Resin films, laminates and packaging products

Abstract

To provide a resin film which is excellent in opening property of a packaging product while reducing discharge of carbon dioxide by reducing a used amount of a fossil foil.SOLUTION: A resin film includes at least a first layer and a second layer. In the resin film, the second layer constitutes at least one outermost layer of the resin film. The first layer and the second layer are layered directly or through a thermoplastic resin layer. The resin film contains linear low density polyethylene and low density polyethylene. The resin film contains biomass-derived polyethylene. The resin film has an area ratio of a region having a molecular weight of 30,000 or less in molecular weight distribution curve obtained from measurement of GPC of the first layer of 12.0% or less with respect to the total peak area according to JIS K 7252-1:2008.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a resin film and a laminate including the same. The present invention also relates to a packaging product including the laminate. [Background technology]

[0002] In recent years, with growing calls for the creation of a recycling-oriented society, there has been a desire to move away from fossil fuels in the materials field, just as there has been in energy, and the use of biomass has been attracting attention. Biomass is an organic compound formed by photosynthesis from carbon dioxide and water, and by using it, it can be converted back into carbon dioxide and water, making it a so-called carbon-neutral renewable energy source. Recently, the practical application of biomass plastics made from these biomass materials has progressed rapidly, and attempts are also being made to produce various resins from biomass materials.

[0003] Among biomass-derived resins, polylactic acid (PLA), which is produced via lactic acid fermentation, was the first to be commercially produced, but because its performance as a plastic, including its biodegradability, is significantly different from that of current general-purpose plastics, there are limitations to its product applications and manufacturing methods, and it has not yet become widely used.In addition, a life cycle assessment (LCA) is being conducted on PLA, and discussions are underway regarding the energy consumption during PLA production and its equivalence as a replacement for general-purpose plastics.

[0004] Various types of general-purpose plastics are used, including polyethylene, polypropylene, polyvinyl chloride, polystyrene, and polyester. Polyethylene, in particular, is molded into films, sheets, bottles, and the like and is used in a variety of applications, such as packaging, and is used in large quantities worldwide. Therefore, using conventional fossil fuel-derived polyethylene places a heavy burden on the environment. Therefore, it is desirable to reduce the amount of fossil fuel used by using biomass-derived raw materials in the production of polyethylene. For example, research has been conducted to date on the production of ethylene and butylene, the raw materials for polyolefin resins, from renewable natural raw materials (see Patent Document 1).

[0005] For example, Patent Document 2 discloses a resin film made of a resin composition containing a carbon-neutral polyolefin, which contains a biomass-derived polyolefin obtained by polymerizing a monomer containing ethylene derived from biomass, and has a carbon density of 0.91 to 0.96 g / cm. 3 (910kg / m 3 ~960kg / m 3 The document also discloses a resin film made of a resin composition characterized by having a density of 1000 MPa (1000 MPa) or less. The document also describes that the resin film is comparable in mechanical properties to resin films produced from conventional raw materials obtained from fossil fuels. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Special Publication No. 2011-506628 [Patent Document 2] Special Publication No. 2012-251006 Summary of the Invention [Problem to be solved by the invention]

[0007] In the manufacturing process of a packaged product such as a packaging bag, the inner surfaces of a laminate are heat-sealed so that a portion of the outer edge of the packaged product remains as an opening. Next, the contents are filled into the bag through the opening. After that, the opening is sealed by heat sealing. In this way, a packaged product containing the contents can be obtained. In this case, to increase the productivity of the packaged product, it is necessary that the contents can be easily filled. Therefore, it is important that the opening can be easily opened (openability) after the inner surfaces of the laminate are heat-sealed. The resin film disclosed in Patent Document 2 is also used as a sealant layer on the inner surface of such a packaged product, but there is room for improvement in the openability of the packaged product.

[0008] The present inventors have found that the above problem can be solved by reducing the content of low molecular weight components in the resin film to a certain amount or less.

[0009] Therefore, an object of the present invention is to provide a resin film that is excellent in opening properties for packaging products while reducing the amount of fossil fuel used and thereby reducing carbon dioxide emissions. [Means for solving the problem]

[0010] The present invention provides a resin film comprising at least a first layer and a second layer, wherein the first layer constitutes at least one outermost layer of the resin film, the first layer and the second layer are laminated together directly or via a thermoplastic resin layer, the resin film contains linear low-density polyethylene and low-density polyethylene, and the resin film contains biomass-derived polyethylene, and the area proportion of a region having a molecular weight of 30,000 or less in a molecular weight distribution curve obtained by GPC measurement of the first layer in accordance with JIS K 7252-1:2008 is 12.0% or less of the total peak area.

[0011] In the resin film according to the present invention, the second layer may contain biomass-derived polyethylene.

[0012] In the resin film according to the present invention, the second layer may contain low-density polyethylene.

[0013] In the resin film according to the present invention, the second layer may contain biomass-derived low-density polyethylene.

[0014] In the resin film according to the present invention, the first layer may contain linear low-density polyethylene.

[0015] In the resin film according to the present invention, the first layer may contain polyethylene derived from fossil fuels.

[0016] In the resin film according to the present invention, the first layer may have a dispersity of 5.0 or less.

[0017] In the resin film according to the present invention, the biomass content may be 5% or more.

[0018] In the resin film according to the present invention, the resin film further comprises a third layer, the third layer constituting the other outermost layer of the resin film, and the second layer and the third layer may be laminated directly or via a thermoplastic resin layer.

[0019] In the resin film according to the present invention, the third layer may contain linear low-density polyethylene.

[0020] The present invention is a laminate comprising the resin film and a substrate layer.

[0021] The present invention is a packaging product comprising the laminate.

[0022] In the packaging product according to the present invention, the first layer may be located on the innermost surface of the packaging product. [Effects of the Invention]

[0023] According to the present invention, it is possible to provide a resin film that has excellent opening properties for packaging products while reducing carbon dioxide emissions by reducing the amount of fossil fuel used. Packaging products using such a resin film have excellent suitability for filling contents. [Brief explanation of the drawings]

[0024] [Figure 1] 1 is a cross-sectional view showing an example of a resin film of the present invention. [Figure 2] 1 is a cross-sectional view showing an example of a resin film of the present invention. [Figure 3] 1 is a cross-sectional view showing an example of a resin film of the present invention. [Figure 4] 1 is a cross-sectional view showing an example of a resin film of the present invention. [Figure 5] 1 is a cross-sectional view showing an example of a resin film of the present invention. [Figure 6] 1 is a cross-sectional view showing an example of a resin film of the present invention. [Figure 7] 1 is a cross-sectional view showing an example of a laminate of the present invention. [Figure 8] FIG. 1 is a diagram showing an example of a packaging container provided with the laminate of the present invention. [Figure 9] FIG. 1 shows the layer structures of the resin films of Examples 1 to 15 and Comparative Examples 1 to 3, as well as the results of GPC measurement and openability. DETAILED DESCRIPTION OF THE INVENTION

[0025] (resin film) Fig. 1 is a cross-sectional view showing an example of a resin film 10 of the present invention. The resin film 10 includes a first layer 11 and a second layer 12. The first layer 11 constitutes one of the outermost layers of the resin film 10. The first layer 11 and the second layer 12 are directly laminated together.

[0026] 2 is a cross-sectional view showing another example of the resin film 10 of the present invention. The resin film 10 is provided with a first layer 11, a thermoplastic resin layer 13, and a second layer 12, in that order. The first layer 11 constitutes one of the outermost layers of the resin film 10. The first layer 11 and the second layer 12 are laminated with the thermoplastic resin layer 13 interposed therebetween.

