Polyolefin resin composition, method for producing polyolefin resin composition, film, and packaging bag

Abstract

Provided are a polyolefin resin composition that can be used to produce a film that is non-slip when wound up, a method for producing the polyolefin resin composition, a film containing the polyolefin resin composition, and a packaging bag containing the film. The polyolefin resin composition according to the present invention contains 80% by mass or more of a polyolefin resin and satisfies the following (1): (1) The infrared absorption spectrum of the film (A) obtained by molding the polyolefin resin composition is -1 The absorbance at the peak top appearing near 2330 cm -1 The absorbance ratio at the peak tops appearing in the vicinity is 1.24 or higher.

Description

[Technical Field]

[0001] The present invention relates to a polyolefin resin composition, a method for producing the polyolefin resin composition, a film containing the polyolefin resin composition, and a packaging bag containing the film. [Background technology]

[0002] BACKGROUND ART Films used as raw materials for packaging bags and the like are required to have excellent appearance, for example, to be free from defects such as fish eyes, foreign matter, and wrinkles, in order to give the package a beautiful appearance.

[0003] For example, Patent Document 1 discloses such a film, in which the integrated value of chemiluminescence intensity measured every second from the start of measurement to 300 seconds is 90,000 counts or less, and defects such as fisheyes are relatively reduced. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2022-155513 Summary of the Invention [Problem to be solved by the invention]

[0005] In the production of films, if the tension of the film is high when the film is wound into a roll, the film roll may become tight, wrinkles may form around the core, and the appearance of the film may be easily damaged. Therefore, it is required to wind the film while reducing the tension of the film.

[0006] However, when a film is wound up while reducing the tension of the film, if the film is slippery, the film may slip during winding, and the end surface of the roll may be prone to meandering. Therefore, there is a demand for a film that is less slippery during winding.

[0007] The present invention has been made in consideration of the above circumstances, and an object of the present invention is to provide a polyolefin-based resin composition that can be used to produce a film that is non-slip when wound up, a method for producing the polyolefin-based resin composition, a film containing the polyolefin-based resin composition, and a packaging bag containing the film. [Means for solving the problem]

[0008] The polyolefin resin composition according to the present invention contains a polyolefin resin in an amount of 80% by mass or more based on the polyolefin resin composition, and satisfies the following (1): (1) The infrared absorption spectrum of the film (A) obtained by molding the polyolefin resin composition is -1 The absorbance at the peak top appearing near 2330 cm -1 The absorbance ratio at the peak tops appearing in the vicinity is 1.24 or higher.

[0009] The method for producing a polyolefin-based resin composition according to the present invention is a method for producing the above-mentioned polyolefin-based resin composition, The method includes a step of melt-kneading the raw materials of the polyolefin resin composition for a residence time of 1 minute or more and 6 minutes or less.

[0010] The film according to the present invention contains the polyolefin resin composition described above.

[0011] The packaging bag according to the present invention includes the above-described film.

[0012] The film according to the present invention comprises a polyolefin resin composition, In the infrared absorption spectrum, 2020 cm -1 The absorbance at the peak top appearing near 2330 cm -1 The absorbance ratio at the peak top that appears near the peak is 1.24 or higher. [Effects of the Invention]

[0013] According to the present invention, it is possible to provide a polyolefin resin composition that can produce a film that does not slip when wound up, a method for producing the polyolefin resin composition, a film containing the polyolefin resin composition, and a packaging bag containing the film. DETAILED DESCRIPTION OF THE INVENTION

[0014] Hereinafter, embodiments of the present invention will be described, but the present invention is not limited to the following embodiments.

[0015] (Polyolefin resin composition) The polyolefin resin composition according to this embodiment satisfies the following (1). (1) The infrared absorption spectrum of the film (A) obtained by molding the polyolefin resin composition is -1 The absorbance at the peak top appearing near 2330 cm -1 The absorbance ratio at the peak tops appearing in the vicinity is 1.24 or higher.

[0016] From the viewpoint of producing a film that is less likely to slip when wound up, the absorbance ratio is preferably 1.27 or more, and more preferably 1.28 or more. -1 The peak appearing around is due to functional groups containing polar groups. It is presumed that the presence of such functional groups on the surface and inside of the film increases the adhesive strength between films, making them less likely to slip when wound up. In addition, from the viewpoint of suppressing adhesion of the films to each other, the absorbance ratio is preferably 2.00 or less, more preferably 1.50 or less. In this specification, "around" refers to ±10 cm -1 In this specification, the term "peak top" means a value at 2020 cm -1 Near or 2330cm -1 It refers to the peak with the greatest absorbance among the peaks that appear in the vicinity.

[0017] The absorbance ratio can be increased by, for example, increasing the wet tension of the film (B) described below, decreasing the thickness of the film (B), or decreasing the kneading temperature described below, and can be decreased by, for example, decreasing the wet tension of the film (B) described below, increasing the thickness of the film (B), or increasing the kneading temperature described below.

[0018] The infrared absorption spectrum can be measured using a Fourier transform infrared spectrophotometer (hereinafter referred to as FT-IR). Examples of FT-IR include transmission type FT-IR. In transmission type FT-IR, the peaks of the functional groups in the film are observed, so the absorbance ratio can be obtained as a similar value regardless of the film thickness, whether it is stretched, etc. For FT-IR, a commercially available device can be used, and a measurable film sample can be prepared and used for measurement according to the operating method of the device to be used.

[0019] From the viewpoint of producing a film that is less likely to slip when wound up, the polyolefin resin composition according to this embodiment preferably further satisfies the following (2). (2) The integrated chemiluminescence intensity of the film (A) obtained by dividing the integrated value of the chemiluminescence intensity from the start of measurement at a wavelength of 300 nm or more to 850 nm or less up to 300 seconds by the mass of the film (A) is 1.5 × 10 5 count / g or more 3.0×10 6 counts / g or less.

[0020] Chemiluminescence intensity is the intensity of weak light that is generated when molecules in a reaction system change from an excited state to a ground state during a chemical reaction, and can be measured using a chemiluminescence measuring device described below.

[0021] From the viewpoint of producing a film that is less likely to slip when wound up, the chemiluminescence integrated luminescence intensity is preferably 2.0 × 10 5 count / g or more 2.0×10 6counts / g or less, more preferably 3.0×10 5 count / g or more 5.0×10 5 counts / g or less.

