JP2024067220A - Press-through lid - Google Patents

Abstract

[Problem] The present invention provides a novel press-through lid material that is easy to process and has good press-through properties. [Solution] The press-through lid material 10 of the present invention does not have a metal foil layer, but has a base resin layer 12, the base resin layer contains a first thermoplastic resin and a second thermoplastic resin, the first thermoplastic resin has an elongation at break in either the MD direction or the TD direction of 80% or more, the second thermoplastic resin has an elongation at break in either the MD direction or the TD direction of 50% or less, the first thermoplastic resin and the second thermoplastic resin are compatible, and the content of the second thermoplastic resin is 15 to 80% by mass relative to the mass of the base resin layer. [Selected Figure] Figure 1

Description

The present invention relates to a press-through lid material.

Conventionally, blister packs have been used as packaging containers for solid preparations such as tablets or capsules containing medicine. These blister packs can be formed by forming a blister container by forming a recess called a pocket in a blister container sheet made of a resin sheet or the like, placing the contents in the pocket, and then joining the lid material by heat sealing or the like.

When a blister container contains a formulation or the like inside the pocket, a lid is heat-sealed around the flared hem to form a blister pack containing the formulation or the like. One form of such a blister pack is known as a PTP (press-through package), in which the pocket is crushed with a finger or the like to break the lid and release the contents.

Metal foil such as aluminum foil is widely used as the lid material for PTPs from the viewpoint of ease of opening, but because the lid material is metal foil (inorganic) and the blister container is made of resin (organic), which are completely different materials, they require separate processing, and recycling or incineration after use has been very difficult. As a result, various resin lid materials have been proposed that are suitable for use in PTPs, i.e., have improved opening properties when broken open.

Patent Document 1 discloses a lid material for press-through pack packaging having a heat seal layer made of a heat seal agent and a lid material film. Patent Document 1 also discloses that the lid material contains a styrene-based resin.

Patent Document 2 discloses a lid material film for press-through packs, which is characterized by being made of a stretched film having at least one layer containing a thermoplastic resin and less than 5 parts by mass of an inorganic filler per 100 parts by mass of the thermoplastic resin.

Patent Document 3 discloses a PTP lid material sheet, which is characterized in that a sheet having a thickness of 0.01 to 1 mm is made of a resin composition containing 5 to 250 parts by weight of an inorganic filler for 100 parts by weight of a resin (A) consisting of at least one of polyolefin, polyester, polyvinyl chloride, polystyrene, and a styrene copolymer, and has a burst strength of 0.01 to 5 kg/ ^cm2 according to a method based on the Mullen low pressure test of JIS P8112.

Patent Document 4 discloses a top film for PTP packaging, which is formed by laminating a sealant layer of 10 to 40 μm in thickness to a polyethylene terephthalate film or polypropylene film of 10 to 30 μm in thickness having a large number of fine holes formed all over the surface, and which is characterized in that the holes are formed in an inverted cone or pyramid shape, or an inverted truncated cone or truncated pyramid shape facing the sealant layer, have a diameter of 15 μmφ or less at the laminated surface with the sealant layer, and have 400 to 3000 such holes per ^cm2 .

Patent document 5 discloses a package formed by welding a film or sheet having a recess (pocket) formed in a portion thereof to a lid material, the combined thickness of the film or sheet and the lid material being 250 μm or less, the total thickness of the metal foil contained in the film or sheet and the lid material being 35 μm or less, or no metal foil being used, the package being characterized in that the part of the package where the lid material is welded to the film or sheet is cut at a right angle to create a cut piece, and when a prescribed piercing test is carried out, the cut piece does not penetrate the 25 μm thick aluminum foil.

JP 2018-188181 A JP 2010-264987 A Japanese Patent Application Laid-Open No. 10-101133 Utility Model Registration No. 3035462 JP 2018-2304 A

When a styrene-based resin is used, as in the invention of Patent Document 1, the press-through property is improved to some extent, but the processability is sometimes not good due to the insufficient solvent resistance and heat resistance of polystyrene.

When fillers are used, as in Patent Documents 2 and 3, organic and inorganic materials are mixed together, which can have a negative impact on recycling and disposal.

