JP2019155611A - Multilayer rust-preventive film for molding, bottom material for deep-drawn package and deep-drawn package - Google Patents

Abstract

To provide a rust-preventive film having rust-preventive effect, gas barrier property and deep drawing moldability and to provide a deep-drawn package using the rust-preventive film.SOLUTION: A multilayer rust-preventive film for molding is a multilayer film composed of at least three layers of an outermost layer, an intermediate layer and an innermost layer and has characteristics as given below: (1) the film has a base material film as the outermost layer and a gas barrier layer as the intermediate layer in which the gas barrier layer ia any of a polyamide-based resin layer, an ethylene/vinyl acetate copolymer saponified product-based resin layer, a layer including a polyamide-based resin and an ethylene/vinyl acetate copolymer saponified product-based resin, or two or more layers thereof; (2) the film contains a volatile rust-preventive agent in the innermost layer: and (3) the innermost layer has heat sealability.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a rust-proof film for deep drawing, a bottom material for a deep-drawn package, and a deep-drawn package, for example, a multilayer rust-proof film for molding that can be suitably used for metal packaging such as metal parts and metal chains, The present invention relates to a bottom material for a deep drawn package and a deep drawn package.

  Conventionally, when storing and transporting metal machines and parts, rust-proof packaging is performed to prevent the surfaces of the machines and parts from being oxidized and rusting. Examples of the rust-proof packaging include a coating of a rust-preventing oil on a metal, and a rust-preventive agent (vaporizable, water-soluble, vaporizable water-soluble) or rust-proof paper.

  Most of the rust preventive oil is liquid, and the rust preventive treatment is performed by immersing the metal product in the rust preventive oil. Although the rust prevention effect period is relatively short, it is characterized in that it can penetrate into gaps of metal products where it is difficult to carry out a rust prevention treatment to form a rust prevention oil film. On the other hand, after storage and transportation, it is necessary to wash the rust preventive oil before use, which requires labor and cost.

  In recent years, many vaporizable rust preventives have been used. A vaporizable rust preventive agent volatilizes at room temperature and adheres to the surface of a metal product and exhibits a rust preventive effect. However, vaporizing rust preventive is not possible in the method of directly spraying or applying a powder or liquid vaporizable rust preventive to metal products, or in the method using rust preventive paper coated or immersed with the vaporizable rust preventive. The agent volatilizes outside the package and the rust prevention effect is lost.

  Therefore, a rust preventive film is used in which a composition obtained by kneading a vaporizable rust preventive agent in a plastic film such as polyethylene is laminated on a base film (Patent Document 1). Moreover, in addition to the layer containing a vaporizable rust preventive agent, a rust preventive film provided with a barrier layer against water vapor and oxygen that causes rusting agent vaporization gas and rusting has been proposed (Patent Document 2, Patent Document 3).

  However, the rust preventive film of Patent Document 1 has a problem that it has no barrier property against the vaporized gas, oxygen or water vapor of the rust preventive agent. In addition, in order to save the effort of further packaging the metal product after film packaging, it is desired to form a package (deep-drawn package) with the rust-proof film itself. Since the barrier vapor deposition layer is provided, the rust preventive film of Patent Document 3 has a problem that the film has no moldability because an O—Ny film is used as a base material.

Japanese Patent Laid-Open No. 49-1644 JP 2007-44984 A JP 2013-59864 A

  The present invention has been made in view of such circumstances, and the problem to be solved is a rust-preventing film having a rust-preventing effect, a gas barrier property, and a deep drawability, a bottom material using the rust-preventing film, and An object of the present invention is to provide a deep-drawn package including the bottom material.

As a result of intensive studies to solve the above problems, the following means can be achieved.
1st this invention is a multilayer film comprised from the outermost layer, an intermediate | middle layer, and at least 3 layers of innermost layers, Comprising: It is a multilayer multilayer antirust film which has the following characteristics.
(1) It has a base material layer as the outermost layer and a gas barrier layer as the intermediate layer, and the gas barrier layer comprises a polyamide resin layer, an ethylene-vinyl acetate copolymer saponified resin layer, a polyamide resin and ethylene- It is either a layer containing a vinyl acetate copolymer saponified resin or a plurality of these layers.
(2) The innermost layer contains a vaporizable rust inhibitor.
(3) The innermost layer has heat sealability.