[0022] The chemiluminescence integrated luminescence intensity can be increased by, for example, increasing the wet tension of the film (B) described below, decreasing the thickness of the film (B), increasing the kneading temperature described below, or shortening the residence time described below, and can be decreased by, for example, decreasing the wet tension of the film (B) described below, increasing the thickness of the film (B), decreasing the kneading temperature described below, or lengthening the residence time described below.

[0023] The integrated chemiluminescence luminescence intensity can be calculated by the following method.

[0024] First, the film (A) is cut into a piece 3 cm long x 3 cm wide, and three of the resulting film pieces are stacked together. The stacked film (A) is placed in the sample chamber of a chemiluminescence measuring device having a photomultiplier tube as the detection element, which has been preheated to 150°C. Nitrogen gas is supplied to the sample chamber at 50 mL / min, and the chemiluminescence emission intensity from 300 nm to 850 nm is measured under a nitrogen gas atmosphere. The integrated value of the chemiluminescence emission intensity measured every second from the start of measurement until 300 seconds is calculated.

[0025] The integrated value of the chemiluminescence emission intensity is then divided by the mass of the overlaid film (A) to determine the integrated chemiluminescence emission intensity.

[0026] [Polyolefin resin]

[0027] The polyolefin resin composition according to the present embodiment contains a polyolefin resin. The polyolefin resin composition contains 80% by mass or more of the polyolefin resin based on the polyolefin resin composition. From the viewpoint of producing a film that is not easily slippery when wound up, the content of the polyolefin resin is preferably 90% by mass or more, and more preferably 95% by mass or more, based on the polyolefin resin composition.

[0028] The polyolefin resin is a resin containing an olefin polymer.

[0029] Examples of polyolefin resins contained in the polyolefin resin composition include polyethylene resins, polypropylene resins, etc. Among these, from the viewpoint of producing a film in which meandering of the roll end surface is reduced when wound into a roll, the polyolefin resin is preferably at least one of polyethylene resins and polypropylene resins, and more preferably polyethylene resins.

[0030] <Polyethylene resin> The polyethylene resin is a resin containing an ethylene polymer.

[0031] An ethylene-based polymer is a polymer containing more than 50 mol% of monomer units derived from ethylene. Examples of ethylene-based polymers include ethylene homopolymers, copolymers of ethylene and α-olefins, and copolymers of ethylene and α-olefins substituted with alicyclic compounds. The ethylene-based polymer may also be a mixture of an ethylene homopolymer and a copolymer of ethylene and α-olefins. The amount of monomer units derived from α-olefins in the ethylene-based polymer is not particularly limited and may be, for example, 4.0 mol% or more and 20 mol% or less.

[0032] Examples of ethylene homopolymers include high-pressure low-density polyethylene (LDPE), which is produced by high-pressure radical polymerization using a radical initiator. High-pressure low-density polyethylene (LDPE) is a polymer in which repeating ethylene units are randomly bonded to form a branched structure. High-pressure low-density polyethylene (LDPE) has a density of, for example, 910 to 935 kg / m 3 may be.

[0033] Examples of copolymers of ethylene and α-olefins include linear low-density polyethylene having crystallinity, and elastomers of copolymers of ethylene and α-olefins having low crystallinity and rubber-like elastic properties.

[0034] The density of the linear low-density polyethylene is, for example, 900 to 940 kg / m 3 The density of the elastomer of the copolymer of ethylene and α-olefin may be, for example, 860 to 900 kg / m 3 may be.

[0035] Examples of the α-olefin include α-olefins having 3 to 10 carbon atoms. Examples of the α-olefins having 3 to 10 carbon atoms include propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene, 1-decene, and 3-methyl-1-butene. Preferred are α-olefins having 4 to 10 carbon atoms, and more preferred are 1-butene, 1-hexene, and 1-octene.

[0036] Examples of copolymers of ethylene and α-olefins include ethylene-1-butene copolymers, ethylene-1-hexene copolymers, ethylene-1-octene copolymers, ethylene-1-decene copolymers, ethylene-(3-methyl-1-butene) copolymers, etc. The copolymer of ethylene and α-olefins may be one of these copolymers alone or a mixture of two or more thereof.

[0037] Examples of α-olefins substituted with alicyclic compounds include vinylcyclohexane.

[0038] The melt flow rate (MFR) of the ethylene polymer is preferably 0.5 g / 10 min or more and 50 g / 10 min or less, more preferably 1 g / 10 min or more and 30 g / 10 min or less, and even more preferably 1 g / 10 min or more and 20 g / 10 min or less.

[0039] The melt flow rate (MFR) of an ethylene polymer is measured by Method A under conditions of a temperature of 190°C and a load of 2.16 kg in accordance with the method specified in JIS K7210-1:2014 and K7210-2:2014.

[0040] The ethylene polymer can be produced by a known polymerization method using a known polymerization catalyst.

[0041] Examples of polymerization catalysts include homogeneous catalyst systems such as metallocene catalysts, Ziegler catalyst systems, and Ziegler-Natta catalyst systems. Examples of homogeneous catalyst systems include a catalyst system consisting of a Group 4 transition metal compound having a cyclopentadienyl ring and an alkylaluminoxane, a catalyst system consisting of a Group 4 transition metal compound having a cyclopentadienyl ring, a compound that reacts with the metal compound to form an ionic complex, and an organoaluminum compound, a catalyst system in which inorganic particles such as silica or clay minerals are supported and modified with catalytic components such as a Group 4 transition metal compound having a cyclopentadienyl ring, a compound that forms an ionic complex, and an organoaluminum compound, and a prepolymerization catalyst system prepared by prepolymerizing ethylene or an α-olefin in the presence of the above catalyst system.

[0042] Furthermore, a radical initiator can be used as a polymerization catalyst for high-pressure low-density polyethylene (LDPE).

[0043] <Polypropylene resin> The polypropylene resin is a resin containing a propylene polymer.

[0044] A propylene-based polymer is a polymer containing more than 50% by mass of monomer units derived from propylene. Examples of propylene-based polymers include propylene homopolymers, random copolymers of propylene and monomers other than propylene, and heterophasic propylene polymer materials. A polypropylene-based resin may contain only one type of propylene-based polymer, or may contain two or more types of propylene-based polymers.

