WO2025220713A1 - Laminate and method for manufacturing laminate - Google Patents

Abstract

Provided is a laminate including a 3-methyl-1-butene-based polymer and a polypropylene-based resin, wherein: the laminate has at least two layers including an A layer formed from a first resin composition and a B layer formed from a second resin composition; the 3-methyl-1-butene-based polymer content of the first resin composition, the polypropylene-based resin content of the first resin composition, the 3-methyl-1-butene-based polymer content of the second resin composition, and the polypropylene-based resin content of the second resin composition are within prescribed ranges; and the 3-methyl-1-butene-based polymer content in terms of mass within 100 mass% of the total amount of resin components in the first resin composition is greater than the 3-methyl-1-butene-based polymer content in terms of mass within 100 mass% of the total amount of resin components in the second resin composition. Also provided is a method for manufacturing the aforementioned laminate.

Description

Laminate and method for manufacturing laminate

The present invention relates to a laminate and a method for manufacturing a laminate.

Thermoplastic polyolefins are suitable for and commonly used in extrusion-molded products such as film products and injection-molded products, but are not suitable for use in high-temperature environments, such as temperatures above 200°C.
Therefore, development is underway on plastic films made from thermoplastic polyolefins that can be used in higher temperature environments.
For example, Patent Document 1 discloses a stretched film obtained by stretching, at a draw ratio of 2 or more, an unstretched film formed from a homopolymer of 3-methylbutene-1 or a copolymer of 3-methylbutene-1 and an α-olefin and/or polyene having 2 to 12 carbon atoms, the melt viscosity of which is 1×10 poise ^or more as measured at 330° C. and a shear rate of 0.1 (1/sec).
Furthermore, Patent Document 2 discloses a release film comprising a uniaxially stretched film formed from a composition containing 5 to 95 parts by weight of a 3-methyl-1-butene polymer (A) and 5 to 95 parts by weight of a 4-methyl-1-pentene polymer (B) [the total amount of components (A) and (B) is 100 parts by weight], and characterized in that at least one surface of the uniaxially stretched film is roughened by embossing.

Japanese Unexamined Patent Publication No. 176741/1986 Japanese Patent Application Laid-Open No. 2002-137231

As mentioned above, thermoplastic polyolefins are required to have good heat resistance so that they can be used in high-temperature environments. On the other hand, thermoplastic polyolefins are required to have good moldability because they are subjected to various molding processes such as stretching, compression molding, pressure molding, and vacuum molding to produce the desired molded products. However, it has been difficult to achieve both good heat resistance and moldability.
Therefore, an object of the present invention is to provide a laminate having good heat resistance and moldability, and a method for producing the laminate.

As a result of extensive research, the present inventors have found that the above-mentioned problems can be solved by forming a laminate having a specific structure.
That is, the present invention includes the following inventions.
[1] A laminate containing a 3-methyl-1-butene polymer and a polypropylene resin,
the laminate includes at least two layers: a layer A formed from a first resin composition and a layer B formed from a second resin composition;
the content of the 3-methyl-1-butene polymer in the first resin composition is 10 to 100% by mass, based on 100% by mass of the total amount of resin components in the first resin composition;
the content of the polypropylene resin in the first resin composition is 0 to 90% by mass relative to 100% by mass of the total amount of resin components in the first resin composition;
the content of the 3-methyl-1-butene polymer in the second resin composition is 0 to 90% by mass relative to 100% by mass of the total amount of resin components in the second resin composition;
the content of the polypropylene resin in the second resin composition is 10 to 100% by mass, based on 100% by mass of the total amount of resin components in the second resin composition;
a laminate in which the content of the 3-methyl-1-butene polymer in the first resin composition based on mass, relative to 100% by mass of all resin components, is greater than the content of the 3-methyl-1-butene polymer in the second resin composition based on mass, relative to 100% by mass of all resin components.
[2] The content of the 3-methyl-1-butene polymer in the second resin composition is 0 to 40% by mass, based on 100% by mass of the total amount of resin components in the second resin composition;
The laminate according to [1] above, wherein the content of the polypropylene-based resin in the second resin composition is 60 to 100 mass% in 100 mass% of the total amount of resin components in the second resin composition.
[3] The laminate according to the above [1] or [2], wherein at least one layer A and at least one layer B are directly laminated together.
[4] The laminate according to the above [3], wherein the A layer and the B layer have interlayer adhesion.
[5] The laminate according to any one of the above [1] to [4], containing 1 to 100% by mass of recycled raw materials.
[6] The laminate according to any one of the above [1] to [5], wherein the ratio of the thickness of the A layer to the thickness of the B layer [A layer/B layer] is 0.1 to 10.
[7] The laminate according to any one of the above [1] to [6], having a yellowness index (YI) of 3.50 or less.
[8] The laminate according to any one of the above [1] to [7], wherein the 3-methyl-1-butene polymer is at least one selected from the group consisting of a 3-methyl-1-butene homopolymer and a copolymer of 3-methyl-1-butene with at least one selected from the group consisting of ethylene and an α-olefin having 3 to 20 carbon atoms other than 3-methyl-1-butene.
[9] The laminate according to any one of the above [1] to [8], wherein the first resin composition further contains an antioxidant.
[10] The laminate according to the above [9], wherein the antioxidant is at least one selected from the group consisting of phenol-based antioxidants and phosphorus-based antioxidants.
[11] The laminate according to any one of the above [1] to [10], wherein the absolute value of the linear expansion coefficient at 160 to 260°C is 2,000 ppm/°C or less.
[12] The laminate according to any one of the above [1] to [11], which is a film.
[13] A method for producing the laminate according to any one of [1] to [12] above,
A method for producing a laminate, comprising: a step (I) of melt-extruding the first resin composition.
[14] The method for producing a laminate according to the above [13], wherein the first resin composition is melted in an inert atmosphere or in a low-oxygen state during the step (I).
[15] The method for producing a laminate according to the above [13] or [14], wherein the first resin composition is melted at 280 to 323°C in the step (I).
[16] The method for producing a laminate according to any one of [13] to [15] above, further comprising: a step (II) of solidifying the molten extrudate of the first resin composition obtained in the step (I) using a casting drum, wherein the temperature of the casting drum is 40 to 250°C.
[17] Furthermore, in the step (I), the melt of the second resin composition and the melt of the first resin composition are co-extruded through a T-die. The method for producing a laminate according to any one of [13] to [16].
[18] The method for producing a laminate according to the above-mentioned [17], wherein a draft ratio [Tt/Ft], which is a ratio of a gap thickness (Tt) of a lip portion of the T-die to a thickness (Ft) of a laminate formed by coextrusion from the lip portion, is 1 to 30.

The present invention provides a laminate with good heat resistance and moldability, as well as a method for producing such a laminate.

The present invention will be described below based on examples of embodiments (hereinafter also referred to as "one aspect of the present invention"). However, each embodiment shown below is an example for embodying the technical idea of the present invention, and the present invention is not limited to the following description.
The present invention also includes any selected or combined embodiment of the matters described in this specification.
In this specification, preferred embodiments are shown, but a combination of two or more of the individual preferred embodiments is also a preferred embodiment. The preferred definitions can be selected arbitrarily, and for example, a combination of preferred definitions can be said to be more preferred.
In this specification, unless otherwise specified, the expression "XX to YY" as a numerical range means "XX or more and YY or less" (XX represents the lower limit and YY represents the upper limit). For example, when the numerical range is simply expressed as "10 to 90," it represents a range of 10 or more and 90 or less.
In this specification, the lower and upper limits of numerical ranges (such as the values of each property, the content of each component, the content of each structural unit, the production conditions, and values calculated therefrom, the properties, and the conditions) described in stages can be independently combined. For example, a description of "preferably 10 to 90, more preferably 30 to 60" for the same item can be combined with the "preferable lower limit (10)" and the "more preferable upper limit (60)" to form "10 to 60."
Furthermore, for example, based on the description of a numerical range that is "preferably 10 to 90, more preferably 30 to 60," the upper limit may not be particularly specified and only the lower limit may be specified as "10 or more" or "30 or more," and similarly, the lower limit may not be particularly specified and only the upper limit may be specified as "90 or less" or "60 or less." The same applies when the upper end of the numerical range is "less than" and when the lower limit is "greater than."
As described above, for example, from the description of "preferably 10 or more, more preferably 30 or more" and the description of "preferably 90 or less, more preferably 60 or less" for the same item, the "preferable lower limit (10)" and the "more preferable upper limit (60)" can be combined to form "10 or more and 60 or less." Similarly, as described above, only the lower limit can be specified as "10 or more" or "30 or more," and similarly, only the upper limit can be specified as "90 or less" or "60 or less." The same applies when the terms "or more" and "or less" in the above explanation are written as "more than" and "less than," respectively. That is, for example, based on the description of "preferably more than 10 and less than 90, more preferably more than 30 and 60," the respective upper and lower limits can be combined to form "more than 10 and 60 or less" or "30 or more and less than 90."

[Laminate]
The laminate of the present invention is
A laminate containing a 3-methyl-1-butene polymer and a polypropylene resin,
the laminate includes at least two layers: a layer A formed from a first resin composition and a layer B formed from a second resin composition;
the content of the 3-methyl-1-butene polymer in the first resin composition is 10 to 100% by mass, based on 100% by mass of the total amount of resin components in the first resin composition;
the content of the polypropylene resin in the first resin composition is 0 to 90% by mass relative to 100% by mass of the total amount of resin components in the first resin composition;
the content of the 3-methyl-1-butene polymer in the second resin composition is 0 to 90% by mass relative to 100% by mass of the total amount of resin components in the second resin composition;
the content of the polypropylene resin in the second resin composition is 10 to 100% by mass, based on 100% by mass of the total amount of resin components in the second resin composition;
The laminate is such that the content of the 3-methyl-1-butene polymer in the first resin composition based on mass, relative to 100% by mass of all resin components, is greater than the content of the 3-methyl-1-butene polymer in the second resin composition based on mass, relative to 100% by mass of all resin components.
By satisfying the above-mentioned constitution, the laminate of the present invention can have good heat resistance and moldability.

Below, we will first explain the 3-methyl-1-butene polymer and polypropylene resin contained in the laminate of the present invention, and then explain the layer structure and other aspects of the laminate of the present invention.

<3-methyl-1-butene polymer>
The 3-methyl-1-butene polymer (hereinafter also abbreviated as "P3MB") may be a 3-methyl-1-butene homopolymer or a copolymer of 3-methyl-1-butene and an unsaturated hydrocarbon other than 3-methyl-1-butene. Examples of the unsaturated hydrocarbon include ethylene and an α-olefin other than 3-methyl-1-butene, and from the viewpoint of good copolymerizability, an α-olefin having 3 to 20 carbon atoms other than 3-methyl-1-butene is preferred.
From the viewpoint of suitably exhibiting the physical properties of 3-methyl-1-butene, it is preferable that P3MB be at least one selected from the group consisting of 3-methyl-1-butene homopolymers and copolymers of 3-methyl-1-butene with at least one selected from the group consisting of ethylene and α-olefins having 3 to 20 carbon atoms other than 3-methyl-1-butene.
Hereinafter, in this specification, unless otherwise specified, the term "α-olefin" refers to an α-olefin other than 3-methyl-1-butene.

