Laminate, packaging bag, and bag-in-box

Abstract

To provide a film that has excellent flexibility and achieves a decrease in blocking even during storage at room temperature, a laminate, a packaging bag composed of the laminate, and a bag-in-box having the packaging bag.SOLUTION: A film contains a polyethylene resin composition containing a linear ethylenic copolymer (A) and a low-density polyethylene (B) and a modifier.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a film, a laminate, a packaging bag, and a bag-in-box. [Background technology]

[0002] Due to their versatility, films are used for packaging a variety of products, including food, medicines, cosmetics, and chemicals. Patent Document 1 discloses a sealant film that combines low-temperature sealing properties with boilability up to 100°C. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 11-320786 Summary of the Invention [Problem to be solved by the invention]

[0004] However, conventional films have a problem in that blocking occurs during storage when they are stored in roll form at room temperature after production, particularly in temperatures around 40°C in the summer.

[0005] In recent years, bag-in-box containers have been used as containers for transporting liquids, etc. Bag-in-box containers are containers in which a double-layered interior packaging film (inner bag) with a spout is housed in an exterior cardboard box or the like. The film is required to have flexibility that can withstand the bending movement during transportation in a bag-in-box or the like.

[0006] The present invention aims to provide a film and laminate that are highly flexible and exhibit reduced blocking even during storage at room temperature, a packaging bag made of the laminate, and a bag-in-box that includes the packaging bag. [Means for solving the problem]

[0007] According to one aspect of the present invention, there is provided a film comprising a polyethylene resin composition containing a linear ethylene copolymer (A) and a low-density polyethylene (B), and a modifier.

[0008] The film according to one embodiment of the present invention further has a density of 930 kg / m 3 The following polyethylenes may be contained:

[0009] In the film according to one aspect of the present invention, the content of the polyethylene resin composition may be 5% by mass or more and less than 100% by mass.

[0010] In the film according to one aspect of the present invention, the content of the modifier may be 2% by mass or more and 60% by mass or less.

[0011] In the film according to one aspect of the present invention, the modifier may be an ethylene-α-olefin copolymer.

[0012] The film according to one embodiment of the present invention may further contain 0.01% by mass or more of an antiblocking agent.

[0013] The film according to one aspect of the present invention may contain a plurality of types of the polyethylene resin compositions.

[0014] The film according to one aspect of the present invention may contain a plant-derived resin.

[0015] The film according to one embodiment of the present invention may be a single layer film.

[0016] According to one aspect of the present invention, there is provided a laminate having a plurality of layers, at least one of which is a film according to one aspect of the present invention.

[0017] In the laminate according to one aspect of the present invention, the content of the polyethylene resin composition in the laminate may be 5% by mass or more and less than 100% by mass.

[0018] In the laminate according to one aspect of the present invention, the content of the modifier in the laminate may be 0.5% by mass or more and 60% by mass or less.

[0019] The laminate according to one aspect of the present invention may have a first outermost layer and a second outermost layer, and at least one of the first outermost layer and the second outermost layer may be the film.

[0020] A laminate according to one embodiment of the present invention has an intermediate layer between the first outermost layer and the second outermost layer, and the first outermost layer, the second outermost layer, and the intermediate layer may be the film.

[0021] In one embodiment of the laminate of the present invention, the modifier in the first outermost layer and the intermediate layer may be an ethylene-α-olefin copolymer, and the modifier in the second outermost layer may be a styrene-based elastomer.

[0022] In the laminate according to one aspect of the present invention, a thermal adhesion strength between the first outermost layer and the second outermost layer may be 0 to 1.2 kgf / 50 mm.

[0023] The laminate according to one aspect of the present invention may have a pinhole count of 1.0 pinholes / A4 or less when measured at −20° C. and 1500 times using a Gelbo flex tester.

[0024] In the laminate according to one aspect of the present invention, the loop stiffness of the laminate may be 10 N / 15 mm or less.

[0025] The laminate according to one aspect of the present invention may contain a plant-derived resin.

[0026] According to one aspect of the present invention, there is provided a packaging bag made of the laminate according to one aspect of the present invention.

[0027] According to one aspect of the present invention, there is provided a bag-in-box including a packaging bag according to one aspect of the present invention. [Effects of the Invention]

[0028] According to one aspect of the present invention, it is possible to provide a film, a laminate, a packaging bag made of the laminate, and a bag-in-box including the packaging bag, which are highly flexible and exhibit reduced blocking even during storage at room temperature. [Brief explanation of the drawings]

[0029] [Figure 1] 1 is a cross-sectional schematic view of a film according to one embodiment of the present invention. [Figure 2] 1 is a cross-sectional schematic view of a laminate according to one embodiment of the present invention. [Figure 3] 1 is a schematic diagram of a packaging bag according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0030] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In this specification and drawings, components having substantially the same functional configurations are designated by the same reference numerals, and redundant explanations will be omitted.

[0031] [First embodiment] In the first embodiment, a film according to one aspect of the present invention and a laminate according to one aspect of the present invention having the film will be described.

[0032] (film) 1 is a schematic cross-sectional view of a film 1 according to this embodiment. The film 1 according to this embodiment may be used as a single layer film, or may be used as at least one layer of a laminate having multiple layers, such as laminate 50 (FIG. 2) described below. The film 1 contains a polyethylene resin composition and a modifier.

[0033] Polyethylene resin composition The polyethylene resin composition contains a linear ethylene copolymer (A) and a low-density polyethylene. The content of the linear ethylene copolymer (A) in the polyethylene resin composition is preferably 70% by mass or more and 95% by mass or less, and more preferably 75% by mass or more and 90% by mass or less. The content of the low-density polyethylene (B) in the polyethylene resin composition is preferably 5% by mass or more and 30% by mass or less, and more preferably 10% by mass or more and 25% by mass or less. By setting the contents of the linear ethylene copolymer (A) and the low-density polyethylene (B) in the polyethylene resin composition within these ranges, blocking of the film 1 according to this embodiment and blocking of the laminate 50 can be further suppressed.

[0034] Linear ethylene copolymer (A) The linear ethylene copolymer (A) is a copolymer of ethylene and at least one kind of α-olefin (hereinafter, sometimes referred to as "ethylene-α-olefin copolymer (a)"). The carbon number of the α-olefin in the linear ethylene copolymer (A) is preferably 4 to 10, and more preferably 6 to 10. Examples of the α-olefin having 4 to 10 carbon atoms include 1-butene, 1-hexene, 1-pentene, 4-methyl-1-pentene, 1-heptene, 1-octene, and 1-decene. The linear ethylene copolymer (A) is preferably an ethylene-1-hexene copolymer.