In addition, when attempting to improve the ease of opening by mechanical processing, as in Patent Documents 4 and 5, precise control of the processing position, etc. is required, and in particular when through holes are provided in the lid material, the sealing ability of the resulting lid material may be impaired.

Therefore, the present invention provides a new press-through lid material that is easy to process and has good press-through properties.

As a result of intensive research, the present inventors have found that the above problems can be solved by the following means, and have completed the present invention. That is, the present invention is as follows:
<Embodiment 1> No metal foil layer and a base resin layer,
the base resin layer contains a first thermoplastic resin and a second thermoplastic resin,
The first thermoplastic resin has an elongation at break in either the MD direction or the TD direction of 80% or more;
The second thermoplastic resin has an elongation at break in both the MD direction and the TD direction of 50% or less,
The first thermoplastic resin and the second thermoplastic resin are compatible with each other,
The content of the second thermoplastic resin is 15 to 80% by mass relative to the mass of the base resin layer.
Press-through lid material.
<Aspect 2> The first thermoplastic resin has an elongation at break in either the MD direction or the TD direction of 100% or more,
The second thermoplastic resin has an elongation at break in both the MD direction and the TD direction of 40% or less.
The press-through lid material according to embodiment 1.
<Aspect 3> The press-through lid material according to aspect 1 or 2, wherein the first thermoplastic resin is a first polypropylene-based resin.
<Aspect 4> The second thermoplastic resin is at least one selected from the group consisting of a cyclic olefin copolymer, a polyethylene-based resin, and a second polypropylene-based resin. The press-through lid material according to any one of aspects 1 to 3.
<Embodiment 5> The press-through lid material according to any one of embodiments 1 to 4, further comprising a heat seal layer, the heat seal layer having a thickness of 10 μm or less.
<Embodiment 6> The press-through lid material according to any one of embodiments 1 to 5, further comprising a printed layer.
<Aspect 7> The press-through lid material according to any one of aspects 1 to 6, having the following characteristics:
Maximum tensile load: 8 to 65 N/15 mm
Tensile elongation at break: 72%/15 mm or less <Aspect 8> Contents,
A blister pack containing a content, the blister pack having a pocket portion and containing the content in the pocket portion; and the press-through lid material according to any one of aspects 1 to 7, which is adhered to the blister container to seal the content.

The present invention provides a new press-through lid material that is easy to process and has good press-through properties.

FIG. 1 is a side cross-sectional view of a press-through lid material of the present invention. FIG. 2 is a side cross-sectional view of a filled blister pack of the present invention.

<Press-through lid material>
As shown in FIG. 1(a), the press-through lid material 10 of the present invention has the following features:
The film does not have a metal foil layer and has a base resin layer 12;
the base resin layer contains a first thermoplastic resin and a second thermoplastic resin,
The first thermoplastic resin has an elongation at break in either the MD direction or the TD direction of 80% or more;
The second thermoplastic resin has an elongation at break in both the MD direction and the TD direction of 50% or less,
The first thermoplastic resin and the second thermoplastic resin are compatible with each other,
The content of the second thermoplastic resin is 15 to 80% by mass relative to the mass of the base resin layer.

The first thermoplastic resin, which has a large elongation at break, has stable processability, but when this resin is used as a lid material, the lid material is stretched when the contents are pushed out, which can have a negative effect on press-through.

On the other hand, when a second thermoplastic resin with a low breaking elongation was used as the lid material, the press-through properties were good, but meandering and bending could occur during processing.

In response to this, the inventors have discovered that by incorporating the first and second thermoplastic resins in the above ratio, a press-through lid material that is easy to process and has good press-through properties can be obtained.

The press-through lid of the present invention does not include a metal foil layer. Examples of the metal foil layer include an aluminum foil layer.

In the present invention, the elongation at break is measured in accordance with JIS K 7161-1:2014. More specifically, the resin or resin composition to be measured is molded to a thickness of 60 μm, cut into strips with a width of 15 mm and a length of 100 mm, and a tensile test is performed using these strips at a tensile speed of 300 mm/min and a support distance of 50 mm to obtain the elongation at break.

