Laminated film and package

Abstract

To provide a laminated film that can be employed in manufacturing a base material of a press-through package, the laminated film including a biomass-derived resin and enabling production of the base material having high shape retention of recesses, and to provide a package formed with the laminated film.SOLUTION: A laminated film 1 is provided wherein an inner layer 11, an intermediate layer 12, and an outer layer 13 are laminated in this order in the thickness direction. The inner layer 11 and the outer layer 13 comprise a propylene-based polymer, and the intermediate layer 12 comprises biomass-derived polyethylene. In the laminated film 1, a test piece having a recess depressed in the thickness direction of the laminated film 1 is prepared. The recess has an inner diameter of 10 mm at its opening and a depth of 5 mm, and the buckling strength of the recess is 11-20 N. Also provided is a package constituted using the laminated film 1.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a laminated film and a packaging material. [Background technology]

[0002] A press-through package (also referred to as "PTP" in this specification) is a package in which a base material with a recess and a sheet-like lid material are heat-sealed, and a storage compartment is formed by the recess and the lid material, and is widely used for packaging tablets.

[0003] Laminated films formed by laminating multiple resin layers are widely used in various types of packaging because multiple properties are often required of packaging (see Patent Document 1). In PTPs, a transparent laminated film molded body is typically used as the base material, and an aluminum sheet is used as the lid material. The base material is required to have several properties, such as heat sealing to enable it to be sealed with the lid material, moisture resistance to prevent moisture from penetrating into the storage compartment, and shape retention to maintain the shape of the recess that makes up the storage compartment. Furthermore, because the laminated film is transparent, the contents, such as tablets, can be visually observed through the base material in PTPs. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2007-283569 Summary of the Invention [Problem to be solved by the invention]

[0005] While synthetic resins produced from petroleum-derived raw materials are currently the mainstream of resins, in recent years, the use of biomass-derived resins produced from animal and plant-derived raw materials has been considered in the packaging field. Since the production of biomass-derived resins can reduce carbon dioxide emissions compared to the production of petroleum-derived resins, increasing the amount of biomass-derived resin used not only reduces the consumption of petroleum resources but also enables the construction of packaging that places less strain on the environment.

[0006] In contrast, among packaging materials, the use of biomass-derived resins, particularly PTPs, has not been fully explored. PTPs are unique in that, unlike other packaging materials, the lid material is torn by pressing a recess constituting the storage compartment in the base material, thereby removing the stored contents, such as tablets. The recess in the base material must be able to easily remove the stored contents by pressing, but even before that, it is preferable that the shape of the recess be shape-retaining so that it is not easily deformed by unintended pressing. In contrast, the PTP disclosed in Patent Document 1 is not designed for this purpose.

[0007] An object of the present invention is to provide a laminated film that can be used to manufacture a base material for a press-through package, the laminated film containing a biomass-derived resin and capable of manufacturing the base material having high shape retention of recesses, and a packaging body constructed using the laminated film. [Means for solving the problem]

[0008] In order to solve the above problems, the present invention employs the following configuration. [1] A laminated film constructed by laminating an inner layer, an intermediate layer, and an outer layer in this order in the thickness direction, wherein the inner layer and the outer layer contain a propylene-based polymer, and the intermediate layer contains biomass-derived polyethylene. A test piece of the laminated film is prepared with a recess recessed in the thickness direction, and the opening of the recess has an inner diameter of 10 mm, a depth of 5 mm, and a buckling strength of 11 to 20 N. [2] The laminate film according to [1], wherein, when the tensile strength of the laminate film is measured in accordance with JIS K 7127:1999, the tensile strength ratio of [MD tensile strength of the laminate film] / [TD tensile strength of the laminate film] is 1 to 1.3. [3] The laminated film according to [1] or [2], wherein the Young's modulus of the laminated film measured in accordance with JIS K 7161-1:2014 is 1000 MPa or more. [4] The laminate film according to any one of [1] to [3], wherein a 15 mm wide test piece obtained by dry laminating the inner layer in the laminate film and a biaxially oriented polyethylene terephthalate film with a urethane adhesive is used, and when the laminate of the inner layer and the biaxially oriented polyethylene terephthalate film is peeled from the intermediate layer at a peel rate of 50 mm / min so that the surface of the inner layer facing the intermediate layer forms an angle of 180° with the surface of the intermediate layer facing the inner layer in the test piece, the measured peel strength is 10 N / 15 mm or more.

[0009] [5] A packaging body constructed using the laminated film according to any one of [1] to [4]. [6] The packaging body described in [5], which comprises a lid material and a base material, the packaging body being formed by sealing the lid material and the base material, and the base material being formed using the laminated film. [Effects of the Invention]

[0010] According to the present invention, there are provided a laminated film that can be used to manufacture a base material for a press-through package, the laminated film containing a biomass-derived resin and capable of manufacturing the base material having high shape retention of the recessed portion, and a packaging body constructed using the laminated film. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a cross-sectional view schematically illustrating an example of a laminated film according to one embodiment of the present invention. [Figure 2]10 is a diagram showing an example of the relationship between the load measured when the storage section of the press-through package is pressed by the pressing means and the displacement of the pressing means. FIG. [Figure 3] 1 is a perspective view schematically illustrating an example of a packaging body according to an embodiment of the present invention. [Figure 4] 4 is a cross-sectional view of the packaging body shown in FIG. 3 taken along line IV-IV. DETAILED DESCRIPTION OF THE INVENTION

[0012] <<Laminated film>> A laminated film according to one embodiment of the present invention is constructed by laminating an inner layer, an intermediate layer, and an outer layer in this order in the thickness direction, wherein the inner layer and the outer layer contain a propylene-based polymer, and the intermediate layer contains biomass-derived polyethylene. A test piece is prepared from the laminated film, having a recess recessed in the thickness direction, and the opening of the recess has an inner diameter of 10 mm, a depth of 5 mm, and a buckling strength of 11 to 20 N. In the laminate film of the present embodiment, the intermediate layer contains biomass-derived polyethylene, and therefore the environmental impact during production is smaller than that of conventional laminate films that do not contain biomass-derived resins. When unintended pressure is applied to a recess in the base material of a press-through package (PTP) obtained using the laminated film of this embodiment (in other words, the storage section of the PTP), the shape of the recess is not easily deformed by this pressure, and the recess has high shape retention.

[0013] In this specification, unintended pressure on the recess in the base material (the storage section of the PTP) does not refer to intentional pressure on the recess in order to remove the contents from the PTP, but rather to pressure that is accidentally applied to the recess even though it is not intended to remove the contents from the PTP. For example, unintended pressure would be pressure applied to the recess during any handling process such as transporting, storing, or distributing the PTP.

[0014] In this specification, the shapes of the recesses in the test specimen and the recesses in the base material described below are concave when viewed from the opening side, but the shapes when viewed from the opposite side may be referred to as "convex." Similarly, the shape of the storage compartment in the PTP described below when viewed from its bottom side may be referred to as "convex."

[0015] The laminated film of this embodiment preferably has transparency throughout.

[0016] FIG. 1 is a cross-sectional view schematically showing an example of the laminated film of the present embodiment. In addition, the figures used in the following explanation may show enlarged essential parts for the sake of convenience in order to make the features of the present invention easier to understand, and the dimensional ratios of each component may not necessarily be the same as in reality.

[0017] The laminated film 1 shown here is constructed by laminating an inner layer 11, an intermediate layer 12, and an outer layer 13 in this order in the thickness direction. In the laminated film 1, the inner layer 11 is the outermost layer on one side, and the outer layer 13 is the outermost layer on the other side. In the thickness direction of the laminated film 1, the intermediate layer 12 is disposed between the inner layer 11 and the outer layer 13. The surface 11b of the inner layer 11 opposite the intermediate layer 12 (sometimes referred to as the "second surface" in this specification) is the exposed surface, one of the outermost surfaces of the laminated film 1, and the sealing surface when the laminated film 1 or its molded body is heat-sealed to another film or its molded body. The surface 13a of the outer layer 13 opposite the intermediate layer 12 (sometimes referred to as the "first surface" in this specification) is the exposed surface, the other outermost surface of the laminated film 1, and is also the exposed surface in a package obtained by heat-sealing the laminated film 1 or its molded body with another film or its molded body.

[0018] The inner layer 11 and the outer layer 13 contain a propylene-based polymer. The intermediate layer 12 comprises biomass-derived polyethylene. The buckling strength of the recess of the test piece obtained using the laminated film 1 is 11 to 20N.

[0019] The properties of the laminated film of this embodiment will be described below.

[0020] <Buckling strength of recess in test piece> In this specification, the buckling strength of the recess in the test piece more specifically refers to the buckling strength of the storage section in a test PTP that is made using the test piece corresponding to the base material and a lid material and in which tablets are packed as the contents, and means the strength required for the side surface of the storage section in the test PTP to collapse. The buckling strength of the storage section in the test PTP corresponds to the load at which the second peak is reached among the loads measured when the deepest point of the storage section is pressed from the outside toward the opening along the depth direction of the storage section using a pressing means. FIG. 2 shows a typical relationship between the displacement of the pushing means (in other words, the pushing distance) when the storage section in the PTP is pushed in and the measured load, regardless of whether it is for testing or not.

