JP6388192B2 - Deep-drawing laminate and deep-drawing container - Google Patents

Description

  The present invention relates to a deep drawing laminate, and more particularly to a deep drawing laminate comprising a base layer, a barrier layer, and a heat seal layer in this order. The present invention also relates to a deep-drawing container made of the deep-drawing laminate.

  BACKGROUND OF THE INVENTION Deep-drawn containers that are manufactured by deep-drawing a laminate in which a plurality of types of films are laminated are widely used for retort containers that package retort foods. In deep drawing, the laminated body is stretched, and the laminated body is brought into close contact with a predetermined mold using vacuum, pneumatic pressure, or the like to manufacture a deep drawn molded container having a predetermined shape.

  Conventionally, a deep drawing laminate in which an aluminum foil is sandwiched between plastic films has been used for manufacturing deep drawing containers. However, in order to reduce costs, the aluminum foil used in the deep drawing forming laminate is used. If the thickness is reduced to a thickness of about 30 μm to 50 μm, there is a problem in that cracks that cause quality problems occur in the aluminum foil during deep drawing.

  As an invention in which cracking of the aluminum foil does not occur at the time of deep drawing even if the thickness of the aluminum foil used for the deep drawing laminate is reduced to a thickness of about 30 μm to 50 μm, for example, an inorganic material such as calcium carbonate An invention has been proposed in which a plastic sheet of 150 μm to 300 μm mixed with a filler is used as a heat seal layer, an aluminum foil of 40 μm to 50 μm as a barrier layer, and a balanced polypropylene film as a base material layer (see Patent Document 1). .

  Further, the base layer of the deep drawing laminate must be determined according to the required specifications of the deep drawing molded container. When using a biaxially stretched polypropylene film as the base layer of a deep drawing laminate and a general heat sheet film as a heat seal layer as the required specifications for deep drawing containers, quality during deep drawing In particular, cracks that cause problems occur in the aluminum foil used for the barrier layer, making it difficult to manufacture deep-drawn containers. Therefore, when a biaxially stretched polypropylene film is used for the base layer of the laminate for deep drawing and a film having a general heat sheet property is used for the heat seal layer, an Al—Fe-based aluminum alloy foil is used for the barrier layer. Has been proposed (see Patent Document 2). However, there is still a demand for the development of a deep drawing laminate that does not cause aluminum foil cracking during deep drawing.

Japanese Patent Publication No. 6-002367 JP 2011-51120 A

  This invention is made | formed in view of said technical subject, The objective is to provide the laminated body for deep drawing which was excellent in the moldability at the time of manufacturing a deep drawing molded container. Another object of the present invention is to provide a deep drawing laminate comprising the deep drawing laminate.

  As a result of intensive studies to solve the above problems, the present inventors have formed a base material layer from a specific resin layer, and the tensile breaking elongation of the laminate is within a specific range in the MD direction and the TD direction. It has been found that the above-mentioned problems can be solved by adjusting to. The present invention has been completed based on such findings.

That is, according to one aspect of the present invention,
A deep-drawing laminate comprising a base material layer, a barrier layer, and a heat seal layer in this order,
The base material layer includes a polyester resin layer and a polyamide resin layer,
A laminate for deep drawing is provided in which the tensile elongation at break of the laminate is 30% or more in the MD direction and 30% or more in the TD direction.

  In the aspect of the present invention, it is preferable that the tensile breaking elongation of the laminate is 40 to 200% in the MD direction and 40 to 200% in the TD direction.

  In the aspect of the present invention, it is preferable that the ratio of the tensile rupture elongation in the MD direction and the tensile rupture elongation in the TD direction of the laminate is 0.9: 1 to 1.1: 1.

  In the aspect of the present invention, it is preferable that the barrier layer comprises an Al—Fe-based aluminum alloy foil.

  In the aspect of this invention, it is preferable that content of Fe in the said Al-Fe-type aluminum alloy foil is 0.7-1.7%.

  In the aspect of this invention, it is preferable that the said heat seal layer contains polyolefin resin.

  In the aspect of the present invention, it is preferable that an adhesive layer is further included between the base material layer and the heat seal layer.

  Moreover, according to the other aspect of this invention, the deep drawing molded container which consists of said laminated body for deep drawing is provided.

  The laminate for deep drawing according to the present invention is excellent in moldability when producing a deep drawing molded container, and can prevent the barrier layer from cracking during deep drawing. The deep-drawn container according to the present invention is excellent in barrier properties and heat resistance.

It is the schematic sectional drawing which showed one Embodiment of the laminated body for deep drawing by this invention. It is a figure which shows an example of the metal mold | die for deep drawing used for manufacture of the deep drawing molded container by this invention.

