JP2021070250A - Laminate - Google Patents

Abstract

SOLUTION: A laminate is provided, comprising a sealant film satisfying the following requirements (1) to (3) and a substrate film satisfying requirement (4), and containing a propylene (co)polymer and/or 1-butene (co)polymer by 70 mass% or more when the total mass of the sealant film and the substrate film is set to 100 mass%. The requirements are: (1) the sealant film has at least a hot-melt layer comprising an olefin-based (co)polymer (a-2) having a melting point of 30°C or higher and lower than 120°C; (2) when the hot-melt layers are adhered to each other, the heat seal strength is 10 N/15 mm or more at 110°C; (3) the sealant film is a nonoriented film; and (4) the substrate film is at least one type selected from a nonoriented polypropylene film and a biaxially oriented polypropylene film.EFFECT: The laminate of the present invention has a high content percentage of a propylene copolymer and excellent low-temperature heat sealing property, and can achieve both of physical properties such as low-temperature heat sealing property and anti-blocking property and reduction in the production cost.SELECTED DRAWING: None

Description

The present invention relates to a laminate containing a sealant film and a base material, which contains a propylene-based copolymer at a high content, and is excellent in low-temperature heat-sealing property and blocking resistance.

Crystalline polypropylene films are widely used as heat-sealed packaging films. The crystalline polypropylene film is excellent in rigidity, heat resistance, etc., but since the heat seal temperature is high, the heat seal property is usually improved by laminating a sealant layer.

As a sealant film for packaging materials, a composition obtained by blending an ethylene-based copolymer with a propylene-based copolymer or a film using only an ethylene-based copolymer is widely used. For example, Patent Document 1 describes a laminate having excellent low-temperature heat-sealing properties, which comprises a sealant film containing a polypropylene resin, an ethylene / α-olefin random copolymer and a 1-butene / α-olefin random copolymer. Has been done.

Japanese Unexamined Patent Publication No. 11-221884

As described above, the propylene-based copolymer is inferior in low-temperature sealing property and does not have sufficient blocking resistance. Further, the ethylene-based copolymer is excellent in low-temperature sealing property, but its blocking resistance is not sufficient. On the other hand, packaging films are also required to reduce manufacturing costs.

The present invention provides a material containing a propylene-based copolymer as a main component, having excellent low-temperature heat-sealing properties, and capable of achieving both physical properties such as low-temperature heat-sealing properties and blocking resistance and reduction of manufacturing cost. The purpose is to do.

The present invention relates to, for example, the following [1] to [8].
[1] When the sealant film satisfying the following requirements (1) to (3) and the base film satisfying the requirement (4) are included, and the total mass of the sealant film and the base film is 100% by mass. A laminate containing 70% by mass or more of a propylene (co) polymer and / or a 1-butene (co) polymer.
(1) The sealant film has at least a heat-sealing layer containing an olefin-based (co) polymer (a-2) having a melting point of 30 ° C. or higher and lower than 120 ° C.
(2) The heat seal strength at 110 ° C. when the heat-sealing layers are bonded to each other is 10 N / 15 mm or more.
(3) The sealant film is a non-stretched film.
(4) The base film is at least one selected from unstretched polypropylene film and biaxially stretched polypropylene film.
[2] The laminate according to [1], wherein the olefin-based (co) copolymer (a-2) has at least a propylene / α-olefin copolymer and a 1-butene / α-olefin copolymer.
[3] In the heat-sealing layer, in addition to the olefin-based (co) polymer (a-2), an olefin-based (co) polymer (a-1) having a melting point of 120 ° C. or higher and 170 ° C. or lower is used. The laminate according to [1] or [2] including.
[4] The laminate according to [3], wherein the olefin-based (co) polymer (a-1) is a propylene (co) polymer.
[5] The method according to any one of [1] to [4], wherein at least one film selected from the sealant film and the base film includes at least one layer selected from a printing layer, a barrier layer and an embossed layer. Laminated body.
[6] The method for producing a laminate according to any one of [1] to [5], wherein at least one film selected from the sealant film and the base film contains a barrier layer, wherein the barrier layer is metal-deposited. A method for producing a laminate, which comprises a step of forming the sealant film or a base film as a single layer by a coating method or a coextrusion method, and a step of laminating the sealant film and the base film.
[7] A package formed by the laminate according to any one of [1] to [5].
[8] A molded product that is a recycled product of the laminate according to any one of [1] to [5] or the package according to claim 7.

