Laminated body and packaging bag using the same

Abstract

To provide a laminate excellent in bag-making aptitude and dead holding ability, even using biomass polyethylene and also to provide a packaging bag using the same.SOLUTION: A laminate 10 is a laminate in which a sealant layer 12 is formed on a base material layer directly or via an anchor coat layer. A basis weight P of the paper base layer 11 is 20 g / m2 or more and 99 g / m2 or less; the sealant layer 12 contains a biomass polyethylene that is a polymer made from a monomer containing a biomass-derived ethylene, and has a biomass content of 5% or more; the sealant layer 12 includes, in order from the base material layer side, a layer of the biomass polyethylene and a layer of fossil fuel-derived polyethylene; the sealant layer 12 has a thickness S1 of 20 μm or more to 60 μm or less; and a basis weight P of the paper base layer 11, a thickness S1 of the sealant layer 12, and a density M1 of the sealant layer 12 satisfy a following condition: 0.33<(S1×M1) / P<1.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a laminate including a paper base material and a sealant layer, and a packaging bag using the same.

Background Art

[0002] Conventionally, in paper containers such as paper cups and trays, a laminate having a paper base material layer / sealant layer structure is known. Further, by replacing at least a part of the sealant layer with a polymer of a monomer containing ethylene derived from biomass, which is a biomass polyethylene, reduction of the use of fossil fuels as a packaging material has been studied (for example, see Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, unlike containers such as paper cups, in a so-called paper flexible packaging material composed of a paper base material layer having a low basis weight and a sealant layer and having flexibility, there are problems such as a decrease in bag-making suitability due to poor filling of the seal portion and insufficient dead-hold property.

[0005] An object of the present invention is to provide a laminate excellent in bag-making suitability and dead-hold property while using biomass polyethylene in order to solve the above problems, and a packaging bag using the same.

Means for Solving the Problems

[0006] The present invention solves the above problems by the following means. For ease of understanding, the description will be given with reference numerals corresponding to the embodiments of the present invention, but the present invention is not limited thereto.

[0007] A first invention is a laminate (10) in which a sealant layer (12) is formed directly or via an anchor coat layer on a base material layer including at least a paper base material layer (11), wherein the paper base material layer has a basis weight P of 20 g / m 2 or more and 99 g / m 2 or less, the sealant layer contains biomass polyethylene which is a polymer of a monomer containing ethylene derived from biomass, and has a biomass content of 5% or more, the sealant layer has, in order from the base material layer side, a layer of biomass polyethylene and a layer of polyethylene derived from fossil fuel, the sealant layer has a thickness S1 of 20 μm or more and 60 μm or less, and the laminate satisfies the following relational expression (I) for the basis weight P of the paper base material layer, the thickness S1 of the sealant layer, and the density M1 of the sealant layer. 0.33 < (S1 × M1) / P < 1 ··· (I)

[0008] A second invention is a laminate (10A) in which an adhesive resin layer or an adhesive layer (15) and a sealant layer (12A) are sequentially formed directly or via an anchor coat layer on a base material layer (11) including at least a paper base material layer, wherein the paper base material layer has a basis weight P of 20 g / m 2 or more and 99 g / m 2 or less, the sealant layer and / or the adhesive resin layer contains biomass polyethylene which is a polymer of a monomer containing ethylene derived from biomass, and the biomass content of the sealant layer and the adhesive resin layer is 5% or more, the sealant layer has, in order from the base material layer side, a layer of biomass polyethylene and a layer of polyethylene derived from fossil fuel, The total thickness S4 of the thickness S2 of the sealant layer and the thickness S3 of the adhesive resin layer is 20 μm or more and 60 μm or less, The laminate is such that the basis weight P of the paper base material layer, the thickness S2 of the sealant layer, the density M2 of the sealant layer, the thickness S3 of the adhesive resin layer, and the density M3 of the adhesive resin layer satisfy the following relational expression (II). 0.33 < (S2 × M2 + S3 × M3) / P < 1 ···(II)

[0009] A third invention is a pillow packaging bag (50) formed using the laminate of the first invention or the second invention.

[0010] A fourth invention is a gusset packaging bag (70) formed using the laminate of the first invention or the second invention.

[0011] A fifth invention is a packaging bag according to the third invention or the fourth invention, wherein the content accommodated in the packaging bag is powder or granules.

Advantages of the Invention

[0012] According to the present invention, it is possible to provide a laminate excellent in bag-making suitability and dead-holding property while using biomass polyethylene, and a packaging bag using the same.

Brief Description of the Drawings

[0013]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Embodiments for Carrying Out the Invention

[0014] The laminate according to the present invention will be described with reference to the drawings. Examples of cross-sectional views of the laminate according to the present invention are shown in Figs. 1 and 2. <Laminate of the First Embodiment> As shown in Fig. 1, in the laminate 10 of the first embodiment which is an example of the first invention of the present invention, a sealant layer 12 is directly formed on a base material layer including a paper base material layer 11 without an adhesive resin layer or an adhesive layer interposed therebetween. This embodiment has a laminated structure in which the sealant layer 12 is formed by a conventionally known extrusion coating method, and the sealant layer 12 is formed by melt extrusion on the paper base material layer 11. Also, a pattern layer 13 and a surface layer 14 are sequentially formed on the surface of the paper base material layer 11 opposite to the sealant layer 12. Hereinafter, each layer constituting the laminate 10 will be described.

[0015] (Paper Base Material Layer) The paper base material layer 11 is a base material layer that supports the sealant layer 12, and is different from cup base paper for paper cups with a basis weight of 100 g / m 2 or more, and milk carton base paper for paper containers. It is a paper base material that constitutes a flexible, so-called paper soft package. Specifically, the basis weight P of the paper base material is 20 g / m 2 or more and 99 g / m 2 or less, preferably 30 g / m 2 or more and 80 g / m 2 or less. When the basis weight P of the paper base material is 20 g / m 2 or more and 99 g / m 2 or less, it has strong mechanical strength, has a predetermined dead-hold property, and has flexibility as a packaging bag. Examples of the paper base material layer include kraft paper, fine paper, coated paper, vapor-deposited paper, and paper with barrier properties (barrier paper).

[0016] <Barrier Paper> Here, as the paper with barrier properties (barrier paper), for example, Shield Plus manufactured by Nippon Paper Industries Co., Ltd. can be applied. The barrier paper has one or more barrier layers formed on a paper base material such as the above-mentioned kraft paper, fine paper, coated paper, etc., and preferably, a water vapor barrier layer and a gas barrier layer are provided in this order. It is preferable that the water vapor barrier layer and the gas barrier layer are each formed by applying and drying an aqueous composition. A polymer binder, pigments, crosslinking agents, etc. may be added mainly to the composition of each layer.

[0017] <<Polymer binder>> As the polymer used as the main component of the composition constituting the water vapor barrier layer and the gas barrier layer of the barrier paper, a resin that can use water as a dispersion medium is suitable. The composition includes a form of a polymer aqueous solution or an emulsion. This polymer corresponds to a binder.

[0018] <<Water vapor barrier layer>> As the resin to be contained in the water vapor barrier layer, various copolymers such as styrene-butadiene-based, styrene-acrylic-based, ethylene-vinyl acetate-based, butadiene-methyl methacrylate-based, vinyl acetate-butyl acrylate-based, maleic anhydride copolymer, acrylic acid-methyl methacrylate-based copolymer, etc. can be used alone or in a mixture of two or more.

[0019] It is preferable to contain a pigment in the water vapor barrier layer from the viewpoint of improving the water vapor barrier property and also improving the adhesion between the water vapor barrier layer and the gas barrier layer. As the pigment to be contained in the water vapor barrier layer, inorganic pigments and organic pigments can be used. Inorganic pigments are preferred. Examples of inorganic pigments include kaolin, clay, calcium carbonate, talc, titanium dioxide, barium sulfate, calcium sulfate, zinc oxide, silicic acid, silicate, colloidal silica, satin white. Pigments with a flat shape are suitable. Among these pigments, inorganic pigments such as kaolin with a flat shape can improve the barrier property against water vapor. In particular, kaolin with an average particle diameter of 5 μm or more and an aspect ratio of 10 or more is more suitable. When the flat pigments are distributed parallel to the coating layer, the water vapor that has penetrated into the water vapor barrier layer is blocked from moving in the thickness direction by the flat pigments and instead moves circuitously. As a result, the path for the water vapor to pass through the water vapor barrier layer becomes longer, and the barrier property can be improved. When the aspect ratio of the added pigment is small, the number of times the water vapor detours in the coating layer decreases and the moving distance becomes shorter. As a result, the water vapor barrier property is lower than that of flat pigments with a large particle diameter. In addition to kaolin, mica and montmorillonite can also be used as flat pigments.

