JP2021138066A - Laminated film and film laminate using the same - Google Patents

Abstract

To provide a laminated film having an inorganic layer on at least one surface of a base film, which can prevent deterioration of gas barrier property even when a film having poor heat resistance is used as the base film.SOLUTION: Provided is a laminated film having a constitution where an anchor layer and an inorganic layer are laminated in this order on at least one surface of a base film (1). The anchor layer has a storage modulus (E') at 120°C of 10 MPa or more and has a thickness of 0.02 to 5.00 μm.SELECTED DRAWING: None

Description

The present invention relates to a laminated film having excellent gas barrier properties and a film laminated body using the same.

Conventionally, a gas barrier laminated film having a structure in which a plastic film is used as a base material and a layer (referred to as "inorganic material layer") mainly made of an inorganic substance such as an inorganic oxide vapor deposition layer is formed on the surface of the base material is water vapor. It is widely used for packaging articles that require blocking of various gases such as oxygen and oxygen, for example, packaging for preventing deterioration of foods, industrial products, pharmaceuticals, and the like.
In addition to packaging applications, new applications such as liquid crystal display elements, solar cells, electromagnetic wave shields, touch panels, EL substrates, and color filters have also been attracting attention in recent years for this gas barrier laminated film.

Various improvements have been studied for the gas barrier laminated film having such an inorganic material layer.
For example, from the viewpoint of providing transparency and gas barrier properties, as well as boil resistance and retort resistance that do not cause deposition, etc., a functional group-containing silane coupling agent or silane coupling agent is applied to at least one surface of the plastic base material. A vapor-deposited film is disclosed in which a primer layer composed of a composite of a hydrolyzate, a polyol and an isocyanate compound, and an inorganic oxide thin film layer having a thickness of 5 to 300 nm are sequentially laminated (Patent Document 1).

Further, from the viewpoint of excellent gas barrier properties and adhesion strength between the constituent layers, it is composed of a base film / inorganic thin film layer / anchor layer / inorganic thin film layer, and the thickness of the anchor layer is 0.1 to 10 nm. The film is disclosed (Patent Document 2).

Further, in a barrier film formed by laminating a silicon oxide film (SiOx) as a barrier layer on one side or both sides of a plastic base material, the barrier layer is composed of at least two or more silicon oxide films, and the silicon oxide is formed. The film thickness per film layer is 10 nm or more and 50 nm or less, the film thickness of the barrier layer composed of the two or more silicon oxide films is 20 nm or more and 200 nm or less, and the ratio of carbon atoms in the barrier layer. Is 10 at. % Or less, a gas barrier laminated film is disclosed (Patent Document 3).

On the other hand, various proposals have been made to enhance the gas barrier property of the polylactic acid film, which is a biodegradable film.
For example, it is disclosed that by adjusting the ratio of crystalline and amorphous regions of a polylactic acid film, both adhesion and gas barrier properties can be achieved (Patent Document 4).

Further, it is disclosed that both gas barrier property and transparency are achieved by setting the plane orientation of the polylactic acid film and the amount of heat of crystal melting within a specific range (Patent Document 5).

Further, a gas barrier film having good interlayer adhesion is disclosed by providing an anchor layer containing a silane coupling agent on the polylactic acid film (Patent Document 6).

Japanese Unexamined Patent Publication No. 2000-238172 International Publication No. 2007-034773 Pamphlet JP-A-2009-101548 Japanese Patent No. 4452574 Japanese Unexamined Patent Publication No. 2006-69218 Japanese Unexamined Patent Publication No. 2013-233658

As described above, various studies have been made on the gas barrier laminated film having an inorganic layer in order to enhance the gas barrier property. However, it was found that the gas barrier property may deteriorate when heat is applied during the manufacturing process or use. In particular, when a film having inferior heat resistance such as a polylactic acid film or a polyolefin film is used as a base film, this tendency is strong, and the problem that the gas barrier property is lowered when heat is applied has been remarkable.

An object of the present invention is a laminated film having an inorganic layer on at least one side of the base film, and a gas barrier even when a film having inferior heat resistance such as a polylactic acid film or a polyolefin film is used as the base film. It is an object of the present invention to provide a new laminated film capable of preventing deterioration of properties and a film laminate using the new laminated film.

The present invention is a laminated film having a structure in which an anchor layer and an inorganic layer are laminated in this order on at least one side of the base film (1), and the storage elastic modulus (E') of the anchor layer at 120 ° C. ) Is 10 MPa or more, and the thickness of the anchor layer is 0.02 to 5.00 μm.

The present invention also proposes a film laminate having a structure in which a base film (2) is bonded to the outermost surface of the laminated film via an adhesive layer.

In the laminated film proposed by the present invention, by providing a specific anchor layer on the base film, even when a base film having poor heat resistance is used, the base film is deformed during heat treatment. Can be relaxed by. Therefore, it is possible to prevent the generation of cracks in the inorganic layer during the heat treatment, and it is possible to obtain the desired gas barrier property. Therefore, the laminated film proposed by the present invention and the film laminate using the same are used for packaging articles that require blocking of various gases such as water vapor and oxygen, for example, preventing deterioration of foods, industrial products, pharmaceuticals, and the like. It can be widely used as a packaging material for products. In addition to packaging applications, it can be suitably used for various members such as liquid crystal display elements, solar cells, electromagnetic wave shields, touch panels, EL substrates, and color filters.

