JP2018099814A - Laminate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a packaging material for imparting a container in which a laminated structure on the furthermore content side than a barrier layer does not become brittle, even when a content selected from a strongly acid content and a content containing a branched higher alcohol is filled thereinto.SOLUTION: In a laminate having, in this order, an outer layer 1, a first adhesion layer 2, an aluminum layer 3, a second adhesion layer 4, a third adhesion layer 5 and a sealant layer 6, the second adhesion layer 4 contains an ethylene-methacrylic acid copolymer, and the third adhesion layer 5 contains an ethylene-acrylic acid copolymer.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a laminate.

  As a material constituting a container for storing medicine, cosmetics, food, toothpaste, etc., for example, a plurality of films having various functions including barrier properties in order to protect the contents from environmental elements such as moisture and oxygen The laminated body of is known.

  As the laminate, for example, a laminate in which a surface resin layer and a sealant layer having a heat seal function are laminated on both surfaces of a barrier layer (typically an aluminum layer) for protecting contents is known. ing. As a container using such a laminate, for example, a tube container is known. The tube container is formed by, for example, forming a shoulder portion having a screw for sealing on a barrel portion formed by sealing the above-described laminated body into a cylindrical shape and screwing a cap to the shoulder portion, and then opening an open end of the barrel bottom portion. Can be manufactured by filling the contents and end sealing the open end.

  As a prior art about the laminated body which used the aluminum layer as a barrier layer for the protection of the contents, the technique of patent documents 1-4 is proposed, for example.

  Example 1 of Patent Document 1 includes a surface resin layer, an aluminum layer, and a linear low density polyethylene (LLDPE) having a thickness of 30.5 μm that is a sealant layer, and the space between the aluminum layer and the sealant layer is ethylene. -A laminate bonded with an acrylic acid copolymer (EAA) is disclosed. The laminate of Patent Document 1 is assumed to be applied to toothpaste and the like.

  Example 1 of Patent Document 2 includes LLDPE, which is a surface resin layer, an aluminum layer, and a sealant layer, and the aluminum layer and the sealant layer are bonded by an ethylene-methacrylic acid copolymer (EMAA). A laminated body for a tube is disclosed.

  In Example 1 of Patent Document 3, a polyethylene terephthalate (PET) layer is laminated on both sides of an aluminum layer, and a two-component curable urethane system is provided between one of the PET layers and an ionomer layer having a thickness of 40 μm. A packaging material bonded with a special anchor coating agent is disclosed.

  In Example 1 of Patent Document 4, after laminating an LLDPE layer on a printed layer formed on one side of a PET substrate, an aluminum foil is laminated on the LLDPE layer via EMAA, and then the aluminum foil There is disclosed a tube container formed from a laminate formed by further laminating an LLDPE layer on the other side of the PET base material and laminating the LLDPE layer on the other surface of the PET base material via a polyethylene resin.

JP-A-3-647 JP 2004-167975 A JP-A-11-254595 JP 2010-235177 A

  The container formed from the said well-known laminated body shows the outstanding sealing performance and filling storage stability in a weakly acidic-alkaline region. However, in the strongly acidic region, the contents may permeate the sealant layer and stay between the aluminum layer, and the laminated structure on the contents side of the aluminum layer may be weakened.

  In particular, in the field of hair dyeing, a new product category called hair color treatment (hair manicure) products has emerged and is spreading apart from the conventional hair color products. Hair color treatments vary greatly in pH depending on the type, and there are strongly acidic products with a pH of 4.0 or less.

  The hair color treatment may further contain a branched higher alcohol in order to develop functions such as an emollient, an emulsifier, and a quality improver. When a container formed of a known laminate is filled with a content containing a branched higher alcohol, even if the acidity of the content is not so high, the same as in the case of the above strongly acidic content Infiltration and stagnation may occur, and the laminated structure may be weakened.

  Interestingly, the permeation and retention of the higher alcohol is a phenomenon peculiar when the long-chain alkyl group of the higher alcohol has a branched structure. In the case of the content containing only what has a linear alkyl group as a higher alcohol, such a problem does not arise.

