Resin film and packaging body

Abstract

Provided is a resin film for a bottom material of a blister pack packaging body. The resin film comprises: a base material layer; and a sealant layer provided on one surface of the base material layer. The base material layer contains a propylene-based resin. The sealant layer contains a homopolypropylene and an α-olefin elastomer. In the sealant layer, the proportion of the content of the homopolypropylene to the total mass of the sealant layer is at least 50 mass%. In the sealant layer, the proportion of the content of the α-olefin elastomer to the total mass of the sealant layer is at least 20 mass%.

Description

Resin film and packaging body

[0001] The present invention relates to a resin film and a packaging body. This application claims priority based on Japanese Patent Application No. 2025-004680 filed in Japan on January 14, 2025, and the contents thereof are incorporated herein by reference.

[0002] A blister pack packaging body (also referred to as a press-through package (PTP)) is composed of a heat seal between a bottom material provided with a recess and a sheet-like lid material, and the inside of the recess serves as a storage part, and it is mainly used for packaging tablets. In such a blister pack packaging body, a molded body of a transparent resin film is used as the bottom material, and an aluminum sheet is usually used as the lid material.

[0003] In recent years, methods for reusing (recycling) packaging bodies manufactured using resin films have been actively studied. For example, in the case of a resin film composed of multiple layers, if the main constituent materials of the resin layers of the multiple layers are of the same or similar types, there is no need to separate each resin layer and reuse them separately, and the entire resin film can be easily reused. Therefore, the development of such resin films composed of multiple layers has been actively promoted (see Patent Document 1).

[0004] Japanese Patent Application Laid-Open No. 2023-172392

[0005] Further, if the lid material is a resin film containing a resin of the same or similar type as the resin contained in the bottom material as the main constituent material instead of the conventional aluminum sheet, the lid material and the bottom material can be reused simultaneously, so the reusability of the blister pack packaging body becomes extremely high. And as the resin constituting the bottom material and the lid material, for example, propylene-based resins such as homopolypropylene and propylene copolymers can be used.

[0006] However, when using a lid material and a bottom material containing a propylene-based resin, there is a problem that the seal strength of the lid material and the bottom material becomes low.

[0007] The present invention aims to provide a resin film for manufacturing the bottom material of a blister pack packaging, which can achieve high sealing strength by heat sealing the bottom material and lid material containing a propylene resin.

[0008] To solve the above problems, the present invention adopts the following configuration: [1] A resin film for use as a bottom material for a blister pack packaging, wherein the resin film comprises a base layer and a sealant layer provided on one surface of the base layer, wherein the base layer contains a propylene resin, the sealant layer contains homopolypropylene and an α-olefin elastomer, the ratio of the content of homopolypropylene to the total mass of the sealant layer is 50% by mass or more, and the ratio of the content of the α-olefin elastomer to the total mass of the sealant layer is 20% by mass or more. [2] The resin film according to [1], wherein the sealant layer further contains an ethylene-vinyl acetate copolymer, and the ratio of the content of the ethylene-vinyl acetate copolymer to the total mass of the sealant layer is 10% by mass or more. [3] The resin film according to [1] or [2], wherein the base layer comprises homopolypropylene or a homopolypropylene and propylene copolymer as the propylene resin, and in the base layer, the ratio of the homopolypropylene content to the total mass of the base layer is 70 to 100% by mass, and in the base layer, the ratio of the propylene copolymer content to the total mass of the base layer is 0 to 30% by mass.

[0009] [4] The resin film according to any one of [1] to [3], wherein the sealant layer contains a propylene elastomer as the α-olefin elastomer, and in the sealant layer, the ratio of the total content of the homopolypropylene and the propylene elastomer to the total mass of the sealant layer is 80% by mass or more. [5] The resin film according to any one of [2] to [4], wherein the ratio of the content of the ethylene-vinyl acetate copolymer to the total mass of the sealant layer is 40% by mass or less. [6] The resin film according to any one of [1] to [5], wherein the ratio of the content of the propylene resin to the total mass of the base layer is 80% by mass or more. [7] The resin film according to any one of [1] to [6], wherein the base layer contains homopolypropylene and polypropylene random copolymer as the propylene resin, and in the base layer, the ratio of the total content of the homopolypropylene and polypropylene random copolymer to the total mass of the base layer is 80% by mass or more. [8] The resin film according to any one of [1] to [7], wherein the resin film comprises an outer layer provided on the other surface of the base layer, and the outer layer comprises homopolypropylene and an α-olefin elastomer. [9] The resin film according to [8], wherein the outer layer is identical to the sealant layer in terms of its composition and thickness.

[0010]

[10] A packaging body made using a resin film as described in any one of [1] to [9].

[11] The packaging body according to

[10] , wherein the packaging body is a blister pack packaging body composed of a lid material and a bottom material seal, wherein the bottom material is a molded body of the resin film, and the lid material contains a propylene resin.

[12] The packaging body according to

[11] , wherein the lid material comprises a second base material layer and a second sealant layer provided on one surface of the second base material layer, wherein the second sealant layer and the second base material layer contain the propylene resin, wherein in the second sealant layer, the ratio of the content of the propylene resin to the total mass of the second sealant layer is 80% by mass or more, and in the second base material layer, the ratio of the content of the propylene resin to the total mass of the second base material layer is 80% by mass or more.

[0011] According to the present invention, a resin film for manufacturing the bottom material of a blister pack packaging is provided, which provides high sealing strength when the bottom material and lid material containing a propylene resin are heat-sealed.

[0012] This is a schematic cross-sectional view showing an example of a resin film according to one embodiment of the present invention. This is a schematic perspective view showing an example of a package according to one embodiment of the present invention. This is a cross-sectional view of the package shown in Figure 2 along the line III-III.

[0013] <<Resin Film>> A resin film according to one embodiment of the present invention (which may be referred to as "resin film for bottom material" in this specification) is a resin film for use as a bottom material for a blister pack packaging, wherein the resin film comprises a base layer and a sealant layer provided on one surface of the base layer, wherein the base layer contains a propylene resin, and the sealant layer contains homopolypropylene and an α-olefin elastomer, wherein the content of homopolypropylene in the sealant layer is 50% by mass or more of the total mass of the sealant layer, and the content of α-olefin elastomer in the sealant layer is 20% by mass or more of the total mass of the sealant layer.

[0014] In the resin film of this embodiment, the sealant layer has a specific composition range as described above, and by heat sealing the bottom material manufactured by heat molding of the resin film of this embodiment with the lid material containing a propylene resin, a blister pack packaging body with high sealing strength can be obtained.

[0015] In the resin film of this embodiment, the base layer contains a propylene-based resin, and the sealant layer contains homopolypropylene. The α-olefin elastomer contained in the sealant layer may also be selected to have structural units derived from propylene. Therefore, by heat sealing the bottom material obtained from the resin film of this embodiment and the lid material containing a propylene-based resin, a package (for example, a blister pack package) can be manufactured that is made of a common resin, a propylene-based resin having structural units derived from propylene. In this specification, this process of constructing the entire package from a common resin is referred to as "monomaterialization."

[0016] In this specification, unless otherwise specified, the term "resin film" refers to the resin film of this embodiment.

[0017] The present invention will be described below with reference to the drawings. For convenience, the drawings used in the following description may show enlarged versions of key parts to make the features of the present invention easier to understand, and the dimensional ratios of each component may not be the same as in reality.

[0018] Figure 1 is a schematic cross-sectional view showing an example of a resin film according to this embodiment. The resin film 1 comprises a base layer 11 and a sealant layer 12 provided on one surface (sometimes referred to as the "first surface" in this specification) 11a of the base layer 11. The resin film 1 further comprises an outer layer 13 provided on the other surface 11b (sometimes referred to as the "second surface" in this specification) of the base layer 11. That is, the resin film 1 is constructed by laminating the sealant layer 12, the base layer 11, and the outer layer 13 in this order in the thickness direction. The resin film 1 is a resin film for manufacturing the bottom material of a blister pack packaging.

[0019] The base layer 11 contains a propylene resin. The sealant layer 12 contains homopolypropylene (hPP) and α-olefin elastomer (TPO). In the sealant layer 12, the proportion of homopolypropylene relative to the total mass of the sealant layer 12 is 50% by mass or more. In the sealant layer 12, the proportion of α-olefin elastomer relative to the total mass of the sealant layer is 20% by mass or more.

[0020] In the resin film 1, the sealant layer 12 is one outermost layer, and the outer layer 13 is the other outermost layer. In this specification, the outermost layer of the resin film means the outermost layer in the lamination direction of each layer constituting the resin film, and the outermost surface of the resin film, as described later, means the outermost surface (i.e., exposed surface) in the lamination direction of each layer constituting the resin film.

[0021] One surface of the sealant layer 12 (sometimes referred to as the "first surface" in this specification) 12a is the same as one surface of the resin film 1 (sometimes referred to as the "first surface" in this specification) 1a, and is the outermost surface and exposed surface. One surface of the outer layer 13 (sometimes referred to as the "second surface" in this specification) 13b is the same as the other surface of the resin film 1 (sometimes referred to as the "second surface" in this specification) 1b, and is the outermost surface and exposed surface. The first surface 1a of the resin film 1 is the sealing surface when the package is manufactured by heat sealing with the lid material described later, and the second surface 1b of the resin film 1 becomes the exposed surface of the resulting package.