When the above tensile test is performed, the press-through lid material of the present invention can have various characteristic physical properties, specifically, the maximum load, the elongation at the maximum, the elongation at the breaking point, and the displacement from the maximum to the breaking point. These values can be obtained from the stress-strain curve obtained by the above tensile test.

The maximum point load of the press-through lid material of the present invention can be 8 N/15 mm or more, 10 N/15 mm or more, or 12 N/15 mm or more in both the MD and TD directions, and can be 65 N/15 mm or less, 62 N/15 mm or less, 60 N/15 mm or less, 55 N/15 mm or less, 50 N/15 mm or less, 45 N/15 mm or less, or 42 N/15 mm or less. This maximum point load is the maximum value of stress in the stress-strain curve.

The maximum elongation of the press-through lid material of the present invention can be 25% or less, 20% or less, 15% or less, 10% or less, 8% or less, or 6% or less in both the MD and TD directions, and can be 1% or more, or 2% or more. This maximum elongation refers to the elongation of the sample when the stress is maximum in the stress-strain curve.

The elongation at break of the press-through lid material of the present invention can be 75% or less, 70% or less, 65% or less, 60% or less, 55% or less, 50% or less, 45% or less, 40% or less, 35% or less, 30% or less, 28% or less, 25% or less, or 23% or less in both the MD and TD directions, and can be 1% or more, or 2% or more. In particular, when the elongation at break is 20% or less, the press-through lid material of the present invention has good press-through properties. The elongation at break means the elongation of the sample when breakage of the sample can be confirmed.

The displacement from the maximum point to the breaking point of the press-through lid material of the present invention can be 70% or less, 65% or less, 60% or less, 55% or less, 50% or less, 45% or less, 40% or less, 35% or less, 30% or less, 25% or less, 23% or less, 20% or less, or 19% or less, and can be 5% or more, 7% or more, or 10% or more. This displacement is the difference between the maximum point elongation and the breaking point elongation.

In particular, good press-through properties can be obtained when the maximum load is 65 N/15 mm or less and the elongation at break is 20% or less.

In another embodiment, as shown in FIG. 1(b), the press-through lid material 10 of the present invention may have an optional sealant layer 14, a printing layer 16, and a coating layer 18. The printing layer 16 may be present between the base resin layer 12 and the sealant layer 14, or between the base resin layer 12 and the coating layer 18. The coating layer 18 may be present on the side of the base resin layer 12 opposite the sealant layer 14.

The components of the present invention are described below.

<Base resin layer>
The base resin layer is a resin layer containing a first thermoplastic resin and a second thermoplastic resin.

The first thermoplastic resin and the second thermoplastic resin are compatible. In the present invention, "compatible" means that these thermoplastic resins are mixed together without separating from each other. This compatibility is achieved, for example, by the first and second thermoplastic resins being composed of crystalline resins.

Examples of crystalline resins include polyethylene-based resins, polypropylene-based resins, cyclic olefin copolymers, polyamides, polyacetal-based resins, and polyester-based resins.

In this specification, a polyethylene resin is a resin that contains more than 50 mol%, 60 mol% or more, 70 mol% or more, or 80 mol% or more of ethylene group repeat units in the polymer main chain, and is selected from the group consisting of, for example, low density polyethylene (LDPE), linear low density polyethylene (LLDPE), medium density polyethylene (MDPE), high density polyethylene (HDPE), ethylene-acrylic acid copolymer (EAA), ethylene-methacrylic acid copolymer (EMAA), ethylene-ethyl acrylate copolymer (EEA), ethylene-methyl acrylate copolymer (EMA), and derivatives thereof, and mixtures thereof.

A polypropylene-based resin is a resin that contains more than 50 mol%, 60 mol% or more, 70 mol% or more, or 80 mol% or more of repeating units of propylene groups in the main chain of the polymer. Examples of polypropylene-based resins that can be used include polypropylene (PP) homopolymer, random polypropylene (random PP), block polypropylene (block PP), chlorinated polypropylene, acid-modified polypropylene, and derivatives thereof, as well as mixtures thereof.