<Laminated body for deep drawing>
The deep drawing molded laminate according to the present invention comprises a specific base material layer, a barrier layer, and a heat seal layer in this order. The deep drawing molded laminate may further include an adhesive layer between the base material layer and the heat seal layer, or may further include another resin layer. The tensile strength at break of the laminate for deep drawing at 22 ° C. is 30% or more in the MD direction, preferably 40 to 200%, more preferably 45 to 100%, and still more preferably. 50 to 80%, 30% or more in the TD direction, preferably 40 to 200%, more preferably 45 to 100%, and further preferably 50 to 80%. Such a laminate for deep drawing is excellent in moldability when producing a deep drawing container, and can prevent the barrier layer from cracking during molding.

  The ratio of the tensile breaking elongation in the MD direction to the tensile breaking elongation in the TD direction of the laminate for deep drawing is preferably 0.9: 1 to 1.1: 1, more preferably 0.95: 1. ~ 1.05: 1. If the ratio of the tensile rupture elongation in the MD direction and the tensile rupture elongation in the TD direction of the laminate for deep drawing is about the above range, the laminate extends equally in the MD direction and the TD direction during deep drawing, It is possible to prevent the barrier layer from cracking.

  The tensile elongation at break in the present invention is a value measured at 22 ° C. using a Tensilon universal tester using a test piece according to JIS-Z1702, with a chuck distance of 80 mm and a test speed of 300 m / min. .

  Embodiments of a deep drawing laminate according to the present invention will be described with reference to schematic cross-sectional views. A deep-drawn laminate 11 shown in FIG. 1 includes a base material layer 14, a barrier layer 13, and a heat seal layer 12 in this order. Hereinafter, each layer constituting the deep drawing laminate will be described in detail.

(Base material layer)
The base material layer of the laminate for deep drawing according to the present invention includes a polyester resin layer and a polyamide resin layer. The base material layer preferably has a polyester resin layer on the outer layer side and a polyamide resin layer on the inner layer side (barrier layer side). Examples of the polyester resin include polybutylene terephthalate resin and polyethylene naphthalate resin, and polyethylene terephthalate (PET) resin is particularly preferable. As the polyamide resin layer, nylons such as nylon 6, nylon 6, 6, and nylon 12 are preferably used.

  Although the formation method of a base material layer is not specifically limited, It is preferable to co-extrude and shape | mold a polyester resin layer and a polyamide resin layer. Usually, the thickness of the base material layer is preferably 5 to 100 μm and more preferably 10 to 50 μm from the viewpoint of moldability and transparency.

(Barrier layer)
The barrier layer of the deep drawing laminate according to the present invention preferably includes a metal foil or a vapor deposition film of an inorganic substance or an inorganic oxide. When the deep drawing laminate has a barrier layer, gas barrier properties that prevent permeation of oxygen gas, water vapor, and the like can be improved. In addition, if necessary, light shielding properties that prevent transmission of visible light, ultraviolet light, and the like can be imparted. The deep drawing laminate may have two or more barrier layers. When two or more barrier layers are provided, each may have the same composition or a different composition. The thickness of the barrier layer is preferably 10 to 50 μm, more preferably 15 to 45 μm, from the viewpoint of moldability during deep drawing and cost reduction.

  As the metal foil, an Al—Fe-based aluminum alloy foil is preferably used. The content of Fe in the Al—Fe-based aluminum alloy foil is preferably 0.7 to 1.7, more preferably 1.3 to 1.7. The Al—Fe-based aluminum alloy foil may contain a metal other than Al and Fe. Since the Al—Fe-based aluminum alloy foil is easier to extend than the pure aluminum foil, the use of the Al—Fe-based aluminum alloy foil for the barrier layer can prevent the barrier layer from cracking during deep drawing.

  A vapor deposition film can be formed by a conventionally known method using a conventionally known inorganic substance or inorganic oxide, and its composition and formation method are not particularly limited. As a method for forming a vapor deposition film, for example, a physical vapor deposition method (Physical Vapor Deposition method, PVD method) such as a vacuum vapor deposition method, a sputtering method, and an ion plating method, or a plasma chemical vapor deposition method, a thermochemical method, or the like. Examples thereof include a chemical vapor deposition method (chemical vapor deposition method, CVD method) such as a vapor phase growth method and a photochemical vapor deposition method.

(Heat seal layer)
It is preferable that the heat seal layer of the laminate for deep drawing according to the present invention contains a polyolefin resin that can be formed using a resin having heat sealability. Examples of the polyolefin resin include low-density polyethylene, linear low-density polyethylene, medium-density polyethylene, high-density polyethylene, non-axially stretched polypropylene, biaxially-stretched polypropylene, and polymethylpentene. Examples thereof include a mixture and a mixture of polypropylene and high density polyethylene.

  The formation method of a heat seal layer is not specifically limited, It can form by a conventionally well-known method. For example, the heat seal layer may be formed by extrusion molding a polyolefin resin or a polyolefin film.