[0045] From the viewpoint of improving the rigidity and impact resistance of the molded article, the polypropylene-based resin preferably contains, as a propylene-based polymer, at least one selected from the group consisting of a propylene homopolymer, a random copolymer of propylene and a monomer other than propylene, and a heterophasic propylene polymer material.

[0046] The propylene homopolymer can be produced, for example, by carrying out a polymerization step in which propylene is polymerized using a polymerization catalyst.

[0047] Examples of the polymerization catalyst include Ziegler catalysts; Ziegler-Natta catalysts; catalysts containing a compound of a transition metal of Group 4 of the periodic table having a cyclopentadienyl ring and an alkylaluminoxane; catalysts containing a compound of a transition metal of Group 4 of the periodic table having a cyclopentadienyl ring, a compound that reacts with the transition metal compound to form an ionic complex, and an organoaluminum compound; and modified catalysts in which a catalyst component (a compound of a transition metal of Group 4 of the periodic table having a cyclopentadienyl ring, a compound that forms an ionic complex, an organoaluminum compound, etc.) is supported on inorganic particles (silica, clay minerals, etc.).

[0048] Examples of the polymerization catalyst include catalysts described in JP-A-61-218606, JP-A-5-194685, JP-A-7-216017, JP-A-9-316147, JP-A-10-212319, JP-A-2004-182981, JP-A-2010-168545, and JP-A-2011-246699.

[0049] Furthermore, a polymer obtained by prepolymerizing propylene in the presence of the above polymerization catalyst can also be used as the polymerization catalyst.

[0050] Examples of polymerization methods include bulk polymerization, solution polymerization, and gas phase polymerization. Here, bulk polymerization refers to a method in which polymerization is carried out using an olefin that is liquid at the polymerization temperature as a medium. Solution polymerization refers to a method in which polymerization is carried out in an inert hydrocarbon solvent such as propane, butane, isobutane, pentane, hexane, heptane, or octane. Gas phase polymerization refers to a method in which gaseous monomers are used as a medium and the gaseous monomers are polymerized in the medium.

[0051] The polymerization method may be, for example, a batch method, a continuous method, or a combination thereof. The polymerization method may be a multi-stage method in which a plurality of polymerization reactors are connected in series.

[0052] From the viewpoint of industrial and economical excellence, the polymerization method is preferably a continuous gas phase polymerization method or a bulk-gas phase polymerization method in which bulk polymerization and gas phase polymerization are carried out continuously.

[0053] Various conditions in the polymerization step (polymerization conditions such as polymerization temperature, polymerization pressure, monomer concentration, catalyst input amount, and polymerization time) may be appropriately determined depending on the molecular structure of the target polymer.

[0054] In the method for producing a propylene homopolymer, other steps may be carried out before or after the polymerization step. For example, after the polymerization step, the polymer may be dried at a temperature equal to or lower than the melting point of the polymer, as necessary, to remove residual solvent contained in the polymer and ultralow molecular weight oligomers produced as by-products during the production. Examples of drying methods include those described in JP-A-55-75410 and JP-A-2565753.

[0055] The random copolymer of propylene and a monomer other than propylene contains monomer units derived from propylene and monomer units derived from a monomer other than propylene. In the random copolymer, the content of the monomer units derived from a monomer other than propylene is preferably 0.01% by mass or more and 30% by mass or less, more preferably 0.1% by mass or more and 20% by mass or less, relative to the total mass of the copolymer (100% by mass).

[0056] Examples of monomers other than propylene include ethylene and α-olefins having 4 to 12 carbon atoms. In this specification, α-olefins are aliphatic unsaturated hydrocarbons having a carbon-carbon unsaturated double bond at the α-position. Examples of α-olefins having 4 to 12 carbon atoms include 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, 1-dodecene, 4-methyl-1-pentene, and 4-methyl-1-hexene.

[0057] The monomer other than propylene is preferably at least one selected from the group consisting of ethylene and α-olefins having 4 to 10 carbon atoms, more preferably at least one selected from the group consisting of ethylene, 1-butene, 1-hexene, and 1-octene, and even more preferably at least one selected from the group consisting of ethylene and 1-butene.

[0058] Examples of random copolymers of propylene and a monomer other than propylene include propylene-ethylene random copolymers, propylene-1-butene random copolymers, propylene-1-hexene random copolymers, propylene-1-octene random copolymers, propylene-ethylene-1-butene random copolymers, propylene-ethylene-1-hexene random copolymers, and propylene-ethylene-1-octene random copolymers.

[0059] A random copolymer of propylene and a monomer other than propylene can be produced, for example, by polymerizing propylene and a monomer other than propylene in accordance with the polymerization catalyst, polymerization method, polymerization system, and polymerization conditions that can be used in the production of the above-mentioned propylene homopolymer.

[0060] The heterophasic propylene polymer material is a mixture containing a polymer I containing monomer units derived from propylene, and a polymer II containing monomer units derived from at least one α-olefin selected from the group consisting of ethylene and α-olefins having 4 to 12 carbon atoms and monomer units derived from propylene.

[0061] The heterophasic propylene polymer material can be produced, for example, by carrying out a first polymerization step of polymerizing polymer I and a second polymerization step of polymerizing polymer II. These polymerization steps can be carried out using the same polymerization catalyst, polymerization method, polymerization system, and polymerization conditions as those usable in the production of the above-mentioned propylene homopolymer.

[0062] The heterophasic propylene polymer material may be such that the sum of polymer I and polymer II contained in the heterophasic propylene polymer material is 100% by mass relative to the total mass of the heterophasic propylene polymer material (100% by mass).

[0063] Polymer I may contain 70% by mass or more of monomer units derived from propylene (where the total mass of Polymer I is 100% by mass). Polymer I may be, for example, a propylene homopolymer, or may contain monomer units derived from a monomer other than propylene. When Polymer I contains monomer units derived from a monomer other than propylene, the content thereof is usually 0.01% by mass or more and 30% by mass or less, relative to the total mass of Polymer I (100% by mass).