When P3MB is a copolymer of 3-methyl-1-butene and at least one selected from the group consisting of ethylene and an α-olefin, from the viewpoint of more easily obtaining good heat resistance and moldability, the content of structural units derived from at least one selected from the group consisting of ethylene and an α-olefin in the copolymer is preferably more than 0 mol % and not more than 20 mol % relative to 100 mol % of the total amount of structural units derived from monomers.
From the viewpoint of suitably exhibiting the physical properties of at least one selected from the group consisting of ethylene and α-olefins, the content of structural units derived from at least one selected from the group consisting of ethylene and α-olefins in the copolymer is more preferably 0.1 mol % or more, even more preferably 0.3 mol % or more, and still more preferably 0.5 mol % or more, based on 100 mol % of the total amount of structural units derived from monomers.
Furthermore, from the viewpoint of easily maintaining the physical properties of 3-methyl-1-butene and more easily obtaining good heat resistance and moldability, the content of structural units derived from at least one selected from the group consisting of ethylene and α-olefins in the copolymer is more preferably 15 mol% or less, even more preferably 10 mol% or less, and still more preferably 5 mol% or less, based on 100 mol% of the total amount of structural units derived from monomers.
From the above viewpoint, the content of structural units derived from at least one selected from the group consisting of ethylene and α-olefins in the copolymer is more preferably 0.1 to 15 mol %, even more preferably 0.3 to 10 mol %, and still more preferably 0.5 to 5 mol %, based on 100 mol % of the total amount of structural units derived from monomers.
Here, in this specification, the "total amount of structural units derived from monomers" means, for example, structural units contained due to impurities in the polymerization solvent and monomers when polymerizing a polymer, as well as components necessary for polymerizing a polymer, such as catalysts, polymerization initiators, chain transfer agents, and coupling agents, but does not include structural units derived from components other than monomers.
The content of structural units derived from at least one selected from the group consisting of ethylene and α-olefins in the copolymer can be determined by Fourier transform infrared spectrophotometer (FT-IR). Specifically, it can be measured by the method described in the examples below.

When P3MB is a copolymer of 3-methyl-1-butene and at least one selected from the group consisting of ethylene and an α-olefin, the content of structural units derived from 3-methyl-1-butene in the copolymer is preferably 80 mol % or more and less than 100 mol % relative to the total amount of structural units derived from monomers (100 mol %), from the viewpoint of more easily obtaining good heat resistance and moldability.
Furthermore, from the viewpoint of easily maintaining the physical properties of 3-methyl-1-butene and more easily obtaining good heat resistance and moldability, the content of structural units derived from 3-methyl-1-butene in the copolymer is more preferably 85 mol% or more, even more preferably 90 mol% or more, and still more preferably 95 mol% or more, based on 100 mol% of the total amount of structural units derived from monomers.
Furthermore, from the viewpoint of suitably exhibiting the physical properties of at least one selected from the group consisting of ethylene and α-olefins, the content of structural units derived from 3-methyl-1-butene in the copolymer is more preferably 99.9 mol % or less, even more preferably 99.7 mol % or less, and still more preferably 99.5 mol % or less, based on 100 mol % of the total amount of structural units derived from monomers.
From the above viewpoints, the content of structural units derived from 3-methyl-1-butene is more preferably 85 to 99.9 mol %, even more preferably 90 to 99.7 mol %, and still more preferably 95 to 99.5 mol %, based on 100 mol % of the total amount of structural units derived from monomers.

From the viewpoint of suitably exhibiting the physical properties of 3-methyl-1-butene, the α-olefin having 3 to 20 carbon atoms is preferably an α-olefin having 4 to 16 carbon atoms, more preferably an α-olefin having 4 to 12 carbon atoms, and even more preferably an α-olefin having 4 to 10 carbon atoms. The α-olefin having 3 to 20 carbon atoms may be linear or branched.
Examples of the α-olefins having 3 to 20 carbon atoms include propylene, 1-butene, 1-pentene, 1-hexene, 3-methyl-1-pentene, 3-ethyl-1-pentene, 4-methyl-1-pentene, 4-methyl-1-hexene, 4,4-dimethyl-1-hexene, 4,4-dimethyl-1-pentene, 4-ethyl-1-hexene, 3-ethyl-1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, 1-undecene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, and 1-eicosene.
The α-olefins having 3 to 20 carbon atoms may be used alone or in combination of two or more.

From the viewpoint of a balance between heat resistance and moldability, the melting point of P3MB is preferably 260 to 310°C, more preferably 265 to 305°C, even more preferably 270 to 300°C, still more preferably 275 to 295°C, and even more preferably 280 to 290°C.
The melting point can be measured by the method described in the Examples below.

From the viewpoint of the balance between the fluidity of the resin composition during molding and the mechanical strength of the resulting laminate, the melt viscosity of P3MB is preferably 10 to 9,500 Pa s, more preferably 50 to 5,000 Pa s, even more preferably 100 to 2,000 Pa s, and still more preferably 200 to 1,000 Pa s.
The melt viscosity can be measured by the method described in the examples below.

The method for producing P3MB is not particularly limited, and it can be produced using well-known catalysts such as Ziegler-Natta catalysts and metallocene catalysts. Furthermore, P3MB can be obtained as a powder by homopolymerizing 3-methyl-1-butene or copolymerizing 3-methyl-1-butene with the above-mentioned α-olefins in the presence of a catalyst, as described in, for example, JP-A-61-103910.
The stereoregularity of P3MB may be isotactic or syndiotactic, and the copolymer may be a random copolymer, a block copolymer, or an alternating copolymer.

<Polypropylene resin>
As the polypropylene-based resin, known polypropylene-based resins can be used.
The content of structural units derived from propylene in the polypropylene-based resin is preferably 65 to 100 mol%, more preferably 80 to 100 mol%, even more preferably 85 to 100 mol%, still more preferably 90 to 100 mol%, and still more preferably 95 to 100 mol%, based on 100 mol% of the total amount of structural units derived from monomers.

The polypropylene-based resin may contain structural units derived from monomers other than propylene. Examples of structural units derived from monomers other than propylene include structural units derived from ethylene and structural units derived from α-olefins such as 1-butene, 1-hexene, 1-heptene, 1-octene, 4-methyl-1-pentene, 1-nonene, and 1-decene.
When the polypropylene-based resin contains structural units derived from a monomer other than propylene, the polypropylene-based resin may be a random copolymer or a block copolymer.

Examples of polypropylene-based resins include homopolypropylene, propylene-ethylene random copolymers, propylene-ethylene block copolymers, propylene-butene random copolymers, propylene-butene block copolymers, propylene-ethylene-butene random copolymers, propylene-pentene random copolymers, propylene-hexene random copolymers, propylene-octene random copolymers, propylene-ethylene-pentene random copolymers, propylene-ethylene-hexene random copolymers, and modified products thereof.
The polypropylene resin may be used alone or in combination of two or more kinds.

The melt flow rate (MFR) of the polypropylene resin measured under conditions of 230°C and 21.6 N is preferably 0.05 to 20 g/10 min, more preferably 0.1 to 5 g/10 min, even more preferably 0.2 to 3 g/10 min, and still more preferably 0.3 to 1 g/10 min, from the viewpoint of more easily obtaining good heat resistance and moldability.
The melt flow rate (MFR) of the polypropylene resin measured under conditions of 230°C and 21.6N can be measured in accordance with JIS K 7210:1999.

The melting point of the polypropylene resin is preferably 120 to 180°C, more preferably 130 to 176°C, even more preferably 140 to 174°C, and even more preferably 150 to 170°C.
The melting point of the polypropylene resin can be measured in accordance with JIS K 7121:2012.

<Laminated structure>
Next, the laminate structure of the laminate of the present invention will be described.
The laminate of the present invention includes at least two layers: a layer A formed from a first resin composition and a layer B formed from a second resin composition.

The number of layers A contained in the laminate of the present invention is one or more, preferably two or more, from the viewpoint of obtaining good heat resistance.
The number of layers A contained in the laminate of the present invention is preferably 5 or less, more preferably 4 or less, and even more preferably 3 or less, from the viewpoint of more easily obtaining good moldability.
From the above viewpoint, the number of layers A contained in the laminate of the present invention is preferably 1 to 5 layers, more preferably 2 to 4 layers, and even more preferably 2 to 3 layers.

The number of layers B contained in the laminate of the present invention is one or more from the viewpoint of obtaining good moldability.
The number of layers B contained in the laminate of the present invention is preferably 4 or less, more preferably 3 or less, and even more preferably 2 or less, from the viewpoint of more easily obtaining good heat resistance.
From the above viewpoint, the number of layers B contained in the laminate of the present invention is preferably 1 to 4 layers, more preferably 1 to 3 layers, and even more preferably 1 or 2 layers.

The total number of layers A and B contained in the laminate of the present invention is 2 or more, preferably 3 or more, from the viewpoint of obtaining good heat resistance and moldability.
From the viewpoint of productivity, the total number of A layers and B layers contained in the laminate of the present invention is preferably 9 layers or less, more preferably 6 layers or less, and even more preferably 4 layers or less.
From the above viewpoint, the total number of layers A and layers B contained in the laminate of the present invention is preferably 2 to 9 layers, more preferably 3 to 6 layers, and even more preferably 3 to 4 layers.

Examples of the layer structure of the laminate of the present invention include the following layer structures.
2 layers: Layer A/Layer B 3 layers: Layer A/Layer B/Layer A, or Layer B/Layer A/Layer B 4 layers: Layer A/Layer B/Layer A/Layer B 5 layers: Layer A/Layer B/Layer A/Layer B/Layer A/Layer B, or Layer B/Layer A/Layer B/Layer A/Layer B Although the layers A and B may be laminated directly or via another layer, it is preferable that at least one layer A and at least one layer B are laminated directly, and it is more preferable that all of the layers A and B are laminated directly.
Among the above layer configurations, from the viewpoint of making it easier to obtain good heat resistance and moldability, a layer configuration including at least Layer A/Layer B/Layer A is preferred, and a three-layer configuration of Layer A/Layer B/Layer A is more preferred.

In one embodiment of the present invention, when Layer A and Layer B are directly laminated together, there is interlayer adhesion between Layer A and Layer B. Although the details of why Layer A and Layer B exhibit interlayer adhesion are unknown, it is presumed that one of the reasons is the good affinity between the P3MB contained in Layer A and the polypropylene resin contained in Layer B.
The interlayer adhesion between the A layer and the B layer can be evaluated by the method described in the examples below.

From the viewpoint of making it easier to obtain good heat resistance, the thickness of layer A is preferably 1 μm or more, more preferably 2 μm or more, even more preferably 4 μm or more, still more preferably 6 μm or more, and even more preferably 8 μm or more.
Furthermore, from the viewpoint of making it easier to obtain good moldability, the thickness of layer A is preferably 500 μm or less, more preferably 200 μm or less, even more preferably 100 μm or less, even more preferably 50 μm or less, and even more preferably 25 μm or less.
From the above viewpoint, the thickness of layer A is preferably 1 to 500 μm, more preferably 2 to 200 μm, even more preferably 4 to 100 μm, still more preferably 6 to 50 μm, and even more preferably 8 to 25 μm.

From the viewpoint of making it easier to obtain good moldability, the thickness of layer B is preferably 1 μm or more, more preferably 2 μm or more, even more preferably 4 μm or more, still more preferably 6 μm or more, and even more preferably 8 μm or more.
Furthermore, from the viewpoint of making it easier to obtain good heat resistance, the thickness of layer B is preferably 500 μm or less, more preferably 200 μm or less, even more preferably 100 μm or less, still more preferably 50 μm or less, and even more preferably 25 μm or less.
From the above viewpoints, the thickness of layer B is preferably 1 to 500 μm, more preferably 2 to 200 μm, even more preferably 4 to 100 μm, still more preferably 6 to 50 μm, and even more preferably 8 to 25 μm.

The ratio of the thickness of layer A to the thickness of layer B [layer A/layer B] is preferably 0.1 or more, more preferably 0.2 or more, even more preferably 0.3 or more, and still more preferably 0.4 or more, from the viewpoint of making it easier to obtain good heat resistance.
From the viewpoint of making it easier to obtain good moldability, the ratio [layer A/layer B] is preferably 10 or less, more preferably 5 or less, even more preferably 3 or less, and even more preferably 2.5 or less.
From the above viewpoint, the ratio [layer A/layer B] is preferably 0.1 to 10, more preferably 0.2 to 5, even more preferably 0.3 to 3, and still more preferably 0.4 to 2.5.