[0035] The linear ethylene copolymer (A) has a density of 894 kg / m 3 More than 914kg / m 3 Preferably, it is 895 kg / m or less. 3 More than 912kg / m 3 More preferably, it is 896 kg / m or less. 3More than 910kg / m 3 It is more preferable that the density of the linear ethylene copolymer (A) is 894 kg / m or less. 3 If the density of the linear ethylene copolymer (A) is 914 kg / m or more, the blocking phenomenon can be suppressed without increasing the self-adhesiveness of the film 1. 3 If it is equal to or less than this, the melting point of the linear ethylene copolymer (A) will not be too high, and the low-temperature heat sealability of the film 1 will be good. The density in this specification can be measured in accordance with JIS K7112 1999.

[0036] The linear ethylene copolymer (A) preferably has an MFR (Melt Flow Rate) of 0.1 g / 10 min to 250 g / 10 min, more preferably 1 g / 10 min to 150 g / 10 min, even more preferably 2 g / 10 min to 20 g / 10 min, and particularly preferably 3 g / 10 min to 10 g / 10 min. When the MFR is within the above range, the processability of the film 1 is good. Unless otherwise specified, the MFR in this specification can be measured in accordance with ASTM D1238-89 at a measurement temperature of 190°C and a load of 2.16 kg.

[0037] The linear ethylene copolymer (A) may contain multiple types of ethylene-α-olefin copolymers (a). In this case, the multiple types of ethylene-α-olefin copolymers (a) may have different α-olefin units, different densities, or different MFRs, for example. When the linear ethylene copolymer (A) contains a plurality of ethylene-α-olefin copolymers (a) having different densities and / or MFRs, the density and / or MFR of each ethylene-α-olefin copolymer (a) may be appropriately adjusted so that the density and / or MFR of the linear ethylene copolymer (A) falls within the above-mentioned range.

[0038] The linear ethylene copolymer (A) can be produced by a gas phase polymerization reaction using a metallocene catalyst. When the linear ethylene copolymer (A) contains multiple types of ethylene-α-olefin copolymers (a), the linear ethylene copolymer (A) may be produced by homopolymerizing each ethylene-α-olefin copolymer (a) and then mixing or melt-kneading them by a conventionally known method, or the linear ethylene copolymer (A) may be produced by multistage polymerization of multiple types of ethylene-α-olefin copolymers (a), or by polymerizing multiple types of ethylene-α-olefin copolymers (a) in the same polymerization vessel in the presence of multiple metallocene catalysts.

[0039] Low-density polyethylene (B) The low-density polyethylene (B) is not particularly limited as long as it is low-density polyethylene (LDPE), but it preferably satisfies the following requirements and is preferably low-density polyethylene polymerized by a high-pressure method.

[0040] Requirements: The intrinsic viscosity [η] (dl / g) measured in decalin at 135°C and the weight average molecular weight (GMw) measured by gel permeation chromatography-viscosity detector (GPC-VISCO) preferably satisfy the following relationship (R-1), and more preferably satisfy the following relationship (R-2): Relational formula (R-1): 0.55×10 -4 ≦[η] / 〔(GMw)×0.776〕≦2.0×10 -4 Relationship (R-2): 0.70×10 -4 ≦[η] / 〔(GMw)×0.776〕≦1.8×10 -4

[0041] It is known that when long chain branches are introduced into low-density polyethylene, the intrinsic viscosity [η] (dl / g) becomes smaller than that of linear low-density polyethylene of the same molecular weight but without long chain branches (for example, Walther Burchard, ADVANCES IN POLYMER SCIENCE, 143, Branched Polymer II, p. 137 (1999)). Therefore, low-density polyethylene (B) that satisfies the above requirements has many long chain branches and is therefore excellent in moldability and flowability.

[0042] The value of [η] / [(GMw)×0.776] can be increased or decreased, for example, by increasing or decreasing the amount of long chain branches introduced into the low-density polyethylene (B) by a conventionally known method. The low-density polyethylene (B) may be an ethylene homopolymer, or an ethylene copolymer containing units derived from ethylene and a small amount of units derived from other polymerizable monomers (for example, containing 20% ​​by mass or less of units derived from vinyl acetate, acrylic esters, etc.). When the low-density polyethylene (B) is an ethylene copolymer, it can be confirmed whether the low-density polyethylene (B) is an ethylene copolymer by, for example, checking the peak shape and melting point by DSC, checking and structural analysis of the infrared absorption spectrum by FT-IR, or by NMR or the like.

[0043] Low-density polyethylene (B) has a density of 935 kg / m 3 Preferably, it is 930 kg / m or less. 3 Less than or equal to 920 kg / m 3 or less, more preferably 910 kg / m 3 The lower limit is not particularly limited, but is usually 870 kg / m 3 is.

[0044] The polyethylene resin composition may contain, as necessary, various additives that are usually added to polyolefins, such as weather stabilizers, heat stabilizers, antistatic agents, anti-fogging agents, anti-blocking agents, slip agents, lubricants, pigments, and anti-dripping agents. It is also preferred that the polyethylene resin composition consists of only the linear ethylene copolymer (A) and the low-density polyethylene (B).

[0045] The polyethylene resin composition has a density of 896 kg / m 3 More than 912kg / m 3 The density of the polyethylene resin composition is preferably 898 kg / m or less. 3 More than 910kg / m 3 More preferably, it is 900 kg / m or less. 3 More than 908kg / m 3 The following is the result.

[0046] The polyethylene resin composition preferably has an MFR of 1 g / 10 min or more and 20 g / 10 min or less, and more preferably has an MFR of 2 g / 10 min or more and 15 g / 10 min or less.

[0047] When film 1 is used as a single layer, the content of the polyethylene resin composition in the single layer film 1 is preferably 5% by mass or more and less than 100% by mass, more preferably 15% by mass or more and less than 100% by mass, even more preferably 30% by mass or more and less than 100% by mass, and even more preferably 40% by mass or more and less than 100% by mass. When the content of the polyethylene resin composition in the single-layer film 1 is 5% by mass or more, the blocking resistance is excellent. When the content of the polyethylene resin composition in the single-layer film 1 is 100% by mass, the desired physical properties cannot be obtained, which is not preferable.

[0048] The film 1 may contain only one type of polyethylene resin composition, or may contain multiple types of polyethylene resin compositions.

[0049] Modifier The modifier is not particularly limited, but examples thereof include α-olefin copolymers such as ethylene-α-olefin copolymers, and styrene-based elastomers, with ethylene-α-olefin copolymers being preferred. Examples of the ethylene-α-olefin copolymer include an ethylene-1-butene copolymer, an ethylene-1-hexene copolymer, and an ethylene-1-octene copolymer, with an ethylene-1-butene copolymer or an ethylene-1-octene copolymer being preferred, and an ethylene-1-octene copolymer being more preferred. As the styrene-based elastomer, a hydrogenated styrene block copolymer is preferred.

