Laminate

Abstract

The purpose of the present invention is to provide a laminate which comprises a propylene polymer as a main component, has excellent low-temperature heat sealability and heat seal strength, and has a high peeling energy by controlling a peeling mode. The present invention relates to a sealant film having a heat-fusible layer and an adjacent layer adjacent to the heat-fusible layer, the sealant film being characterized in that the sealant film satisfies the following requirement (1), the heat-fusible layer includes an olefin-based polymer (B) satisfying the following requirement (2) and a propylene-based polymer (A) satisfying the following requirement (3), the adjacent layer comprises 1-70 mass% of the propylene-based polymer (A) satisfying the following requirement (3) and 30-99 mass% of the olefin-based polymer (B) satisfying the following requirement (2), and contains 0-70 mass% of a propylene polymer (B2) in the olefin-based polymer (B) (where, (A) + (B) = 100 mass%).　Requirement (1): the sealant film is a stretched film or a non-stretched film.　Requirement (2): melting point is less than 120 °C or not observed.　Requirement (3): melting point is 121 °C to 170 °C.

Description

Technical Field

[0001] The present invention relates to a laminate including a sealant film and a substrate, which contains a high content of a propylene-based polymer, is excellent in low-temperature heat sealability and heat seal strength, and has a high peel energy with a controlled peel mode.

Background Art

[0002] As films for heat seal packaging, crystalline polypropylene films such as biaxially stretched films (OPP films) and unstretched films (CPP films) made of crystalline polypropylene are widely used. Crystalline polypropylene films are excellent in rigidity, heat resistance, etc., but since the heat seal temperature is high, a sealant layer is usually laminated to improve the heat sealability.

[0003] As sealant films for packaging materials, films using a composition in which an ethylene-based copolymer is blended with a propylene-based copolymer or only an ethylene-based copolymer are widely used. For example, Patent Document 1 describes a laminate excellent in low-temperature heat sealability, including a sealant film containing a polypropylene resin, an ethylene·α-olefin random copolymer, and a 1-butene·α-olefin random copolymer.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] Ethylene copolymers are excellent in low-temperature sealing properties and heat-sealing strength. However, in view of recyclability from the perspective of environmental issues, it is preferable to be a single material as much as possible. For this reason, a sealant film and a laminate having a propylene copolymer as a main component and having sealant properties equal to or better than those of the above ethylene copolymer have been demanded.

[0006] Furthermore, in actual use, not only increasing the reaching point of heat-sealing strength but also increasing the peel energy, which means the total energy until peeling occurs, is considered to make peeling more difficult.

[0007] An object of the present invention is to provide a sealant film and a laminate excellent in peel energy by achieving high heat-sealing strength by providing an adjacent layer adjacent to a heat-sealing layer with a propylene polymer [in this specification, unless otherwise specified, "polymer" includes both homopolymers and copolymers.] as a main component and controlling the peeling behavior.

Means for Solving the Problems

[0008] The present invention relates to a sealant film having a heat-sealing layer and an adjacent layer adjacent to the heat-sealing layer, wherein the sealant film satisfies the following requirement (1). The heat-sealing layer contains an olefin polymer (B) satisfying the following requirement (2) and a propylene polymer (A) satisfying the following requirement (3). The adjacent layer is composed of 1 to 70% by mass of a propylene polymer (A) satisfying the following requirement (3) and 30 to 99% by mass of an olefin polymer (B) satisfying the following requirement (2), and contains 0 to 70% by mass of a propylene polymer (B2) in the olefin polymer (B) [however, (A)+(B)=100% by mass]. The present invention relates to a sealant film characterized by this.

[0009] Requirement (1): The sealant film is a stretched film or an unstretched film. Requirement (2): The melting point is less than 120°C or not observed. Requirement (3): The melting point is 121°C or higher and 170°C or lower.

Advantages of the Invention

[0010] The laminate of the present invention has a high content of a propylene-based polymer, achieves high heat seal strength, and has a controlled peel mode, thereby having a high peel energy.

Embodiments for Carrying Out the Invention

[0011] The sealant film of the present invention is a film including a heat-sealing layer and an adjacent layer. The laminate of the present invention includes a sealant film and a base film. The laminate of the present invention has a structure in which a sealant film and a base film are laminated. The sealant film is a film that imparts heat-sealability to the laminate of the present invention, and the base film is a film that supports the sealant film.

[0012] <Sealant Film> The sealant film of the present invention is a sealant film having a heat-sealing layer and an adjacent layer adjacent to the heat-sealing layer, and the sealant film satisfies the following requirement (1). The heat-sealing layer includes an olefin-based polymer (B) that satisfies the following requirement (2) and a propylene-based polymer (A) that satisfies the following requirement (3). The adjacent layer is composed of 1 to 70% by mass of a propylene-based polymer (A) that satisfies the following requirement (3) and 30 to 99% by mass of an olefin-based polymer (B) that satisfies the following requirement (2), and contains 0 to 70% by mass of a propylene polymer (B2) in the olefin-based polymer (B) [however, (A) + (B) = 100% by mass]. It is a sealant film characterized by this.

[0013] Requirement (1): The sealant film is a stretched film or an unstretched film. Requirement (2): The melting point is less than 120°C or not observed. Requirement (3): The melting point is 121°C or higher and 170°C or lower.

[0014] The sealant film of the present invention preferably has a heat seal strength (peel strength) of 6 N / 15 mm or more at 100°C when the heat-sealable layers are heat-sealed together, and high peel energy can be achieved by appropriately controlling the peel mode.

[0015] The methods for measuring the heat seal strength, peel energy, and determining the peel mode will be described in detail in the examples. The peel energy is determined as the area of the peel curve (S-S curve) during peeling. That is, the higher the heat seal strength and the longer the tensile distance (strain amount) from the start of peeling to the occurrence of breakage, the higher the peel energy can be.

[0016] In the sealant film according to the present invention, the heat seal strength at a temperature of 100°C, a pressure of 0.1 MPa, and a pressure application time of 0.5 seconds when the heat-sealable layers are adhered together is 6 N / 15 mm or more, preferably 8 N / 15 mm or more, more preferably 10 N / 15 mm or more. When the heat seal strength is 6 N / 15 mm or more, a laminate with high peel energy can be obtained.