The laminate of the present invention has a high content of propylene-based copolymer, is excellent in low-temperature heat-sealing property, and can realize both physical properties such as low-temperature heat-sealing property and blocking resistance and reduction of manufacturing cost. it can.

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-sealing properties to the laminate of the present invention, and the base film is a film that holds the sealant film.

The sealant film satisfies the following requirements (1) to (3).
(1) The sealant film has at least a heat-sealing layer containing an olefin-based (co) polymer (a-2) having a melting point of 30 ° C. or higher and lower than 120 ° C.

In the present invention, the "(co) polymer" is a concept including a homopolymer and a copolymer.
The heat-sealing layer is a layer that imparts heat-sealing property to the sealant film. The heat-sealed layer contains an olefin-based (co) polymer (a-2) having a melting point of 30 ° C. or higher and lower than 120 ° C.

Examples of the olefin-based (co) polymer (a-2) include a homopolymer of an α-olefin, a copolymer of the α-olefin and another α-olefin, and a monomer other than the α-olefin and the α-olefin. And the copolymer with. Specific examples of the olefin-based (co) polymer (a-2) include a homopolymer of ethylene and a copolymer of ethylene and an α-olefin having 3 or more carbon atoms (ethylene / α-olefin copolymer). ) And other ethylene (co) polymers, propylene homopolymers and propylene (co) polymers such as propylene and α-olefin copolymers with 4 or more carbon atoms (propylene / α-olefin copolymers). Examples thereof include a copolymer of 1-butene and an α-olefin having 5 or more carbon atoms (1-butene / α-olefin copolymer). Of these, propylene / α-olefin copolymers, 1-butene / α-olefin copolymers and ethylene / α-olefin copolymers are more preferable.

Examples of α-olefins having 3 or more carbon atoms that copolymerize with ethylene include propylene, 1-butene, 1-pentene, 3-methyl-1-butene, 4-methyl-1-pentene, 1-hexene, 1-octene, and the like. Examples thereof include α-olefins having 3 to 20 carbon atoms such as 1-decene, 1-dodecene, and 1-tetradecene. Examples of the α-olefin having 4 or more carbon atoms that copolymerize with propylene include the α-olefin other than propylene. Examples of the α-olefin having 5 or more carbon atoms that copolymerize with 1-butene include the α-olefins other than propylene and 1-butene.

The olefin-based (co) polymer (a-2) may be one kind of (co) polymer or two or more kinds of copolymers.
The olefin-based (co) copolymer (a-2) preferably contains at least a propylene / α-olefin copolymer and a 1-butene / α-olefin copolymer. Propylene / α-olefin copolymers are generally inexpensive, but do not have sufficient low temperature sealing and blocking resistance. On the other hand, the 1-butene / α-olefin copolymer is generally expensive, but has excellent low-temperature sealing property and blocking resistance. Since the olefin-based (co) copolymer (a-2) contains at least a propylene / α-olefin copolymer and a 1-butene / α-olefin copolymer, it is excellent in low-temperature sealing property and blocking resistance. , It becomes easy to realize both physical properties such as low-temperature heat-sealing property and blocking resistance and reduction of manufacturing cost.

When the olefin-based (co) copolymer (a-2) contains a propylene / α-olefin copolymer and a 1-butene / α-olefin copolymer, the olefin-based (co) polymer (a-2) The content ratio of the propylene / α-olefin copolymer is preferably 50 to 90% by mass, more preferably 55 to 80% by mass, and the content ratio of the 1-butene / α-olefin copolymer is preferably 10 to 10%. It is 50% by mass, more preferably 20 to 45% by mass.

More preferably, the olefin-based (co) polymer (a-2) contains a propylene / ethylene copolymer and a 1-butene / propylene copolymer.
The melting point of the olefin-based (co) polymer (a-2) is 30 ° C. or higher and lower than 120 ° C., preferably 40 to 110 ° C., more preferably 50 to 100 ° C. When the melting point of the olefin-based (co) polymer (a-2) is within the above range, a laminate having excellent low-temperature heat-sealing properties can be obtained.

The MFR measured under the conditions of 230 ° C. and 2.16 kg load according to ASTM D1238 of the olefin-based (co) polymer (a-2) is preferably 0.1 to 100 g / 10 min, more preferably 1 to 20 g. / 10 min.