[0050] When the modifier is an ethylene-α-olefin copolymer, the density of the modifier is 800 kg / m 3 More than 900kg / m 3 It is preferable that the saturation is 810 kg / m or less. 3 More than 890kg / m 3 More preferably, it is: When the modifier is a styrene-based elastomer, the density of the modifier is 800 kg / m 3 More than 950kg / m 3 Preferably, it is 850 kg / m or less. 3 More than 920kg / m 3 More preferably, it is:

[0051] The MFR of the modifier is preferably 0.5 g / 10 min or more and 20.0 g / 10 min or less, and more preferably 0.7 g / 10 min or more and 15.0 g / 10 min or less. When the MFR is within the above range, moldability is good. In the case of styrene-based elastomers, the measurement can be performed in accordance with ASTM D1238-89 at a measurement temperature of 230°C and a load of 2.16 kg. When the modifier is an ethylene-α-olefin copolymer, the MFR of the modifier is preferably 0.5 g / 10 min or more and 10.0 g / 10 min or less. When the MFR is within the above range, the moldability is good.

[0052] When an ethylene-α-olefin copolymer is used as the modifier, the melting point of the modifier is preferably 100° C. or lower, more preferably 90° C. or lower, and even more preferably 80° C. or lower. When an ethylene-α-olefin copolymer is used as the modifier, the lower limit of the melting point of the modifier is not particularly limited, but is, for example, 20° C.

[0053] When film 1 is used as a single layer, the content of the modifier in the single layer film 1 is preferably 2% by mass or more and 60% by mass or less, more preferably 4% by mass or more and 50% by mass or less, even more preferably 5% by mass or more and 40% by mass or less, particularly preferably 6% by mass or more and 30% by mass or less, and most preferably 7% by mass or more and 20% by mass or less. If the content of the modifier in the single-layer film 1 is 2% by mass or more, the physical properties such as loop rigidity and Gelbo can be set within the preferred ranges described below. If the content of the modifier in the film 1 exceeds 60% by mass, the blocking resistance decreases.

[0054] In addition to the polyethylene resin composition and modifier, the film 1 contains a polyethylene-based resin having a density of 930 kg / m 3 The following polyethylene may further be contained. In this case, the polyethylene may be an ethylene homopolymer or a copolymer of ethylene and another α-olefin monomer, and is preferably an ethylene homopolymer. The density of the polyethylene is preferably 920 kg / m 3 Less than or equal to 910 kg / m 3 The lower limit of the density of polyethylene is not particularly limited, but is, for example, 870 kg / m 3 is. Density of film 1: 930 kg / m 3The content of the following polyethylene is more than 0% by mass and not more than 70% by mass, preferably not less than 10% by mass and not more than 60% by mass, and more preferably not less than 20% by mass and not more than 50% by mass.

[0055] The film 1 may also contain additives such as an antiblocking agent, ultra-high molecular weight polyethylene, and acrylic beads. The film 1 preferably contains an antiblocking agent. There are no particular limitations on the antiblocking agent, but it is preferable to use various antiblocking agents containing silicon dioxide. The content of the antiblocking agent in the film 1 is preferably 0.01% by mass or more and 20% by mass or less, more preferably 0.1% by mass or more and 15% by mass or less, and even more preferably 0.3% by mass or more and 12% by mass or less. In the film 1, even if the content of the antiblocking agent is small, the antiblocking effect can be obtained.

[0056] The film 1 may also contain a plant-derived resin. In this case, at least a portion of the above components may be a plant-derived resin. The plant-derived resin may be, for example, one or more selected from biopolyethylene, biopolypropylene, biopolyethylene terephthalate, etc., and biopolyethylene is more preferably used. The film 1 contains a plant-derived resin, which reduces the environmental impact.

[0057] When film 1 is used as a single layer, the thermal adhesion strength between the front surface of film 1 and the back surface of film 1 is preferably 0 or more and 1.2 kgf / 50 mm or less, more preferably 1.0 kgf / 50 mm or less, and even more preferably 0.8 kgf / 50 mm or less. If the thermal adhesion strength between the front and back surfaces is within the above range, blocking can be prevented when the film 1 is stored in the form of a roll. In this specification, the thermal adhesion strength of the film 1 is a value measured within 30 minutes after the production of the film 1. The thermal adhesion strength can be measured in accordance with the examples described later.

[0058] When film 1 is used as a single layer, it is preferable that the number of pinholes generated in film 1 measured at -20°C and 1500 times (condition 1) using a Gelbo flex tester is 1.0 pinholes or less per A4 size (1.0 pinholes or less per A4 size). If the number of pinholes generated in film 1 measured under the above condition 1 is within the above range, film 1 has excellent flex resistance. Furthermore, when film 1 is used as a single layer, it is more preferable that the number of pinholes generated in film 1 measured at -20°C and 5,000 times (condition 2) using a Gelbo flex tester is 10 or less per A4 size (10 or less per A4 size). If the number of pinholes generated in film 1 measured under the above condition 2 is within the above range, film 1 has better flex resistance. In this specification, the number of pinholes generated in Film 1 under both Condition 1 and Condition 2 is a value measured within 20 days after the production of Film 1.

[0059] When film 1 is used as a single layer, the number of pinholes generated in film 1 measured under the above condition 1 is preferably 1.0 pinholes / A4 or less, more preferably 0.5 pinholes / A4 or less, and even more preferably 0 pinholes / A4. When film 1 is used as a single layer, the number of pinholes occurring in film 1 measured under the above condition 2 is preferably 6 or less per A4 sheet, more preferably 3 or less per A4 sheet, even more preferably 1 or less per A4 sheet, and even more preferably 0 or less per A4 sheet.

[0060] When film 1 is used as a single layer, the loop stiffness in at least one of MD (machine direction) and TD (transverse direction) is preferably 10 N / 15 mm or less, more preferably 6 N / 15 mm or less, more preferably 4 N / 15 mm or less, and more preferably 3 N / 15 mm or less. Also, the loop stiffness in both MD and TD of film 1 is preferably 10 N / 15 mm or less, more preferably 6 N / 15 mm or less, more preferably 4 N / 15 mm or less, and more preferably 3 N / 15 mm or less. If the loop stiffness is within the above range, the film 1 will have excellent flexibility. In this specification, the loop stiffness of the film 1 is a value measured within 20 days after the film 1 is produced.

[0061] The thickness of the film 1 is not particularly limited. The thickness of the film 1 is set appropriately depending on the application. The thickness of the film 1 is, for example, 1 μm or more and 1000 μm or less, more preferably 5 μm or more and 500 μm or less, even more preferably 12 μm or more and 300 μm or less, still more preferably 20 μm or more and 150 μm or less, and particularly preferably 30 μm or more and 100 μm or less.

[0062] The surface roughness Ra of at least one of the front and back surfaces of the film 1 is usually 0.1 μm or more. If the surface roughness Ra is 0.1 μm or more, the surface becomes smooth, which can suppress thermal adhesion. On the other hand, if the surface roughness Ra is 0.8 μm or less, for example, the transmittance of the film 1 does not decrease, making it suitable for use when transparency is important. Therefore, the surface roughness Ra is preferably 0.2 μm or more and 0.8 μm or less, more preferably 0.2 μm or more and 0.5 μm or less. The surface roughness Ra in this specification is measured using a Handysurf, specifically by the method described in the examples.