[0027] 3 is a cross-sectional view showing another example of the resin film 10 of the present invention. The resin film 10 is provided with a first layer 11, a second layer 12, and a third layer 14, in that order. The first layer 11 constitutes one of the outermost layers of the resin film 10. The third layer 14 constitutes the other outermost layer of the resin film 10. The first layer 11 and the second layer 12 are directly laminated together. The second layer 12 and the third layer 14 are directly laminated together.

[0028] 4 is a cross-sectional view showing another example of the resin film 10 of the present invention. The resin film 10 is provided with a first layer 11, a second layer 12, a thermoplastic resin layer 13, and a third layer 14, in that order. The first layer 11 constitutes one of the outermost layers of the resin film 10. The third layer 14 constitutes the other outermost layer of the resin film 10. The first layer 11 and the second layer 12 are laminated directly together. The second layer 12 and the third layer 14 are laminated together with the thermoplastic resin layer 13 interposed therebetween.

[0029] FIG. 5 is a cross-sectional view showing another example of the resin film 10 of the present invention. The resin film 10 comprises, in order, a first layer 11, a thermoplastic resin layer 13, a second layer 12, and a third layer 14. The first layer 11 constitutes one of the outermost layers of the resin film 10. The third layer 14 constitutes the other outermost layer of the resin film 10. The first layer 11 and the second layer 12 are laminated with the thermoplastic resin layer 13 interposed therebetween. The second layer 12 and the third layer 14 are directly laminated.

[0030] 6 is a cross-sectional view showing another example of the resin film 10 of the present invention. The resin film 10 is provided with a first layer 11, a thermoplastic resin layer 13, a second layer 12, a thermoplastic resin layer 15, and a third layer 14, in that order. The first layer 11 constitutes one of the outermost layers of the resin film 10. The third layer 14 constitutes the other outermost layer of the resin film 10. The first layer 11 and the second layer 12 are laminated with the thermoplastic resin layer 13 interposed therebetween. The second layer 12 and the third layer 14 are laminated with the thermoplastic resin layer 15 interposed therebetween.

[0031] It is also possible to appropriately combine a plurality of layer structures of the resin film 10 shown in the above-mentioned FIGS.

[0032] The resin film contains linear low-density polyethylene and low-density polyethylene. By containing linear low-density polyethylene, the seal strength and impact resistance such as drop strength of the resin film can be improved. By containing low-density polyethylene, the tearability of the resin film can be improved.

[0033] Here, we will explain low-density polyethylene (LDPE) and linear low-density polyethylene (LLDEP). Low-density polyethylene is a high-pressure ethylene homopolymer, which can be obtained by a conventionally known high-pressure radical polymerization method. Linear low-density polyethylene is a copolymer of ethylene and an α-olefin polymerized using a multi-site catalyst, such as a Ziegler-Natta catalyst, or a single-site catalyst, such as a metallocene catalyst. Both have a density of 930 kg / m 3 The α-olefin used as a comonomer for linear low-density polyethylene includes α-olefins having 3 to 20 carbon atoms, such as propylene, 1-butene, 1-pentene, 1-hexene, 1-octene, 1-nonene, 4-methylpentene, and mixtures thereof. Here, the density of polyethylene is a value measured according to the method specified in Method A of JIS K7112-1980 after annealing as specified in JIS K6760-1995.

[0034] The single-site catalyst is a catalyst capable of forming a uniform active species, and is usually prepared by contacting a metallocene transition metal compound or a non-metallocene transition metal compound with an activating co-catalyst. Single-site catalysts are preferred because they have a more uniform active site structure than multi-site catalysts, making it possible to polymerize polymers with high molecular weights and highly uniform structures. Metallocene catalysts are particularly preferred as single-site catalysts. Metallocene catalysts are catalysts containing the following catalytic components: a transition metal compound of Group IV of the periodic table containing a ligand with a cyclopentadienyl skeleton, a co-catalyst, and optionally an organometallic compound and a carrier.

[0035] In the above-mentioned transition metal compound of Group IV of the periodic table containing a ligand having a cyclopentadienyl skeleton, the cyclopentadienyl skeleton is a cyclopentadienyl group, a substituted cyclopentadienyl group, or the like. The substituted cyclopentadienyl group has at least one substituent selected from a hydrocarbon group having 1 to 30 carbon atoms, a silyl group, a silyl-substituted alkyl group, a silyl-substituted aryl group, a cyano group, a cyanoalkyl group, a cyanoaryl group, a halogen group, a haloalkyl group, a halosilyl group, and the like. The substituted cyclopentadienyl group may have two or more substituents, and the substituents may be bonded to each other to form a ring, such as an indenyl ring, a fluorenyl ring, an azulenyl ring, or a hydrogenated product thereof. The rings formed by bonding the substituents to each other may further have substituents.

[0036] In a transition metal compound of Group IV of the periodic table containing a ligand having a cyclopentadienyl skeleton, the transition metal may be zirconium, titanium, hafnium, or the like, with zirconium and hafnium being particularly preferred. The transition metal compound typically contains two ligands having a cyclopentadienyl skeleton, and the ligands having the cyclopentadienyl skeleton are preferably bonded to each other via a bridging group. Examples of the bridging group include alkylene groups having 1 to 4 carbon atoms, silylene groups, substituted silylene groups such as dialkylsilylene groups and diarylsilylene groups, and substituted germylene groups such as dialkylgermylene groups and diarylgermylene groups. A substituted silylene group is preferred.

[0037] In the transition metal compounds of Group IV of the periodic table, representative examples of the ligand other than the ligand having a cyclopentadienyl skeleton include hydrogen, hydrocarbon groups having 1 to 20 carbon atoms (such as alkyl groups, alkenyl groups, aryl groups, alkylaryl groups, aralkyl groups, and polyenyl groups), halogens, metaalkyl groups, and metaaryl groups.

[0038] The above-mentioned compounds of transition metals of Group IV of the periodic table containing a ligand having a cyclopentadienyl skeleton can be used as a catalyst component either singly or in combination of two or more kinds.

[0039] The co-catalyst refers to a catalyst that can effectively use the above-mentioned transition metal compound of Group IV of the periodic table as a polymerization catalyst or that can balance the ionic charge in a catalytically activated state. Examples of the co-catalyst include benzene-soluble aluminoxanes of organoaluminum oxy compounds and benzene-insoluble organoaluminum oxy compounds, ion-exchangeable layered silicates, boron compounds, ionic compounds consisting of a cation with or without an active hydrogen group and a non-coordinating anion, lanthanoid salts such as lanthanum oxide, tin oxide, and phenoxy compounds containing a fluoro group.

[0040] The transition metal compound of Group IV of the periodic table containing a ligand having a cyclopentadienyl skeleton may be used by being supported on an inorganic or organic support, preferably an inorganic or organic porous oxide, such as montmorillonite or other ion-exchangeable layered silicates, SiO2, Al2O3, MgO, ZrO2, TiO2, BO3, CaO, ZnO, BaO, ThO2, or mixtures thereof.

[0041] Furthermore, examples of organometallic compounds that may be used if necessary include organoaluminum compounds, organomagnesium compounds, organozinc compounds, etc. Of these, organoaluminum compounds are preferably used.

[0042] The low-density polyethylene and linear low-density polyethylene preferably have a melt flow rate (MFR) of 0.1 g / 10 min to 10 g / 10 min, more preferably 0.2 g / 10 min to 9 g / 10 min, and even more preferably 1 g / 10 min to 8.5 g / 10 min. The melt flow rate is a value measured by Method A under conditions of a temperature of 190°C and a load of 21.18 N in accordance with the method specified in JIS K7210-1995. If the MFR is 0.1 g / 10 min or more, the extrusion load during molding can be reduced. Furthermore, if the MFR is 10 g / 10 min or less, the mechanical strength of the resin film can be increased.

