1. An aluminum laminate, comprising:

a resin layer;

a first aluminum foil attached to one surface of the resin layer; and

a second aluminum foil attached to the other surface of the resin layer,

the resin layer includes a polyhydroxyurethane resin containing at least one hydroxyl group in a structural unit.

2. The aluminum laminate as recited in claim 1,

the polyhydroxyurethane resin comprises a reaction product of a five-membered cyclic carbonate compound and an amine compound.

3. The aluminum laminate of claim 1 or 2,

at least one of the first aluminum foil and the second aluminum foil is bonded to the resin layer so that a surface opposite to the resin layer is a dull surface.

4. The aluminum laminate of claim 1 or 2,

the foil thickness of the first aluminum foil and the second aluminum foil is more than 6 mu m,

the total foil thickness, which is the sum of the foil thickness of the first aluminum foil and the foil thickness of the second aluminum foil, is 30 μm or less.

5. A packaging material for pharmaceuticals, foods, beverages, or industrial materials, comprising the aluminum laminate according to any one of claims 1 to 4.

6. A blister package comprising:

a sheet-shaped resin container including a storage section for storing an object to be stored; and

a lid member attached to the resin container so as to cover the opening of the housing, the lid member comprising the aluminum laminate according to any one of claims 1 to 4.

Background

As a packaging material for a pharmaceutical product or the like, a blister package (hereinafter, referred to as PTP) is widely used. PTP is generally composed of a container material made of resin such as polyvinyl chloride or polypropylene and including a storage portion for storing a storage object (an example of a packaged object) such as a pharmaceutical product, and a lid material made of aluminum foil and attached to the container material so as to cover an opening of the storage portion. The object to be stored sealed in the storage section is pushed toward the cover by applying a force from the outside of the storage section, and the cover is crushed to seal the PTP, thereby taking out the object.

Aluminum foil, which is a metal, has a very low moisture permeability as compared with a general packaging material made of resin or paper, and is an excellent moisture-proof material. However, in PTP, for example, when a pinhole formed in an aluminum foil serving as a cover member is disposed at a position facing a storage unit, moisture passing through the pinhole may reach a storage object and cause a drug or the like to absorb moisture. In general, in an aluminum foil having a foil thickness of less than 15 μm, the frequency of occurrence of pinholes is significantly increased as compared with an aluminum foil having a foil thickness of 15 μm or more. In addition, the PTP lid is also required to be able to be broken with an appropriate pressing force when opening while avoiding damage during manufacturing and transportation. In view of the balance between them, aluminum foil having a foil thickness of about 17 to 20 μm has been conventionally used as a cover material for PTP. However, in the aluminum foil of this range of foil thickness, pinholes are inevitably generated at a certain frequency. Therefore, patent documents 1 and 2 below disclose a lid material including an aluminum laminate to which two aluminum foils having a smaller foil thickness are bonded. In such an aluminum laminate, it is considered that, if the pinholes of the two aluminum foils are arranged so as not to overlap, moisture hardly passes through the lid material, and therefore, moisture absorption of the stored material can be effectively suppressed.

Documents of the prior art

Patent document

Patent document 1: japanese Kokai publication Sho-60-15652

Patent document 2: japanese patent No. 2970857

Disclosure of Invention

Problems to be solved by the invention

As an adhesive that can exhibit sufficient adhesion to an aluminum foil, a two-pack curable adhesive containing an isocyanate group has been used. However, when aluminum foils are bonded to each other using such an isocyanate-based two-pack adhesive, partial bulging may occur in the aluminum laminate at the site where pinholes are formed when the adhesive is reacted and cured (Japanese text: ふくれ). For example, if a partial bulge is generated in an aluminum laminate used as a cover material of PTP, it may cause a trouble when printing is performed on the cover material. Therefore, the aluminum laminate has not been widely used as a packaging material used for printing.

The technology disclosed in the present specification has been made in view of the above circumstances, and an object thereof is to provide an aluminum laminate having good printability and excellent moisture resistance, and a packaging material and a blister package each including the aluminum laminate.

Means for solving the problems

As a result of intensive studies, the present inventors have found that an aluminum laminate having sufficient bonding strength without causing partial swelling can be obtained by bonding a first aluminum foil and a second aluminum foil via a resin layer containing a polyhydroxyurethane resin having at least one hydroxyl group in a structural unit, and have completed the present invention. That is, the present specification discloses the following techniques of <1> - < 6 >.