[0064] Examples of the monomer other than propylene include ethylene and α-olefins having 4 or more carbon atoms. Examples of the α-olefins having 4 or more carbon atoms include 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, 1-dodecene, 4-methyl-1-pentene, and 4-methyl-1-hexene.

[0065] The monomer other than propylene is preferably at least one selected from the group consisting of ethylene and α-olefins having 4 to 10 carbon atoms, more preferably at least one selected from the group consisting of ethylene, 1-butene, 1-hexene, and 1-octene, and even more preferably at least one selected from the group consisting of ethylene and 1-butene.

[0066] Examples of polymer I containing monomer units derived from a monomer other than propylene include propylene-ethylene copolymer, propylene-1-butene copolymer, propylene-1-hexene copolymer, propylene-1-octene copolymer, propylene-ethylene-1-butene copolymer, propylene-ethylene-1-hexene copolymer, and propylene-ethylene-1-octene copolymer.

[0067] Polymer I is preferably a propylene homopolymer, a propylene-ethylene copolymer, a propylene-1-butene copolymer, or a propylene-1-hexene copolymer, and more preferably a propylene homopolymer.

[0068] The content of polymer I is usually 30% by mass or more and 99% by mass or less, preferably 50% by mass or more and 95% by mass or less, and more preferably 60% by mass or more and 90% by mass or less, based on the total mass of the heterophasic propylene polymerization material (100% by mass).

[0069] As described above, polymer II contains monomer units derived from at least one α-olefin selected from the group consisting of ethylene and α-olefins having 4 to 12 carbon atoms, and monomer units derived from propylene. Examples of α-olefins having 4 to 12 carbon atoms include 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, 1-dodecene, 4-methyl-1-pentene, and 4-methyl-1-hexene.

[0070] Polymer II preferably contains 30% by mass or more of monomer units derived from at least one α-olefin selected from the group consisting of ethylene and α-olefins having 4 to 12 carbon atoms, and also contains monomer units derived from propylene (where the total mass of Polymer II is taken as 100% by mass).

[0071] In polymer II, the content of monomer units derived from at least one α-olefin selected from the group consisting of ethylene and α-olefins having 4 to 12 carbon atoms is usually 1% by mass or more and 80% by mass or less, preferably 20% by mass or more and 70% by mass or less, and more preferably 30% by mass or more and 60% by mass or less (where the total mass of polymer II is taken as 100% by mass).

[0072] In Polymer II, the at least one α-olefin selected from the group consisting of ethylene and α-olefins having 4 to 12 carbon atoms is preferably at least one selected from the group consisting of ethylene and α-olefins having 4 to 10 carbon atoms, more preferably at least one selected from the group consisting of ethylene, 1-butene, 1-hexene, 1-octene, and 1-decene, and even more preferably at least one selected from the group consisting of ethylene and 1-butene.

[0073] Examples of polymer II include propylene-ethylene copolymer, propylene-ethylene-1-butene copolymer, propylene-ethylene-1-hexene copolymer, propylene-ethylene-1-octene copolymer, propylene-ethylene-1-decene copolymer, propylene-1-butene copolymer, propylene-1-hexene copolymer, propylene-1-octene copolymer, propylene-1-decene copolymer, etc. Among these, polymer II is preferably a propylene-ethylene copolymer, a propylene-1-butene copolymer, or a propylene-ethylene-1-butene copolymer, and more preferably a propylene-ethylene copolymer.

[0074] The content of polymer II is usually 1% by mass or more and 70% by mass or less, preferably 5% by mass or more and 50% by mass or less, and more preferably 10% by mass or more and 40% by mass or less, relative to the total mass of the heterophasic propylene polymerization material (100% by mass).

[0075] Examples of heterophasic propylene polymer materials include (propylene)-(propylene-ethylene) polymer materials, (propylene)-(propylene-ethylene-1-butene) polymer materials, (propylene)-(propylene-ethylene-1-hexene) polymer materials, (propylene)-(propylene-ethylene-1-octene) polymer materials, (propylene)-(propylene-1-butene) polymer materials, (propylene)-(propylene-1-hexene) polymer materials, (propylene)-(propylene-1-octene) polymer materials, and (propylene)-(propylene-1-decene) polymer materials. materials, (propylene-ethylene)-(propylene-ethylene) polymerization materials, (propylene-ethylene)-(propylene-ethylene-1-butene) polymerization materials, (propylene-ethylene)-(propylene-ethylene-1-hexene) polymerization materials, (propylene-ethylene)-(propylene-ethylene-1-octene) polymerization materials, (propylene-ethylene)-(propylene-ethylene-1-decene) polymerization materials, (propylene-ethylene)-(propylene-1-butene) polymerization materials, (propylene-ethylene)-(propylene-1-hexene) polymerization materials, (propylene-ethylene) (propylene)-(propylene-1-octene) polymerization materials, (propylene-ethylene)-(propylene-1-decene) polymerization materials, (propylene-1-butene)-(propylene-ethylene) polymerization materials, (propylene-1-butene)-(propylene-ethylene-1-butene) polymerization materials, (propylene-1-butene)-(propylene-ethylene-1-hexene) polymerization materials, (propylene-1-butene)-(propylene-ethylene-1-octene) polymerization materials, (propylene-1-butene)-(propylene-ethylene-1-decene) polymerization materials, (propylene-1-butene)-(propylene-ethylene-1-decene) polymerization materials, (propylene-1-butene)-( (propylene-1-butene) polymerization materials, (propylene-1-butene)-(propylene-1-hexene) polymerization materials, (propylene-1-butene)-(propylene-1-octene) polymerization materials, (propylene-1-butene)-(propylene-1-decene) polymerization materials, (propylene-1-hexene)-(propylene-1-hexene) polymerization materials, (propylene-1-hexene)-(propylene-1-octene) polymerization materials, (propylene-1-hexene)-(propylene-1-decene) polymerization materials, (propylene-1-octene)-(propylene-1-octene) polymerization materials,(propylene-1-octene)-(propylene-1-decene) polymer materials, etc.

[0076] Here, the expression "(propylene)-(propylene-ethylene) polymer material" means "a heterophasic propylene polymer material in which polymer I is a propylene homopolymer and polymer II is a propylene-ethylene copolymer." The same applies to other similar expressions.