[0017] In the sealant film according to the present invention, the peel mode is preferably cohesive failure. As a result, the tensile distance (strain amount) from the start of peeling to the occurrence of breakage becomes long, and a laminate with high peel energy can be obtained. Intermittent emission The peel energy at 110°C is preferably 20 mJ or more, more preferably 40 mJ or more, even more preferably 80 mJ or more, and particularly preferably 100 mJ. High peel energy can be achieved by having a high heat seal strength and / or the peel mode being cohesive failure.

[0018] 110°C is preferably 20 mJ or more, more preferably 40 mJ or more, even more preferably 80 mJ or more, and particularly preferably 100 mJ. High peel energy can be achieved by having a high heat seal strength and / or the peel mode being cohesive failure. Above High peel energy can be achieved by having a high heat seal strength and / or the peel mode being cohesive failure.

[0019] The sealant film of the present invention, for example, the total thickness of the heat-sealable layer and the adjacent layer WithIt can be obtained by setting it to 0.1 μm or more. The thickness of the sealant film of the present invention is usually 0.1 to 50 μm, preferably 0.3 to 40 μm, more preferably 0.5 to 25 μm, and particularly preferably 1 to 9 μm. When there are multiple sealant films, it is preferable that each sealant film has the above thickness.

[0020] Moreover, the thickness of the heat-sealing layer constituting the sealant film of the present invention is usually 0.1 to 20 μm. Looking at the lower limit side, it is preferably 0.2 μm, more preferably 0.3 μm, and particularly preferably 0.4 μm. Looking at the upper limit side, it is preferably 10 μm, more preferably 8 μm, and particularly preferably 5 μm.

[0021] Moreover, the thickness of the adjacent layer adjacent to the heat-sealing layer constituting the sealant film of the present invention is usually 0.1 to 30 μm. Looking at the lower limit side, it is preferably 0.2 μm, more preferably 0.4 μm, and particularly preferably 0.6 μm. Looking at the upper limit side, it is preferably 10 μm, more preferably 8 μm, and particularly preferably 6 μm.

[0022] The total thickness of the sealant film is usually 50% or less, preferably 40% or less, and more preferably 35% or less of the total thickness of the laminate combined with the base material layer described later. This makes the laminate approach a single material mainly composed of the base material layer, and has the advantage of facilitating recycling.

[0023] The sealant film of the present invention is preferably a stretched film or an unstretched film, and more preferably a stretched film. Moreover, the stretched film may be either a uniaxially stretched film or a biaxially stretched film, but a biaxially stretched film is particularly preferable because it has an excellent balance of longitudinal and transverse strength and rigidity.

[0024] The sealant film of the present invention is preferably a stretched film that has been stretched after being formed as a film. When the sealant film is a stretched film, it is possible to provide a laminate excellent in stiffness.

[0025] As a method for stretching the sealant film, known methods for manufacturing a stretched film can be used. Specifically, roll stretching, tenter stretching, tubular stretching, or a combination of these stretching methods can be mentioned. The stretching (surface) magnification is 1.5 to 50 times, preferably 2 to 40 times.

[0026] The sealant film of the present invention can contain additives such as other resins, tackifiers, weather stabilizers, heat stabilizers, antistatic agents, slip agents, antiblocking agents, lubricants, pigments, dyes, plasticizers, antioxidants, hydrochloric acid absorbers, and antioxidants as necessary within a range that does not impair the object of the present invention.

[0027] <<Heat-sealing layer>> The heat-sealing layer constituting the sealant film of the present invention is a layer containing an olefin polymer (B) that satisfies the above requirement (2) and a propylene polymer (A) that satisfies the above requirement (3).

[0028] The heat-sealing layer according to the present invention preferably contains 0.1 to 80% by mass of the olefin polymer (B). Looking at the lower limit side of the olefin polymer (B) here, it is more preferably 5% by mass, further preferably 8% by mass, and particularly preferably 10% by mass. Looking at the upper limit side, it is more preferably 64% by mass, further preferably 50% by mass, and particularly preferably 40% by mass. Content of Looking at the lower limit side, it is more preferably 5% by mass, further preferably 8% by mass, and particularly preferably 10% by mass. Looking at the upper limit side, it is more preferably 64% by mass, further preferably 50% by mass, and particularly preferably 40% by mass.

[0029] The heat-sealing layer according to the present invention preferably contains 20 to 99.9% by mass of the propylene polymer (A). Looking at the olefin polymer (B) here Content ofLooking at the lower limit side, it is more preferably 36% by mass, even more preferably 50% by mass, and particularly preferably 60% by mass. Looking at the upper limit side, it is more preferably 95% by mass, even more preferably 92% by mass, and particularly preferably 90% by mass [provided that the total amount of (A) + (B) is 100% by mass].

[0030] By containing the olefin polymer (B) within the above range, the heat-sealing layer according to the present invention has an excellent balance between low-temperature sealability and blocking property. When the proportion of the olefin polymer (B) is below the above range, the low-temperature sealability deteriorates, and when it exceeds the above range, the blocking property deteriorates.

[0031] 〈Olefin Polymer (B)〉 The olefin polymer (B) forming the heat-sealing layer according to the present invention Melting point is is not particularly limited as long as it is a polymer containing an olefin with a melting point of less than 120°C or not observable. When the melting point of the olefin polymer (B) according to the present invention is within the above range, a laminate excellent in low-temperature heat sealability can be obtained.

[0032] Examples of the olefin polymer (B) according to the present invention include homopolymers of α-olefins, copolymers of the α-olefins and other α-olefins, and copolymers of the α-olefins and monomers other than α-olefins.

[0033] The olefin polymer (B) according to the present invention is specifically an ethylene polymer mainly composed of ethylene such as a homopolymer of ethylene and a copolymer of ethylene and an α-olefin having 3 or more carbon atoms (ethylene·α-olefin copolymer) [hereinafter, in the present invention, it may be referred to as "ethylene polymer (B1)"]. A propylene-based polymer mainly composed of propylene such as a copolymer of propylene and ethylene and / or an α-olefin having 4 or more carbon atoms (propylene·α-olefin copolymer) [hereinafter, in the present invention, it may be referred to as "propylene polymer (B2)"]. A 1-butene-based polymer mainly composed of 1-butene such as a homopolymer of 1-butene and a copolymer of 1-butene and ethylene, propylene, and an α-olefin having 5 or more carbon atoms (1-butene·α-olefin copolymer) [hereinafter, it may be referred to as "butene polymer (B3)"]. And the like polymers can be mentioned.