Next, the present invention will be described based on examples of embodiments. However, the present invention is not limited to the embodiments described below.

<< This laminated film >>
In the laminated film (referred to as "the present laminated film") according to an example of the embodiment of the present invention, an anchor layer and an inorganic material layer are laminated in this order on at least one side of the base film (referred to as the "main base film"). It is a laminated film having such a structure.

<This base film>
The material and composition of the base film constituting the laminated film are not limited as long as they are transparent and have the necessary and sufficient rigidity.

The base film may have a single-layer structure or a multi-layer structure.
When the base film has a multi-layer structure, it may have a two-layer or three-layer structure, or may have a four-layer or more multi-layer structure.

The poorer the heat resistance of the base film, the more the effect of the present invention can be enjoyed. From this point of view, the base film is preferably, for example, a polylactic acid film or a polyolefin film. However, it is not limited to these.

In the present invention, the "polylactic acid film" or "polyolefin film" refers to a layer containing a polylactic acid resin or a polyolefin resin as a main component resin regardless of whether the film has a single-layer structure or a multilayer structure. Means a provided film. Preferably, the film is mainly composed of a polylactic acid resin or a polyolefin resin as a main component resin.
Among them, regardless of whether the base film has a single-layer structure or a multi-layer structure, it is preferable that the main component resin of each layer is a polylactic acid resin or a polyolefin resin.

At this time, the "main layer" means the layer in the case of a single-layer film, and in the case of a multilayer film, the layer having the largest thickness ratio among the layers constituting the film.
Further, the "main component resin" means the resin having the highest content ratio among the resins constituting each layer, for example, 50% by mass or more, particularly 70% by mass or more, particularly 80% by mass among the resins constituting each layer. It is a resin that occupies the above (including 100% by mass).

The above-mentioned polylactic acid film or polyolefin film may contain a resin other than the polylactic acid resin or the polyolefin resin or a component other than the resin as long as it has a layer containing the polylactic acid resin or the polyolefin resin as the main component resin. ..

(Polylactic acid resin)
The above-mentioned polylactic acid resin is a homopolymer of D-lactic acid or L-lactic acid, or a copolymer thereof. That is, the above-mentioned polylactic acid resin includes poly (D-lactic acid) whose structural unit is D-lactic acid, poly (L-lactic acid) whose structural unit is L-lactic acid, and both L-lactic acid and D-lactic acid. Any of poly (DL-lactic acid) which is a polymer, or a mixed resin thereof may be used. Further, it may be a mixed resin of a plurality of the above copolymers having different copolymerization ratios of D-lactic acid and L-lactic acid.

In the above-mentioned copolymer of L-lactic acid and D-lactic acid, the copolymerization ratio of D-lactic acid and L-lactic acid (hereinafter abbreviated as "D / L ratio") is preferably "3/97" to "3/97". It is "15/85" or "85/15" to "97/3", more preferably "5/95" to "15/85" or "85/15" to "95/5", and further. It is preferably "8/92" to "15/85" or "85/15" to "92/8", and particularly preferably "10/90" to "15/85" or "85/15" to "85/15" to " 90/10 ".

It is also possible to blend polylactic acid resins having different D / L ratios, and blending is more preferable because the D / L ratio of the polylactic acid resin can be adjusted more easily. In this case, the average value of the D / L ratios of the plurality of lactic acid-based polymers may be within the above range. By blending two or more types of polylactic acid resins having different D / L ratios and adjusting the crystallinity according to the intended use, it is possible to achieve a balance between heat resistance and heat shrinkage characteristics.

The polylactic acid resin may be copolymerized with a small amount of copolymerization component as long as the essential properties of the PLA resin are not impaired.
Examples of the copolymerization component include α-hydroxycarboxylic acids other than lactic acid, non-aliphatic dicarboxylic acids such as terephthalic acid, aliphatic dicarboxylic acids such as succinic acid, and non-aliphatic diols such as ethylene oxide adduct of bisphenol A. , At least one selected from the group consisting of aliphatic diols such as ethylene glycol can be mentioned.

Examples of α-hydroxycarboxylic acid units other than lactic acid include glycolic acid, 3-hydroxybutyric acid, 4-hydroxybutyric acid, 2-hydroxy-n-butyric acid, 2-hydroxy-3,3-dimethylbutyric acid, and 2-hydroxy-3. Examples thereof include bifunctional aliphatic hydroxycarboxylic acids such as -methylbutyric acid, 2-methyllactic acid and 2-hydroxycaproic acid, and lactones such as caprolactone, butyrolactone and valerolactone.

Examples of the diol unit include ethylene glycol, 1,4-butanediol, 1,4-cyclohexanedimethanol and the like. Examples of the dicarboxylic acid unit include succinic acid, adipic acid, suberic acid, sebacic acid, dodecanedic acid and the like.

