Self-standing packaging bag and packaged article

Abstract

To provide a self-standing packaging bag which has excellent hygiene and strength and contains few foreign matters.SOLUTION: A self-standing packaging bag includes a pair of body films facing each other and a bottom film, and contains polyolefin, where each of the pair of body films contains petroleum-derived polyolefin, and the bottom film contains material-recycled polyolefin.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a self-standing packaging bag and a packaged article. [Background technology]

[0002] A packaged article formed by filling a self-standing packaging bag such as a standing pouch with contents can stand on its own. Therefore, a self-standing packaged article can be stored in a box in a self-standing state, for example, and is therefore easy to pack. Furthermore, a self-standing packaged article can be displayed attractively on a store shelf, for example, and is also easy to display. A self-standing packaging bag described in Patent Document 1 is known. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2001-206384 Summary of the Invention [Problem to be solved by the invention]

[0004] Since self-standing packaging bags such as standing pouches are filled with food, medicine, etc., they are required to be hygienic and contain little foreign matter. They are also required to have sufficient strength to prevent the contents from spilling.

[0005] Therefore, one aspect of the present invention aims to provide a self-standing packaging bag that has excellent hygiene and strength and contains little foreign matter. Another aspect of the present invention aims to provide a packaged article using the self-standing packaging bag. [Means for solving the problem]

[0006] One aspect of the present invention includes the following [1] to

[20] . [1] A self-standing packaging bag comprising a pair of opposing main films and a bottom film, and containing polyolefin, Each of the pair of main films contains a petroleum-derived polyolefin, The self-standing packaging bag, wherein the bottom film contains recycled polyolefin. [2] Each of the pair of main films has a first base material layer, a first intermediate layer, and a first sealant layer, The self-standing packaging bag according to [1], wherein the first base layer contains the petroleum-derived polyolefin. [3] Each of the pair of main films has a first base material layer, a first intermediate layer, and a first sealant layer, The self-standing packaging bag according to [1] or [2], wherein the first intermediate layer contains the petroleum-derived polyolefin. [4] Each of the pair of main films has a first base material layer, a first intermediate layer, and a first sealant layer, The self-standing packaging bag according to any one of [1] to [3], wherein the first sealant layer contains the petroleum-derived polyolefin. [5] The bottom film has a second substrate layer, a second intermediate layer, and a second sealant layer; The self-standing packaging bag according to any one of [1] to [4], wherein the second base material layer contains the material recycled polyolefin. [6] The bottom film has a second substrate layer, a second intermediate layer, and a second sealant layer; The self-standing packaging bag according to any one of [1] to [5], wherein the second intermediate layer contains the material recycled polyolefin. [7] The bottom film has a second substrate layer, a second intermediate layer, and a second sealant layer; The self-standing packaging bag according to any one of [1] to [6], wherein the second sealant layer contains the material recycled polyolefin. [8] The self-standing packaging bag according to any one of [1] to [7], wherein the content of the material recycled polyolefin is 1% by volume or more based on the total volume of the self-standing packaging bag. [9] The self-standing packaging bag according to any one of [1] to [8], wherein the content of the material recycled polyolefin is 1% by mass or more based on the total mass of the self-standing packaging bag.

[10] The self-standing packaging bag according to any one of [1] to [9], wherein the content of the material recycled polyolefin is 5% by volume or more based on the total volume of the self-standing packaging bag.

[11] The self-standing packaging bag according to any one of [1] to

[10] , wherein the content of the material recycled polyolefin is 5% by mass or more based on the total mass of the self-standing packaging bag.

[12] The self-standing packaging bag according to any one of [1] to

[11] , wherein the polyolefin is a post-consumer recycled polyolefin.

[13] The self-standing packaging bag according to any one of [1] to

[12] , wherein the content of the polyolefin is 80% by volume or more based on the total volume of the self-standing packaging bag.

[14] The self-standing packaging bag according to any one of [1] to

[13] , wherein the content of the polyolefin is 80% by mass or more based on the total mass of the self-standing packaging bag.

[15] The self-standing packaging bag according to any one of [1] to

[14] , wherein the pair of main body films and the bottom film contain the same material.

[16] The self-standing packaging bag according to any one of [1] to

[15] , wherein the bottom film contains at least one of a petroleum-derived polyolefin and a biomass-derived polyolefin.

[17] The pair of main body films and the bottom film each have a multilayer structure, The self-standing packaging bag according to any one of [1] to

[16] , wherein the innermost layer of the multilayer structure is made of at least one of petroleum-derived polyolefin and biomass-derived polyolefin.

[18] The self-standing packaging bag according to any one of [2] to [4], further comprising a gas barrier layer between the first base material layer and the first sealant layer.

[19] The self-standing packaging bag according to any one of [5] to [7], further comprising a gas barrier layer between the second base material layer and the second sealant layer.

[20] A self-standing packaging bag according to any one of [1] to

[19] , Contents contained in the self-standing packaging bag; A packaging article comprising: [Effects of the Invention]

[0007] According to the present invention, it is possible to provide a self-standing packaging bag that has excellent hygiene and strength and contains little foreign matter. Furthermore, according to the present invention, it is possible to provide a packaged article using the self-standing packaging bag. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a front view of a packaged article according to one embodiment of the present invention. [Figure 2] FIG. 2 is a cross-sectional view of the bottom of the packaged article of FIG. [Figure 3] 3 is a cross-sectional view of the bottom of the self-standing packaging bag used in the packaged article of FIG. 1. FIG. [Figure 4] FIG. 4 is a cross-sectional view of the main body film used in the self-standing packaging bag of FIG. [Figure 5] FIG. 5 is a cross-sectional view of the bottom film used in the self-standing packaging bag of FIG. [Figure 6] FIG. 6 is a front view of a packaged article according to a modified example. DETAILED DESCRIPTION OF THE INVENTION

[0009] Preferred embodiments of the present invention will be described in detail below. However, the present invention is not limited to the following embodiments. In the drawings, the same or corresponding parts are designated by the same reference numerals, and redundant explanations will be omitted.

[0010] [Self-supporting packaging bags, packaging goods] Fig. 1 is a front view of a packaged article according to one embodiment of the present invention. In the packaged article 100 shown in Fig. 1, the end of the packaged article 100 where heat-sealed portion HS1 is formed is called the side, the end where heat-sealed portion HS2A is formed is called the bottom, and the end where heat-sealed portion HS3 is formed is called the top. Fig. 2 is a cross-sectional view of the bottom of the packaged article shown in Fig. 1.

[0011] The packaged article 100 shown in FIGS. 1 and 2 comprises a self-standing packaging bag 110 and contents 120 contained in the self-standing packaging bag 110.

[0012] The self-standing packaging bag 110 has a pair of main body films 111A and 111B and a bottom film 112.

[0013] As will be described later, each of the main films 111A, 111B and the bottom film 112 is a laminate having a base layer and a sealant layer provided on the base layer.

[0014] 3 is a cross-sectional view of the bottom of the self-standing packaging bag 110 used in the packaged article 100, showing the self-standing packaging bag 110 before it is filled with the contents 120. In the self-standing packaging bag 110 before it is filled with the contents 120, the main body films 111A and 111B are arranged so that their sealant layers face each other. The bottom film 112 is arranged between the main body films 111A and 111B, and is folded in half so as to form a mountain fold when viewed from the sealant layer side of the bottom film 112. The end of the bottom film 112 opposite the mountain fold MF is heat-sealed to the ends of the main body films 111A and 111B (the ends on the bottom side of the self-standing packaging bag 110).

[0015] The main body films 111A and 111B are heat-sealed to each other at their sides from the mountain fold MF of the bottom film 112 to the ends of the main body films 111A and 111B, thereby forming heat-sealed portions HS1 on both sides of the main body films 111A and 111B.

[0016] The bottom film 112 is heat-sealed to the main body films 111A and 111B at ends other than the mountain fold MF. Specifically, one of the two portions of the bottom film 112 defined by the mountain fold MF is heat-sealed to the main body film 111A at an end other than the mountain fold MF, forming a heat-sealed portion HS2A. The other of the two portions of the bottom film 112 defined by the mountain fold MF is heat-sealed to the main body film 111B at an end other than the mountain fold MF, forming a heat-sealed portion HS2B. The heat-sealed portions HS2A and HS2B of the bottom film 112 are bonded to both ends on the side of the bottom of the self-standing packaging bag 110.

[0017] Heat-sealed portions HS1 and HS4 shown in Fig. 1 are portions heat-sealed by a side seal and a point seal, respectively, which will be described later. Heat-sealed portions HS2A shown in Figs. 1 to 3 and heat-sealed portions HS2B shown in Figs. 2 and 3 are portions heat-sealed by a bottom seal, which will be described later.

[0018] In packaged article 100, in which content 120 is accommodated in self-standing packaging bag 110, main body films 111A and 111B are further heat-sealed at their upper portions, thereby forming heat-sealed portions HS3 at the upper positions of main body films 111A and 111B.

[0019] The self-standing packaging pouch 110 has an easy-to-open portion formed at the upper corner thereof. The easy-to-open portion is, for example, a notch.

[0020] The self-standing packaging bag 110 may have an easy-open portion formed in a portion other than the corners of the upper portion. For example, the self-standing packaging bag 110 may have an easy-open portion formed in the center of the upper portion. The self-standing packaging bag 110 may further include a spout member and a lid member at the upper portion. For example, like the self-standing packaging bag 110 of the packaged article 100A shown in FIG. 6, the self-standing packaging bag 110 may have a spout 113, which is a member for extracting the contents, interposed between the main body films 111A and 111B at the upper portion of the self-standing packaging bag 110, and a cap 114, which is a member for welding and sealing the spout 113, fitted or screwed onto the opening of the spout 113.

[0021] The contents 120 are, for example, liquids or mixtures of liquids and solids, and may include, for example, food, shampoo, conditioner, body wash, detergent, or medicine.

[0022] Although there is no limit to the volume of the contents 120, the volume of the contents 120 is preferably within the range of 0.2 to 4.0 L. The volume of the contents 120 is more preferably 0.8 L or more. Furthermore, the volume of the contents 120 is more preferably 3.0 L or less.

[0023] Each of the pair of main films 111 may have a first base material layer 11, a first intermediate layer 18, and a first sealant layer 12. The bottom film 112 may have a second base material layer 21, a second intermediate layer 28, and a second sealant layer 22. In the pair of main films 111, at least one of the first base material layer 11, the first intermediate layer 18, and the first sealant layer 12 may be a polyolefin film. In the bottom film 112, at least one of the second base material layer 21, the second intermediate layer 28, and the second sealant layer 22 may be a polyolefin film. Each of the pair of main films contains a petroleum-derived polyolefin, and the bottom film contains a recycled resin or a material recycled polyolefin as the recycled polyolefin.

[0024] Material-recycled polyolefins refer to polyolefins recovered by crushing and melting discarded polyolefin materials. One example of material-recycled polyolefins is polyolefins made by crushing discarded polyolefin film, cleaning the crushed film with alkali to remove dirt and foreign matter from the film surface, and then drying the crushed film at high temperature and reduced pressure to disperse contaminants remaining inside the film, decontaminating it and making it reusable. Material-recycled polyolefins emit less carbon dioxide during production than chemically recycled polyolefins and petroleum-derived polyolefins. Furthermore, material-recycled polyolefins are easier to source than chemically recycled polyolefins.