[0077] The heterophasic propylene polymeric material is preferably a (propylene)-(propylene-ethylene) polymeric material, a (propylene)-(propylene-ethylene-1-butene) polymeric material, a (propylene-ethylene)-(propylene-ethylene) polymeric material, a (propylene-ethylene)-(propylene-ethylene-1-butene) polymeric material, or a (propylene-1-butene)-(propylene-1-butene) polymeric material, and more preferably a (propylene)-(propylene-ethylene) polymeric material.

[0078] From the viewpoint of improving the molding processability of the polypropylene resin composition, the melt flow rate (MFR) of the propylene polymer is preferably 1 g / 10 min or more and 300 g / 10 min or less, and more preferably 10 g / 10 min or more and 200 g / 10 min or less.

[0079] The melt flow rate (MFR) of a propylene polymer is measured by Method A under conditions of a temperature of 230°C and a load of 2.16 kg in accordance with the method specified in JIS K7210-1:2014 and K7210-2:2014.

[0080] From the viewpoint of producing a film that is less likely to slip when wound up, the polyolefin resin composition according to this embodiment is preferably a film (B) containing a polyolefin resin as a raw material for the polyolefin resin composition.

[0081] The polyolefin resin contained in the film (B) may be the above-mentioned polyolefin resin.

[0082] The film (B) may be a single-layer film or a multi-layer film having two or more layers including at least one layer containing the polyolefin resin.

[0083] From the viewpoint of producing a film that is less likely to slip when wound up, at least one surface of the film (B) is preferably treated, and more preferably both surfaces are treated.

[0084] The film (B) has been subjected to treatments such as corona treatment, plasma treatment, ozone treatment, etc. From the viewpoint of producing a film that is less slippery when wound up, the film (B) has preferably been subjected to at least one treatment selected from the group consisting of corona treatment, plasma treatment, and ozone treatment, more preferably corona treatment. When surface treatments are applied to both sides of the film (B), the film (B) may be subjected to the same treatment on each side, or different treatments may be applied to each side.

[0085] 2330cm -1The peak appearing around 2330 cm is detected, for example, in the infrared absorption spectrum of a film (A) obtained by molding a polyolefin resin composition obtained by melt-kneading a film (B) that has been subjected to the above-mentioned surface treatment. Functional groups containing polar groups are present on the surface of the surface-treated film. When such a film is melt-kneaded, it is subjected to heat sufficient to melt the resin. This can lead to at least one of the following: (i) the functional groups are dispersed not only on the surface of the film but also inside the film due to melt-kneading; (ii) the functional groups react with each other or with other components due to heating or some other factor during melt-kneading and / or subsequent film formation; or (iii) if the melt-kneaded film contains additives, for example, the additives described below may react with other components or the functional groups due to heating or some other factor during melt-kneading and / or subsequent film formation. This can lead to the appearance of a peak at 2330 cm in the infrared absorption spectrum of film (A). -1 It is presumed that the intensity of the peak appearing near 2330 cm becomes higher, that is, the ratio of the absorbances increases. Note that, simply by subjecting the surface of the film (A) to a surface treatment such as a corona treatment, the above events (i) to (iii) do not occur. -1 It is presumed that the intensity of the peak appearing in the vicinity becomes smaller, that is, the ratio of the absorbances becomes smaller.

[0086] When the polyolefin resin composition according to this embodiment contains the film (B) as a raw material, it preferably further satisfies the following (3) from the viewpoint of producing a film that is not easily slippery when wound up. (3) The wet tension of at least one of the surfaces of the film (B) is 32 mN / m or more and 60 mN / m or less.

[0087] From the viewpoint of producing a film that is not slippery when wound up, the wet tension of at least one of the surfaces of the film (B) is preferably 32 mN / m or more and 60 mN / m or less, more preferably 35 mN / m or more and 50 mN / m or less. The wet tension can be measured in accordance with JIS K 6768-1999. When both surfaces of the film (B) are treated, the wet tensions of the respective surfaces may be the same or different.

[0088] In one aspect, the polyolefin-based resin composition according to the present embodiment comprises a film (B) containing a polyolefin-based resin as a raw material of the polyolefin-based resin composition, and the film (B) has been subjected to at least one treatment selected from the group consisting of a corona treatment, a plasma treatment, and an ozone treatment, and further satisfies the above-mentioned (3).

[0089] From the viewpoint of producing a film with reduced meandering of the roll end surface when wound into a roll, the film (B) is preferably at least one of a resin film recovered from the market and a resin film recovered from within a process, and more preferably a resin film recovered from within a process. In this specification, "resin film recovered from the market" refers to a resin film derived from materials discarded from households, sorted and removed from plastic waste such as packaging, etc. In addition, in this specification, "resin film recovered from within a process" refers to a resin film generated in a process for producing a resin molded product, a resin material used to obtain the molded product, and a resin film derived from the obtained molded product.

[0090] [Other additives] The polyolefin resin composition according to the present embodiment may contain other additives as needed, such as pigments, dyes, inorganic fillers, neutralizing agents, antioxidants, lubricants, copper inhibitors, antifogging agents, antistatic agents, processing stabilizers, UV absorbers, light stabilizers, nucleating agents, clarifying nucleating agents, processing aids, metal soaps, foaming agents, antibacterial agents, plasticizers, flame retardants, flame retardant aids, polyolefin crosslinking agents, polyolefin crosslinking aids, brightness enhancers, flowability modifiers, and crystallization retarders.

[0091] (Method of producing polyolefin resin composition) The method for producing a polyolefin-based resin composition according to this embodiment is the method for producing a polyolefin-based resin composition according to the above-described embodiment, and includes a step of melt-kneading the raw materials of the polyolefin-based resin composition for a residence time of 1 minute or more and 6 minutes or less.

[0092] From the viewpoint of producing a film that is not easily slippery when wound up, the residence time is preferably 2 minutes or more and 5.5 minutes or less, and more preferably 3 minutes or more and 5 minutes or less.

[0093] Examples of the kneader used for the kneading include a single-screw extruder, a twin-screw extruder, a Banbury mixer, and a heat roll.

[0094] The kneading temperature is preferably 130° C. or higher and 250° C. or lower, more preferably 140° C. or higher and 240° C. or lower, from the viewpoint of imparting slipperiness while suppressing adhesion of the films to each other.