[0021] As shown in FIG. 2, when the storage section in the PTP is pressed by the pressing means, the load applied to the storage section by the pressing means increases as the pressing means displaces, and the load applied to the area of ​​the lid that constitutes the storage section via the stored item also increases. The lid then breaks, and at that moment, the stored item loses some of the support provided by the lid, reducing the load applied to the storage section. At this time, a first load peak P1 is observed. When the storage section in the PTP is subsequently pressed by the pressing means, the load applied to the storage section by the pressing means increases again as the pressing means displaces. As a result, the side of the storage section (recess) collapses (the buckling region of the storage section), the stored item completely loses support from the lid, and the stored item is pushed out of the storage section. The load applied to the storage section decreases, and a second load peak P2 is observed. In this embodiment, the load at which this second peak P2 is observed is used as the buckling strength of the storage section.

[0022] In this embodiment, the buckling strength of the storage section of the test PTP is measured using the method described above.

[0023] The opening of the recess of the test piece is circular or nearly circular (approximately circular) and has an inner diameter of 10 mm. In this specification, nearly circular means a shape that is not circular but is so close to a circle that it cannot be clearly recognized as non-circular by visual inspection. On the other hand, the depth of the recess is 5 mm. The bottom surface of the recess may be either flat or non-flat (for example, curved), and if it is non-flat, the depth of the deepest part of the recess should be 5 mm. The shape of the recess is not particularly limited as long as it satisfies these conditions, but it is preferable that the opening of the recess (cross-sectional opening) when a cross section of the recess is formed in a direction parallel to the surface of the flat portion (region where no recess is provided) of the test piece has a similar shape to the opening, i.e., is circular or approximately circular.

[0024] The pushing means used for the test PTP has a flat surface on the side that comes into contact with the test PTP, a circular shape, and a diameter of 5 mm. The material of the pushing means is not particularly limited as long as it has a strength sufficient to prevent the pushing means from deforming when the storage section is pushed in, and preferred materials include, for example, metal and resin.

[0025] In this embodiment, the buckling strength of the recess of the test piece is 11 to 20 N. When the buckling strength is equal to or greater than the lower limit, the shape retention of the recess (in other words, the shape retention of the storage portion) is high. On the other hand, when the buckling strength is equal to or less than the upper limit, it is easy to intentionally remove the stored item from the PTP. In terms of improving the shape retention of the recesses, the buckling strength of the recesses of the test piece may be, for example, either 12.5 to 20N or 14 to 20N. The buckling strength of the recess of the test piece may be, for example, either 11 to 17 N or 11 to 14 N, so that the stored item can be more easily removed when the stored item is intentionally removed from the PTP.

[0026] The buckling strength of the recess in the test specimen (the storage area in the PTP) can be adjusted by adjusting the type and content of the components in any layer of the laminated film and the thickness of that layer. In particular, the buckling strength can be easily increased by increasing the content of biomass-derived polyethylene in the intermediate layer and increasing the thickness of the intermediate layer.

[0027] <Tensile strength ratio of laminated film> When the tensile strengths of the laminate film in the MD and TD are measured in accordance with JIS K 7127:1999, the tensile strength ratio (sometimes simply referred to as the "tensile strength ratio" in this specification) of [tensile strength of laminate film in the MD] / [tensile strength of laminate film in the TD] is preferably 1 to 1.3. When the tensile strength ratio is in this range, the difference between the thickness along the MD and the thickness along the TD is small in the molded portion of the laminate film molded body (for example, the recessed portion of the base material). In other words, the thickness variation in both the MD and TD directions in the molded portion of the molded body is suppressed, and the thickness uniformity is increased.

[0028] In this specification, "MD" means the machine direction of the resin, and "TD" means the transverse direction perpendicular to the MD of the resin.

[0029] When measuring the tensile strength of the laminated film, the pulling speed of the laminated film is preferably 50 mm / min, and the temperature of the laminated film is preferably 20°C.

[0030] The tensile strength ratio may be, for example, any one of 1 to 1.11, 1.09 to 1.21, and 1.19 to 1.3.

[0031] The tensile strength ratio can be adjusted by adjusting the tensile strength in the MD and the tensile strength in the TD of the laminated film.

[0032] The tensile strength in the MD of the laminated film is not particularly limited as long as it satisfies the tensile strength ratio, but is preferably 2000 to 4500 N / cm 2 Preferably, the strength is 2300 to 4000 N / cm 2 More preferably, it is 2600 to 3500 N / cm 2 It is more preferable that the MD tensile strength of the laminate film is equal to or greater than the lower limit, which increases the effect of suppressing tearing of the laminate film during production of the laminate film and during production of a molded article using the laminate film. When the MD tensile strength of the laminate film is equal to or less than the upper limit, the laminate film can be more easily molded.

[0033] The TD tensile strength of the laminated film is not particularly limited as long as it satisfies the above tensile strength ratio, but is preferably 2000 to 4500 N / cm 2 Preferably, the strength is 2300 to 4000 N / cm 2 More preferably, it is 2600 to 3500 N / cm 2 It is more preferable that the TD tensile strength of the laminate film is equal to or greater than the lower limit, which increases the effect of suppressing tearing of the laminate film during production of the laminate film and during production of a molded article using the laminate film. When the TD tensile strength of the laminate film is equal to or less than the upper limit, the laminate film can be more easily molded.

[0034] The MD and TD tensile strengths of the laminate film can be adjusted by adjusting the type and content of components contained in any layer of the laminate film and the thickness of that layer. In particular, the MD and TD tensile strengths can be easily increased by using a resin with a high molecular weight or by reducing the thickness of the inner or outer layer.

[0035] <Young's modulus of laminated film> The Young's modulus of the laminate film, measured in accordance with JIS K 7161-1:2014, is preferably 1000 MPa or more, more preferably 1100 MPa or more, and may be, for example, any of 1160 MPa or more, 1220 MPa or more, and 1280 MPa or more. When the Young's modulus of the laminate film is equal to or greater than the lower limit, the effect of suppressing tearing of the laminate film during production of the laminate film and during production of a molded article using the laminate film is enhanced. The upper limit of the Young's modulus of the laminate film is not particularly limited. For example, a laminate film having a Young's modulus of 1400 MPa or less can be more easily achieved.

[0036] The Young's modulus of the laminate film may be either the Young's modulus in the MD of the laminate film or the Young's modulus in the TD of the laminate film, or both the Young's modulus in the MD and the Young's modulus in the TD of the laminate film may be within the above-mentioned numerical range.

[0037] The MD Young's modulus and TD Young's modulus of the laminate film can be adjusted by adjusting the type and content of components contained in any layer of the laminate film and the thickness of that layer. In particular, the MD Young's modulus and TD Young's modulus can be easily increased by increasing the content of biomass-derived polyethylene in the intermediate layer and increasing the thickness of the intermediate layer.

[0038] <Peel strength between inner layer and middle layer> A 15 mm-wide test piece was prepared by dry laminating the inner layer of the laminate film to a biaxially oriented polyethylene terephthalate film using a urethane adhesive. When the laminate of the inner layer and the biaxially oriented polyethylene terephthalate film was peeled from the intermediate layer at a peel rate of 50 mm / min so that the surface of the inner layer facing the intermediate layer formed an angle of 180° with the surface of the intermediate layer facing the inner layer (i.e., when a 180° peel was performed), the measured peel strength was preferably 10 N / 15 mm or greater. Having the peel strength at or above the lower limit suppresses peeling between the inner layer and the intermediate layer, improving the peel resistance of the laminate film. In this case, for example, when a user of a PTP attempts to peel the lid from the base material in the PTP, the inner layer in the base material is prevented from peeling from the intermediate layer in the base material along with the lid material. Instead, the lid material peels normally from the inner layer in the base material, maintaining the proper appearance of the base material after peeling the lid material. This allows the base material to have a good appearance after the lid material has been peeled off. Peeling the lid material from the base material is not a normal operation when removing contents from a PTP, but even when such an unintended operation is performed, the condition of the base material is maintained normal as long as the peel strength is equal to or greater than the lower limit.

[0039] In order to enhance the above-mentioned effect, the peel strength between the inner layer and the intermediate layer is preferably 12 N / 15 mm or more, and may be, for example, either 14 N / 15 mm or more or 16 N / 15 mm or more. The upper limit of the peel strength is not particularly limited. For example, a laminated film having a peel strength of 25 N / 15 mm or less can be more easily achieved.

[0040] The urethane adhesive is not particularly limited as long as it is an adhesive that utilizes the reaction between polyol and polyisocyanate, and may be any known adhesive. The biaxially oriented polyethylene terephthalate film is not particularly limited as long as the inner layer can be peeled from the intermediate layer without damaging the inner layer.

[0041] The laminate of the inner layer and the biaxially oriented polyethylene terephthalate film is preferably peeled from the intermediate layer at normal temperature, such as room temperature.

[0042] In this specification, "room temperature" means a temperature that is neither particularly cold nor hot, that is, an ordinary temperature, and examples thereof include temperatures of 15 to 25°C.

