10min Polyethylene resin b: Dow Chemical, ELITE5960G, HDPE, density 0.962g / cm 3 , Melting point 134℃, MFR 0.85g / 10min

[0096] Example 1-1 Polyethylene resin A and polyethylene resin B were co-extruded into a two-layer film by the inflation method, and then stretched 5 times in the longitudinal direction (MD) to produce a substrate 10 for forming a vapor-deposited film, comprising a first polyethylene resin layer 11 composed of polyethylene resin A and a second polyethylene resin layer 12 composed of polyethylene resin B. In the substrate 10 for formation of a deposited film, the first polyethylene resin layer 11 had a thickness of 2 μm, and the second polyethylene resin layer 12 had a thickness of 23 μm.

[0097] An aluminum vapor-deposited film having a thickness of 30 nm was formed by PVD on the first polyethylene resin layer 11 of the substrate 10 for forming a vapor-deposited film prepared as described above, to prepare a vapor-deposited substrate. The optical density (OD value) of the formed vapor-deposited film was measured and found to be 3.0.

[0098] Examples 1-2 to 1-4 and Comparative Examples 1-1 to 1-2 A substrate 10 for formation of a deposited film and a deposition substrate were prepared in the same manner as in Example 1-1, except that the polyethylene resin A used to form the first polyethylene resin layer 11 was changed to a polyethylene resin shown in Table 1.

[0099] <<Laminate strength evaluation>> Polyethylene resin C was extruded into a single layer by an inflation method to obtain an unstretched polyethylene resin film having a thickness of 100 μm. This unstretched polyethylene resin film was used as a first sealant layer 31 and laminated onto the deposition film 21 of the deposition base material obtained in the above Examples 1-1 to 1-4 and Comparative Examples 1-1 to 1-2 via a two-component curing urethane adhesive (RU-004 / H-1, manufactured by Rock Paint Co., Ltd.) to produce a laminate 30.

[0100] The laminate 30 produced as described above was cut into a rectangular shape having a width of 15 mm to prepare a test piece. The peel strength between the vapor-deposited film 21 and the first polyethylene resin layer 11 of this test piece was measured using a tensile tester (Tensilon universal material testing machine, manufactured by Orientec Co., Ltd.) in accordance with JIS K 6854-2. The measurement results are shown in Table 1. The peeling speed was 50 mm / min and the peeling angle was 180°.

[0101] Example 2-1 Polyethylene resin A, polyethylene resin B and polyethylene resin A were co-extruded by the inflation method to form a three-layer film, which was then stretched five times in the longitudinal direction (MD) to produce a substrate 10 for forming a vapor-deposited film, which comprises a first polyethylene resin layer 11 composed of polyethylene resin A, a second polyethylene resin layer 12 composed of polyethylene resin B, and a third polyethylene resin layer 13 composed of polyethylene resin A. In the substrate 10 for forming a deposited film, the first polyethylene resin layer 11 had a thickness of 2 μm, the second polyethylene resin layer 12 had a thickness of 21 μm, and the third polyethylene resin layer 13 had a thickness of 2 μm.

[0102] An aluminum vapor-deposited film having a thickness of 30 nm was formed by PVD on the first polyethylene resin layer 11 of the substrate 10 for forming a vapor-deposited film prepared as described above, to prepare a vapor-deposited substrate. The optical density (OD value) of the formed vapor-deposited film was measured and found to be 3.0.

[0103] Examples 2-2 to 2-4 and Comparative Examples 2-1 to 2-2 A substrate 10 for forming a vapor-deposited film and a vapor-deposited substrate were prepared in the same manner as in Example 2-1, except that the polyethylene resin A used to form the first polyethylene resin layer 11 and the third polyethylene resin layer 13 was changed to the polyethylene resin shown in Table 2.

[0104] <<Laminate strength evaluation>> Polyethylene resin C was extruded into a single layer by an inflation method to obtain an unstretched polyethylene resin film having a thickness of 100 μm. This unstretched polyethylene resin film was used as a first sealant layer 31 and laminated onto the deposition film 21 of the deposition substrate obtained in the above Examples 2-1 to 2-4 and Comparative Examples 2-1 to 2-2 via a two-component curing urethane adhesive (RU-004 / H-1, manufactured by Rock Paint Co., Ltd.) to produce a laminate 30.