[0095] In the kneading, the rotation speed of the screw provided in the kneader is preferably 10 rpm or more and 200 rpm or less, more preferably 30 rpm or more and 150 rpm or less, from the viewpoint of preventing the films from sticking to each other and imparting slipperiness.

[0096] The raw material of the polyolefin resin composition may be the film (B) in the polyolefin resin composition according to the present embodiment.

[0097] The above step may be carried out under a nitrogen atmosphere or an air atmosphere.

[0098] The method for producing the polyolefin resin composition according to this embodiment is carried out, for example, by the following method.

[0099] The film (B) and, if necessary, other additives in the polyolefin resin composition according to the present embodiment are fed to a kneader and melt-kneaded under a nitrogen atmosphere at a temperature of 150°C and a rotation speed of 50 rpm for a residence time of 5 minutes to obtain a polyolefin resin composition. The film (B) may be crushed as necessary before use.

[0100] (film) The film according to this embodiment contains the polyolefin resin composition according to this embodiment.

[0101] The film according to the present embodiment contains a polyolefin resin composition, and has an infrared absorption spectrum of 2020 cm -1 The absorbance at the peak top appearing near 2330 cm -1 The absorbance ratio at the peak top that appears near the peak is 1.24 or higher.

[0102] The thickness of the film is preferably 10 μm or more and 200 μm or less, more preferably 20 μm or more and 150 μm or less, from the viewpoint of preventing adhesion of films to each other and imparting slipperiness. The absorbance ratio is not derived from the film thickness, as described above. Therefore, the thickness of the film used for measuring the infrared absorption spectrum is not particularly limited and may be within the above range or may be 100 μm.

[0103] The film according to this embodiment may be a single-layer film, or may be a multi-layer film including at least one layer containing the polyolefin resin composition according to this embodiment.

[0104] When the film according to the present embodiment is a single-layer film, it can be produced by, for example, inflation molding, T-die molding, calendar molding, blow molding, sheet molding, etc. When the film according to the present embodiment is a multilayer film, it can be produced by, for example, a multilayer film formation method such as coextrusion, extrusion lamination, thermal lamination, or dry lamination.

[0105] The film according to this embodiment may be subjected to treatment such as corona discharge treatment, flame treatment, plasma treatment, or ozone treatment.

[0106] The film according to the present embodiment may be a stretched film or an unstretched film. The stretched film may be a uniaxially stretched film or a biaxially stretched film. The stretched film can be stretched by a known method.

[0107] In one aspect, the film according to this embodiment is obtained by molding a polyolefin resin composition under press conditions of a temperature of 230° C. and a pressure of 10 MPa.

[0108] (packaging bag) The packaging bag according to this embodiment includes the film according to this embodiment.

[0109] The packaging bag according to this embodiment may be in any known form, such as a pillow package, a three-side sealed package, a four-side sealed package, a gusset package, or a standing pouch.

[0110] The packaging bag according to this embodiment can be produced by a known method. For example, the film can be formed into a packaging bag by folding the film into the shape of a bag and heat sealing it.

[0111] The packaging bag according to this embodiment is used for packaging any object to be packaged, such as food, clothing, miscellaneous goods, etc.

[0112] The polyolefin resin composition, the method for producing the polyolefin resin composition, the film, and the packaging bag according to the present embodiment are not limited to the above embodiment, and various modifications are possible without departing from the spirit of the present invention. Furthermore, the configurations, methods, etc. of embodiments other than those described above may be arbitrarily adopted and combined, and the configurations, methods, etc. of one embodiment described above may be applied to the configurations, methods, etc. of other embodiments described above.

[0113] The present invention includes the following aspects. [1] A polyolefin-based resin composition containing a polyolefin-based resin in an amount of 80% by mass or more based on the polyolefin-based resin composition, and satisfying the following (1): (1) The infrared absorption spectrum of the film (A) obtained by molding the polyolefin resin composition is -1 The absorbance at the peak top appearing near 2330 cm -1 The absorbance ratio at the peak tops appearing in the vicinity is 1.24 or higher. [2] The polyolefin resin composition according to [1], which further satisfies the following (2): (2) The integrated chemiluminescence intensity of the film (A) obtained by dividing the integrated value of the chemiluminescence intensity from the start of measurement at a wavelength of 300 nm or more to 850 nm or less up to 300 seconds by the mass of the film (A) is 1.5 × 10 5 count / g or more 3.0×10 6 counts / g or less. [3] The polyolefin resin composition according to [1] or [2], wherein the content of the polyolefin resin is 90% by mass or more based on the polyolefin resin. [4] The polyolefin resin composition according to any one of [1] to [3], wherein the polyolefin resin is at least one of polyethylene and polypropylene. [5] The raw material of the polyolefin resin composition includes a film (B) containing a polyolefin resin, The polyolefin resin composition according to any one of [1] to [4], wherein the film (B) has been subjected to at least one treatment selected from the group consisting of a corona treatment, a plasma treatment, and an ozone treatment. [6] The polyolefin resin composition according to [5], which further satisfies the following (3): (3) The wet tension of at least one of the surfaces of the film (B) is 32 mN / m or more and 60 mN / m or less. [7] The polyolefin resin composition according to [5] or [6], wherein the film (B) is at least one of a resin film collected from the market and a resin film collected from within a process. [8] A method for producing the polyolefin resin composition according to any one of [1] to [7], A method for producing a polyolefin resin composition, comprising a step of melt-kneading raw materials for the polyolefin resin composition for a residence time of 1 minute or more and 6 minutes or less. [9] A film comprising the polyolefin resin composition according to any one of [1] to [7].

[10] A packaging bag comprising the film described in [9].

[11] A polyolefin resin composition, In the infrared absorption spectrum, 2020 cm -1 The absorbance at the peak top appearing near 2330 cm -1 A film having an absorbance ratio of 1.24 or more at the peak tops appearing near the

[12] The film according to [9], which is a stretched film or an unstretched film.

[13] The film according to

[11] , which is a stretched film or an unstretched film.

[14] The film according to

[12] , wherein the stretched film is a uniaxially stretched film or a biaxially stretched film.

[15] The film according to

[13] , wherein the stretched film is a uniaxially stretched film or a biaxially stretched film.