Cyclic olefin copolymer (COC) is a copolymer that can be obtained by mixing α-olefins and cyclic olefins in a hydrocarbon solvent such as hexane, heptane, octane, cyclohexane, benzene, toluene, or xylene with a catalyst such as a Ziegler catalyst or a metallocene catalyst.

The thickness of the substrate resin layer may be 20 μm or more, 25 μm or more, 30 μm or more, 35 μm or more, 40 μm or more, 45 μm or more, 50 μm or more, or 55 μm or more, and may be 120 μm or less, 110 μm or less, 100 μm or less, 95 μm or less, 90 μm or less, or 85 μm or less.

The base resin layer can be produced by kneading the resin composition that constitutes the base resin layer using, for example, a batch kneader such as a kneader, Banbury mixer, or mixing roll conical mixer, or a continuous kneader such as a twin-screw kneader, and then molding the kneaded resin into a film by an extrusion molding method such as an inflation method or a T-die method.

(First Thermoplastic Resin)
The first thermoplastic resin is a thermoplastic resin having an elongation at break in either the MD direction or the TD direction of 80% or more.

Here, the elongation at break of the first thermoplastic resin in either the MD direction or the TD direction may be 80% or more, 85% or more, 90% or more, 95% or more, 100% or more, 105% or more, 110% or more, 115% or more, 120% or more, 125% or more, or 130% or more, and may be 200% or less, 190% or less, 180% or less, 170% or less, 160% or less, or 150% or less.

The higher the tensile strength of the thermoplastic resin, for example, the nominal tensile strain at break, the higher the elongation at break. In particular, the nominal tensile strain at break of the first thermoplastic resin may be 120% or more, 150% or more, 170% or more, or 190% or more, and may be 600% or less, 550% or less, 530% or less, 500% or less, 470% or less, 450% or less, 430% or less, 400% or less, 370% or less, 350% or less, 320% or less, 300% or less, 280% or less, 250% or less, or 220% or less. Thermoplastic resins commercially available as those having the above nominal tensile strain at break can be used as the first thermoplastic resin in the present invention.

As the first thermoplastic resin, for example, a polypropylene-based resin that satisfies the above conditions can be used. The polypropylene-based resin as the first thermoplastic resin is referred to as the "first polypropylene-based resin."

(Second Thermoplastic Resin)
The second thermoplastic resin is a thermoplastic resin having an elongation at break in both the MD direction and the TD direction of 50% or less.

The second thermoplastic resin may have an elongation at break in both the MD and TD directions of 50% or less, 45% or less, 40% or less, 35% or less, 30% or less, 25% or less, 20% or less, 15% or less, or 10% or less.

The lower the tensile strength of the thermoplastic resin, for example, the nominal tensile strain at break, the lower the elongation at break. In particular, the nominal tensile strain at break of the second thermoplastic resin may be 70% or less, 60% or less, 50% or less, 40% or less, or 30% or less, and may be 5% or more, 10% or more, or 15% or more. A commercially available thermoplastic resin having the above nominal tensile strain at break can be used as the second thermoplastic resin in the present invention. As such a second thermoplastic resin, a polyethylene-based resin, a polypropylene-based resin, or a resin composition obtained by melting a resin film commercially available as an easy-peel film containing at least one of these resins can be used. The polypropylene-based resin as the second thermoplastic resin is referred to as the "second polypropylene-based resin".

As the second thermoplastic resin that satisfies the above-mentioned elongation at break, a thermoplastic resin that is too hard to form a stable film by itself can be used. As such a thermoplastic resin, a cyclic olefin copolymer, etc. can be used.

<Sealant layer>
The sealant layer is an optional layer for heat sealing the press-through lid material to the blister container, and can be positioned closest to the contents when a filled blister pack is obtained.

The material constituting the sealant layer can be selected according to the material of the blister container used, and examples that can be used include polypropylene-based resins, polyethylene-based resins, ethylene vinyl alcohol, and acid-modified polyolefins.

The sealant layer may be in the form of a film or a coating.