[0043] The resin film may contain high density polyethylene (HDPE) or medium density polyethylene (MDPE) within the scope of the present invention. 3 More than 942kg / m 3 High density polyethylene refers to polyethylene having a density of less than 942 kg / m 3 This refers to polyethylene having a density of 100% or more.

[0044] The resin film contains polyethylene derived from biomass. The resin film preferably has a biomass ratio, as described below, of 5% or more, more preferably 10% to 95%, and even more preferably 10% to 80%. If the biomass ratio is within the above range, the amount of fossil fuel used can be reduced, and the environmental load can be reduced. Unless otherwise specified, the "biomass ratio" refers to the weight ratio of biomass-derived components.

[0045] <Biomass-derived ethylene> The method for producing biomass-derived ethylene, which is a raw material for biomass-derived polyethylene (hereinafter also referred to as biomass polyethylene), is not particularly limited, and it can be obtained by a conventionally known method. An example of a method for producing biomass-derived ethylene will be described below.

[0046] Biomass-derived ethylene can be produced using biomass-derived ethanol as a raw material. In particular, it is preferable to use biomass-derived fermented ethanol obtained from plant raw materials. The plant raw material is not particularly limited, and conventionally known plants can be used. Examples include corn, sugarcane, beet, and manioc.

[0047] Fermented ethanol derived from biomass refers to ethanol produced by contacting a culture solution containing a carbon source obtained from plant raw materials with an ethanol-producing microorganism or a product derived from the disrupted microorganism, followed by purification. Ethanol can be purified from the culture solution by conventional methods such as distillation, membrane separation, and extraction. Examples of such methods include adding benzene, cyclohexane, or the like and removing water by azeotropy or membrane separation.

[0048] In order to obtain the above ethylene, further advanced purification may be carried out at this stage, for example, to reduce the total amount of impurities in the ethanol to 1 ppm or less.

[0049] A catalyst is usually used when obtaining ethylene by the dehydration reaction of ethanol, but the catalyst is not particularly limited and any conventionally known catalyst can be used. From the viewpoint of the process, a fixed-bed flow reaction is advantageous because it allows easy separation of the catalyst and the product, and for example, γ-alumina is preferred.

[0050] Since this dehydration reaction is an endothermic reaction, it is usually carried out under heating conditions. The heating temperature is not limited as long as the reaction proceeds at a commercially useful reaction rate, but is preferably 100°C or higher, more preferably 250°C or higher, and even more preferably 300°C or higher. There is no particular upper limit, but from the viewpoint of energy balance and equipment, it is preferably 500°C or lower, more preferably 400°C or lower.

[0051] In the dehydration reaction of ethanol, the yield of the reaction depends on the amount of water contained in the ethanol supplied as a raw material. Generally, when performing a dehydration reaction, it is preferable to eliminate water in consideration of the efficiency of water removal. However, in the case of the dehydration reaction of ethanol using a solid catalyst, it has been found that the absence of water tends to increase the amount of other olefins, particularly butene, produced. This is presumably because the presence of a small amount of water is insufficient to suppress ethylene dimerization after dehydration. The lower limit of the allowable water content is 0.1% by mass or more, preferably 0.5% by mass or more. There are no particular limitations on the upper limit, but from the viewpoints of material balance and heat balance, it is preferably 50% by mass or less, more preferably 30% by mass or less, and even more preferably 20% by mass or less.

[0052] By carrying out the dehydration reaction of ethanol in this manner, a mixture of ethylene, water, and a small amount of unreacted ethanol is obtained, but since ethylene is in a gaseous state at room temperature and below about 5 MPa, water and ethanol can be removed from this mixture by gas-liquid separation to obtain ethylene. This method can be carried out by any known method.

[0053] The ethylene obtained by the gas-liquid separation is further distilled. The distillation method, operation temperature, residence time, etc. are not particularly limited, except that the operation pressure at this time must be atmospheric pressure or higher.

[0054] When biomass-derived ethanol is used as the raw material, the resulting ethylene contains trace amounts of impurities introduced during the ethanol fermentation process, such as carbonyl compounds (e.g., ketones, aldehydes, and esters) and their decomposition products (e.g., carbon dioxide), as well as nitrogen-containing compounds (e.g., amines and amino acids) and their decomposition products (e.g., ammonia), which are enzymatic decomposition products and contaminants. Depending on the intended use of ethylene, these trace amounts of impurities may be problematic, so they may be removed by purification. The purification method is not particularly limited, and conventionally known methods can be used. An example of a suitable purification procedure is adsorption purification. The adsorbent used is not particularly limited, and conventionally known adsorbents can be used. For example, a material with a high surface area is preferred, and the type of adsorbent is selected depending on the type and amount of impurities in the ethylene obtained by the dehydration reaction of biomass-derived ethanol.

[0055] A caustic water treatment may be used in combination as a method for purifying impurities in ethylene. When caustic water treatment is used, it is preferable to carry out the treatment before adsorption purification. In this case, it is necessary to carry out a water removal treatment after the caustic treatment and before adsorption purification.

[0056] <Biomass polyethylene> Biomass polyethylene is obtained by polymerizing a monomer containing biomass-derived ethylene. It is preferable to use biomass-derived ethylene obtained by the above-mentioned production method. Since biomass-derived ethylene is used as the raw material monomer, the polymerized polyethylene is biomass-derived. When the biomass polyethylene is biomass-derived low-density polyethylene, it is polyethylene polymerized by the above-mentioned polymerization method using biomass-derived ethylene. Note that the raw material monomer for polyethylene does not have to contain 100% by mass of biomass-derived ethylene.

[0057] As long as the object of the present invention is not impaired, the monomers that are raw materials for biomass polyethylene may further contain ethylene derived from fossil fuels.

[0058] The biomass-derived ethylene concentration in the polyethylene (hereinafter sometimes referred to as "biomass content") is a value measured by radiocarbon (C14) analysis to determine the amount of biomass-derived carbon. Atmospheric carbon dioxide contains a certain percentage of C14 (105.5 pMC), and it is known that the C14 content in plants that grow by absorbing atmospheric carbon dioxide, such as corn, is also about 105.5 pMC. It is also known that fossil fuels contain very little C14. Therefore, by measuring the percentage of C14 in the total carbon atoms in the polyethylene, the percentage of biomass-derived carbon can be calculated, and the weight ratio of biomass-derived components can be determined.

[0059] In the present invention, theoretically, if all biomass-derived ethylene is used as a raw material for polyethylene, the concentration of biomass-derived ethylene will be 100%, and the biomass content of biomass polyethylene will be 100%. Also, the concentration of biomass-derived ethylene in fossil fuel-derived polyethylene produced only from fossil fuel-derived raw materials will be 0%, and the biomass content of fossil fuel-derived polyethylene will be 0%.

[0060] In the present invention, the biomass polyethylene or biomass-derived resin layer does not need to have a biomass content of 100%. This is because the use of biomass-derived raw materials in even a part of the resin film is in line with the purpose of the present invention, which is to reduce the amount of fossil fuel used compared to conventional methods.

[0061] The thickness of the resin film is preferably 15 to 250 μm, more preferably 20 to 200 μm, and even more preferably 30 to 150 μm.