[0063] The method for producing the film 1 is not particularly limited. Examples of methods for producing the film 1 include a method of preparing a composition (resin composition for film) containing a polyethylene resin composition and a modifier, and, if desired, a resin or resin composition other than the polyethylene resin composition described above, and additives, and then subjecting this composition to inflation molding or extrusion molding, and a method of dissolving or dispersing the composition in a suitable solvent to prepare a coating liquid and coating this coating liquid onto a support (for example, an intermediate layer described below).

[0064] (Laminate) FIG. 2 shows a schematic cross-sectional view of a laminate 50 according to this embodiment. The laminate 50 is a laminate having three layers: a first outermost layer 10 , an intermediate layer 20 , and a second outermost layer 30 .

[0065] In the laminate 50, it is preferable that at least one of the first outermost layer 10, the intermediate layer 20, and the second outermost layer 30 is a film 1 according to this embodiment, it is more preferable that at least one of the first outermost layer 10 and the second outermost layer 30 is a film 1 according to this embodiment, and it is even more preferable that both the first outermost layer 10 and the second outermost layer 30 are films 1 according to this embodiment.

[0066] In the laminate 50, it is also preferable that the first outermost layer 10, the intermediate layer 20, and the second outermost layer 30 are all the film 1 according to this embodiment. In this case, the modifier in each layer may be any of the modifiers described above.

[0067] In the laminate 50, when at least one of the first outermost layer 10 and the second outermost layer 30 is a film 1 according to this embodiment, the content of the modifier in the first outermost layer 10 and / or the second outermost layer 30 is preferably 2% by mass or more and 60% by mass or less, more preferably 4% by mass or more and 50% by mass or less, even more preferably 5% by mass or more and 40% by mass or less, particularly preferably 6% by mass or more and 30% by mass or less, and most preferably 7% by mass or more and 20% by mass or less. In the laminate 50, when both the first outermost layer 10 and the second outermost layer 30 are films 1 according to this embodiment, it is preferable that the content of the modifier in at least one of the first outermost layer 10 and the second outermost layer 30 satisfies the above range.

[0068] Furthermore, in the laminate 50, when at least the intermediate layer 20 is the film 1 according to this embodiment, the content of the modifier in the intermediate layer 20 is preferably 2% by mass or more and 60% by mass or less, more preferably 4% by mass or more and 55% by mass or less, even more preferably 5% by mass or more and 50% by mass or less, particularly preferably 6% by mass or more and 46% by mass or less, and most preferably 7% by mass or more and 35% by mass or less.

[0069] In the laminate 50, the content (total amount) of the polyethylene resin composition in all the layers constituting the laminate 50 is preferably 5% by mass or more and less than 100% by mass, more preferably 15% by mass or more and less than 100% by mass, even more preferably 30% by mass or more and less than 100% by mass, and even more preferably 40% by mass or more and less than 100% by mass.

[0070] In the laminate 50, the content (total amount) of the modifier in all the layers constituting the laminate 50 is preferably 0.5% by mass or more and 60% by mass or less, more preferably 4% by mass or more and 54% by mass or less, even more preferably 5% by mass or more and 47% by mass or less, particularly preferably 6% by mass or more and 41% by mass or less, and most preferably 8% by mass or more and 35% by mass or less. In this case, the compounding ratio of the modifier may not be uniform among the layers, but may vary. When the laminate 50 is a laminate including a plurality of films 1 according to this embodiment, it is preferable that the modifier be contained in a larger amount in the intermediate layer 20 than in the other layers.

[0071] When a plurality of films 1 according to this embodiment are contained in the laminate 50, the polyethylene resin compositions in the films 1 may be the same as or different from each other.

[0072] Of the multiple layers constituting the laminate 50, the material of the layers other than the film 1 according to this embodiment is not particularly limited. For example, when the first outermost layer 10 is the film 1 according to the present embodiment and the intermediate layer 20 and the second outermost layer 30 are layers other than the film 1 according to the present embodiment, the intermediate layer 20 and the second outermost layer 30 are preferably made of resin. In this case, the intermediate layer 20 and the second outermost layer 30 may contain various additives.

[0073] When the intermediate layer 20 and the second outermost layer 30 are made of resin, examples of the resin include polyolefin resin, nylon resin, and polyester resin. Examples of polyolefin resins include polyethylene resins, polypropylene resins, and ethylene-α-olefin copolymers. Examples of polypropylene resins include homopolypropylene (HPP), random polypropylene (RPP), and block polypropylene (BPP). Examples of polyethylene resins include high density polyethylene (HDPE) and (linear) low density polyethylene (LDPE). Examples of nylon resins include nylon 6, nylon 8, nylon 11, nylon 12, nylon 6,6, nylon 6,10, and nylon 6,12. Examples of polyester resins include polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate.

[0074] When the intermediate layer 20 and the second outermost layer 30 are made of resin, the resin is preferably a polyethylene resin or an ethylene-α-olefin copolymer. Examples of α-olefins in this case include 1-butene, 1-hexene, 1-pentene, 4-methyl-1-pentene, 1-heptene, 1-octene, and 1-decene. When the intermediate layer 20 and the second outermost layer 30 are made of resin, the resin is more preferably a polyethylene resin or an ethylene-1-hexene copolymer, and even more preferably a polyethylene resin.

[0075] When the intermediate layer 20 and the second outermost layer 30 are made of resin, the resin intermediate layer 20 and the resin second outermost layer 30 preferably contain a modifier. In this case, the content (total amount) of the modifier in all layers constituting the laminate 50 is preferably 0.5% by mass to 60% by mass, more preferably 4% by mass to 54% by mass, even more preferably 5% by mass to 47% by mass, particularly preferably 6% by mass to 41% by mass, and most preferably 8% by mass to 35% by mass. The blending ratio of the modifier may not be uniform among the layers and may vary, but it is preferred that the intermediate layer 20 contains more modifier than the other layers.

[0076] When the second outermost layer 30 is made of resin, it preferably contains an antiblocking agent.

[0077] The laminate 50 may contain a plant-derived resin. In this case, the layer that is the film 1 according to this embodiment may contain a plant-derived resin as described above, or a layer that is not the film 1 according to this embodiment may contain a plant-derived resin, or both of these layers may contain a plant-derived resin. As the plant-derived resin, for example, one or more selected from biopolyethylene, biopolypropylene, biopolyethylene terephthalate, etc. can be suitably used, and biopolyethylene can be more suitably used.