[0020] From the viewpoints of improving the water vapor barrier property and the adhesion to the gas barrier layer, it is preferable to further contain a pigment with an average particle diameter of 5 μm or less in the water vapor barrier layer containing kaolin with an average particle diameter of 5 μm or more and an aspect ratio of 10 or more. A structure is formed in which the pigment with an average particle diameter of 5 μm or less penetrates between the kaolins with an average particle diameter of 5 μm or more and an aspect ratio of 10 or more that exist in a multilayered manner. The water vapor that is forced to move along the surface of the flat kaolin is blocked from moving by these small pigment particles. That is, when the water vapor barrier layer contains pigments with different flatness and average particle diameters, in the water vapor barrier layer, the voids formed between adjacent flat pigments with a large particle diameter are filled with pigments with a small particle diameter. Therefore, the water vapor passes through by detouring around the pigments, and a higher water vapor barrier property can be realized compared to a water vapor barrier layer that does not contain pigments with a small particle diameter. It is preferable that the blending ratio of kaolin having an average particle diameter of 5 μm or more and an aspect ratio of 10 or more and a pigment having an average particle diameter of 5 μm or less is 50 / 50 to 99 / 1 by dry weight. If the ratio of kaolin having an average particle diameter of 5 μm or more and an aspect ratio of 10 or more is less than the above range, the distance that water vapor bypasses in the coating layer becomes short, and sufficient water vapor barrier properties cannot be obtained, which is not preferable. On the other hand, if it is more than the above range, the voids formed by the large-particle-size pigments in the coating layer cannot be sufficiently filled with pigments having an average particle diameter of 5 μm or less, and thus no improvement in water vapor barrier properties is seen, which is not preferable.

[0021] Examples of the pigment having an average particle diameter of 5 μm or less include inorganic pigments such as kaolin, clay, calcium carbonate, calcium carbonate, talc, titanium dioxide, barium sulfate, calcium sulfate, zinc oxide, silicic acid, silicate, colloidal silica, satin white, and organic pigments, which can be used alone or in a mixture of two or more. Among these pigments, calcium carbonate, especially heavy calcium carbonate, is preferable. When the pigment is contained in the water vapor barrier layer, the blending amount of the resin and the pigment is preferably in the range of 5 to 200 parts by weight of the resin (dry weight) with respect to 100 parts by weight of the pigment (dry weight), and more preferably 20 to 150 parts by weight of the resin. In addition to the resin and the pigment, various commonly used auxiliary agents such as a dispersant, a thickener, a water retention agent, an antifoaming agent, a waterproofing agent, a dye, and a fluorescent dye can be used in the water vapor barrier layer.

[0022] The crosslinking agent causes a crosslinking reaction with the binder contained in the water vapor barrier layer, so that the number of bonds (crosslinking points) in the water vapor barrier layer increases. That is, the water vapor barrier layer has a dense structure and can exhibit good water vapor barrier properties. The crosslinking agent to be incorporated into the water vapor barrier layer is not particularly limited, and can be appropriately selected from polyvalent metal salts (compounds formed by the combination of polyvalent metals such as copper, zinc, silver, iron, potassium, sodium, zirconium, aluminum, calcium, barium, magnesium, titanium, etc. and ionic substances such as carbonate ions, sulfate ions, nitrate ions, phosphate ions, silicate ions, nitrogen oxides, boron oxides, etc.), amine compounds, amide compounds, aldehyde compounds, hydroxy acids, etc. according to the type of binder contained in the water vapor barrier layer. The compounding ratio of the crosslinking agent can be compounded without particular limitation as long as it is within the range of the paint concentration and paint viscosity that can be applied. When using styrene-based water vapor barrier resins such as styrene-butadiene-based and styrene-acrylic-based resins that exhibit excellent water vapor barrier properties, from the viewpoint of expressing the crosslinking effect, it is preferable to use a polyvalent metal salt, and more preferably potassium alum. The addition amount of the crosslinking agent is preferably 1 to 10 parts by weight, more preferably 3 to 5 parts by weight, based on 100 parts by weight of the binder resin used in the water vapor barrier layer. If it is less than 1 part by weight, a sufficient effect cannot be achieved, and if it is more than 10 parts by weight, the viscosity of the coating liquid increases significantly, making it difficult to apply.

[0023] <<Gas barrier layer>> As the water-soluble polymer used as the binder resin of the coating material for forming the gas barrier layer, fully saponified polyvinyl alcohol, partially saponified polyvinyl alcohol, ethylene copolymerized polyvinyl alcohol, polyvinyl pyrrolidone, starch, methyl cellulose, carboxymethyl cellulose, sodium alginate, etc. can be used. Among these, from the viewpoint of gas barrier properties, polyvinyl alcohol and carboxymethyl cellulose are preferable, and polyvinyl alcohol is more preferable. Note that "gas barrier" means gas barrier property and includes oxygen barrier property.

[0024] As the pigment used in the gas barrier layer, the same pigments as those used in the above-mentioned water vapor barrier layer can be used. It is more preferable to use inorganic pigments (especially kaolin) having an average particle diameter of 3 μm or more and an aspect ratio of 10 or more, and it is particularly preferable to use inorganic pigments (especially kaolin) having an average particle diameter of 5 μm or more and an aspect ratio of 50 or more. When the gas barrier layer contains a pigment, gases such as oxygen pass around the pigment, so that compared with the gas barrier layer not containing the pigment, good gas barrier properties, especially excellent gas barrier properties in a high humidity atmosphere, can be realized. The blending ratio (dry weight) of the pigment and the water-soluble polymer contained in the gas barrier layer is preferably such that the pigment / water-soluble polymer is 1 / 100 to 1000 / 100. When the ratio of the pigment is outside the above range, sufficient gas barrier properties may not be exhibited.

[0025] Regarding the crosslinking agent, the same crosslinking agent as that used in the above-mentioned water vapor barrier layer can be used. In order to bond the hydroxyl groups of the water-soluble polymer to each other in a crosslinked structure, the amount of hydroxyl groups that loosen (or break) the bond when the humidity becomes high decreases, and the water resistance of the entire layer is improved, so it is possible to suppress the decrease in oxygen barrier properties under high humidity. The addition amount of the crosslinking agent is preferably 1 to 10 parts by weight, more preferably 3 to 5 parts by weight, based on 100 parts by weight of the resin used in the gas barrier layer. When it is less than 1 part by weight, a sufficient effect cannot be obtained, and when it is more than 10 parts by weight, the viscosity of the composition increases significantly, making coating difficult.

[0026] In addition to the water-soluble polymer, pigment, and crosslinking agent, various commonly used auxiliaries such as a dispersant, thickener, water retention agent, defoaming agent, water resistance agent, dye, and fluorescent dye can be used in the gas barrier layer.

[0027] (Base material layer) In the present invention, the base material layer includes a paper base material layer. The base material layer may be composed of a plurality of layers further including layers other than paper. For example, from the outermost layer side, a multi-layer structure including a barrier film such as aluminum foil, aluminum vapor-deposited film, or transparent vapor-deposited film as a barrier layer, such as paper / second bonding layer / barrier layer ( " / " means lamination), is also the base material layer in the present invention. That is, the structure before the sealant layer is extrusion-coated is the base material layer in the present invention. Note that, as the above-mentioned second bonding layer, polyethylene or the like can be exemplified, and it may contain biomass polyethylene described later. Further, not only polysand lamination by the second bonding layer but also lamination by a dry lamination method via an adhesive may be employed. Also, from the viewpoint of improving the adhesion of the sealant layer 12 to the base material layer, an anchor coat layer may be provided on the surface of the base material layer where the sealant layer is formed, so that the base material layer, the anchor coat layer, and the sealant layer are laminated in this order. Here, as the material used for the anchor coat layer, for example, urethane-based resins, epoxy-based resins, polyolefin resins, etc. can be used. The thickness of the anchor coat layer is preferably formed, for example, to be 0.1 μm or more and 1.0 μm or less. Also, when the sealant layer 12 is directly provided on the paper base material layer of the base material layer without providing an anchor coat layer, corona treatment may be performed on the surface of the paper base material layer on the side where the sealant layer is formed to improve the adhesion of the sealant layer 12 to the paper base material layer.

[0028] (Sealant layer) The sealant layer 12 is the innermost layer when a packaging bag is formed using the laminate. The sealant layer 12 contains biomass polyethylene, whereby the amount of fossil fuel used can be reduced and the environmental load can be decreased. Further, the laminate according to the present invention is not inferior in terms of physical properties such as mechanical properties compared to a sealant layer of polyethylene produced from raw materials obtained from conventional fossil fuels, and thus can replace a laminate of a conventional polyolefin resin. In the present invention, "biomass polyethylene" means a material using at least partially biomass-derived (plant-derived) raw materials as raw materials, and it is not necessary for all of the raw materials to be biomass-derived.