[0062] The density of the resin film is 901 kg / m 3 More than 930kg / m 3 Preferably less than 905 kg / m 3 More than 925kg / m 3 It is more preferable that the density of the resin film is less than 901 g / cm 3If the density of the resin film is 930 g / cm or more, the rigidity of the resin film can be increased. 3 If it is less than this, the mechanical strength of the resin film can be increased.

[0063] The resin film comprises at least a first layer and a second layer. The first layer and the second layer are laminated together directly or via a thermoplastic resin layer. The resin film may further comprise a third layer. The second layer and the third layer may be laminated together directly or via a thermoplastic resin layer. Each layer constituting the resin film will be described below.

[0064] (1st layer) The first layer constitutes at least one outermost layer of the resin film, which can improve the ease of opening the packaged product.

[0065] The first layer is subjected to GPC (gel permeation chromatography) measurement in accordance with JIS K 7252-1:2008 (Plastics - Determination of average molecular weight of polymers by size exclusion chromatography). The area ratio of the region of molecular weight of 30,000 or less in the molecular weight distribution curve obtained from the measurement is 12.0% or less of the total peak area (distribution area). Components with a molecular weight of 30,000 or less (hereinafter also referred to as low molecular weight components) contained in the first layer are adhesive, and the low molecular weight components in the first layer reduce the openability of packaged products during the manufacturing process of the packaged products. By setting the area ratio of the region of molecular weight of 30,000 or less in the first layer to 12.0% or less of the total peak area, i.e., by setting the content of low molecular weight components in the first layer to 12.0% or less by mass, it is possible to suppress adhesion due to the low molecular weight components and improve the openability of packaged products. The area proportion of the region of molecular weight of 30,000 or less in the first layer is preferably 10.5% or less of the total peak area, more preferably 10.0% or less, from the viewpoint of further improving the opening property of the packaged product.

[0066] The GPC measurement of the first layer can be performed by any other common method as long as it complies with JIS K 7252-1:2008. However, it is preferable to use an HLC (registered trademark)-8321 GPC / HT type high temperature gel permeation chromatograph (manufactured by Tosoh Corporation) as the gel permeation chromatograph, two TSKgel GMH6-HT (ID 7.5 mm × 300 mm) columns and two TSKgel GMH6-HTL (ID 7.5 × 300 mm) columns (manufactured by Tosoh Corporation) as the columns, and o-dichlorobenzene (containing 0.025% by mass of dibutylhydroxytoluene (BHT)) as the mobile phase, at a column temperature of 140°C.

[0067] The dispersity of the first layer (weight average molecular weight Mw / number average molecular weight Mn) is preferably 5.0 or less, more preferably 4.5 or less, and even more preferably 4.0 or less, which can further improve the opening ease of the packaged product.

[0068] The first layer may contain linear low-density polyethylene, which can further improve the openability of the packaged product and the impact resistance, such as the seal strength and drop strength, of the resin film. The linear low-density polyethylene may be biomass-derived linear low-density polyethylene, fossil fuel-derived linear low-density polyethylene, or both biomass-derived linear low-density polyethylene and fossil fuel-derived linear low-density polyethylene.

[0069] The content of linear low-density polyethylene in the first layer is preferably 30% by mass or more, more preferably 50% by mass or more, and even more preferably 70% by mass or more, which can further improve the openability of the packaged product and the seal strength and impact resistance such as drop strength of the resin film.

[0070] The first layer may contain fossil fuel-derived polyethylene, which can further improve the openability of the packaged product. The content of fossil fuel-derived polyethylene in the first layer is preferably 30% by mass or more, more preferably 50% by mass or more, and even more preferably 70% by mass or more. This can further improve the openability of the packaged product.

[0071] The first layer may contain biomass-derived polyethylene. This allows for further reduction in the amount of fossil fuel used. The content of biomass-derived polyethylene in the first layer is preferably 1% by mass to 70% by mass, more preferably 5% by mass to 50% by mass, and even more preferably 10% by mass to 30% by mass. This allows for further reduction in the amount of fossil fuel used while improving the ease of opening the packaged product.

[0072] The biomass content of the first layer is preferably 1% to 70%, more preferably 5% to 50%, and even more preferably 10% to 30%, which can improve the opening properties of the packaged product while further reducing the amount of fossil fuel used.

[0073] The first layer may contain high density polyethylene (HDPE) or medium density polyethylene (MDPE) within the scope of the present invention.

[0074] The thickness of the first layer is preferably 5 to 100 μm, more preferably 5 to 80 μm, and even more preferably 10 to 50 μm.

[0075] The ratio of the thickness of the first layer to the second layer is preferably 1:5 to 2:1, and more preferably 1:4 to 1:1.

[0076] (2nd layer) The second layer may contain biomass-derived polyethylene, which allows for further reduction in the amount of fossil fuel used. The content of biomass-derived polyethylene in the second layer is preferably 30% by mass or more, more preferably 50% by mass or more, and even more preferably 70% by mass or more, which allows for further reduction in the amount of fossil fuel used.

[0077] The biomass ratio of the second layer is preferably 30% or more, more preferably 50% or more, and even more preferably 70% or more, which allows for further reduction in the amount of fossil fuel used.

[0078] The second layer may contain low-density polyethylene, which can improve the tearability of the resin film. The second layer may also contain biomass-derived low-density polyethylene, which can improve the tearability of the resin film while further reducing the amount of fossil fuel used. The second layer may also contain fossil-fuel-derived low-density polyethylene.

[0079] The content of low-density polyethylene in the second layer is preferably 30% by mass or more, more preferably 50% by mass or more, and even more preferably 70% by mass or more, which can further improve the tearability of the resin film.

[0080] The second layer may contain linear low-density polyethylene, which can improve the seal strength and impact resistance, such as drop strength, of the resin film. The linear low-density polyethylene may be biomass-derived linear low-density polyethylene, linear fossil fuel-derived low-density polyethylene, or both biomass-derived linear low-density polyethylene and fossil fuel-derived linear low-density polyethylene.

[0081] The second layer may contain high density polyethylene (HDPE) or medium density polyethylene (MDPE) within the scope of the present invention.

[0082] The thickness of the second layer is preferably 10 to 150 μm, more preferably 15 to 120 μm, and even more preferably 20 to 100 μm.

[0083] (3rd layer) The third layer constitutes the other outermost layer of the resin film, which can improve adhesion to other layers when a laminate is formed.

[0084] The third layer may contain linear low-density polyethylene. This improves adhesion to other layers while improving the seal strength and impact resistance, such as drop strength, of the resin film. The third layer may also contain biomass-derived linear low-density polyethylene. This allows for further reductions in the amount of fossil fuel used. The third layer may also contain fossil-derived linear low-density polyethylene.

[0085] The content of linear low-density polyethylene in the third layer is preferably 30% by mass or more, more preferably 50% by mass or more, and even more preferably 70% by mass or more, which can improve the adhesion to other layers and further improve the seal strength and impact resistance such as drop strength of the resin film.

[0086] The third layer may contain low-density polyethylene, which can improve the tearability of the resin film. The third layer may also contain biomass-derived low-density polyethylene, which can further reduce the amount of fossil fuel used. The third layer may also contain fossil-derived low-density polyethylene.

[0087] The content of linear low-density polyethylene in the third layer is preferably from 1 to 70% by mass, more preferably from 1 to 50% by mass, and even more preferably from 1 to 30% by mass, which can improve the tearability of the resin film and further improve adhesion to other layers.

[0088] The biomass ratio in the third layer is preferably 5% or more, and more preferably 10% to 95%, which allows for further reduction in the amount of fossil fuel used.

[0089] The thickness of the third layer is preferably 5 to 100 μm, more preferably 5 to 80 μm, and even more preferably 10 to 50 μm.