[0078] In the laminate 50, the thermal adhesion strength between the first outermost layer 10 and the second outermost layer 30 is preferably 0 or more and 1.2 kgf / 50 mm or less, more preferably 1.0 kgf / 50 mm or less, and even more preferably 0.8 kgf / 50 mm or less. If the thermal adhesion strength between the first outermost layer 10 and the second outermost layer 30 is within the above range, blocking can be prevented when the laminate 50 is stored in the form of a roll. In this specification, the thermal adhesion strength of the laminate 50 is a value measured within 30 minutes after the production of the laminate 50. The thermal adhesion strength can be measured in the same manner as in the examples described later.

[0079] The number of pinholes occurring in the laminate 50, measured using a Gelbo flex tester under the above-mentioned condition 1, is preferably 1.0 pinholes / A4 or less. If the number of pinholes occurring in the laminate 50, measured under the above-mentioned condition 1, is within the above range, the laminate 50 has superior flex resistance. Furthermore, it is more preferable that the number of pinholes occurring in the laminate 50, measured using a Gelbo flex tester under the above-mentioned condition 2, is 10 or less per A4 size (10 or less per A4 size). If the number of pinholes occurring in the laminate 50, measured under the above-mentioned condition 2, is within the above range, the laminate 50 has better flex resistance. In this specification, the number of pinholes generated in the laminate 50 under both Condition 1 and Condition 2 is a value measured within 20 days after the laminate 50 was produced.

[0080] The number of pinholes generated in the laminate 50 measured under the above condition 1 is preferably 1.0 pinholes / A4 or less, more preferably 0.5 pinholes / A4 or less, and even more preferably 0 pinholes / A4. The number of pinholes occurring in the laminate 50 measured under the above condition 2 is preferably 6 or less per A4 size, more preferably 3 or less per A4 size, even more preferably 1 or less per A4 size, and even more preferably 0 or less per A4 size.

[0081] The loop stiffness of the laminate 50 in at least one of the MD and TD is preferably 10 N / 15 mm or less, more preferably 6 N / 15 mm or less, more preferably 4 N / 15 mm or less, and more preferably 3 N / 15 mm or less.The loop stiffness of the laminate 50 in both the MD and TD is also preferably 10 N / 15 mm or less, more preferably 6 N / 15 mm or less, more preferably 4 N / 15 mm or less, and more preferably 3 N / 15 mm or less. If the loop stiffness is within the above range, the laminate 50 will have excellent flexibility. In this specification, the loop stiffness of the laminate 50 is a value measured within 20 days after the laminate 50 is produced.

[0082] There are no particular limitations on the overall thickness of the laminate 50. The overall thickness of the laminate 50 is set appropriately depending on the application. The overall thickness (total thickness) of the laminate 50 is, for example, 1 μm or more and 1000 μm or less, more preferably 10 μm or more and 500 μm or less, even more preferably 20 μm or more and 200 μm or less, and particularly preferably 30 μm or more and 100 μm or less.

[0083] The surface roughness Ra of at least one of the surfaces of the first outermost layer 10 (the surface opposite to the surface in contact with the intermediate layer 20) and the second outermost layer 30 (the surface opposite to the surface in contact with the intermediate layer 20) of the laminate 50 is typically 0.1 μm or more. A surface roughness Ra of 0.1 μm or more can suppress thermal adhesion due to a smooth surface. On the other hand, a surface roughness Ra of 0.8 μm or less does not reduce the transmittance of the laminate 50, making it suitable for use when transparency is important. Therefore, the surface roughness Ra is preferably 0.2 μm or more and 0.8 μm or less, more preferably 0.2 μm or more and 0.5 μm or less.

[0084] The method for producing the laminate 50 is not particularly limited. Examples of methods for manufacturing the laminate 50 include inflation molding or co-extrusion of the material for the first outermost layer 10, the material for the intermediate layer 20, and the material for the second outermost layer 30; a method in which the first outermost layer 10 is extruded and laminated onto one side of a pre-manufactured intermediate layer 20, and the material for the second outermost layer 30 is extruded and laminated onto the other side of the intermediate layer 20; a method in which a film corresponding to the first outermost layer 10, a film corresponding to the intermediate layer 20, and a film corresponding to the second outermost layer 30 are bonded together and laminated; and a method in which a coating liquid containing the material for the first outermost layer 10 is coated onto one side of a pre-manufactured intermediate layer 20, and a coating liquid containing the material for the second outermost layer 30 is coated onto the other side of the intermediate layer 20.

[0085] (packaging bag) Next, a packaging bag having a laminate according to one embodiment of the present invention will be described. FIG. 3 shows a schematic diagram of a packaging bag 100 according to this embodiment. The packaging bag 100 includes a bag body 110 having a first surface 111 and a second surface 112 facing each other. The bag body 110 is formed using the laminate 50 according to this embodiment. In this embodiment, two laminates 50 are joined together at the side seal portions 121, 122 and the bottom seal portion 130 by heat sealing or the like, thereby forming the bag body 110 having a first surface 111 and a second surface 112. The film on the inner surface (contents side) of the bag body 110 of the packaging bag 100 is preferably the film 1 according to this embodiment.

[0086] The packaging bag 100 may be, for example, a packaging bag with zipper tape by forming a zipper tape at the opening 140. In addition, the packaging bag 100 may be formed by attaching a spout to one of the laminates 50 forming the first surface 111 and the laminates 50 forming the second surface 112, and then joining the peripheries of these laminates 50 together by heat sealing or the like.

[0087] Examples of items that can be packaged in the packaging bag 100 include food products, seasonings, food ingredients, beverages, medicines, blood, cosmetics, detergents, nutrients, chemicals, adhesives, pressure sensitive adhesives, paints, pesticides, and fertilizers. The packaging bag 100 has excellent flexibility and can therefore be preferably used as a packaging bag for a bag-in-box. A bag-in-box equipped with the packaging bag 100 as an inner bag can withstand bending movements during transportation of packaged items due to the excellent flexibility of the packaging bag.

[0088] (Effects of this embodiment) The film 1 and laminate 50 according to this embodiment are highly flexible and do not block even when stored at room temperature. Furthermore, the packaging bag and bag-in-box according to this embodiment are made of such a film and laminate, and therefore can withstand bending movements during transportation.

[0089] [Modification] The present invention is not limited to the above embodiment. For example, in the first embodiment above, a laminate 50 is exemplified in which at least one, preferably both, of the first outermost layer 10 and the second outermost layer 30 is a film 1 according to the first embodiment, but the first outermost layer 10, the intermediate layer 20, and the second outermost layer 30 may all be a film 1 according to the first embodiment.

[0090] For example, in the first embodiment described above, a laminate 50 having a three-layer structure of a first outermost layer 10, an intermediate layer 20, and a second outermost layer 30 is exemplified, but the laminate may also have a multi-layer structure of two layers or four or more layers.

[0091] Further, for example, in the first embodiment, the packaging bag 100 formed using the laminate 50 is exemplified, but the packaging bag may be formed using the film 1. [Example]

[0092] Examples of the present invention will be described below, but the present invention is not limited to these examples.

