Laminated film, unstretched film, polypropylene-based polymer composition, and propylene-based polymer

Abstract

Disclosed are: a polypropylene-based polymer composition which contains 85-95 mass% of a resin A and 5-15 mass% of a resin B (provided that the total amount of the resin A and the resin B is 100 mass%); a laminated film which includes an unstretched film that is formed from the polymer composition and a layer that is formed by vapor-depositing an inorganic oxide; and a propylene-based polymer which contains the resin B. Resin A: A resin which has a melting point of 120-170 °C and a limiting viscosity (η) of more than 1.5 dl / g but not more than 5.0 dl / g. Resin B: A resin which contains 10-40 mass% of a propylene-based polymer (b1) that has a limiting viscosity (η) in the range of 10-12 dl / g and 60-90 mass% of a propylene-based polymer (b2) that has a limiting viscosity (η) in the range of more than 1.5 dl / g but not more than 2.5 dl / g (provided that the total amount of the polymer (b1) and the polymer (b2) is 100 mass%).

Description

Laminated film, unstretched film, polypropylene-based polymer composition, and propylene-based polymer

[0001] The present invention relates to an unstretched film, a polypropylene-based polymer composition, and a propylene-based polymer.

[0002] Propylene-based polymers are widely used as materials for various molded articles. For example, films made of propylene-based polymers are widely used as packaging films for food and miscellaneous goods, taking advantage of their excellent mechanical properties such as rigidity and optical properties such as gloss. In addition, unstretched polypropylene films are known to have a good balance of rigidity and heat resistance.

[0003] To preserve food for long periods, packaging materials with excellent gas barrier properties are used, blocking oxygen and water vapor from the outside air, which promote spoilage and deterioration. Conventional gas barrier materials include aluminum foil, aluminum vapor-deposited film, polyvinylidene chloride-coated film, and ethylene vinyl alcohol film.

[0004] On the other hand, transparent gas barrier films are known in which oxides such as silicon oxide and aluminum oxide are vapor-deposited on unstretched polypropylene films. Patent Document 1, for example, describes a transparent gas barrier unstretched polypropylene film that is transparent, has high gas barrier properties, and is excellent in secondary processability such as slitting and lamination, and is suitable for various packaging applications. The film is made by vapor-depositing a metal oxide on a film made of a mixed resin of 85 to 99% by weight of polypropylene random copolymer and 15 to 1% by weight of high-density polyethylene, to which 0.05 to 0.5 parts by weight of a lubricant has been added. The metal oxide vapor-deposited film has a Young's modulus of 0.7 GPa or more in at least one direction, a light transmittance of 60 to 90%, and a water vapor transmittance of 2.5 g / m. ２ Furthermore, Patent Document 2 discloses a metal oxide vapor-deposited unstretched polypropylene film having a density of 0.9 g / cm or less, which is transparent, has high gas barrier properties, and is excellent in secondary processability such as slitting and lamination, and is suitable for various packaging applications. ３The film is obtained by depositing a metal oxide on an unstretched film having a heat of crystalline fusion of 75 J / g or more, and the light transmittance of the metal oxide deposited film is 60 to 90% and the water vapor transmittance is 2.5 g / m ２ A metal oxide vapor-deposited unstretched film is disclosed, characterized in that the thickness is d or less.

[0005] JP-A-9-156021 JP-A-9-143294

[0006] In recent years, with the expansion of environmental regulations, the use of materials that generate incineration residues, such as aluminum foil, has been restricted. Furthermore, aluminum foil and aluminum-deposited films have the problem that the contents are not visible and cannot be heated in a microwave oven. Transparent gas barrier films have the advantages of excellent gas barrier properties, low environmental impact, allowing the contents to be seen, and being microwave-safe. However, the metal oxide-deposited unstretched polypropylene films described in Patent Documents 1 and 2 above have room for further improvement in terms of appearance (e.g., wrinkles on the film surface). Furthermore, the films described in Patent Documents 1 and 2 have room for further improvement in terms of gas barrier properties, particularly water vapor barrier properties.

[0007] An object of one embodiment of the present invention is to provide a laminate film that suppresses wrinkle formation and has excellent gas barrier properties. Another object of one embodiment of the present invention is to provide an unstretched polypropylene film that has excellent gas barrier properties. Another object of one embodiment of the present invention is to provide a polypropylene-based polymer composition and a propylene-based polymer that can provide a film that has excellent gas barrier properties.

[0008] Means for solving the above problems include the following aspects: <1> A laminated film comprising: an unstretched film formed from a polypropylene-based polymer composition containing 85 to 95% by mass of the following resin A and 5 to 15% by mass of the following resin B (where the total amount of the resin A and the resin B is 100% by mass), and a layer formed by vapor deposition of an inorganic oxide; Resin A: a propylene-based polymer having a melting point of 120 to 170°C and an intrinsic viscosity [η] in the range of more than 1.5 dl / g but not more than 5.0 dl / g; Resin B: A propylene polymer containing 10 to 40 mass% of a propylene polymer (b1) having an intrinsic viscosity [η] in the range of 10 to 12 dl / g, and 60 to 90 mass% of a propylene polymer (b2) having an intrinsic viscosity [η] in the range of more than 1.5 dl / g and not more than 2.5 dl / g (where the total amount of the propylene polymer (b1) and the propylene polymer (b2) is defined as 100 mass%). <2> The laminate film according to <1>, wherein the inorganic oxide contains aluminum oxide or silicon oxide. <3> The laminate film according to <1> or <2>, wherein the layer formed by vapor deposition of the inorganic oxide has a thickness of 5 to 100 nm. <4> The laminate film according to <1> or <2>, wherein the thickness of the layer formed by vapor deposition of the inorganic oxide is 5 to 100 nm. <5> The laminate film according to <1> or <2>, wherein the thickness of the layer is 5 to 100 nm. <6> The laminate film according to <1> or <2>, wherein the thickness of the layer is 5 to 100 nm. <7> The laminate film according to <1> or <2>, wherein the thickness of the layer is 5 to 100 nm. <8> The laminate film according to <1> or <2>, wherein the thickness of the layer is 5 to 100 nm. <9> The laminate film according to <1> or <2>, wherein the thickness of the layer is 5 to 100 nm. <10> The laminate film according to <1> or <2>, wherein the thickness of the layer is 5 to 100 nm. <11> The laminate film according to <1> or <2>, wherein the thickness of the layer is 5 to 100 nm. <12> The laminate film according to <1> or <2>, wherein the thickness of the layer is 5 to 100 nm. <13> The 3 / m 2<5> The laminate film according to any one of <1> to <4>, having a tensile modulus of elasticity in the MD direction at 80°C of 800 MPa or more. <6> The laminate film according to any one of <1> to <5>, having a tensile modulus of elasticity in the MD direction at 80°C of 800 MPa or more. <7> The laminate film according to any one of <1> to <6>, further comprising a biaxially oriented polypropylene film. <8> A polypropylene polymer composition comprising: 85 to 95% by mass of the following resin A; and 5 to 15% by mass of the following resin B (wherein the total amount of resin A and resin B is 100% by mass); resin A: a propylene polymer having a melting point of 120 to 170°C and an intrinsic viscosity [η] of more than 1.5 dl / g and not more than 5.0 dl / g; resin B: a propylene polymer comprising: 10 to 40% by mass of a propylene polymer (b1) having an intrinsic viscosity [η] of 10 to 12 dl / g; and 60 to 90% by mass of a propylene polymer (b2) having an intrinsic viscosity [η] of more than 1.5 dl / g and not more than 2.5 dl / g (wherein the total amount of the propylene polymer (b1) and the propylene polymer (b2) is 100% by mass). <9> An unstretched film formed from the polypropylene polymer composition according to <8>. <10> A propylene polymer comprising: 10 to 40 mass% of a propylene polymer (b1) having an intrinsic viscosity [η] in the range of 10 to 12 dl / g; and 60 to 90 mass% of a propylene polymer (b2) having an intrinsic viscosity [η] in the range of more than 1.5 dl / g and not more than 2.5 dl / g (wherein the total amount of the propylene polymer (b1) and the propylene polymer (b2) is 100 mass%).