The “polyamide resin layer” is a layer containing a polyamide resin as a main component.
The “ethylene-vinyl acetate copolymer saponified resin layer” is a layer containing an ethylene-vinyl acetate copolymer saponified resin as a main component.

  In the first aspect of the present invention, the thickness of the outermost layer is preferably 30% or more and 90% or less of the total thickness of the multilayer anticorrosive film for molding.

  In the first aspect of the present invention, the outermost layer is preferably made of a polyester resin or a polyolefin resin.

  The innermost layer is preferably made of a polyolefin resin.

  2nd this invention is the bottom material for deep-drawing packaging bodies formed with the multilayer antirust film for shaping | molding of 1st this invention.

  The third aspect of the present invention is a deep drawn package using the bottom material for a deep drawn package of the second aspect of the present invention.

  According to the present invention, it is possible to provide a rust preventive film having a rust preventive effect, a gas barrier property, and a deep drawability, a bottom material using the rust preventive film, and a deep drawn package including the bottom material. it can.

It is a schematic diagram which shows the layer structure of the multilayer rust prevention film 100 for shaping | molding made into the bottom material shape. It is a schematic diagram which shows the cross-sectional shape of the deep drawing package 300 which included the content 50. FIG.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings. In addition, this invention is not limited at all by the following embodiment.

  In the present embodiment, the “main component” means that the content of each component is preferably 50% by mass or more, more preferably 80%, based on the total resin component constituting each layer (100% by mass). More than 95% by mass, more preferably 95% by mass or more, particularly preferably 100% by mass.

  In the following embodiments, when expressed as “X to Y” (X and Y are arbitrary numbers), unless otherwise specified, “X or more and Y or less” means “preferably larger than X”. And “preferably smaller than Y”. Further, in the following embodiments, when expressed as “X or more” (X is an arbitrary number), the meaning of “preferably greater than X” is included unless otherwise specified, and “Y or less” (Y Unless otherwise specified, it is intended to include “preferably smaller than Y”.

<Multilayer rust prevention film for molding>
The multilayer anticorrosive film 100 for molding of the present invention includes at least three layers of an outermost layer 10, an intermediate layer 20, and an innermost layer 30. In FIG. 1, the schematic diagram which shows the laminated constitution of the multilayer antirust film 100 for shaping | molding of this invention shape | molded by the bottom material shape is shown.

(Outermost layer 10)
The outermost layer is a layer that becomes the base material of the multilayer anticorrosive film for molding. Examples of the constituent materials include polyester resins, polyolefin resins, styrene resins, polylactic acid resins, polyamide resins, and vinyl chloride resins. Conventionally known resin components such as resins and urethane resins can be used, but in the present invention, polyester resins and polyolefin resins are preferably used, and in particular, from the viewpoint of moldability for deep-drawn packages. It is more preferable to use a polyester resin.

  As the polyester resin, a non-crystalline polyester resin obtained by copolymerization with cyclohexanedimethanol or isophthalic acid, or a polyethylene terephthalate resin obtained by solidifying a crystalline polyester in an amorphous state can be used. Necessary waist is given to the squeezed package. In particular, it is preferable to use an amorphous polyester resin (PETG resin) by copolymerization with cyclohexanedimethanol from the viewpoint of film forming properties and molding processability.

  PETG resin refers to a polyester resin in which 5 mol% or more of 1,4-cyclohexanedimethanol component is contained in 100 mol% of a polyhydric alcohol component. From the viewpoint of increasing the degree of non-crystallinity, it is desirable that 1,4-cyclohexanedimethanol is contained in an amount of 10 mol% or more, preferably 12 mol% or more, more preferably 15 mol% or more. Examples include “SKYPET S2008” and “Easter Copolyester GN001” manufactured by Eastman Chemical Co., Ltd.

As the polyolefin-based resin in the outermost layer, HDPE, polypropylene, or the like can be used from the viewpoint of imparting the necessary waist to the deep-drawn package. For example, as HDPE, MFR is preferably 0.01 to 10 g / 10 min, and the density is preferably 920 to 980 kg / m ³ .