[0022] In the resin film 1, the base layer 11 and the sealant layer 12 are essential components, but the outer layer 13 is an optional component, and the resin film 1 does not need to have an outer layer 13. In the resin film 1, the base layer 11 can also function as an outer layer.

[0023] The resin film of this embodiment is not limited to that shown in Figure 1, and some components of the film shown in Figure 1 may be modified, deleted, or added without departing from the spirit of the present invention. For example, as described above, the resin film of this embodiment does not have an outer layer. The resin film of this embodiment may or may not have other layers that do not fall under the categories of base layer, sealant layer, or outer layer. However, it is preferable that the resin film of this embodiment does not have the other layer on at least one surface (first surface, exposed surface) of the sealant layer, and it is preferable that there is no other layer between the base layer and the sealant layer. Each layer in the resin film of this embodiment will be described in more detail below.

[0024] <Sealant Layer> The sealant layer enables heat sealing of the resin film or its molded body (e.g., bottom material) with other resin films or their molded bodies (e.g., lid material). The sealant layer comprises homopolypropylene and an α-olefin elastomer, and may or may not further contain ethylene-vinyl acetate copolymer (EVA). Furthermore, the sealant layer may or may not contain other components that do not fall under homopolypropylene, α-olefin elastomer, or ethylene-vinyl acetate copolymer.

[0025] The homopolypropylene, α-olefin elastomer, ethylene-vinyl acetate copolymer, and the other components contained in the sealant layer may each be one or more, and if there are two or more, their combinations and ratios can be arbitrarily selected according to the purpose.

[0026] In the sealant layer, the ratio of the total content of all components of the sealant layer (homopolypropylene, α-olefin elastomer, ethylene-vinyl acetate copolymer, and the other components) to the total mass of the sealant layer does not exceed 100% by mass. Similarly, in the resin composition for forming the sealant layer, as described later, the ratio of the total content of all components of the resin composition to the total mass of the resin composition does not exceed 100% by mass.

[0027] The melt flow rate (MFR) of the homopolypropylene (hPP) contained in the sealant layer (sometimes referred to as "MFR" in this specification) is preferably 0.5 to 15 g / 10 min, and may be, for example, 0.5 to 6 g / 10 min, 4 to 11 g / 10 min, or 9 to 15 g / 10 min. Having the MFR of homopolypropylene within this range increases the sealing strength of the bottom material and lid material, and allows the resin film to be molded into the desired shape with high precision, resulting in improved moldability.

[0028] In this specification, MFR refers to the value measured in accordance with JIS K 7210-1:2014, not limited to homopolypropylene. The MFR of homopolypropylene is preferably the value obtained when the test temperature is 230°C.

[0029] For the same reasons as in the case of MFR described above, the melting point of the homopolypropylene contained in the sealant layer is preferably 155 to 162°C.

[0030] The aforementioned α-olefin-based elastomer (α-olefin-based thermoplastic elastomer) is not particularly limited as long as it is a resin in which an α-olefin polymer such as polypropylene (PP) or polyethylene (PE) is used as the hard segment and a rubber component such as ethylene propylene thermopolymer (ethylene propylene terpolymer, EPM) or ethylene propylene rubber (EPDM) is used as the soft segment. In this specification, an α-olefin-based elastomer with polypropylene as the hard segment may be referred to as a "propylene-based elastomer," and an α-olefin-based elastomer with polyethylene as the hard segment may be referred to as an "ethylene-based elastomer."

[0031] In terms of facilitating the monomaterialization of the resin film and packaging, it is preferable that the α-olefin elastomer is a propylene elastomer.

[0032] The bottom material of the blister pack packaging described later is manufactured by heat molding of a resin film. In this process, an auxiliary mold called a plug is pressed against the heated resin film to form a recess. However, if the resin film contains propylene-based resin, the bottom material may stick to the plug, making it impossible to mold properly. For example, after forming a recess, if the plug is moved away from the bottom surface of the recess in the depth direction of the recess in order to remove it, the bottom surface of the recess may move with the plug because it is stuck to the plug, resulting in a shallower recess. In contrast, in the sealant layer of the resin film of this embodiment, the content of homopolypropylene relative to the total mass of the sealant layer is 50% by mass or more. This suppresses the adhesion of the bottom material's recess to the plug, and tends to allow for the normal and reproducible formation of the recess. In this specification, this characteristic of being able to form a recess normally using a plug without the recess becoming shallow is specifically referred to as "plug moldability." Furthermore, the characteristic that allows for the high-precision realization of the desired shape in a recess, other than the depth of the recess, is simply referred to as "moldability."

[0033] In order to further improve the plug moldability of the above resin film, the ratio of homopolypropylene content to the total mass of the sealant layer may be, for example, 55% by mass or more, 60% by mass or more, 65% by mass or more, and 75% by mass or more. On the other hand, because the sealant layer contains an α-olefin elastomer, the above ratio is 80% by mass or less. In one embodiment, the above ratio may be, for example, 50-80% by mass, 55-80% by mass, 60-80% by mass, 65-80% by mass, and 75-80% by mass. However, these are just examples of the above ratios.

[0034] In the sealant layer, the proportion of α-olefin elastomer content relative to the total mass of the sealant layer is 20% by mass or more, which increases the sealing strength of the bottom material and lid material. To further enhance this effect, the proportion may be, for example, 25% by mass or more. On the other hand, because the sealant layer contains homopolypropylene, the proportion may be 50% by mass or less, for example, 45% by mass or less, 35% by mass or less, and 25% by mass or less. In one embodiment, the proportion may be, for example, 20-50% by mass, 20-45% by mass, 20-35% by mass and 20-25% by mass, or 25-50% by mass, 25-45% by mass and 25-35% by mass. However, these are just examples of the proportions.

[0035] When the sealant layer further contains an ethylene-vinyl acetate copolymer, in the blister pack packaging described later, when the lid material is peeled off the bottom material, a clear seal mark tends to be visible over the entire or a wide area of ​​the peeled surface of the bottom material (in other words, the surface of the bottom material that was sealed with the lid material). The seal mark present on the peeled surface of the bottom material is formed by the transfer of irregularities formed on the surface of the pressing means, such as a roll used to pressurize the bottom material and the lid material during heat sealing. Normally, when using blister pack packaging, it is not necessary to peel the lid material off the bottom material, but sometimes the lid material is intentionally peeled off from the bottom material. In that case, a clear seal mark over the entire or a wide area of ​​the peeled surface of the bottom material is preferable for appearance.

[0036] The melt flow rate (MFR) of the ethylene-vinyl acetate copolymer contained in the sealant layer is preferably 0.2 to 20 g / 10 min, and may be, for example, 0.2 to 15 g / 10 min, 0.2 to 10 g / 10 min, or 0.2 to 5 g / 10 min. Having the MFR of the ethylene-vinyl acetate copolymer within this range enhances the effects obtained by using the ethylene-vinyl acetate copolymer. The MFR of the ethylene-vinyl acetate copolymer is preferably the value obtained when the test temperature is 190°C.

[0037] The melting point of the ethylene-vinyl acetate copolymer contained in the sealant layer is preferably 47 to 96°C, and may be any of, for example, 58 to 96°C, 70 to 96°C, or 82 to 96°C. Having the melting point of the ethylene-vinyl acetate copolymer within this range enhances the effects obtained by using the ethylene-vinyl acetate copolymer.

[0038] In the ethylene-vinyl acetate copolymer contained in the sealant layer, the ratio of the amount of constituent units derived from vinyl acetate (parts by mass) to the total amount (parts by mass) of constituent units in the ethylene-vinyl acetate copolymer (sometimes referred to as "vinyl acetate content" in this specification) is preferably 10 to 30% by mass. Having a vinyl acetate content within this range enhances the effects obtained by using the ethylene-vinyl acetate copolymer.

[0039] When the sealant layer contains an ethylene-vinyl acetate copolymer, the ratio of the ethylene-vinyl acetate copolymer content to the total mass of the sealant layer is preferably 10% by mass or more, for example, 13% by mass or more, or 17% by mass or more. When the ratio is above the lower limit, the appearance of the peeled surface of the bottom material is improved. On the other hand, the ratio is preferably 40% by mass or less, in that it provides a good balance between the effect of increasing the seal strength of the bottom material and the lid material and the effect of improving the appearance of the peeled surface of the bottom material, and facilitates the monomaterialization of the resin film and the packaging body. In one embodiment, the ratio may be, for example, 10 to 40% by mass, 13 to 40% by mass, or 17 to 40% by mass. However, these are just examples of the ratios.

[0040] The other components included in the sealant layer may be either resin components or non-resin components.

[0041] Of the other components mentioned above, the resin component is not particularly limited as long as it does not fall under any of homopolypropylene, α-olefin elastomer, or ethylene-vinyl acetate copolymer.

[0042] Among the other components mentioned above, the non-resin component may include, for example, additives known in the art. Examples of such additives include antifogging agents, antiblocking agents, antioxidants, antistatic agents, nucleating agents, inorganic particles, viscosity reducers, viscosity thickeners, heat stabilizers, lubricants, infrared absorbers, ultraviolet absorbers, and colorants (e.g., dyes, pigments, etc.).