[0029] The sealant layer 12 may be a single layer or may be co-extruded in two or more layers. In the case of a single layer, it may be composed of biomass polyethylene alone or may be blended with fossil fuel-derived polyethylene. In the case of a co-extruded structure of two or more layers, it is not necessarily the case that there is a layer of biomass polyethylene in the innermost layer. For example, from the side of the outermost base material layer, a structure of biomass polyethylene / fossil fuel-derived polyethylene may be used. Examples of other resins derived from fossil fuels include LDPE (low density polyethylene), LLDPE (linear low density polyethylene), MDPE (medium density polyethylene), and HDPE (high density polyethylene). These may be blended with biomass polyethylene or may be used as a co-extruded layer as described above.

[0030] The thickness S1 of the sealant layer 12 is 20 μm or more and 60 μm or less. As described above, when the sealant layer 12 is composed of multiple layers, it means the total thickness thereof. When the thickness S1 is 20 μm or more and 60 μm or less, sufficient seal strength can be obtained, the seal part is sufficiently filled when forming a packaging bag, and further, it has appropriate dead hold properties when laminated with paper. Further, if it is 20 μm or more and 40 μm or less, it is further excellent in cuttability (openability) when laminated with paper.

[0031] (biomass polyethylene) The sealant layer 12 contains biomass polyethylene, which is a polymer of monomers containing ethylene derived from biomass, and has a biomass content of 5% or more. The sealant layer 12 may further contain polyolefins derived from fossil fuels and the like.

[0032] The "biomass content" (the concentration of carbon derived from biomass in biomass polyethylene) is a value obtained by measuring the content of carbon derived from biomass by radiocarbon (C14) measurement. Since carbon dioxide in the atmosphere contains C14 at a certain ratio (105.5 pMC), it is known that the C14 content in plants that grow by taking in carbon dioxide in the atmosphere, such as corn, is also about 105.5 pMC. It is also known that fossil fuels contain almost no C14. Therefore, by measuring the ratio of C14 contained in all carbon atoms in the sealant layer 12, the ratio of carbon derived from biomass can be calculated. In the present invention, when the C14 content in the sealant layer 12 is PC14, the content of carbon derived from biomass, Pbio, can be obtained as follows. Pbio (%) = PC14 / 105.5 × 100

[0033] Theoretically, if ethylene derived entirely from biomass is used as the raw material for the sealant layer 12, the biomass content is 100%, and the biomass content of the sealant layer 12 is 100%. Also, the concentration of carbon derived from biomass in the sealant layer produced only from raw materials derived from fossil fuels is 0%, and the biomass content of the sealant layer is 0%.

[0034] The biomass content in the sealant layer 12 is 5% or more, preferably 10% or more, more preferably 15% or more, and still more preferably 20% or more.

[0035] The density of the sealant layer 12 is preferably 0.91 g / cm 3 or more and 0.93 g / cm 3 or less, more preferably 0.911 g / cm 3 or more and 0.928 g / cm 3Hereinafter, more preferably 0.915 g / cm 3 or more and 0.925 g / cm 3 or less. The density is a value measured according to the method specified in Method A of JIS K7112-1980 after annealing as described in JIS K6760-1995. If the density is 0.91 g / cm 3 or more and 0.93 g / cm 3 or less, processing and molding can be facilitated.

[0036] Biomass polyethylene is a polymer of monomers containing ethylene derived from biomass. Since ethylene derived from biomass is used as the monomer which is the raw material, the polymerized polyethylene is derived from biomass. Note that the raw material monomer of polyethylene does not have to contain 100% by mass of ethylene derived from biomass. The monomer which is the raw material of biomass polyethylene may further contain a monomer of ethylene derived from fossil fuel and / or a monomer of α-olefin derived from fossil fuel, or may further contain a monomer of α-olefin derived from biomass. That is, biomass polyethylene includes biomass LLDPE in addition to biomass LDPE. Biomass MDPE and biomass HDPE are also included in the biomass polyethylene of the present invention. These may be used alone or in combination of two or more.

[0037] The above α-olefin is not particularly limited in terms of the number of carbon atoms, but usually those having 3 to 20 carbon atoms can be used, and preferably butylene, hexene, or octene. This is because if it is butylene, hexene, or octene, it can be produced by polymerization of ethylene which is a raw material derived from biomass. Further, by including such an α-olefin, the biomass polyethylene obtained by polymerization has an alkyl group as a branched structure, and thus can be made more flexible than a simple linear one.

[0038] Biomass polyethylene is preferably 0.91 g / cm 3 or more and 0.93 g / cm 3More preferably, it is 0.912 g / cm 3 or more and 0.928 g / cm 3 or less, even more preferably 0.915 g / cm 3 or more and 0.925 g / cm 3 or less. The density of the biomass polyethylene is a value measured according to the method specified in Method A of JIS K7112-1980 after annealing as described in JIS K6760-1995. If the density of the biomass polyethylene is 0.91 g / cm 3 or more, the rigidity of the sealant layer containing the biomass polyethylene can be increased, and it can be suitably used as the inner layer of the packaging bag. Also, if the density of the biomass polyethylene is 0.93 g / cm3 or less, the transparency and mechanical strength of the polyolefin resin layer containing the biomass polyethylene can be increased, and it can be suitably used as the inner layer of the packaging bag.

[0039] The melt flow rate (MFR) of the biomass polyethylene is 0.1 g / 10 min or more and 10 g / 10 min or less, preferably 0.2 g / 10 min or more and 9 g / 10 min or less, more preferably 1 g / 10 min or more and 8.5 g / 10 min or less. The MFR is a value measured by Method A under the conditions of a temperature of 190°C and a load of 21.18 N in the method specified in JIS K7210-1995. If the MFR is 0.1 g / 10 min or more, the extrusion load during molding can be reduced. Also, if the MFR is 10 g / 10 min or less, the mechanical strength of the polyolefin resin layer containing the biomass polyethylene can be increased.

[0040] In the present invention, preferably used biomass polyethylenes include low-density polyethylene derived from biomass manufactured by Braskem (trade name: SBC818, density: 0.918 g / cm 3 , MFR: 8.1 g / 10 min, biomass content 95%), low-density polyethylene derived from biomass manufactured by Braskem (trade name: SPB681, density: 0.922 g / cm 3 , MFR: 3.8 g / 10 min, biomass content 95%), and the like.

[0041] When the basis weight of the paper base material layer of the laminate 10 of the present embodiment is P, the thickness of the sealant layer 12 is S1, and the density of the sealant layer 12 is M1, the following relational expression (I) is satisfied. 0.33 < (S1 × M1) / P < 1 ···(I)

[0042] (S1 × M1) / P means the ratio of the weight of the sealant layer 12 to the weight of the paper base material layer 11 per unit area. In conventional paper cups, paper containers, etc. as described in Patent Document 1, this ratio is as large as 1 or more, that is, the basis weight of the paper is relatively large, so it does not have the flexibility like a flexible packaging material. In the present invention, by satisfying the relational expression (I), it is possible to realize a laminate 10 having flexibility excellent in bag-making suitability and dead-hold property while using biomass polyethylene.

[0043] (Pattern layer) The pattern layer 13 is a printing layer provided on the surface of the base material layer (paper base material layer 11) opposite to the sealant layer 12 and printed with a pattern. Here, the pattern refers to various aspects of recording objects that can be recorded or printed on the base material layer (paper base material layer 11), and is not particularly limited, and widely includes figures, characters, patterns, patterns, symbols, patterns, marks, etc. In particular, when the laminate 10 is used for a packaging bag intended to contain food, as the pattern, figures of the contents, characters indicating information such as the product name, expiration date, manufacturing date, and manufacturing number of the contents are used. Note that since the pattern layer 13 is laminated on the base material layer (paper base material layer 11) according to the specifications of the product, etc., the pattern layer 13 may be omitted.

[0044] Note that the ink constituting the pattern layer 13 includes a coloring pigment and a resin, but in the present invention, the resin constituting this ink, for example, nitrocellulose, may be a biomass-derived resin. Such inks are commercially available, and Cias HR (manufactured by DIC Graphic Co., Ltd.), which is a gravure ink containing a biomass resin component, can be appropriately used. Thereby, the amount of resin derived from fossil fuels used can be further reduced.

[0045] (Surface layer) The surface layer 14 is a layer provided on the pattern layer 13 and is the outermost layer of the laminate 10 when used as a packaging bag. The surface layer 14 is formed by, for example, overprint varnish (OP varnish), which can suppress the disappearance of the pattern layer 13 due to rubbing or the like and suppress the forgery of the pattern.