The olefin-based (co) polymer (a-2) uses a known polymerization method such as a vapor phase method, a bulk method, or a slurry method in the presence of a known catalyst such as a Ziegler-Natta-based catalyst or a metallocene-based catalyst. It can be produced by polymerizing with. As a method of setting the melting point to 30 ° C. or higher and lower than 120 ° C., for example, when the polymerization conditions such as the amount of monomer feed are controlled and the polymerization is carried out with a Ziegler-Natta catalyst, the copolymer content is 20 mol% or more and 50. When polymerizing with a molar% or less and a metallocene-based catalyst, a method of controlling the comonomer content to 10 mol% or more and 50 mol% or less can be mentioned, and a copolymer having a target melting point can be obtained by this method. ..

The heat-sealed layer may contain a (co) polymer or the like other than the olefin-based (co) polymer (a-2).
The heat-sealing layer may be present in two or more layers, but is preferably one layer.
The sealant film may include a layer other than the heat-sealing layer.

(2) The heat seal strength at 110 ° C. when the heat-sealing layers are bonded to each other is 10 N / 15 mm or more.
The method for measuring the heat seal strength will be described in detail in Examples.

In the sealant film, the heat seal strength is 10 N / 15 mm or more, preferably 12 N / 15 mm or more, and more preferably 15 N / 15 mm or more. When the heat seal strength is 10 N / 15 mm or more, a laminate having excellent low temperature heat seal properties and heat seal strength can be obtained.
A sealant film satisfying the requirement (2) can be obtained by appropriately adjusting the melting point.

(3) The sealant film is a non-stretched film.
The sealant film is a non-stretched film that has not been stretched after being formed as a film. When the sealant film is a non-stretched film, a film having more flexibility and excellent heat sealing strength can be obtained.

The sealant film contains other resins, tackifiers, weather stabilizers, heat stabilizers, antistatic agents, antislip agents, antiblocking agents, lubricants, pigments, dyes, and plasticizers as long as the object of the present invention is not impaired. Additives such as agents, antioxidants, hydrochloric acid absorbents, antioxidants and the like can be included as needed.

The base film satisfies the requirement (4).
(4) The base film is at least one selected from unstretched polypropylene film and biaxially stretched polypropylene film.

The base film is a polypropylene film. Examples of the polypropylene constituting the polypropylene film include a propylene homopolymer and a copolymer containing 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 copolymerizing with propylene include α-olefins and diene compounds other than propylene. The propylene content (structural unit derived from propylene) in 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. It is 10 mol%.

Other α-olefins that copolymerize with propylene include ethylene, 1-butene, 1-pentene, 3-methyl-1-butene, 4-methyl-1-pentene, 1-hexene, 1-octene, and 1-decene. , 1-dodecene, 1-tetradecene and the like with 2 or 4 to 20 carbon atoms such as α-olefins can be exemplified.

As the polypropylene, the MFR measured under the conditions of 230 ° C. and a 2.16 kg load according to ASTM D1238 is preferably 0.1 to 10 g / 10 min, more preferably 0.5 to 8 g / 10 min, and has a melting point ( Tm) is preferably 130 to 165 ° C, more preferably 135 to 150 ° C.

Specifically, the polypropylene includes a propylene homopolymer, a propylene / ethylene random copolymer, a propylene / 1-butene random copolymer, a propylene / 1-butene / ethylene random copolymer, and a propylene / 1-. Examples thereof include a hexene random copolymer, a propylene / 3-methyl-1-butene random copolymer, and a propylene / 4-methyl-1-pentenrandom copolymer. The polypropylene may be used alone or in combination of two or more.

The polypropylene can be produced by polymerizing a monomer by a known polymerization method such as a vapor phase method, a bulk method, or a slurry method in the presence of a known catalyst such as a Ziegler-Natta catalyst or a metallocene catalyst. ..
The polypropylene may be the same (co) polymer as the olefin-based (co) polymer (a-2) contained in the sealant film.

The base film is at least one selected from a non-stretched polypropylene film in which a film formed from polypropylene is not stretched and a biaxially stretched polypropylene film obtained by subjecting a biaxially stretched film. As the stretching method, a known method for producing a stretched film can be used. Specific examples thereof include roll stretching, tenter stretching, and tubular stretching. The draw ratio is 1.5 to 20 times, usually 2 to 15 times.