<1> an aluminum laminate characterized by comprising: a resin layer; a first aluminum foil attached to one surface of the resin layer; and a second aluminum foil bonded to the other surface of the resin layer, wherein the resin layer contains a polyhydroxyurethane resin having at least one hydroxyl group in a structural unit.

<2> the aluminum laminate according to <1> above, wherein the polyhydroxyurethane resin comprises a reaction product of a five-membered cyclic carbonate compound and an amine compound.

<3> the aluminum laminate according to <1> or <2>, wherein at least one of the first aluminum foil and the second aluminum foil is bonded to the resin layer so that a surface opposite to the resin layer is a dull surface.

<4> the aluminum laminate according to any one of <1> to <3>, wherein the first aluminum foil and the second aluminum foil each have a foil thickness of 6 μm or more, and wherein the total foil thickness, which is the sum of the foil thicknesses of the first aluminum foil and the second aluminum foil, is 30 μm or less.

<5> a packaging material for pharmaceuticals, foods, beverages, or industrial materials, which comprises the aluminum laminate according to any one of <1> to <4 >.

< 6 > a blister package comprising: a sheet-shaped resin container including a storage section for storing an object to be stored; and a lid member attached to the resin container so as to cover the opening of the housing portion, the lid member including the aluminum laminate according to any one of the above items <1> -4 >.

Effects of the invention

According to the present invention, an aluminum laminate having good printability and excellent moisture resistance, and a packaging material and a blister package comprising the aluminum laminate can be provided.

Drawings

Fig. 1 is a schematic cross-sectional view of an example of the aluminum laminate of embodiment 1.

FIG. 2 is a schematic cross-sectional view of an example PTP according to embodiment 2.

FIG. 3 is a graph showing the piercing strength of the evaluation samples of examples 1 and 2 and comparative examples 2 to 4.

FIG. 4 is a graph showing the breaking distances of the evaluation samples of examples 1 and 2 and comparative examples 2 to 4.

Fig. 5 is an explanatory diagram of a calculation method of the pinhole diameter.

FIG. 6 is a graph showing the moisture permeability per day of the evaluation samples of examples 3 to 5 and comparative examples 5 and 6.

FIG. 7 is a graph showing the cumulative moisture permeability of the evaluation samples of examples 3 to 5 and comparative examples 5 and 6.

Detailed Description

< embodiment 1>

As shown in fig. 1, the aluminum laminate 1 according to the present disclosure includes at least a resin layer 30, a first aluminum foil 10 attached to one surface of the resin layer 30, and a second aluminum foil 20 attached to the other surface of the resin layer 30. Note that fig. 1 is a view schematically showing a cross section of the aluminum laminate 1, and the thickness of a part of the layers may be shown in a different scale from the other layers in consideration of the convenience of description (the same applies to fig. 2).

The first aluminum foil 10 and the second aluminum foil 20 are preferably each 30 μm or less in foil thickness. In general, a plurality of aluminum foils are rolled while being stacked between rolls to produce an aluminum foil having a foil thickness of 30 μm or less. In this case, the surface rolled while contacting with another aluminum foil becomes a matte surface, and the surface rolled while being arranged outside and contacting with the roller becomes a relatively glossy surface. When printing is performed on an aluminum foil, a matte surface is more suitable for printing than a glossy surface. This is because, since glare on the matte surface is small, visibility when printing is performed is excellent, and a printed matter that can reduce fatigue of the eyes of the observer can be obtained. Further, for example, when 3 aluminum foils are laminated and rolled, the variation in foil thickness of the aluminum foil in the middle becomes large, and it is often impossible to use the laminated and rolled aluminum foils. Therefore, it is difficult to manufacture an aluminum foil having a single-layer structure in which both surfaces facing outward are formed as dull surfaces by the conventional method.

As the first aluminum foil 10 and the second aluminum foil 20 of the present embodiment, materials having one surface formed with the dull surfaces 10A and 20A and the other surface formed with the glossy surface can be used. If the first aluminum foil 10 and the second aluminum foil 20 are bonded so that the surface opposite to the resin layer 30, that is, at least one of the two surfaces facing outward in the aluminum laminate 1 becomes a dull surface, the aluminum laminate 1 having a surface suitable for printing can be obtained. As shown in fig. 1, in the aluminum laminate 1 of the present embodiment, the first aluminum foil 10 and the second aluminum foil 20 are bonded so that the extinction surfaces 10A and 20A are disposed on both sides facing outward. In this way, the aluminum laminate 1 suitable for printing on both sides can be obtained.