The copolymerization ratio of lactic acid and a copolymer of α-hydroxycarboxylic acid other than lactic acid is not particularly limited. Above all, the higher the proportion of lactic acid, the less the consumption of petroleum resources, which is preferable, and it is preferable to copolymerize at a proportion that does not exceed the range of the Vicat softening point described later.
Specifically, the copolymerization ratio of the copolymer of lactic acid and α-hydroxycarboxylic acid other than lactic acid, aliphatic diol, or aliphatic dicarboxylic acid is lactic acid / α-hydroxycarboxylic acid other than lactic acid, aliphatic. The diol or aliphatic dicarboxylic acid = "95/5" to "10/90", preferably "90/10" to "20/80", and more preferably "80/20" to "30/70". ..
When the copolymerization ratio is within the above range, a film having a good balance of physical properties such as rigidity, transparency and impact resistance can be obtained. In addition, examples of the structures of these copolymers include random copolymers, block copolymers, and graft copolymers, and any structure may be used. However, from the viewpoint of impact resistance and transparency of the film, block copolymers or graft copolymers are preferable.

The polylactic acid resin can also contain a small amount of a chain extender, for example, a diisocyanate compound, an epoxy compound, an acid anhydride, or the like for the purpose of increasing the molecular weight.

The mass average molecular weight of the polylactic acid resin is 20,000 or more, preferably 40,000 or more, more preferably 60,000 or more, and the upper limit is 400,000 or less, preferably 350,000 or less, further preferably 300, It is 000 or less. When the mass average molecular weight of the polylactic acid resin is 20,000 or more, an appropriate resin cohesive force can be obtained, the strength and elongation of the film is insufficient, or embrittlement can be suppressed. On the other hand, when the mass average molecular weight is 400,000 or less, the melt viscosity can be lowered, which is preferable from the viewpoint of improving production and productivity.

As the polymerization method of the polylactic acid resin, a known method such as a condensation polymerization method or a ring-opening polymerization method can be adopted. For example, in the case of the condensation polymerization method, D-lactic acid, L-lactic acid, or a mixture thereof can be directly dehydrated and condensed to obtain a polylactic acid resin having an arbitrary composition. Further, in the ring-opening polymerization method, a poly having an arbitrary composition is obtained by ring-opening polymerization of lactide, which is a cyclic dimer of lactic acid, in the presence of a predetermined catalyst while using a polymerization modifier or the like as necessary. Lactide resin can be obtained. The lactide includes DL-lactide, which is a dimer of L-lactic acid, and by mixing and polymerizing these as necessary, a polylactic acid resin having an arbitrary composition and crystallinity can be obtained. ..

As a typical example of the polylactic acid resin, "Nature Works" manufactured by Nature Works LLC is commercially available. Further, as a specific example of the random copolymer of PLA resin, diol and dicarboxylic acid, for example, "GS-Pla" (manufactured by Mitsubishi Chemical Co., Ltd.) can be mentioned, and as a specific example of the block copolymer, for example, " "Pramate" (manufactured by DIC) can be mentioned.

(Polyolefin resin)
Examples of the above-mentioned polyolefin resin include ethylene-based copolymers such as polyethylene resin, polypropylene resin, ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, and ethylene-methyl acrylate copolymer. .. Above all, from the viewpoint of heat shrinkage and moldability, it is preferable to use a polyethylene resin, a polypropylene resin, or a mixture thereof.

Examples of the polyethylene resin include medium density polyethylene resin (MDPE) having a density of 0.92 ^{g / cm 3} or more and 0.94 g / cm ³ or less, low density polyethylene resin (LDPE) having a density of less than ^{0.92 g / cm 3, and linear polyethylene resin.} Chain low density polyethylene resin (LLDPE) can be mentioned. Among these, linear low density polyethylene resin (LLDPE) is preferably used from the viewpoints of stretchability, impact resistance of the film, transparency and the like.

Examples of the linear low-density polyethylene resin (LLDPE) include a copolymer of ethylene and an α-olefin having 3 or more and 20 or less carbon atoms, preferably 4 or more and 12 or less carbon atoms. Examples of α-olefins include propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, 3-methyl-1-butene and 4-. Methyl-1-pentene and the like are exemplified. Of these, 1-butene, 1-hexene, and 1-octene are preferably used. Further, only one type of α-olefin to be copolymerized may be used alone, or two or more types may be combined.

The polyolefin resin contains a polyethylene component, and the content thereof is preferably 70% by mass or more, more preferably 75% by mass or more. If it is 70% by mass or more, the strength of the entire film can be maintained.

In particular, it is preferable that the density of the polyethylene resin is 0.910 g / cm ³ or less, more preferably 0.905 g / cm ³ or less, more preferably 0.900 g / cm ³ or less. The lower limit is particularly preferably but 0.800 g / cm ³ or more are not limited to, more preferably 0.850 g / cm ³ or more, more preferably 0.880 g / cm ³ or more. When the density is 0.910 g / cm ³ or less, the affinity with polylactic acid is improved, the stretchability is maintained, and the heat shrinkage rate in the practical temperature range (70 ° C. or higher and 90 ° C. or lower) can be sufficiently obtained. can. On the other hand, when the density is 0.800 g / cm ³ or more, the waist (rigidity at room temperature) and heat resistance of the entire film are not significantly reduced, which is preferable in practice.

As the polyethylene resin, one having a melt flow rate (MFR: JIS K 7210, temperature: 190 ° C., load: 21.18N) of 0.1 g / 10 minutes or more and 10 g / 10 minutes or less is preferably used. When the MFR is 0.1 g / 10 minutes or more, the extrusion processability can be maintained well, while when the MFR is 10 g / 10 minutes or less, the thickness unevenness of the laminated film and the decrease in mechanical strength are less likely to occur, which is preferable.