[0105] The laminate 30 produced as described above was cut into a rectangular shape having a width of 15 mm to prepare a test piece. The peel strength between the vapor-deposited film 21 and the first polyethylene resin layer 11 of this test piece was measured using a tensile tester (Tensilon universal material testing machine, manufactured by Orientec Co., Ltd.) in accordance with JIS K 6854-2. The measurement results are shown in Table 2. The peeling speed was 50 mm / min and the peeling angle was 180°.

[0106] Example 3-1 Polyethylene resin A was extruded into a single layer by an inflation method and then stretched 5 times in the machine direction (MD) to prepare a substrate 10 for forming a deposited film comprising a first polyethylene resin layer 11 made of polyethylene resin A. In the substrate 10 for formation of a deposited film, the first polyethylene resin layer 11 had a thickness of 25 μm.

[0107] An aluminum vapor-deposited film having a thickness of 30 nm was formed by PVD on the first polyethylene resin layer 11 of the substrate 10 for forming a vapor-deposited film prepared as described above, to prepare a vapor-deposited substrate.

[0108] Examples 3-2 to 3-4 and Comparative Examples 3-1 to 3-2 A substrate 10 for formation of a deposited film and a deposition substrate were prepared in the same manner as in Example 3-1, except that the polyethylene resin A used to form the first polyethylene resin layer 11 was changed to a polyethylene resin shown in Table 3.

[0109] <<Laminate strength evaluation>> Polyethylene resin C was extruded into a single layer by an inflation method to obtain an unstretched polyethylene resin film having a thickness of 100 μm. This unstretched polyethylene resin film was used as a first sealant layer 31 and laminated onto the deposition film 21 of the deposition base material obtained in the above Examples 3-1 to 3-4 and Comparative Examples 3-1 to 3-2 via a two-component curing urethane adhesive (RU-004 / H-1, manufactured by Rock Paint Co., Ltd.) to produce a laminate 30.

[0110] The laminate 30 produced as described above was cut into a rectangular shape having a width of 15 mm to prepare a test piece. The peel strength between the vapor-deposited film 21 and the first polyethylene resin layer 11 of this test piece was measured using a tensile tester (Tensilon universal material testing machine, manufactured by Orientec Co., Ltd.) in accordance with JIS K 6854-2. The measurement results are shown in Table 3. The peeling speed was 50 mm / min and the peeling angle was 180°.

[0111] Example 4-1 Polyethylene resin A, polyethylene resin B, and polyethylene resin E are co-extruded by an inflation method to form a three-layer tube consisting of a layer (outer layer) composed of polyethylene resin A, a layer (middle layer) composed of polyethylene resin B, and a layer (inner layer) composed of polyethylene resin E, Next, the inner layers, each composed of polyethylene resin E, were pressed together using a rubber roll to obtain a five-layer film having a first polyethylene resin layer 11 composed of polyethylene resin A, a second polyethylene resin layer 12 composed of polyethylene resin B, a third polyethylene resin layer 13 composed of polyethylene resin E, a fourth polyethylene resin layer 14 composed of polyethylene resin B, and a fifth polyethylene resin layer 15 composed of polyethylene resin A. This film was stretched 5 times in the machine direction (MD) to prepare a substrate 10 for forming a deposited film. In the substrate 10 for forming a vapor-deposited film, the first polyethylene resin layer 11 had a thickness of 2 μm, the second polyethylene resin layer 12 had a thickness of 9.3 μm, the third polyethylene resin layer 13 had a thickness of 2.4 μm, the fourth polyethylene resin layer 14 had a thickness of 9.3 μm, and the fifth polyethylene resin layer 15 had a thickness of 2 μm.

[0112] An aluminum vapor-deposited film having a thickness of 30 nm was formed by PVD on the first polyethylene resin layer 11 of the substrate 10 for forming a vapor-deposited film prepared as described above, to prepare a vapor-deposited substrate. The optical density (OD value) of the formed vapor-deposited film was measured and found to be 3.0.

[0113] Examples 4-2 to 4-4 and Comparative Examples 4-1 to 4-2 A substrate 10 for forming a vapor-deposited film and a vapor-deposited substrate were prepared in the same manner as in Example 4-1, except that the polyethylene resin A used to form the first polyethylene resin layer 11 and the fifth polyethylene resin layer 15 was changed to the polyethylene resin shown in Table 4.