[0009] According to one embodiment of the present invention, there is provided a laminate film that is excellent in wrinkle suppression and gas barrier properties. According to another embodiment of the present invention, there is provided an unstretched polypropylene film that is excellent in gas barrier properties. According to another embodiment of the present invention, there are provided a polypropylene-based polymer composition and a propylene-based polymer that can be used to obtain a film that is excellent in gas barrier properties.

[0010] Specific embodiments of the present invention will be described in detail below. The following description of the constituent elements may be based on a representative embodiment of the present invention, but the present invention is not limited to the following embodiment and can be implemented with appropriate modifications within the scope of the present invention. In this specification, a numerical range expressed using "to" means a range that includes the numerical values ​​written before and after "to" as the lower and upper limits. In this specification, when the amount of each component in a composition is referred to, if multiple substances corresponding to each component are present in the composition, the total amount of the multiple substances present in the composition is referred to unless otherwise specified. In this specification, the units written before or after "to" indicating a numerical range indicate the same unit unless otherwise specified. In this specification, a combination of two or more preferred embodiments is a more preferred embodiment. In this specification, the MD direction refers to the machine direction and refers to the extrusion direction during film molding and processing, and the TD direction refers to the transverse direction and refers to the direction perpendicular to the MD direction (i.e., the vertical direction). The present invention will now be described in further detail.

[0011] <Laminate Film> The laminate film of the present invention comprises a non-stretched film formed from a polypropylene-based polymer composition containing 85 to 95% by mass of the following resin A and 5 to 15% by mass of the following resin B (where the total amount of resin A and resin B is 100% by mass), and a layer formed by vapor deposition of an inorganic oxide. The laminate film having the above-described configuration exhibits excellent wrinkle suppression and gas barrier properties. While the reason for this is unclear, the following mechanism is presumed. Low-molecular-weight components in the polymer composition forming the resin film are presumed to flow due to the stress and heat applied during the vapor deposition process of the inorganic oxide onto the resin film. If the resin on the surface of the resin film flows during the vapor deposition of the inorganic oxide onto the resin film, there is a concern that fine voids will be generated between the barrier film (i.e., the layer formed by vapor deposition of the inorganic oxide) and the resin film, or that adhesion strength will decrease. Therefore, it is presumed that a lower content of low-molecular-weight components in the polymer composition is more effective in improving gas barrier properties. The laminate film of the present invention comprises a non-stretched film formed from a polypropylene-based polymer composition containing specific amounts of a specific resin A and a specific resin B. It is believed that by including the specific resin B in the polypropylene-based polymer composition, the amount of low-molecular-weight components in the polymer composition is reduced, and the laminate film has excellent gas barrier properties. The components contained in each layer constituting the laminate film will be described in detail below.

[0012] <Propylene-Based Polymer Composition> The propylene-based polymer composition contains 85 to 95 mass % of the following resin A and 5 to 15 mass % of the following resin B (where the total amount of resin A and resin B is 100 mass %). Because the propylene-based polymer composition contains specific amounts of resin A and resin B, the resulting film has excellent gas barrier properties and, when formed into a laminate film, is also excellent in suppressing the occurrence of wrinkles.

[0013] <<Resin A>> Resin A is a propylene polymer having a melting point of 120 to 170° C. and an intrinsic viscosity [η] in the range of more than 1.5 dl / g and not more than 5.0 dl / g.

[0014] [Melting Point (Tm)] The melting point (Tm) of Resin A is 120 to 170° C., and from the viewpoint of excellent moldability and heat resistance, it is preferably 125 to 170° C., more preferably 130 to 170° C. The melting point can be measured using a differential scanning calorimeter (DSC), and specifically, it is determined by the measurement method described in the examples.

[0015] [Intrinsic Viscosity [η]] The intrinsic viscosity [η] of Resin A is greater than 1.5 dl / g and not greater than 5.0 dl / g, preferably greater than 1.5 dl / g and not greater than 4.5 dl / g, and more preferably greater than 1.5 dl / g and not greater than 4.0 dl / g. When the intrinsic viscosity [η] is within the above range, productivity during film molding is good, and the resulting laminated film has excellent impact resistance. The intrinsic viscosity [η] is measured at 135°C in a tetralin solvent, and is determined by the measurement method described in the Examples.

[0016] [Melt flow rate (MFR)] The melt flow rate (MFR) of Resin A, measured at 230°C under a load of 2.16 kg, is preferably in the range of 5 to 40 g / 10 min, more preferably 6 to 35 g / 10 min. Use of Resin A having an MFR in the above range improves productivity during film molding and also improves the impact resistance of the resulting film.

[0017] [Molecular Weight Distribution (Mw / Mn)] The molecular weight distribution (Mw / Mn) of Resin A measured by gel permeation chromatography (GPC) is preferably 3.0 or more, more preferably 4.0 to 8.0, even more preferably 4.0 to 6.0, still more preferably 4.1 to 6.0, and particularly preferably 4.5 to 6.0. When Resin A has an Mw / Mn within the above range, the laminate film has excellent rigidity and transparency. The molecular weight distribution (Mw / Mn) is determined by the measurement method described in the Examples.

[0018] [Composition] The structure of resin (A) is not particularly limited, as long as it is a propylene-based polymer having a melting point of 120 to 170°C and an intrinsic viscosity [η] in the range of more than 1.5 dl / g and not more than 5.0 dl / g. Resin (A) may be, for example, a propylene homopolymer or a copolymer of propylene and an α-olefin (excluding propylene). Examples of the copolymer include a propylene-α-olefin random copolymer, a block-type propylene copolymer (a mixture of a propylene homopolymer or a propylene-α-olefin random copolymer with an amorphous or low-crystalline propylene-α-olefin random copolymer), and a random block polypropylene.

[0019] Examples of the α-olefin include α-olefins having 2 to 12 carbon atoms, such as ethylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-decene, 4-methyl-1-pentene, and 3-methyl-1-pentene. Of these α-olefins, ethylene, 1-butene, 1-hexene, 1-octene, and 4-methyl-1-pentene are preferred. One or more types of α-olefins can be used.

[0020] In a copolymer of propylene and an α-olefin, the content of structural units derived from propylene is usually 90 to 99.9% by mass, preferably 92 to 99.5% by mass, and more preferably 94 to 99% by mass, and the content of structural units derived from an α-olefin (excluding propylene) is usually 0.1 to 10% by mass, preferably 0.5 to 8% by mass, and more preferably 1 to 6% by mass. １３ It can be determined by measuring with C-NMR.

[0021] As the resin (A), a propylene homopolymer is preferred from the viewpoint of rigidity and impact strength.

[0022] The method for producing resin (A) is not particularly limited, and examples thereof include a production method in which propylene is homopolymerized or propylene is copolymerized with another α-olefin using a catalyst. Alternatively, commercially available polypropylene resins may be used as resin (A).

[0023] Examples of the catalyst used in producing Resin A include catalysts formed from a solid catalyst component containing magnesium, titanium, and a halogen as essential components, an organometallic compound catalyst component such as an organoaluminum compound, and an electron-donor compound catalyst component such as an organosilicon compound (typical examples include the catalysts described in paragraphs

[0050] to

[0075] of WO 2021 / 025142); and metallocene catalysts using a metallocene compound as one of the catalyst components.