The present invention has been made to solve the above problems. Therefore, the object of the present invention is to
Even when filled with a content selected from strong acidic content and content containing branched higher alcohol, as represented by hair color treatment, the laminated structure on the content side of the barrier layer is weakened. It is to provide a packaging material that gives a container that does not.

  The present invention achieves the above object by the means summarized below.

[1] It has an outer layer, a first adhesive layer, an aluminum layer, a second adhesive layer, a third adhesive layer, and a sealant layer in this order,
The second adhesive layer contains an ethylene-methacrylic acid copolymer;
The third adhesive layer contains an ethylene-acrylic acid copolymer;
Laminated body.

  [2] The laminate according to [1], wherein the sealant layer contains linear low-density polyethylene.

  [3] A container comprising the molded body of the laminate according to [1] or [2].

  [4] The container according to [3], which is used for filling a content selected from hair care products, cosmetics, and pharmaceuticals.

  [5] The container according to [4], wherein the content is selected from a content having a pH of 2.0 or more and 4.0 or less and a content containing a branched higher alcohol.

[6] In the container according to [3],
Filled with contents selected from hair care products, cosmetics and pharmaceuticals,
Filling container.

  [7] The filled container according to [6], wherein the content is selected from a content having a pH of 2.0 or more and 4.0 or less and a content containing a branched higher alcohol.

  Even when the laminate of the present invention is filled with a strongly acidic content or a content containing a branched higher alcohol, the laminate structure on the content side of the aluminum layer does not become weak. Therefore, the laminate of the present invention can be suitably used for producing a container filled with a content selected from a wide pH range content containing strong acidity and a content containing a branched higher alcohol. .

FIG. 1 is a cross-sectional view for explaining the structure of the laminate of the present invention.

<Laminate>
The laminate of the present invention has an outer layer, a first adhesive layer, an aluminum layer, a second adhesive layer, a third adhesive layer, and a sealant layer in this order,
The second adhesive layer contains an ethylene-methacrylic acid copolymer;
The third adhesive layer contains an ethylene-acrylic acid copolymer.

  The laminate of the present invention exhibits high resistance to both strongly acidic contents and contents containing branched higher alcohols by taking the above-described configuration. The reason why the laminate of the present invention exhibits such an effect is not clear. However, the present inventors speculate as follows. However, the present invention is not limited to a specific theory.

  The third adhesive layer in the laminate of the present invention contains an ethylene-acrylic acid copolymer (EAA). Unlike an ethylene-methacrylic acid copolymer (EMAA) adhesive resin in a known laminate, EAA does not have a methyl group that is directly bonded to a polymer chain, so its properties are closer to that of polyethylene. Therefore, EAA is preferably considered to be excellent in affinity with a sealant layer containing LLDPE. Therefore, strong affinity acts between both layers, and it is assumed that the laminate strength and the like are not impaired even under acidic conditions. In fact, the container manufactured from the laminate using the third adhesive layer containing EAA has a weaker laminated structure on the contents side than the aluminum layer even when the strongly acidic contents are stored. And high heat seal strength and high laminate strength are maintained over a long period of time.

  About the case where the content contains branched higher alcohol, it is guessed as follows.

  Since LLDPE preferably contained in the sealant layer has an alkyl group directly bonded to a polymer chain composed of an ethylene chain, it has a structure close to that of a branched alkyl group of a branched higher alcohol. Therefore, the branched higher alcohol has a high affinity with the sealant layer. Therefore, when a container made of a known laminate is filled with a content containing a branched higher alcohol, the content penetrates the sealant layer and reaches the adhesive layer, attacking the hydrogen bond between the aluminum layer / adhesive layer. It is considered that the laminated structure is weakened by separating the hydrogen bonds.