The first aluminum foil 10 and the second aluminum foil 20 are preferably 6 μm or more in foil thickness. If the foil thickness is less than 6 μm, formability and handleability of the aluminum foil are deteriorated, and the frequency of occurrence of pinholes PH becomes extremely high. The aluminum laminate 1 preferably has a total foil thickness (excluding the thickness of the resin layer 30) of 30 μm or less, which is the sum of the foil thickness of the first aluminum foil 10 and the foil thickness of the second aluminum foil 20. For example, when the aluminum laminate 1 is used as a lid material for PTP, if the total foil thickness is larger than the lid material, the pressing force required for opening may increase, and good opening performance may not be ensured. In addition, even in the case of a single-layer aluminum foil, if the foil thickness is 30 μm or more, the frequency of generation of pinholes PH can be made extremely low, and therefore, if the total foil thickness of the aluminum laminate 1 is 30 μm or more, the advantage of producing an aluminum laminate by laminating a plurality of aluminum foils is reduced.

The first and second aluminum foils 10 and 20 may have substantially the same foil thickness or may have different foil thicknesses. In addition, the first and second aluminum foils 10 and 20 may have substantially the same hardness, or may have different hardnesses. For example, when the aluminum laminate 1 is used as a cover material for PTP, the opening property of the cover material can be further improved if the hardness and the foil thickness of each aluminum foil are appropriately adjusted and combined.

In the aluminum laminate 1, the first aluminum foil 10 and the second aluminum foil 20 are bonded to the resin layer 30. In other words, in the aluminum laminate 1, the resin layer 30 for bonding the first aluminum foil 10 and the second aluminum foil 20 is interposed between the two.

The resin layer 30 is formed of an adhesive resin that can exhibit sufficient bonding strength to the aluminum foil. The sufficient bonding strength here means that the peel strength with respect to the aluminum foil measured by a 180 ° peel test under the condition of 150mm/min is 3.0N/15mm or more, for example, with respect to a test piece having a width of 15 mm. Conventionally, a two-pack adhesive containing an isocyanate group has been used for bonding an aluminum foil. It is known that, in such an adhesive, a urethane bond is formed as shown in the following reaction formula (1) by adding a polyol to an isocyanate, and thereby, for example, a peel strength of at least 4.0N/15mm or more, usually about 8.0N/15mm is exhibited when measured under the above conditions.

[ chemical formula 1]

In the reaction formula (1), R and R' independently represent a hydrocarbon group, and n represents a natural number.

However, it is known that the reaction rate of water and isocyanate groups is higher than that of polyol and isocyanate groups, and when water is present in the environment where adhesion is performed, the reaction of the following reaction formula (2) proceeds preferentially to the reaction of the above reaction formula (1). As a result, when moisture is present during bonding, a urethane bond is not formed, and sufficient bonding strength cannot be obtained.

[ chemical formula 2]

n(OCN-R-NCO)+2n·H₂O→n·H₂N-R-NH₂+2n·CO₂↑ (2)

In the reaction formula (2), R represents a hydrocarbon group, and n represents a natural number.

When the first aluminum foil 10 or the second aluminum foil 20 is coated with an adhesive to bond the two aluminum foils 10 and 20 together in the production of the aluminum laminate 1, if any of the aluminum foils has a pinhole PH, moisture entering the pinhole PH reaches the adhesive, and no good bonding is achieved around the pinhole PH. Further, the carbon dioxide gas generated according to the above reaction formula (2) causes a partial bulge around the pinhole PH.

If a partial bulge occurs in the aluminum laminate 1, printing on the surface becomes an obstacle, and thus printability is impaired, and the aluminum laminate cannot be widely used in practical use. In order to obtain the aluminum laminate 1 having high practicability, it is necessary to form the resin layer 30 by selecting a resin that does not cause partial swelling even when bonding is performed in the presence of moisture and that can exhibit sufficient bonding strength. For example, a polyether adhesive is known as a one-pack adhesive, but the polyether one-pack adhesive has a lower adhesive strength than an isocyanate two-pack adhesive, has a peel strength of about 2.0N/15mm with respect to an aluminum foil, does not exhibit sufficient adhesive strength when used for bonding an aluminum foil, is easily peeled, and is not practical. Further, it is also conceivable to perform bonding by thermal lamination at 200 ℃ or higher using a high-temperature reactive adhesive, for example, but if a treatment at a high temperature is required, the production cost increases, and therefore, the adhesive cannot be widely used in practical use.