[0093] <Forming of film-like laminate> A three-layer laminate having a first outermost layer, an intermediate layer, and a second outermost layer was formed into a film by multilayer coextrusion T-die casting. In addition, each example 、 Comparative Example , and reference examples The raw materials for each layer were as follows: In addition, each example 、 Comparative Example , and reference examples The total thickness of the laminate was 80 μm in each case, and the thickness ratio of the layers was as shown in Tables 1 and 2.

[0094] [ Reference example A ] The components of each layer were as follows, and the blending amounts were as shown in Table 1. (1) First outermost layer Raw material A-1: ​​polyethylene resin composition (comonomer: ethylene-1-hexene copolymer) (product name: Evolue® SP0523A, manufactured by Prime Polymer Co., Ltd., density: 908 kg / m 3 , MFR: 2.0g / 10min) Raw material A-2: Modifier (ethylene-1-butene copolymer) (trade name: Tafmer (registered trademark) A-4070S / manufactured by Mitsui Chemicals, Inc., density: 870 kg / m 3 , MFR: 3.6g / 10min) Raw material A-3: Anti-blocking agent (silicon dioxide, 10 μm diameter) (2) Middle class Raw material B-1: Linear low-density polyethylene (comonomer: ethylene-1-hexene copolymer) (product name: Evolue® SP0510, manufactured by Prime Polymer Co., Ltd., density: 904 kg / m 3 , MFR: 1.2g / 10min) Raw material B-2: Modifier (ethylene-1-butene copolymer) (trade name: Tafmer (registered trademark) A-4070S / manufactured by Mitsui Chemicals, Inc., density: 870 kg / m 3 , MFR: 3.6g / 10min) (3) The second outermost layer Raw material C-1: Linear low-density polyethylene (comonomer: ethylene-1-hexene copolymer) (product name: Evolue® SP0510, manufactured by Prime Polymer Co., Ltd., density: 904 kg / m 3 , MFR: 1.2g / 10min) Raw material C-2: polyethylene resin composition (comonomer: ethylene-1-hexene copolymer) (trade name: Evolue® SP0523A, manufactured by Prime Polymer Co., Ltd., density: 908 kg / m 3 , MFR: 2.0g / 10min) Raw material C-3: Modifier (ethylene-1-butene copolymer) (trade name: Tafmer (registered trademark) A-4070S / manufactured by Mitsui Chemicals, Inc., density: 870 kg / m 3 , MFR: 3.6g / 10min) Raw material C-4: Anti-blocking agent (silicon dioxide, 10 μm diameter)

[0095] [ Reference example B ] Other than the components of the second outermost layer listed below, Reference example A The components were the same as those in the previous example. The blending amounts of the components in each layer were as shown in Table 1. (1) The second outermost layer Raw material C-1: polyethylene resin composition (comonomer: ethylene-1-hexene copolymer) (trade name: Evolue® SP0523A, manufactured by Prime Polymer Co., Ltd., density: 908 kg / m 3 , MFR: 2.0g / 10min) Raw material C-2: Modifier (ethylene-1-butene copolymer) (trade name: Tafmer (registered trademark) A-4070S / manufactured by Mitsui Chemicals, Inc., density: 870 kg / m 3 , MFR: 3.6g / 10min) Raw material C-3: Anti-blocking agent (silicon dioxide, 10 μm diameter)

[0096] [ Reference example C ] Other than the components of the first outermost layer and the second outermost layer described below, Reference example A The components were the same as those in the previous example. The blending amounts of the components in each layer were as shown in Table 1. (1) First outermost layer Raw material A-1: ​​polyethylene resin composition (comonomer: ethylene-1-hexene copolymer) (product name: Evolue® SP0523A, manufactured by Prime Polymer Co., Ltd., density: 908 kg / m 3 , MFR: 2.0g / 10min) Raw material A-2: Modifier (ethylene-1-butene copolymer) (trade name: Tafmer (registered trademark) A-4085S / manufactured by Mitsui Chemicals, Inc., density: 885 kg / m 3 , MFR: 3.6g / 10min) Raw material A-3: Anti-blocking agent (silicon dioxide, 10 μm diameter) (2) The second outermost layer Raw material C-1: Linear low-density polyethylene (comonomer: ethylene-1-hexene copolymer) (product name: Evolue® SP0510, manufactured by Prime Polymer Co., Ltd., density: 904 kg / m 3 , MFR: 1.2g / 10min) Raw material C-2: Modifier (ethylene-1-butene copolymer) (trade name: Tafmer (registered trademark) A-4085S / manufactured by Mitsui Chemicals, Inc., density: 885 kg / m 3 , MFR: 3.6g / 10min), Raw material C-3: Anti-blocking agent (silicon dioxide, 10 μm diameter)

[0097] [ Reference example D ] Except for changing the surface roughness of the first outermost layer, Reference example C The same was done as above. Reference example C and Reference example D The surface roughness of the first outermost layer in the test piece was measured as follows.

[0098] [Measurement of surface roughness (arithmetic mean roughness) Ra] The arithmetic mean roughness Ra of the surface of the first outermost layer of the obtained laminate (the surface opposite to the surface in contact with the intermediate layer) was measured using the following measuring device and under the following conditions. The results are shown in Table 3. Measurement device: Handysurf E-35A / B (manufactured by ACCRETECH Co., Ltd. 18-6-8589) Measurement conditions: Cutoff value: 0.8 μm

[0099] [ Reference example E ] The components of each layer were as follows, and the blending amounts were as shown in Table 1. (1) First outermost layer Raw material A-1: ​​polyethylene resin composition (comonomer: ethylene-1-hexene copolymer) (product name: Evolue® SP0523A, manufactured by Prime Polymer Co., Ltd., density: 908 kg / m 3 , MFR: 2.0g / 10min) Raw material A-2: Modifier (ethylene-1-octene copolymer) (trade name: Affinity® EG8100G, manufactured by Dow Chemical Company, density: 870 kg / m 3 , MFR: 1.0g / 10min) Raw material A-3: Anti-blocking agent (silicon dioxide, 10 μm diameter) (2) Middle class Raw material B-1: Linear low-density polyethylene (comonomer: ethylene-1-hexene copolymer) (product name: Evolue® SP0510, manufactured by Prime Polymer Co., Ltd., density: 904 kg / m 3 , MFR: 1.2g / 10min) Raw material B-2: Modifier (ethylene-1-octene copolymer) (trade name: Affinity® EG8100G, manufactured by Dow Chemical Company, density: 870 kg / m 3 , MFR: 1.0g / 10min) (3) The second outermost layer Raw material C-1: Linear low-density polyethylene (comonomer: ethylene-1-hexene copolymer) (product name: Evolue® SP0510, manufactured by Prime Polymer Co., Ltd., density: 904 kg / m 3 , MFR: 1.2g / 10min) Raw material C-2: polyethylene resin composition (comonomer: ethylene-1-hexene copolymer) (trade name: Evolue® SP0523A, manufactured by Prime Polymer Co., Ltd., density: 908 kg / m 3 , MFR: 2.0g / 10min) Raw material C-3: Modifier (ethylene-1-octene copolymer) (trade name: Affinity® EG8100G, manufactured by Dow Chemical Company, density: 870 kg / m 3 , MFR: 1.0g / 10min)