  On the other hand, in the laminate of the present invention, the second adhesive layer contains EMAA having a methyl group in the polymer chain. The electron donating property of the methyl group in the second adhesive layer is considered to increase the electron density of the carbonyl moiety involved in the hydrogen bond between the aluminum layer / adhesion layer and to strengthen the bonding force of the hydrogen bond. Even if the contents penetrate the sealant layer to reach the adhesive layer and attack the hydrogen bond between the aluminum layer / adhesive layer, the strengthened hydrogen bond does not dissociate. It is inferred that the laminate of the present invention having two adhesive layers has a high resistance to branched higher alcohols.

  Furthermore, since the EMAA in the second adhesive layer and the EAA in the third adhesive layer are close in structure, the adhesive strength between the two layers is high. Therefore, the interlayer adhesive strength of the laminate of the present invention is as a whole of the laminate. Will be extremely high.

FIG. 1 is a cross-sectional view for explaining a typical structure of the laminate of the present invention. 1 has an outer layer 1, a first adhesive layer 2, an aluminum layer 3, a second adhesive layer 4, a third adhesive layer 5, and a sealant layer 6 in this order.
The second adhesive layer 4 contains an ethylene-methacrylic acid copolymer,
The third adhesive layer 5 contains an ethylene-acrylic acid copolymer.

  Hereinafter, the laminate of the present invention will be described in detail focusing on preferred embodiments thereof.

[Outer layer]
The outer layer in the laminate of the present embodiment can be made of resin, for example. The outer layer may be a single layer composed of one resin layer or a laminate composed of a plurality of resin layers. Printing may be performed on one or more of the layers constituting the outer layer.

  The outer layer is present in the laminated body in order to give the laminated body of the present embodiment the strength necessary for the laminated body, the waist required during processing, and the like. As a material constituting the outer layer, for example, a polyester resin film, a polyamide resin film, a polyolefin resin film, or the like may be used.

  As said polyester-type resin film, the film which consists of a polyethylene terephthalate etc. can be mentioned, for example. As said polyamide-type resin film, the film which consists of various nylon etc. can be mentioned, for example. Examples of the polyolefin resin film include films made of polyethylene resin, polypropylene resin, cyclic polyolefin resin, and the like. These films may be subjected to biaxial stretching in order to further improve the heat resistance and impact resistance of the resulting laminate.

  The outer layer in the present embodiment may be a single layer or multilayer film composed of a polyester resin film, a polyamide resin film, a polyolefin resin film, or the like. A laminated film having a surface resin layer made of a resin having heat sealability may be used on the material, or a white film or the like may be used as a part of the outer layer.

  As the outer layer, a laminated film having the above-mentioned surface resin layer on the substrate and the surface resin layer as the outermost layer is formed. When the laminate is molded into a container shape, the surface resin layer becomes a sealant. This is preferable in that it can be fused with the layer to form a cylindrical body.

  Examples of the resin having heat sealability include low density polyethylene (LDPE), medium density polyethylene (MDPE), high density polyethylene (HDPE), linear low density polyethylene (LLDPE), polypropylene (PP), and ethylene-acetic acid. Vinyl copolymer (EVA), ionomer resin, ethylene-acrylic acid copolymer (EAA), ethylene-acrylic acid ester copolymer (for example, ethylene-ethyl acrylate copolymer), ethylene-methacrylic acid copolymer ( EMAA), ethylene-methacrylic acid ester copolymer (for example, ethylene-ethyl methacrylate copolymer), and the like.

  When using a laminated film having a surface resin layer made of a resin having heat sealability on the base material as the outer layer, the thickness of the base material may be, for example, 5 μm or more, 10 μm or more, or 12 μm or more. , 100 μm or less, 50 μm or less, 30 μm or less, or 25 μm or less.

  When a layer made of an ethylene-based resin is used as the surface resin layer in the laminated film, the thickness of the surface resin layer is, for example, 20 μm or more from the viewpoint of good workability, surface slipperiness, heat sealability, and the like. It can be 30 μm or more, or 40 μm or more, for example, 100 μm or less, 80 μm or less, or 60 μm or less.