The present inventors have conducted extensive studies and, as a result, have found that a one-pack adhesive containing a polyhydroxyurethane resin is useful as an adhesive resin constituting the resin layer 30. Here, the polyhydroxyurethane resin refers to a polyurethane resin having a hydroxyl group in a side chain. Such a resin is sometimes referred to as a hydroxyl urethane resin, but is collectively expressed as a polyhydroxyurethane resin in the present specification. In the present invention, a polyhydroxyurethane resin having at least one hydroxyl group in a structural unit is particularly preferably used. The polyhydroxyurethane resin may have a structure represented by the following chemical formula (3), for example.

[ chemical formula 3 ]

In the chemical formula (2), R1 and R2 independently represent a hydrocarbon group, and n represents an integer of 1 to 50.

The polyhydroxyurethane resin as described above is a one-pack type containing no isocyanate group and does not react with moisture. In addition, bonding by dry lamination at a relatively low temperature is possible, and the first aluminum foil 10 and the second aluminum foil 20 can be bonded with sufficient strength without increasing the manufacturing cost. Specifically, when a 180 DEG peel test is performed on a test piece having a width of 15mm under the condition of 150mm/min and the peel strength with respect to an aluminum foil is measured, the peel strength can be at least 4.0N/15mm or more, usually 8.0N/15mm or more, and depending on the condition, 10.0N/15mm or more. Although the mechanism of adhesion between the polyhydroxyurethane resin and the aluminum foil is not clear, it is assumed that the polyhydroxyurethane resin may exhibit adhesion due to hydrogen bonds between a metal and hydroxyl groups contained in a large amount. The polyhydroxyurethane resin can be bonded with sufficient strength even when applied to either of the matte side and the glossy side of an aluminum foil and bonded thereto.

The polyhydroxyurethane resin as described above can be produced, for example, by reacting a five-membered cyclic carbonate compound and a polyfunctional amine compound in a molten state at 80 to 200 ℃. The cyclic carbonate compound can be produced, for example, by reacting an epoxy compound with carbon dioxide in the presence of a catalyst at 0 to 200 ℃ in a carbon dioxide atmosphere pressurized to about 0.1 to 1 MPa. That is, since the polyhydroxyurethane resin is a resin containing carbon dioxide, not an isocyanate compound produced using phosgene having high toxicity, it is preferable from the viewpoint of safety and environment.

The amount of the polyhydroxyurethane resin to be applied can be set to 0.5g/m²～7.0g/m²More preferably 2.0g/m²～5.0g/m². Within such a range, sufficient adhesive strength can be exhibited without excessively increasing the takt time and the like in dry lamination. In addition, if the thickness falls within such a range, the influence of the resin layer 30 on the flexibility, strength, and the like of the aluminum laminate 1 can be suppressed, and the aluminum laminate 1 exhibiting physical properties similar to those of a single-layer aluminum foil having a foil thickness equivalent to the total foil thickness can be obtained, which is also advantageous in terms of designing products.

The aluminum laminate 1 can be produced by applying the above-described polyhydroxyurethane resin to at least one surface of the first aluminum foil 10 and the second aluminum foil 20, drying the applied resin, and laminating and bonding 2 aluminum foils 10 and 20. Such dry lamination can be carried out, for example, under drying conditions of 80 to 120 ℃ for 5 to 30 seconds, and under pressure bonding conditions of 50 to 80 ℃ and 0.3 to 1.0 MPa. It is also assumed that the resin layer 30 formed when the polyhydroxyurethane resin is applied in the above-mentioned amount of application is about 1.5 μm to 6.0. mu.m.

The aluminum laminate 1 of the present invention is formed by bonding a first aluminum foil 10 and a second aluminum foil 20 to each other via a resin layer 30 containing a polyhydroxyurethane resin containing no isocyanate group. Therefore, the aluminum foils 10 and 20 are not affected by moisture when bonded. Therefore, even when the pinhole PH is formed in any of the aluminum foils 10 and 20, moisture does not affect the adhesion state, and gas is not generated to cause partial swelling. Therefore, the aluminum laminate 1 obtained by bonding 2 pieces of the aluminum foils 10 and 20 with sufficient strength can have a surface with good printability. Such an aluminum laminate 1 is required to have high moisture resistance and can be suitably used as a packaging material used for printing. Specifically, the film is particularly useful as a packaging material for pharmaceuticals that are inactivated by moisture absorption, foods and beverages that change their taste or flavor by moisture absorption, and industrial materials that change their functions or properties by moisture absorption. In the case of using the aluminum laminate as a packaging material, a heating step such as heat sealing is often performed, but it has been confirmed that the aluminum laminate 1 of the present invention hardly changes even when heated for a certain period of time in an oven at 180 ℃, for example, and has no problem in heat resistance.