In the laminate of the present invention, the ratio of the total thickness of layers A to the total thickness of layers B [total thickness of layers A/total thickness of layers B] is preferably 0.1 or more, more preferably 0.4 or more, even more preferably 0.6 or more, and still more preferably 0.8 or more, from the viewpoint of making it easier to obtain good heat resistance.
Furthermore, from the viewpoint of making it easier to obtain good moldability, the ratio [total thickness of layer A/total thickness of layer B] is preferably 10 or less, more preferably 8 or less, even more preferably 6 or less, and even more preferably 5 or less.
From the above viewpoint, the ratio [total thickness of layer A/total thickness of layer B] is preferably 0.1 to 10, more preferably 0.4 to 8, even more preferably 0.6 to 6, and still more preferably 0.8 to 5.

From the viewpoint of more easily achieving good heat resistance and moldability, the ratio of the total thickness of Layer A and Layer B to the overall thickness (100%) of the laminate of the present invention is preferably 80-100%, more preferably 85-100%, even more preferably 90-100%, even more preferably 95-100%, and may even be 100%.

The thickness of the entire laminate of the present invention is preferably 10 μm or more, more preferably 20 μm or more, even more preferably 30 μm or more, and still more preferably 40 μm or more, from the viewpoint of more easily obtaining high rigidity.
Furthermore, from the viewpoint of more easily obtaining high flexibility, the thickness of the entire laminate of the present invention is preferably 1,000 μm or less, more preferably 500 μm or less, even more preferably 300 μm or less, and even more preferably 100 μm or less.
From the above viewpoint, the thickness of the entire laminate of the present invention is preferably 10 to 1,000 μm, more preferably 20 to 500 μm, even more preferably 30 to 300 μm, and still more preferably 40 to 100 μm.
The thickness of the laminate can be measured by the method described in the examples below.

Next, we will explain layers A and B in detail.

<A layer>
The layer A is formed from a first resin composition.
That is, the layer A is formed by molding the first resin composition into a layer.
The content of P3MB in the first resin composition is 10 to 100% by mass relative to 100% by mass of the total amount of resin components in the first resin composition.
When the content of P3MB in the first resin composition is 10% by mass or more, good heat resistance can be obtained. From this viewpoint, the content of P3MB in the first resin composition is preferably 20 to 100% by mass, more preferably 40 to 100% by mass, even more preferably 60 to 100% by mass, still more preferably 70 to 100% by mass, even more preferably 80 to 100% by mass, still more preferably 90 to 100% by mass, and may even be 100% by mass, based on 100% by mass of the total amount of resin components in the first resin composition.
The content of P3MB in the first resin composition may be 90% by mass or less, or 80% by mass or less, relative to 100% by mass of the total amount of resin components in the first resin composition.
In the present invention, the term "resin component" means a polymer.

The content of the polypropylene resin in the first resin composition is 0 to 90% by mass relative to 100% by mass of the total amount of the resin components in the first resin composition.
When the content of the polypropylene-based resin in the first resin composition is 90% by mass or less, good heat resistance can be obtained. From this viewpoint, the content of the polypropylene-based resin in the first resin composition is preferably 0 to 80% by mass, more preferably 0 to 60% by mass, even more preferably 0 to 40% by mass, still more preferably 0 to 30% by mass, still more preferably 0 to 20% by mass, even more preferably 0 to 10% by mass, and may even be 0% by mass, based on 100% by mass of the total amount of resin components in the first resin composition.
Furthermore, the content of the polypropylene-based resin in the first resin composition may be 10% by mass or more, or 20% by mass or more, based on 100% by mass of the total amount of resin components in the first resin composition.

When the first resin composition contains a polypropylene-based resin, the total content of P3MB and the polypropylene-based resin in the first resin composition is, from the viewpoint of more easily obtaining good heat resistance and moldability, preferably 50.0 to 100 mass%, more preferably 60.0 to 100 mass%, even more preferably 70.0 to 100 mass%, still more preferably 80.0 to 100 mass%, still more preferably 90.0 to 100 mass%, still more preferably 95.0 to 100 mass%, and may even be 100 mass%, based on 100 mass% of the total amount of resin components in the first resin composition.
Resin compositions containing P3MB and polypropylene resins exhibit good heat resistance and moldability, which is presumably due in part to the fact that the P3MB and polypropylene resins have adequate miscibility, allowing the characteristics of both materials to be well expressed.

(Alkyl radical scavenger)
The first resin composition preferably contains an alkyl radical scavenger. By containing an alkyl radical scavenger, good heat resistance and moldability can be more easily obtained. This is also preferred from the viewpoint of further improving the flatness and yellowness index (YI) of the resulting laminate.
As used herein, the term "alkyl radical scavenger" refers to a compound that reacts with an alkyl radical derived from P3MB and stabilizes the alkyl radical. By stabilizing the alkyl radical, the compound suppresses a chain reaction of carbon-carbon bond dissociation reactions initiated by the alkyl radical.
The first resin composition preferably contains, as an alkyl radical scavenger, at least one compound selected from the group consisting of an acrylic phenol compound and a benzofuranone compound.
The alkyl radical scavengers may be used alone or in combination of two or more.

(Acrylphenol compound)
As the acrylic phenol compound, for example, a compound represented by the following general formula (I) can be used.

In general formula (I), R ¹ represents a hydrogen atom or a methyl group, R ² represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and R ³ , R ⁴ , R ⁵ and R ⁶ each independently represent an alkyl group having 1 to 9 carbon atoms.
Examples of the alkyl group having 1 to 3 carbon atoms include a methyl group, an ethyl group, an n-propyl group, and an isopropyl group.
The alkyl group having 1 to 9 carbon atoms may be linear or branched.
Examples of the alkyl group having 1 to 9 carbon atoms include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, an s-butyl group, a t-butyl group, a 1,1-dimethylpropyl group, a 1,2-dimethylpropyl group, a 2,2-dimethylpropyl group, a 1-methylbutyl group, a 2-methylbutyl group, a 3-methylbutyl group, an n-pentyl group, an n-hexyl group, an n-heptyl group, an n-octyl group, and an n-nonyl group.
^R1 is preferably a hydrogen atom.
^R2 is preferably a hydrogen atom or a methyl group, more preferably a methyl group.
R ³ , R ⁴ , R ⁵ and R ⁶ are each independently preferably an alkyl group having 3 to 8 carbon atoms, more preferably an alkyl group having 5 carbon atoms, and even more preferably a 1,1-dimethylpropyl group.

Examples of the acrylic phenol compound represented by general formula (I) include 2,4-di-t-amyl-6-[1-(3,5-di-t-amyl-2-hydroxyphenyl)ethyl]phenyl acrylate, 2,4-di-t-butyl-6-[1-(3,5-di-t-butyl-2-hydroxyphenyl)ethyl]phenyl acrylate, and 2-t-butyl-6-[(3-t-butyl-2-hydroxy-5-methylphenyl)methyl]-4-methylphenyl acrylate.
Commercially available alkyl radical scavengers may be used, and examples of the acrylic phenol compound represented by general formula (I) include those available under the trade names "Sumilizer (registered trademark) GS" and "Sumilizer (registered trademark) GM" manufactured by Sumitomo Chemical Co., Ltd.

(Benzofurano compounds)
As the benzofuranone compound, for example, a compound represented by the following general formula (II) can be used.

In general formula (II), R ⁷ and R ⁸ each independently represent an alkyl group having 1 to 4 carbon atoms, and R ⁹ and R ¹⁰ each independently represent an alkyl group having 1 to 9 carbon atoms.
Examples of the alkyl group having 1 to 4 carbon atoms include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, an s-butyl group, and a t-butyl group.
The alkyl group having 1 to 9 carbon atoms may be linear or branched.
Examples of the alkyl group having 1 to 9 carbon atoms include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, an s-butyl group, a t-butyl group, a 1,1-dimethylpropyl group, a 1,2-dimethylpropyl group, a 2,2-dimethylpropyl group, a 1-methylbutyl group, a 2-methylbutyl group, a 3-methylbutyl group, an n-pentyl group, an n-hexyl group, an n-heptyl group, an n-octyl group, and an n-nonyl group.
R ⁷ and R ⁸ are each independently preferably an alkyl group having 1 to 3 carbon atoms, more preferably a methyl group.
R ⁹ and R ¹⁰ are each independently preferably an alkyl group having 1 to 4 carbon atoms, more preferably a t-butyl group.

Examples of the benzofuranone compound represented by general formula (II) include 5,7-di-t-butyl-3-(3,4-di-methyl-phenyl)-3H-benzofuran-2-one, 5,7-di(t-butyl)-3-(3,4-di-propyl-phenyl)-3H-benzofuran-2-one, and 4-t-butyl-2-(5-t-butyl-2-oxo-3H-benzofuran-3-yl)phenyl-3,5-di-t-butyl-4-hydroxybenzoate.
Commercially available alkyl radical scavengers may be used, and examples of the benzofuranone compound represented by general formula (II) include "Irganox (registered trademark) HP-136" manufactured by BASF and "Revonox 501" manufactured by Chitec.

From the viewpoint of making it easier to achieve the effects of the present invention, the content of the alkyl radical scavenger in the first resin composition is preferably 0.01 to 1.00 parts by mass, more preferably 0.02 to 0.80 parts by mass, and even more preferably 0.05 to 0.70 parts by mass, relative to 100 parts by mass of the total amount of the resin components in the first resin composition.
When the first resin composition contains two or more types of alkyl radical scavengers, the content of the alkyl radical scavengers means the total content of the alkyl radical scavengers.

(antioxidant)
The first resin composition preferably further contains an antioxidant. By containing an antioxidant, good heat resistance and moldability can be more easily obtained. This is also preferable from the viewpoint of further improving the flatness and yellowness index (YI) of the resulting laminate.
The antioxidant is preferably at least one selected from the group consisting of phenol-based antioxidants and phosphorus-based antioxidants.
The antioxidants may be used alone or in combination of two or more.
In this specification, an antioxidant that also acts as an alkyl radical scavenger is considered to be an alkyl radical scavenger.

[Phenol-based antioxidants]
Examples of phenolic antioxidants include pentaerythritol tetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], 1,3,5-tris(3,5-di-t-butyl-4-hydroxybenzyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione, 1,3,5-tris[(4-t-butyl-3-hydroxy-2,6-xylyl)methyl]-1,3,5-triazine-2,4,6(1H,3H,5H)-trione, and o octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate, thiodiethylene-bis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], N,N'-hexane-1,6-diylbis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionamide], 3,3',3'',5,5',5''-hexa-t-butyl-α,α',α''-(mesitylene-2,4,6-triyl)tri-p-cresol, ethylenediamine bis(oxyethylene)bis[3-(5-t-butyl-4-hydroxy-m-tolyl)propionate], hexamethylene-bis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], 2,6-di-t-butyl-4-[4,6-bis(octylthio)-1,3,5-triazin-2-ylamino]phenol, 3,9-bis[2-(3-(3-t-butyl-4-hydroxy-5-methylphenyl)propionyloxy)-1,1-dimethylethyl]-2, Examples include 4,8,10-tetraoxaspiro(5,5)undecane, 4,4',4''-(1-methylpropanyl-3-ylidene)tris(6-t-butyl-m-cresol), 6,6'-di-t-butyl-4,4'-butylidene-m-cresol, octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate, and benzenepropionic acid 3,5-bis-(1,1-dimethylethyl)-4-hydroxy-C7-C9 branched alkyl ester.

Commercially available phenolic antioxidants may be used, such as the "ADEKA STAB (registered trademark) AO series" manufactured by ADEKA Corporation and the "Irganox (registered trademark) series" manufactured by BASF Japan Ltd.