  The thickness of the outer layer in the laminate of the present embodiment (when the outer layer is composed of a plurality of layers, the total thickness thereof) can be, for example, 5 μm or more, 10 μm or more, or 15 μm or more, for example, 500 μm. Hereinafter, it can be 300 μm or less, or 200 μm or less.

  What is supplied as a film may be used for an outer layer.

[First adhesive layer]
The 1st adhesion layer in the layered product of this embodiment is a layer for joining the above-mentioned outer layer and the below-mentioned aluminum layer. The first adhesive layer can be appropriately selected by those skilled in the art depending on the method of manufacturing the laminate. For example, as a bonding method between the two layers when the outer layer and the aluminum layer are formed in advance in a film shape, for example,
Dry laminating method using dry laminating adhesive;
Lamination method using other adhesives;
Examples thereof include a sand laminate method in which an adhesive resin is extruded between the outer layer and the aluminum layer by a melt extrusion method.

  As an example of forming the outer layer by a melt extrusion method, for example, a method of appropriately forming an adhesive resin and an outer layer on the aluminum layer by a melt extrusion method can be given.

  Examples of the dry laminate adhesive include urethane adhesives, polyester adhesives, titanate adhesives, imine adhesives, butadiene adhesives, and olefin adhesives. Of these, thermosetting adhesives are preferable, and urethane adhesives are particularly preferable.

  Examples of the other adhesives include two-component curable polyurethane adhesives, polyvinyl acetate adhesives, polyacrylate adhesives, cyanoacrylate adhesives, and ethylene copolymer adhesives. Can do.

Examples of the adhesive resin suitable for forming by the melt extrusion method include ionomer resins and olefinic (co) polymers. Among them, preferred examples include, for example,
Low density polyethylene (LDPE), medium density polyethylene (MDPE), high density polyethylene (HDPE), linear low density polyethylene (LLDPE), polypropylene (PP);
Ethylene-vinyl acetate copolymer;
Ethylene-acrylic acid copolymer (EAA), ethylene-methacrylic acid copolymer (EMAA), ethylene-ethyl acrylate copolymer (EEA), ethylene-methyl acrylate copolymer (EMA), ethylene-methacrylate copolymer Ethylene- (meth) acrylic monomer copolymers such as (EMAA);
Etc.

  When forming the first adhesive layer by melt extrusion, the thickness of the first adhesive layer can be, for example, 5 μm or more, 10 μm or more, or 20 μm or more, and is 100 μm or less, 75 μm or less, or 50 μm or less. It can be.

[Aluminum layer]
In order to protect the contents, the aluminum layer in the laminate of the present embodiment is used to improve barrier properties such as light shielding properties, oxygen shielding properties, water vapor shielding properties, and fragrance retaining properties in the laminate.

  The thickness of the aluminum layer can be appropriately set from the viewpoints of sufficient barrier properties, high-grade metallic luster, more difficult to wrinkle, and good handling when used as a container. For example, it can be 5 μm or more, 6 μm or more, 8 μm or more, or 10 μm or more, and can be 50 μm or less, 40 μm or less, 30 μm or less, or 25 μm or less.

  As the aluminum layer, a commercially available aluminum foil having a desired thickness may be appropriately selected and used.

[Second adhesive layer]
The 2nd adhesion layer in the layered product of this embodiment is a layer for joining the above-mentioned aluminum layer and the below-mentioned sealant layer with the below-mentioned 3rd adhesion layer.

  The 2nd adhesion layer in the layered product of this embodiment contains ethylene-methacrylic acid copolymer (EMAA). The second adhesive layer in the laminate of the present embodiment may be a layer made only of EMAA, or may contain another resin together with EMAA. Examples of other resins used here include EAA and ethylene-methyl methacrylate copolymer (EMMA). The second adhesive layer may contain 50% by weight or more, 60% by weight or more, 70% by weight or more, 80% by weight or more, 90% by weight or more, or 95% by weight or more, and is a layer made of only EMAA. It may be.