As described above, the aluminum laminate 1 of the present embodiment includes: the resin layer 30 includes a resin layer 30, a first aluminum foil 10 bonded to one surface of the resin layer 30, and a second aluminum foil 20 bonded to the other surface of the resin layer 30, and the resin layer 30 includes at least a polyhydroxyurethane resin having at least one hydroxyl group in a structural unit.

The polyhydroxyurethane resin is one-pack room temperature curable type without containing an isocyanate group, and exhibits sufficient adhesion to an aluminum foil. According to the above configuration, by bonding the first aluminum foil 10 and the second aluminum foil 20 via the resin layer 30 containing a polyhydroxyurethane resin, it is possible to produce the aluminum laminate 1 having sufficient bonding strength without causing swelling of a portion due to carbon dioxide gas generated by a reaction of an isocyanate group and moisture. As a result, the aluminum laminate 1 having high moisture resistance and good printability can be obtained. In the present embodiment, the aluminum laminate 1 is produced by bonding 2 aluminum foils, i.e., the first aluminum foil 10 and the second aluminum foil 20, but it is needless to say that 3 or more aluminum foils may be bonded to produce an aluminum laminate. As the number of aluminum foil laminated pieces increases, a larger pinhole reduction effect can be obtained.

In the aluminum laminate 1 of the present embodiment, the polyhydroxyurethane resin forming the resin layer 30 contains a reaction product of a five-membered cyclic carbonate compound and an amine compound. Such a polyhydroxyurethane resin can be produced using a cyclic polycarbonate produced using carbon dioxide as a raw material, instead of an isocyanate compound produced using phosgene having high toxicity, and is therefore preferable from the viewpoint of environment and safety.

In the aluminum laminate 1 of the present embodiment, at least one of the first aluminum foil 10 and the second aluminum foil 20 is bonded to the resin layer 30 so that surfaces opposite to the resin layer 30 become the extinction surfaces 10A and 20A. With such a configuration, by manufacturing the aluminum laminate 1 so that at least one of the surfaces opposite to the resin layer 30, that is, the surfaces facing outward becomes the extinction surfaces 10A and 20A, the aluminum laminate 1 particularly suitable for printing on the surface can be obtained.

In the aluminum laminate 1 of the present embodiment, the foil thicknesses of the first aluminum foil 10 and the second aluminum foil 20 are both 6 μm or more, and the sum of the foil thicknesses of the first aluminum foil 10 and the second aluminum foil 20, that is, the total foil thickness is 30 μm or less. With this configuration, the frequency of occurrence of the pinholes PH in the two aluminum foils 10 and 20 can be suppressed to a certain degree, and the frequency of occurrence of the holes penetrating the entire aluminum laminate 1 can be reduced to a very small level, and the entire aluminum laminate can be made thinner. Thus, for example, when the aluminum laminate is used as a PTP lid, high moisture resistance and good opening property can be achieved at the same time.

The aluminum laminate 1 of the present embodiment can be used as a packaging material for pharmaceuticals, foods, beverages, or industrial materials. The aluminum laminate 1 is extremely low in the frequency of occurrence of pinholes PH penetrating therethrough, and therefore can be suitably used for packaging of objects to be packaged which require high moisture resistance as described above. Further, the aluminum laminate 1 has a surface having good printability without causing partial swelling or the like, and therefore can be suitably used as a packaging material used for printing.

< embodiment 2>

In the present embodiment, a PTP 200 having a lid member 201 including an aluminum laminate is exemplified. Fig. 2 is a sectional view schematically showing the structure of a PTP 200 of the present embodiment. PTP 200 is an example of a packaging material for storing a subject T (a pharmaceutical product such as a tablet or a capsule).

As shown in fig. 2, a PTP 200 of the present embodiment includes: a sheet-shaped resin container 2 including a housing portion 2A for housing an object T; and a lid member 201 attached to the resin container 2 so as to cover the opening 2B of the housing portion 2A.

The resin container 2 is a known resin container for PTP, and includes a transparent thermoplastic resin such as polyvinyl chloride, polyvinylidene chloride, polypropylene, and amorphous polyethylene terephthalate. The resin container 2 includes a sheet-like main body portion 2C and a housing portion 2A formed so as to bulge outward from the main body portion 2C. The storage section 2A is usually formed in plural for one resin container 2, but fig. 2 shows one storage section 2A for convenience of explanation. The housing section 2A is formed in a recessed shape having a space S for housing the object T therein, and has an opening 2B at a boundary portion with the main body section 2C. Although not particularly limited, the housing portion 2A is formed in a shape similar to the shape of the object T in a plan view. The resin container 2 is made of a sheet having a thickness of about 60 to 400 μm, which is processed into a predetermined shape.