[0025] Chemically recycled polyolefin refers to polyolefins that are made reusable by first converting discarded resins into monomers via gasification, liquefaction, and refined naphtha, or by depolymerization, depending on the material's characteristics, resulting in lower molecular weights and then polymerizing them. Compared to material-recycled polyolefins, chemically recycled polyolefins are less likely to be contaminated with foreign matter such as impurities, gels, and aggregates. Therefore, chemically recycled polyolefins are more hygienic than material-recycled polyolefins. Furthermore, unlike material-recycled polyolefins, chemically recycled polyolefins are not subject to heat treatments such as heat melting after the recycling process, making them less susceptible to thermal degradation. Therefore, compared to material-recycled polyolefins, chemically recycled polyolefins are less susceptible to odors and foreign matter due to thermal degradation, and are less susceptible to defects such as missing characters during the printing process and adhesive defects (lamination lift) during the lamination process due to foreign matter. Furthermore, compared to material recycled polyolefins, chemically recycled polyolefins are less likely to cause tearing of a standing pouch filled with contents due to a foreign object when dropped.

[0026] Polyolefins that have not been material-recycled or chemically recycled may be petroleum-derived polyolefins obtained using petroleum-derived raw material monomers, or may be biomass-derived polyolefins. Biomass-derived polyolefins refer to polyolefins made from renewable organic resources such as plants. Examples of biomass-derived polyolefins that can be used include green polyethylene (manufactured by Braskem).

[0027] (recycled resin content) The higher the recycled polyolefin content (usage ratio) in the self-standing packaging bag, the more the environmental impact can be reduced. The recycled polyolefin content in the self-standing packaging bag may be 10% by mass or more, based on the total mass of the self-standing packaging bag, and is preferably 20% by mass or more, more preferably 25% by mass or more, even more preferably 30% by mass or more, and particularly preferably 40% by mass or more. The recycled polyolefin content in the self-standing packaging bag may be 10% by volume or more, based on the total volume of the self-standing packaging bag, and is preferably 20% by volume or more, more preferably 25% by volume or more, even more preferably 30% by volume or more, and particularly preferably 40% by volume or more. The recycled polyolefin content (mass % or volume %) may be the ratio of the thickness of the layer using recycled polyolefin to the total thickness of the main film and bottom film that make up the self-standing packaging bag.

[0028] (Polyolefin content) The polyolefin content in the self-standing packaging bag is preferably 80% by volume or more or 80% by mass or more, more preferably 85% by volume or more or 85% by mass or more, and particularly preferably 90% by volume or more or 90% by mass or more, based on the total volume or mass of the self-standing packaging bag. When the polyolefin content in the self-standing packaging bag is 80% by volume or more or 80% by mass or more, the polyolefin content in the entire self-standing packaging bag is high, thereby further improving the recyclability of the self-standing packaging bag. In the case where the bottom film used in the self-standing packaging bag contains recycled polyolefin and the second base layer, second intermediate layer, and second sealant layer are a mixture of recycled polyolefin and non-recycled polyolefin such as petroleum-derived polyolefin or biomass-derived polyolefin, the mass of the polyolefin in each of the second base layer, second intermediate layer, and second sealant layer is calculated according to the mass ratio, and the recycled polyolefin content (% by mass) in the self-standing packaging bag is calculated.

[0029] The recycled polyolefin may be a post-consumer recycled (PCR) polyolefin, a post-industrial recycled (PIR) polyolefin, or a combination of a PCR polyolefin and a PIR polyolefin. PCR can be secured in large quantities on the market, which can reduce the cost of the pair of body films and the bottom film.

[0030] From the viewpoint of reducing the environmental load, the content of biomass-derived polyolefin in the self-standing packaging bag is preferably 10% by volume or more or 10% by mass or more, more preferably 20% by volume or more or 20% by mass or more. The content of biomass-derived polyolefin in the self-standing packaging bag may be 0% by volume or 0% by mass.

[0031] The content of material recycled polyolefin in the self-standing packaging bag is preferably 1% by volume or more or 1% by mass or more, and more preferably 5% by volume or more or 5% by mass or more, from the viewpoint of providing the self-standing packaging bag with better hygiene and strength and with less foreign matter.

[0032] <Main body film> 4 is a cross-sectional view of main body film 111 (either main body film 111A or 111B) used in self-standing packaging pouch 110. Main body film 111 includes, in this order, first protective layer 16, first base material layer 11, first printed layer 14, first adhesive layer 13A, first intermediate layer 18, first inorganic compound layer 15, first coating layer 17, first adhesive layer 13B, and first sealant layer 12.

[0033] The main body film 111 contains a petroleum-derived polyolefin. Examples of polyolefins include polyethylene and polypropylene. Hereinafter, the polyolefin, polyethylene, polypropylene, etc. contained in each layer of the main body film 111 may or may not be petroleum-derived.

[0034] The content of petroleum-derived polyolefin in main film 111 may be 10% by mass or more, preferably 20% by mass or more, more preferably 25% by mass or more, even more preferably 30% by mass or more, and particularly preferably 40% by mass or more, based on the total mass of main film 111. The content of petroleum-derived polyolefin in main film 111 may be 10% by volume or more, preferably 20% by volume or more, more preferably 30% by volume or more, and particularly preferably 40% by volume or more, based on the total volume of main film 111.

[0035] The polyolefin content in the main film 111 is preferably 80% by volume or more or 80% by mass or more, more preferably 85% by volume or more or 85% by mass or more, and particularly preferably 90% by volume or more or 90% by mass or more, based on the total volume or total mass of the main film 111.

[0036] (1st base layer) The first base layer 11 may contain polyolefin, polyethylene, or polypropylene. The polyolefin film may contain a resin made of polyolefin. The first base layer 11 may contain petroleum-derived polyolefin, or non-petroleum-derived polyolefin.

[0037] The polyethylene contained in the first base layer 11 may be an ethylene homopolymer or a copolymer of ethylene and another monomer. When the polyethylene is a copolymer of ethylene and another monomer, the ethylene content in the copolymer is, for example, 80 mol% or more. The other monomer is, for example, an α-olefin. Examples of α-olefins include propylene, 1-butene, 1-pentene, 1-hexene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, 1-eicosene, 3-methyl-1-butene, 4-methyl-1-pentene, and 6-methyl-1-heptene. Examples of polyethylene include homopolyethylene, block polyethylene, and random polyethylene.

[0038] The polyethylene may be a copolymer of ethylene and at least one selected from the group consisting of vinyl acetate and acrylic esters, or a copolymer of ethylene and at least one selected from the group consisting of vinyl acetate, a saponified product thereof, (meth)acrylic acid, and an esterified product thereof.

[0039] The polyethylene may be high density polyethylene (HDPE), medium density polyethylene (MDPE), low density polyethylene (LDPE), linear low density polyethylene (LLDPE), or very low density polyethylene (VLDPE). It is more preferable that at least HDPE or MDPE is included to increase rigidity.

[0040] High density polyethylene has a density of 0.942 g / cm 3Medium density polyethylene has a density of 0.930 g / cm or more. 3 More than 0.942g / cm 3 Low-density polyethylene is polyethylene with a density of less than 0.910 g / cm 3 More than 0.930g / cm 3 Linear low-density polyethylene is polyethylene with a density of less than 0.910 g / cm 3 Over 0.930cm 3 Ultra-low density polyethylene is polyethylene with a density of less than 0.910 g / cm 3 The density is a value obtained by a method in accordance with JIS K7112:1999. Polypropylene may be a homopolymer of propylene or a copolymer of propylene and another monomer. Examples of the other monomer include α-olefins. Examples of α-olefins include ethylene, 1-butene, 1-pentene, 1-hexene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, 1-eicosene, 3-methyl-1-butene, 4-methyl-1-pentene, and 6-methyl-1-heptene. Examples of polypropylene include homopolypropylene, block polypropylene, and random polypropylene.

[0041] The polyolefin may be a non-recycled polyolefin, a chemically recycled polyolefin, or a mixture thereof. The non-recycled polyolefin may be a petroleum-derived polyolefin, a biomass-derived polyolefin, or a mixture thereof, and from the viewpoint of reducing the environmental load, a biomass-derived polyolefin is preferred.

[0042] From the viewpoints of achieving better hygiene and increased strength, the content of petroleum-derived polyolefin in first base material layer 11 is more preferably 10% by volume or more, 30% by volume or more, 50% by volume or more, or 80% by volume or more, based on the total volume of first base material layer 11. According to one example, first base material layer 11 is made of petroleum-derived polyolefin. According to another example, first base material layer 11 is made of petroleum-derived polyolefin, non-petroleum-derived polyolefin, and additives. It consists of:

[0043] The first substrate layer 11 may have a single-layer structure or a multi-layer structure. When the first substrate layer 11 has a multi-layer structure, at least one layer of the first substrate layer 11 may contain a petroleum-derived polyolefin or a recycled polyolefin.

[0044] The first base layer 11 may contain other resins as needed, as long as the content of petroleum-derived polyolefin in the self-standing packaging bag is 10% by volume or more or 10% by mass or more. The first base layer 11 may be a layer formed by co-extrusion multilayer film formation of an ethylene-vinyl alcohol copolymer layer or a polyamide layer using an adhesive resin or the like, and then stretching the film. More specifically, examples include a three-type five-layer substrate consisting of petroleum-derived polyolefin / adhesive resin / ethylene-vinyl alcohol copolymer / adhesive resin / material recycled polyolefin; a three-type three-layer substrate consisting of petroleum-derived polyolefin / adhesive resin / ethylene-vinyl alcohol copolymer; a multilayer substrate consisting of petroleum-derived (natural) polyolefin / recycled polyolefin / petroleum-derived (natural) polyolefin, petroleum-derived (natural) polyolefin / other polyolefin / recycled polyolefin / other polyolefin / petroleum-derived (natural) polyolefin, etc. When the first base layer 11 has a multilayer structure, the specific gravities of the same materials may differ depending on the function.

[0045] The first base layer 11 may further contain additives, such as a crosslinking agent, an antioxidant, an antiblocking agent, a lubricant (slip agent), an ultraviolet absorber, a light stabilizer, a filler, a reinforcing agent, an antistatic agent, a pigment, and a modifying resin.

[0046] When the first base material layer 11 is mainly composed of polyethylene, the melting point is preferably in the range of 100 to 140° C., and more preferably in the range of 120 to 140° C. When the first base material layer 11 is mainly composed of polypropylene, the melting point is preferably in the range of 120 to 175° C. The melting point is measured by a method in accordance with JIS K7121-1987.

[0047] The first base layer 11 may be a non-stretched film or a stretched film. The first base layer 11 is preferably a stretched film. When the first base layer 11 is a stretched film, the first base layer 11 may be a uniaxially stretched film or a biaxially stretched film. When the first base layer 11 is a stretched film, the following effects are achieved. When the first base layer 11 is a uniaxially stretched film, it is possible to improve tear resistance, heat resistance, and the like. When the first base layer 11 is a biaxially stretched film, mechanical strength and dimensional stability are improved, and printability is improved.