[0034] When used for the heat-sealing layer, among these polymers, propylene polymer (B2) and butene polymer (B3) are more preferable, propylene polymer (B2) is even more preferable, and propylene·1-butene copolymer is particularly preferable.

[0035] In addition, propylene polymer (B2) and butene polymer (B3) have the characteristic that even if the melting point is low, it is difficult to deteriorate the film blocking property. 〈Ethylene polymer (B1)〉 In the ethylene polymer (B1) according to the present invention, examples of the α-olefin having 3 or more carbon atoms copolymerized with ethylene include α-olefins having 3 to 20 carbon atoms such as propylene, 1-butene, 1-pentene, 3-methyl-1-butene, 4-methyl-1-pentene, 1-hexene, 1-octene, 1-decene, 1-dodecene, and 1-tetradecene. 1-Butene, 1-hexene, and 1-octene are excellent in the balance of strength, flexibility, and low-temperature sealability improvement performance, and are preferable. The α-olefin copolymerized with ethylene is not limited to one kind, and may be two or more kinds of α-olefins.

[0036] Specific examples of the ethylene polymer (B1) according to the present invention include high-pressure low-density polyethylene, linear low-density polyethylene, and ethylene-α-olefin copolymers. 〈Propylene polymer (B2)〉 In the propylene polymer (B2) according to the present invention, examples of the α-olefin having 4 or more carbon atoms copolymerized with propylene include the above-mentioned α-olefins other than propylene. The α-olefin copolymerized with propylene is not limited to one kind, and may be two or more kinds of α-olefins (including ethylene). As the propylene polymer (B2), a propylene-ethylene copolymer, a propylene-1-butene copolymer, and a propylene-ethylene-1-butene copolymer are preferable. The propylene-ethylene copolymer and the propylene-1-butene copolymer are excellent in flexibility and can promote stress relaxation. The propylene-1-butene copolymer has high crystallinity even at a low melting point and is less likely to deteriorate the film blocking property.

[0037] 〈Butene polymer (B3)〉 In the butene polymer (B3) according to the present invention, examples of the α-olefin having 5 or more carbon atoms copolymerized with 1-butene include the above-mentioned α-olefins other than propylene and 1-butene. The α-olefin copolymerized with 1-butene is not limited to one kind, and may be two or more kinds of α-olefins (including ethylene and propylene). As the butene polymer (B3), a 1-butene-ethylene copolymer and a 1-butene-propylene copolymer are preferable. The 1-butene-ethylene copolymer and the 1-butene-propylene copolymer have a low melting point, excellent low-temperature heat sealability, and are less likely to deteriorate the film blocking property.

[0038] The olefin polymer (B) according to the present invention may be one kind of polymer or two or more kinds of polymers. The olefin polymer (B) according to the present invention preferably has an MFR measured under the conditions of 230 ° C. and a load of 2.16 kg in accordance with ASTM D1238 in the range of 0.1 to 100 g / 10 min, more preferably 1 to 20 g / 10 min.

[0039] In addition, the olefin polymer (B) according to the present invention preferably has an MFR measured under the conditions of 190°C and a load of 2.16 kg in accordance with ASTM D1238 in the range of 0.1 to 100 g / 10 min, more preferably 0.5 to 50 g / 10 min, and even more preferably 1 to 20 g / 10 min.

[0040] 〈Propylene polymer (A)〉 The propylene polymer (A) forming the heat-sealing layer according to the present invention is not particularly limited as long as its melting point is 121°C or higher and 170°C or lower, but examples include a homopolymer of propylene [also referred to as homopolymer PP: hPP], a random copolymer of propylene and other ethylene and / or With α-olefin having 4 or more carbon atoms a random copolymer [also referred to as random PP: rPP], and a block copolymer [also referred to as block PP: bPP].

[0041] The propylene polymer (A) according to the present invention preferably has an MFR measured under the conditions of 230°C and a load of 2.16 kg in accordance with ASTM D1238 in the range of 0.1 to 100 g / 10 min, more preferably 0.5 to 50 g / 10 min, and even more preferably 1 to 20 g / 10 min.

[0042] The heat-sealing layer according to the present invention contains the propylene polymer (A) and thus has excellent heat-sealing strength. The propylene polymer (A) according to the present invention can be produced by polymerizing a monomer in the presence of a known catalyst such as a Ziegler-Natta catalyst or a metallocene catalyst by a known polymerization method such as a gas phase method, a bulk method, or a slurry method. As a method for setting the melting point to 121°C or higher and 170°C or lower, for example, polymerization conditions such as the monomer feed amount are controlled And Polymerization with a Ziegler-Natta catalyst Do In the case of polymerization with a metallocene catalyst, the comonomer content is controlled to be less than 20 mol%, and in the case of polymerization with a metallocene catalyst Do a method of controlling the comonomer content to less than 10 mol% can be mentioned, and a polymer having a target melting point can be obtained by this method.

[0043] The olefin polymer (B) according to the present invention may be one type of polymer or two or more types of polymers. When used for the heat-sealing layer, as the propylene polymer (A), a random copolymer obtained by copolymerizing propylene with ethylene and / or an α-olefin having 4 or more carbon atoms is preferable. In order to improve the balance between blocking property and low-temperature sealability, it is preferable to copolymerize propylene with ethylene and an α-olefin having 4 or more carbon atoms, and a propylene-ethylene-1-butene copolymer is particularly preferable.

[0044] As the propylene polymer (A) used for the heat-sealing layer, the melting point is preferably 121 to 155°C, more preferably 130 to 145°C. 《Adjacent layer》 The adjacent layer constituting the sealant film of the present invention is a layer that relieves stress concentration during peeling after heat-sealing the heat-sealing layer.

[0045] The adjacent layer according to the present invention contains 1 to 70% by mass, preferably Is 3 to 50% by mass, more preferably 5 to 45% by mass of the propylene polymer (A), and 30 to 99% by mass, preferably 50 to 97% by mass, more preferably 55 to 95% by mass of the olefin polymer (B) that satisfies the above requirement (2). [However, (A)+(B)=100% by mass.]. Among the olefin polymers (B), the propylene polymer (B2) is contained in the range of 0 to 70% by mass, preferably 0 to 60% by mass, more preferably 1 to 40% by mass.

[0046] By containing the propylene polymer (A) and the like in the above range, the adjacent layer according to the present invention can improve the heat-sealing energy during peeling and improve the peeling appearance and peeling energy of the film.