  The thickness of the second adhesive layer in the laminate of the present embodiment can be, for example, 20 μm or more, 30 μm or more, or 50 μm or more, for example, 150 μm or less, 100 μm or less, or 75 μm or less.

[Third adhesive layer]
The 3rd adhesion layer in the layered product of this embodiment is a layer for joining the above-mentioned aluminum layer and the below-mentioned sealant layer with the above-mentioned 2nd adhesion layer.

  The 3rd adhesion layer in the layered product of this embodiment contains ethylene-acrylic acid copolymer (EAA). The third adhesive layer in the laminate of the present embodiment may be a layer made of only EAA, or may contain another resin together with EAA. As other resin used here, EMAA, EMMA, etc. can be mentioned, for example. The third adhesive layer may contain 50% by weight or more, 60% by weight or more, 70% by weight or more, 80% by weight or more, 90% by weight or more, or 95% by weight or more, and is a layer made of only EAA. It may be.

  The thickness of the 3rd adhesion layer in the layered product of this embodiment can be 5 micrometers or more, 10 micrometers or more, or 15 micrometers or more, for example, can be 150 micrometers or less, 100 micrometers or less, or 75 micrometers or less.

[Sealant layer]
The sealant layer in the laminate of this embodiment preferably has heat sealability. This sealant layer is heat-sealed with the surface resin layer in the outer layer to form, for example, a cylindrical body constituting the body part of the tube container, and / or heat-seal the sealant layers facing each other in the cylindrical body. By doing so, for example, it has a function of sealing the bottom of the tube container.

  Examples of the resin constituting the sealant layer include polypropylene (PP), ethylene-vinyl acetate copolymer (EVA), ionomer resin, ethylene-acrylic acid copolymer (EAA), and ethylene-methacrylic acid copolymer (EMAA). ) And polyethylene. Polyethylene is preferable, and specifically, for example, HDPE, MDPE, LDPE, LLDPE and the like may be used. When the content is a semi-fluid substance such as cream, LLDPE is preferable from the viewpoint of imparting good low-temperature heat sealability, foreign matter sealability, and processability.

  The sealant layer may be a single layer composed of one resin layer or a laminate composed of a plurality of resin layers. When the sealant layer is a laminate composed of a plurality of resin layers, the resins constituting each layer may be the same as or different from each other.

  The sealant layer may be formed by an appropriate film forming method such as a melt extrusion method or a co-extrusion method using a resin supplied in the form of pellets, or the resin supplied as a film is used as it is. May be. However, in order to form a laminate that can form a stronger bond with the above-described third adhesive layer and that does not easily deteriorate the laminate strength even under acidic conditions, the sealant layer is formed by a melt extrusion method. It is preferable to form a film.

  The thickness of the sealant layer in the laminate of the present embodiment may be, for example, 20 μm or more, 30 μm or more, 40 μm or more, or 50 μm or more, and may be 150 μm or less, 100 μm or less, or 90 μm or less.

<Method for producing laminate>
The laminated body of this embodiment can be manufactured by a well-known method other than using each said layer, or adding the appropriate change by those skilled in the art to this.

In manufacturing the laminate of the present embodiment, the outer layer, the first adhesive layer, the aluminum layer, the second adhesive layer, the third adhesive layer, and the sealant layer described above are separately prepared, and these are prepared. Or by pasting together; or
The aluminum layer and the unit resin layer constituting each of the other layers are laminated in any order, and as a result, the outer layer, the first adhesive layer, the aluminum layer, the second adhesive layer, the third adhesive layer, And you may obtain the laminated body by which the sealant layer was laminated | stacked in this order.

  Each of the second adhesive layer and the third adhesive layer in the laminate of the present embodiment can be formed by a film forming method such as a melt extrusion method using a resin supplied in the form of a pellet or the like. preferable.

  The second adhesive layer and the third adhesive layer; the third adhesive layer and the sealant layer; or the second adhesive layer, the third adhesive layer, and the sealant layer may be formed by a coextrusion method. This is a preferred embodiment in the form.