[Phosphorus-based antioxidants]
Examples of phosphorus-based antioxidants include 3,9-bis(2,6-di-t-butyl-4-methylphenoxy)-2,4,8,10-tetraoxa-3,9-diphosphaspiro[5.5]undecane, tetrakis(2,4-di-t-butyl-phenyl)-4,4'-biphenylenephosphonite, 2,2-methylenebis(4,6-di-t-butylphenyl)octylphosphite, and tris(2,4-di-t-butylphenyl)phosphonite. phosphite, bis(2,4-bis(1,1-dimethylethyl)-6-methylphenyl)ethyl ester phosphite, bis(2,4-di-t-butylphenyl)pentaerythritol diphosphite, bis(2,4-dicumylphenyl)pentaerythritol diphosphite, di-t-butyl-m-cresyl-phosphonite, diethyl[(3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl)methyl]phosphite phosphonate, tris(2,4-di-t-butylphenyl)phosphite, tetrakis(2,4-di-t-butylphenyl)-4,4'-biphenylene diphosphonite, 3,9-bis(octadecyoxy)-2,4,8,10-tetraoxa-3,9-diphosphaspiro[5.5]undecane, tris(2,4-di-t-butylphenyl)phosphite, tris(nonylphenyl)phosphite, tetra-C12-15-alkyl Examples of suitable phosphite compounds include 2-ethylhexyl(propane-2,2-diylbis(4,1-phenylene))bis(phosphite), 2-ethylhexyldiphenyl phosphite, isodecyldiphenyl phosphite, trisisodecyl phosphite, triphenyl phosphite, and 3,9-bis[2,4-bis(1-methyl-1-phenylethyl)phenoxy]-2,4,8,10-tetraoxa-3,9-diphosphaspiro[5.5]undecane.

Commercially available phosphorus-based antioxidants may be used, such as the "ADK STAB (registered trademark) PEP series" and "ADK STAB (registered trademark) HP series" manufactured by ADEKA Corporation, the "Irgafos (registered trademark) series" manufactured by BASF Japan, and "HOSTANOX (registered trademark) P-EPQ" manufactured by Clariant.

[Other antioxidants]
The first resin composition may contain an antioxidant other than the phenolic antioxidant and the phosphorus-based antioxidant, as long as the effects of the present invention are achieved. Examples of the antioxidant other than the phenolic antioxidant and the phosphorus-based antioxidant include a sulfur-based antioxidant and an amine-based antioxidant.

From the viewpoint of making it easier to achieve the effects of the present invention, the content of the antioxidant in the first resin composition is preferably 0.01 parts by mass or more, and more preferably 0.10 parts by mass or more, per 100 parts by mass of the total amount of resin components in the first resin composition.
Furthermore, from the viewpoint of suppressing bleed-out and sublimation of the antioxidant, as well as from the viewpoint of economy, the content of the antioxidant in the first resin composition is preferably 1.00 parts by mass or less, and more preferably 0.80 parts by mass or less, relative to 100 parts by mass of the total amount of the resin components in the first resin composition.
From the above viewpoint, the content of the antioxidant in the first resin composition is preferably 0.01 to 1.00 parts by mass, and more preferably 0.10 to 0.80 parts by mass, relative to 100 parts by mass of the total amount of the resin components in the first resin composition.
When the first resin composition contains two or more kinds of antioxidants, the content of the antioxidants means the total content of the antioxidants.

(Other additives)
The first resin composition may contain additives other than the alkyl radical scavenger and the antioxidant, as long as the effects of the present invention are not impaired.
Examples of other additives include antacids, fillers, light stabilizers, antistatic agents, flame retardants, pigments, polymerization inhibitors, heavy metal deactivators, ultraviolet absorbers, nucleating agents, clarifying agents, lubricants, fluorescent brighteners, rust inhibitors, and sliding agents.
The other additives may be used alone or in combination of two or more.

[Antacids]
The first resin composition preferably contains an antacid from the viewpoint of suppressing deterioration due to acid components generated from residual metal components and the like during melt-kneading.
Antacids include barium laurate, calcium stearate, zinc stearate, magnesium stearate, aluminum stearate, zinc oleate, magnesium 12-hydroxystearate, and the like.
The antacids may be used alone or in combination of two or more.
When the first resin composition contains an antacid, the content of the antacid in the first resin composition can be determined appropriately, and may be, for example, 0.01 to 200 parts by mass, 0.01 to 100 parts by mass, 0.01 to 50 parts by mass, 0.01 to 10 parts by mass, 0.01 to 1.00 parts by mass, or 0.1 to 0.80 parts by mass, relative to 100 parts by mass of the total amount of the resin components in the first resin composition.

[Filler]
Examples of fillers include fibrous compounds such as glass fiber, alumina fiber, resin fiber, carbon fiber, and cellulose fiber; plate-like compounds such as mica, talc, montmorillonite, and plate-like aluminum; spherical compounds such as glass beads, shirasu balloons, and acrylic balloons; needle-like compounds such as acicular metal titanate, wollastonite, acicular silica, and tin oxide; and powdered compounds such as powdered metal titanate, finely divided wood chips, titanium oxide, calcium carbonate, silica, and alumina. These fillers may be surface-treated with, for example, a silane coupling agent. A compatibilizer may also be used to enhance the dispersibility of the filler.
The fillers may be used alone or in combination of two or more.
When the first resin composition contains a filler, the content of the filler in the first resin composition can be determined appropriately, and may be, for example, 0.01 to 300 parts by mass, or 0.1 to 100 parts by mass, relative to 100 parts by mass of the total amount of the resin components in the first resin composition.

From the viewpoint of more easily achieving good heat resistance and moldability, the total content of the resin components in the first resin composition is preferably 50.0 to 100% by mass, more preferably 60.0 to 99.9% by mass, even more preferably 70.0 to 99.8% by mass, even more preferably 80.0 to 99.7% by mass, even more preferably 90.0 to 99.6% by mass, and even more preferably 95.0 to 99.5% by mass, based on 100% by mass of the total amount of the first resin composition.

It is preferable that the first resin composition is substantially free of a thermosetting resin. Specifically, "substantially free" here means that the content of the thermosetting resin in 100% by mass of the first resin composition is 5.0% by mass or less, preferably 1.0% by mass or less, more preferably 0.1% by mass or less, even more preferably 0.05% by mass or less, and still more preferably 0.01% by mass or less.
In other words, the content of the thermosetting resin in the first resin composition is, relative to 100% by mass of the first resin composition, preferably 0 to 5.0% by mass, more preferably 0 to 1.0% by mass, even more preferably 0 to 0.1% by mass, still more preferably 0 to 0.05% by mass, still more preferably 0 to 0.01% by mass, and may be 0% by mass.

Preferably, the first resin composition is substantially free of cyclic polyolefins. Specifically, "substantially free" here means that the cyclic polyolefin content is 5.0% by mass or less, preferably 1.0% by mass or less, more preferably 0.1% by mass or less, even more preferably 0.05% by mass or less, and still more preferably 0.01% by mass or less, based on 100% by mass of the first resin composition.
In other words, the content of the cyclic polyolefin in the first resin composition is, relative to 100% by mass of the first resin composition, preferably 0 to 5.0% by mass, more preferably 0 to 1.0% by mass, even more preferably 0 to 0.1% by mass, still more preferably 0 to 0.05% by mass, even more preferably 0 to 0.01% by mass, and may be 0% by mass.
The "cyclic polyolefin" refers to a polymer having an alicyclic structure (cycloolefin skeleton) in its main chain, and containing structural units derived from a monomer capable of introducing the alicyclic structure into the main chain of the polymer in an amount of at least 10 mol % relative to the total amount (100 mol %) of structural units constituting the polymer.
The monomer capable of introducing the alicyclic structure into the main chain of the polymer is not particularly limited, and examples thereof include substituted or unsubstituted norbornene, substituted or unsubstituted tetracyclododecene, and substituted or unsubstituted dicyclopentadiene.
Examples of the cyclic polyolefin include a polymer obtained by subjecting a cyclic olefin monomer such as substituted or unsubstituted norbornene to ring-opening metathesis polymerization (ROMP) to obtain a ring-opening polymer, and then hydrogenating the double bonds in the polymer. Also included are copolymers obtained by addition polymerization of the cyclic olefin monomer with an olefin such as ethylene.
Examples of commercially available cyclic polyolefins include "ZEONEX (registered trademark)" and "ZEONOR (registered trademark)" manufactured by Zeon Corporation; "APEL (registered trademark)" manufactured by Mitsui Chemicals, Inc.; "ARTON (registered trademark)" manufactured by JSR Corporation; and "TOPAS (registered trademark)" manufactured by Topas Advanced Polymers GmbH.

(Method for producing first resin composition)
The first resin composition can be produced by blending and kneading P3MB and, if necessary, a polypropylene resin and other components, etc. The method for blending the components is not particularly limited as long as the effects of the present invention are achieved, and for example, a method of melt-kneading using a twin-screw kneading extruder can be used.
The conditions for obtaining the first resin composition by melt-kneading will be described below.

When the first resin composition is obtained by melt-kneading, the melt-kneading conditions are preferably such that the first resin composition is melt-kneaded in an inert atmosphere or in a low-oxygen state.
By melt-kneading in an inert atmosphere or a low-oxygen state, deterioration of the physical properties of the first resin composition due to oxygen can be suppressed, and good heat resistance and moldability can be more easily obtained. This is also preferable from the viewpoint of further improving the flatness and yellowness index (YI) of the obtained laminate.
Here, the "low-oxygen state" refers to a state in which the oxygen concentration inside the melt-kneader is lowered by degassing the inside of the melt-kneader under reduced pressure compared to before degassing. Furthermore, in the "inert atmosphere" state, an inert gas is injected into the melt-kneader, resulting in a state in which the oxygen concentration inside the melt-kneader is lowered compared to before the inert gas was injected. Therefore, the concept of "low-oxygen state" may also include a state of "under an inert atmosphere." In the "low-oxygen state," the oxygen concentration inside the melt-kneader is preferably 5% or less, more preferably 2% or less, and even more preferably 1% or less.
The oxygen concentration can be measured using a diaphragm-type galvanic oxygen meter, such as the "XP-3180E" (diaphragm-type galvanic cell type) manufactured by New Cosmos Electric Co., Ltd., or its successor, the "XP-3380II-E" (galvanic cell type).

The method of melt-kneading by injecting an inert gas into the melt-kneader may, for example, be to feed each component while injecting an inert gas into the melt-kneader and then melt-kneading; or to inject an inert gas after feeding each component into the melt-kneader, preferably before starting to heat or before starting shearing, more preferably before starting to heat and before starting shearing, and then melt-kneading; or to inject an inert gas into the melt-kneader, and then feed each component from a sealed supply section and melt-knead. Moreover, during melt-kneading, the inert gas may continue to be injected into the melt-kneader.
The method of injecting the inert gas can be carried out depending on the equipment provided in each melt kneader, and is not particularly limited. The inert gas may be injected, for example, from a gas supply section for inert gas or the like provided in the melt kneader, from a supply section for each component provided in the melt kneader, or from a gas vent provided in the melt kneader. The method of injecting the inert gas is preferably a method in which the inert gas is injected into the entire extruder from the inert gas supply section to the heating section where melt kneading is performed, thereby enabling melt kneading.
Examples of inert gases include nitrogen gas, helium gas, neon gas, argon gas, krypton gas, and carbon dioxide gas, with nitrogen gas being preferred from the viewpoints of availability and versatility.