[0047] 〈Propylene polymer (A)〉 The propylene-based polymer (A) for forming the adjacent layer according to the present invention is the same polymer as the propylene-based polymer (A) for forming the above heat-sealing layer. However, the propylene-based polymer (A) for forming the adjacent layer and the propylene-based polymer (A) for forming the heat-sealing layer may be polymers having the same physical properties or polymers having different physical properties.

[0048] As the propylene-based polymer (A) used for the adjacent layer, a propylene homopolymer and a random copolymer are preferable. The propylene homopolymer is excellent in strength and has a high melting point, so it is preferable in terms of preventing heat shrinkage of the laminate during heat sealing. The random copolymer is excellent in flexibility and is preferable in terms of promoting stress concentration.

[0049] 〈Olefin-based polymer (B)〉 The olefin-based polymer (B) for forming the adjacent layer according to the present invention is the same polymer as the olefin-based polymer (B) for forming the above heat-sealing layer. However, the olefin-based polymer (B) for forming the adjacent layer and the olefin-based polymer (B) for forming the heat-sealing layer may be polymers having the same physical properties or polymers having different physical properties.

[0050] As the olefin-based polymer (B) for forming the adjacent layer, it is preferable to include the propylene polymer (B2) as described above. By being compatible with the propylene-based polymer (A), the propylene polymer (B2) can improve flexibility while maintaining strength. As the propylene polymer (B2), a propylene-ethylene copolymer and a propylene-ethylene-α-olefin copolymer are preferable, a propylene-ethylene-α-olefin copolymer is more preferable, and a propylene-ethylene-1-butene copolymer is particularly preferable. Propylene Polymer (B2) is By containing ethylene, it is excellent in flexibility and can promote stress relaxation of the adjacent layer. Propylene polymer (B2) is By containing α-olefin, the compatibility between the propylene polymer (B2) and the propylene-based polymer (A) can be improved.

[0051] Propylene-ethylene-α-olefin copolymerThe body is and preferably, the content of the structural unit derived from propylene [hereinafter simply referred to as "propylene content"] is in the range of 40 to 99 mol%, more preferably 60 to 98 mol%, the ethylene content is 1 to 30 mol%, more preferably 1 to 20 mol%, and the α-olefin content is 1 to 30 mol%, more preferably 1 to 25 mol% (however, the total of the propylene content, ethylene content, and α-olefin content is 100 mol%). 。 By including the olefin polymer (B), the adjacent layer according to the present invention is excellent in heat seal strength, can control the peeling mode, and is excellent in peeling energy.

[0052] <Laminate> The laminate of the present invention is formed by laminating the adjacent layer that forms the sealant film of the present invention and the following base material film.

[0053] <<Base Material Film>> The base material film constituting the laminate of the present invention is at least one selected from a biaxially stretched polypropylene film and an unstretched polypropylene film.

[0054] The base material film according to the present invention usually has a thickness in the range of 10 to 200 μm, preferably 11 to 100 μm, more preferably 12 to 50 μm, and particularly preferably 12 to 19 μm. The base material film according to the present invention is preferably a biaxially stretched polypropylene film.

[0055] Among the laminates, it is preferable that the base material film is thicker than the sealant layer (sealant film) composed of the heat-sealing layer and the adjacent layer adjacent to the heat-sealing layer. This has the advantage that the laminate approaches a single material and recycling becomes easier. The thickness of the base material film is usually 50% or more, preferably 60% or more, more preferably 65% or more, and particularly preferably 68% or more of the entire laminate.

[0056] Further, when the thickness of the base film is x and the thickness of the adjacent layer is y, it is preferable that x > y for the thicknesses of the base film and the adjacent layer. Thereby, the rigidity of the obtained laminate is further improved.

[0057] 〈Polypropylene〉 Examples of the polypropylene constituting the polypropylene film forming the base film according to the present invention include a homopolymer of propylene and a copolymer having propylene as a main monomer. In the case of a copolymer, it may be a random copolymer or a block copolymer. Examples of the monomer copolymerized with propylene include α-olefins other than propylene and diene compounds. The propylene content (structural unit derived from propylene) in the polypropylene is 85 to 100 mol%, preferably 90 to 99.5 mol%, and the content of other monomers is 0 to 15 mol%, preferably 0.5 to 10 mol%.

[0058] Examples of other α-olefins copolymerized with propylene include α-olefins having 2 or 4 to 20 carbon atoms such as ethylene, 1-butene, 1-pentene, 3-methyl-1-butene, 4-methyl-1-pentene, 1-hexene, 1-octene, 1-decene, 1-dodecene, and 1-tetradecene.

[0059] The polypropylene according to the present invention preferably has an MFR measured under the conditions of 230°C and a load of 2.16 kg in accordance with ASTM D1238 of 0.1 to 10 g / 10 min, more preferably 0.5 to 8 g / 10 min, and a melting point (Tm) of preferably 120 to 165°C, more preferably 135 to 150°C.

[0060] Specific examples of the polypropylene according to the present invention include a propylene homopolymer, a propylene-ethylene random copolymer, a propylene-1-butene random copolymer, a propylene-1-butene-ethylene random copolymer, a propylene-1-hexene random copolymer, a propylene-3-methyl-1-butene random copolymer, and a propylene-4-methyl-1-pentene random copolymer. The polypropylene may be used alone or in combination of two or more.

[0061] The polypropylene according to the present invention can be produced by polymerizing a monomer in the presence of a known catalyst such as a Ziegler-Natta catalyst or a metallocene catalyst by a known polymerization method such as a gas phase method, a bulk method, or a slurry method.

[0062] The polypropylene according to the present invention may be the same polymer as the propylene-based polymer (A) and / or the propylene-α-olefin polymer (B2) contained in the sealant film.

[0063] The base film is at least one selected from an unstretched polypropylene film (CPP film) which is a film formed from the polypropylene and has not been subjected to a stretching treatment, and a biaxially stretched polypropylene film (OPP film) obtained by subjecting to a biaxial stretching treatment. As the stretching method, a known method for producing a stretched film can be used. Specifically, roll stretching, tenter stretching, tubular stretching, or a combination of these stretching methods can be mentioned. The stretching (plane) magnification is usually 1.5 to 50 times, preferably 2 to 40 times.

[0064] The base film according to the present invention may be composed of one layer or may be composed of a plurality of layers. The base film according to the present invention may contain additives such as other resins, tackifiers, weather stabilizers, heat stabilizers, antistatic agents, slip agents, antiblocking agents, lubricants, pigments, dyes, plasticizers, anti-aging agents, hydrochloric acid absorbers, and antioxidants.