[0043] In the sealant layer, the ratio of the total content of homopolypropylene, an α-olefin-based elastomer, and an ethylene-vinyl acetate copolymer to the total mass of the sealant layer (([the content of homopolypropylene in the sealant layer (parts by mass)] + [the content of the α-olefin-based elastomer in the sealant layer (parts by mass)] + [the content of the ethylene-vinyl acetate copolymer in the sealant layer (parts by mass)]) / [the total mass of the sealant layer (parts by mass)] × 100) is preferably 80% by mass or more, and may be, for example, any one of 85% by mass or more, 90% by mass or more, 95% by mass or more, and 98% by mass or more. When the ratio is at least the lower limit value, the effects obtained by using these resins become higher. On the other hand, the ratio is 100% by mass or less. Here, for example, when the sealant layer does not contain an ethylene-vinyl acetate copolymer, the content of the ethylene-vinyl acetate copolymer in the sealant layer is 0 parts by mass. The ratio is usually the same as the ratio of the total content of homopolypropylene, an α-olefin-based elastomer, and an ethylene-vinyl acetate copolymer to the total content (parts by mass) of components that do not vaporize at normal temperature in the resin composition described below (([the content of homopolypropylene in the resin composition (parts by mass)] + [the content of the α-olefin-based elastomer in the resin composition (parts by mass)] + [the content of the ethylene-vinyl acetate copolymer in the resin composition (parts by mass)]) / [the total content of components that do not vaporize at normal temperature in the resin composition (parts by mass)] × 100). The relationship between the content of the components contained in any layer constituting the resin film and the content of the components contained in the resin composition for forming this layer is the same for the layers other than the sealant layer, which will be described later.

[0044] In this specification, "normal temperature" means a temperature that is not particularly cooled or heated, that is, an ordinary temperature, and examples thereof include a temperature of 15 to 25°C.

[0045] Among the above-mentioned components contained in the sealant layer, resins that contribute to the monomerization of the resin film and the package formed using the same include homopolypropylene and propylene-based elastomers.

[0046] In terms of facilitating the monomerization of the resin film and the package, in the sealant layer, the ratio of the total content of homopolypropylene and propylene-based elastomer to the total mass of the sealant layer is preferably 60% by mass or more, and for example, it may be any one of 80% by mass or more, 90% by mass or more, 95% by mass or more, and 98% by mass or more. The higher the ratio, the easier it is to monomerize the resin film. On the other hand, the ratio is 100% by mass or less. Here, for example, when the sealant layer does not contain a propylene-based elastomer, the content of the propylene-based elastomer in the sealant layer is 0 parts by mass.

[0047] In terms of facilitating the monomerization of the resin film and the package, in the sealant layer, the ratio of the content of ethylene-vinyl acetate copolymer to the total mass of the sealant layer is preferably 40% by mass or less, and for example, it may be any one of 20% by mass or less, 10% by mass or less, 5% by mass or less, and 2% by mass or less. The lower the ratio, the easier it is to monomerize the resin film. On the other hand, the ratio is 0% by mass or more.

[0048] The sealant layer may be composed of one layer (single layer) or may be composed of two or more layers. When the sealant layer is composed of multiple layers, these multiple layers may be the same as or different from each other, and the combination of these multiple layers is not particularly limited as long as the effects of the present invention are not impaired. However, usually, a single-layer sealant layer is sufficient.

[0049] In this specification, not limited to the case of the sealant layer, "the multiple layers may be the same as or different from each other" means that "all the layers may be the same, all the layers may be different, or only some of the layers may be the same". Further, "the multiple layers are different from each other" means that "at least one of the constituent materials and thicknesses of each layer is different from each other".

[0050] The thickness of the sealant layer is not particularly limited, but is preferably 3 to 30 μm, more preferably 9 to 24 μm, and even more preferably 12 to 18 μm. When the thickness of the sealant layer is greater than or equal to the lower limit, the structure of the sealant layer is more stable, and the sealing strength of the bottom material and lid material is higher. When the thickness of the sealant layer is less than or equal to the upper limit, the thickness of the sealant layer is avoided, and the resin film can be made thinner. Here, "thickness of the sealant layer" means the total thickness of the sealant layer, and for example, the thickness of a sealant layer consisting of multiple layers means the total thickness of all the layers that make up the sealant layer. This is also true for layers other than the sealant layer, which will be described later.

[0051] <Base Layer> The base layer is the main layer of the resin film, enabling the resin film to maintain its structure stably and allowing the molded bottom material to constitute a blister pack. The base layer contains a propylene-based resin. The propylene-based resin contained in the base layer contributes to the monomaterialization of the resin film and the packaging body constructed using it. The base layer may or may not contain other components that are not propylene-based resin.

[0052] The propylene resin contained in the base layer and the other components may each be one type or two or more types, and if there are two or more types, their combination and ratio can be arbitrarily selected according to the purpose.

[0053] In the base layer, the ratio of the total content of all components of the base layer (propylene resin and the other components) to the total mass of the base layer does not exceed 100% by mass. Similarly, in the resin composition for forming the base layer, which will be described later, the ratio of the total content of all components of the resin composition to the total mass of the resin composition does not exceed 100% by mass.

[0054] The propylene-based resin contained in the base layer is not particularly limited as long as it is a resin having structural units derived from propylene. For example, it may be homopolypropylene (hPP), or a propylene-based copolymer having both structural units derived from propylene and structural units derived from monomers other than propylene. The higher the homopolypropylene content in the base layer, the more stable the structure of the resin film becomes, and the higher the propylene-based copolymer content in the base layer, the lower the molding temperature of the resin film can be, making it easier to mold the resin film.

[0055] Examples of homopolypropylene contained in the base layer include those similar to those contained in the sealant layer.

[0056] Examples of the propylene copolymer contained in the substrate layer include polypropylene random copolymers (rPP, propylene random copolymer) such as propylene-ethylene binary copolymer, propylene-1-butene-ethylene ternary copolymer, and propylene-1-butene binary copolymer; and polypropylene block copolymer (bPP, propylene block copolymer).

[0057] The melt flow rate (MFR) of the propylene copolymer contained in the base layer is preferably 0.5 to 15 g / 10 min, and may be, for example, 0.5 to 6 g / 10 min, 4 to 11 g / 10 min, or 9 to 15 g / 10 min. Having the MFR of the propylene copolymer within this range improves the moldability of the resin film.

[0058] For the same reasons as in the case of MFR described above, the melting point of the propylene copolymer contained in the substrate layer is preferably 125 to 155°C.

[0059] The base layer preferably contains either homopolypropylene or polypropylene random copolymer, or both, as the propylene-based resin. More preferably, it contains homopolypropylene but no propylene copolymer, or homopolypropylene and a propylene copolymer. Even more preferably, it contains homopolypropylene but no propylene copolymer, or homopolypropylene and a polypropylene random copolymer. A resin film with such a base layer does not require an excessively high molding temperature and can be easily molded.

[0060] The other components contained in the base layer may be either resin components or non-resin components.

[0061] Of the other components contained in the base layer, the resin component is not particularly limited as long as it is not a propylene-based resin. Examples of the non-resin components among the other components contained in the base layer include those similar to the non-resin components contained in the sealant layer described earlier.

[0062] In the base layer, the ratio of the propylene resin content to the total mass of the base layer is preferably 80% by mass or more, and may be, for example, 85% by mass or more, 90% by mass or more, 95% by mass or more, or 98% by mass or more. When the ratio is above the lower limit, the effects obtained by the base layer containing propylene resin are enhanced, and the monomaterialization of the resin film and packaging becomes easier. On the other hand, the ratio is 100% by mass or less. Here, "propylene resin content" refers to the total content of homopolypropylene and propylene copolymer. For example, if the base layer does not contain propylene copolymer, the propylene copolymer content of the base layer is 0 parts by mass.

[0063] A more preferable base layer, in that it enhances the effect of easily forming the resin film, is one in which the propylene resin contains homopolypropylene but does not contain a propylene copolymer, or contains homopolypropylene and a propylene copolymer, and in the base layer, the ratio of the homopolypropylene content to the total mass of the base layer is 70 to 100% by mass, and in the base layer, the ratio of the propylene copolymer content to the total mass of the base layer is 0 to 30% by mass.

[0064] A more preferable base layer, in that it further enhances the effect of easily forming the resin film, is one in which the propylene resin contains homopolypropylene but does not contain a propylene copolymer, or contains homopolypropylene and a polypropylene random copolymer, and in the base layer, the ratio of the homopolypropylene content to the total mass of the base layer is 70 to 100% by mass, and in the base layer, the ratio of the polypropylene random copolymer content to the total mass of the base layer is 0 to 30% by mass.

[0065] In a substrate layer containing homopolypropylene and potentially polypropylene random copolymer, the ratio of the total content of homopolypropylene and polypropylene random copolymer to the total mass of the substrate layer is preferably 80% by mass or more, for example, 85% by mass or more, 90% by mass or more, 95% by mass or more, and 98% by mass or more. The higher the ratio, the greater the effect obtained by using these resins. On the other hand, the ratio is 100% by mass or less. Here, for example, if the substrate layer does not contain polypropylene random copolymer, the content of polypropylene random copolymer in the substrate layer is 0 parts by mass.