[0043] The peel strength between the inner layer and the intermediate layer can be adjusted by adjusting the type and content of the components contained in the inner layer and the intermediate layer, as well as the thickness of the inner layer. In particular, the peel strength can be easily increased by making the inner layer contain the same components as those contained in the intermediate layer and increasing the content of those components in the inner layer or by increasing the thickness of the inner layer. Examples of components contained in both the inner layer and the intermediate layer include propylene-based polymers and petroleum resins, which will be described later.

[0044] The laminated film of this embodiment preferably satisfies two or more of the above-mentioned tensile strength ratio, Young's modulus, and peel strength between the inner layer and the intermediate layer, and more preferably satisfies all of them.

[0045] Next, each layer constituting the laminated film of this embodiment will be described.

[0046] <Inner layer> Since the inner layer contains a propylene-based polymer, the laminated film or its molded article (e.g., base material) can be heat-sealed well to other sheets, films, or molded articles thereof, and the laminated film or its molded article has appropriate rigidity.

[0047] In this specification, unless otherwise specified, the term "propylene-based polymer" refers to a polymer (resin) having at least structural units derived from propylene, and may be a homopolypropylene (propylene homopolymer, hPP) having only structural units derived from propylene, or a propylene-based copolymer having structural units derived from propylene and structural units derived from a monomer other than propylene. That is, the inner layer may contain homopolypropylene (hPP) or a propylene copolymer as the propylene polymer.

[0048] Examples of the propylene-based copolymer contained in the inner layer include propylene-ethylene random copolymer (also known as polypropylene random copolymer, rPP), propylene-ethylene block copolymer (also known as polypropylene block copolymer, bPP), and ethylene-propylene terpolymer (also known as ethylene propylene terpolymer, EPT).

[0049] The melting point of the propylene polymer contained in the inner layer is preferably 150 to 170°C, more preferably 155 to 165°C. The melt flow rate (sometimes referred to as "MFR" in this specification) of the propylene polymer contained in the inner layer is preferably 1 to 4 g / 10 min, and more preferably 2 to 3 g / 10 min.

[0050] In this specification, unless otherwise specified, "MFR" refers to a value measured in accordance with JIS K 6922-1.

[0051] The inner layer may or may not contain other components that are not propylene-based polymers. Examples of the other components contained in the inner layer include petroleum resins and additives. For example, when the inner layer contains the petroleum resin, the water vapor barrier properties (in other words, moisture resistance) of the laminated film are improved.

[0052] Examples of the petroleum resin include known resin components obtained by polymerizing mainly a C5 fraction or a C9 fraction from the remaining fraction after fractions such as ethylene, propylene, and butadiene are extracted from the thermal decomposition product of petroleum naphtha.

[0053] More specific examples of the petroleum resin include aliphatic hydrocarbon resin-based petroleum resins, aromatic hydrocarbon resin-based petroleum resins, alicyclic saturated hydrocarbon resin-based petroleum resins, and copolymer-based petroleum resins. Preferred petroleum resins include, for example, aliphatic hydrocarbon resin-based petroleum resins, which have high transparency and little odor. Among these, more preferred petroleum resins include dicyclopentadiene-based petroleum resins having structural units derived from dicyclopentadiene, and even more preferred petroleum resins include hydrogenated dicyclopentadiene-based petroleum resins obtained by thermally polymerizing dicyclopentadiene followed by a hydrogenation reaction.

[0054] Examples of the additives include various additives known in the art, such as antifogging agents, antiblocking agents, antioxidants, antistatic agents, crystal nucleating agents, inorganic particles, viscosity reducers, thickeners, heat stabilizers, lubricants, infrared absorbers, and ultraviolet absorbers.

[0055] The propylene-based polymer and the other components (e.g., petroleum resin, additives) contained in the inner layer may each be of only one type or of two or more types. When two or more types are contained, the combination and ratio thereof can be selected arbitrarily depending on the purpose.

[0056] The inner layer preferably contains a propylene-based polymer and a petroleum resin.

[0057] In the inner layer, the ratio of the propylene polymer content to the total mass of the inner layer ([propylene polymer content in inner layer (parts by mass)] / [total mass of inner layer (parts by mass)]×100) is preferably 70 to 100% by mass, more preferably 80 to 100% by mass, and may be, for example, 85 to 100% by mass. When the ratio is equal to or greater than the lower limit, the properties of the inner layer become better. The ratio is usually the same as the ratio of the content of the propylene-based polymer to the total content (parts by mass) of components that do not vaporize at room temperature in the resin composition for forming the inner layer, which will be described later ([content (parts by mass) of the propylene-based polymer in the resin composition for forming the inner layer] / [total content (parts by mass) of components that do not vaporize at room temperature in the resin composition for forming the inner layer]×100). The relationship between the content of the components contained in any layer constituting the laminate film and the content of the components contained in the resin composition for forming that layer is also the same for layers other than the inner layer described below.

[0058] When the inner layer contains a petroleum resin, the content of the petroleum resin in the inner layer relative to the total mass of the inner layer is preferably 3% by mass or more, and may be, for example, 6% by mass or more or 8% by mass or more. When the content is equal to or more than the lower limit, the effect obtained by containing the petroleum resin in the inner layer is further enhanced. On the other hand, the ratio is preferably 30% by mass or less, and may be, for example, 20% by mass or less or 15% by mass or less. When the ratio is equal to or less than the upper limit, the effects obtained by the inner layer containing the propylene-based polymer and the petroleum resin can be obtained in a balanced manner. The ratio may be within a range set by any combination of any of the above-mentioned lower limit values ​​and any of the above-mentioned upper limit values.

[0059] In the inner layer, the ratio of the total content of the propylene-based polymer and the petroleum resin to the total mass of the inner layer (([Propylene-based polymer content in the inner layer (parts by mass)] + [Petroleum resin content in the inner layer (parts by mass)]) / [Total mass of the inner layer (parts by mass)] × 100) is preferably 80 to 100 mass%, more preferably 90 to 100 mass%, and may be, for example, either 95 to 100 mass% or 97 to 100 mass%. When the ratio is equal to or greater than the lower limit, the properties of the inner layer become particularly good. Here, when the inner layer does not contain a petroleum resin, the content of the petroleum resin in the inner layer is 0 parts by mass.

[0060] In the inner layer, the content of the biomass-derived polyethylene relative to the total mass of the inner layer is preferably 0 to 10% by mass, and may be, for example, 0 to 5% by mass, 0 to 2% by mass, or 0% by mass (i.e., the inner layer does not contain biomass-derived polyethylene). When the content is equal to or less than the upper limit, the properties of the inner layer become better.

[0061] In this specification, for any of the components contained in any of the layers constituting the laminate film, including the inner layer described above, the percentage of the content of the component in the relevant layer relative to the total mass of the relevant layer is described, but the total value of the percentages described for each component shall not exceed 100 mass% in the relevant layer.

[0062] The inner layer may consist of one layer (single layer) or two or more layers. When the inner layer consists of multiple layers, these multiple layers may be the same or different from each other, and the combination of these multiple layers is not particularly limited as long as it does not impair the effects of the present invention. The inner layer preferably consists of one layer (single layer).

[0063] In this specification, not limited to the case of inner layers, "multiple layers may be the same or different from one another" means "all layers may be the same, all layers may be different, or only some layers may be the same," and further, "multiple layers are different from one another" means "at least one of the constituent materials and thicknesses of each layer is different from one another."

[0064] The thickness of the inner layer is preferably 25 to 60 μm, more preferably 30 to 55 μm, and even more preferably 35 to 50 μm. When the thickness of the inner layer is equal to or greater than the lower limit, the peel strength between the inner layer and a layer (e.g., an intermediate layer) disposed in direct contact with the inner layer in the laminate film is increased. Furthermore, the rigidity of the laminate film or a molded article thereof is increased. When the thickness of the inner layer is equal to or less than the upper limit, the inner layer is prevented from becoming excessively thick. When the inner layer is made up of multiple layers, it is preferable that the total thickness of these multiple layers be within the above-mentioned numerical range. This is not limited to the inner layer, but also applies to layers other than the inner layer described below.

[0065] The ratio of the thickness of the inner layer to the thickness of the laminated film is preferably 5 to 25% for the same reasons as in the case of the thickness described above. When the inner layer is made up of multiple layers, it is preferable that the ratio of the total thickness of these multiple layers to the thickness of the laminated film is within the above-mentioned range, which is not limited to the inner layer but also applies to layers other than the inner layer described below.

[0066] In this specification, for any layer constituting the laminate film, not limited to the case of the inner layer described above, the ratio of the thickness of that layer to the thickness of the laminate film is described, but the total value of the ratios described for each layer shall not exceed 100%.

[0067] The inner layer is preferably transparent and is preferably a non-stretched layer.

[0068] <Outer layer> When the outer layer contains a propylene-based polymer, the layers other than the outer layer (for example, the inner layer and intermediate layer) are protected, and the laminated film or its molded article has appropriate rigidity.

[0069] The propylene-based polymer contained in the outer layer may be the same as the propylene-based polymer contained in the inner layer, and the outer layer may contain homopolypropylene (hPP) or a propylene-based copolymer as the propylene-based polymer.