[0024] Resin A may contain at least one type of biomass-derived monomer. The same type of monomer constituting Resin A may be composed solely of biomass-derived monomers, or may be composed solely of fossil fuel-derived monomers, or may contain both biomass-derived monomers and fossil fuel-derived monomers. The biomass-derived monomer is a monomer derived from any renewable natural raw material, such as a plant-derived or animal-derived material, including fungi, yeast, algae, and bacteria, and its residues, and contains, as carbon, １４ C isotope 1×10 －１２ The biomass-derived monomer is contained in a proportion of about 100, and the biomass carbon concentration (pMC) measured in accordance with ASTM D6866 is about 100 (pMC). There are no particular limitations on the method for synthesizing the biomass-derived monomer (e.g., propylene, α-olefins having 2 to 8 carbon atoms (excluding propylene), etc.), and any conventionally known method can be used. It is preferable for Resin A to contain a biomass-derived monomer from the viewpoint of reducing the environmental load. Note that, as long as the polymer production conditions, such as the polymerization catalyst and polymerization temperature, are equivalent, even if the raw material olefin is Resin A containing a biomass-derived olefin (i.e., a propylene-based polymer), １４ C isotope 1×10 －１２Other than the proportion of propylene in the resin, the molecular structure is the same as that of resin A (i.e., propylene polymer) made from fossil fuel-derived monomers, and the performance is said to be the same.

[0025] Resin A may contain at least one chemically recycled monomer. The same type of monomer constituting Resin A may consist solely of chemically recycled monomers, or may contain chemically recycled monomers in combination with fossil fuel-derived monomers and / or biomass-derived monomers. The method for synthesizing chemically recycled monomers (e.g., propylene, α-olefins having 2 to 8 carbon atoms (excluding propylene), etc.) is not particularly limited, and any conventionally known method can be used. It is preferable for Resin A to contain chemically recycled monomers from the perspective of reducing environmental impact (mainly waste reduction). Chemically recycled monomers are monomers obtained by depolymerizing or pyrolyzing polymers such as waste plastics back into monomer units such as propylene, as well as monomers produced using such monomers as raw materials. Therefore, even if the raw material monomer is a propylene-based polymer containing chemically recycled monomers, as long as the polymer production conditions, such as the polymerization catalyst, polymerization process, and polymerization temperature, are equivalent, the molecular structure and performance of the polymer are considered to be equivalent to those of Resin A composed of fossil fuel-derived monomers (i.e., propylene-based polymers).

[0026] <Resin B> Resin B is a propylene polymer containing 10 to 40 mass% of a propylene polymer (b1) having an intrinsic viscosity [η] in the range of 10 to 12 dL / g and 60 to 90 mass% of a propylene polymer (b2) having an intrinsic viscosity [η] in the range of more than 1.5 dL / g but not more than 2.5 dL / g (where the total amount of the propylene polymer (b1) and the propylene polymer (b2) is defined as 100 mass%). Note that the above-mentioned intrinsic viscosity [η] and the following intrinsic viscosity [η] are both intrinsic viscosities [η] measured at 135°C in a tetralin solvent, and are specifically determined by the measurement method described in the Examples below.

[0027] <<Propylene Polymer (b1)>> The intrinsic viscosity [η] of the propylene polymer (b1) is in the range of 10 to 12 dL / g, and preferably in the range of 10.5 to 11.5 dL / g.

[0028] When the intrinsic viscosity [η] is 10 dL / g or more, the laminated film has excellent rigidity and heat resistance.When the intrinsic viscosity [η] is 12 dL / g or less, an unstretched film can be produced with excellent formability, and the occurrence of wrinkles on the film surface can be effectively suppressed.

[0029] The mass fraction of the propylene polymer (b1) in the resin (B) is in the range of 10 to 40% by mass, preferably 10 to 30% by mass, more preferably 10 to 25% by mass, and even more preferably 10 to 20% by mass. The total amount of the propylene polymer (b1) and the propylene polymer (b2) is defined as 100% by mass. When the mass fraction of the propylene polymer (b1) is 10% by mass or more, the propylene polymer composition has sufficient melt tension and can form an unstretched film having excellent rigidity and heat resistance. When the mass fraction of the propylene polymer (b1) is 40% by mass or less, the occurrence of wrinkles during molding into an unstretched film can be suppressed.

[0030] The propylene polymer (b1) is not particularly limited, and examples thereof include a propylene homopolymer and a copolymer of propylene and an α-olefin having 2 to 8 carbon atoms (excluding propylene). Examples of the α-olefin having 2 to 8 carbon atoms include ethylene, 1-butene, 1-hexene, 1-octene, and 4-methyl-1-pentene. Ethylene is preferred as the α-olefin having 2 to 8 carbon atoms. The α-olefin having 2 to 8 carbon atoms may be used alone or in combination of two or more.

[0031] In a copolymer of propylene and an α-olefin having 2 to 8 carbon atoms, the content of structural units derived from propylene is usually 90% by mass or more, preferably 95% by mass or more, and more preferably 98% by mass or more, and the content of structural units derived from an α-olefin having 2 to 8 carbon atoms (excluding propylene) is usually 10% by mass or less, preferably 5% by mass or less, and more preferably 2% by mass or less.１３ The propylene polymer (b1) may be used singly or in combination of two or more thereof.

[0032] <<Propylene Polymer (b2)>> The propylene polymer (b2) has an intrinsic viscosity [η] of more than 1.5 dL / g to 2.5 dL / g or less, preferably 1.8 to 2.5 dL / g, and more preferably 2.2 to 2.5 dL / g. When the intrinsic viscosity [η] exceeds 1.5 dL / g, sufficient melt tension can be imparted to the resin (B), and when the intrinsic viscosity [η] is 2.5 dL / g or less, excellent molding properties are obtained for forming an unstretched film.

[0033] The mass fraction of the propylene polymer (b2) in the resin (B) is in the range of 60 to 90 mass%, preferably 70 to 90 mass%, more preferably 75 to 90 mass%, and even more preferably 80 to 90 mass%, where the total amount of the propylene polymer (b1) and the propylene polymer (b2) is 100 mass%. When the mass fraction of the propylene polymer (b2) is 60 mass% or more, the occurrence of wrinkles during molding into an unstretched film can be suppressed. When the mass fraction of the propylene polymer (b2) is 90 mass% or less, sufficient melt tension can be imparted to the resin (B), and the resulting laminated film has excellent rigidity and heat resistance.

[0034] The propylene polymer (b2) is not particularly limited, and examples thereof include a propylene homopolymer and a copolymer of propylene and an α-olefin having 2 to 8 carbon atoms (excluding propylene). Examples of the α-olefin having 2 to 8 carbon atoms include ethylene, 1-butene, 1-hexene, 1-octene, and 4-methyl-1-pentene. Ethylene is preferred as the α-olefin having 2 to 8 carbon atoms. The α-olefin having 2 to 8 carbon atoms may be used alone or in combination of two or more.

[0035] In a copolymer of propylene and an α-olefin having 2 to 8 carbon atoms, the content of structural units derived from propylene is usually 90% by mass or more, preferably 93% by mass or more, and more preferably 94% by mass or more, and the content of structural units derived from an α-olefin having 2 to 8 carbon atoms (excluding propylene) is usually 10% by mass or less, preferably 7% by mass or less, and more preferably 6% by mass or less. １３ The propylene polymer (b2) may be used alone or in combination of two or more.

[0036] Resin B may contain additives such as antioxidants, neutralizing agents, flame retardants, and crystal nucleating agents, as needed. The additives may be used alone or in combination. The proportion of the additives in Resin B is not particularly limited and can be adjusted as appropriate.

[0037] <<Physical Properties of Resin B>> [Melt Flow Rate (MFR)] Resin B preferably has a melt flow rate (MFR) measured at 230°C under a load of 2.16 kg in the range of 0.01 to 5 g / 10 min, more preferably 0.05 to 4 g / 10 min, and even more preferably 0.1 to 3 g / 10 min. When the MFR of Resin B is in the above range, the propylene polymer composition is excellent in formability into an unstretched film.