Examples of the polypropylene resin include a homopropylene resin and a soft polypropylene resin having flexibility as compared with the homopropylene resin. Examples of the soft polypropylene resin include random polypropylene resin, block polypropylene resin, and propylene-ethylene rubber. Among these, a random polypropylene resin is particularly preferably used from the viewpoint of stretchability and fracture resistance.

In the random polypropylene resin, examples of the α-olefin copolymerized with propylene include those having 2 to 20 carbon atoms, more preferably 4 to 12 carbon atoms, and ethylene, 1-butene, and 1-pentene. , 1-Hexene, 1-Heptene, 1-octene, 1-nonene, 1-decene and the like can be exemplified.
Among them, from the viewpoints of stretchability, heat shrinkage characteristics, impact resistance and transparency of the film, rigidity, etc., the content of propylene unit as α-olefin is 80% by mass or more, preferably 85% by mass or more, more preferably 90. Random polypropylene of mass% or more is particularly preferably used. Further, only one type of α-olefin to be copolymerized may be used alone, or two or more types may be combined.

The melt flow rate (MFR) of polypropylene resin is usually 0.5 g / 10 minutes or more, preferably 1.0 g / 10 minutes or more in MFR (JIS K 7210, temperature: 230 ° C., load: 21.18 N). And it is desirable that it is 15 g / 10 minutes or less, preferably 10 g / 10 minutes or less.

As specific examples of commercially available products, as polyethylene resin, the trade names "Novatec LD, LL", "Kernel", "Toughmer A, P" (manufactured by Nippon Polyech), "Suntech HD, LD" (manufactured by Asahi Kasei Chemicals), "HIZEX" "ULTZEX" "EVOLUE" (manufactured by Mitsui Chemicals), "More Tech" (manufactured by Idemitsu Kosan), "UBE Polyethylene" "UMERIT" (manufactured by Ube Industries), "NUC Polyethylene" "Nackflex" (manufactured by Nippon Unicar) ), "Engage" (manufactured by Dow Chemicals, Inc.) and the like.

As polypropylene resin, trade names "Novatec PP", "WINTEC", "Toughmer XR" (manufactured by Japan Polypropylene Corporation), "Mitsui Polypro" (manufactured by Mitsui Chemicals), "Sumitomo Noblen", "Tough Serene", "Excellen EPX" (manufactured by Sumitomo Chemical Co., Ltd.) ), "IDEMITSU PP", "IDEMITSU TPO" (manufactured by Idemitsu Kosan Co., Ltd.), "Adflex" "Adsil" (manufactured by Sun Aroma Co., Ltd.), "VERSIFY" (manufactured by Dow Chemicals Co., Ltd.) and the like.

As the polyolefin resin, a copolymer of ethylene and a copolymerizable monomer can also be preferably used. Examples of copolymers of ethylene and copolymerizable monomers include ethylene-vinyl acetate copolymers, ethylene-ethyl acrylate copolymers, and ethylene-methyl acrylate copolymers.

The ethylene content of the ethylene-vinyl acetate copolymer, the ethylene-ethyl acrylate copolymer, and the ethylene-methyl acrylate copolymer is 70% by mass or more, preferably 75% by mass or more, and 95% by mass or less, preferably 95% by mass or less. It is preferably 90% by mass or less, more preferably 85% by mass or less. When the ethylene content is 70% by mass or more, the fracture resistance and shrinkage characteristics of the entire film can be maintained satisfactorily.

Commercially available ethylene-vinyl acetate copolymers (EVA) include, for example, "Evaflex" (manufactured by Mitsui DuPont Polychemical), "Novatec EVA" (manufactured by Mitsubishi Chemical Corporation), and "Evaslen" (manufactured by DIC Corporation). , "Evertate" (manufactured by Sumitomo Chemical Corporation) can be mentioned. As a commercially available ethylene / ethyl acrylate copolymer (EEA), for example, "Evaflex EEA" (manufactured by Mitsui DuPont Polychemical Co., Ltd.), and as an ethylene / methyl acrylate copolymer, "Elvaloi AC" (Mitsui DuPont Poly). (Made by Chemical Co., Ltd.) and the like.

The MFR of the copolymer of ethylene and the copolymerizable monomer is not particularly limited. Usually, the lower limit of MFR (JIS K 7210, temperature: 190 ° C., load: 21.18N) is preferably 0.5 g / 10 minutes or more, more preferably 1.0 g / 10 minutes or more, and the upper limit is preferable. It is 15 g / 10 minutes or less, more preferably 10 g / 10 minutes or less.

The lower limit of the mass average molecular weight of the polyolefin resin is preferably 50,000 or more, more preferably 100,000 or more, and the upper limit is 700,000 or less, more preferably 600,000 or less, still more preferably 500,000. It is as follows. When the mass average molecular weight of the polyolefin resin is within the above range, desired mechanical properties such as mechanical properties and heat resistance can be exhibited, an appropriate melt viscosity can be obtained, and good molding processability can be obtained.

The method for producing the polyolefin resin is not particularly limited, and is represented by a known polymerization method using a known catalyst for olefin polymerization, for example, a multisite catalyst represented by a Ziegler-Natta type catalyst or a metallocene catalyst. Examples thereof include a slurry polymerization method, a solution polymerization method, a lumpy polymerization method, a gas phase polymerization method and the like using a single-site catalyst, and a lumpy polymerization method using a radical initiator.