The method of melt-kneading after degassing the inside of the melt-kneader under reduced pressure may involve, for example, adding each component while degassing the inside of the melt-kneader under reduced pressure and then performing melt-kneading, or after adding each component into the melt-kneader, degassing the inside of the melt-kneader under reduced pressure and then performing melt-kneading, preferably before starting to raise the temperature or before starting shearing, more preferably before starting to raise the temperature and before starting shearing, or after degassing the inside of the melt-kneader under reduced pressure and then adding each component from a sealed supply part and performing melt-kneading. Moreover, during melt-kneading, degassing the inside of the melt-kneader under reduced pressure may be performed intermittently or continuously.
The method of degassing the inside of the melt kneader under reduced pressure can be carried out according to the equipment provided in each melt kneader, and for example, it may be carried out through a vacuum vent. For the degassing under reduced pressure, for example, a vacuum pump can be used.
There are no limitations on the method for degassing the inside of the melt-kneader under reduced pressure, as long as the melt-kneading can be carried out in an inert atmosphere or in a low-oxygen state.
When degassing under reduced pressure, the inside of the melt kneader can be made into a vacuum state of, for example, 0.1 to 50 kPa.

The melt-kneading machine can be a single-screw extruder, multi-screw extruder, kneader, Banbury mixer, or other machine equipped with equipment capable of melt-kneading by injecting an inert gas into the melt-kneading machine, or equipment capable of melt-kneading by depressurizing and degassing the inside of the melt-kneading machine.

The aforementioned injection of inert gas and degassing under reduced pressure may be used in combination. In this case, it is preferable to inject the inert gas upstream of the melt kneader before the raw materials are added or together with the raw materials, while carrying out degassing under reduced pressure further downstream. It is also more preferable to inject the inert gas upstream of the melt kneader before the raw materials are added or together with the raw materials, while carrying out degassing under reduced pressure further downstream, and to continue both the injection of inert gas and degassing under reduced pressure during melt kneading.

The temperature during melt-kneading is preferably 280 to 323°C.
If the temperature during melt-kneading is 280°C or higher, P3MB can be sufficiently melted, and the aforementioned additives can be easily dispersed in the resin component. From this viewpoint, the temperature during melt-kneading is more preferably 285°C or higher, even more preferably 290°C or higher, and even more preferably 292°C or higher.
Furthermore, when the temperature during melt-kneading is 323°C or less, decomposition of each component can be suppressed, and good heat resistance and moldability can be more easily obtained, and the flatness and yellowness index (YI) of the obtained laminate can be further improved. From these viewpoints, the temperature during melt-kneading is more preferably 315°C or less, even more preferably 305°C or less, still more preferably 300°C or less, and still more preferably 298°C or less.
From the above viewpoint, the temperature during melt-kneading is more preferably 285 to 315°C, even more preferably 290 to 305°C, still more preferably 290 to 300°C, and even more preferably 292 to 298°C.

<B layer>
The layer B is formed from a second resin composition.
That is, the layer B is formed by molding the second resin composition into a layer.
The content of P3MB in the second resin composition is 0 to 90% by mass relative to 100% by mass of the total amount of resin components in the second resin composition.
When the content of P3MB in the second resin composition is 90% by mass or less, good moldability can be obtained. From this viewpoint, the content of P3MB in the second resin composition is preferably 0 to 80% by mass, more preferably 0 to 60% by mass, even more preferably 0 to 40% by mass, still more preferably 0 to 30% by mass, still more preferably 0 to 20% by mass, even more preferably 0 to 10% by mass, and may even be 0% by mass, based on 100% by mass of the total amount of resin components in the second resin composition.
The content of P3MB in the second resin composition may be 10% by mass or more, or 20% by mass or more, relative to 100% by mass of the total amount of resin components in the second resin composition.

The content of the polypropylene resin in the second resin composition is 10 to 100% by mass relative to 100% by mass of the total amount of the resin components in the second resin composition.
When the content of the polypropylene-based resin in the second resin composition is 10% by mass or more, good moldability can be obtained. From this viewpoint, the content of the polypropylene-based resin in the second resin composition is preferably 20 to 100% by mass, more preferably 40 to 100% by mass, even more preferably 60 to 100% by mass, still more preferably 70 to 100% by mass, even more preferably 80 to 100% by mass, still more preferably 90 to 100% by mass, and may even be 100% by mass, based on 100% by mass of the total amount of resin components in the second resin composition.
Furthermore, the content of the polypropylene-based resin in the second resin composition may be 90% by mass or less, or 80% by mass or less, based on 100% by mass of the total amount of resin components in the second resin composition.

When the second resin composition contains P3MB, the total content of P3MB and polypropylene resin in the second resin composition is, from the viewpoint of more easily achieving good heat resistance and moldability, preferably 50.0 to 100% by mass, more preferably 60.0 to 100% by mass, even more preferably 70.0 to 100% by mass, even more preferably 80.0 to 100% by mass, even more preferably 90.0 to 100% by mass, even more preferably 95.0 to 100% by mass, and may even be 100% by mass, based on 100% by mass of the total amount of resin components in the second resin composition.

The second resin composition may or may not contain the alkyl radical scavenger, antioxidant, other additives, etc. that the first resin composition may contain.
When the second resin composition contains an alkyl radical scavenger, an antioxidant, or other additives, the content of these components is the same as the content of these components in the first resin composition.

From the viewpoint of more easily achieving good heat resistance and moldability, the total content of the resin components in the second resin composition is preferably 50.0 to 100% by mass, more preferably 60.0 to 99.9% by mass, even more preferably 70.0 to 99.8% by mass, even more preferably 80.0 to 99.7% by mass, even more preferably 90.0 to 99.6% by mass, and even more preferably 95.0 to 99.5% by mass, based on 100% by mass of the total amount of the second resin composition.

Preferably, the second resin composition is substantially free of a thermosetting resin. Specifically, "substantially free" here means that the content of the thermosetting resin in 100% by mass of the second resin composition is 5.0% by mass or less, preferably 1.0% by mass or less, more preferably 0.1% by mass or less, even more preferably 0.05% by mass or less, and still more preferably 0.01% by mass or less.
In other words, the content of the thermosetting resin in the second resin composition is, relative to 100% by mass of the second resin composition, preferably 0 to 5.0% by mass, more preferably 0 to 1.0% by mass, even more preferably 0 to 0.1% by mass, still more preferably 0 to 0.05% by mass, still more preferably 0 to 0.01% by mass, and may even be 0% by mass.

The second resin composition is preferably substantially free of the cyclic polyolefin. Specifically, "substantially free" here means that the cyclic polyolefin content is 5.0% by mass or less, preferably 1.0% by mass or less, more preferably 0.1% by mass or less, even more preferably 0.05% by mass or less, and still more preferably 0.01% by mass or less, based on 100% by mass of the second resin composition.
In other words, the content of the cyclic polyolefin in the second resin composition is, relative to 100% by mass of the second resin composition, preferably 0 to 5.0% by mass, more preferably 0 to 1.0% by mass, even more preferably 0 to 0.1% by mass, still more preferably 0 to 0.05% by mass, even more preferably 0 to 0.01% by mass, and may even be 0% by mass.

(Method for producing second resin composition)
The second resin composition can be produced by blending and kneading a polypropylene resin, and, if necessary, P3MB and other components.
The method for producing the second resin composition is described in the above section "(Method for producing first resin composition)" by replacing "first resin composition" with "second resin composition." However, the method for producing the second resin composition is not limited to the method described in the above section "(Method for producing first resin composition)." For example, if the second resin composition does not contain P3MB, it may be produced by a known method of melt-kneading a polypropylene resin.

<Difference in P3MB content>
In the laminate of the present invention, the content of P3MB by mass in the first resin composition relative to 100% by mass of the total amount of resin components is greater than the content of P3MB by mass in the second resin composition relative to 100% by mass of the total amount of resin components.
The difference between the mass-based P3MB content in the first resin composition (hereinafter referred to as the "P3MB content in the first resin composition") and the mass-based P3MB content in the second resin composition (hereinafter referred to as the "P3MB content in the second resin composition") (hereinafter referred to as the "P3MB content in the second resin composition") is preferably 10 to 100 mass%, more preferably 20 to 100 mass%, even more preferably 35 to 100 mass%, still more preferably 45 to 100 mass%, still more preferably 60 to 100 mass%, still more preferably 80 to 100 mass%, and still more preferably 90 to 100 mass%, from the viewpoint of more easily obtaining good heat resistance and moldability.

<Yellowness (YI)>
The yellowness index (YI) of the laminate of the present invention is preferably 3.50 or less, more preferably 2.80 or less, even more preferably 2.40 or less, still more preferably 2.00 or less, still more preferably 1.40 or less, still more preferably 1.00 or less, still more preferably 0.80 or less, and still more preferably 0.50 or less. There is no particular restriction on the lower limit of the yellowness index (YI), but it is preferably, for example, 0.00.
In other words, the yellowness index (YI) of the laminate of the present invention is preferably 0.00 to 3.50, more preferably 0.00 to 2.80, even more preferably 0.00 to 2.40, still more preferably 0.00 to 2.00, still more preferably 0.00 to 1.40, still more preferably 0.00 to 1.00, still more preferably 0.00 to 0.80, and still more preferably 0.00 to 0.50.
The yellowness index (YI) of the laminate of the present invention can be measured by the method described in the examples below.

<Coefficient of linear expansion>
From the viewpoint of heat resistance, the absolute value of the linear expansion coefficient of the laminate of the present invention at 160 to 260°C is preferably 2,000 ppm/°C or less, more preferably 1,500 ppm/°C or less, even more preferably 1,300 ppm/°C or less, still more preferably 1,000 ppm/°C or less, and still more preferably 700 ppm/°C or less.
In addition, when the absolute value of the linear expansion coefficient of the resin composition of the present invention at 160 to 260°C cannot be measured due to melting of the resin composition, but the absolute value of the linear expansion coefficient at 160 to 240°C can be measured, the absolute value of the linear expansion coefficient at 160 to 240°C is preferably 3,500 ppm/°C or less, more preferably 3,000 ppm/°C or less, even more preferably 2,500 ppm/°C or less, and still more preferably 2,000 ppm/°C or less.
The absolute value of the linear expansion coefficient at 160 to 260° C. and the absolute value of the linear expansion coefficient at 160 to 240° C. of the laminate of the present invention can be measured by the method described in the examples below.

<Recycled raw materials>
The laminate of the present invention preferably contains recycled raw materials.
The term "recycled raw materials" refers to recycled raw materials recovered during the process of producing the laminate of the present invention. Specific examples include non-product parts such as film scraps and film edges generated during the process of producing the laminate of the present invention; non-standard products; and the like, which can be crushed and used as needed. The inclusion of recycled raw materials contributes to resource conservation, reduces fusion of raw materials in the process before being fed into the extruder, and improves extrusion stability during film formation by better dispersing the raw materials. As a result, thickness unevenness of the resulting laminate is suppressed, and the quality of the laminate is improved, thereby improving moldability and post-processability.
The laminate of the present invention may contain recycled materials and one or more selected from the group consisting of non-recycled P3MB and non-recycled polypropylene-based resins. In this case, for example, by appropriately adjusting the amount of non-recycled P3MB and non-recycled polypropylene-based resins in accordance with the composition and amount of the recycled materials used, the content of P3MB and polypropylene-based resin in the resin composition constituting the laminate can be adjusted to fall within the content ranges described above in the <Layer A> and <Layer B> sections.
The content of the recycled raw materials in the laminate of the present invention may be 1 to 100% by mass, 10 to 90% by mass, 20 to 80% by mass, or 30 to 70% by mass.

The shape of the laminate of the present invention is not particularly limited, and examples include a film, plate, rod, strip, tube, cylinder, hollow body, etc. Among these, the laminate of the present invention is preferably a film. Hereinafter, a film, which is one embodiment of the laminate of the present invention, may be referred to as a "multilayer film."

(Film curl degree)
The curl degree of the film, which is one embodiment of the laminate of the present invention, is preferably 26.0 mm or less, more preferably 22.0 mm or less, even more preferably 18.0 mm or less, still more preferably 14.0 mm or less, still more preferably 10.0 mm or less, still more preferably 6.0 mm or less, and still more preferably 2.0 mm or less. There is no particular restriction on the lower limit of the curl degree, but it is preferably 0 mm, for example.
The curl degree of the film is preferably 0 to 26.0 mm, more preferably 0 to 22.0 mm, even more preferably 0 to 18.0 mm, still more preferably 0 to 14.0 mm, still more preferably 0 to 10.0 mm, still more preferably 0 to 6.0 mm, and still more preferably 0 to 2.0 mm.
The degree of curl for evaluating the flatness of the film can be measured by the method described in the examples below.