[16] The film according to [9] or

[12] , obtained by molding a polyolefin resin composition under press conditions of a temperature of 230°C and a pressure of 10 MPa.

[17] The film according to

[11] or

[13] , obtained by molding a polyolefin resin composition under press conditions of a temperature of 230°C and a pressure of 10 MPa. [Example]

[0114] The present invention will be described in more detail below using examples and comparative examples, but the present invention is not limited to the following examples. The measured values ​​of each item in the examples and comparative examples were measured by the following methods.

[0115] (Method of measuring physical properties) [Melt flow rate (MFR, unit: g / 10 min)] The MFR was measured under conditions of a temperature of 230°C and a load of 2.16 kg in accordance with Method A described in JIS K7210-1:2014.

[0116] [Film thickness (unit: μm)] The film thickness was measured using a contact type film thickness meter in accordance with Method A described in JIS K7130-1999.

[0117] [Density (unit: kg / m 3 )] The density was measured according to Method A described in JIS K7112-1980.

[0118] [Wet tension (unit: mN / m)] Wet tension was measured according to JIS K6768-1999. Specifically, a mixture for wetting tension testing (31 to 54 mN / m, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) was first applied to the surface of film (B), and the state of the liquid film was visually observed after 2 seconds. If a liquid film was formed on the surface of film (B), the same procedure was repeated using the mixture with a higher wet tension. Alternatively, if no liquid film was formed on the measurement surface of film (B), the same procedure was repeated using the mixture with a lower wet tension. Finally, the wet tension value indicated for the mixture used when a liquid film began to form was taken as the wet tension of the surface of film (B). Note that if a liquid film was not formed even when using the mixture with a wet tension of 31 mN / m, the wet tension of the measurement surface of film (B) was determined to be less than 31 mN / m.

[0119] [Measurement of infrared absorption spectrum] The infrared absorption spectrum was measured by the following method. Specifically, a Fourier transform infrared spectrophotometer (FT-IR, transmission type, manufactured by Shimadzu Corporation, model name: IR-Spirit, sample chamber window: KBr) was used, with 16 accumulations and a resolution of 4.0 cm. -1 The infrared absorption spectrum of the film (A) was measured under the conditions of -1 The absorbance at the peak top appearing near 2330 cm -1 The ratio of absorbance at the peak top appearing around 2330 cm -1 / 2020cm -1 The ratio was calculated.

[0120] [Cumulative chemiluminescence intensity (unit: count / g)] The integrated chemiluminescence intensity was measured by the following method. Specifically, first, film (A) was cut into a 3 cm x 3 cm piece, three of the resulting film pieces were stacked, and the mass of the stacked film (A) was measured. Next, the stacked film (A) was placed in the sample chamber of a chemiluminescence measuring device having a photomultiplier tube as a detection element that had been preheated to 150°C. Nitrogen gas was supplied to the sample chamber at 50 mL / min, and the chemiluminescence intensity from 300 nm to 850 nm was measured under a nitrogen gas atmosphere. The integrated value of the chemiluminescence intensity measured every second from the start of measurement until 300 seconds was calculated. The integrated value of the chemiluminescence intensity was then divided by the mass of the stacked film (A) to calculate the integrated chemiluminescence intensity.

[0121] [Static friction coefficient] The static friction coefficient was measured by the following method: Specifically, the static friction coefficient of the film (A) was measured using a friction coefficient measuring device (TR-2, manufactured by Toyo Seiki Seisakusho Co., Ltd.) under the horizontal method with a thread load of 1000 g and a test speed of 700 mm / min.

[0122] Example 1 [Production of unprocessed film] Low-density polyethylene (Sumikathen® F200-0 (Sumitomo Chemical Co., Ltd., production method: high-pressure radical polymerization, ethylene-derived monomer units: 100 mol%, density: 922 kg / m 3 The resulting untreated film had a wet tension of less than 31 mN / m on both sides.

[0123] [Production of film (B)] One side of the untreated film was subjected to corona treatment using a corona treatment machine (manufactured by Softal Corporation, Japan) under the following conditions so that the wet tension was 39 mN / m, thereby obtaining a film (B) that is a raw material for a polyolefin resin composition. <Conditions for corona treatment> Distance between electrode and film surface: 1.5 mm Roll speed: 30m / min Processing power: 150W Processing count: 1 time

[0124] [Production of polyolefin resin composition] The above film (B) was shredded, and the shredded film (B) was supplied to a Labo Plastomill (manufactured by Toyo Seiki Seisakusho, Ltd.) and melt-kneaded under a nitrogen atmosphere at a temperature of 150°C and a screw rotation speed of 60 rpm for a residence time of 5 minutes to obtain a polyolefin resin composition.

[0125] [Production of film (A)] Using a heat press molding machine, the polyolefin resin composition was preheated at 230°C for 5 minutes, pressurized to 10 MPa, held for 5 minutes, and cooled at 30°C for 5 minutes to obtain a film (A) having a thickness of 100 µm. -1 / 2020cm -1 The results of the ratio, integrated chemiluminescence intensity, and static friction coefficient are shown in Table 1.

[0126] Example 2 A film (A) was obtained in the same manner as in Example 1, except that a corona treatment was performed on both sides of the untreated film so that the wet tension was 39 mN / m each to obtain a film (B) that would be a raw material for the polyolefin resin composition. -1 / 2020cm -1 The results of the ratio, integrated chemiluminescence intensity, and static friction coefficient are shown in Table 1.

[0127] Example 3 A film (A) was obtained in the same manner as in Example 1, except that one side of the untreated film was subjected to a corona treatment under the following conditions so that the wet tension was 48 mN / m to obtain a film (B) which is a raw material for a polyolefin resin composition. -1 / 2020cm -1The results of the ratio, integrated chemiluminescence intensity, and static friction coefficient are shown in Table 1. <Conditions for corona treatment> Distance between electrode and film surface: 1.5 mm Roll speed: 30m / min Processing power: 230W Processing count: 1 time

[0128] Example 4 A film (A) was obtained in the same manner as in Example 1, except that a corona treatment was performed on both sides of the untreated film so that the wet tension was 48 mN / m each to obtain a film (B) that is a raw material for a polyolefin resin composition. -1 / 2020cm -1 The results of the ratio, integrated chemiluminescence intensity, and static friction coefficient are shown in Table 1.