[0090] The thickness ratio of the second layer:the third layer is preferably 5:2 to 1:2, and more preferably 4:1 to 1:1.

[0091] (thermoplastic resin layer) The thermoplastic resin layer is a layer formed to bond any two layers together by lamination. The thermoplastic resin layer can be formed by a conventionally known method, for example, a melt extrusion lamination method or a sand lamination method. The thermoplastic resin layer can be made of a polyolefin resin such as a polyethylene resin or a polypropylene resin, a cyclic polyolefin resin, or a copolymer resin, modified resin, or mixture (including alloy) containing these resins as the main component. Examples of polyolefin resins include low-density polyethylene (LDPE), medium-density polyethylene (MDPE), high-density polyethylene (HDPE), linear low-density polyethylene (LLDPE), polypropylene (PP), ethylene-α-olefin copolymers polymerized using a metallocene catalyst, ethylene-polypropylene random or block copolymers, ethylene-vinyl acetate copolymer (EVA), ethylene-acrylic acid copolymer (EAA), ethylene-ethyl acrylate copolymer (EEA), ethylene-methacrylic acid copolymer (EMAA), ethylene-methyl methacrylate copolymer (EMMA), ethylene-maleic acid copolymer, and ionomer resins. To improve interlayer adhesion, acid-modified polyolefin resins obtained by modifying the above polyolefin resins with unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic acid, maleic anhydride, fumaric acid, and itaconic acid can also be used. Furthermore, resins obtained by graft-polymerizing or copolymerizing unsaturated carboxylic acids, unsaturated carboxylic anhydrides, or ester monomers with polyolefin resins can also be used. These materials can be used alone or in combination of two or more. Examples of cyclic polyolefin resins that can be used include cyclic polyolefins such as ethylene-propylene copolymers, polymethylpentene, polybutene, and polynorbornene. These resins can be used alone or in combination of two or more.

[0092] The thermoplastic resin layer may include a material derived from biomass or a material derived from fossil fuels.

[0093] (Method of manufacturing resin film) The method for producing the resin film of the present invention is not particularly limited, and the film can be produced by a conventionally known method. The resin film is preferably produced by coextrusion molding, and the coextrusion molding is more preferably carried out by a T-die method or an inflation method.

[0094] For example, a resin film can be formed by extrusion molding using the following method. After the resins constituting the first layer and the resins constituting the second layer are dried, they are fed into a melt extruder heated to a temperature above their melting points (Tm) to Tm+70°C, melted, and co-extruded into a sheet through a die such as a T-die. The co-extruded sheet is then quenched and solidified on a rotating cooling drum or the like to form a resin film. As the melt extruder, a single-screw extruder, twin-screw extruder, vent extruder, tandem extruder, or the like can be used depending on the purpose.

[0095] (Laminate) Fig. 7 is a cross-sectional view showing an example of a laminate 20 of the present invention. As shown in Fig. 7, the laminate 20 includes the resin film 10 and a base layer 21. By including the resin film in the laminate, the opening ease of the packaged product can be improved. Furthermore, the first layer of the resin film may constitute at least one outermost layer of the laminate.

[0096] (base material layer) The substrate layer includes at least one resin material, such as polyesters including polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyethylene naphthalate (PEN), 1,4-polycyclohexylene dimethylene terephthalate, and terephthalic acid-cyclohexanedimethanol-ethylene glycol copolymers; polyamides including nylon 6 and nylon 6,6; polyolefins including polyethylene (PE), polypropylene (PP), and polymethylpentene; vinyl resins including polyvinyl chloride, polyvinyl alcohol (PVA), polyvinyl acetate, vinyl chloride-vinyl acetate copolymers, polyvinyl butyral, and polyvinylpyrrolidone (PVP); (meth)acrylic resins including polyacrylate, polymethacrylate, and polymethyl methacrylate; cellulose resins including cellophane, cellulose acetate, nitrocellulose, cellulose acetate propionate (CAP), and cellulose acetate butyrate (CAB); styrene resins including polystyrene (PS), and chlorinated resins thereof. Among these, polyolefin, polyester and polyamide are preferred, and polypropylene, polyethylene terephthalate, nylon 6 and nylon 6,6 are more preferred. In the present invention, "(meth)acrylic" means to include both "acrylic" and "methacrylic", and "(meth)acrylate" means to include both "acrylate" and "methacrylate".

[0097] The base layer may contain additives such as fillers, plasticizers, antistatic agents, ultraviolet absorbers, inorganic particles, organic particles, release agents, and dispersants, as long as the properties of the present invention are not impaired.

[0098] The base layer may be a film containing the above-mentioned resin material, and the film may be a stretched film or an unstretched film, but from the viewpoint of strength, a stretched film that is stretched uniaxially or biaxially is preferred.

[0099] (Other layers) The laminate may have at least one other layer in addition to the above-mentioned layers. When the laminate has two or more other layers, the other layers may have the same composition or different compositions. The other layers can be formed on the substrate layer or the resin film. Examples of the other layers include a printed layer and an adhesive layer. The printed layer can be formed using a conventionally known pigment or dye, and the method for forming the printed layer is not particularly limited. The adhesive layer is an adhesive layer or adhesive resin layer formed to bond any two layers together by lamination.

[0100] The adhesive layer can be, for example, a one-component or two-component cured or non-cured vinyl-based, (meth)acrylic-based, polyamide-based, polyester-based, polyether-based, polyurethane-based, epoxy-based, rubber-based, or other solvent-based, water-based, or emulsion-based laminating adhesive. The adhesive can be applied by, for example, direct gravure roll coating, gravure roll coating, kiss coating, reverse roll coating, Fountain coating, transfer roll coating, or other methods. The amount of application is 0.1 g / m. 2 ~10g / m 2 (dry state) is preferable, 1g / m 2 ~5g / m 2 (dry state) is more preferable.

[0101] The adhesive resin layer may contain a thermoplastic resin. The adhesive resin layer can be formed by a conventionally known method, for example, a melt extrusion lamination method or a sand lamination method. The adhesive resin layer can be made of a polyolefin resin such as a polyethylene resin or a polypropylene resin, a cyclic polyolefin resin, or a copolymer resin, modified resin, or mixture (including alloy) containing these resins as the main component. Examples of polyolefin resins include low-density polyethylene (LDPE), medium-density polyethylene (MDPE), high-density polyethylene (HDPE), linear low-density polyethylene (LLDPE), polypropylene (PP), ethylene-α-olefin copolymers polymerized using a metallocene catalyst, ethylene-polypropylene random or block copolymers, ethylene-vinyl acetate copolymer (EVA), ethylene-acrylic acid copolymer (EAA), ethylene-ethyl acrylate copolymer (EEA), ethylene-methacrylic acid copolymer (EMAA), ethylene-methyl methacrylate copolymer (EMMA), ethylene-maleic acid copolymer, and ionomer resins. To improve interlayer adhesion, acid-modified polyolefin resins obtained by modifying the above polyolefin resins with unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic acid, maleic anhydride, fumaric acid, and itaconic acid can also be used. Furthermore, resins obtained by graft-polymerizing or copolymerizing unsaturated carboxylic acids, unsaturated carboxylic anhydrides, or ester monomers with polyolefin resins can also be used. These materials can be used alone or in combination of two or more. Examples of cyclic polyolefin resins that can be used include cyclic polyolefins such as ethylene-propylene copolymers, polymethylpentene, polybutene, and polynorbornene. These resins can be used alone or in combination of two or more.

[0102] The adhesive resin layer may contain a material derived from biomass or a material derived from fossil fuels.