<Applications of the laminate>
The laminate of the present invention has good moldability and heat resistance and can be used in a variety of applications. The applications of the laminate of the present invention are not particularly limited, but the laminate can be suitably used for, for example, films, sheets, fibers, electrical and electronic devices, home appliance parts, office automation equipment, information terminal equipment, machine parts, automotive materials, building materials, civil engineering materials, fishery materials, various containers, lighting equipment, etc.
Examples of the film include films for film capacitors, films for high-frequency circuit substrates, films for transparent substrates, insulating films, films for thermoforming, packaging films, optical films, films for surface protection, films for processing, films for release, films for sanitary materials, films for agriculture, films for construction, and films for medical use.

[Method of manufacturing laminate]
The method for producing a laminate of the present invention is a method for producing a laminate, which includes a step (I) of melt-extruding a first resin composition.

<Step (I)>
Step (I) is a step of melt-extruding the first resin composition. As a method for melt-extruding the first resin composition, an extruder is preferably used, from the viewpoint of facilitating production of a laminate with excellent dimensional accuracy. As the extruder, for example, a single-screw extruder or a multi-screw extruder such as a twin-screw kneading extruder can be used. From the viewpoint of sufficiently melt-kneading each component, a multi-screw extruder such as a twin-screw kneading extruder is preferably used.

In step (I), the first resin composition is preferably melted in an inert atmosphere or in a low-oxygen state, more preferably in an inert atmosphere.
By melting the first resin composition in an inert atmosphere or in a low-oxygen state, deterioration of the physical properties of the first resin composition due to oxygen can be suppressed, making it easier to obtain good heat resistance and moldability, and is also preferable from the viewpoint of further improving the flatness and yellowness index (YI) of the laminate.
For example, when an extruder is used in step (I), it is preferable to melt the first resin composition using at least one method selected from the group consisting of injecting an inert gas into the extruder to melt the first composition, and degassing the inside of a melt kneader under reduced pressure to melt the first resin composition.

Examples of the method of injecting an inert gas into the extruder to melt the first resin composition include a method in which, while injecting an inert gas into the extruder, the first resin composition prepared in advance by the method described above in the section "Method for producing first resin composition" is fed into a raw material inlet such as a hopper, and the first resin composition is melted in the extruder; or a method in which, after the first resin composition is fed into the extruder from a raw material inlet such as a hopper, an inert gas is injected, preferably before starting to increase the temperature or before starting to shear, more preferably before starting to increase the temperature and before starting to shear, and then the first resin composition is melted in the extruder.
In addition, an inert gas may be continuously injected into the extruder while the first resin composition is melted, and it is preferable to continue injecting an inert gas into the extruder while the first resin composition is melted.
The method of injecting the inert gas can be carried out depending on the equipment of the extruder used, and is not particularly limited. The inert gas may be injected, for example, from a gas supply section such as an inert gas provided in the extruder, or from a supply section of each component such as a hopper provided in the extruder. The method of injecting the inert gas is preferably a method in which the inert gas is injected into the entire extruder from the inert gas supply section to the heating section where melt-kneading is performed, thereby enabling melt-kneading.
Examples of the inert gas include nitrogen gas, helium gas, neon gas, argon gas, krypton gas, and carbon dioxide gas, and nitrogen gas is preferred from the viewpoints of availability and versatility.

Examples of the method of melting the first resin composition by degassing the inside of the extruder under reduced pressure include a method of feeding the first resin composition, which has been prepared in advance by the method described above in the section "Method for producing first resin composition," into a raw material inlet such as a hopper and melting it while degassing the inside of the extruder under reduced pressure; or a method of feeding the first resin composition into the extruder through a raw material inlet such as a hopper, and then degassing the inside of the extruder under reduced pressure and melting it, preferably before starting to heat the extruder or before starting to shear the extruder, more preferably before starting to heat the extruder and before starting to shear the extruder.
Furthermore, while the first resin composition is being melted, the degassing under reduced pressure inside the extruder may be carried out intermittently or continuously, and it is preferable to carry out the degassing under reduced pressure continuously while the first resin composition is being melted.
The degassing method for the inside of the extruder is not limited as long as the first resin composition can be melt-kneaded in an inert atmosphere or a low-oxygen state. For example, in one embodiment of the production method, the degassing method for the inside of the extruder can be performed according to the equipment provided in the extruder used, and may be performed, for example, through a vacuum vent. For example, a decompression pump such as a vacuum pump can be used for the degassing method.
Furthermore, by performing degassing under reduced pressure inside the extruder, it is possible to remove moisture remaining in the first resin composition and organic solvents that vaporize at the melting temperature, etc., and therefore it is possible to suppress foaming of the molten material caused by moisture, etc. when the molten material is extruded from a T-die, etc., which is preferable. From this viewpoint, the degassing under reduced pressure is preferably performed after the first resin composition is melted and before it is extruded, and may be performed, for example, from a vent provided in a barrel corresponding to the position of the shearing section of the extruder.

The aforementioned injection of inert gas and degassing under reduced pressure may be used in combination. In this case, it is preferable to inject the inert gas upstream of the extruder before or together with the raw materials, while carrying out degassing under reduced pressure further downstream. It is more preferable to continue both the injection of inert gas and degassing under reduced pressure during melt-kneading.

Furthermore, as described above, the first resin composition used in step (I) may be a first resin composition prepared in advance by the method described above in the section "Method for producing first resin composition," or a method may be used in which, for example, a twin-screw kneading extruder is used as the extruder during step (I), the components described above are kneaded in the extruder to prepare the first resin composition, and the molten first resin composition is then directly extruded from the extruder.

In step (I), the first resin composition is preferably melted at 280 to 323°C.
In step (I), when the temperature during melt-kneading is 280°C or higher, the first resin composition can be sufficiently melted and good moldability can be obtained. From this viewpoint, the temperature during melt-kneading in step (I) is more preferably 285°C or higher, even more preferably 290°C or higher, and still more preferably 292°C or higher.
Furthermore, when the temperature during melt-kneading is 323°C or less, thermal decomposition of each component can be suppressed. Furthermore, good heat resistance and moldability can be more easily obtained, and the flatness and yellowness index (YI) of the laminate can also be further improved. From these viewpoints, the temperature during melt-kneading in step (I) is more preferably 315°C or less, even more preferably 305°C or less, still more preferably 300°C or less, and even more preferably 298°C or less.
From the above viewpoints, the temperature during melt-kneading in step (I) is more preferably 285 to 315°C, even more preferably 290 to 305°C, still more preferably 290 to 300°C, and still more preferably 292 to 298°C.

In step (I), after the first resin composition is melted, the first resin composition is extruded, for example, from a die attached to the tip of an extruder, and then cooled.
The die is not particularly limited and may be appropriately selected depending on the configuration of the desired laminate. When producing a film, it is preferable to use a T-die, from the viewpoint of facilitating production and making it easier to obtain a film with excellent dimensional accuracy.
The cooling method is not particularly limited, but it is preferable to cool the mixture using a casting drum as shown in the following step (II).

<Step (II)>
The production method preferably includes a step (II) of solidifying the molten extrudate of the first resin composition obtained in the step (I) using a casting drum.
The temperature of the casting drum is not particularly limited, but is preferably 40 to 250°C.
When the temperature of the casting drum is 40° C. or higher, good heat resistance and moldability can be more easily obtained, and the flatness and yellowness index (YI) of the laminate can be further improved. From these viewpoints, the temperature of the casting drum is more preferably 50° C. or higher, even more preferably 60° C. or higher, still more preferably 80° C. or higher, still more preferably 100° C. or higher, still more preferably 120° C. or higher, still more preferably 125° C. or higher, still more preferably 130° C. or higher, and still more preferably 135° C. or higher.
Furthermore, by setting the temperature of the casting drum to 250° C. or less, the molten extrudate can be prevented from fusing to the casting drum. From this viewpoint, the temperature of the casting drum is preferably 250° C. or less, more preferably 240° C. or less, even more preferably 230° C. or less, still more preferably 220° C. or less, still more preferably 210° C. or less, still more preferably 205° C. or less, still more preferably 200° C. or less, and still more preferably 190° C. or less.
From the above viewpoints, the temperature of the casting drum in step (II) is more preferably 50 to 240°C, even more preferably 60 to 230°C, still more preferably 80 to 220°C, still more preferably 100 to 210°C, still more preferably 120 to 210°C, still more preferably 125 to 205°C, still more preferably 130 to 200°C, and still more preferably 135 to 190°C.
Here, the "temperature of the casting drum" refers to the temperature of the surface of the casting drum.

The molded body solidified by cooling after step (II) may then be wound into a roll using a winding machine or the like, if necessary. Furthermore, if necessary, it may be further stretched using a stretching machine or the like.

The laminate of the present invention can be produced by laminating a molded body made of a first resin composition produced through steps (I) and (II) with a molded body made of a second resin composition produced separately.
The laminate of the present invention can also be produced by co-extruding the melt of the second resin composition and the melt of the first resin composition through a T-die in the step (I).

A draft ratio [Tt/Ft], which is the ratio of the gap thickness (Tt) of the lip portion of the T-die to the thickness (Ft) of the laminate formed by coextrusion from the lip portion, is preferably 1 to 30.
When the draft ratio [Tt/Ft] is 1 or more, good heat resistance and formability are more easily obtained, and the flatness and yellowness index (YI) of the film are also more excellent. From these viewpoints, the draft ratio [Tt/Ft] is more preferably 2 or more, even more preferably 3 or more, still more preferably 4 or more, and still more preferably 5 or more.
Furthermore, when the draft ratio [Tt/Ft] is 30 or less, breakage of the film during film formation and post-processing can be prevented. Furthermore, thickness unevenness of the film can be more easily suppressed, and shrinkage during thermoforming of the film can be more easily suppressed. From these viewpoints, the draft ratio [Tt/Ft] is more preferably 28 or less, even more preferably 25 or less, still more preferably 20 or less, even more preferably 15 or less, and still more preferably 10 or less.
From the above viewpoints, the draft ratio [Tt/Ft] is more preferably 2 to 28, even more preferably 2 to 25, still more preferably 3 to 20, still more preferably 4 to 15, and still more preferably 5 to 10.

When the melt of the second resin composition and the melt of the first resin composition are co-extruded through a T-die, the method of melt-extruding the second resin composition is explained in the explanation of the "<Step (I)>" section above, with "first resin composition" read as "second resin composition."
However, the method for melt-extruding the second resin composition is not limited to the method described in the section "<Step (I)>" above. For example, when the second resin composition does not contain P3MB, known melt-extrusion conditions for polypropylene-based resins may be adopted.
The die used for coextrusion may be appropriately selected from known coextrusion dies depending on the desired layer structure.

The method for manufacturing a laminate of the present invention may further include a step of molding the laminate obtained through the above steps. Examples of molding in this step include molding the laminate obtained through the above steps into a desired shape by stretching, compression molding, pressure forming, vacuum forming, etc.

The following examples will explain this embodiment in more detail, but the embodiment is not limited to these examples.

The physical properties of the P3MB obtained in Production Example 1 were measured or evaluated using the following methods.

[Content of structural units derived from comonomer (1-decene)]
The content of structural units derived from 1-decene in the P3MB obtained in Production Example 1 was determined as follows by IR measurement using an FT-IR analyzer ("Cary 600 series FTIR spectrometer" manufactured by Agilent Technologies) by the ATR method.
3-methyl-1-butene homopolymer and 1-decene homopolymer were mixed in arbitrary proportions, and a calibration curve was created from the ratio of the peak area at 1,461 cm ^-1 , which is the bending vibration derived from the main chain methylene group of each polymer, to the peak area at 727 cm ^-1 , which is the bending vibration derived from the side chain methylene group of 1-decene, and the mixing ratio of each resin. The IR measurement was performed on P3MB obtained in Production Example 1, and the obtained measured values were inserted into the calibration curve to determine the content ratio of structural units derived from 1-decene.