[0046] Note that the OP varnish of the surface layer 14 also contains a resin. In the present invention, the resin constituting this OP varnish, for example, nitrocellulose, may be a resin derived from biomass. Such inks are commercially available, and KS-10 (manufactured by DIC Graphics Co., Ltd.), which is an OP varnish containing a biomass resin component, can be appropriately used. Thereby, the amount of resin derived from fossil fuel can be further reduced.

[0047] The laminate of the above-described first embodiment can be formed, for example, by the following layer configuration.

[0048] 1) Pattern layer / Paper base material layer / Sealant layer In this case, the paper base material layer is the base material layer, and the paper base material layer is kraft paper having a basis weight of 20 g / m 2 or more and 99 g / m 2 or less. The sealant layer is a layer containing biomass LDPE, and it is desirable to be formed in the range of 20 μm or more and 60 μm or less, respectively.

[0049] 2) Pattern layer / Paper base material layer / Anchor coat layer / Sealant layer In this case, the paper base material layer is the base material layer, and the paper base material layer is kraft paper having a basis weight of 20 g / m 2 or more and 99 g / m 2 or less. The anchor coat layer is, for example, a urethane-based resin, an epoxy-based resin, or a polyolefin resin. The sealant layer is a layer containing biomass LDPE, and it is desirable to be formed in the range of 20 μm or more and 60 μm or less, respectively.

[0050] 3) Pattern layer / Paper substrate layer / Second bonding layer / Aluminum foil layer / Anchor coat layer / Sealant layer In this case, the layers from the paper substrate layer to the aluminum foil layer are the substrate layer, and the second bonding layer that bonds the paper substrate layer and the aluminum foil layer is, for example, a polyethylene resin. The paper substrate layer has a basis weight of 20 g / m 2 or more and 99 g / m 2 or less of kraft paper. The anchor coat layer is, for example, a urethane-based resin, an epoxy-based resin, or a polyolefin resin. The sealant layer is a layer containing biomass LDPE. Here, the second bonding layer is desirably formed in the range of 3 μm or more and 20 μm or less, the aluminum foil layer is desirably formed in the range of 6 μm or more and 25 μm or less, and the sealant layer is desirably formed in the range of 20 μm or more and 60 μm or less.

[0051] 4) Pattern layer / Paper substrate layer / Second bonding layer / PET layer / Anchor coat layer / Sealant layer In this case, the layers from the paper substrate layer to the PET layer are the substrate layer, and the second bonding layer that bonds the paper substrate layer and the PET layer is, for example, a polyethylene resin. The paper substrate layer has a basis weight of 20 g / m 2 or more and 99 g / m 2 or less of kraft paper. The PET layer is a sheet-like polyethylene terephthalate resin substrate. The paper substrate layer and the PET layer are bonded by the dry lamination method. The anchor coat layer is, for example, a urethane-based resin, an epoxy-based resin, or a polyolefin resin. The sealant layer is a layer containing biomass LDPE. Here, the second bonding layer is desirably formed in the range of 3 μm or more and 20 μm or less, the PET layer is desirably formed in the range of 5 μm or more and 25 μm or less, and the sealant layer is desirably formed in the range of 20 μm or more and 60 μm or less.

[0052] 5) Pattern layer / Paper substrate layer / Second bonding layer / Vapor-deposited film layer / Anchor coat layer / Sealant layer In this case, the layers from the paper substrate layer to the vapor-deposited film layer are the substrate layer, and the second bonding layer that bonds the paper substrate layer and the vapor-deposited film layer is EMAA (ethylene-methacrylic acid copolymer resin). The paper substrate layer has a basis weight of 20 g / m2 99 g / m or less 2 The kraft paper is as follows. The vapor deposition film layer is a plastic film having an oxygen and water vapor barrier layer such as a metal vapor deposition film or an inorganic oxide (metal oxide) vapor deposition film. Examples of the metal vapor deposition film include an aluminum vapor deposition film, and examples of the inorganic oxide (metal oxide) vapor deposition film include a silica vapor deposition film and an alumina vapor deposition film. Examples of the resin constituting the plastic film include polyethylene terephthalate (PET) and polyamide film (PA). The anchor coat layer is, for example, a urethane resin, an epoxy resin, or a polyolefin resin. The sealant layer is a layer containing biomass LDPE. Here, the second bonding layer is preferably formed in the range of 3 μm or more and 20 μm or less, the vapor deposition film layer is preferably formed in the range of 5 μm or more and 25 μm or less, and the sealant layer is preferably formed in the range of 20 μm or more and 60 μm or less.

[0053] 6) Pattern layer / Paper base material layer / Second bonding layer / Aluminum foil layer / Third bonding layer / PET layer / Anchor coat layer / Sealant layer In this case, the layer from the paper base material layer to the PET layer is the base material layer. The third bonding layer for bonding the aluminum foil layer and the PET layer can use, for example, a urethane resin, an epoxy resin, or a polyolefin resin, and the aluminum foil layer and the PET layer are bonded to each other by a dry lamination method. The second bonding layer for bonding the paper base material layer and the aluminum foil layer can use, for example, a polyolefin resin or a urethane resin. The paper base material layer has a basis weight of 20 g / m 2 99 g / m or less 2 The kraft paper is as follows. The PET layer is a sheet-like polyethylene terephthalate resin base material. The anchor coat layer is, for example, a urethane resin, an epoxy resin, or a polyolefin resin. The sealant layer is a layer containing biomass LDPE. Here, the second bonding layer is desirably formed in the range of 3 μm or more and 20 μm or less, the aluminum foil layer is desirably formed in the range of 6 μm or more and 25 μm or less, the third bonding layer is desirably formed in the range of 3 μm or more and 20 μm or less, the PET layer is desirably formed in the range of 5 μm or more and 25 μm or less, and the sealant layer is desirably formed in the range of 20 μm or more and 60 μm or less.

[0054] 7) Pattern layer / Paper base material layer / Anchor coat layer / Sealant layer In this case, the paper base material layer is the base material layer. The paper base material layer is the paper (barrier paper) having the above-described barrier property, and for example, Shield Plus manufactured by Nippon Paper Industries Co., Ltd. is used. For example, the basis weight of the barrier paper can be 30 g / m 2 or more and 99 g / m 2 or less. The anchor coat layer is, for example, a urethane-based resin, an epoxy-based resin, or a polyolefin resin. The sealant layer is a layer containing biomass LDPE. Here, the sealant layer is desirably formed in the range of 20 μm or more and 60 μm or less.

[0055] In each of the examples 3) to 7) of the above-described laminate, a laminate having a barrier property can be realized by providing a layer having a barrier function such as an aluminum foil layer or a PET layer in addition to the paper base material layer on the base material layer. In each of the examples 3) to 7) of the above-described laminate, the second bonding layer may contain a resin derived from biomass. Further, in each of the examples of the above-described laminate, a surface layer may be further formed on the surface of the pattern layer as necessary. Furthermore, in each of the examples of the above-described laminate, the anchor coat layer may be omitted.

[0056] Next, a second laminate according to the present invention will be described with reference to the drawings. <Laminate of the second embodiment> As shown in FIG. 2, in the laminate 10A of the second embodiment which is an example of the second invention of the present invention, a sealant layer 12A is formed via a bonding layer 15 on a base material layer including a paper base material layer 11. In this embodiment, the sealant layer 12A is formed by a conventionally known polyethylene lamination method, and the sealant layer 12A is separately formed as a sealant film.

[0057] The bonding layer 15 is an adhesive resin layer or an adhesive layer provided for bonding the base material layer and the sealant layer. For example, as the adhesive resin layer, polyethylene, EMAA, etc. can be used. When using polyethylene, it may contain biomass polyethylene. Also, as the adhesive layer, conventionally known ones can be used and are not particularly limited. For example, a two-component curable adhesive composed of a main agent and a curing agent such as a urethane-based or epoxy-based one can be appropriately used.

[0058] In the case of the adhesive resin layer, the bonding layer 15 is preferably formed so that the thickness is 5 μm or more and 30 μm or less, and more preferably 10 μm or more and 20 μm or less. If the thickness is less than 5 μm, the coating amount is insufficient and the thickness becomes too thin, making it impossible to sufficiently bond the base material layer and the sealant layer, which is not desirable. Also, when the thickness is greater than 30 μm, the coating amount is too much and the thickness becomes too thick, reducing the dead hold property and the cut-off property of the laminate, which is not desirable.

[0059] In the case of the adhesive layer, the bonding layer 15 is preferably formed so that the dry thickness is 1 μm or more and 10 μm or less, and more preferably 2 μm or more and 5 μm or less. If the dry thickness is less than 1 μm, the coating amount is insufficient and the thickness becomes too thin, making it impossible to sufficiently bond the base material layer and the sealant layer, which is not desirable. Also, when the dry thickness is greater than 10 μm, the possibility of poor drying increases, which is not desirable.