The lid member 201 includes the first aluminum foil 10, the second aluminum foil 20, and the resin layer 30, which are similar to those of embodiment 1. Further, the first printing layer 211 is applied on the matte surface 10A of the first aluminum foil 10 by printing, and the heat-sealable adhesive layer 212 is formed on the first printing layer 211. Further, a second printing layer 221 is applied on the matte surface 20A of the second aluminum foil 20 by printing, and a superimposed layer 222 is formed on the second printing layer 221.

The first printing layer 211 displays information on the object T and other information, for example, and is provided by a known printing method using a known color printing ink. The first printed layer 211 is usually provided partially in a manner scattered on the matte surface 10A of the first aluminum foil 10. The first printing layer 211 is formed by, for example, gravure printing or the like to form a printing ink in which a binder resin contains a colorant (pigment) such as carbon black, phthalocyanine blue, phthalocyanine green, quinacridone, azo, or titanium dioxide. Such a first printed layer 211 can be recognized from the resin container 2 side.

The heat-sealable adhesive layer 212 is a layer for adhering the lid member 201 to the main body portion 2C of the resin container 2 and sealing the object to be stored T stored in the storage portion 2A of the resin container 2, and includes a known heat adhesive for PTP. Specifically, a thermal adhesive such as a polyester adhesive, a polypropylene adhesive, a vinyl chloride adhesive, or a vinyl chloride-vinyl acetate copolymer adhesive (vinyl chloride-vinyl acetate adhesive (trademark: ビ, Japanese) salt) is used as the thermal adhesive in the heat-sealable adhesive layer 212. In order to bond the heat-sealable adhesive layer 212 to the resin container 2 and perform thermal bonding at high temperature in the production of the PTP 200, the resin layer 30 of the aluminum laminate of the present invention has sufficient heat resistance as described in embodiment 1, and no problem occurs even when thermal bonding is performed at high temperature.

The second printing layer 221 displays information of the object T and other information basically in the same manner as the first printing layer 211, and is provided by a known printing method using a known color printing ink. The second printed layer 221 is provided partially or entirely so as to be scattered on the matte surface 20A of the second aluminum foil 20. That is, in the cover material 201, printing is performed on both outward surfaces of the first aluminum foil 10 and the second aluminum foil 20 disposed with the resin layer 30 interposed therebetween. Even if the pinholes PH are formed in either of the aluminum foils 10 and 20, the aluminum laminate of the present invention does not partially bulge, and since the surfaces to be printed are both the matte surfaces 10A and 20A, printing with excellent visibility can be performed on a surface having good printability.

The overprint layer 222 is a known transparent protective layer and is formed to cover the entire surface of the second print layer 221. Examples of the resin used for the overprint layer 222 include epoxy resin, melamine resin, nitrocellulose resin, butyral resin, acrylic resin, urethane resin, amino resin, polyethylene resin, polystyrene resin, polypropylene resin, polyester resin, vinyl chloride resin, polyvinyl alcohol, ethylene-vinyl acetate copolymer, ethylene-vinyl alcohol copolymer, ethylene-ethyl acrylate copolymer, and polyamide. These may be used alone or in combination of two or more.

As described above, the PTP 200 of the present embodiment includes: a sheet-shaped resin container 2 including a housing portion 2A for housing an object T; and a lid member 201 attached to the resin container 2 so as to cover the opening 2B of the housing portion 2A, and including an aluminum laminate. The aluminum laminate of the present invention has high moisture resistance and good printability, and is reduced in thickness. Therefore, by using such an aluminum laminate as the cover material 201, the PTP 200 having excellent opening property in addition to moisture resistance and printability can be obtained.

[ examples ] A method for producing a compound

The present invention will be described in more detail below with reference to examples. The present invention is not limited to the description of the examples.

<1. preparation of Strength evaluation sample >

The aluminum laminates and aluminum foils of examples 1 and 2 and comparative examples 1 to 4 were prepared as described below and used for strength evaluation tests.