[0048] Whether a stretched film is uniaxially or biaxially stretched can be determined by in-plane measurement using wide-angle X-ray diffraction, as described in detail below. The X-ray diffraction pattern obtained by in-plane measurement contains information about the degree of orientation of molecular chains present in the film plane.

[0049] When a polymer film is uniaxially stretched, a higher-order structure called a shish kebab structure appears. The shish kebab structure consists of a shish structure, which is an extended chain crystal, and a kebab structure, which is a lamellar crystal. In a uniaxially stretched film, this higher-order structure is arranged with a high degree of order, and the X-ray diffraction pattern obtained by the above measurement of the uniaxially stretched film contains a sharp diffraction peak. In other words, when the above measurement is performed on a uniaxially stretched film, a clear diffraction peak appears. Note that a "clear diffraction peak" means a diffraction peak with a half-width of less than 10°.

[0050] In contrast, in the production of biaxially stretched film, the film is stretched in a specific direction, and then stretched in a direction perpendicular to the first direction. Therefore, although the above-mentioned high-order structure is generated by the first stretching, the high-order structure is destroyed by the second stretching. Therefore, when in-plane measurements are performed on biaxially stretched film, the diffraction peaks in the resulting X-ray diffraction pattern are broad. In other words, when in-plane measurements are performed on biaxially stretched film, clear diffraction peaks do not appear.

[0051] As described above, the X-ray diffraction patterns obtained by in-plane measurement differ between uniaxially stretched films and biaxially stretched films. Therefore, it is possible to determine whether a stretched film is uniaxially stretched or biaxially stretched based on the in-plane measurement.

[0052] When the first base layer 11 is a film, the film can be produced by a known production method such as a casting method or an inflation method. The first base layer 11 may be a polyethylene film with a multilayer structure obtained by co-extrusion of polyethylenes with different densities. A stretched film can be obtained, for example, by stretching a film obtained by forming polyethylene into a film by a T-die method or an inflation method.

[0053] The haze of the first base layer 11 is preferably 20% or less, and more preferably 10% or less. The haze is measured by a method in accordance with JIS K7136:2000.

[0054] The thickness of the first base layer 11 is preferably in the range of 10 to 100 μm. The thickness of the first base layer 11 may be, for example, 10 to 50 μm, 15 to 50 μm, or 12 to 35 μm. When the first base layer 11 is 10 μm or more, the strength of the main body film 111 is superior. When the first base layer 11 is 100 μm or less, the processability of the main body film 111 is superior.

[0055] It is preferable that the first base material layer 11 is surface-treated. By surface-treating the first base material layer 11, the adhesion between the first base material layer 11 and the layer adjacent to the first base material layer 11 can be improved.

[0056] There is no particular limitation on the method for treating the surface of the first base material layer 11. Examples of surface treatment methods include physical treatments such as corona discharge treatment, ozone treatment, low-temperature plasma treatment using oxygen gas and / or nitrogen gas, and glow discharge treatment, as well as chemical treatments such as oxidation treatment using chemicals. A coating layer such as an adhesive layer may be provided on the surface of the first base material layer 11.

[0057] The first substrate layer 11 may be colored, for example, white.

[0058] (First sealant layer) The first sealant layer 12 faces the first base layer 11. The first sealant layer 12 may contain a polyolefin, such as polyethylene or polypropylene. The polyolefin film contains a resin made of polyolefin. The first sealant layer 12 may contain a petroleum-derived recycled polyolefin or a non-petroleum-derived polyolefin. The polyolefin contained in the first sealant layer 12 can be the same as that contained in the first base layer 11. When the first sealant layer 12 contains polyethylene, the polyethylene is preferably unstretched low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), or very low-density polyethylene (VLDPE), and more preferably linear low-density polyethylene. When the first sealant layer 12 contains polypropylene, the polypropylene is preferably unstretched propylene.

[0059] In one example, the first sealant layer 12 is made of a petroleum-derived polyolefin. In another example, the first sealant layer 12 is made of a petroleum-derived polyolefin, a non-petroleum-derived polyolefin, and an additive.

[0060] The first sealant layer 12 preferably has a melting point lower than that of the first base material layer 11. In this case, during heat sealing, it is possible to heat-seal the sealant layer 13 while suppressing melting of the first base material layer 11.

[0061] The first sealant layer 12 may further contain additives such as a flame retardant, a slip agent, an antiblocking agent, an antioxidant, a light stabilizer, a tackifier, an antistatic agent, a light-shielding pigment, etc. The first sealant layer 12 may further contain the additives contained in the first base material layer 11.

[0062] The content of polyethylene and / or polypropylene in the first sealant layer 12 is preferably 50% by volume or more, and more preferably 80% by volume or more, based on the total volume of the first sealant layer 12. In one example, the first sealant layer 12 is made of polyethylene and / or polypropylene. In another example, the first sealant layer 12 is made of polyethylene and / or polypropylene and an additive.

[0063] The first sealant layer 12 may have a single-layer structure or a multi-layer structure. When the first sealant layer 12 has a single-layer structure, the first sealant layer 12 may be a layer containing a petroleum-derived polyolefin or a layer containing a recycled polyolefin. When contents are placed in a packaging container obtained using the main film 10, the first sealant layer 12 is the layer that comes into contact with the contents. To prevent the recycled polyolefin film from coming into contact with the contents, the first sealant layer 12 may be a layer containing a non-recycled polyolefin. If the first sealant layer 12 is a layer containing a non-recycled polyolefin, the possibility of foreign matter such as impurities, gels, and aggregates being transferred to the contents upon heating during retort or boiling of the packaging container can be further reduced, and the main film 10 can be used safely to package contents such as food.

[0064] When the first sealant layer 12 has a multi-layer structure, all of the layers may contain a petroleum-derived polyolefin, or may contain a non-recycled polyolefin film, or at least one of the layers may contain a petroleum-derived polyolefin.

[0065] When at least one layer in first sealant layer 12 contains a petroleum-derived polyolefin, it is preferable that the layer located farthest from first base layer 11 contains a petroleum-derived polyolefin.

[0066] When the first sealant layer has three layers, it may be composed of an outer layer, an intermediate layer, and an inner layer, where the outer layer and the inner layer are layers made of petroleum-derived polyolefin, and the intermediate layer may be a layer containing recycled polyolefin.

[0067] The first sealant layer 12 may be transparent or opaque. If the first sealant layer 12 is opaque, it may be white, black, gray, sepia, or the like. If the first sealant layer 12 is opaque, it may have a single opaque layer, two or more opaque layers, or a combination of a transparent layer and an opaque layer. If the first sealant layer 12 is transparent and the main film 111 is also transparent, using the transparent main film 111 as the main films 111A and 111B of the self-standing packaging bag 110 makes it easier to view the contents 120. If the first sealant layer 12 is opaque and the main film 111 is also opaque, using the opaque main film 111 as the main films 111A and 111B of the self-standing packaging bag 110 makes it easier to view the image displayed by the first printed layer 14. When the first sealant layer 12 is white, the image displayed by the first print layer 14 becomes particularly easy to see.

[0068] The first sealant layer 12 can be colored white, gray, black, or the like by mixing a pigment or the like into the material resin constituting the first sealant layer 12. For example, the first sealant layer 12 becomes white when titanium oxide is mixed into the material resin, becomes black when carbon black is mixed into the material resin, and becomes gray when both titanium oxide and carbon black are mixed into the material resin. The light-blocking properties of the first sealant layer 12 are improved by making the first sealant layer 12 black, gray, or sepia. When the light-blocking properties of the first sealant layer 12 are excellent, the first sealant layer 12 contains, for example, carbon black.

[0069] The thickness of the first sealant layer 12 is not particularly limited and can be appropriately set taking into consideration the shape of the packaging bag to be manufactured, the mass of the contents to be contained, etc. The thickness of the first sealant layer 12 is preferably 30 μm or more from the viewpoint of achieving higher strength, and more preferably 60 μm or more from the viewpoint of easily retaining the contents. The thickness of the first sealant layer 12 is preferably 250 μm or less, more preferably 200 μm or less, from the viewpoints of excellent bag-making efficiency and cost.

[0070] The first sealant layer 12 may be an unstretched polyolefin resin film, or may be a layer formed by melt-extrusion of polyolefin.

[0071] (1st printing layer) The first printed layer 14 is provided on the surface of the first base layer 11 facing the first sealant layer 12. The position of the first printed layer in the main film is not limited. That is, the first printed layer may be provided on the surface of the first base layer, or at any position between the first base layer and the first sealant layer. For example, the first printed layer may be provided on either side of the first intermediate layer. The main film may also include multiple first printed layers. When the first printed layer is provided on the inner surface of the first base layer 11, the first printed layer is protected by the first base layer 11, preventing deterioration of the first printed layer. When the first printed layer is provided on the outer surface of the first base layer 11 and is the outermost layer of the main film 10, the first printed layer can be easily removed when recycling a package including the main film 10 after disposal.

[0072] The printing ink used for the first printing layer 14 is not particularly limited as long as it has adhesion to polyolefin. The first printing layer 14 is composed of, for example, a printing ink containing a resin such as a urethane-based, acrylic-based, nitrocellulose-based, rubber-based, or vinyl chloride-based resin, to which additives such as a pigment, plasticizer, desiccant, and stabilizer have been added. It is preferable to use a biomass-derived ink. Examples of printing methods that can be used include well-known printing methods such as offset printing, gravure printing, flexographic printing, and silk screen printing, as well as well-known coating methods such as roll coating, knife-edge coating, and gravure coating. Light-blocking inks are also preferably used. Examples of light-blocking inks include white ink, black ink, silver ink, and sepia ink.

[0073] The printing ink may be either an aqueous ink or an oil-based ink. The printing ink is preferably an aqueous ink. Because an aqueous ink uses water or alcohol as a solvent, it can further reduce the environmental impact. In particular, when the adhesive is a solventless adhesive, using an aqueous ink as the printing ink can significantly reduce the environmental impact. The printing ink may or may not be a biomass ink. From the perspective of reducing the environmental impact, the printing ink is preferably a biomass ink. Here, biomass ink refers to an ink containing components obtained from biological resources (biomass) such as cotton, pulp, rice bran, vegetable oil, and angiosperm seeds. The printing ink may be a recycled ink obtained by collecting and recycling used ink, or a non-recycled ink, but from the perspective of reducing the environmental impact, recycled ink is preferred.

[0074] Easily recyclable inks can also be used as printing inks. By using easily recyclable inks, it becomes possible to easily recycle the self-standing packaging bags after they have been discarded. Specific examples of easily recyclable inks include "SunSpectro Solvawash" manufactured by DIC Corporation.

[0075] (First middle class) The first intermediate layer 18 is provided between the first base material layer 11 and the first sealant layer 12. Here, the first intermediate layer 18 is provided between the first base material layer 11 and the first sealant layer 12 so that the first printed layer 14 is interposed between the first base material layer 11 and the first intermediate layer 18. The main body film does not necessarily have to have a first intermediate layer.

[0076] The first intermediate layer 18 may contain a polyolefin, polyethylene, or polypropylene. The polyolefin film contains a resin made of polyolefin. The polyolefin may be, for example, the same polyolefin or polyethylene contained in the first base layer 11. The first intermediate layer 18 may further contain an additive that the first base layer 11 may contain. The first intermediate layer 18 may contain a petroleum-derived polyolefin, or a non-petroleum-derived polyolefin.