[Melting point]
Using a differential scanning calorimeter ("DSC25" manufactured by TA Instruments) the P3MB obtained in Production Example 1 was heated from 30°C to 320°C at a rate of 10°C/min under a nitrogen atmosphere (nitrogen flow rate 100 mL/min), held at 320°C for 5 minutes, and then cooled to -70°C at a rate of 10°C/min. After holding at -70°C for 5 minutes, the peak temperature was measured when the temperature was raised to 320°C at 10°C/min, and this temperature was taken as the melting point of P3MB.

[Melt viscosity]
The melt viscosity (Pa s) of the P3MB obtained in Production Example 1 was measured using a capillary rheometer ("Capilograph (registered trademark) 1C" manufactured by Toyo Seiki Seisaku-sho, Ltd.) under the conditions of a barrel temperature of 320°C and a shear rate of 100 sec ^-1 (capillary: inner diameter 1.0 mm × length 10 mm, extrusion rate 10 mm/min).

[Catalyst Preparation]
The catalyst component used in Production Example 1 was prepared by the following method.
(Preparation of Titanium Catalyst Component)
47.6 g (500 mmol) of anhydrous magnesium chloride, 250 ml of decane, and 234 ml (1.5 mol) of 2-ethylhexyl alcohol were heated at 130°C for 2 hours to produce a homogeneous solution. The resulting homogeneous solution was cooled to room temperature (23°C) and then added dropwise over 1 hour to 2 L (18 mol) of titanium tetrachloride maintained at -20°C to obtain a mixed solution. After completion of the dropwise addition of the homogeneous solution, the temperature of the resulting mixed solution was raised to 90°C over 2 hours. When the temperature reached 90°C, 11.4 mL (80 mmol) of ethyl benzoate was added and the mixture was maintained at the same temperature for 2 hours with stirring. After completion of the 2-hour reaction, the mixture was allowed to stand and the supernatant was removed. Decane and hexane were added, and the solids were washed three times. After that, the solids were resuspended in 2 L of titanium tetrachloride and again subjected to a heated reaction at 90°C for 2 hours. After the reaction was completed, the mixture was again left to stand, and the supernatant was repeatedly removed, followed by thorough washing with decane and hexane until no free titanium compound was detected in the washings. The resulting suspension was dried under reduced pressure at room temperature for 6 hours to obtain a titanium catalyst component.
The composition of the obtained titanium catalyst component was 4.0 mass % titanium, 56.0 mass % chlorine, 17.0 mass % magnesium, 10.4 mass % ethyl benzoate, and 12.6 mass % hydrocarbon solvent consisting of decane and hexane.

[Production Example 1]
(P3MB manufacturing)
A 20 L stainless steel autoclave was charged with 8.0 kg of 3-methyl-1-butene, 0.6 kg of 1-decene, 50 g of triethylaluminum diluted with hexane to a concentration of 1 mol/L, and 4 g of the titanium catalyst component prepared in the above "Catalyst Preparation," and the polymerization reaction was carried out at 70°C for 4 hours. During the polymerization reaction, hydrogen was continuously fed at a rate of 40 mL/min. After 4 hours, 200 g of 3-methyl-1-butanol was injected to stop the reaction and expel excess unreacted monomer. Next, 2 kg of normal heptane was introduced, and the mixture was stirred at 60°C for 30 minutes. The solids were then filtered off using a pressure filter. This procedure was repeated twice, and then the solvent was changed from 2 kg of normal heptane to 3 kg of 2-propanol, and the same procedure was repeated twice.
7.7 kg of the obtained crude polymer was placed in a 50 L vessel equipped with a stirrer, and then 8 kg of 1 mol/L hydrochloric acid and 16 kg of 2-propanol were added and stirred for 1 hour. This suspension was filtered by vacuum filtration and washed with 10 kg of 2-propanol. The crude polymer obtained from this first washing was placed in a 50 L vessel equipped with a stirrer, and then 20 kg of 2-propanol was added and stirred for 1 hour. This suspension was filtered by vacuum filtration and washed with 10 kg of 2-propanol. The obtained washed polymer was dried under reduced pressure at 80°C for 2 days to obtain 3.2 kg of P3MB, a copolymer of 3-methyl-1-butene and 1-decene.
The obtained P3MB was subjected to the above-mentioned measurements, and the melting point was found to be 286°C, the melt viscosity was 596 Pa s, and the content of structural units derived from the comonomer 1-decene in the P3MB was 1.1 mol%.

[Example 1]
(1) Preparation of First Resin Composition 100 parts by mass of P3MB (obtained in Production Example 1), 0.2 parts by mass of pentaerythritol tetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate] (antioxidant "ADK STAB (registered trademark) AO-60" manufactured by ADEKA Corporation), 0.2 parts by mass of 3,9-bis(2,6-di-t-butyl-4-methylphenoxy)-2,4,8,10-tetraoxa-3,9-diphosphaspiro[5.5]undecane (antioxidant "ADK STAB (registered trademark) PEP-36" manufactured by ADEKA Corporation), 2,4-di-t-amyl-6-[1-(3,5-di-t-amyl-2-hydroxyphenyl)ethyl]phenylacrylate After dry-blending 0.1 parts by mass of methylcellulose (an alkyl radical scavenger "Sumilizer (registered trademark) GS", manufactured by Sumitomo Chemical Co., Ltd.), and 0.25 parts by mass of zinc stearate (antacid), ...purging was performed using nitrogen with 99.99% purity from the raw material inlet as a measure to prevent oxygen from entering from the outside, and while eliminating oxygen as much as possible, the dry-blended materials were fed from the raw material inlet and brought into a molten state at a cylinder temperature of 295°C using a vented twin-screw kneading extruder "KZW15-45" (manufactured by Technovel Corporation), and the water was removed by vacuuming the shear zone of the extruder using a vacuum pump, thereby obtaining a pellet-shaped first resin composition (M1).

(2) Preparation of Second Resin Composition A pellet-shaped second resin composition (M2) was obtained in the same manner as in the above "(1) Production of First Resin Composition", except that in the above "(1) Production of First Resin Composition", "P3MB (obtained in Production Example 1)" was changed to "polypropylene (product name "Prime Polypro (registered trademark) PP E701G", MFR at 230°C measured in accordance with JIS K 7210:1999 = 0.5 g/10 min, manufactured by Prime Polymer Co., Ltd.)".

(3) Production of Multilayer Film (Laminate) The obtained pellet-shaped first resin composition (M1) and second resin composition (M2) were co-extruded under the following conditions to produce a film having a two-kind, three-layer structure of layer A/layer B/layer A (thickness ratio = 2:1:2) (total film thickness: 50 μm).
The extruders used to form Layer A and Layer B were vented twin-screw kneading extruders "KZW15-45" (manufactured by Technovel Co., Ltd.).
In each extruder, nitrogen purging was performed using 99.99% pure nitrogen from the raw material inlet as a measure to prevent oxygen from being mixed in from outside, and while eliminating oxygen as much as possible, the above-mentioned pellet-shaped first resin composition (M1) or second resin composition (M2) was fed into the raw material inlet and brought into a molten state at a cylinder temperature of 295°C.After that, moisture was removed by evacuating the shear section of the extruder using a vacuum pump, and three layers in the stacking order of Layer A/Layer B/Layer A were co-extruded into a film from a two-type three-layer T-die, and solidified on a casting drum maintained at a surface temperature of 160°C to obtain a multilayer film.
The draft ratio [Tt/Ft], which is the ratio of the gap thickness (Tt) of the lip portion of the T-die through which the melts of the first resin composition and the second resin composition are extruded to the thickness (Ft) of the multilayer film (laminate) formed by co-extrusion from the lip portion, is as shown in Table 1.

[Examples 2 to 9, 11 to 14, Comparative Example 4]
A multilayer film was obtained in the same manner as in Example 1, except that the resin compositions, layer configurations, and film molding conditions of Layer A and Layer B were changed as shown in Table 1.

[Example 10]
A multilayer film was obtained in the same manner as in Example 1, except that the resin composition, layer structure, and film molding conditions were changed as shown in Table 1. The P3MB and polypropylene used to form Layer B were all recycled raw materials. The P3MB and polypropylene contained in the recycled raw materials were obtained by recovering the film edge portions generated during the film production in Example 5, pulverizing them in a grinder, solidifying them in a granulator, and molding them into pellets.

[Comparative Example 1]
(1) Preparation of Resin Composition 100 parts by mass of P3MB (obtained in Production Example 1) was charged into a raw material inlet and melted at a cylinder temperature of 295°C using a vented twin-screw kneading extruder "KZW15-45" (manufactured by Technovel Corporation). Water was then removed from the shearing section of the extruder by vacuuming using a vacuum pump, yielding a pellet-shaped resin composition (M1).

(2) Production of a monolayer film The obtained pellet-like resin composition (M1) was molded under the following film-forming conditions to obtain a film. Specifically, the pellet-like resin composition (M1) was introduced into a raw material inlet, and molten at a cylinder temperature of 295°C using a vented twin-screw kneading extruder "KZW15-45" (manufactured by Technovel Co., Ltd.). After removing moisture by evacuating the shear section of the extruder using a vacuum pump, the extruded material was melt-extruded into a film from a T-die (gap thickness (Tt) of the lip of the T-die: 300 μm) and solidified on a casting drum maintained at a surface temperature of 160°C to obtain a monolayer film.

[Comparative Examples 2 to 3]
A single-layer film was obtained in the same manner as in Comparative Example 1, except that the resin composition and film molding conditions in Comparative Example 1 were changed as shown in Table 1.

[Comparative Example 5]
A film was obtained in the same manner as in Comparative Example 2, except that 100 parts by mass of polypropylene (trade name "Prime Polypro (registered trademark) PP E701G" manufactured by Prime Polymer Co., Ltd.) was replaced with 100 parts by mass of polymethylpentene (trade name "TPX (registered trademark) DX845" manufactured by Mitsui Chemicals, Inc.) and the film molding conditions were changed as shown in Table 1.

The physical properties of the films obtained in the examples and comparative examples were measured or evaluated using the following methods.

[Film thickness]
The film was cut from the center in the TD direction to a size of 100 mm in the TD direction × 100 mm in the MD direction to prepare a film sample. The thickness was measured at 11 points at 10 mm intervals from both ends of the film in the TD direction using a dial gauge thickness gauge (JIS B 7503:2017 compliant, "PEACOCK (registered trademark) UPRIIGHT DIAL GAUGE (graduation 0.001 mm, measurement range 2 mm, model No. 25, 5 mmφ flat probe)" manufactured by Ozaki Manufacturing Co., Ltd.), and the average value was used as the film thickness.
The MD direction ("MD" is an abbreviation for Machine Direction) corresponds to the longitudinal direction of the raw film during film production. The TD direction ("TD" is an abbreviation for Transverse Direction) refers to the direction perpendicular to the MD direction. The same applies hereinafter.