  If the thickness of the sealant layer in the laminate of the present embodiment is 70 μm or more, the desired heat seal strength is stably expressed even if the processing temperature at the time of forming the sealant layer by the melt extrusion method varies somewhat. It may be preferable.

<Container and its manufacturing method>
A container can be manufactured using the laminated body of this embodiment demonstrated above. The container of this embodiment includes a molded body of a laminate.

  The container including the molded body of the laminate of the present embodiment can be used by filling, for example, hair care products, cosmetics, pharmaceuticals, and the like as contents. Specific examples of hair care products include, for example, hair color treatments; specific examples of cosmetics include, for example, face wash, lotion, lotion, etc .; specific examples of pharmaceuticals include, for example, creams, ointments, Examples thereof include liquid agents, gel agents, lotion agents, and the like.

  When the above content is selected from a content having a pH of 2.0 or more and 4.0 or less and a content containing a branched higher alcohol, the effect expected by the present invention is maximized. And preferred.

  Branched higher alcohols are preferably contained in recent hair color treatments in order to develop functions such as emollients, emulsifiers and quality improvers. Examples of the branched higher alcohol include alcohols having a branched alkyl group having 12 or more carbon atoms. The branched alkyl group in the branched higher alcohol may have 14 or more carbon atoms, and may have 30 or less, 28 or less, 26 or less, 24 or less, 22 or less, or 20 or less. Specific examples of the branched higher alcohol include hexyl decanol and octyl decanol.

  The container of this embodiment typically has the component name of the contents printed on the outer surface of the container, or a label that describes the component name of the contents on the outer surface of the container. used.

  Hereinafter, the manufacturing method of a container is demonstrated taking the case of manufacturing a tube container as an example.

  The tube container using the laminated body of the present embodiment includes, for example, a process of cutting the laminated body into an appropriate size, sealing a side part to form a cylindrical body part, and forming a shoulder part and a lip part. Can be manufactured by. A suitable cap is attached to this container, and the contents are filled, and then the bottom is sealed, so that it can be used as a tube-type sealed container. The order of performing the above steps can be arbitrarily changed.

  For example, heat seal, hot air, and ultrasonic seal can be used for the side and bottom seals, respectively, and a high-frequency continuous oscillation type seal can be used.

  In the following Examples and Comparative Examples, the following commercially available products were used as resins in each layer. For materials with the letter “f” following the capital letter of the alphabet, materials supplied in the form of films are used as they are. For materials without the letter “f”, the raw materials supplied as pellets are melt-extruded (back lamination method or It was formed into a layer by a sand lamination method. “ALf” indicates an aluminum foil, and a commercially available product made by UACJ having a predetermined thickness was used as it was. In the following description, the number shown immediately after the material symbol is the thickness in μm.

PETf: Polyethylene terephthalate film (manufactured by Toyobo Co., Ltd., product name “E5100”, thickness 12 μm and 25 μm, both-side corona discharge treatment)
Milky white HDPEf: Milky white high-density polyethylene film (manufactured by Aicello Co., Ltd., product name “FA-550 white”, thickness 60 μm)
LLDPE: linear low density polyethylene (manufactured by Prime Polymer Co., Ltd., product name “SP15101D”, pellet)
LDPE: Low density polyethylene (Asahi Kasei Polychemicals Co., Ltd., product name “M1880E”, pellet)
EAA: ethylene-acrylic acid copolymer (manufactured by Nippon Polyethylene Co., Ltd., product name “A201M”, pellets)
EMAA: ethylene-methacrylic acid copolymer (Mitsui / Dupont Polychemical Co., Ltd., product name “N0908C”, pellets)

<Manufacture of laminates>
[Example 1]
An anchor coating agent was applied on the surface of PETf25 as an outer layer. ALf20 is prepared as an aluminum layer, and sand lamination is performed while extruding EMAA as the first adhesive layer between the PETf25 and the anchor coating agent application surface, and PETf12, EMAA30 (first adhesive layer), and ALf20 are A laminate a having a three-layer structure laminated in this order was obtained. On the ALf side surface of this laminate a, an EMAA layer (EMAA55) having a thickness of 55 μm was formed as a second adhesive layer by an extrusion method to obtain a laminate b having a four-layer structure. Next, an EAA layer (EAA50) having a thickness of 50 μm was formed as a third adhesive layer on the surface of the laminate b on the EMAA 55 side by an extrusion method to obtain a laminate c having a five-layer structure.