[0070] The outer layer may or may not contain other components that are not propylene-based polymers. The other components contained in the outer layer include the same components as those contained in the inner layer (for example, petroleum resin, additives, etc.). For example, when the outer layer contains the petroleum resin, the water vapor barrier properties (in other words, moisture resistance) of the laminated film are improved.

[0071] The propylene-based polymer and the other components (for example, petroleum resin, additives) contained in the outer layer may each be of only one type or of two or more types. When two or more types are contained, the combination and ratio thereof can be selected arbitrarily depending on the purpose.

[0072] The outer layer preferably contains a propylene-based polymer and a petroleum resin.

[0073] The outer layer may be the same as or different in composition from the inner layer. That is, the components contained in the outer layer and the components contained in the inner layer may be the same or different, and when the outer layer contains the same component as the inner layer, the content (parts by mass) of that same component in the outer layer may be the same as or different from the content (parts by mass) of that component in the inner layer. In terms of composition, the outer layer and the inner layer being the same means that all components contained in the outer layer and all components contained in the inner layer are identical, and the content (parts by mass) of each component in the outer layer and the content (parts by mass) of each component in the inner layer are identical.

[0074] In the outer layer, the proportion of the propylene polymer content relative to the total mass of the outer layer is preferably 70 to 100 mass%, more preferably 80 to 100 mass%, and may be, for example, 85 to 100 mass%. When the proportion is equal to or greater than the lower limit, the properties of the outer layer become better. The ratio of the propylene polymer content in the outer layer to the total mass of the outer layer may be the same as or different from the ratio of the propylene polymer content in the inner layer to the total mass of the inner layer, and is preferably the same. When the ratios are the same, the curl suppression effect of such a laminate film is enhanced.

[0075] When the outer layer contains a petroleum resin, the proportion of the petroleum resin in the outer layer relative to the total mass of the outer layer is preferably 3% by mass or more, and may be, for example, 6% by mass or more or 8% by mass or more. When the proportion is equal to or greater than the lower limit, the effect obtained by including the petroleum resin in the outer layer is further enhanced. On the other hand, the ratio is preferably 30% by mass or less, and may be, for example, 20% by mass or less or 15% by mass or less. When the ratio is equal to or less than the upper limit, the effects obtained by the outer layer containing the propylene-based polymer and the petroleum resin can be obtained in a balanced manner. The ratio may be within a range set by any combination of any of the above-mentioned lower limit values ​​and any of the above-mentioned upper limit values. The ratio of the petroleum resin content in the outer layer to the total mass of the outer layer may be the same as or different from the ratio of the petroleum resin content in the inner layer to the total mass of the inner layer, but is preferably the same. When they are the same, the curl suppression effect of such a laminate film is enhanced.

[0076] In the outer layer, the ratio of the total content of the propylene-based polymer and the petroleum resin to the total mass of the outer layer is preferably 80 to 100 mass%, more preferably 90 to 100 mass%, and may be, for example, either 95 to 100 mass% or 97 to 100 mass%. When the ratio is equal to or greater than the lower limit, the properties of the outer layer become particularly good. Here, when the outer layer does not contain a petroleum resin, the content of the petroleum resin in the outer layer is 0 parts by mass. The ratio of the total content of the propylene-based polymer and the petroleum resin in the outer layer to the total mass of the outer layer may be the same as or different from the ratio of the total content of the propylene-based polymer and the petroleum resin in the inner layer to the total mass of the inner layer, and is preferably the same. When the ratios are the same, the curl suppression effect of such a laminate film is enhanced.

[0077] In the outer layer, the proportion of the biomass-derived polyethylene relative to the total mass of the outer layer is preferably 0 to 10 mass%, and may be, for example, 0 to 5 mass%, 0 to 2 mass%, or 0 mass% (i.e., the outer layer does not contain biomass-derived polyethylene). When the proportion is equal to or less than the upper limit, the properties of the outer layer become particularly good.

[0078] The outer layer may consist of one layer (single layer) or two or more layers. When the outer layer consists of multiple layers, these multiple layers may be the same or different, and the combination of these multiple layers is not particularly limited as long as it does not impair the effects of the present invention. The outer layer preferably consists of one layer (single layer).

[0079] The thickness of the outer layer is preferably 25 to 60 μm, more preferably 30 to 55 μm, and even more preferably 35 to 50 μm. When the thickness of the outer layer is equal to or greater than the lower limit, the effect of the outer layer in protecting the layers other than the outer layer and the rigidity of the laminated film or its molded article are enhanced. When the thickness of the outer layer is equal to or less than the upper limit, the outer layer is prevented from becoming excessively thick.

[0080] The ratio of the thickness of the outer layer to the thickness of the laminated film is preferably 5 to 25% for the same reasons as in the case of the thickness described above.

[0081] The thickness of the outer layer may be the same as or different from the thickness of the inner layer. The thickness of the outer layer is preferably 0.9 to 1.1 times, more preferably 0.95 to 1.05 times, and even more preferably 0.97 to 1.03 times, the thickness of the inner layer, which enhances the curl suppression effect of such a laminated film.

[0082] The outer layer is preferably transparent and is preferably a non-stretched layer.

[0083] In the laminated film, it is more preferable that the outer and inner layers are identical to each other in terms of composition and thickness, since this type of laminated film has a particularly high curl suppression effect.

[0084] <Middle class> By including polyethylene in the intermediate layer, the moisture-proof property and formability of the laminated film and the package obtained using the same are improved. Furthermore, because the polyethylene is biomass-derived, the amount of petroleum-derived resin used can be reduced during the production of the laminated film, thereby curbing consumption of petroleum resources. Furthermore, since the production of biomass-derived polyethylene produces less carbon dioxide than the production of petroleum-derived polyethylene, the use of biomass-derived polyethylene can contribute to reducing the environmental impact.

[0085] Examples of biomass-derived polyethylene (PE) contained in the intermediate layer include biomass-derived low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), metallocene-catalyzed linear low-density polyethylene (mLLDPE), medium-density polyethylene (MDPE), and high-density polyethylene (HDPE). In terms of highly effective improvement in the moisture resistance of the laminated film and the packaging body, the biomass-derived polyethylene contained in the intermediate layer is preferably biomass-derived high-density polyethylene.

[0086] In this specification, the density of low density polyethylene (LDPE), linear low density polyethylene (LLDPE), and metallocene-catalyzed linear low density polyethylene (mLLDPE), whether biomass-derived or not, is 0.910 g / cm 3 More than 0.945g / cm 3 is less than. Similarly, the density of medium density polyethylene (MDPE) is 0.945 g / cm 3 More than 0.955g / cm 3 is less than. Similarly, the density of high density polyethylene (HDPE) is 0.955 g / cm 3 That's all.

[0087] The melting point of the biomass-derived polyethylene contained in the intermediate layer is preferably 120 to 140°C, and more preferably 125 to 135°C. The melt flow rate (MFR) of the biomass-derived polyethylene contained in the intermediate layer is preferably 0.01 to 2 g / 10 min, and more preferably 0.1 to 1 g / 10 min.

[0088] The intermediate layer may or may not contain other components that are not included in the biomass-derived polyethylene. Examples of the other components contained in the intermediate layer include propylene polymers, petroleum resins, polyethylene not derived from biomass (in other words, polyethylene derived from petroleum), additives, and the like.

[0089] For example, when both the intermediate layer and the adjacent layer disposed in direct contact with the intermediate layer contain the propylene-based polymer, the peel strength between the intermediate layer and the adjacent layer is increased, and when the intermediate layer and the adjacent layer contain the same type of propylene-based polymer, the peel strength between the intermediate layer and the adjacent layer is further increased. Similarly, for example, when both an intermediate layer and an adjacent layer disposed in direct contact with the intermediate layer contain the petroleum resin, the peel strength between the intermediate layer and the adjacent layer is higher. Furthermore, when the intermediate layer and the adjacent layer contain the same type of petroleum resin, the peel strength between the intermediate layer and the adjacent layer is even higher. In either case, the adjacent layers include, for example, an inner layer and an outer layer.

[0090] For example, when the intermediate layer contains a petroleum resin, the water vapor barrier properties (in other words, moisture resistance) of the laminated film are improved.

[0091] The propylene-based polymer contained in the intermediate layer may be the same as the propylene-based polymer contained in the inner layer, and the propylene-based polymer contained in the intermediate layer may be homopolypropylene (hPP) or a propylene-based copolymer. The petroleum resin and additives contained in the intermediate layer may be the same as those contained in the inner layer.

[0092] The biomass-derived polyethylene and the other components (e.g., propylene-based polymer, petroleum resin, non-biomass-derived polyethylene, additives) contained in the intermediate layer may each be of only one type or of two or more types, and when two or more types are contained, the combination and ratio thereof can be selected arbitrarily depending on the purpose.

[0093] The intermediate layer preferably contains biomass-derived polyethylene, and either or both of a propylene-based polymer and a petroleum resin.

[0094] In the intermediate layer, the content of the biomass-derived polyethylene relative to the total mass of the intermediate layer is preferably 65 to 100 mass%, more preferably 75 to 100 mass%, and may be, for example, 85 to 100 mass%. When the content is equal to or greater than the lower limit, the properties of the intermediate layer become better, and further, the laminate film is more preferable as an environmentally friendly resin film.