The base film may contain particles for the purpose of roughening the surface of the film to impart slipperiness and for the main purpose of preventing scratches in each step.
The type of the particles is not particularly limited as long as the particles can be easily slippery. For example, inorganic particles such as silica calcium carbonate, magnesium carbonate, barium carbonate, calcium sulfate, calcium phosphate, magnesium phosphate, kaolin, aluminum oxide, titanium oxide, acrylic resin, styrene resin, urea resin, phenol resin, epoxy resin, benzoguanamine resin. Organic particles such as, etc. can be mentioned. These may be used alone or in combination of two or more of them.
The shape of the particles is not particularly limited. For example, it may be spherical, lumpy, rod-shaped, flat-shaped, or the like.
Further, the hardness, specific gravity, color and the like of the particles are not particularly limited. Two or more kinds of these series of particles may be used in combination, if necessary.

The average particle size of the particles is preferably 5.0 μm or less, more preferably 0.01 μm or more or 3.0 μm or less, and more preferably 0.5 μm or more or 2.5 μm or less. When the average particle size of the particles is 5 μm or less, the surface roughness of the base film does not become too rough. Therefore, in that respect, when the anchor layer or the inorganic layer is formed on the surface of the base film. Problems can be reduced.

The particle content is preferably 5% by mass or less, particularly 0.0003% by mass or more or 3% by mass or less, and among them, 0.01% by mass or more or 2% by mass or less. More preferred. By setting the particle content within the above range, it is possible to achieve both slipperiness and transparency of the film, which is preferable.

The method of adding the particles to the base film is not particularly limited, and a conventionally known method can be adopted.

If necessary, the base film may contain conventionally known antioxidants, antistatic agents, heat stabilizers, lubricants, dyes, pigments, ultraviolet absorbers and the like.

(Thickness of this base film)
The thickness of the base film is not particularly limited as long as it can be formed as a film, and is preferably 9 μm to 100 μm, particularly 12 μm or more or 75 μm or less, and 15 μm or more or 60 μm or less. It is even more preferable to have it.

The base film can be formed, for example, by forming a resin composition into a film shape by a melt film forming method or a solution film forming method. In the case of a multi-layer structure, co-extrusion may be performed.
Further, it may be uniaxially stretched or biaxially stretched, and is preferably a biaxially stretched film from the viewpoint of rigidity.

<This anchor layer>
The anchor layer (referred to as “the anchor layer”) constituting the laminated film is a layer having a function of enhancing the adhesiveness between the base film and the inorganic layer.

The anchor layer can usually be formed from an anchor coating agent.
The anchor coating agent includes solvent-based or water-based polyester, urethane resin, acrylic resin, vinyl alcohol resin, ethylene vinyl alcohol resin, vinyl modified resin, oxazoline group-containing resin, carbodiimide group-containing resin, epoxy group-containing resin, and isocyanate group. Examples thereof include a containing resin, an alkoxyl group-containing resin, a modified styrene resin, a modified silicone resin, and the like, and these can be used alone or in combination of two or more. Among them, at least one selected from polyester, urethane resin, acrylic resin, oxazoline group-containing resin, carbodiimide group-containing resin, epoxy group-containing resin, isocyanate-containing resin and copolymers thereof from the viewpoint of adhesion and heat resistance. It is preferable to use them alone or in combination of two or more. Among them, at least one resin selected from the group consisting of polyester, urethane resin and acrylic resin is preferable.

The anchor layer preferably contains a cured product obtained by curing the curable resin. Examples of the curable resin include a photocurable resin and a thermosetting resin, and among them, those containing an isocyanate compound are particularly preferable. At this time, the content of the isocyanate compound in the anchor layer is preferably 1 to 50 parts by mass with respect to 100 parts by mass of the curable resin, particularly 5 parts by mass or more or 40 parts by mass or less, and 10 parts by mass among them. It is more preferably more than parts by mass or less than 30 parts by mass.
Therefore, the anchor layer is preferably a layer formed by coating a resin composition containing a curable resin on the base film and then curing the film.

When the thickness of the anchor layer is 5.00 μm or less, the slipperiness is good, there is almost no peeling from the base film due to the internal stress of the anchor layer itself, and the thickness is 0.02 μm or more. If there is, it is preferable because a uniform thickness can be maintained.
From this point of view, the thickness of the anchor layer is preferably 0.02 to 5.00 μm, particularly 0.03 μm or more or 3.00 μm or less, and among them, 0.05 μm or more or 1.00 μm or less. More preferred.

The anchor layer preferably has a storage elastic modulus (E') at 120 ° C. of 10.0 MPa or more, particularly 12.0 MPa or more, particularly 14.0 MPa or more, and particularly 15.0 MPa or more. More preferred.
If the anchor layer has the above thickness and the above elastic modulus, the deformation of the base film during heat treatment can be alleviated by the anchor layer even when a base film having poor heat resistance is used. It is possible to prevent the generation of cracks in the inorganic layer during heat treatment, and it is possible to obtain the desired gas barrier property.

The anchor layer further preferably has a peak temperature of tangent loss (tan δ) of 60.0 ° C. or higher in dynamic viscoelasticity measurement, particularly 70.0 ° C. or higher, particularly 80.0 ° C. or higher, and particularly particularly. It is more preferably 85.0 ° C. or higher.