[0077] In one example, first intermediate layer 18 is made of a petroleum-derived polyolefin. In another example, first intermediate layer 18 is made of a petroleum-derived polyolefin, a non-petroleum-derived polyolefin, and an additive.

[0078] In one example, the first intermediate layer 18 is made of polyethylene and / or polypropylene. In another example, the first intermediate layer 18 is made of polyethylene and / or polypropylene and an additive.

[0079] The melting point of the first intermediate layer 18 is preferably in the range of 100 to 140°C when the main component is polyethylene, and more preferably in the range of 120 to 140°C. When the main component is polypropylene, it is preferably in the range of 120 to 175°C.

[0080] The first intermediate layer 18 may be a non-stretched film or a stretched film. When the first intermediate layer 18 is a stretched film, the first intermediate layer 18 may be a uniaxially stretched film or a biaxially stretched film. When the first intermediate layer 18 is a stretched film, the following effects are achieved. That is, when the first intermediate layer 18 is uniaxially stretched, it is possible to improve tear resistance, heat resistance, and the like. When the first intermediate layer 18 is a biaxially stretched film, it improves mechanical strength and dimensional stability, and improves printability.

[0081] Whether a stretched film is uniaxially or biaxially stretched can be determined by in-plane measurement using wide-angle X-ray diffraction, as described in detail below. The X-ray diffraction pattern obtained by in-plane measurement contains information about the degree of orientation of molecular chains present in the film plane.

[0082] When a polymer film is uniaxially stretched, a higher-order structure called a shish kebab structure appears. The shish kebab structure consists of a shish structure, which is an extended chain crystal, and a kebab structure, which is a lamellar crystal. In a uniaxially stretched film, this higher-order structure is arranged with a high degree of order, and the X-ray diffraction pattern obtained by the above measurement of the uniaxially stretched film contains a sharp diffraction peak. In other words, when the above measurement is performed on a uniaxially stretched film, a clear diffraction peak appears. Note that a "clear diffraction peak" means a diffraction peak with a half-width of less than 10°.

[0083] In contrast, in the production of biaxially stretched film, the film is stretched in a specific direction, and then stretched in a direction perpendicular to the first direction. Therefore, although the above-mentioned high-order structure is generated by the first stretching, the high-order structure is destroyed by the second stretching. Therefore, when in-plane measurements are performed on biaxially stretched film, the diffraction peaks in the resulting X-ray diffraction pattern are broad. In other words, when in-plane measurements are performed on biaxially stretched film, clear diffraction peaks do not appear.

[0084] As described above, the X-ray diffraction patterns obtained by in-plane measurement differ between uniaxially stretched films and biaxially stretched films. Therefore, it is possible to determine whether a stretched film is uniaxially stretched or biaxially stretched based on the in-plane measurement.

[0085] The thickness of the first intermediate layer 18 is preferably in the range of 10 to 100 μm, and more preferably in the range of 15 to 50 μm.

[0086] The first intermediate layer 18 may have a single-layer structure or a multi-layer structure. When the first intermediate layer 18 has a multi-layer structure, at least one layer of the first intermediate layer 18 may be a layer containing a petroleum-derived polyolefin or a layer containing a recycled polyolefin.

[0087] The first intermediate layer 18 may contain other resins as needed, as long as the petroleum-derived resin content in the self-standing packaging bag is 10% by volume or more or 10% by mass or more. The first intermediate layer 18 may be a layer formed by co-extrusion multilayer film formation of an ethylene-vinyl alcohol copolymer layer or a polyamide layer with an adhesive resin or the like, and then stretching the film. More specifically, examples include a three-type five-layer substrate consisting of petroleum-derived polyolefin / adhesive resin / ethylene-vinyl alcohol copolymer / adhesive resin / petroleum-derived polyolefin; a three-type three-layer substrate consisting of petroleum-derived polyolefin / adhesive resin / ethylene-vinyl alcohol copolymer; a multilayer substrate consisting of petroleum-derived (natural) polyolefin / recycled polyolefin / petroleum-derived (natural) polyolefin; petroleum-derived (natural) polyolefin / other polyolefin / recycled polyolefin / other polyolefin / petroleum-derived (natural) polyolefin; and the like. When the first intermediate layer 18 has a multilayer structure, the specific gravities of the same materials may differ depending on their functions.

[0088] The first intermediate layer 18 may be colored, for example, white.

[0089] The first intermediate layer 18 can be produced by known methods such as a casting method or an inflation method. Alternatively, a multilayer polyethylene film obtained by co-extruding polyethylenes of different densities can be used as the first intermediate layer 18. A stretched film can be obtained, for example, by stretching a film obtained by forming polyethylene into a film by a T-die method or an inflation method.

[0090] (1st inorganic compound layer) The first inorganic compound layer 15 is provided on one surface of the first intermediate layer 18. Here, the first inorganic compound layer 15 is provided on the surface of the first intermediate layer 18 facing the first sealant layer 12. The first inorganic compound layer may be provided on the surface of the first intermediate layer facing the first base material layer. The first inorganic compound layer may be provided on the surface of the first base material layer facing the first sealant layer. The first inorganic compound layer may be provided on the surface of the first base material layer opposite the first sealant layer. The main body film does not have to have a first inorganic compound layer.

[0091] The first inorganic compound layer 15 is a layer containing an inorganic compound. The first inorganic compound layer 15 may function as a gas barrier layer that suppresses the transmission of oxygen and water vapor. The first inorganic compound layer 15 may be formed by applying a coating liquid containing an inorganic compound, or by vapor-depositing an inorganic compound. The first inorganic compound layer 15 may be a metal thin film layer.

[0092] Examples of inorganic compounds contained in the first inorganic compound layer 15 include metals such as aluminum and silicon; and metal oxides such as aluminum oxide, silicon oxide, magnesium oxide, and tin oxide. The first inorganic compound layer 15 is preferably a vapor-deposited film made of a metal or a vapor-deposited film made of a metal oxide. From the viewpoints of light-blocking properties, gloss, and barrier properties, the metal is preferably aluminum. From the viewpoints of transparency and barrier properties, the metal oxide may be at least one selected from the group consisting of aluminum oxide, silicon oxide, and magnesium oxide. From the viewpoint of cost, the metal oxide is preferably at least one selected from the group consisting of aluminum oxide and silicon oxide. From the viewpoint of excellent tensile elongation during processing, the metal oxide is preferably silicon oxide. By forming the first inorganic compound layer 15 as a vapor-deposited film made of a metal or metal oxide, excellent barrier properties are achieved even in a very thin layer that does not affect the recyclability of the main film 111.

[0093] A vapor-deposited film made of a metal oxide has the advantage of being transparent, and therefore less likely to cause a user holding a packaging material made of a laminate to mistakenly believe that a metal foil is used, compared to a vapor-deposited film made of a metal.

[0094] The thickness of the aluminum vapor-deposited film is preferably 5 to 85 nm. A thickness of 5 nm or more can provide light-shielding properties, gloss, and barrier properties. Furthermore, a thickness of 85 nm or less can suppress the occurrence of cracks due to deformation caused by internal stress in the thin film, and can suppress a decrease in gas barrier properties. From the same viewpoint as above, the thickness of the aluminum vapor-deposited film is more preferably 40 to 80 nm.

[0095] The thickness of the vapor-deposited film made of aluminum oxide is preferably 5 to 30 nm. When the thickness is 5 nm or more, sufficient gas barrier properties can be obtained. Furthermore, when the thickness is 30 nm or less, the generation of cracks due to deformation caused by internal stress in the thin film can be suppressed, and deterioration of gas barrier properties can be suppressed. From the same viewpoint as above, the thickness of the vapor-deposited film made of aluminum oxide is more preferably 7 to 15 nm.

[0096] The thickness of the vapor-deposited film made of silicon oxide is preferably 10 to 50 nm. When the thickness is 10 nm or more, sufficient gas barrier properties can be obtained. Furthermore, when the thickness is 50 nm or less, the generation of cracks due to deformation caused by internal stress in the thin film can be suppressed, and deterioration of gas barrier properties can be suppressed. From the same viewpoint as above, the thickness of the vapor-deposited film made of silicon oxide is more preferably 20 to 40 nm.

[0097] The first inorganic compound layer 15 can be formed by, for example, vacuum film formation. For vacuum film formation, physical vapor deposition or chemical vapor deposition can be used. Examples of physical vapor deposition include vacuum deposition, sputtering, and ion plating. Examples of chemical vapor deposition include thermal CVD (Chemical Vapor Deposition), plasma CVD, and photo CVD.

[0098] In vacuum film formation, resistance heating vacuum deposition, EB (Electron Beam) heating vacuum deposition, induction heating vacuum deposition, sputtering, reactive sputtering, dual magnetron sputtering, and plasma enhanced chemical vapor deposition (PECVD) are particularly preferred. Vacuum deposition is preferred from the viewpoint of excellent productivity. As a heating means for vacuum deposition, it is preferred to use any one of electron beam heating, resistance heating, and induction heating.

[0099] A metal vapor-deposited layer made of aluminum is suitable for disposal. As long as the required light-blocking and barrier properties are satisfied, an aluminum vapor-deposited layer can be used instead of the first inorganic compound layer 15. The thickness of the aluminum vapor-deposited layer is preferably 40 to 80 nm. The aluminum vapor-deposited layer can be provided on the first intermediate layer 18, the first base layer 11, or the first sealant layer 12. When provided on the first sealant layer 12, the aluminum vapor-deposited layer preferably has a thickness of 30 to 50 nm, and when provided on the first intermediate layer 18 or the first base layer 11, the aluminum vapor-deposited layer preferably has a thickness of 40 to 80 nm.

[0100] (1st coating layer) The first coating layer 17 coats the first inorganic compound layer 15. The laminate of the first inorganic compound layer 15 and the first coating layer 17 constitutes a first gas barrier layer that improves the oxygen barrier property and water vapor barrier property of the main body film 111. The first gas barrier layer may include only the first inorganic compound layer 15, or may include only the first coating layer 17. The main body film does not necessarily have to have a first gas barrier layer.

[0101] The first coating layer 17 can be formed, for example, by applying a coating liquid. The coating liquid may contain a resin such as polyvinyl alcohol (PVA), ethylene-vinyl alcohol copolymer, ethylene-vinyl acetate copolymer, polyvinylidene chloride, polyacrylonitrile, or epoxy resin. The coating liquid may contain additives such as organic particles, inorganic particles, layered compounds, and curing agents.

[0102] The first coating layer 17 may be an organic-inorganic composite layer containing, for example, at least one selected from the group consisting of metal alkoxides, hydrolysates of metal alkoxides, and reaction products of metal alkoxide hydrolysates, and a water-soluble polymer. This organic-inorganic composite layer may further contain at least one selected from the group consisting of silane coupling agents, hydrolysates of silane coupling agents, silane coupling agents, and reaction products of hydrolysates of silane coupling agents.

[0103] Examples of metal alkoxides and their hydrolysates include compounds represented by the general formula M(OR), such as tetraethoxysilane [Si(OC2H5)4] and triisopropoxyaluminum [Al(OC3H7)3]. n The metal alkoxides and hydrolysates thereof may be used singly or in combination of two or more.