  The thickness ratio of the outermost layer to the total thickness of the multilayer anticorrosive film for molding is preferably 30% or more and 90% or less. By setting the thickness ratio of the outermost layer to the total thickness of the multilayer anticorrosive film for molding to 30% or more, good rigidity and curl resistance of the multilayer anticorrosive film for molding can be obtained. In particular, by setting it to 50% or more, it is possible to impart sufficient strength to enclose a metal product, which is preferable. Moreover, favorable deep drawing moldability can be maintained by setting the thickness ratio of the polyester resin layer to 90% or less with respect to the total thickness of the multilayer anticorrosive film for molding. In particular, the thickness of 85% or less is preferable because the thickness of the intermediate layer and the innermost layer having barrier properties can be secured.

  The thickness of the outermost layer is preferably 20 to 700 μm, more preferably 30 to 600 μm, and still more preferably 40 to 500 μm. By setting the thickness to 20 μm or more, it is possible to give a good waist to the package, and by setting the thickness to 700 μm or less, the handling is easy and the molding time is shortened, which is preferable in terms of cost.

(Intermediate layer 20)
An intermediate | middle layer provides gas barrier property to the multilayer multilayer antirust film for shaping | molding. By providing an intermediate layer with gas barrier properties, the multilayer multilayer rust preventive film prevents vaporization of the vaporized gas of the rust preventive agent when it is made into a deep-drawn package, as well as water vapor and oxygen to the metal product of the contents. Can prevent rusting.

  The intermediate layer is mainly composed of at least one resin selected from the group consisting of a polyamide-based resin (hereinafter also referred to as “PA”) and a saponified ethylene-vinyl acetate copolymer (hereinafter also referred to as “EVOH”). Contained as. The intermediate layer may be, for example, a layer mainly composed of PA, a layer mainly composed of EVOH, or a layer mainly composed of a mixed resin of PA and EVOH. . The intermediate layer may be a single layer or a multilayer in which a plurality of layers are stacked. Examples of the multilayer intermediate layer include a laminate of a first intermediate layer mainly composed of PA and a second intermediate layer mainly composed of EVOH.

  The polyamide-based resin is not particularly limited, but a nylon-based resin (hereinafter also referred to as “Ny”) is preferable from the viewpoint of gas barrier properties and pinhole resistance. Examples of nylon resins include polymers of condensation units such as 6 nylon, 66 nylon, 69 nylon, 6-66 nylon, 12 nylon, 11 nylon, 610 nylon, 612 nylon, 6I-6T nylon, and MXD6 nylon, and , Two or more types of these copolymers, and mixtures thereof. Moreover, these nylon-type resins may be used individually by 1 type, and may use 2 or more types together. Among these, as the nylon resin, MXD6 nylon is preferable from the viewpoint of gas barrier properties, 6 nylon and 6-66 nylon are preferable, and 6-nylon is particularly preferable from the viewpoint of pinhole resistance.

  EVOH is preferably one having an ethylene content of 30 mol% or more and 60 mol% or less from the viewpoint of moldability and gas barrier properties. EVOH having a saponification degree of 95% or more is preferable from the viewpoint of moldability and gas barrier properties.

  When providing an intermediate layer mainly composed of PA, the thickness of the intermediate layer is preferably 2 μm or more, more preferably 3 μm or more, further preferably 5 μm or more, and 30 μm or less. Preferably, it is 25 μm or less, and more preferably 20 μm or less. If the thickness of the intermediate layer is 2 μm or more, good gas barrier properties and pinhole resistance can be obtained, and if it is 25 μm or less, good cut property in a deep drawing packaging machine can be obtained.

  When providing an intermediate layer mainly composed of EVOH, the thickness of the intermediate layer is preferably 1 μm or more, more preferably 2 μm or more, and preferably 30 μm or less, and 20 μm or less. More preferably. If the thickness of the intermediate layer is 1 μm or more, good oxygen gas barrier properties can be obtained, and if it is 30 μm or less, good pinhole resistance can be obtained.

  The intermediate layer preferably has a thickness ratio of 2% or more, more preferably 2.5% or more, and more preferably 3% or more from the viewpoint of oxygen permeability, rigidity, and moldability. More preferably, it is 40% or less, preferably 37.5% or less, and more preferably 35% or less.

(Innermost layer 30)
The innermost layer is a layer having heat sealability. The innermost layer is a layer in which a vaporizable rust inhibitor is kneaded or coated. This layer imparts a rust preventive effect to the multilayer multilayer rust preventive film. The innermost layer may be a single layer, or may include a layer in which a vaporizable rust preventive agent is not blended, or may be a multilayer in which a plurality of layers are laminated.
For example, (1) a vaporizable rust preventive material may be kneaded into the innermost layer composed of a single layer, or (2) a vaporizable rust preventive agent is kneaded inside the layer not containing the vaporizable rust preventive agent. It may be a plurality of layers obtained by laminating layers that are included, or (3) a plurality of layers obtained by further laminating a layer not containing a vaporizable rust preventive agent inside (2).