[0095] When the intermediate layer contains a propylene-based polymer, the content of the propylene-based polymer in the intermediate layer relative to the total mass of the intermediate layer is preferably 3% by mass or more, and may be, for example, 6% by mass or more or 8% by mass or more. When the content is equal to or more than the lower limit, the effect obtained by including the propylene-based polymer in the intermediate layer is further enhanced. On the other hand, the ratio is preferably 30% by mass or less, and may be, for example, 20% by mass or less or 15% by mass or less. When the ratio is equal to or less than the upper limit, the effects obtained by the intermediate layer containing the biomass-derived polyethylene and the propylene-based polymer are obtained in a balanced manner. The ratio may be within a range set by any combination of any of the above-mentioned lower limit values ​​and any of the above-mentioned upper limit values.

[0096] When the intermediate layer contains a petroleum resin, the content of the petroleum resin in the intermediate layer relative to the total mass of the intermediate layer is preferably 7% by mass or more, and may be, for example, 12% by mass or more or 17% by mass or more. When the content is equal to or more than the lower limit, the effect obtained by including the petroleum resin in the intermediate layer is further enhanced. On the other hand, the ratio is preferably 35% by mass or less, and may be, for example, 25% by mass or less or 15% by mass or less. When the ratio is equal to or less than the upper limit, the effects obtained by the intermediate layer containing the biomass-derived polyethylene and the petroleum resin are obtained in a balanced manner. The ratio may be within a range set by any combination of any of the above-mentioned lower limit values ​​and any of the above-mentioned upper limit values.

[0097] In the intermediate layer, the ratio of the total content of the biomass-derived polyethylene, the propylene-based polymer, and the petroleum resin to the total mass of the intermediate layer is preferably 80 to 100 mass%, more preferably 90 to 100 mass%, and may be, for example, either 95 to 100 mass% or 97 to 100 mass%. When this ratio is equal to or greater than the lower limit, the properties of the intermediate layer become particularly good. Here, when the intermediate layer does not contain a propylene-based polymer, the content of the propylene-based polymer in the intermediate layer is 0 parts by mass. Similarly, when the intermediate layer does not contain a petroleum resin, the content of the petroleum resin in the intermediate layer is 0 parts by mass.

[0098] When the intermediate layer and the adjacent layer (e.g., one or both of the inner layer and the outer layer) contain the same type of propylene polymer, the ratio of the content of the same type of propylene polymer as the propylene polymer contained in the adjacent layer to the total content of propylene polymers in the intermediate layer (the total content of the same type of propylene polymer as the propylene polymer contained in the adjacent layer and the propylene polymers other than the same type of propylene polymer) is preferably 80% by mass or more, more preferably 90% by mass or more, and may be, for example, 94% by mass or more or 97% by mass or more. When this ratio is equal to or greater than the lower limit, the effect obtained by containing the same type of propylene polymer in the intermediate layer and the adjacent layer is enhanced. On the other hand, the ratio is 100% by mass or less. For the same reason, the ratio of the content of the same propylene-based polymer as the propylene-based polymer contained in the intermediate layer to the total content of propylene-based polymers (the total content of the same propylene-based polymer as the propylene-based polymer contained in the intermediate layer and the propylene-based polymers different from the same propylene-based polymer) in the adjacent layer is preferably 80% by mass or more, more preferably 90% by mass or more, and may be, for example, 94% by mass or more or 97% by mass or more. Meanwhile, the ratio is 100% by mass or less.

[0099] When the intermediate layer and the adjacent layer (e.g., one or both of the inner and outer layers) contain the same type of petroleum resin, the ratio of the content of the same type of petroleum resin as the petroleum resin contained in the adjacent layer to the total content of petroleum resins in the intermediate layer (the total content of petroleum resins of the same type as the petroleum resin contained in the adjacent layer and petroleum resins other than the same type) is preferably 80% by mass or more, more preferably 90% by mass or more, and may be, for example, 94% by mass or more or 97% by mass or more. When this ratio is equal to or greater than the lower limit, the effect obtained by the intermediate layer and the adjacent layer containing the same type of petroleum resin is enhanced. On the other hand, when this ratio is equal to or less than 100% by mass. Furthermore, for the same reason, in the adjacent layer, the ratio of the content of the same type of petroleum resin as the petroleum resin contained in the intermediate layer to the total content of petroleum resins (the total content of the same type of petroleum resin as the petroleum resin contained in the intermediate layer and the different type of petroleum resin) is preferably 80% by mass or more, more preferably 90% by mass or more, and may be, for example, 94% by mass or more or 97% by mass or more. Meanwhile, the ratio is 100% by mass or less.

[0100] The intermediate layer may consist of one layer (single layer) or two or more layers. When the intermediate layer consists of multiple layers, these multiple layers may be the same or different from each other, and the combination of these multiple layers is not particularly limited as long as it does not impair the effects of the present invention. The intermediate layer preferably consists of one layer (single layer).

[0101] The thickness of the intermediate layer is preferably 140 to 280 μm, more preferably 160 to 260 μm, and even more preferably 180 to 240 μm. When the thickness of the intermediate layer is equal to or greater than the lower limit, the moisture resistance of the laminated film and the package is improved. When the thickness of the intermediate layer is equal to or less than the upper limit, excessive thickness of the intermediate layer can be avoided.

[0102] The ratio of the thickness of the intermediate layer to the thickness of the laminated film is preferably 60 to 80% for the same reasons as in the case of the thickness described above.

[0103] The intermediate layer is preferably transparent and is preferably a non-stretched layer.

[0104] <Other layers> The laminated film of the present embodiment may or may not include a layer other than the inner layer, intermediate layer, or outer layer. The type of the other layer is not particularly limited and can be selected arbitrarily depending on the purpose. The thickness of the other layer is not particularly limited, and can be selected arbitrarily depending on the type of the other layer. When the laminated film has the other layers, the positions and number of the other layers in the laminated film are not particularly limited and can be selected arbitrarily depending on the type or purpose of the other layers.

[0105] In the laminated film, it is preferable that the inner layer and the intermediate layer are laminated in direct contact with each other, and that the intermediate layer and the outer layer are laminated in direct contact with each other. By using such a laminated film, the shape retention of the recess in the base material (the PTP storage area) is improved.

[0106] <Thickness of laminated film> The thickness (total thickness) of the laminate film is not particularly limited, but is preferably 200 to 400 μm, and may be, for example, either 215 to 385 μm or 230 to 370 μm. When the thickness of the laminate film is equal to or greater than the lower limit, the strength of the laminate film becomes higher. When the thickness of the laminate film is equal to or less than the upper limit, the laminate film can be made thinner and can be more easily formed.

[0107] <Example of laminated film> In the laminated film, The content (parts by mass) of the component contained in the inner layer in the inner layer is multiplied by the ratio of the thickness of the inner layer to the thickness of the laminated film to obtain a corrected content, and the total corrected content C of the components contained in the inner layers is the sum of the corrected contents of all the components contained in all the inner layers. X (parts by mass) was calculated, The content (parts by mass) of the components contained in the intermediate layer in the intermediate layer is multiplied by the ratio of the thickness of the intermediate layer to the thickness of the laminated film to obtain a corrected content, and the total corrected content C of the components contained in the intermediate layer is the sum of the corrected contents of all the components contained in all the intermediate layers. Y (parts by mass) was calculated, The content (parts by mass) of the component contained in the outer layer in the outer layer is multiplied by the ratio of the thickness of the outer layer to the thickness of the laminated film to obtain a corrected content, and the total corrected content C of the outer layer-containing components is the sum of the corrected contents of all the components contained in all the outer layers. Z (parts by mass) was calculated, The content (parts by mass) of the component contained in the other layer is multiplied by the ratio of the thickness of the other layer to the thickness of the laminated film to obtain a corrected content, and the total corrected content C of the components contained in the other layers is the sum of the corrected contents of all the components contained in all the other layers. W (parts by mass) is calculated, and when the laminated film does not have the other layer, W is 0 (parts by mass), Said C Xand the aforementioned C Y and the aforementioned C Z and the aforementioned C W The total corrected content C of the components contained in the laminated film is the sum of V (parts by mass) was calculated, The content (parts by mass) of the biomass-derived polyethylene contained in the intermediate layer is multiplied by the ratio of the thickness of the intermediate layer to the thickness of the laminated film to obtain a corrected content, and the total corrected content C of biomass-derived polyethylene is the sum of the corrected contents of all the biomass-derived polyethylenes contained in all the intermediate layers. Yb When calculating (parts by mass), Said C V C Yb The content C of the biomass-derived polyethylene in the laminated film is Vb is preferably 20% by mass or more. Said C Vb A laminated film in which the content of polyethylene derived from biomass is large is more preferable as an environmentally friendly resin film.

[0108] Said C Vb The higher the value, the more preferable the laminated film is as an environmentally friendly resin film. Vb may be, for example, 25% by mass or more, 40% by mass or more, or 50% by mass or more. On the other hand, the above C Vb A laminated film in which the content is 75 mass % or less can be more easily realized.