[0104] In terms of excellent oxygen barrier properties, the content of the metal alkoxide, its hydrolysate, and their reaction products in the coating liquid used to form the first coating layer 17 may be, for example, 40% by mass or more, 50% by mass or more, or 65% by mass or more. Furthermore, the total content of the metal alkoxide, its hydrolysate, and their reaction products in the coating liquid may be, for example, 70% by mass or less.

[0105] The water-soluble polymer contained in the first coating layer 17 is not particularly limited, and examples thereof include polyvinyl alcohol-based polymers, polysaccharides such as starch, methyl cellulose, and carboxymethyl cellulose, and hydroxyl group-containing polymers such as acrylic polyol-based polymers. From the viewpoint of further improving the oxygen gas barrier property, the water-soluble polymer preferably includes a polyvinyl alcohol-based water-soluble polymer. The number average molecular weight of the water-soluble polymer may be, for example, 40,000 to 180,000.

[0106] The polyvinyl alcohol-based water-soluble polymer contained in the first coating layer 17 can be obtained, for example, by saponifying (including partial saponification) polyvinyl acetate. This water-soluble polymer may have several tens of percent of acetate groups remaining, or may have only a few percent of acetate groups remaining.

[0107] The content of the water-soluble polymer in the coating liquid used to form the first coating layer 17 may be, for example, 15% by mass or more, or 20% by mass or more, based on the total mass of the organic-inorganic composite layer, from the viewpoint of excellent oxygen barrier properties. Also, the content of the water-soluble polymer in the coating liquid may be, for example, 50% by mass or less, or 45% by mass or less, from the viewpoint of excellent oxygen barrier properties.

[0108] Examples of the silane coupling agent used in the first coating layer 17 include silane coupling agents having an organic functional group. Examples of such silane coupling agents include ethyltrimethoxysilane, vinyltrimethoxysilane, γ-chloropropylmethyldimethoxysilane, γ-chloropropyltrimethoxysilane, glycidoxypropyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, and γ-methacryloxypropylmethyldimethoxysilane. The silane coupling agents, their hydrolysates, and their reaction products selected from these may be used alone or in combination of two or more.

[0109] It is preferable to use a silane coupling agent having an epoxy group as the organic functional group. Examples of silane coupling agents having an epoxy group include γ-glycidoxypropyltrimethoxysilane and β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane. The silane coupling agent having an epoxy group may have an organic functional group other than the epoxy group, such as a vinyl group, an amino group, a methacryl group, a ureyl group, or an isocyanate group. These may also be derivatized, multifunctionalized, or composited. One of the silane coupling agents selected from these, their hydrolyzates, and their reaction products may be used alone or in combination of two or more.

[0110] A silane coupling agent having an organic functional group, its hydrolyzate, or a reaction product thereof can further improve the oxygen barrier property of the first coating layer 17 and the adhesion to adjacent layers through the interaction between the organic functional group and the hydroxyl group of the water-soluble polymer. In particular, when the silane coupling agent, its hydrolyzate, or a reaction product thereof has an epoxy group and the water-soluble polymer is polyvinyl alcohol (PVA), the interaction between the epoxy group and the hydroxyl group of the PVA can further improve the oxygen barrier property and the adhesion to adjacent layers.

[0111] The total content of the silane coupling agent, its hydrolysate, and their reaction products in the coating liquid used to form the first coating layer 17 may be, for example, 1% by mass or more, or 2% by mass or more, based on the total mass of the organic-inorganic composite layer, from the viewpoint of excellent oxygen barrier properties. Also, the total content of the silane coupling agent, its hydrolysate, and their reaction products in the coating liquid may be, for example, 15% by mass or less, or 12% by mass or less, from the viewpoint of excellent oxygen barrier properties.

[0112] The thickness of the first coating layer 17 is preferably 50 to 1000 nm, and more preferably 100 to 500 nm. When the thickness of the first coating layer 17 is 50 nm or more, high gas barrier properties tend to be obtained, and when it is 1000 nm or less, sufficient flexibility tends to be maintained.

[0113] (First adhesive layer) The first adhesive layer 13A is provided between the first printed layer 14 and the first intermediate layer 18. The first adhesive layer 13B is provided between the first covering layer 17 and the first sealant layer 12. When the main body film does not have a first intermediate layer, the main body film may not have either the first adhesive layer 13A or 13B.

[0114] The first adhesive layers 13A and 13B are made of at least one type of adhesive. The adhesive may be a one-component curing adhesive, a two-component curing adhesive, or a non-curing adhesive. The adhesive may be a solventless adhesive or a solvent-based adhesive.

[0115] Examples of adhesives include epoxy adhesives such as polyether adhesives, polyester adhesives, silicone adhesives, and polyamine adhesives, as well as urethane adhesives, rubber adhesives, vinyl adhesives, silicone adhesives, epoxy adhesives, phenolic adhesives, and olefin adhesives. The adhesive may be an adhesive containing a biomass component. The adhesive is preferably a polyamine adhesive or urethane adhesive having gas barrier properties. Specific examples of gas barrier adhesives include "Maxieve" manufactured by Mitsubishi Gas Chemical Company, Inc. and "Paslim" manufactured by DIC Corporation.

[0116] The first adhesive layers 13A and 13B may be cured resin compositions containing polyester polyol and an isocyanate compound, or may be cured resin compositions containing a phosphoric acid-modified compound if necessary. Among the resin compositions used for the first adhesive layers 13A and 13B, for example, a polyol as the base agent and an isocyanate compound as the curing agent, or a polyamine resin as the base agent and an epoxy compound as the curing agent, it is preferable that either or both of the base agent and the curing agent have not only a linear structure but also a curved structure, or contain units capable of forming such a structure. For example, by incorporating a compound having a substituent at the ortho- or meta-position of an aromatic ring into these structures, it is possible to form not only linear crosslinks but also curved crosslinked structures in the cured coating. This curved crosslinked structure controls the molecular orientation, thereby contributing to oxygen barrier properties and water vapor barrier properties. The resin composition may also contain an inorganic compound, such as an inorganic layered compound, to further improve barrier properties. This can further improve the oxygen barrier properties and water vapor barrier properties of the main film 111.

[0117] The first adhesive layers 13A and 13B may be extruded or non-extruded resin layers. The first adhesive layers 13A and 13B may contain a heat-sealable adhesive thermoplastic resin. The adhesive thermoplastic resin may be any resin that can be melted and fused to each other by heat, such as low-density polyethylene, medium-density polyethylene, high-density polyethylene, linear low-density polyethylene, polypropylene, ethylene-propylene copolymer, methylpentene polymer, acid-modified polyolefin resins obtained by modifying polyolefin resins such as polyethylene or polypropylene with unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic acid, maleic anhydride, fumaric acid, itaconic acid, and the like.

[0118] The thickness of each of the first adhesive layers 13A and 13B is not particularly limited and may be, for example, 0.1 μm or more. By making the thickness of the adhesive layer 13A or more 1 μm, sufficient adhesive strength can be obtained. The thickness of the adhesive layer may be 2 μm or more. The thickness of the adhesive layer may be 50 μm or less, 5 μm or less, or 3 μm or less.

[0119] The first adhesive layers 13A, 13B can be formed by applying and drying onto the first intermediate layer 18 or the first sealant layer 12 using a conventionally known method such as direct gravure roll coating, gravure roll coating, kiss coating, reverse roll coating, Fontaine coating, or transfer roll coating.

[0120] (1st protective layer) The first protective layer 16 is the outermost layer of the main film 111, and covers the surface of the first base material layer 11 opposite to the first sealant layer 12. The main film does not necessarily have to have the first protective layer.

[0121] The first protective layer 16 may contain a cured product of a thermosetting resin. The thermosetting resin is not particularly limited as long as it produces a heat-resistant cured product, and examples thereof include polyurethane resin, polyester resin, polyamide resin, polyamideimide resin, acrylic resin, epoxy resin, and water-soluble polymer. The cured product of the thermosetting resin may be used alone or in combination of two or more. The first protective layer 16 may contain an inorganic filler, for example, from the viewpoint of improving heat resistance.

[0122] In one embodiment, the first protective layer 16 preferably contains a water-soluble polymer, and more preferably is an organic-inorganic composite layer that further contains an organometallic compound.

[0123] Examples of water-soluble polymers include polyvinyl alcohols, polysaccharides such as starch, methyl cellulose, and carboxymethyl cellulose, and hydroxyl group-containing polymers such as acrylic polyols. The first protective layer 16 preferably contains, for example, a polyvinyl alcohol-based hydroxyl group-containing polymer that the first coating layer 17 may contain.

[0124] The first protective layer 16 preferably contains at least one organic metal compound selected from the group consisting of metal alkoxides, hydrolyzates of metal alkoxides, metal alkoxides, and reaction products of hydrolyzates of metal alkoxides. Examples of metal alkoxides include those represented by the general formula M(OR), such as tetraethoxysilane [Si(OC2H5)4] and triisopropoxyaluminum [Al(OC3H7)3]. n Examples include those represented by the following formula:

[0125] It is preferable that the first protective layer 16 further contains, as an organometallic compound, at least one selected from the group consisting of a silane coupling agent, a hydrolysate of a silane coupling agent, and a reaction product of a silane coupling agent and a hydrolysate of a silane coupling agent.

[0126] The first protective layer 16 can be formed, for example, using a coating liquid for forming the first covering layer 17. When the main body film 111 has the first covering layer 17, the first protective layer 16 may be a layer formed using the same coating liquid as the coating liquid used to form the first covering layer 17. The first protective layer 16 is not limited to being formed by a method using a coating liquid, and can also be formed by co-extrusion of the polyethylene resin that constitutes the first base material layer 11 or the second base material layer 21 with a thermoplastic resin that has a high melting point and is heat resistant, such as a polyester resin, a polyamide resin, a polypropylene resin, or a polymethylpentene resin.

[0127] The first protective layer 16 reduces heat damage to the surface of the main body film 111 during heat sealing. By providing the main body film 111 with the first protective layer 16, which has excellent heat resistance, as the outermost layer, it is possible to ensure heat sealing properties and productivity even though the base material is polyethylene resin, which has poor heat resistance. The first protective layer 16 not only prevents defects during bag production by imparting heat resistance to the first base material layer 11, but is also expected to have the effect of preventing pinholes during transportation.

[0128] The thickness of the first protective layer 16 is preferably 0.3 to 3 μm. When the first protective layer 16 has a thickness of 0.3 μm or more, it tends to have sufficient heat resistance. When the first protective layer 16 has a thickness of 3 μm or less, it becomes easier to sufficiently dry the cured resin film during the manufacturing process of the main body film 111.

[0129] (other layers) The main body film 111 may further include other layers. For example, the main body film 111 may further include an anchor coat layer that coats the surface of the first intermediate layer 18 on which the first inorganic compound layer 15 is formed. The main body film 111 may further include an anchor coat layer that coats the surface of the first base material layer 11 on which the first inorganic compound layer 15 is formed. The main body film 111 may further include an anchor coat layer that coats the surface of the first intermediate layer 18 on which the first inorganic compound layer 15 is formed, and an anchor coat layer that coats the surface of the first base material layer 11 that faces the first adhesive layer 13A.