The base film may be composed of one layer or may be composed of a plurality of layers.
The base film includes other resins, tackifiers, weather stabilizers, heat stabilizers, antistatic agents, antislip agents, antiblocking agents, lubricants, pigments, dyes, plasticizers, antiaging agents, and hydrochloric acid absorbers. , Additives such as antioxidants can be included.

The laminate of the present invention contains 70% by mass or more of the propylene (co) polymer and / or 1-butene (co) polymer when the total mass of the sealant film and the base film is 100% by mass. Including. That is, the laminate of the present invention has only one of a propylene (co) polymer and a 1-butene (co) polymer when the total mass of the sealant film and the base film is 100% by mass. 70% by mass or more, or 70% by mass or more of propylene (co) polymer and 1-butene (co) polymer in total. The content of the propylene (co) polymer and / or 1-butene (co) polymer is preferably 80 to 100% by mass, more preferably 90 to 100% by mass. When the laminate of the present invention contains a propylene (co) polymer and / or a 1-butene (co) polymer in the above range, it is preferable in terms of environmental problems and excellent in low temperature heat sealability.

Examples of the propylene (co) polymer include a propylene homopolymer, a copolymer of propylene and ethylene, or an α-olefin having 4 to 20 carbon atoms. 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, and 1 -Dodecene, 1-tetradecene and the like can be mentioned.

Examples of the 1-butene (co) polymer include a homopolymer of 1-butene, a copolymer of 1-butene and ethylene, or an α-olefin having 5 to 20 carbon atoms. 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, and 1 -Tetradecene and the like can be mentioned.

Both the propylene (co) polymer and the 1-butene (co) polymer may be a (co) polymer contained as an olefin-based (co) polymer (a-2) in the sealant film. It may be a (co) polymer contained as polypropylene in the base film, or may be a (co) polymer contained in a film other than the sealant film and the base film.

In addition to the olefin-based (co) polymer (a-2), the heat-sealing layer contained in the sealant film is an olefin-based (co) polymer (a-1) having a melting point of 120 ° C. or higher and 170 ° C. or lower. ) Can be included. When the heat-sealing layer contains an olefin-based (co) polymer (a-1) in addition to the olefin-based (co) polymer (a-2), film blocking during and after film formation is unlikely to occur.

Examples of the olefin-based (co) polymer (a-1) include the same (co) polymer as the above-mentioned olefin-based (co) polymer (a-2).
As the olefin-based (co) polymer (a-1), a propylene (co) polymer is more preferable.

The olefin-based (co) polymer (a-1) uses a known polymerization method such as a vapor phase method, a bulk method, or a slurry method in the presence of a known catalyst such as a Ziegler-Natta-based catalyst or a metallocene-based catalyst. It can be produced by polymerizing with. As a method of setting the melting point to 120 ° C. or higher and 170 ° C. or lower, for example, in the case of polymerization with a Ziegler-Natta catalyst by controlling the polymerization conditions such as the amount of monomer feed, the copolymer content is less than 20 mol% and metallocene. In the case of polymerization with a system catalyst, a method of controlling the comonomer content to less than 10 mol% can be mentioned, and a copolymer having a target melting point can be obtained by this method.

The thickness of the sealant film is usually 3 to 50 μm, preferably 5 to 25 μm, and the thickness of the base film is usually 15 to 70 μm, preferably 20 to 50 μm. When there are a plurality of sealant films, it is preferable that each sealant film has the above thickness. The thickness of the entire laminate of the present invention is usually 20 to 100 μm, preferably 25 to 70 μm.

Various layers can be included in order to impart a specific function to the sealant film and the base film. For example, the sealant film and the base film can include functional material layers such as a printing layer, a barrier layer and an embossed layer.

A resin film on which an inorganic compound or an inorganic oxide is vapor-deposited, a metal foil, a coating film of a resin having a special function, a resin film on which a pattern is printed, or the like can be used as a functional material layer.
Here, as the resin film used, it is possible to use the same resin film as the resin film used for the base film, and further, the same plastic compounding agent, additive, etc. can be used for other performances. It can also be added in an arbitrary amount depending on the purpose as long as it does not adversely affect the substance.

As the resin film, for example, one kind or two or more kinds of resins selected from the same group of resins as the resin for the base film are used, and the extrusion method, the cast molding method, the T-die method, the cutting method, the inflation method, etc. It can be produced by a conventionally used film-forming method, or by a multi-layer co-extrusion film-forming method using two or more kinds of resins. Further, from the viewpoint of film strength, dimensional stability, and heat resistance, the film can be stretched in the uniaxial or biaxial directions by using, for example, a tenter method or a tubular method.