(Adhesive layer)
The adhesive layer of the laminate for deep drawing according to the present invention is an adhesive layer or an adhesive resin layer formed in order to bond any two layers by lamination. As an adhesive for laminating, for example, one or two-component cured or non-cured vinyl type, (meth) acrylic type, polyamide type, polyester type, polyether type, polyurethane type, epoxy type, rubber type, Other adhesives such as solvent type, aqueous type, and emulsion type can be used. Examples of the coating method for the adhesive include a direct gravure roll coating method, a gravure roll coating method, a kiss coating method, a reverse roll coating method, a fountain method, a transfer roll coating method, and other methods. As the coating ^{amount, 0.1g / m 2 ~10g / m} 2 ( dry state) position are ^{preferred, 1g / m 2 ~5g / m} 2 ( dry state) position is more preferred.

  In addition, a resin layer made of a thermoplastic resin layer is used as the adhesive resin layer. Specifically, the material of the adhesive resin layer includes a low density polyethylene resin, a medium density polyethylene resin, a high density polyethylene resin, a linear low density polyethylene resin, and an ethylene-α olefin polymerized using a metallocene catalyst. Copolymer resin, ethylene-polypropylene copolymer resin, ethylene-vinyl acetate copolymer resin, ethylene-acrylic acid copolymer resin, ethylene-ethyl acrylate copolymer resin, ethylene-methacrylic acid copolymer resin, Graft polymerization of unsaturated carboxylic acid, unsaturated carboxylic acid, unsaturated carboxylic acid anhydride, ester monomer to ethylene-methyl methacrylate copolymer resin, ethylene-maleic acid copolymer resin, ionomer resin, polyolefin resin, Or graft copolymerized resin, maleic anhydride to polyolefin resin It can be used sexual resin or the like. These materials can be used alone or in combination.

(Additive)
Various conventionally known additives such as a light stabilizer, an ultraviolet absorber, an antioxidant, a filler, a lubricant and the like may be appropriately added to the resin layer constituting the alkali-resistant packaging material according to the present invention as necessary. it can. Conventionally known light stabilizers and ultraviolet absorbers can be used. For example, phenol-based, phosphorus-based, hindered amine-based light absorbers, benzotriazole-based, benzophenone-based, and salicylic acid ester-based ultraviolet absorbers are used. it can.

<Deep-drawn container>
The deep-drawn container according to the present invention is composed of the deep-drawn laminate according to the present invention, and the base material layer is preferably disposed on the outer side and the heat seal layer is disposed on the contents side. The deep-drawn container can be manufactured by deep-drawing a deep-drawing laminate, but the manufacturing method is not particularly limited. For example, a deep-drawing container having a predetermined shape is manufactured by bringing a deep-drawing-molded laminate into close contact with a deep-drawing mold shown in FIG. can do.

(Use)
The deep-drawn container according to the present invention can accommodate various contents requiring barrier properties, but the contents are not particularly limited. For example, the deep-drawn container can be used as a packaging container for foods, pharmaceuticals, medical instruments and the like.

[Example 1]
<Production of deep drawing laminate>
A hybrid film of PET and nylon (thickness: 25 μm, manufactured by Gunze Co., Ltd., trade name: Heptax HLB) as a base material layer, and an Al—Fe-based aluminum alloy foil (thickness: 40 μm, Fe content: barrier layer) 0.7 to 1.3%, manufactured by Toyo Aluminum Co., Ltd., trade name: 8079) were bonded together using a urethane adhesive (manufactured by Mitsui Chemicals, Inc., trade names: Takelac, Takenate). Next, the barrier layer and a linear low-density polyethylene film (thickness: 50 μm, manufactured by Toyobo Co., Ltd., trade name: Rix L6100) as a heat seal layer are bonded together using a urethane-based adhesive, A laminate for deep drawing was obtained. The layer structure of the deep-drawing laminate of Example 1 was as shown in FIG.

[Example 2]
<Production of deep drawing laminate>
A laminate for deep drawing was obtained in the same manner as in Example 1 except that the thickness of the barrier layer was changed to 30 μm.

[Example 3]
<Production of deep drawing laminate>
A laminate for deep drawing was obtained in the same manner as in Example 1 except that the thickness of the barrier layer was changed to 20 μm.