[0109] Said C X When calculating the above, the components contained in the inner layer include the propylene-based polymer and the other components (for example, petroleum resin, additives). Said C Y When calculating the above, the components contained in the intermediate layer include the biomass-derived polyethylene and the other components (for example, propylene-based polymers, petroleum resins, non-biomass-derived polyethylene, and additives). Said C ZWhen calculating the above, the components contained in the outer layer include the propylene-based polymer and the other components (for example, petroleum resin, additives).

[0110] An example of a preferred laminate film of the present embodiment is a laminate film configured by laminating an inner layer, an intermediate layer, and an outer layer in this order in the thickness direction, the inner layer and the outer layer contain a propylene-based polymer and a petroleum resin, the intermediate layer contains biomass-derived polyethylene, and either or both of a propylene-based polymer and a petroleum resin, A test piece was prepared in the laminated film, having a recess recessed in the thickness direction thereof, the opening of the recess having an inner diameter of 10 mm and a depth of 5 mm, The buckling strength of the recessed portion is 11 to 20 N.

[0111] Another example of a preferred laminate film of the present embodiment is a laminate film configured by laminating an inner layer, an intermediate layer, and an outer layer in this order in the thickness direction, the inner layer and the outer layer contain a propylene-based polymer, the intermediate layer comprises biomass-derived polyethylene; A test piece was prepared in the laminated film, having a recess recessed in the thickness direction thereof, the opening of the recess having an inner diameter of 10 mm and a depth of 5 mm, The buckling strength of the recess is 11 to 20 N, the components contained in the outer layer and the components contained in the inner layer are the same; The thickness of the outer layer is 0.9 to 1.1 times the thickness of the inner layer.

[0112] The laminated film of the present embodiment is not limited to the above-described embodiment, and some of the configuration may be changed, deleted, or added within the scope of the gist of the present invention.

[0113] <<Laminated film manufacturing method>> The laminated film can be produced, for example, by a feed block method in which resins or resin compositions, etc., which are materials for forming each layer, are melt-extruded using several extruders; a coextrusion T-die method such as a multi-manifold method; or an air-cooled or water-cooled coextrusion inflation method.

[0114] When the resin composition is used, for example, a mixture of two or more components (dry blend, non-kneaded mixture) may be directly fed into the extruder as the resin composition, or a pre-kneaded mixture of two or more components may be fed into the extruder as the resin composition. The pre-kneaded mixture can be obtained, for example, by melt-kneading two or more components using a device such as a twin-screw extruder or a Banbury mixer.

[0115] The laminated film can also be produced by separately preparing two or more films to constitute any two or more of the layers in advance, and then laminating them together using a thermal lamination method or the like without using an adhesive, and then further laminating other layers as needed to achieve the desired arrangement.

[0116] The resin composition used to form any layer in the laminated film may be produced by adjusting the types and contents of the components contained therein so that the layer to be formed contains the desired components in the desired amounts. For example, the ratio of the contents of the components that do not vaporize at room temperature in the resin composition is usually the same as the ratio of the contents of the components in the layer formed from this resin composition.

[0117] Examples of the resin compositions for forming the inner layer and the outer layer each include a resin composition containing the propylene-based polymer and, if necessary, the other components described above. The resin composition for forming the intermediate layer may be, for example, a resin composition containing the biomass-derived polyethylene and, if necessary, the other components.

[0118] <<Packaging>> A packaging body according to one embodiment of the present invention is constructed using the laminated film according to one embodiment of the present invention described above.

[0119] The packaging body of this embodiment is constructed using the laminated film, and therefore contains a biomass-derived resin, making it an environmentally friendly packaging body. The packaging body of this embodiment is constructed using a molded body of the laminated film, and the molded body has high shape retention. For example, if a base material with a recess formed therein is used as the molded body and this is heat-sealed to a lid material to construct a PTP in which the recess forms a storage compartment, even if unintended pressure is applied to the recess (in other words, the storage compartment of the PTP) from its protruding side, the shape of the recess is not easily deformed by this pressure, and the shape retention of the recess is high.

[0120] That is, an example of a preferred packaging body in this embodiment is a packaging body having a lid material and a base material, the packaging body being formed by sealing the lid material and the base material, and the base material being formed using the laminated film.

[0121] Fig. 3 is a perspective view schematically showing an example of the packaging body of this embodiment, and Fig. 4 is a cross-sectional view of the packaging body shown in Fig. 3 taken along line IV-IV. In FIG. 3 and subsequent figures, the same components as those shown in the figures already described are given the same reference numerals as in the figures already described, and detailed description thereof will be omitted.

[0122] The package 101 shown here is a PTP (press-through package) and is configured to include a lid material 8 and a base material 9. The lid material 8 is preferably an aluminum sheet. The base material 9 is configured using the laminated film according to one embodiment of the present invention, and more specifically, is a molded body of the laminated film.

[0123] The base material 9 has recesses 91 formed in a plurality of locations, each protruding from one surface 9a (sometimes referred to herein as the "first surface") and having an opening on the other surface 9b (sometimes referred to herein as the "second surface"). In the packaging body 101, the base material 9 is disposed with its second surface 9b facing the lid material 8, and its first surface 9a is one of the outermost surfaces (exposed surfaces) of the packaging body 101.

[0124] When the base material 9 is a molded body of the laminated film 1 shown in Figure 1, the first surface 9a of the base material 9 corresponds to the first surface 13a of the outer layer 13 of the laminated film 1, and the second surface 9b of the base material 9 corresponds to the second surface 11b of the inner layer 11.

[0125] One surface 8a of the lid material 8 (sometimes referred to as the "first surface" in this specification) is the other outermost surface (exposed surface) of the packaging body 101, and in the packaging body 101, the lid material 8 is positioned with its other surface 8b (sometimes referred to as the "second surface" in this specification) facing the base material 9.

[0126] The packaging body 101 is constructed by sealing (heat sealing) the second surface 8b of the lid material 8 and the area of ​​the second surface 9b of the base material 9 where the recess 91 is not provided, and the area of ​​the second surface 9b of the base material 9 where the recess 91 is provided is not sealed to the second surface 8b of the lid material 8, and in this area, a storage section 198 is formed by the second surface 9b of the base material 9 and the second surface 8b of the lid material 8. The storage section 198 of the package 101 stores the storage item 7 in a sealed state.

[0127] The shape of the recess 91 is the same as the shape of the recess of the above-mentioned test piece. The inner diameter of the opening of the recess 91 is preferably 5 to 15 mm, and more preferably 8 to 13 mm. The depth of the recess 91 is preferably 2 to 10 mm, and more preferably 4 to 7 mm.

[0128] The planar shape of the package 101 is rectangular. In the package 101, two rows of storage sections 198 are provided in the width direction, and four rows of storage sections 198 are provided in the length direction, so that storage sections 198 are provided in a total of eight locations.

[0129] A slit 92 is formed on the first surface 9a side of the base material 9. More specifically, in the base material 9, a plurality of slits 92 are formed parallel to one another in the width direction of the packaging body 101. Each slit 92 is formed across the entire width direction of the packaging body 101. The formation of the slits 92 makes it possible to easily divide the packaging body 101 into a specific number of storage sections 198, making the packaging body 101 more convenient.

[0130] The thickness of the base material 9 may be, for example, the same as the thickness of the laminated film described above. The thickness of the lid material 8 is preferably 10 to 30 μm, and more preferably 15 to 25 μm.

[0131] The contents 7 are preferably tablets. Examples of tablets include those having physical properties similar to those of ordinary pharmaceuticals in terms of hardness, etc.

[0132] The base material 9 is made of the laminated film and therefore contains a resin derived from biomass. When unintended pressure is applied to the recess 91 (in other words, the storage section 198) in the base material 9 of the packaging body 101 from outside the first surface 9a side of the base material 9, the shape of the recess 91 is not easily deformed by this pressure, and the shape retention of the recess 91 is high. On the other hand, when the recess 91 in the base material 9 is pressed from the outside of the first surface 9a side of the base material 9 in order to intentionally remove the stored item 7 from the package 101, the stored item 7 can be easily removed.

[0133] The packaging body of this embodiment is not limited to the above-described aspects, and some of the configuration may be changed, deleted, or added within the scope of the spirit of the present invention. For example, in the packaging body 101, two rows of storage sections 198 are provided in the width direction and four rows of storage sections 198 are provided in the length direction, but in the packaging body of this embodiment, the number of storage sections provided in the width direction and length direction is not limited to these. For example, in the package 101, the opening of the recess 91 in the base material 9 is circular or nearly circular (approximately circular), but in the package of this embodiment, the opening of the recess in the base material may have any other shape. Similarly, when a cross section of the recess is formed in a direction parallel to the surface (first surface) of the flat portion of the base material (the area where the recess is not provided), the opening of the recess may be circular or nearly circular, or may have any other shape. The shape of the recess can be set as desired depending on the shape of the item to be stored.

[0134] <Example of packaging> An example of a preferred package of this embodiment is a package configured using the laminated film according to one embodiment of the present invention, The packaging body comprises a lid material and a base material, the base material is a molded body of the laminated film, The lid material is an aluminum sheet, The packaging body may be configured by sealing the lid material and the base material.