For example, in a laminate in which at least one film selected from the sealant film and the base film contains a barrier layer, the barrier layer is used as a layer in the sealant film or the base film by a metal deposition, coating method or coextrusion method. It can be produced by a method for producing a laminated body, which includes a step of forming and a step of laminating the sealant film and the base film.

Examples of the laminated body 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 may be provided between the sealant film and the base film.

The laminate of the present invention may be produced by laminating a sealant film and a base film via an adhesive layer by dry lamination, non-solvent lamination, sand lamination or the like, or a sealant film and a base material by melt extrusion lamination. It may be manufactured by laminating a film. Above all, the method of laminating by dry lamination or melt extrusion lamination is preferable.

As described above, the laminate of the present invention has a high content of propylene copolymer, excellent low temperature heat sealability, excellent blocking resistance, physical properties such as low temperature heat sealability and blocking resistance, and low manufacturing cost. It is possible to achieve both.

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-sealing properties. Further, the package formed by the laminate of the present invention thus obtained has the same heat-sealing strength as the conventional product when molded at the conventional heat-sealing temperature (for example, over 100 ° C. to 160 ° C.). It can be maintained above.

For example, the sealant film layers of the laminate face each other, or the sealant film layer of the laminate film and another film face each other, and then at least a part of the periphery thereof so as to have a desired container shape from the outer surface side. The container can be manufactured by heat-sealing the film. Further, by heat-sealing the entire periphery, a sealed bag-shaped container can be manufactured. When this bag-shaped container molding process is combined with the content filling process, that is, the bottom and sides of the bag-shaped container are heat-sealed, the contents are filled, and then the top is heat-sealed to manufacture a package. can do. This package can be used for an automatic packaging device for solids, powders, or liquid materials such as snack foods and breads.

In addition, the contents are filled in a container in which the laminate or sheet is previously molded into a cup shape by vacuum molding or pneumatic molding, a container obtained by injection molding, or a container formed from a paper base material, and then the present. By coating the laminate of the present invention as a lid material and heat-sealing the upper part or the side portion of the container, a container in which the contents are packaged can be obtained. This container is suitably used for packaging instant noodles, miso, jelly, pudding, snacks and the like.

The recycled product of the laminated body or the package can also be effectively used. The molded product, which is a recycled product of the laminate or the package, makes it possible to reduce the amount of newly polymerized plastic used, and is an article that can contribute to the reduction of the environmental load.

Next, the laminate of the present invention will be described in more detail with reference to examples, but the present invention is not limited thereto.
The materials used in Examples and Comparative Examples are shown below.

rPP-1: Random polypropylene (MFR (230 ° C, 2.16 kg load, conforming to ASTM D1238): 7 g / 10 min, melting point: 138 ° C, propylene content: 96 mol%)
BPR-1: 1-butene-propylene copolymer (MFR (230 ° C, 2.16 kg load, conforming to ASTM D1238): 9 g / 10 min, MFR (190 ° C, 2.16 kg load, conforming to ASTM D1238): 4 g / 10min, melting point: 100 ° C., 1-butene content: 85 mol%, propylene content: 15 mol%)
BPR-2: 1-butene-propylene copolymer (MFR (230 ° C, 2.16 kg load, conforming to ASTM D1238): 9 g / 10 min, MFR (190 ° C, 2.16 kg load, conforming to ASTM D1238): 4 g / 10min, melting point: 58 ° C., 1-butene content: 75 mol%, propylene content: 25 mol%)
PER-1: Propylene / ethylene copolymer (MFR (230 ° C, 2.16 kg load, conforming to ASTM D1238): 8 g / 10 min, MFR (190 ° C, 2.16 kg load, conforming to ASTM D1238): 3.7 g / 10min, Vicat softening point: 76.7 ° C., Shore D hardness: 40, propylene content: 87 mol%, ethylene content: 13 mol%)
The heat seal strength and the dynamic friction coefficient and blocking force, which are surface characteristics, were measured by the following measuring methods.