[0060] Here, from the viewpoint of improving the adhesion of the bonding layer 15 to the base material layer including the paper base material layer 11, an anchor coat layer may be provided on the surface of the base material layer where the bonding layer is formed, so that the base material layer, the anchor coat layer, and the bonding layer are laminated in this order. Here, as the material used for the anchor coat layer, for example, urethane resin, epoxy resin, polyolefin resin, etc. can be used. It is desirable that the thickness of the anchor coat layer is formed, for example, to be 0.1 μm or more and 1.0 μm or less. Also, when the bonding layer 15 is directly provided on the paper base material layer of the base material layer without providing the anchor coat layer, corona treatment may be performed on the surface of the paper base material layer on the side where the bonding layer 15 is formed to improve the adhesion of the bonding layer 15 to the paper base material layer. Note that on the surface of the paper base material layer 11 on the side opposite to the sealant layer 12A, a pattern layer 13 and a surface layer 14 are sequentially formed. Here, since the paper base material layer 11, the pattern layer 13, and the surface layer 14 are the same as those in the first embodiment, the same reference numerals are given and the description thereof is omitted.

[0061] In the laminate 10A of the present embodiment, when the bonding layer 15 is an adhesive resin layer, the total thickness S4 of the thickness S2 of the sealant layer 12A and the thickness S3 of the adhesive resin layer 15 is formed to be 20 μm or more and 60 μm or less. That is, in the relational expression (II) in the polyethylene sand lamination method, "sealant layer 12A + adhesive resin layer 15" is applied by being replaced with the sealant layer 12 in the relational expression (I) for convenience.

[0062] In this case, the biomass content is also calculated in "sealant layer 12A + adhesive resin layer 15". For this reason, biomass polyethylene may be used in the adhesive resin layer 15, may be used in the sealant layer 12A, or may be included in both the sealant layer 12A + adhesive resin layer 15.

[0063] Also, in the laminate 10A of the present embodiment, when the basis weight P of the paper base material layer, the thickness S2 of the sealant layer 12A, the density M2 of the sealant layer 12, the thickness S3 of the adhesive resin layer 15, and the density M3 of the adhesive resin layer 15 are defined, the following relational expression (II) is satisfied. 0.33 < (S2×M2 + S3×M3) / P < 1 ···(II)

[0064] By satisfying the above relational expression (II), similar to the laminate 10 of the first embodiment, a laminate 10A excellent in bag-making suitability and dead-holding property can be realized while using biomass polyethylene. When the bonding layer 15 is an adhesive layer, in the above relational expression (II), the thickness S3 of the adhesive resin layer is calculated as S3 = 0. That is, similar to the above relational expression (I), in the case of only the sealant layer, 0.33 < (S2×M2) / P < 1 is satisfied.

[0065] The laminate of the second embodiment described above can be formed, for example, with the following layer configurations.

[0066] 1) Pattern layer / Paper base material layer / Bonding layer / Sealant layer In this case, the paper base material layer is the base material layer, and the paper base material layer is kraft paper with a basis weight of 20 g / m 2 or more and 99 g / m 2 or less. The bonding layer is LDPE. The sealant layer is a layer containing biomass LDPE or biomass LLDPE. Here, it is desirable that the bonding layer is formed in the range of 10 μm or more and 20 μm or less, and the sealant layer is formed in the range of 30 μm or more and 40 μm or less, respectively.

[0067] 2) Pattern layer / Paper base material layer / Anchor coat layer / Bonding layer / Sealant layer In this case, the paper base material layer is the base material layer, and the paper base material layer is kraft paper with a basis weight of 20 g / m 2 or more and 99 g / m 2 or less. The anchor coat layer is, for example, a urethane-based resin, an epoxy-based resin, or a polyolefin resin. The bonding layer is LDPE. The sealant layer is a layer containing biomass LDPE or biomass LLDPE. Here, it is desirable that the bonding layer is formed in the range of 10 μm or more and 20 μm or less, and the sealant layer is formed in the range of 30 μm or more and 40 μm or less, respectively.

[0068] 3) Pattern layer / Paper substrate layer / Second bonding layer / Aluminum foil layer / Anchor coat layer / Bonding layer / Sealant layer In this case, the layers from the paper substrate layer to the aluminum foil layer are the substrate layer, and the second bonding layer that bonds the paper substrate layer and the aluminum foil layer is, for example, a polyethylene resin. The paper substrate layer has a basis weight of 20 g / m 2 or more and 99 g / m 2 or less of kraft paper. The anchor coat layer is, for example, a urethane resin, an epoxy resin, or a polyolefin resin. The bonding layer is LDPE. The sealant layer is a layer containing biomass LDPE or biomass LLDPE. Here, it is desirable that the second bonding layer is formed in the range of 3 μm or more and 20 μm or less, the aluminum foil layer is formed in the range of 6 μm or more and 25 μm or less, the bonding layer is formed in the range of 10 μm or more and 20 μm or less, and the sealant layer is formed in the range of 30 μm or more and 40 μm or less.

[0069] 4) Pattern layer / Paper substrate layer / Second bonding layer / PET layer / Anchor coat layer / Bonding layer / Sealant layer In this case, the layers from the paper substrate layer to the PET layer are the substrate layer, and the second bonding layer that bonds the paper substrate layer and the PET layer is, for example, a polyethylene resin. The paper substrate layer has a basis weight of 20 g / m 2 or more and 99 g / m 2 or less of kraft paper. The PET layer is a sheet-like polyethylene terephthalate resin substrate. The anchor coat layer is, for example, a urethane resin, an epoxy resin, or a polyolefin resin. The bonding layer is LDPE. The sealant layer is a layer containing biomass LDPE or biomass LLDPE. Here, it is desirable that the second bonding layer is formed in the range of 3 μm or more and 20 μm or less, the PET layer is formed in the range of 5 μm or more and 25 μm or less, the bonding layer is formed in the range of 10 μm or more and 20 μm or less, and the sealant layer is formed in the range of 30 μm or more and 40 μm or less.

[0070] 5) Pattern layer / Paper substrate layer / Second bonding layer / Vapor-deposited film layer / Anchor coat layer / Bonding layer / Sealant layer In this case, the substrate layer extends from the paper substrate layer to the vapor deposition film layer. The second bonding layer that bonds the paper substrate layer and the vapor deposition film layer is EMAA (ethylene-methacrylic acid copolymer resin). The paper substrate layer is kraft paper with a basis weight of 20 g / m 2 or more and 99 g / m 2 or less. The vapor deposition film layer is a plastic film provided with an oxygen and water vapor barrier layer such as a metal vapor deposition film or an inorganic oxide (metal oxide) vapor deposition film. Examples of the metal vapor deposition film include an aluminum vapor deposition film, and examples of the inorganic oxide (metal oxide) vapor deposition film include a silica vapor deposition film and an alumina vapor deposition film. Examples of the resin constituting the plastic film include polyethylene terephthalate (PET) and polyamide film (PA). The anchor coat layer is, for example, a urethane resin, an epoxy resin, or a polyolefin resin. The bonding layer is LDPE. The sealant layer is a layer containing biomass LDPE or biomass LLDPE. Here, it is desirable that the second bonding layer is formed in the range of 5 μm or more and 20 μm or less, the vapor deposition film layer is formed in the range of 5 μm or more and 25 μm or less, the bonding layer is formed in the range of 10 μm or more and 20 μm or less, and the sealant layer is formed in the range of 30 μm or more and 40 μm or less.

[0071] 6) Pattern layer / Paper substrate layer / Second bonding layer / Aluminum foil layer / Third bonding layer / PET layer / Anchor coat layer / Bonding layer / Sealant layer In this case, the substrate layer extends from the paper substrate layer to the PET layer. As the third bonding layer that bonds the aluminum foil layer and the PET layer, for example, a dry lamination adhesive such as a urethane resin or an epoxy resin can be used, and the aluminum foil layer and the PET layer are bonded to each other by the dry lamination method. Also, as the second bonding layer that bonds the paper substrate layer and the aluminum foil layer, for example, a polyethylene resin can be used. The paper substrate layer has a basis weight of 20 g / m 2 or more and 99 g / m 2It is the following kraft paper. The PET layer is a sheet-like polyethylene terephthalate resin base material. The anchor coat layer is, for example, a urethane resin, an epoxy resin, or a polyolefin resin. The bonding layer is LDPE. The sealant layer is a layer containing biomass LDPE or biomass LLDPE. Here, the second bonding layer is desirably formed in the range of 5 μm or more and 20 μm or less, the aluminum foil layer is desirably formed in the range of 6 μm or more and 25 μm or less, the third bonding layer is desirably formed in the range of 1 μm or more and 10 μm or less, the PET layer is desirably formed in the range of 5 μm or more and 25 μm or less, the bonding layer is desirably formed in the range of 10 μm or more and 20 μm or less, and the sealant layer is desirably formed in the range of 30 μm or more and 40 μm or less.