[0130] The anchor coat layer can be formed using a known anchor coat agent. This can improve adhesion between layers, for example, between the first intermediate layer 18 and the first inorganic compound layer 15. Examples of anchor coat agents include polyester-based polyurethane resins and polyether-based polyurethane resins. The anchor coat layer can also be a polyurethane-based cured coating obtained by reacting an isocyanate compound with various hydroxyl-containing polymers, such as polyester polyols, polyether polyols, and acrylic polyols. To improve adhesion between the substrate and the vapor-deposited layer, the anchor coat agent can contain the aforementioned silane coupling agent. From the standpoints of heat resistance and interlayer adhesive strength, the anchor coat agent is preferably a polyester-based polyurethane resin.

[0131] If the petroleum-derived resin content of the self-standing packaging bag is 10% by volume or more or 10% by mass or more, the main body film may further include a layer containing a resin other than polyolefin (non-polyolefin). Examples of non-polyolefin include polyamide resins such as nylon and polyester resins such as polyethylene terephthalate (PET).

[0132] When the main body film includes first base layer 11, first intermediate layer 18, and first sealant layer 12, first base layer 11 and first sealant layer 12 may contain petroleum-derived polyolefin, and first intermediate layer 18 may contain recycled polyolefin. In this case, even if first intermediate layer 18 contains impurities or foreign matter such as gel or aggregates, because first intermediate layer 18 is sandwiched between first base layer 11 and first sealant layer 12, the impurities or foreign matter such as gel or aggregates in first intermediate layer 18 are less likely to appear outside self-standing packaging pouch 110.

[0133] When the main body film includes the first base material layer 11 and the first sealant layer 12, at least one of the first base material layer 11 and the first sealant layer 12 may be a layer containing a petroleum-derived polyolefin.

[0134] <Bottom film> 5 is a cross-sectional view of the bottom film of the self-standing packaging pouch. The bottom film 112 includes, in this order, a second protective layer 26, a second base material layer 21, a second printed layer 24, a second adhesive layer 23A, a second intermediate layer 28, a second inorganic compound layer 25, a second coating layer 27, a second adhesive layer 23B, and a second sealant layer 22.

[0135] The bottom film 112 contains recycled polyolefin. Examples of polyolefin include polyethylene and polypropylene. Hereinafter, the polyolefin, polyethylene, polypropylene, etc. contained in each layer of the bottom film 112 may be recycled or not recycled.

[0136] The non-material recycled polyolefin may be a petroleum-derived polyolefin, a biomass-derived polyolefin, or a chemically recycled polyolefin. The pair of main film and bottom film may contain the same material or different materials.

[0137] The recycled polyolefin content in the bottom film 112 may be 10% by mass or more, preferably 20% by mass or more, more preferably 25% by mass or more, even more preferably 30% by mass or more, and particularly preferably 40% by mass or more, based on the total mass of the bottom film 112. The recycled polyolefin content in the bottom film 112 may be 10% by volume or more, based on the total volume of the bottom film 112, preferably 20% by volume or more, more preferably 25% by volume or more, even more preferably 30% by volume or more, and particularly preferably 40% or more.

[0138] The polyolefin content in the bottom film 112 is preferably 80% by volume or more or 80% by mass or more, more preferably 85% by volume or more or 85% by mass or more, and particularly preferably 90% by volume or more or 90% by mass or more, based on the total volume or total mass of the bottom film 112.

[0139] (2nd base layer) The second base material layer 21 may contain polyolefin, polyethylene, or polypropylene. Preferably, the second base material layer 21 is made of polyethylene and / or polypropylene. The second base material layer 21 may contain material-recycled polyolefin, or may contain non-material-recycled polyolefin.

[0140] The material used for the second base material layer 21 may be the same as that used for the first base material layer 11, except that the petroleum-derived resin of the first base material layer 11 is changed to a material recycled resin.

[0141] The second substrate layer 21 may be a non-stretched film or a stretched film. The second substrate layer 21 is preferably a stretched film. When the second substrate layer 21 is a stretched film, the second substrate layer 21 may be a uniaxially stretched film or a biaxially stretched film. When the second substrate layer 21 is a stretched film, the following effects are achieved. When the second substrate layer 21 is uniaxially stretched, it is possible to improve tearability, heat resistance, and the like. When the second substrate layer 21 is a biaxially stretched film, the mechanical strength and dimensional stability are improved, and printability is improved.

[0142] From the viewpoint of increasing the recycling rate and increasing the strength, the content of the material recycled polyolefin in the second base material layer 21 is preferably 10% by volume or more, 30% by volume or more, 50% by volume or more, or 80% by volume or more, based on the total volume of the second base material layer 21. According to one example, the second base material layer 21 is made of material recycled polyolefin. According to another example, the second base material layer 21 is made of material recycled polyolefin, non-material recycled polyolefin, and additives.

[0143] The second base material layer 21 may have the same structure as that described above for the first base material layer 11.

[0144] The second substrate layer 21 may further contain additives, similar to the first substrate layer 11. The second substrate layer 21 may be subjected to various pretreatments or provided with an anchor coat layer, similar to the first substrate layer 11. The thickness of the second substrate layer 21 may be within the same numerical range as the thickness of the first substrate layer 11.

[0145] (Second sealant layer) The second sealant layer 22 faces the second base layer 21. The second sealant layer 22 may contain a polyolefin, polyethylene, or polypropylene. Preferably, the first sealant layer 12 is made of polyethylene and / or polypropylene. The second sealant layer 22 may contain a material-recycled polyolefin, or a non-material-recycled polyolefin.

[0146] The material used for the second sealant layer 22 may be the same as that used for the first sealant layer 12, except that the petroleum-derived resin of the first sealant layer 12 is changed to a material recycled resin.

[0147] From the viewpoint of increasing the recycling rate and increasing the strength, the content of the material recycled polyolefin in the second sealant layer 22 is preferably 10% by volume or more, 30% by volume or more, 50% by volume or more, or 80% by volume or more, based on the total volume of the second sealant layer 22. According to one example, the second sealant layer 22 is made of material recycled polyolefin. According to another example, the second sealant layer 22 is made of material recycled polyolefin, non-material recycled polyolefin, and an additive.

[0148] The second sealant layer 22 preferably has a melting point lower than that of the second base material layer 21. In this case, when the laminate 20 is heat-sealed, it is possible to heat-seal the second sealant layer 22 while suppressing melting of the second base material layer 21.

[0149] The second sealant layer 22 may have a structure similar to that described above for the first sealant layer 12 .

[0150] The second sealant layer 22 may further contain additives, similar to the first sealant layer 12. The second sealant layer 22 may be subjected to various pretreatments or provided with an anchor coat layer, similar to the first sealant layer 12. The thickness of the second sealant layer 22 may be within the same numerical range as the thickness of the first sealant layer 12.

[0151] (2nd printing layer) The second printed layer 24 is provided on the surface of the second base layer 21 facing the second sealant layer 22. The position at which the second printed layer is provided on the bottom film is not limited. That is, the second printed layer 24 may be provided on the surface of the second base layer 21, or may be provided at any position between the second base layer 21 and the second sealant layer 22. For example, the second printed layer may be provided on either side of the second intermediate layer. Furthermore, the bottom film may include multiple second printed layers, or may not have a second printed layer.

[0152] The second printed layer 24 can be made of ink similar to that described above for the first printed layer 14. The second printed layer 24 can be formed by the same method as that described above for the first printed layer 14.

[0153] (Second middle class) The second intermediate layer 28 is provided between the second substrate layer 21 and the second sealant layer 22. Here, the second intermediate layer 28 is provided between the second substrate layer 21 and the second sealant layer 22 such that the second printed layer 24 is interposed between the second substrate layer 21 and the second intermediate layer 28. The bottom film does not necessarily have to have a second intermediate layer.

[0154] The second intermediate layer 28 may contain a polyolefin, polyethylene, or polypropylene. The polyolefin may be, for example, the same as the polyolefin contained in the first base material layer 11. The second intermediate layer 28 may further contain an additive that the first base material layer 11 may contain.

[0155] The second intermediate layer 28 may contain recycled material or may contain non-recycled polyolefin.

[0156] The material used for the second intermediate layer 28 may be the same as that used for the first intermediate layer 18, except that the petroleum-derived resin of the first intermediate layer 18 is changed to a material recycled resin.

[0157] In one example, the second intermediate layer 28 is made of a materially recycled polyolefin. In another example, the second intermediate layer 28 is made of a materially recycled polyolefin, a non-materially recycled polyolefin, and an additive.

[0158] The second intermediate layer 28 can have the same configuration as that described above for the first intermediate layer 18. The second intermediate layer 28 can be manufactured by the same method as that described above for the first intermediate layer 18.

[0159] The second intermediate layer 28 may further contain additives, similar to the first intermediate layer 18. The second intermediate layer 28 may be subjected to various pretreatments or provided with an anchor coat layer, similar to the first intermediate layer 18. The thickness of the second intermediate layer 28 may be within the same numerical range as the thickness of the first intermediate layer 18.

[0160] (Second inorganic compound layer) The second inorganic compound layer 25 is provided on one surface of the second intermediate layer 28. Here, the second inorganic compound layer 25 is provided on the surface of the second intermediate layer 28 facing the second sealant layer 22. The second inorganic compound layer may be provided on the surface of the second intermediate layer facing the second base material layer. The second inorganic compound layer may be provided on the surface of the second base material layer facing the second sealant layer. The second inorganic compound layer may be provided on the surface of the second base material layer opposite the second sealant layer. The bottom film may not have a second inorganic compound layer.

[0161] The second inorganic compound layer 25 may have the same structure as that described above for the first inorganic compound layer 15. The second inorganic compound layer 25 may be formed by the same method as that described above for the first inorganic compound layer 15.

[0162] The thickness of the second inorganic compound layer 25 may be within the same range as the numerical range of the thickness of the first inorganic compound layer 15 .

[0163] A metal vapor deposition layer made of aluminum is suitable for disposal. If the required light-blocking and barrier properties are satisfied, an aluminum vapor deposition layer can be used instead of the second inorganic compound layer 25. The thickness of the aluminum vapor deposition layer is preferably 40 to 80 nm. The aluminum vapor deposition layer can be provided on the second intermediate layer 28, the second base layer 21, or the second sealant layer 22. When provided on the second sealant layer 22, the aluminum vapor deposition layer preferably has a thickness of 30 to 50 nm, and when provided on the second intermediate layer 28 or the second base layer 21, the aluminum vapor deposition layer preferably has a thickness of 40 to 80 nm.

[0164] (2nd coating layer) The second coating layer 27 coats the second inorganic compound layer 25. A laminate of the second inorganic compound layer 25 and the second coating layer 27 constitutes a second gas barrier layer that improves the oxygen barrier property and water vapor barrier property of the bottom film 112. The second gas barrier layer may include only the second inorganic compound layer 25, or may include only the second coating layer 27. The bottom film 112 may not include the second gas barrier layer.

[0165] The second coating layer 27 may have the same structure as that described above for the first coating layer 17. The second coating layer 27 may be formed by the same method as that described above for the first coating layer 17.