In order to impart the viscoelasticity to the anchor layer, for example, it is preferable that the anchor layer contains a cured product obtained by curing the curable resin. Therefore, it is preferable that the anchor layer is formed by coating a resin composition containing a heat or photocurable resin on the base film and curing the heat or photocurable resin with heat or light. .. However, the method of imparting the viscoelasticity to the anchor layer is not limited to this method.
Above all, it is particularly preferable to select and use an isocyanate compound as the thermosetting resin.

As described above, the polylactic acid film is formed by laminating an anchor layer having a storage elastic modulus at 120 ° C. of 10.0 MPa or more at a thickness of 0.02 μm or more and 5.00 μm or less as an anchor layer constituting the laminated film. Good barrier properties and adhesion can be obtained even when an inorganic substance-containing layer is provided on a base film having poor heat resistance such as (PLA) or a stretched polypropylene film (OPP).
The mechanism by which such good barrier properties can be exhibited can be inferred as follows.
Generally, when an inorganic substance-containing layer is vapor-deposited on a base film having poor heat resistance, the base film tends to shrink due to heat damage during the deposition.
Further, in general, when the anchor layer is interposed between the base material and the inorganic substance-containing layer, the adhesion between the base film and the inorganic substance-containing layer tends to be improved in many cases. Therefore, the force of the base film to shrink directly propagates to the inorganic substance-containing layer to generate cracks and the like, thereby lowering the barrier property.
On the other hand, in this laminated film, paying attention to the elastic modulus or tan δ (corresponding to Tg) of the anchor layer, the base film can be shrunk by setting the item to a certain value or more and a specific thickness or more. It is possible to give the anchor layer itself a force that can counteract the force. As a result, it can be inferred that the shrinkage of the base film can be alleviated, the generation of cracks in the inorganic substance-containing layer can be suppressed, and a good barrier property that can withstand heating can be obtained.

<Genuine inorganic layer>
The inorganic layer (referred to as "the present inorganic layer") constituting the present laminated film is a layer containing an inorganic substance, particularly an inorganic oxide as a main material.
The "main material" means a material that occupies 50% by mass or more, particularly 70% by mass or more, particularly 80% by mass or more, and 90% by mass or more (including 100% by mass) of the present inorganic material layer.

This inorganic layer is a layer capable of enhancing the property of suppressing gas permeation (also referred to as "gas barrier property"), particularly the water vapor barrier property. Further, in the case of this inorganic layer, higher gas barrier properties can be realized by containing alkali metal ions.

Examples of the inorganic substance as the main material constituting the inorganic substance layer include a group consisting of silicon oxide, silicon nitride, silicon oxide nitride, silicon oxide, silicon oxide carbide, aluminum oxide, aluminum nitride, aluminum oxide and aluminum oxide. One or more inorganic compounds selected from the above can be mentioned.

Examples of the inorganic layer include a PVD inorganic layer formed by a physical vapor deposition (PVD) method, a plasma-assisted vapor deposition inorganic layer formed by a plasma-assisted vapor deposition method, and a CVD inorganic substance formed by a chemical vapor deposition (CVD) method. A layer, a coated inorganic layer formed by a method in which inorganic particles are dispersed in an organic polymer and applied is preferable.
Here, a PVD inorganic layer, a plasma-assisted vapor-deposited inorganic layer, and a CVD inorganic layer will be described as typical examples of the present inorganic layer.

(PVD inorganic layer)
It is preferable that the present inorganic layer includes at least one PVD inorganic layer formed by the physical vapor deposition method (PVD) in that higher gas barrier properties can be exhibited.

As an example of the PVD inorganic layer, a layer composed of a silicon oxide represented by SiOx (1.0 <x ≦ 2.0) can be mentioned. At this time, if the x value (lower limit value) of SiOx becomes smaller, the gas permeability becomes smaller and the gas barrier property of the present inorganic layer can be enhanced, while the silicon oxide film itself becomes yellowish and transparent. It tends to be less sexual. From this point of view, x in the SiOx is more preferably 1.2 ≦ x ≦ 2.0, and more preferably 1.4 ≦ x ≦ 2.0.
The composition can be confirmed by XPS analysis or the like.

^{The preferable pressure at the time of forming the PVD inorganic layer is preferably 1 × 10 -7} Pa to 1 Pa, particularly 1 × 10 ^-6 or more, from the viewpoint of gas barrier property, vacuum exhaust capacity, and degree of oxidation of the SiOx layer to be formed. or 1 × 10 ^-1 Pa or less, and more preferably 1 × 10 ^-4 or more, or 1 × 10 ^-2 Pa or less therein.
The partial pressure at the time of introducing oxygen is preferably in the range of 10 to 90% with respect to the total pressure, and more preferably 20% or more or 80% or less.

As described above, the present inorganic layer preferably includes at least one PVD inorganic layer. At this time, the present inorganic layer may have a single-layer structure composed of a PVD inorganic layer, or may have the same or different composition from the CVD inorganic layer described later on the PVD inorganic layer in order to secure higher gas barrier properties. It may have a multi-layer (two or more layers) structure in which PVD inorganic layers are laminated. For example, a PVD inorganic layer and a CVD inorganic layer may be alternately formed (for example, a three-layer structure consisting of a PVD inorganic layer, a CVD inorganic layer, and a PVD inorganic layer). Further, by forming the CVD inorganic material layer on the PVD inorganic material layer, defects and the like generated in the PVD inorganic material layer are sealed, and the gas barrier property and the adhesion between layers tend to be improved.