  In the case of (1), a rust-proof film can be obtained with a simple configuration. In the case of (2), after producing a coextruded film, it can manufacture by laminating a rust preventive film inside, and volatilization of the rust preventive agent in a manufacturing process can be minimized. Moreover, in the case of (3), by having another layer inside the layer containing a rust preventive agent, the rust preventive agent volatilizes at an early stage in the manufacturing process or during storage of the package. There is an effect to prevent. In the form (3), the thickness of another layer not containing the rust inhibitor is preferably 50 μm or less, and more preferably 25 μm or less. By carrying out like this, a rust preventive agent can vaporize to the contents side through this another layer.

  When the innermost layer is composed of a plurality of layers, the whole may be coextruded to form a film, or the outermost layer, the intermediate layer, and a part of the innermost layer may be coextruded to form a vaporizable rust preventive. A layer containing an agent and / or a layer not containing a vaporizable rust inhibitor may be laminated. Further, since the vaporizable rust inhibitor vaporizes at room temperature, it is necessary to form the film at as low a temperature as possible when kneaded into a resin.

  The innermost layer preferably imparts flexibility and heat sealability to the multilayer anticorrosive film for molding, and preferably contains a polyolefin resin that is a heat sealable resin. Examples of the polyolefin resin include an ethylene-vinyl acetate copolymer (hereinafter also referred to as “EVA”) and polyethylene (hereinafter also referred to as “PE”). As the innermost layer, a layer mainly composed of EVA may be used, or a layer mainly composed of PE may be used.

  The ethylene content of EVA is not particularly limited. The ethylene content of EVA is preferably 1.5 mol% or more and 20 mol% or less, preferably 3 mol% or more and 15 mol% or less, from the viewpoint of film formation stability of the multilayer anticorrosive film for molding. Is more preferable.

  There is no limitation in particular as PE. Examples of PE include low density polyethylene (hereinafter also referred to as “LDPE”), linear low density polyethylene (hereinafter also referred to as “LLDPE”) and high density polyethylene (hereinafter also referred to as “HDPE”), and A mixture of these is used.

  The thickness of the innermost layer is preferably 0.5 μm or more, more preferably 1 μm or more, further preferably 1.5 μm or more, from the viewpoint of heat sealability, rigidity, and moldability. It is preferably 100 μm or less, more preferably 90 μm or less, and still more preferably 80 μm or less.

  The thickness of the heat seal layer (the innermost layer lid material and the layer to be heat sealed) has a thickness ratio of 5% or more with respect to the thickness of the outermost layer from the viewpoint of heat sealability, rigidity and moldability. Preferably, it is 6% or more, more preferably 7% or more, more preferably 65% or less, preferably 60% or less, and 58% or less. More preferably.

  As described above, the innermost layer may be a single layer or a laminate of multiple layers. As the multilayer heat seal layer, for example, a polyolefin resin mainly composed of a polyolefin resin And a polyolefin resin layer (hereinafter also referred to as “EP layer”) having an easy peel (hereinafter also referred to as “EP”) function.

  The resin having an easy peel function is not particularly limited, and examples thereof include a mixed resin of two incompatible polyolefin resins. Examples of the mixed resin include a mixed resin of LLDPE and polybutene (hereinafter also referred to as “PB”), a mixed resin of EVA and polypropylene (hereinafter also referred to as “PP”), a mixed resin of PP and LDPE, PP Resin and ionomer (hereinafter also referred to as “IO”), PP and ethylene-acrylic acid copolymer (hereinafter also referred to as “EAA”), and PP and ethylene-methyl methacrylate copolymer (Hereinafter also referred to as “EMMA”) and the like. Among these, the mixed resin is preferably a mixed resin of LLDPE and PB and a mixed resin of PP and LDPE from the viewpoint of an easy peel function.

  The mixed resin preferably contains 35% by mass or more of two incompatible polyolefin-based resins from the viewpoint of obtaining good openability of the deep-drawn package by an easy peel function.