[0066] The base layer may consist of one layer (single layer) or of two or more layers. When the base layer consists of multiple layers, these layers may be identical or different, and the combination of these layers is not particularly limited as long as it does not impair the effects of the present invention. However, usually, a single base layer is sufficient.

[0067] The thickness of the base layer is not particularly limited, but is preferably 220 to 297 μm, more preferably 226 to 291 μm, and even more preferably 232 to 288 μm. When the thickness of the base layer is above the lower limit, the structure of the base layer becomes more stable. When the thickness of the base layer is below the upper limit, the thickness of the base layer is avoided, and the resin film can be made thinner.

[0068] <Outer layer> The outer layer protects the structure on the sealant layer side of the resin film or its molded body from the outer layer. The outer layer may also be easier to form the printed layer corresponding to the other layers than the base layer.

[0069] In terms of improving the properties of the resin film as a bottom material for blister pack packaging, it is preferable that the components of the outer layer are the same as those of the sealant layer. For example, the components of the outer layer and their content (i.e., composition) may be the same as those of the sealant layer.

[0070] In the outer layer, the ratio of the total content of all components of the outer layer (e.g., homopolypropylene, α-olefin elastomer, ethylene-vinyl acetate copolymer, and the other components) to the total mass of the outer layer does not exceed 100% by mass. Similarly, in the resin composition for forming the outer layer, which will be described later, the ratio of the total content of all components of the resin composition to the total mass of the resin composition does not exceed 100% by mass.

[0071] For example, the outer layer may contain homopolypropylene and an α-olefin elastomer, and may or may not contain an ethylene-vinyl acetate copolymer (EVA). The outer layer may or may not contain other components that do not fall under any of homopolypropylene, α-olefin elastomer, or ethylene-vinyl acetate copolymer. In terms of facilitating the monomaterialization of the resin film and packaging, the α-olefin elastomer contained in the outer layer is preferably a propylene elastomer.

[0072] For example, in the outer layer, the ratio of homopolypropylene content to the total mass of the outer layer may be 50% by mass or more, 55% by mass or more, 60% by mass or more, 65% by mass or more, and 75% by mass or more, and may be 80% by mass or less. In one embodiment, the ratio may be, for example, 50 to 80% by mass, 55 to 80% by mass, 60 to 80% by mass, 65 to 80% by mass, and 75 to 80% by mass.

[0073] For example, in the outer layer, the ratio of the α-olefin elastomer content to the total mass of the outer layer may be 20% by mass or more, 25% by mass or more, or 50% by mass or less, 45% by mass or less, 35% by mass or less, or 25% by mass or less. In one embodiment, the ratio may be, for example, 20 to 50% by mass, 20 to 45% by mass, 20 to 35% by mass, and 20 to 25% by mass, or 25 to 50% by mass, 25 to 45% by mass, and 25 to 35% by mass.

[0074] For example, if the outer layer contains an ethylene-vinyl acetate copolymer, the ratio of the ethylene-vinyl acetate copolymer content to the total mass of the outer layer may be 10% by mass or more, 13% by mass or more, and 17% by mass or more, or 40% by mass or less. In one embodiment, the ratio may be, for example, 10 to 40% by mass, 13 to 40% by mass, and 17 to 40% by mass.

[0075] The other components contained in the outer layer may be the same as the other components contained in the sealant layer.

[0076] For example, in the outer layer, the total content ratio of homopolypropylene, α-olefin elastomer, and ethylene-vinyl acetate copolymer relative to the total mass of the outer layer may be 80% by mass or more, 85% by mass or more, 90% by mass or more, 95% by mass or more, and 98% by mass or more, while the ratio may be 100% by mass or less.

[0077] For example, among the components of the outer layer mentioned above, homopolypropylene and propylene-based elastomers are examples of resins that contribute to the monomaterialization of the resin film and the packaging body constructed using it.

[0078] For example, in terms of facilitating the monomaterialization of the resin film and packaging, the ratio of the total content of homopolypropylene and propylene-based elastomer relative to the total mass of the outer layer may be 80% by mass or more, 85% by mass or more, 90% by mass or more, 95% by mass or more, and 98% by mass or more, while the ratio may be 100% by mass or less.

[0079] For example, in terms of facilitating the monomaterialization of the resin film and packaging, the ratio of the ethylene-vinyl acetate copolymer content to the total mass of the outer layer may be 40% by mass or less, 20% by mass or less, 10% by mass or less, 5% by mass or less, and 2% by mass or less, while the ratio may be 0% by mass or more.

[0080] Further detailed explanation of the composition of the outer layer will be omitted.

[0081] The outer layer may consist of one layer (single layer) or of two or more layers. If the outer layer consists of multiple layers, these layers may be identical or different, and the combination of these layers is not particularly limited as long as it does not impair the effects of the present invention. However, usually, a single outer layer is sufficient.

[0082] The thickness of the outer layer is not particularly limited, but is preferably 3 to 30 μm, more preferably 9 to 24 μm, and even more preferably 12 to 18 μm. When the thickness of the outer layer is above the lower limit, the structure of the outer layer becomes more stable. When the thickness of the outer layer is below the upper limit, the thickness of the outer layer is avoided, and the resin film can be made thinner.

[0083] In terms of improving the properties of the aforementioned resin film, it is preferable that the outer layer is identical to the sealant layer in terms of its composition and thickness. Such a resin film, for example, has a high curl-suppression effect.

[0084] <Other Layers> The other layers provided in the resin film can be arbitrarily selected according to the purpose and are not particularly limited. For example, they may be a resin layer (a layer containing resin) or a non-resin layer (a layer not containing resin). However, in terms of facilitating the monomaterialization of the base material and the packaging, it is preferable that the ratio of the propylene resin content to the total mass of the other layers is 50 to 100% by mass. The thickness of the other layers provided in the resin film can also be arbitrarily selected according to the purpose and is not particularly limited. The other layers provided in the resin film may consist of one layer (single layer) or two or more layers. If there are multiple layers, these layers may be the same or different from each other, and the combination of these layers is not particularly limited as long as it does not impair the effects of the present invention.

[0085] <Other components of the resin film> The thickness of the resin film is not particularly limited, but is preferably 200 to 350 μm, more preferably 225 to 325 μm, and even more preferably 285 to 315 μm. When the thickness of the resin film is above the lower limit, the structure of the resin film becomes more stable. When the thickness of the resin film is below the upper limit, the thickness of the resin film is avoided, and the bottom material described later can be made thinner.

[0086] The resin film is preferably an unoriented film. An unoriented resin film has higher moldability.

[0087] <Example of a resin film> An example of a preferred resin film of this embodiment is a resin film for use as a bottom material for a blister pack packaging, wherein the resin film comprises a base layer and a sealant layer provided on one surface of the base layer, wherein the base layer contains a propylene-based resin, the sealant layer contains homopolypropylene and an α-olefin-based elastomer, the ratio of the homopolypropylene content to the total mass of the sealant layer is 50% by mass or more, the ratio of the α-olefin-based elastomer content to the total mass of the sealant layer is 20% by mass or more, the sealant layer may or may not contain an ethylene-vinyl acetate copolymer, if the sealant layer contains the ethylene-vinyl acetate copolymer, the ratio of the ethylene-vinyl acetate copolymer content to the total mass of the sealant layer is 10% by mass or more, and the base layer contains homopolypropylene or a homopolypropylene and propylene-based copolymer as the propylene-based resin. A resin film is provided in which the content of homopolypropylene in the base layer is 70 to 100% by mass relative to the total mass of the base layer, and the content of propylene copolymer in the base layer is 0 to 30% by mass relative to the total mass of the base layer.

[0088] In the sealant layer of such a resin film, it is preferable that the total content ratio of the homopolypropylene, the α-olefin elastomer, and the ethylene-vinyl acetate copolymer to the total mass of the sealant layer is 80% by mass or more. In the sealant layer of such a resin film, it is preferable that the content ratio of the ethylene-vinyl acetate copolymer to the total mass of the sealant layer is 40% by mass or less. In the base layer of such a resin film, it is preferable that the content ratio of the propylene resin to the total mass of the base layer is 80% by mass or more. Such a resin film may further include an outer layer provided on the side of the base layer opposite to the side of the sealant layer (the other side or second side), the composition of the outer layer may be the same as the composition of the sealant layer, and the composition and thickness of the outer layer may be the same as the composition and thickness of the sealant layer.

[0089] <<Method for Manufacturing Resin Film>> The resin film of this embodiment can be manufactured, for example, by a feed block method in which several extruders are used to melt-extrude the resin or resin composition that will form each layer, a co-extrusion T-die method such as a multi-manifold method, or an air-cooled or water-cooled co-extrusion inflation method.

[0090] The resin composition that forms any of the layers in the resin film can be manufactured by adjusting the types and amounts of the constituent components so that the layer to be formed contains the desired components (constituent materials) in the desired amounts. For example, the ratio of the amounts of components that do not vaporize at room temperature in the resin composition is usually the same as the ratio of the amounts of those components in the layer formed from this resin composition.