[0072] 7) Pattern layer / Paper base material layer / Anchor coat layer / Bonding layer / Sealant layer In this case, the paper base material layer is the base material layer. The paper base material layer is the paper (barrier paper) having the above-described barrier property, and for example, Shield Plus manufactured by Nippon Paper Industries Co., Ltd. is used. For example, the basis weight of the barrier paper can be 30 g / m 2 or more and 99 g / m 2 or less. The anchor coat layer is, for example, a urethane resin, an epoxy resin, or a polyolefin resin. The bonding layer is LDPE. The sealant layer is a layer containing biomass LDPE or biomass LLDPE. Here, the bonding layer is desirably formed in the range of 10 μm or more and 20 μm or less, and the sealant layer is desirably formed in the range of 30 μm or more and 40 μm or less.

[0073] In each of Examples 3) to 7) of the above laminate, a laminate having a barrier property can be realized by providing, in the base material layer, not only the paper base material layer but also a layer having a barrier function such as an aluminum foil layer or a PET layer. In addition, in each of Examples 3) to 6) of the above laminate, a resin derived from biomass may be used for the second bonding layer. Further, in each of the above examples of the laminate, a surface layer may be further formed on the surface of the pattern layer as needed. Furthermore, in each of the above examples of the laminate, the anchor coat layer may be omitted.

[0074] Next, the packaging bag using the laminate of the present invention will be described with reference to the drawings. The laminate 10 of the above-described first embodiment and the laminate 10A of the second embodiment can each be suitably used for a packaging bag that contains powdery or granular contents. From the viewpoint of avoiding damage (tearing) of the packaging bag when the packaging bag is dropped, etc., the capacity of the contents to be contained is preferably 1 g or more and 200 g or less.

[0075] (Pillow packaging bag) First, an example of a pillow packaging bag, which is an example of a packaging bag, will be described. FIG. 3 is a perspective view of a pillow packaging bag, which is an example of a packaging bag using the laminate of the present invention. FIG. 4 is a plan view seen from the back surface in FIG. 3 (a), a cross-sectional view taken along line a-a (b), and a cross-sectional view taken along line b-b (c).

[0076] The pillow packaging bag 50 is a pillow-shaped packaging bag formed by heat-sealing or the like the laminate 10 (10A). As shown in FIGS. 3 and 4, the pillow packaging bag 50 includes a seal portion 60 (a back seal portion 61, an upper seal portion 62, and a lower seal portion 63, which will be described later) that joins the inner surfaces (the surfaces on the sealant layer 12 side) of the laminate 10 (10A). This seal portion 60 forms a storage portion 65 for storing contents inside the pillow packaging bag 50 and is configured to seal this bag.

[0077] The pillow packaging bag 50 has a rectangular outer shape having an upper portion 52 on the upper side, a lower portion 53 on the lower side facing the upper portion 52, and a pair of side portions 54 extending from the upper portion 52 to the lower portion 53. Further, the pillow packaging bag 50 has a back surface portion 55 and a front surface portion 56 located on the opposite side thereof, and these are formed by folding back a single laminate 10 (10A). Furthermore, in the pillow packaging bag 50, a clasp portion 51 formed by overlapping the left and right side edges of a single laminate 10 (10A) with their inner surfaces facing each other is provided on the back surface portion 55 side. Note that the back surface portion 55 has a left back surface portion 55A and a right back surface portion 55B with the clasp portion 51 as a boundary.

[0078] The clasp portion 51 is formed so as to protrude from the back surface portion 55. In the present embodiment, as shown in FIGS. 3 and 4, the clasp portion 51 is tilted to the right and overlaps the right back surface portion 55B located on the right side of the clasp portion 51. Note that this is not limiting, and the clasp portion 51 may be tilted to the left and overlapped on the left back surface portion 55A.

[0079] As shown in FIGS. 4(b) and (c), the clasp portion 51 has a left clasp portion 51A and a right clasp portion 51B that are side edges of a single laminate 10 (10A). The left clasp portion 51A and the right clasp portion 51B are joined by heat-sealing their inner surfaces (the surfaces on the sealant layer 12 side) to each other, and a back seal portion 61 is formed on the clasp portion 51. As shown in FIGS. 3 and 4(a), the back seal portion 61 is provided from the upper portion 52 to the lower portion 53 along the vertical direction of the pillow packaging bag 50. The extending direction of the back seal portion 61 is substantially orthogonal to the extending directions of the upper and lower edges of the laminate 10 (10A).

[0080] An upper seal portion 62 extending along this is provided on the upper portion 52, and a lower seal portion 63 extending along this is provided on the lower portion 53. These upper seal portion 62 and lower seal portion 63 are formed by joining the inner surfaces (the surfaces on the sealant layer 12 side) of the laminate 10 (10A) to each other by heat-sealing. Here, before the contents are stored in the storage portion 65, the pillow packaging bag 50 is in an unsealed state where the upper seal portion 62 or the lower seal portion 63 is not heat-sealed, which is a seal-scheduled portion. In this embodiment, for example, before the contents are stored, the upper portion 52 of the pillow packaging bag 50 is the seal-scheduled portion. After the contents are stored in the storage portion 65, the seal-scheduled portion is heat-sealed to form the upper seal portion 62, and the contents are sealed in the pillow packaging bag 50.

[0081] As described above, since the above-mentioned pillow packaging bag 50 uses the laminate 10(10A) which is excellent in dead-hold property and has flexibility, the pillow packaging bag 50 can be easily formed from the laminate 10(10A). Also, after the pillow packaging bag 50 is opened, when the opened opening is bent and resealed, the bent state can be easily maintained. In addition, since the pillow packaging bag 50 uses a paper base material that constitutes a paper flexible package, when used as a stick package for packaging sugar or the like, the upper or lower seal portion can be easily separated by hand to open it. Moreover, since the pillow packaging bag 50 uses the laminate 10(10A) containing biomass polyethylene, the amount of fossil fuel used can be reduced compared to conventional packaging bags, and the environmental load can be reduced.

[0082] Furthermore, although the sealant layer 12 of the laminate 10(10A) used for the pillow packaging bag 50 contains biomass polyethylene, it is not inferior in physical properties such as mechanical properties compared to the sealant layer of polyethylene manufactured from raw materials obtained from fossil fuels. Therefore, when the pillow packaging bag 50 is formed, each seal portion can be formed without gaps. More specifically, as shown in FIG. 4(c), at the lower portion 53 of the pillow packaging bag 50, the back seal portion 61 and the lower seal portion 63 are formed without gaps even between the laminated bodies 10 (10A) that are folded like the portion where the palm portion 51, the front surface portion 56, and the back surface portion 55 overlap. Similarly, at the upper portion 52 of the pillow packaging bag 50, the back seal portion 61 and the upper seal portion 62 are formed without gaps even between the laminated bodies 10 (10A) that are folded like the portion where the palm portion 51, the front surface portion 56, and the back surface portion 55 overlap. As a result, the pillow packaging bag 50 formed by the laminated body 10 (10A) can sufficiently seal the storage portion 65.

[0083] (Gusset packaging bag) Next, an example in which the laminated body 10 of the first embodiment and the laminated body 10A of the second embodiment described above are applied to a gusset packaging bag, which is another example of a packaging bag, will be described. FIG. 5 is a perspective view of a gusset packaging bag, which is an example of a packaging bag using the laminated body of the present invention. FIG. 6 is a (a) plan view seen from the back, (b) cross-sectional view taken along c-c, and (c) cross-sectional view taken along d-d in FIG. 5.

[0084] The gusset packaging bag 70 is composed of a flexible rectangular laminated body 10 (10A). As shown in FIGS. 5 and 6, the gusset packaging bag 70 includes a storage portion 90 for storing contents and a seal portion 80 surrounding the storage portion 90. The laminated body 10 (10A) constituting the gusset packaging bag 70 includes a front surface portion 75 forming the front surface, a back surface portion 74 forming the back surface, side surface portions 76 forming gusset folding portions on the left and right side portions, and a palm portion 71 joining the side edge of one laminated body 10 (10A) on the back surface portion 74. That is, the gusset packaging bag 70 has a side gusset bag shape with gusset folding portions on the side portions. Looking at it another way, the gusset packaging bag 70 has a front surface formed by the front surface portion 75, a back surface formed by the back surface portion 74, and side surfaces formed by the gusset folding portions (side surface portions 76) on the side portions.