[0038] [Area Proportion of High Molecular Weight Region with Molecular Weight of 1,500,000 or More] Resin B has an area proportion of high molecular weight regions with molecular weights of 1,500,000 or more (i.e., corresponding to the mass proportion of high molecular weight components with molecular weights of 1,500,000 or more) of the total area surrounded by a molecular weight distribution curve measured by gel permeation chromatography (GPC) of preferably 7% or more, more preferably 10% or more, and even more preferably 11% or more. The upper limit of this area proportion is, for example, 30% or less, preferably 25% or less.

[0039] The area ratio of the high molecular weight region being equal to or greater than a specific ratio means that resin B contains high molecular weight components having a molecular weight of 1.5 million or more. At least a portion of these high molecular weight components corresponds to high molecular weight components having an intrinsic viscosity [η] of 10 to 12 dL / g. Therefore, when the ratio of the high molecular weight components is within the above range, resin B has a superior melt tension.

[0040] [(MH / ML)] Resin B preferably has two peaks in the molecular weight distribution curve measured by GPC. Here, the ratio of the peak molecular weight (MH) on the high molecular weight side to the peak molecular weight (ML) on the low molecular weight side (hereinafter sometimes referred to as "MH / ML") is preferably 10 or more and 100 or less, more preferably 10 or more and 70 or less, even more preferably 13 or more and 50 or less, still more preferably 15 or more and 50 or less, and particularly preferably 15 or more and 49 or less. When MH / ML is 10 or more, the gas barrier property is further improved, and when MH / ML is 100 or less, the occurrence of wrinkles can be further suppressed.

[0041] [Peak Molecular Weight (ML)] From the viewpoints of excellent viscosity and moldability of the propylene polymer composition into an unstretched film, Resin B preferably has a peak molecular weight (ML) on the low-molecular-weight side of a molecular weight distribution curve measured by GPC of 20,000 or more and 300,000 or less, more preferably 50,000 or more and 250,000 or less, even more preferably 100,000 or more and 200,000 or less, and still more preferably 110,000 or more and 200,000 or less.

[0042] [Fisheyes (FE)] Resin B usually has a number of fisheyes (FE) (FE number) of 100 or less, preferably 70 or less, and more preferably 50 or less. If the FE number exceeds 100, the appearance of the unstretched film may be poor. By setting the FE number of Resin B within the above range, a film with good appearance can be obtained. The FE number is measured as follows. A film having a thickness of 50 μm is produced from Resin B using a 25 mmΦ T-die film-forming machine. For the obtained film, a fisheye (FE) counter is used to measure the number of FEs with a size of 100 μm or more, and the number of FEs per unit area (3000 cm) is calculated. ２The number of FEs can be calculated by converting the number of FEs per 1000 particles into the number of FEs per 1000 particles.

[0043] <<Method for producing resin B>> The method for producing resin B is not particularly limited, and various known production methods can be used. For example, the methods described in paragraphs

[0038] to

[0075] of WO 2021 / 025142 can be used.

[0044] Resin B may contain at least one type of biomass-derived monomer. The same type of monomer constituting Resin B may consist solely of biomass-derived monomers, or may consist solely of fossil fuel-derived monomers, or may contain both biomass-derived monomers and fossil fuel-derived monomers. The biomass-derived monomers and fossil fuel-derived monomers are synonymous with the biomass-derived monomers and fossil fuel-derived monomers in Resin A. Resin B may also contain at least one type of chemically recycled monomer. The same type of monomer constituting Resin B may consist solely of chemically recycled monomers, or may contain chemically recycled monomers and fossil fuel-derived monomers and / or biomass-derived monomers. The chemically recycled monomers are synonymous with the chemically recycled monomers in Resin A.

[0045] [Additives] The propylene polymer composition may contain additives such as weather resistance stabilizers, heat resistance stabilizers, antistatic agents, slip agents, antiblocking agents, antifogging agents, nucleating agents, decomposing agents, pigments, dyes, plasticizers, hydrochloric acid absorbers, antioxidants, crosslinking agents, crosslinking accelerators, reinforcing agents, fillers, softeners, processing aids, activators, moisture absorbents, adhesives, flame retardants, and mold release agents, within the scope of the object of the present invention. The additives may be used alone or in combination of two or more.

[0046] The propylene polymer composition may contain a nucleating agent to improve transparency, heat resistance, etc. Examples of nucleating agents include sorbitol compounds such as dibenzylidene sorbitol, organic phosphate ester compounds, rosinate compounds, and C4 to C12 (i.e., carbon number 4 to 12) aliphatic dicarboxylic acids and metal salts thereof. Among these, organic phosphate ester compounds are preferred as nucleating agents.

[0047] The nucleating agent can be used alone or in combination with other nucleating agents, and is preferably used in an amount of 0.05 to 0.5 parts by mass, more preferably 0.1 to 0.3 parts by mass, per 100 parts by mass of the total of Resin A and Resin B.

[0048] The propylene polymer composition may contain, as necessary, resins other than the resin A and the resin B (hereinafter also referred to as "other resins"). Examples of other resins include polyethylene. The content of the other resins is preferably 2 parts by mass or less, more preferably 1 part by mass or less, and even more preferably 0.5 parts by mass or less, relative to 100 parts by mass of the total of the resin A and the resin B.

[0049] The lower limit of the molecular weight distribution (Mw / Mn) of the propylene polymer composition measured by gel permeation chromatography (GPC) is preferably 5.0 or more, more preferably 5.5 or more, and even more preferably 6.0 or more. The upper limit of the molecular weight distribution (Mw / Mn) is not particularly limited, but is, for example, 25 or less, preferably 20 or less, more preferably 15 or less, and even more preferably 10 or less. Here, Mn is the number average molecular weight, and Mw is the weight average molecular weight. The molecular weight distribution (Mw / Mn) is determined by the measurement method described in the Examples below.

[0050] The use of a propylene polymer (b1) with a high molecular weight results in a wide molecular weight distribution of the propylene polymer composition. Therefore, it is presumed that the degree of orientation in the MD direction of molding increases during film formation of the propylene polymer composition, and the orientation results in high crystallinity of the propylene polymer. This is thought to be why a film with excellent rigidity, heat resistance, and gas barrier properties was obtained.

[0051] The melt flow rate (MFR) of the propylene polymer composition measured at 230°C under a load of 2.16 kg is usually 1 to 30 g / 10 min, preferably 2 to 28 g / 10 min, and more preferably 3 to 25 g / 10 min.

[0052] In the propylene polymer composition, the content of resin A is 85 to 95% by mass, preferably 86 to 93% by mass, and more preferably 88 to 92% by mass, and the content of resin B is 5 to 15% by mass, preferably 6 to 13% by mass, and more preferably 8 to 12% by mass. However, the total amount of resin A and resin B is 100% by mass. When the content of resin A is within the above range, the rigidity, heat resistance, and gas barrier properties are excellent, and the transparency of the obtained film and the suppression of wrinkle formation are excellent. Resin A and resin B may each be contained alone in the composition, or two or more types may be contained in the composition.

[0053] In the polypropylene polymer composition of the present invention containing Resin A and Resin B, the content ratio of (structural units derived from ethylene and structural units derived from an α-olefin having 4 to 20 carbon atoms) / (structural units derived from propylene, structural units derived from ethylene, and structural units derived from an α-olefin having 4 to 20 carbon atoms) is preferably 10% by mass or less, more preferably 8% by mass or less, even more preferably 4% by mass or less, particularly preferably less than 2% by mass, and most preferably 1.4% by mass or less.

[0054] <<Method for producing propylene polymer composition>> The propylene polymer composition can be produced by employing any known method, and examples thereof include a method in which Resin A, Resin B, and optional additives are mixed using a Henschel mixer, a V-type blender, a ribbon blender, a tumbler blender, or the like; and a method in which the mixed mixture is melt-kneaded using a single-screw extruder, a twin-screw extruder, a kneader, a Banbury mixer, a roll, or the like, and then granulated or pulverized.