The thickness of the sealant layer is preferably 10.0 μm or less, 8.0 μm or less, 5.0 μm or less, or 3.0 μm or less from the viewpoint of not impairing the press-through property. This thickness may be 0.1 μm or more, 0.3 μm or more, 0.5 μm or more, 0.7 μm or more, or 1.0 μm or more.

When the sealant layer is in the form of a film, it may be laminated to the base resin layer by heat sealing or via an adhesive layer, or it may be molded and laminated together with the base resin layer by a co-extrusion method such as a multi-layer inflation method or a multi-layer T-die method.

<Printed layer>
The printed layer may be an arbitrary printed layer for the purpose of display, decoration, etc. The printed layer may be laminated by an arbitrary printing means.

From the viewpoint of abrasion resistance, it is preferable that the printed layer is not exposed on the surface of the press-through lid material. The printed layer may be present, for example, in all or part of the area between the base resin layer and the sealant layer, or between the base resin layer and the coating layer.

<Coat layer>
The coating layer is an optional layer that can provide various functions. The coating layer may be present at any position on the press-through lid material, for example, on the opposite side of the base resin layer to the sealant layer.

The coating layer may be, for example, a protective coating layer that protects the printing layer, a heat-resistant coating layer that improves heat resistance, a barrier coating layer that improves barrier properties, etc. The material constituting the coating layer can be appropriately selected depending on the purpose of the coating layer, and for example, OP varnish, etc. can be used.

The thickness of the coating layer is preferably 3 μm or less, 2 μm or less, or 1 μm or less, from the viewpoint of not impairing the press-through properties of the press-through lid material of the present invention.

<Blister pack with contents>
As shown in FIG. 2, the content-filled blister pack 100 of the present invention includes:
Contents 30,
A blister container 20 having a pocket portion 22 and containing the contents 30 in the pocket portion 22; and the press-through lid material 10 as described above, which is adhered to the blister container 20 to seal the contents 30.
has.

<Contents>
The contents are the contents sealed in the pockets of the blister container. Such contents are not limited as long as they can deteriorate when exposed to the outside air, and examples of such contents include medicines, food, cosmetics, sanitary products, medical devices, medical instruments, electronic parts, etc. Furthermore, medicines include pharmaceutical preparations, cleaning agents, agricultural chemicals, reagents, etc.

<Blister container>
The blister container may be a blister container having pockets.

Blister containers can be manufactured, for example, by forming pockets for placing contents in a blister container sheet. Examples of methods for forming the pockets include flat-plate air pressure molding, plug-assisted air pressure molding, and drum vacuum molding.

A single-layer blister container sheet may be composed of only a base layer. A multi-layer blister container sheet may have a barrier layer, a functional layer, etc. in addition to the base layer, and may have, for example, a base layer, a barrier layer, and a functional layer in this order. Methods for bonding adjacent layers include a dry lamination method, a sand lamination method, etc.

In particular, it is preferable that the layer of the blister container sheet on the lid side contains the first or second thermoplastic resin from the viewpoint of heat sealing with the lid, and it is particularly preferable that the blister container sheet as a whole contains a resin that accounts for 50% by mass or more of the first or second thermoplastic resin, and is particularly preferably composed of this resin, from the viewpoint of matching the material with the lid and thereby facilitating recycling. For example, if the lid contains 50% by mass or more of a polypropylene-based resin as the first thermoplastic resin, it is preferable that the entire blister container sheet contains this polypropylene-based resin, and is particularly preferably composed of this polypropylene-based resin.

The thickness of the sheet for blister containers can be, for example, 500 μm or less, 450 μm or less, 400 μm or less, 350 μm or less, 300 μm or less, 250 μm or less, or 200 μm or less, and can be 100 μm or more, 120 μm, or 150 μm or more, from the viewpoint of appropriate strength, stiffness, barrier properties, etc., as a blister container.

(Blister container base layer)
The resin used in the blister container base layer is not particularly limited as long as it provides the blister container sheet with appropriate barrier properties and moldability. Examples include polyolefin resins, polypropylene resins, saturated polyesters, polyamides (e.g., Nylon (registered trademark), Nylon 6, Nylon 6,6, Nylon MXD6), cyclic polyolefins (COP, COC), and fluorine-based resins (e.g., polychlorotrifluoroethylene, polytetrafluoroethylene), and mixtures thereof. These may be used in a single layer or in a laminate of two or more layers. Preferably, the resin is one that prevents the intrusion of moisture from the outside and has excellent moisture resistance, and particularly includes polypropylene resins and cyclic polyolefins.