[0135] <<Packaging manufacturing method>> The packaging body can be manufactured by heat-sealing the laminated film or its molded body (e.g., base material) and the object to be sealed (e.g., lid material) while forming a storage section and storing the object to be packaged in the storage section.

[0136] The laminated film molded article such as the base material can be produced by a known method. For example, the molding pressure is preferably 0.1 to 0.5 MPa, and the molding temperature is preferably 120 to 140°C.

[0137] When heat sealing the laminated film or its molded body with the object to be sealed, the sealing temperature is preferably 200 to 270° C., the sealing pressure is preferably 0.1 to 0.5 MPa, and the sealing time is preferably 0.01 to 1 second. [Example]

[0138] The present invention will be described in more detail below with reference to specific examples, although the present invention is not limited to the examples shown below.

[0139] The resins used in each example or comparative example are as follows. bHDPE: Biomass-derived high-density polyethylene (Braskem "SGM9450F", density 0.952 g / cm 3 , melting point 131℃, MFR 0.33g / 10min) hPP: Homopolypropylene (Prime Polymer "E122V", density 0.91 g / cm 3 , melting point 160℃, MFR 2.6g / 10min) PR: Hydrogenated dicyclopentadiene petroleum resin (ENEOS Corporation "T-REZ OP501")

[0140] [Example 1] <<Laminated film manufacturing>> <Production of Resin Composition> The hPP (90 parts by mass) and the PR (10 parts by mass) were mixed at room temperature to prepare a resin composition (11). The bHDPE (80 parts by mass) and the PR (20 parts by mass) were mixed at room temperature to prepare a resin composition (21).

[0141] <Laminated film manufacturing> The resin composition (11), the resin composition (21), and the resin composition (11) were co-extruded and molded in this order to obtain a long laminated film (thickness 300 μm) having the configuration shown in FIG. 1, in which an inner layer (thickness 45 μm), an intermediate layer (thickness 210 μm), and an outer layer (thickness 45 μm) were laminated in this order in the thickness direction. The inner layer, the intermediate layer, and the outer layer are all unstretched layers.

[0142] <<Evaluation of laminated film>> <Buckling strength measurement> A 100 mm wide test laminate film was cut from the laminate film obtained above. Using a PTP packaging machine, a molding temperature of 136°C and a molding pressure of 0.15 MPa were used to form two rows of five recesses along the length of the test laminate film, totaling 10 recesses extending from the inner layer to the outer layer. This produced test specimens for buckling strength measurement. The distance between adjacent recesses in the two rows was the same in both the length and width directions of the test specimen. The openings of the recesses in the test specimens were all circular with an inner diameter of 10 mm, and all recesses were 5 mm deep.

[0143] Furthermore, using a PTP packaging machine, the test piece obtained above and an aluminum film (thickness 20 μm) were heat-sealed to form a storage compartment while storing a tablet in the storage compartment, to prepare a package. The sealing temperature was 230°C, the sealing pressure was 0.35 MPa, and the conveying speed was 11 m / min. A test PTP was obtained by cutting out an area from the obtained package that contained 10 storage sections corresponding to the above-mentioned 10 recesses, measured 37 mm x 94 mm, and had a rectangular planar shape.

[0144] For each of the ten storage compartments in the test PTP obtained above, the deepest point of the storage compartment was pressed from the outside toward the opening, along the depth direction of the storage compartment, using the pressing means described above. The load at this time was measured, and the load at which the second peak P2 was reached was determined. The average of these loads at the ten locations was calculated, and this average value was used as the buckling strength. Furthermore, the shape retention of the recesses in the base material of the PTP was evaluated based on this buckling strength according to the following criteria. The results are shown in Table 1. [Evaluation criteria] A: The buckling strength is 11 to 20N, and the recesses retain their shape well. B: The buckling strength is 7N or more but less than 11N, and the shape retention of the recess is insufficient. C: The buckling strength is less than 7N, and the shape retention of the recesses is poor, or the buckling strength is more than 20N, and the recesses are too hard, making it difficult to remove the tablet from the test PTP.

[0145] <Calculation of tensile strength ratio> Test pieces for tensile strength measurement were cut from the laminated film obtained above. Using a tensile strength measuring device ("TENSILON" manufactured by A&D Co., Ltd.), the MD tensile strength of the test piece (laminated film) was measured at a temperature of 20°C at a pulling rate of 50 mm / min in accordance with JIS K 7127:1999. Furthermore, the TD tensile strength of a separately cut test piece was measured in the same manner at a temperature of 20°C. The tensile strength ratio (MD tensile strength / TD tensile strength) was calculated from these measurements. Furthermore, this tensile strength ratio was evaluated according to the following criteria. The results are shown in Table 1. [Evaluation criteria] A: The tensile strength ratio is 1 to 1.3, which is excellent. B: The tensile strength ratio is greater than 1.3 and less than 1.6, which is insufficient. C: The tensile strength ratio is 1.6 or more, which is significantly inferior.

[0146] <Evaluation of thickness uniformity in two directions of recesses in the base material> The same test specimens as those used for measuring the buckling strength were prepared. At all (10) recesses in the test, the thickness of one shoulder portion along the MD was measured, and the average value T of the measurements at all recesses (10 measurements) was calculated. MD Similarly, the thickness of the shoulder portion at one point along the TD is measured, and the average value T of the measurements (10 measurements) at all recesses is calculated. TD Furthermore, T MD -T TD The thickness uniformity of the recesses in two directions (MD, TD) was evaluated based on the calculated value according to the following criteria. The results are shown in Table 1. [Evaluation criteria] A:T MD -T TD The thickness is less than 20 μm, and the thickness uniformity in two directions is high. B:T MD -T TD is 20 μm or more and less than 40 μm, and the thickness uniformity in two directions is insufficient. C:T MD -T TD is 40 μm or more, and the thickness uniformity in two directions is low.

[0147] <Measurement of Young's modulus> Test pieces for measuring Young's modulus were cut from the laminated film obtained above. The longitudinal direction of the test piece was aligned with the MD of the test piece. Using an autograph testing machine ("TENSILON" manufactured by A&D Co., Ltd.), the tensile stress and strain of the test piece (laminated film) were measured at a temperature of 25°C at a tension speed of 2 mm / min in accordance with JIS K 7161-1:2014, and the Young's modulus was calculated from these measurements. Furthermore, this Young's modulus was evaluated according to the following criteria. The results are shown in Table 1. [Evaluation criteria] A: Young's modulus is 1000 MPa or more, which is excellent. B: Young's modulus is 800 MPa or more and less than 1000 MPa, which is insufficient. C: Young's modulus is less than 800 MPa, and is significantly inferior.

[0148] <Evaluation of punchability during molding> The laminate film obtained above was punched 10 times to a size of 37 mm x 94 mm, simulating the molding process. The number of times that the laminate film adhered to the punching blade was counted, and the punchability of the laminate film during molding was evaluated based on the number of times according to the following criteria. The quality of this punchability is an indicator of the effectiveness of suppressing tearing of the laminate film during the production of molded articles using the laminate film, as described above. The results are shown in Table 1. [Evaluation criteria] A: Adhesion occurred 0 times out of 10 (no adhesion occurred), and punching properties during molding were high. B: Adhesion occurred 1 to 2 times out of 10 times, and punching properties during molding were insufficient. C: Adhesion occurred 3 or more times out of 10 times, and punching ability during molding was poor.

[0149] <Measurement of peel strength between inner layer and middle layer> A two-component thermosetting polyurethane adhesive ("A-616" manufactured by Mitsui Chemicals, Inc.) diluted with ethyl acetate was applied to the exposed surface of the inner layer of the laminated film obtained above, and a biaxially oriented polyethylene terephthalate film ("E5101" manufactured by Toyobo Co., Ltd., thickness 19 μm) was dry laminated to the exposed surface of the adhesive. The resulting laminated sheet was then left to stand in an environment of 40°C for 12 hours.

[0150] The laminate sheet was then returned to room temperature, and a 15 mm wide test piece for measuring peel strength was cut from the laminate sheet. At one longitudinal end of the test piece, the laminate of the inner layer and biaxially oriented polyethylene terephthalate film was slightly peeled from the intermediate layer. Furthermore, the end of the laminate and the end of the laminate of the intermediate layer and outer layer at this peeled point were pulled in opposite directions using a tensile tester, so that the surface of the inner layer facing the intermediate layer and the surface of the intermediate layer facing the inner layer formed an angle of 180°. The laminate of the inner layer and biaxially oriented polyethylene terephthalate film was peeled from the intermediate layer at a peel rate of 50 mm / min (180° peel). The peel strength at this time was then measured. Furthermore, the peel resistance of the laminate film was evaluated based on this peel strength according to the following criteria. The results are shown in Table 1. [Evaluation criteria] A: The peel strength is 16N / 15mm or more, and the laminated film has high peel resistance. B: The peel strength is 10 N / 15 mm or more and less than 16 N / 15 mm, and the peel resistance of the laminated film is good. C: The peel strength is 6 N / 15 mm or more and less than 10 N / 15 mm, and the peel resistance of the laminated film is insufficient. D: The peel strength is less than 6 N / 15 mm, and the peel resistance of the laminated film is poor.