[0103] (Method of manufacturing laminate) The method for producing the laminate is not particularly limited, and the laminate can be produced using a conventionally known method such as melt extrusion lamination, dry lamination, sand lamination, etc. For example, the laminate can be produced by extruding a resin film onto a substrate layer using the melt extrusion lamination method.

[0104] (packaged products) The packaged product includes the laminate. The packaged product may be one in which the first layer of the resin film is located on the innermost surface of the packaged product. The innermost surface is the surface of the packaged product that faces the contents to be contained in the packaged product.

[0105] The shape of the packaged product is not particularly limited, and may be a shape of a packaging bag 30 (stand-up pouch) as shown in Fig. 8. In the packaging bag 30, only the body 31 may be formed from the laminate, only the bottom 32 may be formed from the laminate, or both the body 31 and the bottom 32 may be formed from the laminate.

[0106] The packaging bag 30 can be produced by heat-sealing the laminate into a cylindrical shape with the resin film facing inside to form a body 31, and then folding another laminate into a V shape with the resin film facing inside the packaging bag 30, sandwiching it from one end of the body 31, and heat-sealing it to form a bottom 32. In Fig. 8, the hatched areas indicate the heat-sealed areas.

[0107] The heat sealing method is not particularly limited, and can be performed by known methods such as bar sealing, rotary roll sealing, belt sealing, impulse sealing, high frequency sealing, and ultrasonic sealing.

[0108] The contents filled into the packaged product are not particularly limited, and may be liquid, powder, or gel. The contents may be food or non-food. After the contents are filled, the opening is heat-sealed. [Example]

[0109] Next, the present invention will be explained in more detail with reference to examples. However, the present invention is not limited to the following examples as long as it does not depart from the gist of the present invention.

[0110] (GPC measurement conditions) Apparatus: HLC (registered trademark)-8321GPC / HT type high temperature gel permeation chromatograph (manufactured by Tosoh Corporation) Column: TSKgel GMH6-HT (ID 7.5 mm x 300 mm) x 2 + TSKgel GMH6-HTL (ID 7.5 x 300 mm) x 2 (Tosoh Corporation) Column temperature: 140℃ Mobile phase: o-dichlorobenzene (containing 0.025% by mass of dibutylhydroxytoluene (BHT)) ·Flow rate: 1.0mL / min. Sample concentration: 0.10% (W / V) ·Injection volume: 0.4mL Detector: Differential refractometer (RI) Column calibration: Standard polystyrene (monodisperse polystyrene, manufactured by Tosoh Corporation) Molecular weight calibration: Simple polystyrene equivalent

[0111] [Example 1] The resin constituting the first layer (Resin 1A) was 100 parts by mass of fossil fuel-derived linear low-density polyethylene (Petroleum LLDPE, manufactured by Prime Polymer Co., Ltd., product name: UZ2010L, density: 922 kg / m 3 , MFR: 2.2 g / 10 min, biomass content: 0%) was melted.

[0112] Next, as the resin (resin 2A) constituting the second layer, 100 parts by mass of biomass-derived low-density polyethylene (Bio-LDPE, manufactured by Braskem, trade name: SBC-818, density: 918 kg / m 3 , MFR: 8.1 g / 10 min, biomass content: 95%) was melted separately.

[0113] Next, 100 parts by mass of petrochemical LLDPE was separately melted as a resin (resin 3A) for forming the third layer.

[0114] These melts were co-extruded by inflation molding so that the first and third layers constituted the outermost layers of the resin film, producing a resin film with a layer thickness ratio of 1:2:1 (first layer: second layer: third layer). The thicknesses of the first and third layers were 32.5 μm, and the thickness of the second layer was 65.0 μm. The resin film had a thickness of 130.0 μm and a density of 920 kg / m 3 The biomass content of the resin film was 47.5%.

[0115] The first layer was peeled off from the obtained resin film, and 20 mg of the resin film was cut out. This was added to 20 mL of o-dichlorobenzene (containing 0.025% by mass of BHT) and boiled at 145°C to dissolve the resin film. This was hot-filtered through a sintered filter with a pore size of 1.0 μm to obtain a filtrate. This filtrate was measured under the above-mentioned GPC measurement conditions. In the obtained molecular weight distribution, the area ratio of the region with a molecular weight of 30,000 or less was 7.0%. The dispersity was 2.8.

[0116] Next, a laminate was produced containing the resin film of this example and a base material layer, with the first layer constituting the outermost layer. Using this laminate, a packaging bag with an opening was produced, with the first layer positioned on the innermost surface. The opening of the packaging bag was very easy to open. Such a packaging bag has excellent suitability for filling contents.

[0117] [Example 2] A resin film was prepared and GPC measurements were carried out in the same manner as in Example 1, except that two types of resins were used as the resins constituting the second layer. As the first resin (resin 2A) constituting the second layer, 50 parts by mass of bio-LDPE was used. As the second resin (resin 2B) constituting the second layer, 50 parts by mass of fossil-derived low-density polyethylene (petroleum-derived LDPE, manufactured by Ube Maruzen Polyethylene Co., Ltd., product name: F224N, density: 0.924 kg / m) was used. 3The resin film had a thickness of 130.0 μm and a density of 922 kg / m. 3 The biomass ratio of the resin film was 23.8%. The area ratio of the region with a molecular weight of 30,000 or less in the first layer was 7.0%, and the dispersity was 2.8.

[0118] Next, a laminate was produced containing the resin film of this example and a base material layer, with the first layer constituting the outermost layer. Using this laminate, a packaging bag with an opening was produced, with the first layer positioned on the innermost surface. The opening of the packaging bag was very easy to open. Such a packaging bag has excellent suitability for filling contents.

[0119] [Example 3] A resin film was prepared and GPC measurements were carried out in the same manner as in Example 1, except that two types of resins were used as the resins constituting the third layer. 80 parts by mass of petrochemical LLDPE was used as the first resin (Resin 3A) constituting the third layer. 20 parts by mass of biomass-derived linear low-density polyethylene (Bio-LLDPE, manufactured by Braskem, trade name: SLL-118, density: 916 kg / m) was used as the second resin (Resin 3B) constituting the third layer. 3 The resin film had a thickness of 130.0 μm and a density of 920 kg / m. 3 The biomass ratio of the resin film was 51.85%. The area ratio of the region with a molecular weight of 30,000 or less in the first layer was 7.0%, and the dispersity was 2.8.

[0120] Next, a laminate was produced containing the resin film of this example and a base material layer, with the first layer constituting the outermost layer. Using this laminate, a packaging bag with an opening was produced, with the first layer positioned on the innermost surface. The opening of the packaging bag was very easy to open. Such a packaging bag has excellent suitability for filling contents.

[0121] [Example 4] Resin films were prepared and GPC measurements were carried out in the same manner as in Example 1, except that two types of resins were used for each of the second and third layers. 50 parts by mass of bio-LDPE was used as resin 2A. 50 parts by mass of petroleum-derived LLDPE was used as resin 2B. 80 parts by mass of petroleum-derived LLDPE was used as resin 3A. 20 parts by mass of bio-LDPE was used as resin 3B. The thicknesses of the first and third layers were 32.5 μm, and the thickness of the second layer was 65.0 μm. The resin film had a thickness of 130.0 μm and a density of 921 kg / m 3 The biomass ratio of the resin film was 28.1%. The area ratio of the region with a molecular weight of 30,000 or less in the first layer was 7.0%, and the dispersity was 2.8.