[0065] When the total mass of the sealant film and the base film of the laminate of the present invention is 100% by mass, it contains 70% by mass or more of a propylene polymer and / or a 1-butene polymer. That is, when the total mass of the sealant film and the base film of the laminate of the present invention is 100% by mass, the propylene polymer is preferably contained in an amount of 50% by mass, more preferably 60% by mass or more, still more preferably 65% by mass or more, and particularly preferably 80% by mass or more. As a result, the laminate approaches a single material, and there is an advantage that recycling becomes easy.

[0066] Examples of the propylene polymer according to the present invention include a homopolymer of propylene, a copolymer of propylene and ethylene or an α-olefin having 4 to 20 carbon atoms, and the like. Examples of the α-olefin having 4 to 20 carbon atoms include 1-butene, 1-pentene, 3-methyl-1-butene, 4-methyl-1-pentene, 1-hexene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene and the like.

[0067] Examples of the 1-butene polymer according to the present invention include a homopolymer of 1-butene, a copolymer of 1-butene and ethylene, propylene or an α-olefin having 5 to 20 carbon atoms, and the like. Examples of the α-olefin having 5 to 20 carbon atoms include 1-pentene, 3-methyl-1-butene, 4-methyl-1-pentene, 1-hexene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene and the like.

[0068] The propylene polymer and the 1-butene polymer according to the present invention may both be the same as the propylene polymer (B2) and the butene polymer (B3) contained as the olefin polymer (B) in the sealant film of the present invention, may be the same as the polymer contained as polypropylene in the base film, or may be a polymer contained in a film other than the sealant film and the base film.

[0069] In order to impart specific functions to the laminate of the present invention, various layers can be included in addition to the sealant film and the base film of the present invention. For example, the laminate of the present invention can include functional material layers such as a printing layer, a barrier layer, and an embossing layer.

[0070] In addition, examples of the functional material layer include a resin film vapor-deposited with an inorganic compound or inorganic oxide, a metal foil, a coating film of a resin having a special function, and a resin film printed with a pattern. Here, as the resin film to be used, it is possible to use a resin film similar to the polypropylene film used for the base film. Furthermore, similar plastic compounding agents and additives can be added in any amount according to the purpose as long as they do not adversely affect other performances.

[0071] The resin film according to the present invention uses, for example, one or more resins selected from the group of resins similar to the resin for the base film, and is produced by a film-forming method conventionally used such as an extrusion method, a casting method, a T-die method, a cutting method, an inflation method, etc., or by a multi-layer co-extrusion film-forming method using two or more resins. Furthermore, from the viewpoints of film strength, dimensional stability, and heat resistance, for example, it can be stretched in a uniaxial or biaxial direction using a tenter method or a tubular method.

[0072] When the laminate of the present invention includes a barrier layer, it can be produced by a method for producing a laminate including a step of forming the barrier layer as one layer in the sealant film or the base film by metal vapor deposition, a coating method, or a co-extrusion method and a step of laminating the sealant film and the base film.

[0073] Examples of the aspect of the laminate of the present invention include, but are not limited to, a two-layer structure of a sealant film / base film and a three-layer structure of a sealant film / base film / sealant film. An adhesive layer can also be provided between the sealant film and the base film.

[0074] The sealant film and the base film may be laminated by coextrusion, or may be laminated by common lamination methods such as extrusion lamination or dry lamination. After coextruding the sealant film and the base film, the base film may be further laminated.

[0075] The laminate of the present invention may be manufactured by laminating a sealant film and a base film via an adhesive layer by dry lamination, non-solvent lamination, sand lamination, etc., or may be manufactured by laminating a sealant film and a base film by melt extrusion lamination. Among them, a method of laminating by dry lamination or melt extrusion lamination is preferable.

[0076] The laminate manufactured by the above method can be stretched. As the stretching method, a known method for manufacturing a stretched film can be used. Specifically, roll stretching, tenter stretching, tubular stretching, or a combination of these stretching methods can be mentioned. The stretching (surface) magnification is 1.5 to 50 times, preferably 2 to 40 times.

[0077] As described above, the laminate of the present invention has a high content of the propylene-based copolymer, and further has excellent low-temperature heat sealability and low-temperature Hi heat seal strength, the peel mode is controlled, and the peel energy is high.

[0078] A package can be obtained from the laminate of the present invention. The package formed by the laminate of the present invention has excellent low-temperature heat sealability and is difficult to break. For example, the heat-sealing layers of the sealant films of the laminate of the present invention are faced to each other, or the heat-sealing layer of the sealant film of the laminate film is faced to another film, and then at least a part of the periphery thereof is heat-sealed from the outer surface side so as to have a desired container shape, whereby a container can be manufactured. Further, by heat-sealing the entire periphery, a sealed bag-like container can be manufactured. When the forming process of this bag-like container is combined with the filling process of the content, that is, after heat-sealing the bottom and side portions of the bag-like container, the content is filled, and then the upper portion is heat-sealed, a package can be manufactured. This package can be used for an automatic packaging apparatus for solid substances such as snack foods and bread, powders, or liquid materials.

[0079] Further, the container obtained by previously forming the laminate of the present invention into a cup shape by vacuum forming, pressure-air forming, etc., the container obtained by injection molding, etc., or the container formed from a paper base material is filled with the content, and then the laminate of the present invention is coated as a lid material, and the upper or side portion of the container is heat-sealed, whereby a container in which the content is packaged can be obtained. This container is suitably used for packaging instant noodles, miso, jelly, pudding, snack foods, etc.

[0080] Recycled products of the laminate of the present invention or the package made of the laminate of the present invention can also be effectively utilized. The molded body which is a recycled product of the laminate or package of the present invention enables reduction of the amount of newly polymerized plastic used, and becomes an article that can contribute to reduction of the environmental load.

Examples

[0081] Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these Actual examples. In addition, each physical property measurement shown in this example was carried out by the following method.

[0082] [Heat-sealing strength] The heat-sealing layer surfaces of the sealant films of the two-layer laminate were overlapped, or the two single-layer films were overlapped, and heat-sealed at 90 °C, 100 °C, 110 °C or 120 °C under a pressure of 0.1 MPa for 0.5 seconds with a seal bar width of 5 mm, and then allowed to cool. Next, test pieces with a width of 15 mm were cut from each of the test specimens obtained by heat-sealing, and for each test piece, the peel strength when peeling the heat-sealed portion at a crosshead speed of 300 mm / min was measured, and the numerical value was taken as the heat-sealing strength.