(Plasma assisted vapor deposition inorganic material layer)
If the present inorganic layer is composed of the plasma-assisted vapor-deposited inorganic layer, the transparency can be improved without lowering the gas barrier property.
The "plasma-assisted thin-film deposition method" refers to a method in which a vapor-deposited material is vapor-deposited while being ionized by plasma during vacuum-film deposition, or gas ions are irradiated from a separately provided ion source.
If the present inorganic layer is formed by the plasma-assisted thin-film deposition method, oxygen can be efficiently taken into the present inorganic layer, and as described above, the transparency can be improved without lowering the gas barrier property.
A thin film obtained by ordinary vacuum vapor deposition has a smaller energy of flying particles than a thin film formed by sputtering or the like, and is not advantageous in terms of film strength and density. On the other hand, according to the plasma-assisted thin-film deposition method, since the vapor-deposited substance obtains energy, a thin film having high strength and density can be formed even in vacuum-film deposition. Further, since the excited species in the plasma are highly reactive, it is possible to form a thin film in which the evaporation source is arbitrarily oxidized, nitrided, or carbonized by introducing a gas such as oxygen, nitrogen, or acetylene. By providing the present inorganic layer by this method, there is also an advantage that a film can be formed faster than the sputtering or plasma CVD method.

As an example of the plasma-assisted vapor-deposited inorganic material layer, a layer composed of a silicon oxide represented by SiOx (1.0 <x ≦ 2.0) can be mentioned. As described above, if oxygen gas is introduced into the inorganic layer by the plasma-assisted thin-film deposition method, the oxygen molar ratio of silicon oxide can be increased, so x in the SiOx is set to 1.2 ≦ x ≦ 2.0. Further, since 1.4 ≦ x ≦ 2.0 can be set, the transparency can be further improved. The gas barrier property usually decreases as the oxygen molar ratio (x) increases. Excellent gas barrier properties can be maintained for this laminated film.

(CVD Inorganic Layer)
When the present inorganic layer includes at least one CVD inorganic layer, the CVD inorganic layer is composed of a thin film formed by chemically vapor deposition of at least one selected from a metal, a metal oxide, a metal nitride and a silicon compound. Is preferable.
As the metal oxide or the metal nitride, it is preferable to use the metal oxide, the nitride or a mixture thereof from the viewpoint of gas barrier property and adhesion. Further, it may be a metal oxide or a metal nitride obtained by plasma-decomposing an organic compound.
Further, from the viewpoint of gas barrier property and adhesion, it is also preferable to use a metal or compound such as silicon or aluminum.

As a preferable example of the present inorganic layer, a structure composed of a silicon compound such as silicon oxide, silicon oxide, silicon oxide, silicon oxide, silicon nitride, silicon nitride, and a thin film formed by chemically depositing at least one selected from aluminum oxide. Can be mentioned.
Examples of the silicon compound include silane, tetramethoxysilane, tetraethoxysilane, tetra n-propoxysilane, tetraisopropoxysilane, tetra n-butoxysilane, tetrat-butoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, and diethyldimethoxy. Silane, diphenyldimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, phenyltriethoxysilane, (3,3,3-trifluoropropyl) trimethoxysilane, hexamethyldisiloxane, bis (dimethylamino) dimethylsilane, bis (Dimethylamino) methylvinylsilane, bis (ethylamino) dimethylsilane, N, O-bis (trimethylsilyl) acetamide, bis (trimethylsilyl) carbodiimide, diethylaminotrimethylsilane, dimethylaminodimethylsilane, hexamethyldisilazane, hexamethylcyclotrisilazane , Heptamethyldisilazane, nonamethyltrisilazane, octamethylcyclotetrasilazane, tetrakisdimethylaminosilane, tetraisosianatosilane, tetramethyldisilazane, tris (dimethylamino) silane, triethoxyfluorosilane, allyldimethylsilane, allyltrimethylsilane , Benzyltrimethylsilane, bis (trimethylsilyl) acetylene, 1,4-bistrimethylsilyl-1,3-butadiine, di-t-butylsilane, 1,3-disilabtan, bis (trimethylsilyl) methane, cyclopentadienyltrimethylsilane, phenyl Dimethylsilane, phenyltrimethylsilane, propargyltrimethylsilane, tetramethylsilane, trimethylsilylacetylene, 1- (trimethylsilyl) -1-propine, tris (trimethylsilyl) methane, tris (trimethylsilyl) silane, vinyltrimethylsilane, hexamethyldisilane, octamethyl Cyclotetrasiloxane, tetramethylcyclotetrasiloxane, hexamethyldisiloxane, hexamethylcyclotetrasiloxane, M silicate 51 and the like can be mentioned.

The CVD inorganic layer preferably contains carbon. At that time, the carbon content of the CVD inorganic layer was 0.5 at. % Or more, preferably 1 at. % Or more, more preferably 2 at. It should be% or more.
Since the CVD inorganic layer contains a small amount of carbon, stress relaxation can be efficiently performed and curling of the barrier film itself can be reduced. On the other hand, from the viewpoint of gas barrier property, the carbon content in the CVD inorganic layer is 20 at. It is preferably less than%, and above all, 10 at. It is more preferably less than%, and among them, 5 at. Most preferably, it is% or less.
By setting the carbon content in the above range, the surface energy of the inorganic layers is increased, and the adhesion between the inorganic layers is improved, so that the bending resistance and peeling resistance of the barrier film are improved. In addition, "at.%" Indicates an atomic composition percentage (atomic%). Further, the composition can be confirmed by XPS analysis or the like.