The thickness of the base layer may be 10 μm or more, 20 μm or more, or 30 μm or more, and may be 300 μm or less, 200 μm or less, or 100 μm or less, from the viewpoint of maintaining the barrier properties and imparting strength to the entire blister pack.

(Barrier layer for blister containers)
Examples of materials used for the barrier layer for blister containers include barrier resin layers such as cyclic olefin polymers and ethylene-vinyl alcohol copolymers; inorganic vapor deposition films such as silica vapor deposition films, aluminum vapor deposition films, alumina vapor deposition films, and silica-alumina vapor deposition films; organic coating films such as vinylidene chloride coating films, polychlorotrifluoroethylene coating films, and polyvinylidene fluoride coating films; and combinations of these.

When an inorganic vapor deposition film or an organic coating film is used as the barrier layer, the thickness of the barrier layer may be 100 nm or more, 200 nm or more, 300 nm or more, 500 nm or more, 700 nm or more, or 1 μm or more, and may be 5 μm or less, 4 μm or less, 3 μm or less, or 2 μm or less, in order to provide the blister container sheet with suitable formability and barrier properties.

When a barrier resin layer or an organic coating film is used as the barrier layer, the thickness of the barrier layer may be 7 μm or more, 10 μm or more, or 20 μm or more, and may be 100 μm or less, 80 μm or less, 60 μm or less, 50 μm or less, or 40 μm or less, in order to provide the blister container sheet with suitable formability and barrier properties.

(Other layers)
The multi-layered blister container sheet may have other optional layers, such as a functional layer, a skin layer on the functional layer, and an adhesive layer for bonding the layers together.

The present invention will be specifically described with reference to examples and comparative examples, but the present invention is not limited to these.
<<Press-through lid manufacturing>>
Example 1
50 parts by mass of a first thermoplastic resin, polypropylene (PP1, nominal tensile strain at break 200%), and 50 parts by mass of a second thermoplastic resin, polypropylene (PP2, nominal tensile strain at break 20%), were melt-kneaded and formed into a 60 μm-thick film by the cast T-die method to obtain the press-through lid material of Example 1 consisting of a base resin layer.

Examples 2 to 17 and Comparative Examples 1 to 8
Press-through lids of Examples 2 to 17 and Comparative Examples 1 to 5 made of a base resin layer were obtained in the same manner as in Example 1, except that the resins constituting the base resin layer were changed to those shown in Tables 1 to 3. In addition, as the press-through lids of Comparative Examples 6 to 8, films made of the materials shown in Table 4 were used.

Details of the materials referred to in Tables 1 to 3 are as follows:
PE-based EP: polyethylene-based easy-peel resin composition, nominal tensile strain at break 8%
COC: Cyclic olefin copolymer OPP: Biaxially oriented polypropylene AL: Aluminum OPS: Biaxially oriented polystyrene

Note that for Comparative Example 4, which used PE-based PE, and Comparative Example 5, which used COC, stable film formation was not possible, so the following tensile properties were not evaluated. Therefore, in Table 3, these evaluations are referred to as "not measurable."

<Measurement of tensile properties>
The obtained press-through lid material was cut into a rectangular shape having a width of 15 mm and a length of 100 mm, and a tensile test was carried out using the cut pieces under the conditions of a tensile speed of 300 mm/min and a support distance of 50 mm to evaluate the tensile properties.

"evaluation"
<Press-through ability>
A tablet Φ8 mm (Ebios Tablet, Asahi Group Foods Co., Ltd.) was placed on a CPP 250 μm (Super Foil E0025, Mitsubishi Chemical Co., Ltd.) sheet and sealed with the prepared press-through lid material sample. Heat sealing or adhesive was used for sealing. The pocket on the sheet side was pressed with a finger to confirm whether the tablet could be removed. The same operation was performed five times. The evaluation criteria are as follows.
A: I was able to remove the tablets all five times.
B: The tablet was removed at least once out of five times.
C: The tablet could not be removed all five times.