[0083] [Peel Appearance] After peeling the heat-sealed portion, the sample peel morphology was confirmed, and the occurrence of cohesive peeling, film breakage, and film tearing was confirmed.

[0084] Those that peeled only at the interface were designated as "Peel", those in which the edge of the welded surface was broken were designated as "Tear", and those in which "Peel" and "Tear" were mixed were designated as "△". [Peel Energy] Based on Kazuo Hishinuma, "Proposal of a Method for Measuring and Evaluating the Peel Energy on the Welded Surface of Heat Welding (Heat Seal)", Journal of the Japan Welding Society, 2006, Vol. 42, No. 4, P. 146-152., the peel energy S was calculated by the following formula.

[0085] [Equation] S: Peel energy (mJ) F: Tensile strength (N) at each peel distance point Δl: Unit distance (mm) for energy calculation Lt: Tensile distance (mm) at the occurrence of breakage In the examples and comparative examples, the following polymers were used.

[0086] [Heat-sealing layer] [Propylene-based polymer (A)] As the propylene-based polymer (A), terPP: propylene terpolymer (A-1) was used.

[0087] MFR (at 230°C, 2.16 kg load, in accordance with ASTM D1238): 5.5 g / 10 min, melting point: 132°C, propylene content: 92 mol%, ethylene content: 3 mol%, 1-butene content: 5 mol%.

[0088] <Olefin polymer (B)> As the olefin polymer (B), PER (B2-1): a propylene-ethylene copolymer was used.

[0089] MFR (at 230°C, 2.16 kg load, in accordance with ASTM D1238): 3 g / 10 min, MFR (at 190°C, 2.16 kg load, in accordance with ASTM D1238): 1.4 g / 10 min, melting point: 108°C, propylene content: 78 mol%, ethylene content: 22 mol%.

[0090] <Adjacent layer> 〈Propylene polymer (A)〉 As the propylene polymer (A), hPP (A-2): a homopolypropylene (propylene homopolymer) was used.

[0091] MFR (at 230°C, 2.16 kg load, in accordance with ASTM D1238): 3.0 g / 10 min, melting point: 161°C. 〈Olefin polymer (B)〉 As the olefin polymer (B), the following HP-LDPE (B1-1), L-LDPE (B1-2), EBR (B1-3), EBR (B1-4) and EBR (B1-5) were used.

[0092] 〈HP-LDPE (B1-1)〉 High-pressure low-density polyethylene (Mirasun (registered trademark) F9673P manufactured by Mitsui Dow Polychemical Co., Ltd.) was used.

[0093] MFR (at 190°C, 2.16 kg load, in accordance with ASTM D1238): 1.1 g / 10 min, density: 918 kg / m 3 , melting point 108°C. 〈L-LDPE (B1-2)〉 Linear low density polyethylene (Evolue (registered trademark) SP0510 manufactured by Prime Polymer Co., Ltd.) was used.

[0094] MFR (at 190 °C, 2.16 kg load, in accordance with ASTM D1238): 1.2 g / 10 min, density (in accordance with JIS K7112): 903 kg / m 3 , melting point 98 °C. 〈EBR (B1-3)〉 Ethylene-1-butene copolymer (Tafmer (registered trademark) A-0585N manufactured by Mitsui Chemicals, Inc.) MFR (at 190 °C, 2.16 kg load, in accordance with ASTM D1238): 0.5 g / 10 min, density (in accordance with ASTM D1505): 885 kg / m3, melting point 66 °C.

[0095] 〈EBR (B1-4)〉 Ethylene-1-butene copolymer (Tafmer (registered trademark) A-1085S manufactured by Mitsui Chemicals, Inc.) MFR (at 190 °C, 2.16 kg load, in accordance with ASTM D1238): 1.2 g / 10 min, density (in accordance with ASTM D1505): 885 kg / m 3 , melting point 66 °C.

[0096] 〈EBR (B1-5)〉 Ethylene-1-butene copolymer (Tafmer (registered trademark) A-4085S manufactured by Mitsui Chemicals, Inc.) MFR (at 190 °C, 2.16 kg load, in accordance with ASTM D1238): 3.6 g / 10 min, density (in accordance with ASTM D1505): 885 kg / m 3 , melting point 66 °C.

[0097] 〈Propylene polymer (B2)〉 As the propylene polymer (B2), a propylene-ethylene-1-butene copolymer (hereinafter referred to as "PEBR (B2-2)") having an ethylene content of 14 mol%, a propylene content of 67 mol%, and a 1-butene content of 19 mol%, which was prepared according to the method described in the Example column of <the third invention> described in WO2006 / 57361 pamphlet, and whose melting point (Tm) measured by the usual method was not observed and MFR (230 ° C., 2.16 kg load, in accordance with ASTM D1238) was 6 g / 10 min was used.

[0098] 85% by mass of PEBR (B2-2) and 15% by mass of a propylene homopolymer (A-3) having a melting point (Tm) measured by the re-heating method of 160 ° C. and MFR (230 ° C., 2.16 kg load, in accordance with ASTM D1238) of 7 g / 10 min were kneaded and used as a pelletized propylene-based resin composition (B2-3).

[0099] 〈PER (B2-4)〉 Propylene-ethylene copolymer (VISTAMAXX (registered trademark) 6102 manufactured by ExxonMobil Chemical Company) MFR (230 ° C., 2.16 kg load, in accordance with ASTM D1238): 3 g / 10 min, melting point 108 ° C.

[0100] <Base film> The above hPP (A-2) was used. [Example 1] 30% by mass of PBR (B2-1) and 70% by mass of terPP (A-1) were blended to prepare a composition for producing a heat-sealing layer.

[0101] 40% by mass of hPP (A-2) and 60% by mass of HP-LDPE (B1-1) were blended to prepare a composition for producing an adjacent layer. Using three extruders connected with a T-die, the composition for producing the heat-sealing layer, the composition for producing the adjacent layer, and hPP (A-2) corresponding to the base film were co-extruded to obtain an unstretched laminated film in which a sealant film composed of a heat-sealing layer and an adjacent layer and a base film made of hPP (A-2) were laminated in the order of sealant film (heat-sealing layer / adjacent layer) / base film.