[0055] From the viewpoints of the rigidity and heat resistance of the obtained film and the reduction of fisheyes, the method for producing the propylene polymer composition is preferably a method in which the propylene polymer composition is prepared by mixing the resin A with the resin B containing the propylene polymer (b1) and the propylene polymer (b2) obtained by batchwise multistage polymerization.

[0056] <Non-stretched film> The non-stretched film according to the present invention is formed from the propylene-based polymer composition. Since the non-stretched film contains the specific propylene-based polymer composition, it exhibits higher rigidity, heat resistance, and gas barrier properties than conventional non-stretched polypropylene films. The non-stretched film is suitable for use as a packaging material for, for example, food, beverages, industrial parts, miscellaneous goods, toys, daily necessities, office supplies, medical supplies, etc.

[0057] The thickness of the non-stretched film is usually less than 200 μm, preferably 10 to 150 μm, more preferably 15 to 100 μm. The non-stretched film according to the present invention has excellent rigidity, and therefore can be easily made thinner.

[0058] The unstretched film has a unit area (3000 cm ) measured using a fisheye (FE) counter. 2 The number of FEs converted into the number of FEs per unit area is preferably 100 or less, more preferably 70 or less, and even more preferably 50 or less. An unstretched film having an FE number of not more than the upper limit can be said to have a good appearance.

[0059] The method for forming the non-stretched film is not particularly limited, and examples thereof include extrusion molding methods such as a T-die method and an inflation method, compression molding, calendar molding, and casting. Non-stretched film formation can be performed, for example, as follows. The components constituting the propylene polymer composition may be directly charged into a hopper or the like of a film forming machine, or the components may be premixed using a ribbon blender, a Banbury mixer, a Henschel mixer, a super mixer, or the like, or may be melt-kneaded using a kneader such as a single-screw or twin-screw extruder or a roll to obtain a propylene polymer composition, which may then be formed into a film.

[0060] A specific example of the production of an unstretched film will be explained using the T-die method. The above components are charged into an extruder and melt-kneaded usually at a temperature of 180 to 280°C, preferably 200 to 270°C, and then extruded into a film form from the die lip of a T-die. The molten film is cooled and taken up by a take-up machine such as nip rolls to obtain a film.

[0061] Examples of methods for cooling the molten film include cooling using rolls and air, such as the air knife method or air chamber method; narrow pressure cooling, such as the polishing roll method, swing roll method, or belt casting method; and contact cooling with a refrigerant, such as water cooling.

[0062] The obtained unstretched film may be subjected to a film treatment method typically used in film molding, such as corona discharge treatment or liquid coating treatment.

[0063] <<Inorganic Oxide Layer>> The laminate film includes a layer formed by vapor-depositing an inorganic oxide (hereinafter, may be simply referred to as "inorganic oxide layer"). From the viewpoint of achieving better gas barrier properties, it is preferable that the non-stretched film and the inorganic oxide layer are in contact with each other in part or in whole. From the viewpoint of achieving better gas barrier properties and better suppression of wrinkle formation, it is preferable that the inorganic oxide layer is a layer formed by vapor-depositing an inorganic oxide onto a non-stretched film. Methods for vapor-depositing an inorganic oxide onto a non-stretched film include conventionally known methods, such as chemical vapor deposition (CVD) and physical vapor deposition (PVD).

[0064] Examples of inorganic oxides include inorganic oxides of aluminum, zinc, magnesium, silicon, etc. Among these, from the viewpoint of excellent gas barrier properties, the inorganic oxide preferably includes aluminum oxide or silicon oxide, and more preferably is aluminum oxide or silicon oxide.

[0065] The thickness of the inorganic oxide layer is preferably 5 to 100 nm, more preferably 10 to 40 nm, even more preferably 10 to 30 nm, and particularly preferably 10 to 20 nm. When the thickness of the inorganic oxide layer is within the above range, the gas barrier property and the suppression of wrinkle formation are more excellent. The thickness of the inorganic oxide layer can be measured by the method employed in the examples described below.

[0066] The laminate film may include two or more layers of the above-mentioned non-stretched film, or may further include layers other than the non-stretched film and the inorganic oxide layer (hereinafter also referred to as "other layers"). Having a multilayer laminate film allows the film to be endowed with a variety of additional functions. The other layer may be one layer, or two or more layers. Examples of locations where the other layer may be provided include: the side of the non-stretched film opposite the inorganic oxide layer; a location between the non-stretched film and the inorganic oxide layer where the non-stretched film and the inorganic oxide layer are not in contact with each other; and the side of the inorganic oxide layer opposite the non-stretched film.

[0067] Examples of the other layers include a biaxially oriented polypropylene film, a gas barrier layer against gases such as water vapor and oxygen, a sound absorbing layer, a light blocking layer, an adhesive layer, a pressure-sensitive adhesive layer, a colored layer, a conductive layer, a recycled resin-containing layer, a coating layer, etc. Specific examples of materials for forming the other layers include olefin polymer compositions other than resin A and resin B, gas barrier resin compositions, adhesive resin compositions, etc.

[0068] From the viewpoint of achieving better gas barrier properties, it is preferable that the laminate film further comprises a coating layer. The coating layer is preferably provided between the non-stretched film and the inorganic compound layer or on the inorganic compound layer (i.e., on the side of the laminate film opposite the non-stretched film). The coating layer may be formed on one side of the inorganic compound layer or on both sides. When coating layers are formed on both sides of the inorganic compound layer, the gas barrier properties are even better. The coating agent for forming the coating layer is not particularly limited, and examples thereof include known anchor coating agents and top coating agents. Examples of coating agents include two-component mixed urethane coating agents, such as those manufactured by Mitsui Chemicals, Inc., under the trade names "Takenate" and "Takelac."

[0069] The laminate film preferably further comprises a biaxially oriented polypropylene film. When a biaxially oriented polypropylene film is provided, it is preferably provided on the side opposite the non-oriented film, and more preferably on the side opposite the non-oriented film via an adhesive layer in contact with the inorganic oxide layer. The adhesive layer is not particularly limited, and examples thereof include layers formed from anchor coating agents such as urethane-based or isocyanate-based adhesives, or adhesive resins such as modified polyolefins, e.g., unsaturated carboxylic acid-grafted polyolefins. When the laminate film comprises a biaxially oriented polypropylene film, it is preferable from the viewpoint of mono-materialization and reduced environmental impact compared to laminate films comprising biaxially oriented films such as biaxially oriented polyethylene terephthalate film and biaxially oriented nylon film.

[0070] The method for forming the other layers is not particularly limited, and includes known molding methods such as coextrusion and extrusion coating.

[0071] The water vapor permeability of the laminated film is preferably 15 (g / m ２ ·day) or less, more preferably 10 (g / m ２ The water vapor transmission rate of the laminated film can be adjusted, for example, by changing the film thickness of the layer on which the inorganic oxide is vapor-deposited.

[0072] The oxygen gas permeability of the laminate film is preferably 2000 (cm ３ / m ２ ·day·atm) or less, and more preferably 1000 (cm ３ / m ２ ·day·atm) or less, and more preferably 100 (cm ３ / m ２ The oxygen gas permeability can be adjusted by changing the film thickness of the layer on which the inorganic oxide is vapor deposited.

[0073] The tensile modulus of the laminate film at 80°C is preferably 800 MPa or more, more preferably 850 MPa or more, and the upper limit of the tensile modulus is not particularly limited and may be, for example, 1300 MPa or less. In a preferred embodiment of the laminate film, the tensile modulus of the laminate film in the MD direction at 80°C is preferably 800 MPa or more, more preferably 850 MPa or more. There is no upper limit to the tensile modulus of the laminate film in the MD direction at 80°C, but it may be, for example, 1300 MPa or less. This tensile modulus value can be adjusted, for example, by changing the film take-up speed during film formation. The tensile modulus is measured by the method used in the examples described below.