[0122] Next, a laminate was produced containing the resin film of this example and a base material layer, with the first layer constituting the outermost layer. Using this laminate, a packaging bag with an opening was produced, with the first layer positioned on the innermost surface. The opening of the packaging bag was very easy to open. Such a packaging bag has excellent suitability for filling contents.

[0123] [Example 5] Resin films were prepared and GPC measurements were carried out in the same manner as in Example 1, except that two types of resins were used for each of the second and third layers. 50 parts by mass of bio-LDPE was used as resin 2A. 50 parts by mass of petroleum-derived LLDPE was used as resin 2B. 80 parts by mass of petroleum-derived LLDPE was used as resin 3A. 50 parts by mass of petroleum-derived LLDPE was used as resin 3A. 50 parts by mass of bio-LDPE was used as resin 3B. The thicknesses of the first and third layers were 32.5 μm, and the thickness of the second layer was 65.0 μm. The resin film had a thickness of 130.0 μm and a density of 921 kg / m 3 The biomass ratio of the resin film was 35.6%. The area ratio of the region with a molecular weight of 30,000 or less in the first layer was 7.0%, and the dispersity was 2.8.

[0124] Next, a laminate was produced containing the resin film of this example and a base material layer, with the first layer constituting the outermost layer. Using this laminate, a packaging bag with an opening was produced, with the first layer positioned on the innermost surface. The opening of the packaging bag was very easy to open. Such a packaging bag has excellent suitability for filling contents.

[0125] [Example 6] Resin films were prepared and GPC measurements were carried out in the same manner as in Example 1, except that two types of resins were used for each of the second and third layers. 50 parts by mass of bio-LDPE was used as resin 2A. 50 parts by mass of bio-LLDPE was used as resin 2B. 80 parts by mass of petrochemical LLDPE was used as resin 3A. 20 parts by mass of bio-LDPE was used as resin 3B. The thicknesses of the first and third layers were 32.5 μm, and the thickness of the second layer was 65.0 μm. The resin film had a thickness of 130.0 μm and a density of 920 kg / m 3 The biomass ratio of the resin film was 49.9%. The area ratio of the region with a molecular weight of 30,000 or less in the first layer was 7.0%, and the dispersity was 2.8.

[0126] Next, a laminate was produced containing the resin film of this example and a base material layer, with the first layer constituting the outermost layer. Using this laminate, a packaging bag with an opening was produced, with the first layer positioned on the innermost surface. The opening of the packaging bag was very easy to open. Such a packaging bag has excellent suitability for filling contents.

[0127] [Example 7] Resin films were prepared and GPC measurements were carried out in the same manner as in Example 1, except that two types of resins were used for the first and third layers. 80 parts by mass of petrochemical LLDPE was used for Resin 1A and Resin 3A. 20 parts by mass of bio-LLDPE was used for Resin 1B and Resin 3B. The thicknesses of the first and third layers were 32.5 μm, and the thickness of the second layer was 65.0 μm. The thickness of the resin film was 130.0 μm, and the density was 920 kg / m 3 The biomass ratio of the resin film was 56.2%. The area ratio of the region with a molecular weight of 30,000 or less in the first layer was 8.4%, and the dispersity was 3.4.

[0128] Next, a laminate was produced containing the resin film of this example and a base material layer, with the first layer constituting the outermost layer. Using this laminate, a packaging bag with an opening was produced, with the first layer positioned on the innermost surface. The opening of the packaging bag was very easy to open. Such a packaging bag has excellent suitability for filling contents.

[0129] [Example 8] Resin films were prepared and GPC measurements were carried out in the same manner as in Example 1, except that two types of resins were used for the first and third layers. 50 parts by mass of petrochemical LLDPE was used for Resin 1A and Resin 3A. 50 parts by mass of bio-LLDPE was used for Resin 1B and Resin 3B. The thicknesses of the first and third layers were 32.5 μm, and the thickness of the second layer was 65.0 μm. The thickness of the resin film was 130.0 μm, and the density was 919 kg / m 3 The biomass ratio of the resin film was 69.3%. The area ratio of the region with a molecular weight of 30,000 or less in the first layer was 10.4%, and the dispersity was 4.4.

[0130] Next, a laminate was produced containing the resin film of this example and a base material layer, with the first layer constituting the outermost layer. Using this laminate, a packaging bag with an opening was produced, with the first layer positioned on the innermost surface. The opening of the packaging bag could be easily opened. Such a packaging bag has excellent suitability for filling contents.

[0131] [Example 9] Resin films were prepared and GPC measurements were carried out in the same manner as in Example 1, except that two types of resins were used for each of the first, second, and third layers. 50 parts by mass of petrochemical LLDPE was used for Resin 1A and Resin 3A. 50 parts by mass of bio-LDPE was used for Resin 1B and Resin 3B. 50 parts by mass of bio-LDPE was used for Resin 2A. 50 parts by mass of petrochemical LLDPE was used for Resin 2B. The thicknesses of the first and third layers were 32.5 μm, and the thickness of the second layer was 65.0 μm. The resin film had a thickness of 130.0 μm and a density of 921 kg / m 3 The biomass ratio of the resin film was 32.5%. The area ratio of the region with a molecular weight of 30,000 or less in the first layer was 8.4%, and the dispersity was 3.4.

[0132] Next, a laminate was produced containing the resin film of this example and a base material layer, with the first layer constituting the outermost layer. Using this laminate, a packaging bag with an opening was produced, with the first layer positioned on the innermost surface. The opening of the packaging bag was very easy to open. Such a packaging bag has excellent suitability for filling contents.

[0133] [Example 10] A resin film was prepared and GPC measurements were carried out in the same manner as in Example 1, except that the thickness ratio of the first layer, the second layer, and the third layer was set to 1:3:1. The thicknesses of the first layer and the third layer were 26.0 μm, and the thickness of the second layer was 78.0 μm. The thickness of the resin film was 130.0 μm, and the density was 920 kg / m 3The biomass ratio of the resin film was 57%. The area ratio of the region with a molecular weight of 30,000 or less in the first layer was 7.0%, and the dispersity was 2.8.

[0134] Next, a laminate was produced containing the resin film of this example and a base material layer, with the first layer constituting the outermost layer. Using this laminate, a packaging bag with an opening was produced, with the first layer positioned on the innermost surface. The opening of the packaging bag was very easy to open. Such a packaging bag has excellent suitability for filling contents.

[0135] [Example 11] A film was prepared and GPC measurements were carried out in the same manner as in Example 10, except that the thickness of the resin film was 50.0 μm. The thicknesses of the first and third layers were 10.0 μm, and the thickness of the second layer was 30.0 μm. The density of the resin film was 920 kg / m 3 The biomass ratio of the resin film was 57%. The area ratio of the region with a molecular weight of 30,000 or less in the first layer was 7.0%, and the dispersity was 2.8.

[0136] Next, a laminate was produced containing the resin film of this example and a base material layer, with the first layer constituting the outermost layer. Using this laminate, a packaging bag with an opening was produced, with the first layer positioned on the innermost surface. The opening of the packaging bag was very easy to open. Such a packaging bag has excellent suitability for filling contents.

[0137] [Example 12] A resin film was prepared and subjected to GPC measurement in the same manner as in Example 1, except that the third layer of the resin film was not formed. The thickness of the first layer was 32.5 μm, and the thickness of the second layer was 65.0 μm. The thickness of the resin film was 97.5 μm, and the density was 919 kg / m 3 The biomass ratio of the resin film was 63.3%. The area ratio of the region with a molecular weight of 30,000 or less in the first layer was 7.0%, and the dispersity was 2.8.