  The thickness of the EP layer is preferably 2 μm or more, more preferably 3 μm or more, further preferably 4 μm or more, more preferably 15 μm or less, and even more preferably 12 μm or less. More preferably, it is 10 μm or less. If the EP layer has a thickness of 2 μm or more, a stable film-forming property of the multilayer anticorrosive film for molding can be obtained. Moreover, if thickness is 15 micrometers or less, it can make it difficult to generate | occur | produce a fuzz and a film | membrane residue at the time of peeling, and a favorable peeling external appearance is obtained.

  Examples of the polyolefin resin used for the layer having a rust prevention effect (a layer in which a rust inhibitor is kneaded or coated) include polyethylene. Among these, LDPE and LLDPE are preferable as resins having a low melting point that can be formed at a low temperature.

  As the rust preventive agent to be blended in the innermost layer, a vaporizable rust preventive agent is preferable, and those for steel, copper and copper alloy may be used alone or in combination.

  As the vaporizable rust preventive agent, there is one selected from one or more kinds of aliphatic or aromatic acid each class ammonium salt. Examples of the vaporizable rust preventive for steel include amine nitrites, amine carboxylates, amine chromates, and carboxylic esters, and mixtures thereof. Examples of vaporizable rust preventives for copper and copper alloys include heterocyclic compounds, thioureas, and those having a mercapto group. Examples of the heterocyclic compound include those having a triazole ring, a pyrrole ring, a pyrazole ring, a thiazole ring, or an imidazole ring.

  Many of these vaporizable rust preventives are harmful to the human body and must be handled with care. Considering the health of workers, it is preferable to use a vaporizable rust preventive mainly composed of a carboxylate. It is also preferred to use amine carboxylates.

  As a compounding quantity of a vaporizable rust preventive agent, 0.1 mass% or more and 10 mass% or less are preferable on the basis of the layer containing this rust preventive agent from a viewpoint of a rust preventive effect, and 0.5 mass% or more and 5 mass% are preferable. % Or less is more preferable. When the content is 0.5% by mass or more, a sufficient effect of the rust inhibitor is obtained, and when the content is 5% by mass or less, the film is preferable in terms of appearance and cost.

(Other additives, other layers)
In each layer of the multilayer anticorrosive film for molding of the present invention, additives such as an ultraviolet absorber, a light stabilizer, an antioxidant, a plasticizer, a nucleating agent and a lubricant are added as long as the effects of the present embodiment are not impaired. You may mix.

  The multilayer anticorrosive film for molding of the present invention has a thickness of 30 μm or less, preferably 25 μm, between the outermost layer and the intermediate layer and / or the interlayer between the intermediate layer and the innermost layer within the range where the effects of the present invention are exhibited. The following adhesive layers, adhesive resin layers and recycled resin layers, polyester resin layers or polyolefin resin layers that impart heat resistance, and the like may be laminated.

  The adhesive resin is not particularly limited as long as various resin layers constituting each layer can be bonded with a required strength. The adhesive resin is preferably a polyolefin resin modified with an unsaturated carboxylic acid or a derivative thereof. Examples of the unsaturated carboxylic acid include acrylic acid, methacrylic acid, maleic acid, fumaric acid, crotonic acid, itaconic acid, and citraconic acid.

  As the adhesive resin, esters of unsaturated carboxylic acids and anhydrides may also be used. In addition, as an adhesive resin, derivatives of methyl acrylate, methyl methacrylate, ethyl acrylate, propyl acrylate, butyl acrylate, butyl methacrylate, vinyl acetate, glycidyl acrylate, glycidyl methacrylate, acrylamide, methacrylamide and sodium acrylate Etc. may be used.

  Specifically, as the adhesive resin, for example, a commercial product such as trade name: Admer (manufactured by Mitsui Chemicals) can be suitably used. Among these, as the adhesive resin, when a PP layer, a PE layer, an EVOH layer, and a polyester resin layer are bonded, a special polyolefin-based adhesive resin and a polyethylene elastomer-based adhesive resin are useful. Further, as the adhesive resin, when the EVOH layer, the PP layer and the PE layer are bonded, an LLDPE type or a PP type can be preferably used, and a PP type is particularly preferable.