Subsequently, an LDPE layer (LDPE50) having a thickness of 50 μm is formed as a sealant layer on the surface of the laminate c on the EAA 50 side by an extrusion method, thereby obtaining the laminate of Example 1 having the following layer configuration. It was.
PETf25 / EMAA30 / ALf20 / EMAA55 / EAA50 / LLDPE50 (6-layer configuration)

[Example 2]
A laminated body of Example 2 having the following layer configuration is obtained in the same manner as in Example 1 except that the thickness of the EAA layer as the third adhesive layer is 30 μm and the thickness of the LLDPE as the sealant layer is 70 μm. It was.
PETf25 / EMAA30 / ALf20 / EMAA55 / EAA30 / LLDPE70 (6-layer configuration)

[Example 3]
The laminate of Example 3 having the following layer configuration similar to that of Example 2 except that EAA 30 as the third adhesive layer and LLDPE 70 as the sealant layer were formed by coextrusion. Obtained.
PETf25 / EMAA30 / ALf20 / EMAA55 / EAA30 / LLDPE70 (6-layer configuration)

[Example 4]
A laminate of Example 4 having the following layer configuration was obtained in the same manner as Example 3 except that the thickness of the EAA layer as the third adhesive layer was 15 μm.
PETf25 / EMAA30 / ALf20 / EMAA55 / EAA15 / LLDPE70 (6-layer structure)

[Comparative Example 1]
An anchor coating agent was applied on the surface of PETf25. ALf20 is prepared, sand lamination is performed while extruding EMAA between the above-mentioned PETf25 and the anchor coating agent application surface, and a three-layer structure in which PETf25, EMAA30 (first adhesive layer) and ALf20 are laminated in this order. Body a was obtained. An EMAA layer (second adhesive layer, EMAA55) having a thickness of 55 μm was formed on the surface of the laminate a on the ALf20 side by extrusion to obtain a laminate b. Next, after applying an anchor coating agent on the surface of the laminate b on the PETf25 side, sand lamination is performed while extruding LDPE between the milky white HDPEf60, and milky white HDPEf60, LDPE20, PETf25, EMAA30, ALf20, and EMAA55 A laminate c having a six-layer structure was obtained in this order.

  Subsequently, an LDPE layer (LDPE50) having a thickness of 50 μm is formed on the milky white HDPEf60 side surface of the laminate c by the extrusion method to obtain a laminate d, and then extruded onto the EMAA55 side surface of the laminate d. A laminate of Comparative Example 1 was obtained by forming an LLDPE layer (sealant layer, LLDPE45) having a thickness of 45 μm by the method. In this laminate, the third adhesive layer is not formed.

The layer structure of the laminate of Comparative Example 1 is as follows.
LDPE50 / milk white HDPEf60 / LDPE20 / PETf25 / EMAA30 / ALf20 / EMAA55 / LLDPE45 (8-layer structure)

[Comparative Example 2]
ALf25 was laminated on PETf25 via a two-component reaction curable adhesive (first adhesive layer), and this was used as laminate a. An EAA layer (third adhesive layer, EAA30) having a thickness of 30 μm was formed on the surface of the laminate a on the ALf25 side by an extrusion method to obtain a laminate b. Then, an LLDPE layer (sealant layer, LLDPE 70) having a thickness of 70 μm was formed on the surface of the laminate b on the EAA 30 side by an extrusion method under a die temperature of 300 ° C., thereby obtaining a laminate of Comparative Example 2. . In this laminate, the second adhesive layer is not formed.