[Example 4]
<Production of deep drawing laminate>
A hybrid film of PET and nylon (thickness: 25 μm, manufactured by Gunze Co., Ltd., trade name: Heptax HLB) as a base material layer, and an Al—Fe-based aluminum alloy foil (thickness: 20 μm, Fe content: barrier layer) 0.7 to 1.3%, manufactured by Toyo Aluminum Co., Ltd., trade name: 8079) were bonded together using a urethane-based adhesive. Next, the barrier layer and a hybrid film of PET and nylon (thickness: 25 μm, manufactured by Gunze Co., Ltd., trade name: Heptax HLB) were bonded together using a urethane-based adhesive. Subsequently, the hybrid film and a linear low density polyethylene film (thickness: 50 μm, manufactured by Toyobo Co., Ltd., trade name: Rix L6100) as a heat seal layer are bonded together using a urethane-based adhesive. A layered product for deep drawing was obtained.

[Example 5]
<Production of deep drawing laminate>
Example 1 except that an Al—Fe-based aluminum alloy foil (thickness: 40 μm, Fe content: 1.2 to 1.7%, manufactured by Toyo Aluminum Co., Ltd., trade name: 8021) was used as the barrier layer. Similarly, a deep drawing molded laminate was obtained.

[Example 6]
<Production of deep drawing laminate>
A laminate for deep drawing was obtained in the same manner as in Example 5 except that the thickness of the barrier layer was changed to 30 μm.

[Example 7]
<Production of deep drawing laminate>
A laminate for deep drawing was obtained in the same manner as in Example 5 except that the thickness of the barrier layer was changed to 20 μm.

[Comparative Example 1]
<Production of deep drawing laminate>
A laminate for deep drawing was obtained in the same manner as in Example 1 except that a biaxially stretched polypropylene film (thickness: 25 μm, manufactured by Santox Co., Ltd., trade name: MF20) was used as the base material layer.

[Comparative Example 2]
<Production of deep drawing laminate>
A deep-drawn laminate was obtained in the same manner as in Example 2 except that a biaxially stretched polypropylene film (thickness: 25 μm, manufactured by Santox Co., Ltd., trade name: MF20) was used as the base material layer.

[Comparative Example 3]
<Production of deep drawing laminate>
A laminate for deep drawing was obtained in the same manner as in Example 1 except that a nylon film (thickness: 15 μm, manufactured by Kojin Co., Ltd., trade name: Bonil Q) was used as the base material layer.

[Comparative Example 4]
<Production of deep drawing laminate>
A laminate for deep drawing was obtained in the same manner as in Example 2 except that a nylon film (thickness: 15 μm, manufactured by Kojin Co., Ltd., trade name: Bonil Q) was used as the base material layer.

[Comparative Example 5]
<Production of deep drawing laminate>
A deep-drawing laminate was obtained in the same manner as in Example 1 except that pure aluminum foil (thickness: 40 μm, product name: 1N30) was used as the barrier layer.

<Performance evaluation of laminate for deep drawing>
The following evaluation was performed using the laminates for deep drawing formed in Examples 1 to 7 and Comparative Examples 1 to 5.

(Tensile break elongation)
Using the deep-drawing laminates prepared in Examples 1 to 7 and Comparative Examples 1 to 5, test pieces based on JIS-Z1702 were prepared. Using the prepared test piece, the tensile breaking elongation was measured using a Tensilon universal testing machine at a chuck distance of 80 mm and a test speed of 300 m / min. The measurement results are shown in Table 1.

(Deep drawing formability evaluation)
Using the deep drawing molded laminates produced in Examples 1 to 7 and Comparative Examples 1 to 5, a deep drawing molded container was created under the following conditions, and a moldability evaluation during deep drawing was performed. .
Deep drawing molding conditions Deep drawing mold: mold shown in FIG.
Molding conditions: 5.6 MPa, 10 seconds, cooling sensation molding (normal temperature).
-Formability evaluation result (circle): The crack did not generate | occur | produce in the barrier layer at the time of deep drawing.
X: A crack occurred in the barrier layer during deep drawing.

DESCRIPTION OF SYMBOLS 11 Deep-drawing laminated body 12 Heat seal layer 13 Barrier layer 14 Base material layer

Claims (5)

A packaging container for foods, pharmaceuticals, or medical devices, comprising a laminate for deep drawing comprising a base material layer, a barrier layer, and a heat seal layer in this order,
The base material layer includes a polyester resin layer and a polyamide resin layer,
The barrier layer comprises an Al-Fe-based aluminum alloy foil;
Breaking elongation The tensile at 22 ° C. of the laminate is 40 to 200% in the MD direction and 40 to 200% in the TD direction, the packaging container. The packaging container according to claim 1, wherein a ratio of a tensile breaking elongation in the MD direction and a tensile breaking elongation in the TD direction of the laminate is 0.9: 1 to 1.1: 1. The packaging container according to claim 1 or 2 , wherein the content of Fe in the Al-Fe-based aluminum alloy foil is 0.7 to 1.7%. The heat seal layer comprises a polyolefin resin, the packaging container according to any one of claims 1-3. The packaging container according to any one of claims 1 to 4 , further comprising an adhesive layer between the base material layer and the heat seal layer.

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