[0074] [Uses] The laminate film is used, for example, as a packaging material for foods, beverages, industrial parts, miscellaneous goods, toys, daily necessities, office supplies, medical supplies, etc. The laminate film can be used as a packaging film in a wide range of packaging fields, for example, in the field of packaging various foods such as fresh foods such as fish and meat, dried foods such as snacks and noodles, and watery foods such as soups and pickles; the field of packaging medical products such as medical products in various forms such as tablets, powders, and liquids, and medical peripheral materials; and the field of packaging various electrical equipment such as cassette tapes and electrical components.

[0075] Hereinafter, one embodiment of the present invention will be described with reference to examples, but the present invention is not limited to these examples. The various properties of the polymer, polymer composition, unstretched film, and laminated film obtained in each example were measured and evaluated as follows.

[0076] [Intrinsic viscosity [η]] The intrinsic viscosity [η] (dl / g) was measured in a tetralin solvent at 135° C. The intrinsic viscosity [η] of the propylene polymer (corresponding to the propylene polymer (b2)) obtained in the second stage in the production of Resins B-1, B-2, and B-3 was ２ is a value calculated using the following formula: [η] ２ = ([η] ｔｏｔａｌ ×100-[η] １ ×W １ ) / W ２ [η] ｔｏｔａｌ : Intrinsic viscosity of the entire propylene polymer [η] １ W: Intrinsic viscosity of the propylene polymer obtained in the first stage １ W: mass fraction (%) of the propylene polymer obtained in the first stage ２ : Mass fraction (%) of the propylene polymer obtained in the second stage

[0077] [Melt Flow Rate (MFR)] The melt flow rate (MFR) (g / 10 min) was measured in accordance with JIS-K7210 at a measurement temperature of 230° C. and a load of 2.16 kgf (21.2 N).

[0078] [Proportion of high molecular weight region with a molecular weight of 1.5 million or more, ML, MH / ML, and molecular weight distribution (Mw / Mn)] The proportion of high molecular weight region with a molecular weight of 1.5 million or more is the area ratio of high molecular weight region with a molecular weight of 1.5 million or more to the total area surrounded by the molecular weight distribution curve (specifically, the molecular weight distribution curve and the horizontal axis) measured by gel permeation chromatography (GPC) using the following equipment and conditions. Here, the horizontal axis is the molecular weight (logarithmic value), and the vertical axis is dw / dLog(M) [w: cumulative mass fraction, M: molecular weight]. The peak molecular weight MH on the high molecular weight side and the peak molecular weight ML on the low molecular weight side of the molecular weight distribution curve were obtained, and the MH / ML was calculated. In addition, the average molecular weight (number average molecular weight Mn and weight average molecular weight Mw) was obtained from the molecular weight distribution curve, and the molecular weight distribution (Mw / Mn) was calculated.

[0079] - GPC measurement device - Gel permeation chromatograph HLC-8321 GPC / HT type (manufactured by Tosoh Corporation) Analysis device Data processing software Empower 3 (manufactured by Waters Corporation) Measurement conditions Column: TSKgel GMH6-HT x 2 + TSKgel GMH6-HTL x 2 (both 7.5 mm I.D. x 30 cm, manufactured by Tosoh Corporation) Column temperature: 140°C Mobile phase: o-dichlorobenzene (containing 0.025% BHT) Detector: differential refractometer Flow rate: 1.0 mL / min Sample concentration: 0.1% (w / v) Injection volume: 0.4 mL Sampling time interval: 1 s Column calibration: monodisperse polystyrene (manufactured by Tosoh Corporation) Molecular weight conversion: PP conversion / general calibration method (viscosity conversion coefficient K for PS (polystyrene) PS = 0.000138 dl / g, α PS = 0.700, viscosity conversion factor for PP (polypropylene) K PP = 0.000242 dl / g, α PP = 0.707

[0080] [Melting Point (Tm)] The crystalline melting point was determined in accordance with JIS-K7121 by measuring under the following measurement conditions using a differential scanning calorimeter (DSC, manufactured by PerkinElmer (Diamond DSC)). The apex of the endothermic peak in the fourth step when the measurement was performed under the following measurement conditions was defined as the crystalline melting point (Tm). When there are multiple endothermic peaks, the apex of the endothermic peak with the greatest peak height is defined as the crystalline melting point (Tm). (Measurement Conditions) Measurement environment: Nitrogen gas atmosphere Sample amount: 5 mg Sample shape: Press film (formed at 230°C, thickness 400 μm) Sample pan: Aluminum sample pan with a flat bottom First step: Heat from 30°C to 200°C at 320°C / min and hold for 10 min. Second step: Cool to 30°C at 20°C / min. Third step: Maintain at 30°C for 10 minutes. Fourth step: Increase the temperature to 200°C at a rate of 20°C / min.

[0081] [Fisheyes (FE)] The number of fisheyes was measured by counting the number of FEs in a 50 μm thick film made using Resin B (propylene polymer (B)) with a 25 mm diameter T-die film-making machine manufactured by Plastics Engineering Research Institute Co., Ltd., using a Fisheye Counter (registered trademark) manufactured by Hutec Co., Ltd. as a gel counter. FEs with a size of 100 μm or more were counted. The number of fisheyes measured was calculated based on the unit area of ​​the film (3000 cm 2 ) and is shown as the number of FEs per unit area. The film production conditions are as follows: T-die film-making machine: manufactured by Plastics Technology Research Institute Co., Ltd. Model: GT-25-A Screw diameter: 25 mm, L / D = 24 Screw rotation speed: 60 rpm Cylinder temperature settings: C1 = 230°C, C2 = 260°C Head temperature setting: 260°C T-die temperature settings: D1 to D3 = 260°C T-die width: 230 mm, lip opening = 1 mm Film winding speed: 4 m / s Roll temperature: 65°C The measurement conditions for the gel counter are as follows: Device configuration - Photodetector (4096 pixels) - Projector - Signal processing device - Pulse generator - Cable between devices

[0082] <Resin A> Resin A-1 was a propylene homopolymer (manufactured by Prime Polymer Co., Ltd., trade name: Prime Polypro F-704NP) having an MFR (230°C, 2.16 kg load): 7.0 g / 10 min, an intrinsic viscosity [η]: 1.8 dl / g, a melting point: 165°C, and an Mw / Mn ratio of 4.8.

[0083] Resin A-2 used was a propylene homopolymer (manufactured by Prime Polymer Co., Ltd., trade name: Prime Polypro F107BA) having an MFR (230°C, 2.16 kg load): 7.2 g / 10 min, an intrinsic viscosity [η]: 1.8 dl / g, a melting point: 165°C, and an Mw / Mn: 4.8.

[0084] Resin A-3 was prepared by the following manufacturing method. [Preparation of Solid Titanium Catalyst Component (a-3)] 95.2 g of anhydrous magnesium chloride, 442 mL of decane, and 390.6 g of 2-ethylhexyl alcohol were heated and reacted at 130°C for 2 hours to form a homogeneous solution, and then 21.3 g of phthalic anhydride was added to this solution, followed by stirring and mixing at 130°C for 1 hour to dissolve the phthalic anhydride. The homogeneous solution thus obtained was cooled to room temperature, and then 75 mL of this homogeneous solution was added dropwise over 1 hour to 200 mL of titanium tetrachloride maintained at -20°C. After completion of the addition, the temperature of this mixture was raised to 110°C over 4 hours. When the temperature reached 110°C, 5.22 g of diisobutyl phthalate (DIBP) was added, and the mixture was maintained with stirring at the same temperature for another 2 hours. After the 2-hour reaction, the solid was collected by hot filtration, resuspended in 275 mL of titanium tetrachloride, and heated again at 110°C for 2 hours. After the reaction was completed, the solid was collected again by hot filtration and thoroughly washed with decane and hexane at 110°C until no free titanium compounds were detected in the solution. The solid titanium catalyst component prepared as above was stored as a hexane slurry, and a portion of this was dried to examine the catalyst composition. The solid titanium catalyst component contained 2.3% by mass of titanium, 61% by mass of chlorine, 19% by mass of magnesium, and 12.5% ​​by mass of DIBP.