[0085] Here, on the back surface portion 74, a clasp portion 71 is provided where the side edges of one laminate 10 (10A) are overlapped as described above. When viewed from the back side, the back surface portion to the left of the clasp portion 71 is the left back surface portion 74A, and the back surface portion to the right is the right back surface portion 74B. The clasp portion 71 has a left clasp portion 71A connected to the left back surface portion 74A and a right clasp portion 71B connected to the right back surface portion 74B, and the clasp portion 71 is formed by overlapping the left clasp portion 71A and the right clasp portion 71B. The side surface portion 76 has a left side surface portion 76A on the left and a right side surface portion 76B on the right when viewed from the back side.

[0086] The gusset folding portion is provided on the side portion of the gusset packaging bag 70. When the content is stored in the storage portion 90, as shown in FIG. 5, the gusset folding portion spreads sufficiently. Therefore, the volume of the storage portion 90 can be increased compared to the case of a flat pouch without a gusset folding portion on the side portion. On the other hand, when the content is not stored in the storage portion 90, the side surface portions 76 (76A, 76B) forming the gusset folding portion are folded back by the folding portions 77 (77A, 77B) toward the clasp portion 71 side as shown in FIG. 6. As a result, the overall thickness of the gusset packaging bag 70 is reduced.

[0087] Also, the gusset packaging bag 70 is formed by one rectangular laminate 10 (10A) before bag making. More specifically, in order from one side edge of one laminate 10 (10A), the left clasp portion 71A, the left back surface portion 74A, the left side surface portion 76A, the front surface portion 75, the right side surface portion 76B, the right back surface portion 74B, and the right clasp portion 71B are connected. This laminate 10 (10A) is heat-sealed with the sealant layer 12 positioned inside the container so that the left clasp portion 71A and the right clasp portion 71B are overlapped, thereby forming a back seal portion 81 that joins the left clasp portion 71A and the right clasp portion 71B. As a result, the rectangular laminate 10 (10A) is formed into a cylindrical shape with the opposing side edges joined. Note that the inside of the laminate 10 (10A) formed into a cylindrical shape becomes the storage portion 90.

[0088] In the lower part 73 of the gusset packaging bag 70, a laminated body (front surface part 75, left side surface part 76A, back surface part 74, right side surface part 76B) formed in a cylindrical shape is folded in two by a folding part 77 so that the left and right side surface parts 76A and 76B face the clasp part 71 side between the front surface part 75 and the back surface part 74 as shown in FIG. 6(c), and the lower parts of the respective films are heat-sealed to be joined. Here, the front surface side of the side surface part 76 folded in two at the folding part 77 is joined to the front surface part 75, and the back surface side is joined to the back surface part 74. Thereby, a lower seal part 83 is formed in the lower part 73 of the gusset packaging bag 70.

[0089] Similarly, in the upper part 72 of the gusset packaging bag 70, a laminated body (front surface part 75, left side surface part 76A, back surface part 74, right side surface part 76B) formed in a cylindrical shape is folded in two by a folding part 77 so that the left and right side surface parts 76A and 76B face the clasp part 71 side between the front surface part 75 and the back surface part 74, and the upper parts of the respective films are heat-sealed to be joined. Here, the front surface side of the side surface part 76 folded in two at the folding part 77 is joined to the front surface part 75, and the back surface side is joined to the back surface part 74. Thereby, an upper seal part 82 is formed in the upper part 72 of the gusset packaging bag 70.

[0090] Note that, before the contents are stored in the gusset packaging bag 70, the upper seal part 82 or the lower seal part 83 is a seal-scheduled part in an unsealed state. By storing the contents in the storage part 90 from this seal-scheduled part and heat-sealing (joining) the seal-scheduled part, the contents can be sealed.

[0091] As described above, since the above-described gusset packaging bag 70 uses the laminate 10 (10A) having excellent dead-hold properties and flexibility, the gusset packaging bag 70 can be easily formed from the laminate 10 (10A). Further, when the opened opening is bent and resealed after the gusset packaging bag 70 is opened, the bent state can be easily maintained. In addition, since the gusset packaging bag 70 uses a paper base material layer that constitutes a paper flexible package, the upper or lower seal portion can be easily opened by manually cutting it off. In addition, since the laminate 10(10A) forming the gusset packaging bag 70 contains biomass polyethylene, the amount of fossil fuel used can be reduced compared to conventional packaging bags, and the environmental load can be reduced.

[0092] Furthermore, the sealant layer 12 of the laminate 10(10A) used for the gusset packaging bag 70 contains biomass polyethylene, but is not inferior in terms of physical properties such as mechanical properties compared to a sealant layer of polyethylene manufactured from raw materials obtained from fossil fuels. Therefore, when the gusset packaging bag 70 is formed into a bag, each seal portion can be formed without gaps. More specifically, as shown in FIG. 6(c), in the lower portion 73 of the gusset packaging bag 70, the back seal portion 81 and the lower seal portion 83 are formed without gaps even between the laminated laminates 10(10A) that are folded, such as the portion where the side surface portion 76, the front surface portion 75, and the back surface portion 74 overlap, or the portion where the clasp portion 71, the front surface portion 75, and the back surface portion 74 overlap. Similarly, in the upper portion 72 of the gusset packaging bag 70, the back seal portion 81 and the upper seal portion 82 are formed without gaps even between the laminated laminates 10(10A) that are folded, such as the portion where the side surface portion 76, the front surface portion 75, and the back surface portion 74 overlap, or the portion where the clasp portion 71, the front surface portion 75, and the back surface portion 74 overlap. Thereby, the gusset packaging bag 70 formed by the laminate 10(10A) can sufficiently seal the storage portion 90.

Example

[0093] Hereinafter, the present invention will be described in more detail based on examples. [Example 1] (Extrusion lamination configuration corresponding to the first embodiment) As the paper base material, kraft paper 60 g / m 2(Forest Certification Nagoya Sharyu, made by Oji Paper Co., Ltd.) Using Cyas HR (made by DIC Graphics Co., Ltd.), a gravure ink for the front printing of paper containing a biomass resin component, pattern printing was performed with a dry thickness of 1 μm, and then KS-10 (made by DIC Graphics Co., Ltd.) was applied as an OP (overprint) varnish on the pattern printing with a dry thickness of 1 μm. Next, on the side opposite to the printed surface of the paper substrate, as a sealant layer, SBS818 (made by Braskem, density 0.918 g / m 2 , MFR = 8.1), a biomass low-density polyethylene (LDPE), was extrusion-coated at a resin temperature of 335°C, a line speed of 100 m / min, and a thickness of 30 μm to produce a laminate with the following configuration. The biomass content of the sealant layer was 95%, and the value of (S1 × M1) / P in formula (I) was 0.46. <Layer configuration of Example 1> OP varnish / Ink / Paper substrate (60 g / m 2 ) / Biomass LDPE (30 μm)

[0094] [Example 2] (Extrusion lamination configuration corresponding to the first embodiment) In Example 1, a laminate with the following configuration was produced with the same configuration as Example 1 except that the thickness of the sealant layer of biomass LDPE was 50 μm. The biomass content of the sealant layer was 95%, and the value of (S1 × M1) / P in formula (I) was 0.77. <Layer configuration of Example 2> OP varnish / Ink / Paper substrate (60 g / m 2 ) / Biomass LDPE (50 μm)

[0095] [Example 3] (Extrusion lamination configuration corresponding to the first embodiment) In Example 1, the sealant layer was made of Kernel KC577T (made by Japan Polyethylene), a linear low-density polyethylene (LLDPE) derived from petroleum, with a thickness of 30 μm and a biomass LDPE with a thickness of 30 μm. The density was 0.910 g / m 2, except that a laminate with the following structure was manufactured with the same configuration as in Example 1, except that the resin temperature was 335°C and the line speed was 100 m / min for co-extrusion of 15 μm of MFR = 15). The biomass degree of the entire sealant layer of 45 μm was 63%, and the value of (S1×M1) / P in formula (I) was 0.69. <Layer configuration of Example 3> OP varnish / ink / paper substrate (60 g / m 2 ) / biomass LDPE (30 μm) / LLDPE (15 μm)

[0096] [Example 4] (Extrusion lamination configuration corresponding to the first embodiment) In Example 1, except that the sealant layer was blended with biomass LDPE and Novatec LC520 (manufactured by Japan Polyethylene Corporation, density 0.923 g / m 2 , MFR = 3.6) at a ratio of 1:1 and extrusion-coated with a thickness of 50 μm at a resin temperature of 335°C and a line speed of 100 m / min, a laminate with the following structure was manufactured with the same configuration as in Example 1. The biomass degree of the sealant layer was 47.5%, and the value of (S1×M1) / P in formula (I) was 0.77. <Layer configuration of Example 4> OP varnish / ink / paper substrate (60 g / m 2 ) / biomass LDPE + LDPE (50 μm)