<Manufacturing method of multilayer antirust film for molding>
The molding multilayer rust preventive film of the present invention can be produced using a conventionally known method. The multilayer anticorrosive film for molding can be produced by, for example, an extrusion lamination method, a coextrusion inflation method, a coextrusion T-die method, or the like. Among these, it is preferable to use a coextrusion T-die method as a method for producing a multilayer anticorrosive film for molding.

  When the innermost layer is composed of a plurality of layers, the entire multilayer anticorrosive film for molding may be coextruded to form a film, or the outermost layer, the intermediate layer, a part of the innermost layer (the intermediate layer side) The other part of the innermost layer may be heat-laminated or dry-laminated. For example, as another part of the innermost layer, a film containing a vaporizable rust inhibitor may be thermally laminated on the inner layer side of the coextruded film to form a multilayer rust preventive film for molding. A heat-sealing film that does not contain a vaporizable rust preventive agent may be heat laminated on the inner layer side to form a multilayer rust preventive film for molding.

<Deep-drawn package 300, bottom material 150>
The multilayer anticorrosive film for molding according to the above embodiment can be used for a deep drawn package by molding. FIG. 2 is a schematic cross-sectional view of deep-drawn package 300 according to the embodiment of the present invention. As shown in FIG. 2, the deep-drawn package 300 includes a bottom material 150 obtained by deep-drawing the multilayer anticorrosive film for molding 100 according to the above-described embodiment, and a lid 200 provided so as to cover the bottom material. Is provided. The bottom material 150 is provided with a bottom portion having a predetermined depth at the center by deep drawing. Contents 50 such as metal parts are accommodated in the bottom. Further, the bottom material 150 is provided with the multilayer anticorrosive film 100 so that the outer side of the bottom part becomes the outermost layer 10 and the inner side becomes the innermost layer 30. As for the bottom material 150, the innermost layer 30 of an outer edge part (seal part) is adhere | attached on the cover material 200 by heat sealing. Thus, the deep drawing package 300 which has a rust prevention effect can be obtained by using the multilayer antirust film 100 for shaping | molding as the bottom material 150 of a deep drawing package.

  The lid member 200 is not particularly limited as long as it can be heat sealed to the bottom member. Examples of the lid material include, for example, a dry laminated laminate of a stretched polypropylene resin film (hereinafter also referred to as “OPP”), a transparent vapor-deposited polyethylene terephthalate film and an LLDPE film, and a stretched polyethylene terephthalate (hereinafter also referred to as “OPET”) film. And a laminate obtained by dry-laminating a coextruded film including an EVOH layer or an Ny layer and using LLDPE as a seal layer, or a film obtained by dry-laminating an LLDPE film as a seal layer on a stretched nylon film.

  Hereinafter, the present invention will be described in more detail based on examples made to clarify the effects of the present invention. In addition, this invention is not limited at all by the following examples and comparative examples.

<Example 1>
A multilayer film having the following layer structure was produced by coextrusion molding.
PETG (400 μm) / Adhesive resin (20 μm) / Ny (15 μm) / Adhesive resin (12 μm) / LDPE (15 μm)
PETG: 30 mol% copolymer of 1,4-cyclohexanedimethanol Adhesive resin: “Admer” manufactured by Mitsui Chemicals
Ny: Nylon 6 Lid: A film obtained by dry laminating a biaxially stretched nylon 6 film (15 μm thickness) and a linear low density polyethylene film (50 μm thickness) with a two-component curable urethane adhesive,
Rust prevention film (30 μm): a film in which LDPE having heat sealability and a rust prevention agent (amine carboxylates, 1% by mass) are blended,
The antirust film (30 μm) was bonded to the LDPE layer side of the multi-layer film having the above-described structure by heat lamination to obtain a multi-layer anti-rust film for molding. The rust-proof film was deep-drawn into the shape shown in FIG. An iron plate was put inside, covered with a cover material, and sealed by heat sealing to form a package.