[0138] Next, a laminate was produced containing the resin film of this example and a base material layer, with the first layer constituting the outermost layer. Using this laminate, a packaging bag with an opening was produced, with the first layer positioned on the innermost surface. The opening of the packaging bag was very easy to open. Such a packaging bag has excellent suitability for filling contents.

[0139] [Example 13] A resin film was prepared and GPC measurements were carried out in the same manner as in Example 12, except that two types of resins were used as the resins constituting the second layer. 50 parts by mass of bio-LDPE was used as resin 2A. 50 parts by mass of petro-LDPE was used as resin 2B. The thickness of the first layer was 32.5 μm, and the thickness of the second layer was 65.0 μm. The thickness of the resin film was 97.5 μm, and the density was 921 kg / m 3 The biomass ratio of the resin film was 31.7%. The area ratio of the region with a molecular weight of 30,000 or less in the first layer was 7.0%, and the dispersity was 2.8.

[0140] Next, a laminate was produced containing the resin film of this example and a base material layer, with the first layer constituting the outermost layer. Using this laminate, a packaging bag with an opening was produced, with the first layer positioned on the innermost surface. The opening of the packaging bag was very easy to open. Such a packaging bag has excellent suitability for filling contents.

[0141] [Example 14] A resin film was prepared and GPC measurements were carried out in the same manner as in Example 12, except that two types of resins were used as the resins constituting the first layer. 80 parts by mass of petrochemical LLDPE was used as Resin 1A. 20 parts by mass of bio-LDPE was used as Resin 1B. The thickness of the first layer was 32.5 μm, and the thickness of the second layer was 65.0 μm. The thickness of the resin film was 97.5 μm, and the density was 919 kg / m 3 The biomass ratio of the resin film was 69.1%. The area ratio of the region with a molecular weight of 30,000 or less in the first layer was 8.4%, and the dispersity was 3.4.

[0142] Next, a laminate was produced containing the resin film of this example and a base material layer, with the first layer constituting the outermost layer. Using this laminate, a packaging bag with an opening was produced, with the first layer positioned on the innermost surface. The opening of the packaging bag was very easy to open. Such a packaging bag has excellent suitability for filling contents.

[0143] [Example 15] Resin films were prepared and GPC measurements were carried out in the same manner as in Example 1, except that two types of resins were used for each of the first and second layers. 80 parts by mass of petrochemical LLDPE was used as Resin 1A. 20 parts by mass of bio-LDPE was used as Resin 1B. 50 parts by mass of bio-LDPE was used as Resin 2A. 50 parts by mass of petrochemical LDPE was used as Resin 2B. The thickness of the first layer was 32.5 μm, and the thickness of the second layer was 65.0 μm. The thickness of the resin film was 97.5 μm, and the density was 919 kg / m 3 The biomass ratio of the resin film was 37.5%. The area ratio of the region with a molecular weight of 30,000 or less in the first layer was 8.4%, and the dispersity was 3.4.

[0144] Next, a laminate was produced containing the resin film of this example and a base material layer, with the first layer constituting the outermost layer. Using this laminate, a packaging bag with an opening was produced, with the first layer positioned on the innermost surface. The opening of the packaging bag was very easy to open. Such a packaging bag has excellent suitability for filling contents.

[0145] [Comparative Example 1] Resin films were prepared and GPC measurements were carried out in the same manner as in Example 1, except that two types of resins were used for the first and third layers. 20 parts by mass of petrochemical LLDPE was used for Resin 1A and Resin 3A. 80 parts by mass of bio-LLDPE was used for Resin 1A and Resin 3B. The thicknesses of the first and third layers were 32.5 μm, and the thickness of the second layer was 65.0 μm. The resin film had a thickness of 130.0 μm and a density of 918 kg / m 3 The biomass ratio of the resin film was 82.3%. The area ratio of the region with a molecular weight of 30,000 or less in the first layer was 12.4%, and the dispersity was 5.4.

[0146] Next, a laminate was produced containing the resin film of this example and a base material layer, with the first layer constituting the outermost layer. Using this laminate, a packaging bag with an opening was produced, with the first layer positioned on the innermost surface. The opening of the packaging bag was stuck, making it difficult to open.

[0147] Comparative Example 2 A resin film was prepared and GPC measurement was carried out in the same manner as in Example 1, except that 100 parts by mass of bio-LLDPE was used as Resin 1A and Resin 3A. The thicknesses of the first and third layers were 32.5 μm, and the thickness of the second layer was 65.0 μm. The thickness of the resin film was 130 μm, and the density was 918 kg / m 3 The biomass ratio of the resin film was 91%. The area ratio of the region with a molecular weight of 30,000 or less in the first layer was 13.7%, and the dispersity was 6.0.

[0148] Next, a laminate was produced containing the resin film of this example and a base material layer, with the first layer constituting the outermost layer. Using this laminate, a packaging bag with an opening was produced, with the first layer positioned on the innermost surface. The opening of the packaging bag was stuck, making it difficult to open.

[0149] Comparative Example 3 A resin film was prepared and GPC measurements were carried out in the same manner as in Comparative Example 2, except that 100 parts by mass of petrochemical LDPE was used as Resin 2A. The thicknesses of the first and third layers were 32.5 μm, and the thickness of the second layer was 65.0 μm. The thickness of the resin film was 130 μm, and the density was 921 kg / m 3 The biomass ratio of the resin film was 43.5%. The area ratio of the region with a molecular weight of 30,000 or less in the first layer was 13.7%, and the dispersity was 6.0.

[0150] Next, a laminate was produced containing the resin film of this example and a base material layer, with the first layer constituting the outermost layer. Using this laminate, a packaging bag with an opening was produced, with the first layer positioned on the innermost surface. The opening of the packaging bag was stuck, making it difficult to open.

[0151] FIG. 9 shows the results of Examples 1 to 15 and Comparative Examples 1 to 3. [Explanation of symbols]

[0152] 10: Resin film 11: 1st layer 12:Second layer 13: Thermoplastic resin layer 14:Third layer 15: Thermoplastic resin layer 20: Laminate 21: Base material layer 30: Packaging bag 31: Torso 32: Bottom

Claims

1. A packaging product comprising a laminate, the laminate includes a resin film and a base layer, the resin film comprises a first layer, a second layer, and a third layer; the first layer constitutes at least one outermost layer of the resin film; the third layer constitutes the other outermost layer of the resin film, the first layer and the second layer are laminated together directly or via a thermoplastic resin layer, the second layer and the third layer are laminated together directly or via a thermoplastic resin layer, the resin film contains linear low-density polyethylene and low-density polyethylene, the resin film contains biomass-derived polyethylene, the first layer comprises fossil fuel-derived linear low-density polyethylene; the third layer comprises biomass-derived linear low-density polyethylene or biomass-derived low-density polyethylene; the area ratio of a region of a molecular weight of 30,000 or less in a molecular weight distribution curve obtained by GPC measurement of the first layer in accordance with JIS K 7252-1:2008 is 12.0% or less of the total peak area; A packaged product, wherein the first layer is located on the innermost surface of the packaged product.

2. 10. The packaging product of claim 1, wherein the second layer comprises biomass-derived polyethylene.

3. 3. The packaging product of claim 1 or 2, wherein the second layer comprises low density polyethylene.

4. The packaging product of any one of claims 1 to 3, wherein the second layer comprises biomass-derived low-density polyethylene.

5. The packaging product according to any one of claims 1 to 4, wherein the first layer has a dispersity of 5.0 or less.

6. A packaging product described in any one of claims 1 to 5, wherein the biomass content of the resin film is 5% or more.

7. The packaging product of any one of claims 1 to 6, wherein the third layer comprises linear low density polyethylene.

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