[ example 1]

A total of 2 aluminum foils (made by UACJ, 1N30-H18, having a foil thickness of 6.6 μm) were prepared, one side of each foil being a glossy surface and the other side being matte surfaces 10A and 20A, respectively, as the first aluminum foil 10 and the second aluminum foil 20. On the glossy surface of the first aluminum foil 10, a coating amount was 3.3g/m using a bar coater²The coating was carried out using a polyhydroxyurethane resin adhesive (HPU C-3002, manufactured by Dai Highuai chemical Co., Ltd.). The first aluminum foil 10 coated with the adhesive was dried in an oven at 100 ℃ for 10 seconds, and then the second aluminum foil 20 was superimposed on the coated surface of the adhesive so that the glossy surface was in contact with the adhesive, and pressed at 60 ℃ and 0.4MPa to perform dry laminationAnd (6) mixing. This results in an aluminum laminate 1 having the basic structure shown in fig. 1, that is, an aluminum laminate 1 in which a first aluminum foil 10 is bonded to one surface of a resin layer 30 containing a polyhydroxyurethane resin and a second aluminum foil 20 is bonded to the other surface. The aluminum laminate 1 thus obtained was used as an evaluation sample in example 1.

[ example 2]

An aluminum laminate 1 in which the first aluminum foil 10 and the second aluminum foil 20 were bonded via the resin layer 30 containing a polyhydroxyurethane resin was obtained in the same manner as in example 1 except that aluminum foils (made by UACJ, 1N30-H18) each having a foil thickness of 12 μm were used as the first aluminum foil 10 and the second aluminum foil 20, and this was used as the evaluation sample of example 2.

Comparative example 1

Aluminum foils (made by UACJ K Co., Ltd.: 1N30-H18) each having a foil thickness of 12 μm were used as the first aluminum foil 10 and the second aluminum foil 20, and the coating weight was 4.7g/m on the glossy surface of the first aluminum foil 10²Except that an isocyanate-based two-pack adhesive (LX-500/KW-75 ═ 10/1, manufactured by japan ink corporation) was applied instead of the polyhydroxyurethane resin adhesive, an aluminum laminate in which the first aluminum foil 10 and the second aluminum foil 20 were bonded to each other through a resin layer was obtained in the same manner as in example 1, and this was used as an evaluation sample of comparative example 1.

[ comparative examples 2 to 4]

An aluminum foil (made of UACJ, 1N30-H18) having a foil thickness of 6.6 μm and a glossy surface on one side and a matte surface on the other side was used as an evaluation sample in comparative example 2.

An aluminum foil (made of UACJ, 1N30-H18) having a foil thickness of 12 μm and a glossy surface on one side and a matte surface on the other side was used as an evaluation sample in comparative example 3.

An aluminum foil (made of UACJ, 1N30-H18) having a foil thickness of 25 μm and a glossy surface on one side and a matte surface on the other side was used as an evaluation sample in comparative example 4.

Table 1 shows the outline of each strength evaluation sample.

[ TABLE 1]

1 polyhydroxy urethane resin-liquid type adhesive (HPU C-3002)

2 isocyanate two-pack adhesive (LX-500/KW-75)

<2> Strength evaluation test >

(2-1. evaluation of peeling Strength)

From the evaluation samples of example 2 and comparative example 1, 5 test pieces each having a width of 15mm were cut out. For each test piece, a 180 DEG peel test was performed under the condition of 150mm/min, and the peel strength (N/15mm) was measured. The test piece (5 pieces) of example 2 had an average peel strength of 12.0N/15mm, and the test piece of comparative example 1 had an average peel strength of 8.2N/15 mm.

(2-2. evaluation of the Burr Strength)

The puncture strength of the evaluation samples of examples 1 and 2 and comparative examples 2, 3 and 4 was measured in accordance with JIS Z1707 (2019). Table 2 shows the measurement results of the puncture strength and the breaking distance. Fig. 3 and 4 are graphs in which these results are plotted.

[ TABLE 2]

<3. examination of the results of the Strength evaluation test >

The evaluation samples of example 2 showed a high value of 12.0N/15mm on average in terms of peel strength. This value is higher than the average value (8.2N/15mm) of the evaluation samples of comparative example 1 which were prepared using an isocyanate-based two-pack adhesive and had a peel strength capable of withstanding practical use. As a result, it was confirmed that the first aluminum foil 10 and the second aluminum foil 20 were bonded to each other through the resin layer 30 containing a polyhydroxyurethane resin with sufficient strength to withstand practical use in the aluminum laminate 1 of the present invention.

As is clear from fig. 3 and 4, the aluminum laminates 1 of examples 1 and 2 were on the same level as the single-layer aluminum foil having a foil thickness corresponding to the total foil thickness of the aluminum laminates 1 and 2. When the aluminum laminate 1 of the present invention is used as a lid material for PTP, for example, it is considered that the strength and the opening property are equivalent to those of a conventionally used lid material including a single-layer aluminum foil, and the lid material can be sufficiently replaced. Further, since a correlation is observed between the total foil thickness of the aluminum laminate 1 and the foil thickness of the single-layer aluminum foil, it is considered that knowledge of the conventional single-layer aluminum foil can be utilized in designing a product using a packaging material of the aluminum laminate 1.