[0091] Examples of resin compositions for forming a sealant layer (sealant layer forming composition) include a resin composition (S) comprising homopolypropylene, an α-olefin elastomer, an ethylene-vinyl acetate copolymer if necessary, and the aforementioned other components if necessary.

[0092] Examples of resin compositions for forming a base layer (base layer forming composition) include resin composition (B) which comprises a propylene resin and, if necessary, the other components.

[0093] Examples of resin compositions for forming the outer layer (outer layer forming composition) include those similar to the resin composition (S) described above.

[0094] When using the aforementioned resin composition, for example, a mixture of two or more components (dry blend, unmixed) may be directly fed into the extruder as the resin composition, or a pre-mixed mixture of two or more components may be fed into the extruder as the resin composition. The pre-mixed mixture can be obtained, for example, by melt-mixing two or more components using a twin-screw extruder or a Banbury mixer.

[0095] <<Packaging>> The packaging according to one embodiment of the present invention is constructed using the resin film according to the above embodiment of the present invention. The packaging of this embodiment is constructed by heat-sealing the resin film with another resin film or a molded product thereof.

[0096] A preferred example of packaging according to this embodiment is a blister pack packaging composed of a lid material and a bottom material seal, wherein the bottom material is a molded body of the resin film and the lid material contains a propylene resin. The lid material is preferably in the form of a film. In such a blister pack packaging, because the bottom material is a molded body of the resin film, the seal strength of the bottom material and the lid material is high, even if the lid material contains a propylene resin.

[0097] The seal strength of the bottom and lid materials of the blister pack packaging in this embodiment can be determined, for example, by the peel strength of the test specimen shown below. That is, a sealing speed of 11 m / min and a sealing pressure of 0.45 MPa (4.6 kgf / cm²). ２Under the conditions described above, the base material and lid material are heat-sealed, and a small piece with a width of 15 mm is cut from the area of ​​the base material where no recess is formed (flat area) of the resulting seal, and this piece is used as the test piece. Alternatively, under the same conditions as above, the resin film and lid material are heat-sealed, and a small piece with a width of 15 mm is cut from the resulting seal, and this piece is used as the test piece. Next, the lid material is peeled from the base material or the resin film at a peeling speed of 100 mm / min, from one end in the longitudinal direction of the test piece toward the other end (i.e., along the longitudinal direction of the test piece). The angle between the peeled surface of the base material or the resin film and the peeled surface of the lid material, i.e., the peeling angle, is set to 180°. The value in which the variation of the measured peeling strength during this period is suppressed is adopted as the seal strength (N / 15 mm) of the base material and lid material.

[0098] Up to this point, we have described the method for measuring peel strength using a test specimen with a width of 15 mm. However, test specimens with dimensions other than 15 mm in width may also be used. In that case, the peel strength obtained by measuring in the same manner as above may be multiplied by 15 (mm), and then divided by the width of the test specimen (mm) to obtain a converted value (calculated as [measured value of peel strength with a test specimen with dimensions other than 15 mm in width (N)] × 15 (mm) / [width of the test specimen (mm)]), which may be adopted as the sealing strength (N / 15 mm) of the bottom material and lid material.

[0099] The heat sealing temperature of the base material or the resin film and the lid material when preparing the test specimen can be selected according to the purpose, and may be the same as the heat sealing temperature of the base material and lid material in the packaging manufacturing method described later.

[0100] When the heat-seal temperature of the base material or the resin film and the lid material is 125°C, the seal strength of the base material and the lid material (which may be referred to as "125°C seal strength" in this specification) is preferably 6.5 N / 15 mm or more, and may be, for example, 8 N / 15 mm or more and 9.5 N / 15 mm or more. On the other hand, the upper limit of the 125°C seal strength is not particularly limited. For example, a package with a 125°C seal strength of 13 N / 15 mm or less can be more easily realized.

[0101] When the heat-seal temperature of the base material or the resin film and the lid material is 135°C, the seal strength of the base material and the lid material (which may be referred to as "135°C seal strength" in this specification) is preferably 8.5 N / 15 mm or more, and may be, for example, 10 N / 15 mm or more and 12 N / 15 mm or more. On the other hand, the upper limit of the 135°C seal strength is not particularly limited. For example, a package with a 135°C seal strength of 15 N / 15 mm or less can be more easily realized.

[0102] The sealing strength of the bottom material and lid material of the blister pack packaging of this embodiment (in other words, the peel strength of the test piece) can be adjusted, for example, by adjusting the type and content of the components contained in the layers that bond (heat seal) the bottom material and lid material together, as well as the thickness of the bonding layers.

[0103] Next, we will explain the lid and bottom materials in more detail.

[0104] <Lid Material> The lid material in the packaging body contains a propylene resin and may be referred to as a "resin film for lid material" in this specification. The lid material comprises a second base material layer and a second sealant layer provided on one surface of the second base material layer, and it is preferable that the second sealant layer and the second base material layer contain a propylene resin. In this specification, the term "base material layer" refers to the base material layer in the resin film and the bottom material, not the second base material layer in the lid material. Similarly, the term "sealant layer" refers to the sealant layer in the resin film and the bottom material, not the second sealant layer in the lid material.

[0105] The propylene-based resin contained in the second sealant layer and the second base layer contributes to the monomaterialization of the packaging. The second sealant layer and the second base layer may or may not contain other components that are not propylene-based resins.

[0106] The propylene resin contained in the second sealant layer and the second substrate layer, and the other components, may each consist of only one type or two or more types. If there are two or more types, their combination and ratio can be arbitrarily selected according to the purpose.

[0107] In the second base layer, the ratio of the total content of all components of the second base layer (e.g., propylene resin and the other components) to the total mass of the second base layer does not exceed 100% by mass. Similarly, in the resin composition for forming the second base layer, as described later, the ratio of the total content of all components of the resin composition to the total mass of the resin composition does not exceed 100% by mass. In the second sealant layer, the ratio of the total content of all components of the second sealant layer (e.g., propylene resin and the other components) to the total mass of the second sealant layer does not exceed 100% by mass. Similarly, in the resin composition for forming the second sealant layer, as described later, the ratio of the total content of all components of the resin composition to the total mass of the resin composition does not exceed 100% by mass.

[0108] Examples of the propylene-based resin contained in the second base material layer include those similar to the propylene-based resin contained in the base material layer in the resin film and the base material (homopolypropylene, propylene copolymer).

[0109] The propylene-based resin contained in the second sealant layer is the same as the propylene-based resin contained in the sealant layer in the resin film and the bottom material (homoplypropylene (hPP), α-olefin elastomer (TPO), ethylene-vinyl acetate copolymer (EVA)). In particular, in terms of achieving higher sealing strength of the bottom material and lid material, it is preferable that the second sealant layer contains α-olefin elastomer and ethylene-vinyl acetate copolymer as the propylene-based resin.

[0110] The other components included in the second sealant layer and the second substrate layer may be either resin components or non-resin components.

[0111] Of the other components contained in the second sealant layer and the second substrate layer, the resin component is not particularly limited as long as it is not a propylene-based resin. Of the other components contained in the second sealant layer and the second substrate layer, the non-resin component is, for example, the same as the non-resin component contained in the sealant layer in the resin film and the base material described above.

[0112] In the second sealant layer, the ratio of the propylene resin content to the total mass of the second sealant layer is preferably 80% by mass or more, and may be, for example, 85% by mass or more, 90% by mass or more, 95% by mass or more, or 98% by mass or more. When the ratio is above the lower limit, the effects obtained by including the propylene resin in the second sealant layer are enhanced, and the monomaterialization of the packaging becomes easier. On the other hand, the ratio is 100% by mass or less. Here, "propylene resin content" refers to the total content of homopolypropylene and propylene copolymer. For example, if the second sealant layer does not contain a propylene copolymer, the propylene copolymer content in the second sealant layer is 0 parts by mass.

[0113] In the second sealant layer, the ratio of the total content of α-olefin elastomer and ethylene-vinyl acetate copolymer to the total mass of the second sealant layer is preferably 80% by mass or more, for example, it may be 85% by mass or more, 90% by mass or more, 95% by mass or more, or 98% by mass or more. The effect obtained by using these resins is enhanced when the ratio is above the lower limit. On the other hand, the ratio is 100% by mass or less. Here, for example, if the second sealant layer does not contain either α-olefin elastomer or ethylene-vinyl acetate copolymer, the content of that component in the second sealant layer is 0 parts by mass.

[0114] When the second sealant layer contains an α-olefin elastomer and an ethylene-vinyl acetate copolymer, the mass ratio of [content of α-olefin elastomer (parts by mass)] / [content of ethylene-vinyl acetate copolymer (parts by mass)] in the second sealant layer is preferably 95 / 5 to 65 / 35, and may be, for example, 90 / 10 to 70 / 30 and 85 / 15 to 75 / 25. Having the mass ratio within this range increases the sealing strength of the bottom material and the lid material.

[0115] In the second base layer, the ratio of the propylene resin content to the total mass of the second base layer is preferably 80% by mass or more, and may be, for example, 85% by mass or more, 90% by mass or more, 95% by mass or more, or 98% by mass or more. When the ratio is above the lower limit, the effects obtained by the inclusion of the propylene resin in the second base layer are enhanced, and the monomaterialization of the packaging becomes easier. On the other hand, the ratio is 100% by mass or less. Here, "propylene resin content" is the same as in the case of the second sealant layer described above.