[0085] [Production of Prepolymerization Catalyst (a-3)] 100.0 g of solid titanium catalyst component (a-3), 22.4 mL of dicyclopentyldimethoxysilane, 65.6 mL of triethylaluminum, and 10 L of heptane were charged into a 20 L autoclave equipped with a stirrer, and 600 g of propylene was charged while maintaining the internal temperature at 15 to 20°C, and the reaction was carried out with stirring for 100 minutes. After completion of polymerization, the solid component was allowed to settle, and the supernatant was removed and washed with heptane twice. The obtained prepolymerization catalyst was resuspended in purified heptane and adjusted with heptane so that the solid catalyst component concentration was 1.0 g / L.

[0086] [Production of Resin A-3] To a 58 L tubular polymerization vessel, 43 kg / h of propylene, 163 NL / h of hydrogen, 0.55 g / h of prepolymerization catalyst (a-3), 1.9 mL / h of triethylaluminum, and 3.8 mL / h of dicyclopentyldimethoxysilane were continuously fed, and polymerization was carried out in a liquid-filled state with no gas phase present. The temperature of the tubular polymerization vessel was 70°C, and the pressure was 3.5 MPa / G. The obtained slurry was sent to a 70 L vessel polymerization vessel equipped with a stirrer, where further polymerization was carried out. To the polymerization vessel, 45 kg / h of propylene and hydrogen were fed so that the hydrogen concentration in the gas phase was 15.8 mol%. Polymerization was carried out at a polymerization temperature of 63°C and a pressure of 3.2 MPa / G. The obtained slurry was deactivated, and the propylene was evaporated to obtain a powdery propylene homopolymer (Resin A-3). Resin A-3 had an MFR of 30 g / 10 min and an Mw / Mn of 5.2.

[0087] [Production of Resin B-1] (1) Preparation of Solid Catalyst Component 30 kg of the above magnesium compound (unground), 150 L of purified heptane (n-heptane), 4.5 L of silicon tetrachloride, and 5.4 L of di-n-butyl phthalate were added to a reactor equipped with a stirrer (internal volume 500 L) that had been thoroughly purged with nitrogen gas. The system was maintained at 90°C, and 144 L of titanium tetrachloride was added with stirring. The reaction was carried out at 110°C for 2 hours, after which the solid component was separated and washed with purified heptane at 80°C. Further, 228 L of titanium tetrachloride was added, and the reaction was carried out at 110°C for 2 hours. The solid component was then thoroughly washed with purified heptane to obtain a solid catalyst component.

[0088] (2) Preparation of Prepolymerization Catalyst 10 mmol of triethylaluminum, 2 mmol of dicyclopentyldimethoxysilane, and 1 mmol of the solid catalyst component obtained in (1) above (calculated as titanium atom) were added to 200 mL of heptane. The internal temperature was maintained at 20°C, and propylene was continuously introduced with stirring. After 60 minutes, stirring was stopped, resulting in a prepolymerization catalyst in which 4.0 g of propylene had been polymerized per 1 g of solid catalyst.

[0089] (3) Main polymerization: 336 L of propylene was charged into a 600 L autoclave and heated to 60°C. Then, 8.7 mL of triethylaluminum, 11.4 mL of dicyclopentyldimethoxysilane, and 2.9 g of the prepolymerization catalyst obtained in (2) were charged to initiate polymerization. 75 minutes after the start of polymerization, the temperature was lowered to 50°C over 10 minutes (completion of first-stage polymerization).

[0090] The propylene polymer (b1) polymerized under the same conditions as in the first stage had an intrinsic viscosity [η] of 11 dl / g. After the temperature was lowered, hydrogen was continuously introduced to maintain a constant pressure of 3.3 MPaG, and polymerization was carried out for 151 minutes. Next, the vent valve was opened, and unreacted propylene was purged via an integrating flow meter (end of second-stage polymerization).

[0091] Thus, 51.8 kg of powdery propylene polymer Resin B-1 was obtained. To this Resin B-1, 2000 ppm of Irganox 1010 (manufactured by Ciba Specialty Chemicals Co., Ltd.), 2000 ppm of Irgaphos 168 (manufactured by Ciba Specialty Chemicals Co., Ltd.), and 1000 ppm of Sandstab P-EPQ (manufactured by Clariant Japan Co., Ltd.) were added as antioxidants, and 1000 ppm of calcium stearate was added as a neutralizer. The mixture was melt-kneaded in a twin-screw extruder to obtain pellet-shaped Resin B-1. The MFR of the finally obtained Resin B-1 was 1.2 g / 10 min. Furthermore, the mass fraction (proportion) of the propylene polymer (b1) produced in the first-stage polymerization in the finally obtained Resin B-1 calculated from the material balance was 25% by mass. The physical properties of the obtained Resin B-1 are shown in Table 1.

[0092] [Production of Resin B-2] (1) Preparation of Solid Catalyst Component 30 kg of the above magnesium compound (unground), 150 L of purified heptane (n-heptane), 4.5 L of silicon tetrachloride, and 5.4 L of di-n-butyl phthalate were added to a reactor equipped with a stirrer (internal volume 500 L) that had been thoroughly purged with nitrogen gas. The system was maintained at 90°C, and 144 L of titanium tetrachloride was added with stirring. The reaction was carried out at 110°C for 2 hours, after which the solid component was separated and washed with purified heptane at 80°C. Further, 228 L of titanium tetrachloride was added, and the reaction was carried out at 110°C for 2 hours. The solid component was then thoroughly washed with purified heptane to obtain a solid catalyst component.

[0093] (2) Preparation of Prepolymerization Catalyst 10 mmol of triethylaluminum, 2 mmol of dicyclopentyldimethoxysilane, and 1 mmol of the solid catalyst component obtained in (1) in terms of titanium atom were added to 200 mL of heptane. The internal temperature was maintained at 20°C, and propylene was continuously introduced with stirring. After 60 minutes, stirring was stopped, resulting in a prepolymerization catalyst in which 4.0 g of propylene had been polymerized per 1 g of solid catalyst.

[0094] (3) Main polymerization: 336 L of propylene was charged into a 600 L autoclave and heated to 60°C. Then, 8.7 mL of triethylaluminum, 11.4 mL of dicyclopentyldimethoxysilane, and 2.9 g of the prepolymerization catalyst obtained in (2) were charged to initiate polymerization. 45 minutes after the start of polymerization, the temperature was lowered to 50°C over 10 minutes (completion of first-stage polymerization).

[0095] The propylene polymer (b1) polymerized under the same conditions as in the first stage had an intrinsic viscosity [η] of 11 dl / g. After the temperature was lowered, hydrogen was continuously introduced to maintain a constant pressure of 2.1 MPaG, and polymerization was carried out for 240 minutes. Next, the vent valve was opened, and unreacted propylene was purged via an integrating flow meter (completion of the second stage polymerization).

[0096] Thus, 48 ​​kg of powdered resin B-2 was obtained. To this resin B-2, 2000 ppm of Irganox 1010 (manufactured by Ciba Specialty Chemicals Co., Ltd.), 2000 ppm of Irgaphos 168 (manufactured by Ciba Specialty Chemicals Co., Ltd.), and 1000 ppm of Sandstab P-EPQ (manufactured by Clariant Japan Co., Ltd.) were added as antioxidants, and 1000 ppm of calcium stearate was added as a neutralizer. The mixture was melt-kneaded in a twin-screw extruder to obtain pelletized resin B-2. The MFR of the resin B-2 finally obtained was 0.5 g / 10 min. Furthermore, the proportion of the propylene polymer (b1) produced in the first-stage polymerization in the finally obtained resin B-2 calculated from the mass balance was 17% by mass. The physical properties of the resulting resin B-2 are shown in Table 1.