[Heat resistance]
A test piece measuring 4 mm in the TD direction and 25 mm in the MD direction was cut out from the center of the film obtained in each example. The dimensional change of the test piece was measured in accordance with JIS K 7197:1991 using a thermomechanical analyzer TMA ("Q400" manufactured by TA Instruments) at a temperature range of 25 to 300°C under the conditions of a chuck distance L of 8 mm, a load of 0.01 N, and a heating rate of 10°C/min. The absolute value of the linear expansion coefficient at 160 to 260°C or 160 to 240°C was calculated according to the following formula.
In the following formula, L (260°C) means the chuck distance (mm) of the test piece at 260°C, L (160°C) means the chuck distance (mm) of the test piece at 160°C, and L (240°C) means the chuck distance (mm) of the test piece at 240°C.
The smaller the absolute value of the linear expansion coefficient, the more excellent the heat resistance. Measurement was carried out only in the MD direction of the film, and the average value of the results of three measurements was taken as the absolute value of the linear expansion coefficient.
Absolute value of linear expansion coefficient from 160 to 260°C (ppm/°C) = 10 ⁶ × |L(260°C) - L(160°C)|/{8 × (260 - 160)}
Absolute value of linear expansion coefficient from 160 to 240°C (ppm/°C) = 10 ⁶ × |L(240°C) - L(160°C)|/{8 × (240 - 160)}
〔Judgment criteria〕
"S": The absolute value of the linear expansion coefficient between 160 and 260°C is 700 ppm/°C or less.
"A": The absolute value of the linear expansion coefficient between 160 and 260°C is more than 700 ppm/°C and 1,300 ppm/°C or less.
"B": The absolute value of the linear expansion coefficient between 160 and 260°C is more than 1,300 ppm/°C and 2,000 ppm/°C or less.
"C": The absolute value of the linear expansion coefficient between 160 and 240°C is 2,000 ppm/°C or less. (The absolute value of the linear expansion coefficient between 160 and 260°C could not be calculated because the film melted.)
"D": The absolute value of the linear expansion coefficient between 160 and 240°C is greater than 2,000 ppm/°C and less than 3,000 ppm/°C. (The absolute value of the linear expansion coefficient between 160 and 260°C could not be calculated because the film melted.)
"E": The absolute value of the linear expansion coefficient from 160 to 240°C and the absolute value of the linear expansion coefficient from 160 to 260°C could not be calculated because the film melted.

[Moldability]
A test piece measuring 75 mm in TD x 75 mm in MD was cut out from the center of the TD of each film obtained in each example, and a stretching test was carried out under the following conditions using a stretching machine (manufactured by Ever Sokki Co., Ltd., product name "Biaxial Stretching Birefringence Retardation Measurement Device"), and the results were used as an index of formability.
[Measurement conditions]
Preheating temperature: 150°C
Preheating time: 30 seconds; Stretching speed: 2.6 mm/min; Stretching temperature: 150°C
Stretching direction: uniaxial stretching in the MD direction Stretching ratio: 2 to 7 times [Evaluation: Standard]
"S": No tearing was observed at a stretching ratio of 6 times.
"A": Breaking was observed at a stretching ratio of 6 times, but no breakage was observed at a stretching ratio of 5 times.
"B": Breaking was observed at a stretching ratio of 5 times, but no breakage was observed at a stretching ratio of 3.5 times.
"C": Breaking was observed at a stretching ratio of 3.5 times, but no breakage was observed at a stretching ratio of 2 times.
"D": Breaking was observed at a stretching ratio of 2 times.

[Interlayer adhesion]
A test piece measuring 25 mm wide x 50 mm long was cut out from the film obtained in each example, and a peel test between layers A and B was carried out in accordance with JIS K 6854-1:1999 under the following conditions.
Peel tester: Peel tester (Shimadzu Corporation "AGS-X")
Peeling angle: 180°
Peeling speed: 100 mm/min Test temperature: 23°C
〔Judgment criteria〕
"S": Layer A and layer B were firmly adhered to each other, the peeling mode was cohesive failure, and the interlayer adhesion was good.
"D": The A layer and the B layer easily peeled off at the interface, and there was no interlayer adhesion.

[Flatness (degree of curl)]
The film was cut into a size of 100 mm x 100 mm to prepare a film sample, which was then left for 24 hours under atmospheric conditions of 25°C and 65% RH without any load being applied to the film sample, thereby conditioning the humidity of the film sample. After conditioning, the film sample was placed on a desk with good flatness without being secured with tape on all four sides (the casting drum surface of the film sample was the surface in contact with the desk), and the "floating" of the film from the desk was measured to evaluate the flatness.
The "floating" refers to the height (distance) of the most raised part of the film placed on the desk from the contact surface between the desk and the film, with the contact surface being set at 0 mm, and this "floating" was used as the value of "degree of curl" (unit: mm), which is an index for evaluating flatness. A smaller value of the degree of curl indicates better flatness.

[Transmission YI (D65)]
The yellowness index (YI value) of the film was measured using a spectrophotometer "SD7000" manufactured by Nippon Denshoku Industries Co., Ltd. under the condition of a D65 light source (viewing angle 10 degrees). After background measurement was performed without a sample, the film was set in a sample holder and transmittance measurement was performed for light of 380 nm to 780 nm to determine the tristimulus values (X, Y, Z). The YI value was calculated based on the following formula. Three measurements were performed, and the average of the results of each of the three measurements was taken as the yellowness index (YI value) of the film. This value is shown in Table 1 below as transmission YI (D65). The smaller the yellowness index (YI value) of the film, the better.
YI=100×(1.2769X-1.0592Z)/Y

In Table 1, in the "Resin composition" column, "P3MB" means the P3MB obtained in Production Example 1, and "PP" means polypropylene (product name "Prime Polypro (registered trademark) PP E701G", manufactured by Prime Polymer Co., Ltd.).
In Table 1, the values in parentheses in the "Resin Composition" column indicate the content (% by mass) of each component in 100% by mass of the total resin components in the resin composition. For example, "P3MB(50)+PP(50)" for Layer A means that, in 100% by mass of the total resin components in the first resin composition, the content of P3MB is 50% by mass and the content of polypropylene is 50% by mass.
In Table 1, "A layer/B layer/A layer" in the "Layer structure" column means a three-layer structure in which an A layer, a B layer, and an A layer are directly laminated in that order, and "(2/1/2)" means that the thickness ratio of the three layers (A layer:B layer:A layer) is 2:1:2.
In Table 1, "antioxidants, etc." refers to antioxidants, alkyl radical scavengers, and antacids. Therefore, the notation "present" for "antioxidants, etc." indicates that each antioxidant, alkyl radical scavenger, and antacid is contained in the same amount, and the notation "absent" for "antioxidants, etc." indicates that none of the antioxidants, alkyl radical scavengers, and antacids is contained.
In Table 1, "extrusion temperature" and "nitrogen purging" refer to "extrusion temperature" and "presence or absence of nitrogen purging" in "(1) Preparation of first resin composition,""(2) Preparation of second resin composition," and "(3) Production of film" in Examples 1 to 14 and Comparative Example 4, and refer to "extrusion temperature" and "presence or absence of nitrogen purging" in "(1) Preparation of resin composition" and "(2) Production of film" in Comparative Examples 1 to 3 and 5.
In Table 1, "draft ratio" refers to the draft ratio [Tt/Ft], which is the ratio between the gap thickness (Tt) of the lip portion of the T-die through which the melts of the first resin composition and the second resin composition are extruded and the thickness (Ft) of the laminate formed by co-extrusion from the lip portion, in Examples 1 to 14 and Comparative Example 4; and in Comparative Examples 1 to 3 and 5, it refers to the draft ratio [Tt/Ft], which is the ratio between the gap thickness (Tt) of the lip portion of the T-die through which the melt of the resin composition used to form the monolayer film is extruded and the thickness (Ft) of the monolayer film formed by extrusion from the lip portion.
In Table 1, the notation "(*1)" indicates that the molten material after extrusion was fused to the casting drum, making film formation impossible, and therefore evaluation was not possible.
In Table 1, the notation "(*2)" indicates that the evaluation was not possible due to delamination between the A layer and the B layer.

The results in Table 1 confirm that the multilayer films of Examples 1 to 14 are able to achieve both good heat resistance and formability compared to the films of the comparative examples.

On the other hand, the film of Comparative Example 1 was poor in formability because it was a single layer of P3MB.
Furthermore, the film of Comparative Example 2 was poor in heat resistance because it was a single layer of PP.
Furthermore, since the film of Comparative Example 3 was a single layer of PP, it had poor heat resistance, and when the surface temperature of the casting drum during film formation was set to 160°C, the molten material extruded from the T-die fused to the surface of the casting drum, making it impossible to form a film.
In addition, the film of Comparative Example 4 had poor interlayer peelability between layers A and B because layer B did not contain a polypropylene-based resin.
Furthermore, the film of Comparative Example 5 was poor in heat resistance and moldability because it was a single layer of TPX.

Claims (18)

A laminate containing a 3-methyl-1-butene polymer and a polypropylene resin,
the laminate includes at least two layers: a layer A formed from a first resin composition and a layer B formed from a second resin composition;
the content of the 3-methyl-1-butene polymer in the first resin composition is 10 to 100% by mass, based on 100% by mass of the total amount of resin components in the first resin composition;
the content of the polypropylene resin in the first resin composition is 0 to 90% by mass relative to 100% by mass of the total amount of resin components in the first resin composition;
the content of the 3-methyl-1-butene polymer in the second resin composition is 0 to 90% by mass relative to 100% by mass of the total amount of resin components in the second resin composition;
the content of the polypropylene resin in the second resin composition is 10 to 100% by mass, based on 100% by mass of the total amount of resin components in the second resin composition;
a laminate in which the content of the 3-methyl-1-butene polymer in the first resin composition based on mass, relative to 100% by mass of all resin components, is greater than the content of the 3-methyl-1-butene polymer in the second resin composition based on mass, relative to 100% by mass of all resin components. the content of the 3-methyl-1-butene polymer in the second resin composition is 0 to 40% by mass, relative to 100% by mass of the total amount of resin components in the second resin composition;
The laminate according to claim 1, wherein the content of the polypropylene-based resin in the second resin composition is 60 to 100 mass% in 100 mass% of the total amount of resin components in the second resin composition. The laminate described in claim 1 or 2, wherein at least one layer A and at least one layer B are directly laminated together. The laminate described in claim 3, wherein the A layer and the B layer have interlayer adhesion. The laminate described in claim 1 or 2, containing 1 to 100% by mass of recycled raw materials. The laminate according to claim 1 or 2, wherein the ratio of the thickness of the A layer to the thickness of the B layer [A layer/B layer] is 0.1 to 10. The laminate described in claim 1 or 2, having a yellowness index (YI) of 3.50 or less. The laminate according to claim 1 or 2, wherein the 3-methyl-1-butene polymer is at least one selected from the group consisting of 3-methyl-1-butene homopolymers and copolymers of 3-methyl-1-butene with at least one selected from the group consisting of ethylene and α-olefins having 3 to 20 carbon atoms other than 3-methyl-1-butene. The laminate according to claim 1 or 2, wherein the first resin composition further contains an antioxidant. The laminate according to claim 9, wherein the antioxidant is at least one selected from the group consisting of phenolic antioxidants and phosphorus-based antioxidants. The laminate according to claim 1 or 2, wherein the absolute value of the linear expansion coefficient at 160 to 260°C is 2,000 ppm/°C or less. The laminate according to claim 1 or 2, which is a film. A method for producing the laminate according to claim 1 or 2,
A method for producing a laminate, comprising: a step (I) of melt-extruding the first resin composition. The method for producing a laminate described in claim 13, wherein the first resin composition is melted in an inert atmosphere or in a low-oxygen state during step (I). The method for producing a laminate described in claim 13, wherein the first resin composition is melted at 280 to 323°C during step (I). The method for producing a laminate according to claim 13, further comprising step (II) of solidifying the molten extrudate of the first resin composition obtained in step (I) using a casting drum, wherein the temperature of the casting drum is 40 to 250°C. The method for producing a laminate according to claim 13, further comprising co-extruding the melt of the second resin composition and the melt of the first resin composition through a T-die during step (I). The method for producing a laminate according to claim 17, wherein a draft ratio [Tt/Ft], which is a ratio of a gap thickness (Tt) of a lip portion of the T-die to a thickness (Ft) of the laminate formed by coextrusion from the lip portion, is 1 to 30.