<Example 2>
Except having used the following structure as a multilayer film, it carried out similarly to Example 1, and obtained the multilayer antirust film for shaping | molding, a bottom material, and a package.
PETG (52 μm) / Adhesive resin (20 μm) / EVOH (15 μm) / Adhesive resin (12 μm) / LDPE (15 μm)
PETG: 30 mol% copolymer of 1,4-cyclohexanedimethanol Adhesive resin: “Admer” manufactured by Mitsui Chemicals
EVOH: ethylene content 32 mol%

<Example 3>
A multilayer film having the following layer structure was produced by coextrusion molding.
HDPE (52 μm) / Adhesive resin (20 μm) / Ny (15 μm) / Adhesive resin (12 μm) / LDPE (10 μm)
HDPE: MFR 7.0 g / 10 min, density 963 kg / m ³
Adhesive resin: “Admer” manufactured by Mitsui Chemicals, Inc.
Ny: 6-nylon Anticorrosion film (30 μm): film in which LDPE and an antirust agent (non-amine carboxylate, 1% by mass) are blended,
A film in which a rust-proof film (30 μm) was bonded to the LDPE layer side of the constituent film by dry lamination was produced. Furthermore, a LDPE (10 μm) film having heat sealability was bonded to the rust-proof film side by heat lamination to obtain a multilayer rust-proof film for molding. Thereafter, in the same manner as in Example 1, a bottom material and a package were produced.

<Comparative Example 1>
A multilayer film having the same configuration as in Example 1 was produced, and the rust preventive film was not hot laminated, and this was directly deep-drawn to obtain a bottom material. Thereafter, a package was produced in the same manner as in Example 1.

<Comparative example 2>
A rust-proof film (30 μm) used in Example 1 and a lid material were combined and bag-formed by heat sealing, and an iron plate was put in the bag to prepare a sample.

<Comparative Example 3>
A film composed of a single polyethylene-based resin and a lid were combined and formed into a bag by heat sealing, and an iron plate was placed in the bag to prepare a sample.

The following evaluation was performed about the obtained sample and the used film.
The sample configuration and evaluation results are shown in Table 1.

(1) Rust prevention evaluation Each sample was stored in an environment of 50 ° C and 95% RH for 1 week, 4 weeks, and 6 weeks, and the degree of rust generation was evaluated.
○: Rust is not generated.
Δ: There is thin rust.
X: Rust is generated.

(2) Gas barrier property About the gas barrier property, about each sample after storing for 6 weeks in 50 degreeC95% RH environment, it evaluated by the value of the oxygen concentration inside a package. When sealing the package, the inside is replaced with nitrogen so that the oxygen concentration is 0.1% or less.
○: Oxygen concentration kept below 20% (less than normal air concentration).
X: Oxygen concentration is 20% or more (normal air concentration).

(3) Deep-drawing formability The film produced in each example was 80 mm in length, 80 mm in width, and 30 mm in depth on a deep-drawing packaging machine under conditions of a forming temperature of 90 ° C., a forming heating time of 2 seconds, and a forming air pressure time of 3 seconds. The shape was molded into a bottom material (length 90 mm × width 90 mm), an iron plate was placed as the contents, a heat-sealable film was used as a lid, a deep-drawn package was produced, and evaluated according to the following criteria.
○: There is no molding unevenness, and the visibility of the contents is good.
Δ: Although there is molding unevenness, the visibility of the contents is good.
X: There is molding unevenness and the visibility of the contents is poor.

(4) Comprehensive evaluation Comprehensive evaluation was performed about the effect and feasibility of this invention on the following references | standards based on the evaluation item of said (1)-(3).
○: Only ○ or those having Δ.
X: One having one or more xs.

  By using a deep-drawn molded product using the multilayer anticorrosive film for molding of the present invention, it becomes possible to package metal products that do not require rust-preventing oil.

Claims (6)

A multilayer rust preventive film for molding, which is a multilayer film composed of at least three layers of an outermost layer, an intermediate layer, and an innermost layer, and has the following characteristics.
(1) It has a base material layer as the outermost layer and a gas barrier layer as the intermediate layer. It is either a layer containing a vinyl acetate copolymer saponified resin or a plurality of these layers.
(2) The innermost layer contains a vaporizable rust inhibitor.
(3) The innermost layer has heat sealability.   The multilayer antirust film for molding according to claim 1, wherein the thickness of the outermost layer is 30% or more and 90% or less of the total thickness of the multilayer antirust film for molding.   The multilayer outer rust preventive film for molding according to claim 1 or 2, wherein the outermost layer is made of a polyester resin or a polyolefin resin.   The multilayer inner rust preventive film for molding according to any one of claims 1 to 3, wherein the innermost layer is made of a polyolefin-based resin.   The bottom material for deep-drawing packaging bodies formed by the multilayer anticorrosive film for molding according to any one of claims 1 to 4.   A deep drawn package using the bottom material for a deep drawn package according to claim 5.

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