<4. preparation of sample for moisture permeability evaluation >

The aluminum laminates and aluminum foils of examples 3 to 5 and comparative examples 5 and 6 were prepared as described below and used in a moisture permeability evaluation test. The size of the pinhole PH included in each evaluation sample is represented by a "pinhole equivalent diameter" calculated as described below.

(calculation of pinhole equivalent diameter)

The shape of the pinholes PH generated in the aluminum foil is generally not constant depending on the cause of the occurrence, but as shown in fig. 5, a football shape elongated in the uniaxial direction (X direction in fig. 5) is often formed. The length (X) and the width (Y) perpendicular thereto at the longest diameter portion of the pinhole PH are measured using a laser microscope, and the diameter D of a circle having an area equal to the rectangular area (X × Y) is determined from the following equation (1), and is defined as the "pinhole equivalent diameter".

[ mathematical formula 1]

[ examples 3 to 5]

An aluminum laminate 1 was obtained in the same manner as in example 1 except that an aluminum foil having pinholes PH with a pinhole equivalent diameter of 110 μm was used as the first aluminum foil 10, and this was used as the evaluation sample of example 3.

An aluminum laminate 1 was obtained in the same manner as in example 1 except that an aluminum foil having pinholes PH with a pinhole equivalent diameter of 64 μm was used as the first aluminum foil 10, and this was used as the evaluation sample of example 4.

An aluminum laminate 1 was obtained in the same manner as in example 1 except that an aluminum foil having pinholes PH with a pinhole equivalent diameter of 24 μm was used as the first aluminum foil 10, and this was used as the evaluation sample of example 5.

Comparative examples 5 and 6

An aluminum foil (made by UACJ, a material: a 1N 30) having a foil thickness of 20 μm and a glossy surface on one side and a matte surface on the other side was prepared, and a laser beam was irradiated onto the aluminum foil using a device LP-Z130 manufactured by shin instrument SUNX, a fabb (ytterbium fiber laser) to form a pinhole PH under conditions of a spot size of 70 μm and an output of 13W, thereby obtaining an evaluation sample of comparative example 5. The pinhole equivalent diameter of the pinhole PH formed in the evaluation sample of comparative example 5 was 89 μm.

The evaluation sample of comparative example 6 was prepared in the same manner as in comparative example 5, except that the pinhole PH having a pinhole equivalent diameter of 114 μm was formed.

Table 3 shows the outline of each moisture permeability evaluation sample.

[ TABLE 3 ]

1 polyhydroxy urethane resin-liquid type adhesive (HPU C-3002)

<5. moisture permeability evaluation test >

For the evaluation samples of examples 3 to 5 and comparative examples 5 and 6, the following were set in accordance with JIS Z0208: 1976 moisture permeability test method (cup method) for moisture-proof packaging materials was used as a standard for measuring moisture permeability. Fig. 6 and 7 are graphs plotting the daily moisture permeability and the cumulative moisture permeability. Further, the value of the moisture permeability shown in the figure is 28.27cm²Converted into 1m in area²The obtained value is different from the moisture permeability in the actual package.

< 6. inspection of evaluation test result of moisture permeability >

As shown in FIGS. 6 and 7, in comparative examples 5 and 6, a constant amount of humidity was always transmitted, the cumulative moisture permeability increased in proportion to the passage of time, and the cumulative moisture permeability after 6 days had reached about 9g/m²Or about 14g/m²On the other hand, in all of the evaluation samples of examples 3 to 5, the moisture permeability was changed to a very small level, and the cumulative moisture permeability after 6 days was kept at less than 2g/m². It is understood that, in the aluminum laminate 1 of the present invention, even when the pinholes PH are generated in one of the aluminum foils (the first aluminum foil 10), the aluminum laminate can maintain good moisture resistance. The evaluation samples of examples 3 to 5 all included a region existing around the pinhole PH of the first aluminum foil 10, and no partial swelling was observed.

Description of the symbols

1 … aluminum laminate,

10 … a first aluminum foil,

20 … second aluminum foil,

10A, 20A … dull surfaces,

30 … resin layer,

200…PTP、

2 … resin container,

2A … accommodating part,

2B … opening part,

2C … main body part,

201 … cover material,

211 … a first printed layer,

212 … heat sealable adhesive layer,

221 … second printing layer,

222 … laminated layer,

D … (pinhole equivalent) diameter,

T … stored item.