[0116] The second base layer preferably contains homopolypropylene as the propylene-based resin. A lid material equipped with such a second base layer has better properties.

[0117] When the second base layer contains homopolypropylene, the ratio of homopolypropylene content to the total mass of the second base layer is preferably 80% by mass or more, for example, 85% by mass or more, 90% by mass or more, 95% by mass or more, and 98% by mass or more. The higher the ratio, the greater the effect obtained by using homopolypropylene. On the other hand, the ratio is 100% by mass or less.

[0118] The second sealant layer and the second substrate layer may consist of one layer (single layer) or of two or more layers. When the second sealant layer or the second substrate layer consists of multiple layers, these layers may be identical or different, and the combination of these layers is not particularly limited as long as it does not impair the effects of the present invention. However, in most cases, it is sufficient for the second sealant layer and the second substrate layer to consist of one layer.

[0119] The thickness of the second sealant layer is not particularly limited, but is preferably 2 to 22 μm, and more preferably 3 to 20 μm. When the thickness of the second sealant layer is greater than or equal to the lower limit, the structure of the second sealant layer becomes more stable, and the sealing strength of the bottom material and lid material becomes higher. When the thickness of the second sealant layer is less than or equal to the upper limit, the thickness of the second sealant layer is avoided, and the lid material can be made thinner.

[0120] The thickness of the second base material layer is not particularly limited, but is preferably 28 to 92 μm, and more preferably 35 to 85 μm. When the thickness of the second base material layer is greater than or equal to the lower limit, the structure of the lid material is more stable. When the thickness of the second base material layer is less than or equal to the upper limit, the thickness of the lid material is not excessive, and for example, it becomes easier to remove the contents from the package.

[0121] The side of the lid material opposite to the side that is heat-sealed (for example, the side of the second base material layer opposite to the side of the second sealant layer, which may be referred to herein as the "non-sealing side") may or may not have other layers. It is preferable that at least the area of ​​the side of the lid material that is heat-sealed (for example, the side of the second sealant layer opposite to the side of the second base material layer) that is actually heat-sealed does not have the other layers.

[0122] The other layer provided on the non-sealing surface of the lid material may or may not be patterned, and may form letters.

[0123] Examples of other layers provided on the non-sealing surface of the lid material include a printed layer.

[0124] The thickness of the lid material (for example, the total thickness of the second sealant layer, the second base layer, and the other layers) is not particularly limited, but is preferably 30 to 105 μm, more preferably 33 to 102 μm, and even more preferably 38 to 98 μm. When the thickness of the lid material is above the lower limit, the structure of the lid material is more stable. When the thickness of the lid material is below the upper limit, the thickness of the lid material is avoided, and for example, it becomes easier to remove the contents of the package.

[0125] Examples of lid materials that are laminates of the second base material layer and the second sealant layer include those similar to the resin film 1 shown in Figure 1, in which the outer layer 13 is omitted.

[0126] <Bottom Material> The bottom material in the packaging is a heat-molded body of the resin film. The thickness of the bottom material in its flat portion may be, for example, the same as the thickness of the resin film described above.

[0127] Next, I will explain the overall structure of the packaging in detail.

[0128] Figure 2 is a schematic perspective view showing an example of the packaging of this embodiment. Figure 3 is a cross-sectional view of the packaging shown in Figure 2 along the line III-III. The packaging 101 shown here is a blister pack packaging and comprises a lid material 8 and a bottom material 9. The planar shape of the packaging 101 is rectangular. The lid material 8 preferably contains a propylene resin. The bottom material 9 is made using a resin film according to the above-described embodiment, and more specifically, is a molded body of the resin film.

[0129] The base material 9 has multiple recesses 91 that protrude from one side of the base material 9 (sometimes referred to as the "first side" in this specification) 9a and have openings on the other side of the base material 9 (sometimes referred to as the "second side" in this specification) 9b. In the packaging body 101, the base material 9 is positioned with its second side 9b facing the lid material 8, and the first side 9a of the base material 9 is one of the outermost surfaces (exposed surfaces) of the packaging body 101.

[0130] When the base material 9 is a molded body of the resin film 1 shown in Figure 1, the first surface 1a of the resin film 1 corresponds to the second surface 9b of the base material 9, and the second surface 1b of the resin film 1 corresponds to the first surface 9a of the base material 9.

[0131] One side of the lid material 8 (sometimes referred to as the "first side" in this specification) 8a 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 side (sometimes referred to as the "second side" in this specification) 8b facing the bottom material 9 side.

[0132] When the lid material 8 is a laminate of the second base layer and the second sealant layer described above, the side of the second sealant layer opposite to the second base layer corresponds to the second surface 8b of the lid material 8, and the side of the second base layer opposite to the second sealant layer corresponds to the first surface 8a of the lid material 8.

[0133] 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 bottom material 9 where the recess 91 is not provided. The area of ​​the second surface 9b of the bottom material 9 where the recess 91 is provided is not sealed with the second surface 8b of the lid material 8, and in this area, the second surface 9b of the bottom material 9 and the second surface 8b of the lid material 8 form a storage section 198. The contents 7 are sealed and stored in the storage section 198 of the packaging body 101.

[0134] The opening of the recess 91 is circular or nearly circular (approximately circular). In this specification, nearly circular means a shape that is not circular but is approximately circular in shape, and cannot be clearly recognized as non-circular by visual inspection. The bottom surface of the recess 91 may be either flat or non-flat (e.g., curved). When a cross-section is formed in the recess 91 in a direction parallel to the surface of the flat portion of the bottom material 9 (the area where the recess is not provided), it is preferable that the opening of the recess 91 (cross-sectional opening) is similar in shape to the above-mentioned opening, that is, circular or nearly circular.

[0135] The inner diameter of the opening of the recess 91 is preferably 8 to 15 mm. The depth of the recess 91 is preferably 3 to 8 mm. If the bottom surface of the recess 91 is not flat, the depth at the deepest part of the recess is preferably within the above numerical range.

[0136] A slit 92 is formed on the first surface 9a side of the base material 9. More specifically, in the base material 9, multiple slits 92 are formed parallel to each other in the width direction of the packaging body 101. Each slit 92 is formed over the entire width of the packaging body 101. The presence of the slits 92 allows the packaging body 101 to be easily divided into specific numbers of storage compartments 198, thereby increasing the convenience of the packaging body 101.

[0137] The contents 7 are preferably tablets. Examples of suitable tablets include those having physical properties similar to ordinary pharmaceuticals, such as hardness.

[0138] In the packaging 101, the sealing strength of the bottom material 9 and the lid material 8 is high. In the packaging 101, by adjusting the content of ethylene-vinyl acetate copolymer in the sealant layer in the resin film, the appearance of the peel surface of the bottom material 9 (the second surface 9b of the bottom material 9 after the lid material 8 is heat-sealed and then peeled off) is improved. In the packaging 101, by adjusting the content of homopolypropylene in the sealant layer in the resin film, the plug moldability of the resin film is improved, and the depth of the recess 91 of the bottom material 9 does not become shallow. When the lid material 8 contains the propylene-based resin, the packaging 101 (bottom material 9 and lid material 8) is monomaterialized, which improves the reusability of the packaging 101.

[0139] The packaging of this embodiment is not limited to the above-described configuration, and some configurations may be modified, deleted, or added without departing from the spirit of the present invention. For example, in the packaging 101, two rows of storage compartments 198 are provided in the width direction and four rows of storage compartments 198 are provided in the length direction, but the number of storage compartments provided in the width direction and length direction of the packaging of this embodiment is not limited to these. For example, in the packaging 101, a slit 92 is provided in the bottom material 9, but the bottom material in the packaging of this embodiment does not need to have a slit. For example, in the packaging 101, the opening of the recess 91 in the bottom material 9 is circular or substantially circular (approximately circular), but in the packaging of this embodiment, the opening of the recess in the bottom material may be of any other shape. Similarly, when a cross-section is formed in the recess in a direction parallel to the surface (first surface) of the flat portion (area without a recess) of the bottom material, the opening of the recess may be circular or substantially circular, or of any other shape. The shape of the recess can be arbitrarily set according to the shape of the stored items.

[0140] <Example of a Packaging> A preferred example of a packaging according to this embodiment is a blister pack packaging composed of a lid material and a bottom material seal, wherein the bottom material is a molded resin film, the lid material contains a propylene resin, the resin film comprises a base layer and a sealant layer provided on one surface of the base layer, the base layer contains a propylene resin, the sealant layer contains homopolypropylene and an α-olefin elastomer, the content of homopolypropylene in the sealant layer is 50% by mass or more of the total mass of the sealant layer, the content of α-olefin elastomer in the sealant layer is 20% by mass or more of the total mass of the sealant layer, the sealant layer may or may not contain an ethylene-vinyl acetate copolymer, and if the sealant layer contains the ethylene-vinyl acetate copolymer, the content of the ethylene-vinyl acetate copolymer in the sealant layer is 10% by mass or more of the total mass of the sealant layer. An example of a packaging body is one in which the base layer contains homopolypropylene or a homopolypropylene and propylene copolymer as the propylene resin, the ratio of the homopolypropylene content to the total mass of the base layer is 70 to 100% by mass, and the ratio of the propylene copolymer content to the total mass of the base layer is 0 to 30% by mass.