[0166] The second coating layer 27 may further contain an additive, similar to the first coating layer 17. The thickness of the second coating layer 27 may be within the same numerical range as the thickness of the first coating layer 17.

[0167] (Second adhesive layer) The second adhesive layer 23A is provided between the second printed layer 24 and the second intermediate layer 28. The second adhesive layer 23B is provided between the second covering layer 27 and the second sealant layer 22. If the bottom film does not have a second intermediate layer, the bottom film may not have either the second adhesive layer 23A or 23B.

[0168] The second adhesive layers 23A and 23B are made of an adhesive similar to the configuration described above for the first adhesive layers 13A and 13B. The second adhesive layers 23A and 23B can have the same configuration as the configuration described above for the first adhesive layers 13A and 13B. The second adhesive layers 23A and 23B can be formed by the same method as the method described above for the first adhesive layers 13A and 13B.

[0169] The second adhesive layers 23A and 23B may further contain additives, similar to the first adhesive layers 13A and 13B. The thickness of the second adhesive layers 23A and 23B may be within the same numerical range as the thickness of the first adhesive layers 13A and 13B.

[0170] (2nd protective layer) The second protective layer 26 is a second protective layer. The second protective layer 26 is the outermost layer of the bottom film 112, and covers the back surface of the second base material layer 21 opposite the second sealant layer 22. The bottom film does not necessarily have to have a second protective layer.

[0171] The second protective layer 26 may have the same structure as that described above for the first protective layer 16. The second protective layer 26 may be formed by the same method as that described above for the first protective layer 16.

[0172] The second protective layer 26 may further contain an additive, similar to the first protective layer 16. The thickness of the second protective layer 26 may be within the same numerical range as the thickness of the first protective layer 16.

[0173] (other layers) The bottom film 112 may further include other layers. For example, the bottom film 112 may further include an anchor coat layer that coats the surface of the second intermediate layer 28 on which the second inorganic compound layer 25 is formed. The bottom film 112 may further include an anchor coat layer that coats the surface of the second base material layer 21 that faces the second adhesive layer 23A. The bottom film 112 may further include an anchor coat layer that coats the surface of the second intermediate layer 28 on which the first inorganic compound layer 15 is formed, and an anchor coat layer that coats the surface of the second base material layer 21 that faces the second adhesive layer 23A. The anchor coat layer can be formed using the anchor coat agent described above for the anchor coat layer of the main film 111.

[0174] The anchor coat layer of the bottom film 112 may further contain additives, similar to the anchor coat layer of the main film. The thickness of the anchor coat layer of the bottom film 112 may be within the same numerical range as the thickness of the anchor coat layer of the main film.

[0175] [Self-standing packaging bag, manufacturing method of packaged article] The self-standing packaging bag can be produced by folding a bottom film in half, sandwiching the folded bottom film between a pair of main body films, and heat-sealing them.

[0176] The bag making machine used to manufacture the self-standing packaging bag 110, for example, performs a heat-sealing process and a cutting process in this order. In the heat-sealing process, the bottom film 112, which has been folded in half as viewed from the second sealant layer 22 during the conveying process, is sandwiched between a pair of main films 111, which are conveyed so that the first sealant layers 12 face each other, and these are heat-sealed with a heat-sealing bar. Specifically, bottom sealing, point sealing, and side sealing are performed, thereby forming heat-sealed sections HS1, HS4, HS2A, and HS2B. The length direction of the heat-sealed section HS1 is perpendicular to the conveying direction. In the cutting process, the composite obtained by heat sealing is cut into individual self-standing packaging bags 110.

[0177] The packaged article 100 can be manufactured, for example, using a filling machine that performs a filling step and a heat-sealing step in this order. In the filling step, the self-standing packaging bag 110 is filled with the contents 120. In the heat-sealing step, the opening of the self-standing packaging bag 110 is heat-sealed with a heat-sealing bar to form a heat-sealed portion HS3. In this manner, the packaged article 100 can be manufactured. [Example]

[0178] The present invention will be described in more detail below using examples, but is not limited to these examples. Material recycling is abbreviated as "MR," chemical recycling as "CR," post-consumer recycling as "PCR," petroleum-derived as "NR," polyethylene as "PE," and polypropylene as "PP."

[0179] Example 1 A self-standing packaging bag was produced using a main body film having a thickness of 164 μm, a width of 0.16 m, and a length of 0.24 m and having the configuration shown in Table 1, and a bottom film having a thickness of 164 μm, a width of 0.16 m, and a folding width of 0.04 m and having the configuration shown in Table 1. The MR polyolefin content in the self-standing packaging bag was 2% by volume, the CR polyolefin content was 0% by volume, and the polyolefin content was 96% by volume.

[0180] Example 2 A self-standing packaging bag was produced using a main body film having a thickness of 107 μm, a width of 0.16 m, and a length of 0.24 m and having the configuration shown in Table 1, and a bottom film having a thickness of 107 μm, a width of 0.16 m, and a folding width of 0.04 m and having the configuration shown in Table 1. The MR polyolefin content in the self-standing packaging bag was 2% by volume, the CR polyolefin content was 0% by volume, and the polyolefin content was 93% by volume.

[0181] Example 3 A self-standing packaging bag was produced using a main body film having a thickness of 164 μm, a width of 0.16 m, and a length of 0.24 m and having the configuration shown in Table 1, and a bottom film having a thickness of 164 μm, a width of 0.16 m, and a folding width of 0.04 m and having the configuration shown in Table 1. The MR polyolefin content in the self-standing packaging bag was 2% by volume, the CR polyolefin content was 0% by volume, and the polyolefin content was 96% by volume.

[0182] Example 4 A self-standing packaging bag was produced using a main body film having a thickness of 107 μm, a width of 0.16 m, and a length of 0.24 m and having the configuration shown in Table 2, and a bottom film having a thickness of 107 μm, a width of 0.16 m, and a folding width of 0.04 m and having the configuration shown in Table 2. The MR polyolefin content in the self-standing packaging bag was 2% by volume, the CR polyolefin content was 0% by volume, and the polyolefin content was 93% by volume.

[0183] Example 5 A self-standing packaging bag was produced using a main body film having a thickness of 164 μm, a width of 0.16 m, and a length of 0.24 m and having the configuration shown in Table 2, and a bottom film having a thickness of 164 μm, a width of 0.16 m, and a folding width of 0.04 m and having the configuration shown in Table 2. The MR polyolefin content in the self-standing packaging bag was 4% by volume, the CR polyolefin content was 0% by volume, and the polyolefin content was 96% by volume.

[0184] Example 6 A self-standing packaging bag was produced using a main body film having a thickness of 107 μm, a width of 0.16 m, and a length of 0.24 m and having the configuration shown in Table 2, and a bottom film having a thickness of 107 μm, a width of 0.16 m, and a folding width of 0.04 m and having the configuration shown in Table 2. The MR polyolefin content in the self-standing packaging bag was 4% by volume, the CR polyolefin content was 0% by volume, and the polyolefin content was 93% by volume.

[0185] Example 7 A main body film having a thickness of 107 μm, a width of 0.16 m and a length of 0.24 m and having the configuration shown in Table 3, and a bottom film having a thickness of 107 μm, a width of 0.16 m and a folding width of 0.04 m and having the configuration shown in Table 3 were prepared, and a self-standing packaging bag was produced. The MR polyolefin content in the self-standing packaging bag was 8% by volume, the CR polyolefin content was 0% by volume, and the polyolefin content was 96% by volume.

[0186] Example 8 A self-standing packaging bag was produced using a main body film having a thickness of 107 μm, a width of 0.16 m, and a length of 0.24 m and having the configuration shown in Table 3, and a bottom film having a thickness of 107 μm, a width of 0.16 m, and a folding width of 0.04 m and having the configuration shown in Table 3. The MR polyolefin content in the self-standing packaging bag was 9% by volume, the CR polyolefin content was 0% by volume, and the polyolefin content was 94% by volume.

[0187] Example 9 A self-standing packaging bag was produced using a main body film having a thickness of 107 μm, a width of 0.16 m, and a length of 0.24 m and having the configuration shown in Table 3, and a bottom film having a thickness of 107 μm, a width of 0.16 m, and a folding width of 0.04 m and having the configuration shown in Table 3. The MR polyolefin content in the self-standing packaging bag was 3% by volume, the CR polyolefin content was 0% by volume, and the polyolefin content was 97% by volume.

[0188] Example 10 A main body film having a thickness of 164 μm, a width of 0.16 m, and a length of 0.24 m and having the configuration shown in Table 4, and a bottom film having a thickness of 164 μm, a width of 0.16 m, and a folding width of 0.04 m and having the configuration shown in Table 4 were prepared, and a self-standing packaging bag was produced. The MR polyolefin content in the self-standing packaging bag was 3% by volume, the CR polyolefin content was 0% by volume, and the polyolefin content was 95% by volume.

[0189] Example 11 A main body film having a thickness of 164 μm, a width of 0.16 m, and a length of 0.24 m and having the configuration shown in Table 4, and a bottom film having a thickness of 164 μm, a width of 0.16 m, and a folding width of 0.04 m and having the configuration shown in Table 4 were prepared, and a self-standing packaging bag was produced. The MR polyolefin content in the self-standing packaging bag was 11% by volume, the CR polyolefin content was 0% by volume, and the polyolefin content was 97% by volume.

[0190] Example 12 A main body film having a thickness of 164 μm, a width of 0.16 m, and a length of 0.24 m and having the configuration shown in Table 4, and a bottom film having a thickness of 164 μm, a width of 0.16 m, and a folding width of 0.04 m and having the configuration shown in Table 4 were prepared, and a self-standing packaging bag was produced. The MR polyolefin content in the self-standing packaging bag was 10% by volume, the CR polyolefin content was 0% by volume, and the polyolefin content was 95% by volume.

[0191] Example 13 A self-standing packaging bag was produced using a main body film having a thickness of 164 μm, a width of 0.16 m, and a length of 0.24 m and having the configuration shown in Table 5, and a bottom film having a thickness of 164 μm, a width of 0.16 m, and a folding width of 0.04 m and having the configuration shown in Table 5. The MR polyolefin content in the self-standing packaging bag was 14% by volume, the CR polyolefin content was 0% by volume, and the polyolefin content was 97% by volume.

[0192] Example 14 A main body film having a thickness of 164 μm, a width of 0.16 m, and a length of 0.24 m and having the configuration shown in Table 5, and a bottom film having a thickness of 164 μm, a width of 0.16 m, and a folding width of 0.04 m and having the configuration shown in Table 5 were prepared, and a self-standing packaging bag was produced. The MR polyolefin content in the self-standing packaging bag was 14% by volume, the CR polyolefin content was 0% by volume, and the polyolefin content was 95% by volume.

[0193] (Comparative Example 1) A self-standing packaging bag was produced using a main body film having a thickness of 164 μm, a width of 0.16 m, and a length of 0.24 m and having the configuration shown in Table 6, and a bottom film having a thickness of 164 μm, a width of 0.16 m, and a folding width of 0.04 m and having the configuration shown in Table 6. The MR polyolefin content in the self-standing packaging bag was 13% by volume, the CR polyolefin content was 0% by volume, and the polyolefin content was 96% by volume.