[0102] The obtained unstretched laminated film was biaxially stretched (stress relaxation for 30 seconds after stretching) at a stretching temperature of 158 °C and a stretching rate of 238% by a batch-type biaxial stretching machine to a longitudinal × transverse ratio of 5 times × 8 times, producing a laminate in which a sealant film consisting of a 3-μm-thick heat-sealing layer and a 3-μm-thick adjacent layer and a 14-μm-thick base film were biaxially stretched.

[0103] The physical property evaluation results of the obtained laminate are shown in Table 1. [Example 2] A laminate was obtained in the same manner as in Example 1, except that a composition for producing an adjacent layer was prepared by blending 40% by mass of hPP (A-2) and 60% by mass of L-LDPE (B1-2). The physical property evaluation results of the obtained laminate are shown in Table 1.

[0104] [Example 3] A laminate was obtained in the same manner as in Example 1, except that a composition for producing an adjacent layer was prepared by blending 30% by mass of hPP (A-2), 60% by mass of L-LDPE (B1-2), and 10% by mass of a propylene-based resin composition (B2-3). The physical property evaluation results of the obtained laminate are shown in Table 1.

[0105] [Example 4] A laminate was obtained in the same manner as in Example 1, except that a composition for producing an adjacent layer was prepared by blending 20% by mass of hPP (A-2), 60% by mass of L-LDPE (B1-2), and 20% by mass %, of a propylene-based resin composition (B2-3). The physical property evaluation results of the obtained laminate are shown in Table 1.

[0106] [Example 5] A laminate was obtained in the same manner as in Example 1, except that a composition for producing an adjacent layer was prepared by blending 10% by mass of hPP (A-2), 60% by mass of L-LDPE (B1-2), and 30% by mass of a propylene-based resin composition (B2-3). The physical property evaluation results of the obtained laminate are shown in Table 1.

[0107] [Example 6] A laminate was obtained in the same manner as in Example 1, except that a composition for producing an adjacent layer was prepared by blending 20% by mass of hPP (A-2), 60% by mass of EBR (B1-3), and 20% by mass of a propylene-based resin composition (B2-3). The physical property evaluation results of the obtained laminate are shown in Table 1.

[0108] [Example 7] A laminate was obtained in the same manner as in Example 1, except that a composition for producing an adjacent layer was prepared by blending 80% by mass of EBR (B1-3) and 20% by mass of a propylene-based resin composition (B2-3). The physical property evaluation results of the obtained laminate are shown in Table 1.

[0109] [Example 8] A laminate was obtained in the same manner as in Example 1, except that a composition for producing an adjacent layer was prepared by blending 40% by mass of hPP (A-2) and 60% by mass of EBR (B1-4). The physical property evaluation results of the obtained laminate are shown in Table 1.

[0110] [Example 9] A laminate was obtained in the same manner as in Example 1, except that a composition for producing an adjacent layer was prepared by blending 20% by mass of hPP (A-2), 60% by mass of EBR (B1-4), and 20% by mass of a propylene-based resin composition (B2-3). The physical property evaluation results of the obtained laminate are shown in Table 2.

[0111] [Example 10] A laminate was obtained in the same manner as in Example 1, except that a composition for producing an adjacent layer was prepared by blending 60% by mass of EBR (B1-4) and 40% by mass of a propylene-based resin composition (B2-3). The physical property evaluation results of the obtained laminate are shown in Table 2.

[0112] [Example 11] A laminate was obtained in the same manner as in Example 1, except that a composition for preparing an adjacent layer was prepared by blending 40% by mass of hPP (A-2), 40% by mass of EBR (B1-4), and 20% by mass of a propylene-based resin composition (B2-3). The results of physical property evaluation of the obtained laminate are shown in Table 2.

[0113] [Example 12] A laminate was obtained in the same manner as in Example 1, except that a composition for preparing an adjacent layer was prepared by blending 20% by mass of hPP (A-2), 40% by mass of EBR (B1-4), and 40% by mass of a propylene-based resin composition (B2-3). The results of physical property evaluation of the obtained laminate are shown in Table 2.

[0114] [Example 13] A laminate was obtained in the same manner as in Example 1, except that a composition for preparing an adjacent layer was prepared by blending 40% by mass of EBR (B1-4) and 60% by mass of a propylene-based resin composition (B2-3). The results of physical property evaluation of the obtained laminate are shown in Table 2.

[0115] [Example 14] A laminate was obtained in the same manner as in Example 1, except that a composition for preparing an adjacent layer was prepared by blending 80% by mass of EBR (B1-4) and 20% by mass of a propylene-based resin composition (B2-3). The results of physical property evaluation of the obtained laminate are shown in Table 2.

[0116] [Example 15] A laminate was obtained in the same manner as in Example 1, except that a composition for preparing an adjacent layer was prepared by blending 60% by mass of EBR (B1-5) and 40% by mass of hPP (A-2). The results of physical property evaluation of the obtained laminate are shown in Table 2.

[0117] [Example 16] A laminate was obtained in the same manner as in Example 1, except that a composition for preparing an adjacent layer was prepared by blending 20% by mass of hPP (A-2), 60% by mass of EBR (B1-5), and 20% by mass of a propylene-based resin composition (B2-3). The results of physical property evaluation of the obtained laminate are shown in Table 2.

[0118] [Example 17] A laminate was obtained in the same manner as in Example 1, except that a composition for producing an adjacent layer was prepared by blending 80% by mass of EBR (B1-5) and 20% by mass of a propylene-based resin composition (B2-3). The results of physical property evaluation of the obtained laminate are shown in Table 3.

[0119] [Example 18] A laminate was obtained in the same manner as in Example 1, except that a composition for producing an adjacent layer was prepared by blending 40% by mass of hPP (A-2), 40% by mass of EBR (B1-5), and 20% by mass of a propylene-based resin composition (B2-3). The results of physical property evaluation of the obtained laminate are shown in Table 3.

[0120] [Example 19] A laminate was obtained in the same manner as in Example 1, except that a composition for producing an adjacent layer was prepared by blending 40% by mass of hPP (A-2), 48% by mass of EBR (B1-4), and 12% by mass of PER (B2-4). The results of physical property evaluation of the obtained laminate are shown in Table 3.

[0121] [Example 20] An unstretched laminated film was obtained in the same manner as in Example 9. The obtained unstretched laminated film was biaxially stretched at a stretching temperature of 158 °C and a stretching rate of 238% to a biaxial stretching ratio of longitudinal × transverse = 5 times × 8 times (stress relaxation after stretching for 30 seconds) using a batch-type biaxial stretching machine to produce a laminate in which a sealant film composed of two layers, a heat-sealing layer with a thickness of 1 μm and an adjacent layer with a thickness of 3 μm, and a base film with a thickness of 14 μm were biaxially stretched.