[0151] <<Laminated Film Manufacturing and Evaluation>> [Example 2] The bHDPE (80 parts by mass), the hPP (10 parts by mass), and the PR (10 parts by mass) were mixed at room temperature to prepare a resin composition (22). A long laminate film (thickness 300 μm) having the structure shown in Fig. 1 was obtained by laminating an inner layer (thickness 45 μm), an intermediate layer (thickness 210 μm), and an outer layer (thickness 45 μm) in this order in the thickness direction in the same manner as in Example 1, except that this resin composition (22) was used instead of the resin composition (21). The inner layer, intermediate layer, and outer layer were all unstretched layers. This laminated film was evaluated in the same manner as in Example 1. The results are shown in Table 1.

[0152] [Example 3] The bHDPE (90 parts by mass) and the PR (10 parts by mass) were mixed at room temperature to prepare a resin composition (23). A long laminate film (thickness 300 μm) having the structure shown in Fig. 1 was obtained by laminating an inner layer (thickness 45 μm), an intermediate layer (thickness 210 μm), and an outer layer (thickness 45 μm) in this order in the thickness direction in the same manner as in Example 1, except that this resin composition (23) was used instead of the resin composition (21). The inner layer, intermediate layer, and outer layer were all unstretched layers. This laminated film was evaluated in the same manner as in Example 1. The results are shown in Table 1.

[0153] [Example 4] The bHDPE (90 parts by mass) and the hPP (10 parts by mass) were mixed at room temperature to prepare a resin composition (24). A long laminate film (thickness 300 μm) having the structure shown in Fig. 1 was obtained by laminating an inner layer (thickness 45 μm), an intermediate layer (thickness 210 μm), and an outer layer (thickness 45 μm) in this order in the thickness direction in the same manner as in Example 1, except that this resin composition (24) was used instead of the resin composition (21). The inner layer, intermediate layer, and outer layer were all unstretched layers. This laminated film was evaluated in the same manner as in Example 1. The results are shown in Table 1.

[0154] [Comparative Example 1] The bHDPE (65 parts by mass), the hPP (15 parts by mass), and the PR (20 parts by mass) were mixed at room temperature to prepare a resin composition (R21). Except for using this resin composition (R21) instead of the resin composition (21) and changing the co-extrusion conditions, a long laminate film (300 μm thick) was obtained in the same manner as in Example 1. The inner layer (15 μm thick), intermediate layer (270 μm thick), and outer layer (15 μm thick) were laminated in this order in the thickness direction. The inner layer, intermediate layer, and outer layer were all unstretched layers. This laminated film was evaluated in the same manner as in Example 1. The results are shown in Table 2.

[0155] Comparative Example 2 Except for changing the co-extrusion conditions, a long laminated film (thickness 300 μm) was obtained in the same manner as in Comparative Example 1. The inner layer (thickness 25 μm), intermediate layer (thickness 250 μm), and outer layer (thickness 25 μm) were laminated in this order in the thickness direction. The inner layer, intermediate layer, and outer layer were all unstretched layers. This laminated film was evaluated in the same manner as in Example 1. The results are shown in Table 2.

[0156] Comparative Example 3 The hPP was extrusion molded to obtain a long, unstretched monolayer film (thickness: 300 μm) made of hPP. This monolayer film was evaluated in the same manner as in Example 1. The results are shown in Table 2.

[0157] In Tables 1 and 2, the notation "-" in the "Components and Contents (Parts by Mass)" column means that the corresponding layer in the laminated film does not contain that component.

[0158] [Table 1]

[0159] [Table 2]

[0160] As is clear from the above results, the laminated films of Examples 1 to 4 contained biomass-derived resin (bHDPE), and could be used as PTP base materials with high shape retention in the recesses, making it easy to remove stored contents. In Examples 1 to 4, the buckling strength of the recessed portion of the test piece was 11 to 15N.

[0161] In Examples 1 to 4, the tensile strength ratio of the laminated film was 1.1, and the molded product of the laminated film had high thickness uniformity in two directions of the recesses. Furthermore, in Examples 1 to 4, the Young's modulus of the laminated film was 1150 MPa or more (1150 to 1300 MPa), and the punching properties during molding of the laminated film were high.

[0162] Furthermore, in the laminate films of Examples 1 to 4, the peel strength between the inner layer and the intermediate layer was 14 N / 15 mm or more (14 to 18 N / 15 mm), and the peel resistance of the laminate films was good. In Examples 1 to 4, the thickness of the inner layer was 45 μm. In particular, in the laminate films of Examples 1 and 2, the peel strength between the inner layer and the intermediate layer was 17 N / 15 mm or more (17 to 18 N / 15 mm), and the peel resistance of the laminate films was particularly high.

[0163] Comparisons between Examples 1 and 3, and between Examples 2 and 4, suggest that increasing the content of petroleum resin in the intermediate layer increases the peel strength between the inner layer and the intermediate layer. Comparisons between Examples 3 and 4, and between Examples 1 and 2, suggest that increasing the content of the propylene-based polymer in the intermediate layer increases the peel strength between the inner layer and the intermediate layer, and that this effect is greater than in the case of petroleum resin. In Examples 1 and 2, the total content of the propylene-based polymer and petroleum resin in the intermediate layer was higher than in Examples 3 and 4, which was consistent with the fact that the peel strength was particularly high in the laminated films of Examples 1 and 2.

[0164] As described above, the laminated films of Examples 1 to 4 not only had high shape retention of the recesses when used as the base material of a PTP, but also had good properties related to three physical properties, namely, tensile strength ratio, Young's modulus, and peel strength between the inner layer and the middle layer, making them particularly preferable.

[0165] In Example 1, C X =90×0.15+10×0.15=15(mass parts), C Y =80×0.7+20×0.7=70(mass parts), C Z =90×0.15+10×0.15=15(mass parts), C W = 0 (parts by mass), and C V = 15 + 70 + 15 = 100 (parts by mass), and C Yb = 80 × 0.7 = 56 (parts by mass), and C Vb = 56 / 100 × 100 = 56% by mass. As a result of similar calculations, in Examples 2 to 4, C Vb was 56% by mass. That is, the laminated films of Examples 1 to 4 were particularly preferable as environmentally friendly resin films.

[0166] In contrast, although the laminated films of Comparative Examples 1 and 2 contained biomass-derived resin (bHDPE), it was not possible to manufacture a PTP base material with high shape retention of the recesses. In Comparative Examples 1 and 2, the buckling strength of the recessed portion of the test piece was 9 to 10N.

[0167] In Comparative Example 1, the tensile strength ratio of the laminated film was 1.4, and the molded product of the laminated film had low thickness uniformity in two directions of the recesses. Furthermore, in Comparative Examples 1 and 2, the Young's modulus of the laminated film was 950 MPa or less (850 to 950 MPa), and the punching properties of the laminated film during molding were poor. Furthermore, in the laminate films of Comparative Examples 1 and 2, the peel strength between the inner layer and the intermediate layer was 9 N / 15 mm or less (8 to 9 N / 15 mm), and the peel resistance of the laminate films was insufficient.In Comparative Examples 1 and 2, the thickness of the inner layer was 25 μm or less (15 to 25 μm).

[0168] The monolayer film of Comparative Example 3 did not contain any biomass-derived resin. [Industrial Applicability]

[0169] The present invention can be used to manufacture PTPs that contain biomass-derived resins and have recesses in the base material that retain their shape well. [Explanation of symbols]

[0170] 1. Laminated film 11. Inner layer 12. Middle class 13...outer layer 8...Lid material 9...Bottom material 91....Concave part of base material 101...Packaging

Claims

1. A laminated film configured by laminating an inner layer, an intermediate layer, and an outer layer in this order in the thickness direction, the inner layer and the outer layer contain a propylene-based polymer, the intermediate layer comprises biomass-derived polyethylene; A test piece was prepared in the laminated film, having a recess recessed in the thickness direction thereof, the opening of the recess having an inner diameter of 10 mm and a depth of 5 mm, A laminated film, wherein the buckling strength of the recess is 11 to 20 N.

2. 2. The laminate film according to claim 1, wherein, when the tensile strength of the laminate film is measured in accordance with JIS K 7127:1999, the tensile strength ratio of [tensile strength in MD of the laminate film] / [tensile strength in TD of the laminate film] is 1 to 1.

3.

3. The laminate film according to claim 1 or 2, wherein the Young's modulus of the laminate film measured in accordance with JIS K 7161-1:2014 is 1000 MPa or more.

4. 3. The laminate film according to claim 1, wherein a 15 mm wide test piece obtained by dry laminating the inner layer in the laminate film and a biaxially oriented polyethylene terephthalate film with a urethane adhesive is used, and when the laminate of the inner layer and the biaxially oriented polyethylene terephthalate film is peeled from the intermediate layer at a peel rate of 50 mm / min so that the surface of the inner layer facing the intermediate layer forms an angle of 180° with the surface of the intermediate layer facing the inner layer in the test piece, the measured peel strength is 10 N / 15 mm or more.

5. A packaging body constructed using the laminated film according to claim 1 or 2.

6. The packaging body comprises a lid material and a base material, The packaging body is formed by sealing the lid material and the base material, The packaging body according to claim 5 , wherein the base material is formed using the laminated film.

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