[0100] [Example 6] Other than the components of the second outermost layer listed below, Reference example E The components were the same as those in the previous example. The blending amounts of the components in each layer were as shown in Table 1. (1) The second outermost layer Raw material C-1: Linear low-density polyethylene (comonomer: ethylene-1-hexene copolymer) (product name: Evolue® SP0510, manufactured by Prime Polymer Co., Ltd., density: 904 kg / m 3 , MFR: 1.2g / 10min) Raw material C-2: polyethylene resin composition (comonomer: ethylene-1-hexene copolymer) (trade name: Evolue® SP0523A, manufactured by Prime Polymer Co., Ltd., density: 908 kg / m 3 , MFR: 2.0g / 10min) Raw material C-3: Modifier (styrene-ethylene / butylene-styrene copolymer) (product name: Kraton G-1657VS, manufactured by Kraton Polymer Japan Co., Ltd., density: 900 kg / m 3 )

[0101] [Example 7] Other than the components of the second outermost layer listed below, Reference example E The components were the same as those in the previous example. The blending amounts of the components in each layer were as shown in Table 1. (1) The second outermost layer Raw material C-1: Linear low-density polyethylene (comonomer: ethylene-1-hexene copolymer) (product name: Evolue® SP0510, manufactured by Prime Polymer Co., Ltd., density: 904 kg / m 3 , MFR: 1.2g / 10min) Raw material C-2: polyethylene resin composition (comonomer: ethylene-1-hexene copolymer) (trade name: Evolue® SP0523A, manufactured by Prime Polymer Co., Ltd., density: 908 kg / m 3 , MFR: 2.0g / 10min) Raw material C-3: Modifier (styrene-ethylene / butylene-styrene copolymer) (product name: TUFTEC (registered trademark) H1052 / manufactured by Asahi Kasei Corporation, density: 890 kg / m 3 , MFR: 13.0g / 10min)

[0102] [Example 8] The components other than those of the intermediate layer described below were the same as those in Example 7. The blending amounts of the components of each layer were as shown in Table 1. (1) Middle Class Linear low-density polyethylene (comonomer: ethylene-1-hexene copolymer) (trade name: Evolue® SP0510, manufactured by Prime Polymer Co., Ltd., density: 904 kg / m 3 , MFR: 1.2g / 10min) Raw material B-2: Modifier (styrene-ethylene / butylene-styrene copolymer) (product name: TUFTEC (registered trademark) H1052 / manufactured by Asahi Kasei Corporation, density: 890 kg / m 3 , MFR: 13.0g / 10min)

[0103] [Example 9] The intermediate layer was the same as in Example 8 except for the amounts of raw materials B-1 and B-2 blended.

[0104] [Example 10] The intermediate layer was the same as in Example 8 except for the amounts of raw materials B-1 and B-2 blended.

[0105] [Comparative Example 1] The components of each layer were as follows, and the blending amounts were as shown in Table 2. (1) First outermost layer Raw material A-1: ​​Linear low-density polyethylene (comonomer: ethylene-1-hexene copolymer) (product name: Evolue® SP1510, manufactured by Prime Polymer Co., Ltd., density: 915 kg / m 3 , MFR: 1.0g / 10min) Raw material A-2: Linear low-density polyethylene (comonomer: ethylene-1-hexene copolymer) (product name: Evolue® SP0510, manufactured by Prime Polymer Co., Ltd., density: 904 kg / m 3 , MFR: 1.2g / 10min) Raw material A-3: Modifier (ethylene-1-butene copolymer) (trade name: Tafmer (registered trademark) A-1085S, manufactured by Mitsui Chemicals, Inc., density: 885 kg / m 3 , MFR: 1.2g / 10min) Raw material A-4: Anti-blocking agent (silicon dioxide, 10 μm diameter) (2) Middle class Raw material B-1: Linear low-density polyethylene (comonomer: ethylene-1-hexene copolymer) (product name: Evolue® SP0510, manufactured by Prime Polymer Co., Ltd., density: 904 kg / m 3 , MFR: 1.2g / 10min) Raw material B-2: Modifier (ethylene-1-butene copolymer) (trade name: Tafmer (registered trademark) A-1085S / manufactured by Mitsui Chemicals, Inc., density: 885 kg / m 3 , MFR: 1.2g / 10min) (3) The second outermost layer Raw material C-1: Linear low-density polyethylene (comonomer: ethylene-1-hexene copolymer) (product name: Evolue® SP1510, manufactured by Prime Polymer Co., Ltd., density: 915 kg / m 3 , MFR: 1.0g / 10min) Raw material C-2: Linear low-density polyethylene (comonomer: ethylene-1-hexene copolymer) (product name: Evolue® SP0510, manufactured by Prime Polymer Co., Ltd., density: 904 kg / m 3 , MFR: 1.2g / 10min) Raw material C-3: Modifier (ethylene-1-butene copolymer) (trade name: Tafmer (registered trademark) A-1085S / manufactured by Mitsui Chemicals, Inc., density: 885 kg / m 3 , MFR: 1.2g / 10min) Raw material C-4: Anti-blocking agent (silicon dioxide, 10 μm diameter)

[0106] Comparative Example 2 The components of each layer were as follows, and the blending amounts were as shown in Table 2. (1) First outermost layer Raw material A-1: ​​Linear low-density polyethylene (comonomer: ethylene-1-hexene copolymer) (product name: Evolue® SP0510, manufactured by Prime Polymer Co., Ltd., density: 904 kg / m 3 , MFR: 1.2g / 10min) Raw material A-2: Modifier (ethylene-1-butene copolymer) (trade name: Tafmer (registered trademark) A-4070S / manufactured by Mitsui Chemicals, Inc., density: 870 kg / m 3 , MFR: 3.6g / 10min) Raw material A-3: Anti-blocking agent (silicon dioxide, 10 μm diameter) (2) Middle class Raw material B-1: Linear low-density polyethylene (comonomer: ethylene-1-hexene copolymer) (product name: Evolue® SP0510, manufactured by Prime Polymer Co., Ltd., density: 904 kg / m 3 , MFR: 1.2g / 10min) Raw material B-2: Modifier (ethylene-1-butene copolymer) (trade name: Tafmer (registered trademark) A-4070S / manufactured by Mitsui Chemicals, Inc., density: 870 kg / m 3 , MFR: 3.6g / 10min) (3) The second outermost layer Raw material C-1: Linear low-density polyethylene (comonomer: ethylene-1-hexene copolymer) (product name: Evolue® SP0510, manufactured by Prime Polymer Co., Ltd., density: 904 kg / m 3 , MFR: 1.2g / 10min) Raw material C-2: Modifier (ethylene-1-butene copolymer) (trade name: Tafmer (registered trademark) A-4070S / manufactured by Mitsui Chemicals, Inc., density: 870 kg / m 3 , MFR: 3.6g / 10min) Raw material C-3: Anti-blocking agent (silicon dioxide, 10 μm diameter)

[0107] Comparative Example 3 The same procedures as in Comparative Example 2 were followed except for the amounts of raw materials A-1 and A-2 in the first outermost layer and the amounts of raw materials C-1, C-2, and C-3 in the second outermost layer.