[Measurement method of heat seal strength]
The sealant film surfaces of the two laminated bodies are overlapped with each other, or the two single-layer films are overlapped with each other, and 70 ° C., 80 ° C., 90 ° C., 100 ° C., 110 ° C., 120 ° C., 130 ° C., 140 ° C., 150 The film was heat-sealed at a pressure of 0.2 MPa at ° C. or 160 ° C. for 1 second with a seal bar width of 5 mm, and then allowed to cool. Next, each test piece having a width of 15 mm was cut out from the test piece obtained by heat sealing, and for each test piece, the peeling strength when the heat-sealed part was peeled off at a crosshead speed of 300 mm / min was measured, and the value was measured as heat. The seal strength was used.

[Measurement method of dynamic friction coefficient]
The laminate is made into strips with a width of 64 mm, the sealant surfaces of the two strips are overlapped with each other, a weight of 200 g is placed on the laminate, one laminate is fixed, and the other laminate has a speed of 200 mm / min. The coefficient of friction was measured by pulling with.

[Measuring method of blocking force]
The laminate is made into strips with a width of 200 mm, the sealant surfaces of the two strips are overlapped with each other, placed in an air oven at 50 ° C., and a load of 20 kg is applied from the top of the stacked laminates to cure for 3 days. did. Then, the laminate was taken out from the air oven, and the blocking force was measured by peeling the two strip-shaped laminates at a speed of 200 mm / min. The smaller the value of the blocking force, the better the anti-blocking property.

[Example 1]
40 parts by mass of rPP-1, 20 parts by mass of BPR-1 and 40 parts by mass of PER-1 are blended, and silica particles (average particle diameter 3 μm) and erucic acid amide are added as anti-slip agents, and the contents are 4900 ppm and 2000 ppm, respectively. To prepare a resin composition for producing a sealant film.

Using two extruders to which a T-die was connected, the resin composition for producing a sealant film and rPP-1 for producing a base film were supplied to each extruder, and the die and resin temperature were set to 230 ° C. The extrusion amount of each extruder was adjusted to, and coextrusion molding was performed to produce a laminate in which an unstretched base film having a thickness of 50 μm and an unstretched sealant film having a thickness of 20 μm were laminated. Using this laminated body, the heat seal strength, the dynamic friction coefficient, and the blocking force were determined by the above-mentioned measuring method. The results are shown in Table 1.

[Examples 2 to 5, Comparative Examples 1 to 6]
A laminate was produced in the same manner as in Example 1 except that the composition of the composition for producing a sealant film was changed to the composition shown in Table 1. Using each of these laminates, the heat seal strength, the dynamic friction coefficient, and the blocking force were determined by the above-mentioned measuring methods. The results are shown in Table 1. Numerical values related to the laminated body in Table 1 indicate parts by mass.

Claims (8)

When the sealant film satisfying the following requirements (1) to (3) and the base film satisfying the requirement (4) are included and the total mass of the sealant film and the base film is 100% by mass, propylene. A laminate containing 70% by mass or more of a (co) polymer and / or a 1-butene (co) polymer.
(1) The sealant film has at least a heat-sealing layer containing an olefin-based (co) polymer (a-2) having a melting point of 30 ° C. or higher and lower than 120 ° C.
(2) The heat seal strength at 110 ° C. when the heat-sealing layers are bonded to each other is 10 N / 15 mm or more.
(3) The sealant film is a non-stretched film.
(4) The base film is at least one selected from unstretched polypropylene film and biaxially stretched polypropylene film. The laminate according to claim 1, wherein the olefin-based (co) copolymer (a-2) has at least a propylene / α-olefin copolymer and a 1-butene / α-olefin copolymer. The claim that the heat-sealing layer contains, in addition to the olefin-based (co) polymer (a-2), an olefin-based (co) polymer (a-1) having a melting point of 120 ° C. or higher and 170 ° C. or lower. The laminate according to 1 or 2. The laminate according to claim 3, wherein the olefin-based (co) polymer (a-1) is a propylene (co) polymer. The laminate according to any one of claims 1 to 4, wherein at least one film selected from the sealant film and the base film includes at least one layer selected from a printing layer, a barrier layer and an embossed layer. The method for producing a laminate according to any one of claims 1 to 5, wherein at least one film selected from the sealant film and the base film includes a barrier layer, wherein the barrier layer is metal-deposited, coated, or co-extruded. A method for producing a laminate, which comprises a step of forming the sealant film or a base film as a single layer in the base film by an extrusion method and a step of laminating the sealant film and the base film. A package formed by the laminate according to any one of claims 1 to 5. A molded product that is a recycled product of the laminate according to any one of claims 1 to 5 or the package according to claim 7.