[0129] (Comparative Example 1) A film (A) was obtained in the same manner as in Example 1, except that the untreated film was used as the film (B) which is the raw material for the polyolefin resin composition. -1 / 2020cm -1 The results of the ratio, integrated chemiluminescence intensity, and static friction coefficient are shown in Table 1.

[0130] (Comparative Example 2) A film (A) was obtained in the same manner as in Comparative Example 1, except that the temperature setting of the Labo Plastomill was 210°C. -1 / 2020cm -1 The results of the ratio, integrated chemiluminescence intensity, and static friction coefficient are shown in Table 1.

[0131] (Comparative Example 3) A film (A) was obtained in the same manner as in Comparative Example 2, except that the residence time was 20 minutes. -1 / 2020cm -1The results of the ratio, integrated chemiluminescence intensity, and static friction coefficient are shown in Table 1.

[0132] [Table 1]

[0133] Comparative Example 4 [Production of unprocessed film] Low-density polyethylene (Sumikathen® F102-0 (Sumitomo Chemical Co., Ltd., production method: high-pressure radical polymerization, ethylene-derived monomer units: 100 mol%, density: 922 kg / m 3 , MFR: 0.35 g / 10 min) was fed to an inflation molding machine to produce an untreated film having a thickness of 100 μm.

[0134] One side of the untreated film was subjected to corona treatment using a corona treatment machine (manufactured by Softal Corporation, Japan) under the following conditions so that the wet tension was 41 mN / m. <Conditions for corona treatment> Distance between electrode and film surface: 1.5 mm Roll speed: 30m / min Processing power: 230W Processing count: 1 time

[0135] The obtained film was analyzed at 2330 cm -1 / 2020cm -1 The ratio was measured to be 0.91.

[0136] From Table 1, it was found that the films of the examples which satisfied all the constituent requirements of the present invention had a higher static friction coefficient than the films of Comparative Examples 1 to 3. This shows that the polyolefin resin composition according to the present invention can produce a film which is less slippery when wound up.

[0137] Furthermore, as can be seen from Examples 1 to 4 and Comparative Example 1, the polyolefin resin composition obtained by melt-kneading the corona-treated film (B) can be made to have a wet tension of 2330 cm 2 by adjusting the range of the wet tension of at least one surface of the polyolefin resin composition, which is obtained by molding the polyolefin resin composition. -1 / 2020cm -1 On the other hand, when only one side of an untreated film is subjected to a corona treatment as in Comparative Example 4, the functional groups are formed only on the surface and are not dispersed to the interior, and the functional groups are not subjected to heat. -1 / 2020cm -1 The ratio never exceeded 1.24.

[0138] Furthermore, as can be seen from the results of Comparative Example 3, even if the film is simply degraded under more severe melt-kneading conditions than those of the examples, the film does not reach the 2330 cm specified in the present invention. -1 / 2020cm -1 The ratio range was not satisfied, and the film (A) obtained in Comparative Example 3 had a low static friction coefficient and was slippery.

Claims

1. A polyolefin-based resin composition containing a polyolefin-based resin in an amount of 80 mass% or more based on the polyolefin-based resin composition, and satisfying the following (1): (1) In the infrared absorption spectrum of the film (A) obtained by molding the polyolefin resin composition, －１ The absorbance at the peak top appearing near 2330 cm －１ The absorbance ratio at the peak top appearing in the vicinity is 1.24 or more.

2. The polyolefin resin composition according to claim 1, further satisfying the following (2): (2) The integrated chemiluminescence intensity of the film (A) obtained by dividing the integrated value of the chemiluminescence intensity from the start of measurement at a wavelength of 300 nm or more to 850 nm or less until 300 seconds by the mass of the film (A) is 1.5 × 10 ５ count / g or more 3.0×10 ６ counts / g or less.

3. The polyolefin resin composition according to claim 1, wherein the content of the polyolefin resin is 90% by mass or more based on the polyolefin resin composition.

4. 2. The polyolefin resin composition according to claim 1, wherein the polyolefin resin is at least one of a polyethylene resin and a polypropylene resin.

5. The raw material of the polyolefin resin composition includes a film (B) containing a polyolefin resin, 2. The polyolefin resin composition according to claim 1, wherein the film (B) has been subjected to at least one treatment selected from the group consisting of a corona treatment, a plasma treatment, and an ozone treatment.

6. The polyolefin resin composition according to claim 5, further satisfying the following (3): (3) The wet tension of at least one of the surfaces of the film (B) is 32 mN / m or more and 60 mN / m or less.

7. The polyolefin resin composition according to claim 6, wherein the film (B) is at least one of a resin film collected from the market and a resin film collected from within a process.

8. A method for producing the polyolefin resin composition according to any one of claims 1 to 7, The method includes a step of melt-kneading raw materials of the polyolefin resin composition for a residence time of 1 minute or more and 6 minutes or less, a raw material for the polyolefin resin composition comprising a film that has been subjected to at least one treatment selected from the group consisting of a corona treatment, a plasma treatment, and an ozone treatment, and at least one of the surfaces of the film has a wet tension of 32 mN / m or more and 60 mN / m or less.

9. A film comprising the polyolefin resin composition according to any one of claims 1 to 7.

10. A packaging bag comprising the film of claim 9.

11. Contains a polyolefin-based resin composition, In the infrared absorption spectrum, 2020 cm －１ The absorbance at the peak top appearing near 2330 cm －１ A film having an absorbance ratio of 1.24 or more at the peak tops appearing near the

12. 10. The film of claim 9, which is a stretched or unstretched film.

13. 12. The film of claim 11, which is a stretched or unstretched film.

14. 13. The film of claim 12, wherein the stretched film is a uniaxially stretched film or a biaxially stretched film.

15. 14. The film of claim 13, wherein the stretched film is a uniaxially stretched film or a biaxially stretched film.

16. The film according to claim 9, obtained by molding the polyolefin resin composition under press conditions of a temperature of 230°C and a pressure of 10 MPa.

17. The film according to claim 11, obtained by molding a polyolefin resin composition under press conditions of a temperature of 230°C and a pressure of 10 MPa.

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