[0141] In the sealant layer of the resin film in such packaging, it is preferable that the total content ratio of homopolypropylene, the α-olefin elastomer, and the ethylene-vinyl acetate copolymer to the total mass of the sealant layer is 80% by mass or more. In the sealant layer of the resin film in such packaging, it is preferable that the content ratio of the ethylene-vinyl acetate copolymer to the total mass of the sealant layer is 40% by mass or less. In the base layer of the resin film in such packaging, it is preferable that the content ratio of the propylene resin to the total mass of the base layer is 80% by mass or more. The resin film in such packaging may further include an outer layer provided on the side of the base layer opposite to the side of the sealant layer (the other side or second side), the composition of the outer layer may be the same as the composition of the sealant layer, and the composition and thickness of the outer layer may be the same as the composition and thickness of the sealant layer. The lid material in such a package comprises a second base material layer and a second sealant layer provided on one surface of the second base material layer, wherein the second sealant layer and the second base material layer preferably contain a propylene resin, wherein in the second sealant layer, the ratio of the propylene resin content to the total mass of the second sealant layer is preferably 80% by mass or more, and in the second base material layer, the ratio of the propylene resin content to the total mass of the second base material layer is preferably 80% by mass or more. In such a package, when the heat sealing temperature of the bottom material and lid material is 125°C, the seal strength of the bottom material and lid material is preferably 6.5 N / 15 mm or more. In such a package, when the heat sealing temperature of the bottom material and lid material is 135°C, the seal strength of the bottom material and lid material is preferably 8.5 N / 15 mm or more.

[0142] <<Manufacturing Method for Packaging>> The packaging can be manufactured in the same way as known packaging, except that it uses a resin film according to the above-described embodiment of the present invention. For example, the packaging can be manufactured by heat-sealing the resin film or a molded body thereof (e.g., a base material) and the object to be sealed (e.g., a lid material) while forming a storage compartment and storing the object to be packaged within the storage compartment.

[0143] The molded resin film, such as the bottom material, can be manufactured by known methods. For example, the bottom material for blister pack packaging can be manufactured by forming the recess in the resin film using a known PTP packaging machine by plug molding, air-assisted plug molding, pressure molding, plug-assisted pressure molding, vacuum molding, etc.

[0144] The molding temperature of the resin film is preferably 125 to 145°C. When molding the resin film using a plug, the temperature of the heating plate is preferably within the above numerical range, and the plug temperature is preferably 15 to 25°C.

[0145] During heat sealing of the resin film or molded body thereof with the object to be sealed, the sealing temperature is preferably 120 to 160°C, the sealing speed is preferably 3 to 12 m / min, and the sealing pressure is preferably 0.2 to 0.5 MPa.

[0146] When providing a slit in the base material (for example, a slit 92 in the case of base material 9 shown in Figures 2 and 3), the slit can be formed in the base material by a known method using a sewing blade or a half-cut blade.

[0147] The lid material can be manufactured by known methods. For example, a lid material comprising the second base material layer and the second sealant layer described above can be manufactured using a resin or resin composition, etc., which will be the forming material, in the same manner as in the case of the resin film described above.

[0148] Examples of resin compositions for forming a second sealant layer include resin composition (F) comprising an α-olefin elastomer, an ethylene-vinyl acetate copolymer, homopolypropylene if necessary, and the other components as necessary. Examples of resin compositions for forming a second substrate layer include resin composition (G) comprising a propylene resin and the other components as necessary.

[0149] The resin composition for forming each layer in the lid material can be manufactured and used in the same manner as the resin composition for forming each layer in the resin film.

[0150] The present invention will be described in more detail below with reference to specific examples. However, the present invention is not limited in any way to the examples shown below.

[0151] The resins used in each example or comparative example are as follows: hPP: Homopolypropylene (Prime Polymer Co., Ltd. "E122V", melting point 157°C, melt flow rate 2.6 g / 10 min) rPP(1): Polypropylene random copolymer (propylene-ethylene binary copolymer, Prime Polymer Co., Ltd. "J242WB", melting point 140°C, melt flow rate (230°C) 1.3 g / 10 min) rPP(2): Polypropylene random copolymer (propylene-ethylene random copolymer, Sumitomo Chemical Co., Ltd. "Noblen® S131", melting point 132°C, melt flow rate 1.5 g / 10 min) TPO: α-olefin elastomer (propylene elastomer, Mitsui Chemicals, Ltd. "Tafmer XM7080", melt flow rate 3 g / 10 min, melting point 83°C) EVA: Ethylene-vinyl acetate copolymer (Evaflex V5714C, manufactured by Mitsui Dow Polychemicals, melt flow rate (190°C) 2.7 g / 10 min, melting point 89°C, vinyl acetate content 16% by mass)

[0152] [Example 1] <<Production of resin film>> <Production of resin composition> At room temperature, the resin composition (S1) was produced by mixing the hPP (80 parts by mass) and the TPO (20 parts by mass).

[0153] <Manufacturing of Resin Film> By co-extruding the resin composition (S1), the hPP, and the resin composition (S1) in this order, a long resin film (resin film for base material) (thickness 300 μm) with the configuration shown in Figure 1 was manufactured, in which a sealant layer (thickness 15 μm), a base layer (thickness 270 μm), and an outer layer (thickness 15 μm) were laminated in this order in the thickness direction.

[0154] <<Manufacturing of Blister Packaging>> <Manufacturing of Bottom Material> Using a packaging machine (CKD Corporation "FBP-300E"), the bottom material was manufactured by plug molding on the long resin film obtained above, under the following molding conditions, by forming numerous recesses with openings on the exposed surface of the sealant layer. [Molding Conditions] Molding mold: Lens-shaped, Size (opening diameter): 10 mm diameter, Depth: 5 mm Heating plate temperature: 134°C Plug temperature: 20°C

[0155] <Manufacturing of Lid Material> At room temperature, a resin composition (F1) was manufactured by mixing the TPO (80 parts by mass) and the EVA (20 parts by mass). A long lid material (resin film for lid material) (40 μm thick) was manufactured by co-extruding the resin composition (F1) and the hPP in this order, thereby laminating a second sealant layer (4 μm thick) and a second base material layer (36 μm thick) in this order in the thickness direction.

[0156] <Manufacturing of blister pack packaging (125°C sealed product)> The bottom material and lid material obtained above are sealed at a sealing temperature of 125°C, a sealing speed of 11 m / min, and a sealing pressure of 0.45 MPa (4.6 kgf / cm²). ２ The product was heat-sealed under the following conditions. At this time, the side of the bottom material on which the recess is open (i.e., the exposed surface of the sealant layer) was sealed with the exposed surface of the second sealant layer of the lid material. As a result, a blister pack packaging was manufactured in which the numerous recesses of the bottom material were sealed by the lid material.

[0157] <Manufacturing of blister pack packaging (135°C sealed product)> Except for changing the sealing temperature between the bottom material and the lid material from 125°C to 135°C, the blister pack packaging was manufactured in the same manner as described above.

[0158] <<Evaluation of Resin Film>> <Measurement of 125°C Seal Strength (125°C Peel Strength) of Bottom and Lid Materials> A 5 ​​mm wide test piece was cut from the area of ​​the bottom material where no recess was formed (flat area) of the blister pack packaging (125°C sealed product) obtained above. At one end of this test piece in the longitudinal direction, the lid material was slightly peeled from the bottom material. Using a tensile testing machine (TENSILON RTG-1310, manufactured by A&D Co., Ltd.), the lid material was peeled from the bottom material at a peeling speed of 100 mm / min and a peeling angle (angle between the peeling surface of the bottom material and the peeling surface of the lid material) of 180°, starting from the peeled area of ​​the lid material at the end of the test piece, in the longitudinal direction of the test piece (i.e., from one end to the other). The peeling distance was set to 5 mm, and the value in which the variation of the measured peel strength during this period was suppressed was adopted as the peel strength. These measured values ​​were then converted to values ​​corresponding to a test specimen width of 15 mm and adopted as the sealing strength (N / 15 mm) of the base and lid materials. The results are shown in Table 1.

[0159] <Measurement of 135°C seal strength (135°C peel strength) of bottom and lid materials> For the blister pack packaging (135°C sealed) obtained above, the seal strength (N / 15mm) of the bottom and lid materials was measured in the same manner as for the 125°C sealed product. The results are shown in Table 1.

[0160] <Evaluation of the appearance of the peeled surface of the bottom material> For the blister pack packaging (135°C sealed) obtained above, the lid material was peeled off from the bottom material, and the appearance of the peeled surface of the bottom material was visually observed. The appearance was then evaluated according to the following criteria. The results are shown in Table 1. [Evaluation Criteria] A: The seal mark is clearly visible over the entire peeled surface of the bottom material, and the appearance is excellent. B: The seal mark is somewhat faint but visible over the entire peeled surface of the bottom material, and the appearance is good. C: A faint seal mark is only visible in a limited area of ​​the peeled surface of the bottom material, and the appearance is somewhat poor. D: The seal mark is not clearly visible over the entire peeled surface of the bottom material, and the appearance is clearly poor.