The layer structure of the laminate of Comparative Example 2 is as follows.
PETf12 / 2 liquid reaction curable adhesive / ALf25 / EAA30 / LLDPE70 (5 layers configuration)

  The layer structures of the laminates of Examples 1 to 4 and Comparative Examples 1 and 2 obtained above are summarized in Table 1 below.

<Evaluation of laminate>
Using each of the laminates obtained in the above examples and comparative examples, making a plurality of three-side seal bags with an inner dimension of MD100 mm x TD50 mm with the sealant layer side inside, each hair color listed in Table 1 After filling with 25 g of the treatment, the opening side was sealed to prepare a hair color treatment filling bag. The filled bag was stored at 50 ° C. for 1 month. The peel strength between each layer before and after storage was measured by the following method.

  A plurality of strip-shaped test pieces having a length of 100 mm and a width of 15 mm were cut out from the filled bag after one month storage so that the MD direction was the long side direction. The aluminum layer / second adhesive layer, the second adhesive layer / third adhesive layer, or the third adhesive layer / sealant layer inside the aluminum layer of these test pieces is slightly peeled and sandwiched between chucks ( Using a strograph “VES10” manufactured by Toyo Seiki Seisakusho, T-peel strength was measured at a gripping movement speed of 300 mm / min (JIS K6854). The evaluation results are shown in Table 2.

Abbreviations for hair color treatments in Table 2 represent the following products, respectively.
A: Kenlux (manufactured by Intercosme)
B: Teyara (made by Shiseido Co., Ltd.)
C: Cover gray (manufactured by Daime Healthcare)
D: Tenstar henna color treatment (manufactured by Sanpo Shoji Co., Ltd.)
E: Secret color natural treatment (Cosmex Roland Co., Ltd.)

  The pH value in Table 2 is a value measured using a hair color treatment sampled by 5 g each using an AP-20 waterproof pH meter manufactured by A & D.

  In Table 2, “Unpeelable” indicates that no peeling occurred under the above test conditions. “Other interlayer peeling” indicates that an interlayer different from the evaluation target interlayer peeled. “Peeling before test” means that in the laminate after storage for 1 month under the above conditions, the adhesion between the evaluation target layers was already impaired, and a meaningful measurement value was not obtained by the peeling test. Indicates.

  As understood from Table 2, the laminate of the comparative example has an aluminum layer / adhesive layer and a high acid content having a pH of 4.0 or less or a content containing a branched higher alcohol. The peel strength of at least one of the adhesive layer / sealant layer is impaired.

  On the other hand, in the laminate of this embodiment, the peel strength between layers is impaired regardless of whether the strongly acidic content having a pH of 4.0 or less and the content containing a branched higher alcohol are stored. To a small extent, it showed good resistance to these contents.

DESCRIPTION OF SYMBOLS 1 Outer layer 2 1st contact bonding layer 3 Aluminum layer 4 2nd contact bonding layer 5 3rd contact bonding layer 6 Sealant layer

Claims (7)

It has an outer layer, a first adhesive layer, an aluminum layer, a second adhesive layer, a third adhesive layer, and a sealant layer in this order,
The second adhesive layer contains an ethylene-methacrylic acid copolymer;
The third adhesive layer contains an ethylene-acrylic acid copolymer;
Laminated body.   The laminate according to claim 1, wherein the sealant layer contains linear low-density polyethylene.   A container comprising the molded body of the laminate according to claim 1.   4. Container according to claim 3, used for filling a content selected from hair care products, cosmetics and pharmaceuticals.   The container according to claim 4, wherein the contents are selected from contents having a pH of 2.0 or more and 4.0 or less and contents containing a branched higher alcohol. In the container according to claim 3,
Filled with contents selected from hair care products, cosmetics and pharmaceuticals,
Filling container.   The filled container according to claim 6, wherein the content is selected from a content having a pH of 2.0 or more and 4.0 or less and a content containing a branched higher alcohol.

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