[0194] (Comparative Example 2) A main body film having a thickness of 107 μm, a width of 0.16 m, and a length of 0.24 m and having the configuration shown in Table 6, and a bottom film having a thickness of 107 μm, a width of 0.16 m, and a folding width of 0.04 m and having the configuration shown in Table 6 were prepared, and a self-standing packaging bag was produced. The MR polyolefin content in the self-standing packaging bag was 17% by volume, the CR polyolefin content was 0% by volume, and the polyolefin content was 93% by volume.

[0195] (Comparative Example 3) A self-standing packaging bag was produced using a main body film having a thickness of 164 μm, a width of 0.16 m, and a length of 0.24 m and having the configuration shown in Table 6, and a bottom film having a thickness of 164 μm, a width of 0.16 m, and a folding width of 0.04 m and having the configuration shown in Table 6. The MR polyolefin content in the self-standing packaging bag was 16% by volume, the CR polyolefin content was 0% by volume, and the polyolefin content was 96% by volume.

[0196] Comparative Example 4 A main body film having a thickness of 107 μm, a width of 0.16 m, and a length of 0.24 m and having the configuration shown in Table 7, and a bottom film having a thickness of 107 μm, a width of 0.16 m, and a folding width of 0.04 m and having the configuration shown in Table 7 were prepared, and a self-standing packaging bag was produced. The MR polyolefin content in the self-standing packaging bag was 17% by volume, the CR polyolefin content was 0% by volume, and the polyolefin content was 93% by volume.

[0197] (Comparative Example 5) A main body film having a thickness of 164 μm, a width of 0.16 m, and a length of 0.24 m and having the configuration shown in Table 7, and a bottom film having a thickness of 164 μm, a width of 0.16 m, and a folding width of 0.04 m and having the configuration shown in Table 7 were prepared, and a self-standing packaging bag was produced. The MR polyolefin content in the self-standing packaging bag was 30% by volume, the CR polyolefin content was 0% by volume, and the polyolefin content was 96% by volume.

[0198] (Comparative Example 6) A main body film having a thickness of 107 μm, a width of 0.16 m, and a length of 0.24 m and having the configuration shown in Table 7, and a bottom film having a thickness of 107 μm, a width of 0.16 m, and a folding width of 0.04 m and having the configuration shown in Table 7 were prepared, and a self-standing packaging bag was produced. The MR polyolefin content in the self-standing packaging bag was 28% by volume, the CR polyolefin content was 0% by volume, and the polyolefin content was 93% by volume.

[0199] (Comparative Example 7) A main body film having a thickness of 164 μm, a width of 0.16 m, and a length of 0.24 m and having the configuration shown in Table 8, and a bottom film having a thickness of 164 μm, a width of 0.16 m, and a folding width of 0.04 m and having the configuration shown in Table 8 were prepared, and a self-standing packaging bag was produced. The MR polyolefin content in the self-standing packaging bag was 19% by volume, the CR polyolefin content was 0% by volume, and the polyolefin content was 97% by volume.

[0200] (Comparative Example 8) A main body film having a thickness of 164 μm, a width of 0.16 m, and a length of 0.24 m and having the configuration shown in Table 8, and a bottom film having a thickness of 164 μm, a width of 0.16 m, and a folding width of 0.04 m and having the configuration shown in Table 8 were prepared, and a self-standing packaging bag was produced. The MR polyolefin content in the self-standing packaging bag was 24% by volume, the CR polyolefin content was 0% by volume, and the polyolefin content was 95% by volume.

[0201] (Comparative Example 9) A main body film having a thickness of 164 μm, a width of 0.16 m, and a length of 0.24 m and having the configuration shown in Table 9, and a bottom film having a thickness of 164 μm, a width of 0.16 m, and a folding width of 0.04 m and having the configuration shown in Table 9 were prepared, and a self-standing packaging bag was produced. The MR polyolefin content in the self-standing packaging bag was 78% by volume, the CR polyolefin content was 0% by volume, and the polyolefin content was 97% by volume.

[0202] (Comparative Example 10) A main body film having a thickness of 164 μm, a width of 0.16 m, and a length of 0.24 m and having the configuration shown in Table 9, and a bottom film having a thickness of 164 μm, a width of 0.16 m, and a folding width of 0.04 m and having the configuration shown in Table 9 were prepared, and a self-standing packaging bag was produced. The MR polyolefin content in the self-standing packaging bag was 72% by volume, the CR polyolefin content was 0% by volume, and the polyolefin content was 95% by volume.

[0203] [Table 1]

[0204] [Table 2]

[0205] [Table 3]

[0206] [Table 4]

[0207] [Table 5]

[0208] [Table 6]

[0209] [Table 7]

[0210] [Table 8]

[0211] [Table 9]

[0212] [evaluation] (Hygiene) The self-standing packaging pouches were analyzed using purge-and-trap gas chromatography / mass spectrometry. Specifically, 1.2 g samples were cut from the main film of the self-standing packaging pouch and 0.2 g samples from the bottom film. These samples were placed in a 20 mL vial along with an odor component collector and heated at 60°C for 1 hour to adsorb the volatile components from the sample onto the collector. The volatile components in the collector were analyzed using a purge-and-trap gas chromatography / mass spectrometry system to obtain a total ion chromatogram. Next, the ratio (R1) of the peak area of ​​nonanal to the sum of the peak areas of all aliphatic hydrocarbon components, and the ratio (R2) of the peak area of ​​decanal to the sum of the peak areas of all aliphatic hydrocarbon components, both of which serve as indicators of odor components, were calculated. Evaluation was then performed based on the following criteria. The evaluation results are shown in Table 10. (Evaluation criteria) A: R1 is less than 1.5% and R2 is less than 0.35%. B: R1 is less than 1.5% and R2 is 0.35% or more, or R1 is 1.5% or more and R2 is less than 0.35%. C: R1 is 1.5% or more and R2 is 0.35% or more.

[0213] (strength) A self-standing packaging bag was filled with 800 ml of 5°C cold water to obtain a package. The obtained package was allowed to drop freely from a height of 120 cm 10 times to check for breakage. Thirty bags were used as samples for each Example, Comparative Example, and Reference Example. The self-standing packaging bag's performance was evaluated based on the number of breakages using the following evaluation criteria. The evaluation results are shown in Table 10. (Evaluation criteria) A: None of the 30 bags were broken. B: 1 to 3 or more bags out of 30 bags were broken. C: Four or more bags out of 30 were broken.

[0214] (Foreign object) Samples of 240mm x 160mm x 2 sheets (front and back) x 10 bags were cut out from the main film of 10 self-standing packaging bags, and 40mm x 160mm x 2 sheets (front and back) x 10 bags were cut out from the bottom film. The samples were placed on a black table, and protrusions (protruding foreign matter) with a diameter of 0.5mm or more but less than 1mm were counted visually as fisheye 1 (N1), and protrusions (protruding foreign matter) with a diameter of 1mm or more were counted visually as fisheye 2 (N2), and evaluation was performed based on the following evaluation criteria. The evaluation results are shown in Table 10. (Evaluation criteria) A: N1 is 10 or less and N2 is 0. B: N1 is 11 to 99 and N2 is 0. C: N1 is 100 or more or N2 is 1 or more.

[0215] [Table 10] [Explanation of symbols]

[0216] 11...first base material layer, 12...first sealant layer, 13A, 13B...first adhesive layer, 14...first printed layer, 15...first inorganic compound layer, 16...first protective layer, 17...first coating layer, 18...first intermediate layer, 21...second base material layer, 22...second sealant layer, 23A...second adhesive layer, 23B...second adhesive layer, 24...second printed layer, 25...second inorganic compound layer, 26...second protective layer, 27...second coating layer, 28...second intermediate layer, 100...packaged article, 100A...packaged article, 110...self-standing packaging bag, 111, 111A, 111B...main body film, 112...bottom film, 113...spout, 114...cap, 120...contents, HS1, HS2A, HS2B, HS3, HS4...heat seal portion, MF...mountain fold portion.

Claims

1. A self-standing packaging bag comprising a pair of opposing main film layers and a bottom film, and containing polyolefin, Each of the pair of main films contains a petroleum-derived polyolefin, The self-standing packaging bag, wherein the bottom film contains recycled polyolefin.

2. Each of the pair of main films has a first base material layer, a first intermediate layer, and a first sealant layer, The self-standing packaging bag according to claim 1 , wherein the first substrate layer contains the petroleum-derived polyolefin.

3. Each of the pair of main films has a first base material layer, a first intermediate layer, and a first sealant layer, The self-standing packaging bag according to claim 1 , wherein the first intermediate layer contains the petroleum-derived polyolefin.

4. Each of the pair of main films has a first base material layer, a first intermediate layer, and a first sealant layer, The self-standing packaging bag according to claim 1 , wherein the first sealant layer contains the petroleum-derived polyolefin.

5. the bottom film has a second substrate layer, a second intermediate layer, and a second sealant layer; The self-standing packaging bag according to claim 1 , wherein the second base layer contains the recycled polyolefin.

6. the bottom film has a second substrate layer, a second intermediate layer, and a second sealant layer; The self-standing packaging bag according to claim 1 , wherein the second intermediate layer contains the recycled polyolefin.

7. the bottom film has a second substrate layer, a second intermediate layer, and a second sealant layer; The self-standing packaging bag according to claim 1 , wherein the second sealant layer contains the recycled polyolefin.

8. 2. The self-standing packaging bag according to claim 1, wherein the content of the material recycled polyolefin is 1% by volume or more based on the total volume of the self-standing packaging bag.

9. 2. The self-standing packaging bag according to claim 1, wherein the content of the material recycled polyolefin is 1% by mass or more based on the total mass of the self-standing packaging bag.

10. 2. The self-standing packaging bag according to claim 1, wherein the content of the material recycled polyolefin is 5% by volume or more based on the total volume of the self-standing packaging bag.

11. 2. The self-standing packaging bag according to claim 1, wherein the content of the material recycled polyolefin is 5% by mass or more based on the total mass of the self-standing packaging bag.

12. 2. The self-supporting packaging bag according to claim 1, wherein the polyolefin is a post-consumer recycled polyolefin.

13. 2. The self-standing packaging bag according to claim 1, wherein the content of the polyolefin is 80% by volume or more based on the total volume of the self-standing packaging bag.

14. The self-standing packaging bag according to claim 1, wherein the content of the polyolefin is 80% by mass or more based on the total mass of the self-standing packaging bag.

15. The self-standing packaging bag according to claim 1 , wherein the pair of main body films and the bottom film contain the same material.

16. The self-standing packaging bag according to claim 1 , wherein the bottom film contains at least one of a petroleum-derived polyolefin and a biomass-derived polyolefin.

17. The pair of main body films and the bottom film each have a multi-layer structure, The self-standing packaging bag according to claim 1, wherein the innermost layer of the multilayer structure is made of at least one of a petroleum-derived polyolefin and a biomass-derived polyolefin.

18. The self-standing packaging bag according to any one of claims 2 to 4, further comprising a gas barrier layer between the first base material layer and the first sealant layer.

19. The self-standing packaging bag according to any one of claims 5 to 7, further comprising a gas barrier layer between the second base material layer and the second sealant layer.

20. The self-standing packaging bag according to any one of claims 1 to 17, Contents contained in the self-standing packaging bag; A packaging article comprising:

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