[0114] <<Laminate strength evaluation>> Polyethylene resin C was extruded into a single layer by an inflation method to obtain an unstretched polyethylene resin film having a thickness of 100 μm. This unstretched polyethylene resin film was used as a first sealant layer 31 and laminated onto the deposition film 21 of the deposition base material obtained in Examples 4-1 to 4-4 and Comparative Examples 4-1 to 4-2 above, via a two-component curing urethane adhesive (RU-004 / H-1, manufactured by Rock Paint Co., Ltd.) to produce a laminate 30.

[0115] The laminate 30 produced as described above was cut into a rectangular shape having a width of 15 mm to prepare a test piece. The peel strength between the vapor-deposited film 21 and the first polyethylene resin layer 11 of this test piece was measured using a tensile tester (Tensilon universal material testing machine, manufactured by Orientec Co., Ltd.) in accordance with JIS K 6854-2. The measurement results are shown in Table 4. The peeling speed was 50 mm / min and the peeling angle was 180°.

[0116] [Table 1]

[0117] [Table 2]

[0118] [Table 3]

[0119] [Table 4] [Explanation of symbols]

[0120] 10: substrate for forming vapor-deposited film, 11: first polyethylene resin layer, 12: second polyethylene resin layer, 13: third polyethylene resin layer, 14: fourth polyethylene resin layer, 15: fifth polyethylene resin layer, 20: vapor-deposited substrate, 21: vapor-deposited film, 30: laminate, 31 first sealant layer, 32: second sealant layer, 40: laminated tube, 41: laminated tube body, 42: head, 43: body, 44: shoulder, 45: pouring outlet, 46: cap, 47: thread, 48: welded portion, 49: bottom seal portion, 50: packaging bag, 60: standing pouch, 61: body, 62: bottom, 71: easy-opening means, 72: notch portion, 73: half-cut line, 80: steam release mechanism, 80a: steam release seal portion, 80b: non-sealed portion

Claims

1. A substrate for forming a deposited film is used as the substrate in a laminate including at least a deposited substrate including a substrate and a deposited film, and a heat seal layer, The substrate for forming a deposited film has a multilayer structure, Each layer constituting the substrate for forming a deposited film is made of a polyethylene resin, The density of the polyethylene resin constituting each layer is different, Among the layers, the density of the polyethylene resin constituting the first polyethylene resin layer constituting the surface on which the deposited film of the substrate for deposition film formation is to be formed is 0.943 g / cm ３ is as follows: The substrate for forming a deposited film is characterized in that the substrate for forming a deposited film has been subjected to a stretching treatment.

2. 2. The substrate for formation of a deposited film according to claim 1, wherein the polyethylene resin constituting each of the layers has a different density and has a density gradient.

3. The density difference between the polyethylene resins constituting the layers is 0.05 g / cm ３ The substrate for forming a deposited film according to claim 1 or 2, which is as follows:

4. A deposition substrate including at least a substrate and a deposition film, The substrate is made of the substrate for forming a deposited film according to any one of claims 1 to 3, The deposition film is provided on a first polyethylene resin layer of the substrate for forming a deposition film,

5. A laminate including at least a substrate, a vapor-deposited film, and a first sealant layer, The substrate is made of the substrate for forming a deposited film according to any one of claims 1 to 3, the vapor-deposited film is provided on a first polyethylene resin layer of the substrate for forming a vapor-deposited film, A laminate, wherein the first sealant layer is made of a polyethylene resin.

6. A second sealant layer is further provided on a surface of the substrate opposite to the surface on which the first sealant layer is provided, The laminate of claim 5 wherein the second sealant layer is comprised of a polyethylene resin.

7. The laminate according to claim 5 or 6, further comprising a barrier coat layer between the first sealant layer and the vapor-deposited film.

8. The laminate according to any one of claims 5 to 7, which is used for a packaging container.

9. The laminate according to any one of claims 5 to 8, wherein the content of the polyethylene resin in the entire laminate is 80 mass% or more.

10. A packaging container comprising the laminate according to any one of claims 5 to 9.

11. The packaging container according to claim 10, which is a laminated tube.

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