<Processability>
During the preparation of the press-through lid material, the state of the film was visually checked and the processability was evaluated. The evaluation criteria were as follows:
A: There was no meandering or bending due to uneven thickness, and processing was stable.
B: There was meandering and bending due to uneven thickness, and processing was unstable.

<Fusing ability>
The evaluation criteria for fusion property are as follows.
A: The blister container was fused.
B: Not fused to the blister container.

<Recyclability>
The evaluation criteria for recyclability are as follows:
A: The material constituting the lid material and the material constituting the blister container overlapped by 50% by mass or more.
B: The material constituting the lid was a resin, but the overlap between the material constituting the lid and the material constituting the blister container was less than 50% by mass.
C: The material constituting the lid material was not resin.

The configurations and evaluation results of the examples and comparative examples are shown in Tables 1 to 4.

From Table 1, it can be seen that the press-through lid materials of Examples 1 to 3, which contain PP1, whose elongation at break in either the MD or TD direction is 80% or more, and PP2, whose elongation at break in either the MD or TD direction is 50% or less, and in which the PP2 content is 15 to 80% by mass, had good press-through properties, processability, fusion properties, and recyclability.

In addition, for PE-EP, the material broke during film formation, and so a tensile test could not be performed, and it was recognized that the elongation at break in both the MD and TD directions was naturally 50% or less. For COC, the material was too hard to form a stable film, and so a tensile test could not be performed, but it was recognized that the elongation at break in both the MD and TD directions was naturally 50% or less, even without conducting a tensile test.

In fact, the press-through lid materials of Examples 4 to 17, which contain PP with an elongation at break in either the MD or TD of 80% or more, and PE-based EP or COC whose elongation at break in either the MD or TD could not be measured, and have a PE-based EP or COC content of 15 to 80% by mass, had good press-through properties, processability, fusion properties, and recyclability. From this, it can be understood that PE-based EP and COC can be considered to be equivalent to those with an elongation at break in either the MD or TD of 50% or less.

Among them, Examples 1-2, 4-7, and 10-16, which had a maximum load of 65 N/15 mm or less and an elongation at break of 25% or less, had particularly good press-through properties.

REFERENCE SIGNS LIST 10 Press-through lid material 12 Base resin layer 14 Sealant layer 16 Printed layer 18 Coating layer 20 Blister container 22 Pocket portion 30 Contents 100 Blister pack containing contents

Claims (8)

The film does not have a metal foil layer and has a base resin layer,
the base resin layer contains a first thermoplastic resin and a second thermoplastic resin,
The first thermoplastic resin has an elongation at break in either the MD direction or the TD direction of 80% or more;
The second thermoplastic resin has an elongation at break in both the MD direction and the TD direction of 50% or less,
The first thermoplastic resin and the second thermoplastic resin are compatible with each other,
The content of the second thermoplastic resin is 15 to 80% by mass relative to the mass of the base resin layer.
Press-through lid. The first thermoplastic resin has an elongation at break in either the MD direction or the TD direction of 100% or more;
The second thermoplastic resin has an elongation at break in both the MD direction and the TD direction of 40% or less.
The press-through lid material according to claim 1. The press-through lid material according to claim 1 or 2, wherein the first thermoplastic resin is a first polypropylene-based resin. The press-through lid material according to claim 1 or 2, wherein the second thermoplastic resin is at least one selected from the group consisting of a cyclic olefin copolymer, a polyethylene-based resin, and a second polypropylene-based resin. The press-through lid material according to claim 1 or 2, further comprising a heat seal layer, the thickness of which is 10 μm or less. The press-through lid material according to claim 1 or 2, further comprising a printing layer. The press-through lid material according to claim 1 or 2, having the following characteristics:
Maximum tensile load: 8 to 65 N/15 mm
Tensile elongation at break: 72%/15mm or less Contents,
A blister pack containing a content, the blister pack having a pocket portion and containing the content in the pocket portion, and the press-through lid material according to claim 1 or 2, which is adhered to the blister container to seal the content.

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