[0097] [Example 5] (Extrusion lamination configuration corresponding to the first embodiment) In Example 1, except that the basis weight of the paper substrate was 99 g / m 2 and the thickness of the biomass LDPE was 36 μm, a laminate with the following structure was manufactured with the same configuration as in Example 1. The biomass degree of the sealant layer was 95%, and the value of (S1×M1) / P in formula (I) was 0.33. <Layer configuration of Example 5> OP varnish / ink / paper substrate (99 g / m 2 ) / biomass LDPE (36 μm)

[0098] [Example 6] (Extrusion lamination configuration corresponding to the first embodiment) In Example 1, except that the basis weight of the paper substrate was 36 g / m 2 , and the thickness of the biomass LDPE was 37 μm, a laminate with the following configuration was produced with the same configuration as in Example 1. The biomass degree of the sealant layer was 95%, and the value of (S1 × M1) / P in formula (I) was 0.94. <Layer configuration of Example 6> OP varnish / ink / paper substrate (36 g / m 2 ) / biomass LDPE (37 μm)

[0099] [Example 7] (Polyethylene sand lamination configuration corresponding to the second embodiment) As the paper substrate, kraft paper 60 g / m 2 (Forest certification, Nagoya Sharyu, manufactured by Oji Paper Co., Ltd.) was printed with a pattern in a dry thickness of 1 μm using Cyas HR (manufactured by DIC Graphics Co., Ltd.), a gravure ink for surface printing of paper containing a biomass resin component. Next, KS-10 (manufactured by DIC Graphics Co., Ltd.) was applied as an OP varnish on the pattern printing in a dry thickness of 1 μm. Next, biomass low-density polyethylene (LDPE) with a biomass degree of 95% was formed into a film with a thickness of 40 μm by the inflation method (manufactured by Dainippon Printing Co., Ltd.). The paper after OP varnish application and the above-mentioned 40-μm biomass LDPE film were used as an adhesive resin layer through 15 μm of SBS818 (manufactured by Braskem, density 0.918 g / m 2 , MFR = 8.1), and polyethylene sand lamination was performed at a resin temperature of 335°C and a line speed of 100 m / min to produce a laminate with the following configuration. The biomass degree in the total 55 μm of the adhesive resin layer (15 μm) + sealant layer (40 μm) was 95%, and the value of (S2 × M2 + S3 × M3) / P in relational expression (II) was 0.84. <Layer configuration of Example 7> OP varnish / ink / paper substrate (60 g / m 2 ) / biomass LDPE (15 μm) / biomass LDPE film (40 μm)

[0100] [Example 8] (Extrusion lamination structure corresponding to the first embodiment) In Example 1, except that the paper base material was barrier paper 66 g / m 2 (Shield Plus, manufactured by Nippon Paper Industries Co., Ltd.), the same structure as in Example 1 was used to produce a laminate with the following structure. The biomass degree of the sealant layer was 95%, and the value of (S1×M1) / P in formula (I) was 0.42. <Layer structure of Example 8> OP varnish / ink / paper base material (66 g / m 2 ) / biomass LDPE (30 μm)

[0101] [Comparative Example 1] In Example 1, except that the thickness of the biomass LDPE in the sealant layer was 18 μm, the same structure as in Example 1 was used to produce a laminate with the following structure. The biomass degree of the sealant layer was 95%, and the value of (S1×M1) / P in formula (I) was 0.28. <Layer structure of Comparative Example 1> OP varnish / ink / paper base material (60 g / m 2 ) / biomass LDPE (18 μm)

[0102] [Comparative Example 2] In Example 7, except that the biomass LDPE film was 60 μm, the same structure as in Example 7 was used to produce a laminate with the following structure. The biomass degree in the total 75 μm of the adhesive resin layer (15 μm) + sealant layer (60 μm) was 95%, and the value of (S2×M2 + S3×M3) / P in relational expression (II) was 1.15.

[0103] The laminates of the above examples and comparative examples are summarized in Table 1.

[0104] [Evaluation of bag-making suitability]

[0105] [Evaluation of bag-making suitability] Using the laminates prepared in the examples and comparative examples, pillow packaging bags (width 40 mm × length 100 mm, back seal 10 mm, top and bottom seals 10 mm), and side gusset bags (width 60 mm × length 200 mm, side fold 10 mm, back seal 10 mm, top and bottom seals 10 mm) were produced. After production, the filling of the seal part was checked with the product name "Ageless (registered trademark) Seal Check", and it was evaluated as ○ when there was no leakage of the checking liquid and × when there was leakage.

[0106] [Dead hold property confirmation] Regarding the laminates of the examples and comparative examples, they were folded in half so that the sealant layer was on the outside and the base material layer was on the inside. After squeezing the fold by hand, the folded state when left at room temperature for 30 seconds was visually confirmed. It was evaluated as ○ when the folded state was maintained and × when it was returning to the original state. The evaluation results are summarized in Table 2.

[0107]

Table 2

[0108] As shown in Table 2, in the examples, both the bag-making suitability and the dead hold property were good. On the other hand, in Comparative Example 1, the value of (S1×M1) / P was smaller than the range of the present invention, and the filling of the seal part was insufficient at the position where the laminates overlapped. For example, in the case of the pillow packaging bag, as shown in Fig. 4(c), the filling of the seal part was insufficient at the portion where the clasp parts 51 (51A, 51B), the front surface part 56, and the back surface part 55 overlapped. Also, in the case of the gusset packaging bag, as shown in Fig. 6(c), the filling of the seal part was insufficient at the portion where the clasp parts 71 (71A, 71B), the front surface part 75, and the back surface part 74 overlapped, and at the portion where the two-folded side surface parts 76, the front surface part 75, and the back surface part 74 overlapped. Also, in Comparative Example 2, it can be understood that the value of (S2×M2 + S3×M3) / P is larger than the range of the present invention and is inferior in dead hold property.

Explanation of symbols

[0109] 10, 10A Laminates 11 Paper Substrate Layer 12, 12A Sealant Layers 13 Pattern Layer 14 Surface Layer 50 Pillow Packaging Bag 51 Clasp Portion 52 Upper Portion 53 Lower Portion 54 Side Portion 55 Back Surface Portion 56 Front Surface Portion 61 Back Seal Portion 62 Upper Seal Portion 63 Lower Seal Portion 70 Gusset Packaging Bag 71 Clasp Portion 72 Upper Portion 73 Lower Portion 74 Back Surface Portion 75 Front Surface Portion 76 Side Surface Portion 81 Back Seal Portion 82 Upper Seal Portion 83 Lower Seal Portion

Claims

1. A laminate in which a sealant layer is formed directly or via an anchor coat layer on a base layer including at least a paper base layer, The paper base layer has a basis weight P of 20 g / m ２ 99g / m or more ２ is as follows: The sealant layer contains biomass polyethylene, which is a polymer of a monomer containing ethylene derived from biomass, and has a biomass content of 5% or more; The sealant layer has, in order from the base layer side, a layer of biomass polyethylene and a layer of fossil fuel-derived polyethylene, The sealant layer has a thickness S １ is 20 μm or more and 60 μm or less, The basis weight P of the paper base layer and the thickness S of the sealant layer １ , the density M of the sealant layer １ , satisfies the following relation (I): 0.33<(S １ ×M １ ) / P<1 ・・・(I)

2. A laminate in which an adhesive resin layer or adhesive layer and a sealant layer are formed in this order on a base layer including at least a paper base layer, either directly or via an anchor coat layer, The paper base layer has a basis weight P of 20 g / m ２ 99g / m or more ２ is as follows: The sealant layer and / or the adhesive resin layer contain biomass polyethylene which is a polymer of a monomer containing ethylene derived from biomass, and the biomass degree of the sealant layer and the adhesive resin layer is 5% or more; The sealant layer has, in order from the base layer side, a layer of biomass polyethylene and a layer of fossil fuel-derived polyethylene, The thickness S of the sealant layer ２ and the thickness S of the adhesive resin layer ３ The total thickness S ４ is 20 μm or more and 60 μm or less, The basis weight P of the paper base layer and the thickness S of the sealant layer ２ , the density M of the sealant layer ２ , the thickness S of the adhesive resin layer ３ , the density M of the adhesive resin layer ３ , satisfies the following relational formula (II). 0.33<(S ２ ×M ２ +S ３ ×M ３ ) / P<1 ・・・(II)

3. A pillow packaging bag formed using the laminate according to claim 1 or 2.

4. A gusseted packaging bag formed using the laminate according to claim 1 or 2.

5. The packaging bag according to claim 3 or 4, A packaging bag, wherein the contents contained in the packaging bag are powder or granules.

Images