[0097]

[0098] In Table 1, the "mass fraction (mass%)" indicates the mass fraction of the propylene polymer obtained in the first stage (corresponding to the propylene polymer (b1)) and the mass fraction of the propylene polymer obtained in the second stage (corresponding to the propylene polymer (b2)) in the production examples of Resins B-1 and B-2, which were determined from the amount of heat of reaction generated during polymerization.

[0099] [Examples 1 and 4] (Preparation of Unstretched Film) Using a resin composition consisting of 90 parts by mass of Resin A-1, which is a propylene polymer obtained in Production Example 1, and 10 parts by mass of Resin B-1, which is a propylene polymer, an unstretched film having a thickness of 30 μm was prepared using an unstretched film molding machine having a 600 mm wide single layer die connected to one extruder having a screw diameter of 75 mm under the following molding conditions: Resin temperature: 248°C Chill roll temperature: 30°C Molding speed: 150 m / min

[0100] Furthermore, test pieces of approximately A4 size (210 mm in the transverse (TD) direction x 290 mm in the extrusion (MD) direction) were prepared for various evaluations described below.

[0101] (Preparation of Laminated Film) The unstretched film formed above was cut to a width of 130 mm and set in a vacuum deposition apparatus equipped with a film payout machine and a winder. －２ After the film was evacuated to 100 Pa, it was wound around a cooled metal drum at -20°C. Aluminum oxide was heated and evaporated to deposit an inorganic oxide on the surface of the film that was in contact with the cooled metal drum, producing a laminated film. Test pieces approximately A4 size (210 mm in the transverse (TD) direction × 290 mm in the extrusion (MD) direction) were also prepared for various evaluations, which will be described later.

[0102] - Measurement and Evaluation - [Thickness of Inorganic Oxide Layer] For the laminate film, the thickness of the inorganic oxide layer was measured as follows. The obtained laminate film was cut with a microtome to expose the cross section. This cross section was observed using a scanning electron microscope (SEM) to measure the thickness of the inorganic oxide layer. SEM observation was performed using a Regulus 8220 manufactured by Hitachi High-Technologies Corporation, using a backscattered electron detector.

[0103] [Tensile Modulus] The tensile modulus (MPa) was measured according to the method of JIS K7161. The measurement was carried out at 23°C and 80°C in the extrusion (MD) direction of molding, and at 23°C in the perpendicular (TD) direction. It can be said that the higher the tensile modulus, the higher the rigidity.

[0104] [Haze] Measured in accordance with ASTM D-1003 (JIS K7105). The smaller the haze value, the more excellent the transparency.

[0105] [Gas Barrier Properties] (1) Water Vapor Permeability Using a water vapor permeability measuring device (manufactured by MOCON Corporation, model number: PERMATRAN-W3 / 33), the test temperature was 40°C, the relative humidity was 90%, and the moisture permeability area was 50 cm ２ Water vapor permeability (g / m ２ (2) Oxygen permeability Using a differential pressure gas permeability measuring device (Toyo Seiki Seisakusho Co., Ltd.), the oxygen permeability (cm ３ / m ２ ·day·atm) was measured.

[0106] [Wrinkles] The surface of the unstretched film side of the obtained laminate film was visually observed, and wrinkles in the TD direction were evaluated according to the following evaluation criteria. A rating of A or B in the following evaluation criteria can be said to be excellent in preventing wrinkles. -Evaluation criteria- A: The number of wrinkles was 2 or less, and wrinkle prevention was excellent. B: The number of wrinkles was 3 to 9, and this was at a level that presented no practical problems. C: The number of wrinkles was 10 or more, and wrinkle prevention was poor.

[0107] [Examples 2, 3, 5, and 6, Comparative Examples 1 to 6, and Reference Examples 1 to 6] Non-stretched films were produced in the same manner as in Example 1, except that Resin A and Resin B were changed to the resins shown in Table 2, Table 3, or Table 4, and laminated films were produced in the same manner as in Example 4. The obtained non-stretched films and laminated films were each subjected to various evaluations. The results are shown in Table 2, Table 3, or Table 4.

[0108]

[0109]

[0110]

[0111] In Tables 2 to 4, "-" means that the corresponding component is not contained or has not been measured or evaluated.

[0112] It can be seen that the unstretched films of Examples 1 to 3 are superior in wrinkle suppression and gas barrier properties compared to the unstretched films of Comparative Examples 1 to 3. It can also be seen that the laminate films of Examples 4 to 6 are superior in wrinkle suppression and gas barrier properties compared to the laminate films of Comparative Examples 4 to 6. Reference Examples 1 to 6 are reference examples because the intrinsic viscosity [η] of the propylene polymer (b2) contained in Resin B-1 is 0.99, which is outside the range of more than 1.5 dl / g and 2.5 dl / g.

Claims

1. A laminated film comprising: a non-stretched film formed from a polypropylene-based polymer composition containing 85 to 95% by mass of the following resin A and 5 to 15% by mass of the following resin B (wherein the total amount of the resin A and the resin B is 100% by mass); and a layer formed by vapor deposition of an inorganic oxide; Resin A: a propylene-based polymer having a melting point of 120 to 170°C and an intrinsic viscosity [η] in the range of more than 1.5 dl / g and not more than 5.0 dl / g; Resin B: a propylene polymer comprising 10 to 40 mass% of a propylene polymer (b1) having an intrinsic viscosity [η] in the range of 10 to 12 dl / g, and 60 to 90 mass% of a propylene polymer (b2) having an intrinsic viscosity [η] in the range of more than 1.5 dl / g and not more than 2.5 dl / g (the total amount of the propylene polymer (b1) and the propylene polymer (b2) is defined as 100 mass%).

2. The laminate film according to claim 1, wherein the inorganic oxide comprises aluminum oxide or silicon oxide.

3. The laminated film according to claim 1, wherein the layer formed by vapor deposition of the inorganic oxide has a thickness of 5 to 100 nm.

4. Oxygen permeability is 2000 (cm 3 / m 2 2. The laminated film according to claim 1, wherein the thermal expansion coefficient is 1 / day·atm or less.

5. The laminate film according to claim 1, having a tensile modulus of elasticity at 80°C of 800 MPa or more.

6. The laminate film according to claim 1, having a tensile modulus in the MD direction at 80°C of 800 MPa or more.

7. The laminated film according to any one of claims 1 to 6, further comprising a biaxially oriented polypropylene film.

8. A polypropylene polymer composition comprising 85 to 95% by mass of the following resin A, and 5 to 15% by mass of the following resin B (wherein the total amount of the resins A and B is 100% by mass); Resin A: a propylene polymer having a melting point of 120 to 170°C and an intrinsic viscosity [η] in the range of more than 1.5 dl / g and not more than 5.0 dl / g; Resin B: a propylene polymer comprising 10 to 40% by mass of a propylene polymer (b1) having an intrinsic viscosity [η] in the range of 10 to 12 dl / g, and 60 to 90% by mass of a propylene polymer (b2) having an intrinsic viscosity [η] in the range of more than 1.5 dl / g and not more than 2.5 dl / g (wherein the total amount of the propylene polymer (b1) and the propylene polymer (b2) is 100% by mass).

9. A non-oriented film formed from the polypropylene polymer composition according to claim 8.

10. A propylene polymer comprising: 10 to 40 mass% of a propylene polymer (b1) having an intrinsic viscosity [η] in the range of 10 to 12 dl / g; and 60 to 90 mass% of a propylene polymer (b2) having an intrinsic viscosity [η] in the range of more than 1.5 dl / g and not more than 2.5 dl / g (wherein the total amount of the propylene polymer (b1) and the propylene polymer (b2) is 100 mass%).

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