[0108] Comparative Example 4 The amounts of raw materials A-1 and A-2 in the first outermost layer, raw materials B-1 and B-2 in the intermediate layer, and raw materials C-1 and C-2 in the second outermost layer were the same as in Comparative Example 2.

[0109] <Various evaluations> Each Example 、 Comparative Example , and reference examples The laminates prepared in the above were subjected to the following evaluations. and reference examples The evaluation results of the above are shown in Table 1, and the evaluation results of the comparative example are shown in Table 2.

[0110] (Thermal adhesion strength) The laminate was cut into a rectangular test film measuring 10 cm x 5 cm. Two test films were overlapped, with the first outermost layer of one test film facing the second outermost layer of the other. The test films were then sandwiched between the seal bars of a heat seal tester (TP-701-B, manufactured by Tester Sangyo Co., Ltd.) heated to 38°C. A pressure load of 1.5 kgf was applied for 900 seconds to seal the two test films together. The bonded films were then released from the seal bars and allowed to stand at room temperature for 15 minutes to stabilize. Using a universal material testing machine (Tensilon), the peeled pieces were pulled at a rate of 300 mm / min, and shear peeling was performed. Measurements were taken within 30 minutes of test film preparation.

[0111] (Bending resistance) The laminate was cut into a rectangular test film measuring 21.0 cm (14.3 inches) x 29.7 cm (11.7 inches). This test film was then wound into a cylindrical shape 21.0 cm (14.3 inches) long. One end of the cylindrical film was then fixed to the outer periphery of the disk-shaped fixed head of a Gelbo Flex Tester (manufactured by Rigaku Kogyo Co., Ltd.), and the other end of the cylindrical film was fixed to the outer periphery of the disk-shaped movable head of the tester, which was spaced 17.8 cm (7.0 inches) from the fixed head. The movable head was then rotated 440° toward the fixed head along the axes of the two parallel, opposing heads, while approaching them by 8.8 cm (3.5 inches). It was then moved straight forward 6.4 cm (2.5 inches) without rotating, and these movements were then repeated in the opposite direction to return the movable head to its initial position. This complete bending test cycle was continuously repeated at a rate of 40 cycles per minute. The bending test was carried out within 20 days after the test film was made, with a total number of cycles of 5,000 ( Reference examples A~D and Comparative Examples 1 to 4), and a total number of cycles of 1,500 (Example 6 ~10 、 Comparative Examples 1 to 4 , and Reference Examples A to E The evaluation of the two items was carried out at -20°C. After that, the number of pinholes that appeared in the area of ​​17.8 cm (7.0 inches) x 29.7 cm (11.7 inches) of the tested film, excluding the area fixed to the outer periphery of the fixed head and the movable head, was counted (A4 size: 528.7 cm 2 The number of pinholes per square inch (81.9 square inches) was measured.

[0112] (loop stiffness) The laminate was cut into a rectangular test film measuring 1.5 cm x 18 cm. This test film was looped, and the loop stiffness was measured by measuring the stress when the apex of the loop was pressed a certain distance with an indenter using a loop stiffness tester (manufactured by Toyo Seiki Seisaku-sho, A222401101) according to the loop stiffness test method (film stiffness test method).

[0113] [Table 1]

[0114] [Table 2]

[0115] [Table 3]

[0116] As is clear from Tables 1 and 2, Examples 6 The laminates of 10 or less were excellent in flexibility and no blocking occurred.

[0117] Although the preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings, the present invention is not limited to these examples. It is clear that a person skilled in the art to which the present invention pertains can conceive of various modifications or alterations within the scope of the technical ideas described in the claims, and it is understood that these also naturally fall within the technical scope of the present invention. [Explanation of symbols]

[0118] 1...film, 10...first outermost layer, 20...intermediate layer, 30...second outermost layer, 50...laminated body, 100...packaging bag, 110...bag body, 111...first surface, 112...second surface, 121, 122...side seal portion, 130...bottom seal portion, 140...opening.

Claims

1. A laminate comprising: a first outermost layer, a second outermost layer, and an intermediate layer between the first outermost layer and the second outermost layer; at least one layer of the first outermost layer, the intermediate layer, and the second outermost layer is a film containing a polyethylene-based resin composition containing a linear ethylene-based copolymer (A) and a low-density polyethylene (B), and a modifier; The density of the linear ethylene copolymer (A) is 894 kg / m ３ More than 914kg / m ３ is as follows: The density of the low-density polyethylene (B) is 935 kg / m ３ is as follows: The laminate, wherein the modifier is a styrene-based elastomer.

2. the content of the polyethylene resin composition in the laminate is 5% by mass or more and less than 100% by mass; The laminate according to claim 1 .

3. The content of the modifier in the laminate is 0.5% by mass or more and 60% by mass or less. The laminate according to claim 2 .

4. the second outermost layer is the film; The laminate according to any one of claims 1 to 3.

5. The density of the linear ethylene copolymer (A) is 896 kg / m ３ More than 910kg / m ３ Below is the The laminate according to any one of claims 1 to 4.

6. The density of the low-density polyethylene (B) is 870 kg / m ３ More than 910kg / m ３ Below is the The laminate according to any one of claims 1 to 5.

7. a thermal adhesion strength between the first outermost layer and the second outermost layer is 0 to 1.2 kgf / 50 mm; The laminate according to any one of claims 1 to 6.

8. The number of pinholes generated in the laminate, measured using a Gelbo flex tester at −20° C. and 1,500 cycles, is 1.0 pinholes / A4 or less. The laminate according to any one of claims 1 to 7.

9. The loop rigidity of the laminate is 10 N / 15 mm or less. The laminate according to any one of claims 1 to 8.

10. Contains plant-derived resin, The laminate according to any one of claims 1 to 9.

11. the second outermost layer and the intermediate layer are the films; The laminate according to any one of claims 1 to 10.

12. the first outermost layer, the second outermost layer, and the intermediate layer are the films; The laminate according to any one of claims 1 to 11.

13. the first outermost layer comprises an antiblocking agent; The laminate according to any one of claims 1 to 12.

14. A packaging bag comprising the laminate according to any one of claims 1 to 13.

15. A bag-in-box comprising the packaging bag according to claim 14.

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