[0122] The results of physical property evaluation of the obtained laminate are shown in Table 3. [Example 21] An unstretched laminated film was obtained in the same manner as in Example 9.

[0123] The obtained unstretched laminated film was biaxially stretched by a batch-type biaxial stretching machine at a stretching temperature of 158°C and a stretching speed of 238% to a biaxial stretch ratio of longitudinal × transverse = 5 times × 8 times (stress relaxation for 30 seconds after stretching) to produce a laminate in which a sealant film composed of two layers, a heat-sealing layer with a thickness of 0.5 μm and an adjacent layer with a thickness of 3 μm, and a base film with a thickness of 14 μm were biaxially stretched.

[0124] The physical property evaluation results of the obtained laminate are shown in Table 3. [Example 22] An unstretched laminated film was obtained in the same manner as in Example 9.

[0125] The obtained unstretched laminated film was biaxially stretched by a batch-type biaxial stretching machine at a stretching temperature of 158°C and a stretching speed of 238% to a biaxial stretch ratio of longitudinal × transverse = 5 times × 8 times (stress relaxation for 30 seconds after stretching) to produce a laminate in which a sealant film composed of two layers, a heat-sealing layer with a thickness of 3 μm and an adjacent layer with a thickness of 2 μm, and a base film with a thickness of 14 μm were biaxially stretched.

[0126] The physical property evaluation results of the obtained laminate are shown in Table 3. [Example 23] An unstretched laminated film was obtained in the same manner as in Example 9.

[0127] The obtained unstretched laminated film was biaxially stretched by a batch-type biaxial stretching machine at a stretching temperature of 158°C and a stretching speed of 238% to a biaxial stretch ratio of longitudinal × transverse = 5 times × 8 times (stress relaxation for 30 seconds after stretching) to produce a laminate in which a sealant film composed of two layers, a heat-sealing layer with a thickness of 3 μm and an adjacent layer with a thickness of 1 μm, and a base film with a thickness of 14 μm were biaxially stretched.

[0128] The physical property evaluation results of the obtained laminate are shown in Table 3. [Example 24] An unstretched laminated film was obtained in the same manner as in Example 9.

[0129] The obtained unstretched laminated film was biaxially stretched by a batch-type biaxial stretching machine at a stretching temperature of 158°C and a stretching rate of 238% to a biaxial stretch ratio of longitudinal × transverse = 5 times × 8 times (stress relaxation for 30 seconds after stretching) to produce a laminate in which a sealant film composed of two layers, a heat-sealing layer with a thickness of 1 μm and an adjacent layer with a thickness of 5 μm, and a base film with a thickness of 14 μm were biaxially stretched.

[0130] The physical property evaluation results of the obtained laminate are shown in Table 3. [Comparative Example 1] A laminate was obtained in the same manner as in Example 1, except that 100% by mass of hPP (A-2) was used in the adjacent layer. The physical property evaluation results of the obtained laminate are shown in Table 3.

[0131]

Table 1

[0132]

Table 2

[0133]

Table 3

Claims

1. A sealant film having a heat-sealing layer and an adjacent layer adjacent to the heat-sealing layer, wherein the sealant film satisfies the following requirement (1): The heat-sealing layer contains an olefin polymer (B) that satisfies the following requirement (2) and a propylene polymer (A) that satisfies the following requirement (3): The adjacent layer is composed of 1 to 70% by mass of a propylene polymer (A) that satisfies the following requirement (3) and 30 to 99% by mass of an olefin polymer (B) that satisfies the following requirement (2), and contains 0 to 70% by mass of a propylene polymer (B2) in the olefin polymer (B) [however, (A) + (B) = 100% by mass]. A sealant film in which the olefin polymer (B) in the heat-sealing layer is a propylene polymer (B2). Requirement (1): The sealant film is a stretched film or an unstretched film. Requirement (2): The melting point is less than 120°C or not observed. Requirement (3): The melting point is 121°C or higher and 170°C or lower.

2. The sealant film according to claim 1, wherein the olefin polymer (B) in the adjacent layer contains at least one olefin polymer selected from the group consisting of an ethylene polymer (B1), a propylene polymer (B2), and a 1-butene polymer (B3).

3. The sealant film according to claim 2, wherein the ethylene polymer (B1) is at least one selected from high-pressure low-density polyethylene, linear low-density polyethylene, and an ethylene / α-olefin copolymer.

4. The heat-sealing layer contains 0.1 to 80% by mass of an olefin polymer (B) and 20 to 99.9% by mass of a propylene polymer (A) [however, the total amount of (A) + (B) is 100% by mass]. The sealant film according to any one of claims 1 to 3.

5. The sealant film according to any one of claims 1 to 4, wherein the heat-sealing strength at 100°C when the heat-sealing layers are adhered to each other is 6 N / 15 mm or more.

6. A laminate having a base film adjacent to the adjacent layer of the sealant film according to any one of claims 1 to 5.

7. The laminate according to claim 6, wherein at least one film selected from the sealant film and the base film contains at least one layer selected from a printing layer, a barrier layer, and an embossing layer.

8. A package formed by the laminate according to claim 6 or 7. Claim 9 A method for manufacturing a laminate according to claim 6 or 7, wherein at least one film selected from the sealant film and the base material film contains a barrier layer, the method comprising the steps of forming the barrier layer as one layer in the sealant film or the base material film by metal vapor deposition, coating, or coextrusion, and laminating the sealant film and the base material film. Claim 10 A laminate comprising a heat-sealing layer containing a propylene polymer (B2) having a melting point of less than 120°C or not observable and an adjacent layer formed on one surface of the heat-sealing layer, wherein the adjacent layer consists of 1 to 70% by mass of a propylene-based polymer (A) satisfying the following requirement (3) and 30 to 99% by mass of an olefin-based polymer (B) satisfying the following requirement (2), the heat-sealing strength at 100°C when the heat-sealing layers are heat-sealed to each other under the conditions of temperature: 100°C, pressure: 0.1 MPa, and pressure application time: 0.5 seconds is 6 N / 15 mm or more, the peeling mode is cohesive peeling, and the laminate contains 50% by mass or more of the propylene polymer. Requirement (2): The melting point is less than 120°C or not observable. Requirement (3): The melting point is 121°C or higher and 170°C or lower.

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