[0161] <Evaluation of plug moldability of resin film> In the bottom material of the blister pack packaging obtained above, multiple recesses in a specific area were randomly observed visually to check for any abnormalities in recess formation, specifically whether the depth of the recesses was shallower than usual. The plug moldability of the resin film was then evaluated according to the following criteria. The results are shown in Table 1. [Evaluation Criteria] A: No abnormalities were observed in any of the recesses, indicating excellent plug moldability of the resin film. B: Abnormalities in recess formation were rarely observed, indicating good plug moldability of the resin film. C: Abnormalities in recess formation occurred frequently, indicating poor plug moldability of the resin film.

[0162] <<Manufacturing of resin film and blister pack packaging, and evaluation of resin film>> [Example 2] At room temperature, a resin composition (S2) was manufactured by mixing the above hPP (50 parts by mass), the above TPO (30 parts by mass), and the above EVA (20 parts by mass). Then, a resin film and a blister pack packaging were manufactured in the same manner as in Example 1, except that resin composition (S2) was used instead of resin composition (S1), and the resin film was evaluated. The results are shown in Table 1.

[0163] [Example 3] At room temperature, a resin composition (S3) was prepared by mixing the hPP (60 parts by mass), the TPO (20 parts by mass), and the EVA (20 parts by mass). Then, a resin film and a blister pack packaging were prepared in the same manner as in Example 1, except that resin composition (S3) was used instead of resin composition (S1), and the resin film was evaluated. The results are shown in Table 1.

[0164] [Example 4] A resin composition (B1) was prepared by mixing the hPP (70 parts by mass) and the rPP (1) (30 parts by mass) at room temperature. Then, a resin film and a blister pack were prepared in the same manner as in Example 3, except that the resin composition (B1) was used instead of the hPP when preparing the resin film for the base material, and the resin film was evaluated. The results are shown in Table 1.

[0165] [Example 5] At room temperature, a resin composition (S4) was prepared by mixing the hPP (65 parts by mass), the TPO (20 parts by mass), and the EVA (15 parts by mass). Then, a resin film and a blister pack packaging were prepared in the same manner as in Example 1, except that resin composition (S4) was used instead of resin composition (S1), and the resin film was evaluated. The results are shown in Table 1.

[0166] [Example 6] At room temperature, a resin composition (S5) was prepared by mixing the hPP (70 parts by mass), the TPO (20 parts by mass), and the EVA (10 parts by mass). Then, a resin film and a blister pack packaging were prepared in the same manner as in Example 1, except that resin composition (S5) was used instead of resin composition (S1), and the resin film was evaluated. The results are shown in Table 2.

[0167] [Comparative Example 1] A long resin film (resin film for bottom material) (300 μm thick) was manufactured by co-extruding the rPP(2), the hPP, and the rPP(2) in this order, thereby laminating a sealant layer (15 μm thick), a base layer (270 μm thick), and an outer layer (15 μm thick) in this order in the thickness direction. Except for using the resin film obtained here as the resin film for bottom material, a blister pack was manufactured and the resin film was evaluated in the same manner as in Example 1. The results are shown in Table 2.

[0168] [Comparative Example 2] A long resin film (resin film for bottom material) (300 μm thick) was manufactured by co-extruding the rPP(1), the hPP, and the rPP(1) in this order, thereby laminating a sealant layer (15 μm thick), a base layer (270 μm thick), and an outer layer (15 μm thick) in this order in the thickness direction. Except for using the resin film obtained here as the bottom material, a blister pack was manufactured and the resin film was evaluated in the same manner as in Example 1. The results are shown in Table 2.

[0169] [Comparative Example 3] A resin composition (RS1) was prepared by mixing the hPP (93 parts by mass) and the TPO (7 parts by mass) at room temperature. Then, a resin film and a blister pack packaging were prepared in the same manner as in Example 1, except that resin composition (RS1) was used instead of resin composition (S1), and the resin film was evaluated. The results are shown in Table 2.

[0170] The resin films for the base material produced in Examples 1-6 and Comparative Examples 1-3 are all unstretched resin films.

[0171] In Tables 1 and 2, the "-" in the "Components and Content (parts by mass)" column under "Composition of Resin Film" means that the corresponding layer in the resin film for the base material does not contain that component.

[0172]

[0173]

[0174] As is clear from the above results, in Examples 1 to 6, the 125°C seal strength of the bottom material and lid material was 6.8 N / 15 mm or more (6.8 to 12 N / 15 mm), and the 135°C seal strength was 8.5 N / 15 mm or more (8.5 to 14.6 N / 15 mm), both of which were sufficiently high. In Examples 1 to 6, the base layer in the resin film contained a propylene-based resin, and the sealant layer in the resin film contained homopolypropylene (hPP) and α-olefin-based elastomer (TPO). In the sealant layer, the ratio of homopolypropylene content to the total mass of the sealant layer was 50% by mass or more (50 to 80% by mass), and the ratio of α-olefin-based elastomer content to the total mass of the sealant layer was 20% by mass or more (20 to 30% by mass).

[0175] In the resin films of Examples 1 to 6, the content of homopolypropylene relative to the total mass of the base layer was 70% by mass or more (70 to 100% by mass), and the content of propylene copolymer relative to the total mass of the base layer was 30% by mass or less (0 to 30% by mass).

[0176] From a comparison of Examples 1 to 6 and Comparative Example 3, it was observed that the higher the proportion of homopolypropylene in the sealant layer, the more likely the plug moldability of the resin film was to improve.

[0177] A comparison of Examples 2, 3, and 5 revealed that, in the sealant layer, the lower the proportion of homopolypropylene (in other words, the higher the proportion of α-olefin elastomer), the greater the seal strength of the bottom material and lid material (especially the 125°C seal strength).

[0178] In the sealant layers of Examples 1 to 6, the ratio of ethylene-vinyl acetate copolymer content to the total mass of the sealant layer was 0 to 20% by mass. A comparison of these examples confirmed that the higher the ratio, the better the appearance of the peeled surface of the base material.

[0179] A comparison of Examples 3, 5, and 6 revealed that, in the sealant layer, the lower the proportion of homopolypropylene and the higher the proportion of ethylene-vinyl acetate copolymer, the greater the tendency for the seal strength of the bottom material and lid material (especially the 125°C seal strength) to increase.

[0180] A comparison of Examples 3 and 4 revealed that the inclusion of a propylene copolymer in the base layer tended to improve the plug moldability of the resin film, while the sealing strength of the bottom and lid materials tended to decrease.

[0181] In contrast, in Comparative Examples 1 to 3, the 125°C seal strength of the bottom material and lid material was low, at 5.5 N / 15 mm or less (2.5 to 5.5 N / 15 mm). Furthermore, in Comparative Example 3, the 135°C seal strength of the bottom material and lid material was also low, at 4.3 N / 15 mm. In Comparative Examples 1 and 2, the sealant layer in the resin film did not contain homopolypropylene and α-olefin elastomer, but contained only polypropylene random copolymer. In Comparative Example 3, the sealant layer in the resin film contained homopolypropylene and α-olefin elastomer, but the ratio of α-olefin elastomer content to the total mass of the sealant layer was low, at 7% by mass.

[0182] The present invention can be used in the manufacture of blister pack packaging, and is particularly suitable for use in the manufacture of blister pack packaging with high reusability due to monomaterialization.

[0183] 1... Resin film 11... Base layer, 11a... One side of the base layer (first side) 12... Sealant layer 101... Packaging (blister pack packaging) 8... Lid material 9... Bottom material

Claims

1. A resin film for use as a bottom material for a blister pack packaging, wherein the resin film comprises a base layer and a sealant layer provided on one surface of the base layer, the base layer contains a propylene resin, the sealant layer contains homopolypropylene and an α-olefin elastomer, the content of homopolypropylene in the sealant layer is 50% by mass or more of the total mass of the sealant layer, and the content of α-olefin elastomer in the sealant layer is 20% by mass or more of the total mass of the sealant layer.

2. The resin film according to claim 1, wherein the sealant layer further comprises an ethylene-vinyl acetate copolymer, and in the sealant layer, the ratio of the content of the ethylene-vinyl acetate copolymer to the total mass of the sealant layer is 10% by mass or more.

3. The resin film according to claim 1 or 2, wherein the base layer comprises homopolypropylene or a homopolypropylene and propylene copolymer as the propylene resin, the ratio of the homopolypropylene content to the total mass of the base layer is 70 to 100% by mass, and the ratio of the propylene copolymer content to the total mass of the base layer is 0 to 30% by mass.

4. A packaging body made using the resin film described in claim 1 or 2.

5. The packaging according to claim 4, wherein the packaging is a blister pack packaging composed of a lid material and a bottom material seal, the bottom material is a molded body of the resin film, and the lid material contains a propylene resin.

6. A packaging body constructed using the resin film described in claim 3.

7. The packaging according to claim 6, wherein the packaging is a blister pack packaging composed of a lid material and a bottom material seal, the bottom material is a molded body of the resin film, and the lid material contains a propylene resin.

Images