The CVD inorganic layer can be formed by, for example, the method described in JP2013-226829.
For example, when a layer made of silicon oxide is formed by a chemical vapor deposition (CVD) method, a silicon compound can be used as a raw material in any state of gas, liquid, or solid under normal temperature and pressure. be able to. In the case of gas, it can be introduced into the discharge space as it is. In the case of a liquid or solid, it is preferable to vaporize it by means such as heating, bubbling, depressurization, and ultrasonic irradiation. Alternatively, it may be used after being diluted with a solvent. As the solvent, an organic solvent such as methanol, ethanol, n-hexane or a mixed solvent thereof can be used.

When performing the chemical vapor deposition (CVD) method, the chemical vapor deposition (CVD) is carried out while transporting the base film, particularly the base film provided with the anchor layer, at a speed of 100 m / min or more in a reduced pressure environment of 10 Pa or less. ) It is preferable to carry out the method.
The pressure when forming a thin film by chemical vapor deposition (CVD) is preferably performed under reduced pressure in order to form a dense thin film, and is preferably 10 Pa or less from the viewpoint of film forming speed and barrier properties. Of these, 1 × 10 ⁻² or more or 10 Pa or less, and among them, 1 × 10 ^-1 or more or 1 Pa or less is more preferable.

The CVD inorganic layer may be subjected to a cross-linking treatment by electron beam irradiation, if necessary, in order to improve water resistance and durability.

(Layer composition of this inorganic layer)
The inorganic layer may have a single-layer structure or a multi-layer structure having two or more layers.
For example, as an example of a multi-layer structure having two or more layers, one layer thereof is an inorganic substance, for example, an inorganic substance layer composed of only an inorganic oxide, and the other layer is an inorganic / organic mixed layer composed of an inorganic substance, for example, an inorganic oxide and an organic substance. For example,

By forming the present inorganic layer by mixing the organic substance with the inorganic substance, the present inorganic layer can be made into a relatively flexible layer. Therefore, by providing such a flexible layer, the gas barrier property can be enhanced. In some cases. That is, the coarse protrusions of the base film are the starting points, and minute defects called pinholes are generated on the surface of the inorganic layer, or the raw material is lumped and adheres to the surface of the inorganic layer during heat vapor deposition. Minor defects may occur, and the gas barrier property may decrease due to the passage of gas through the voids due to these defects. Therefore, by laminating and laminating the above-mentioned flexible layer on the surface, the defect can be filled and the gas barrier property may be enhanced.
The term "flexible layer" as used herein includes the meaning of a layer that relaxes the stress of the inorganic layer so that it can be used for applications that require flexibility, such as flexible applications.

As described above, in order to form a flexible layer, an organic substance may be mixed with the inorganic substance to form a layer, and the organic substance at that time includes, for example, an organic substance such as polyester resin, acrylic resin, urethane resin, and PVA. In addition, organic fillers can be mentioned.

(Thickness of inorganic layer)
The thickness of the inorganic layer (the total thickness of the inorganic layer when the inorganic layer has a multi-layer structure) is preferably 0.1 nm to 500 nm, particularly 1 nm or more or 300 nm or less, and 5 nm or more or 100 nm or less. It is even more preferable to have it.
When the thickness of the inorganic material layer is within the above range, it is possible to secure the desired gas barrier property.

(This crosslinked resin layer)
If necessary, the laminated film may further include a crosslinked resin layer (referred to as “the present crosslinked resin layer”) on the present inorganic material layer.

The crosslinked resin layer may be a layer containing a crosslinked resin formed by cross-linking the resin, and is preferably a layer having the crosslinked resin as a basic skeleton.

Since the crosslinked resin layer is more flexible than the inorganic layer, it can absorb the surface irregularities of the inorganic layer, thereby improving the gas barrier property. It is also possible to suppress yellowing or yellowish browning caused by the present inorganic layer.

(Composition of this crosslinked resin layer)
The crosslinked resin layer is a layer having a crosslinked resin structure formed by crosslinking and curing a crosslinkable resin composition containing a binder resin as a main component resin and other components such as a curing agent or a crosslinking initiator. Is preferable.
At this time, the "main component resin" means the resin having the highest content (mass%) among the resins constituting the main crosslinked resin layer. The content ratio of the crosslinked resin layer is preferably 50% by mass or more, particularly 70% by mass or more, particularly 80% by mass or more, and particularly preferably 90% by mass or more (including 100% by mass).

(Binder resin)
Examples of the binder resin include a water-soluble epoxy resin, a water-dispersible polyurethane resin, and a water-dispersible urethane acrylate, which will be described below.

[Water-soluble epoxy resin]
As the water-soluble epoxy resin, it is preferable to use a water-soluble epoxy resin which is a prepolymer having an epoxy group at the terminal.
Of these, those having an aromatic prepolymer chain are preferable. Specific examples include an epoxy resin having a glycidylamine moiety derived from metaxylylene diamine, an epoxy resin having a glycidylamine moiety derived from 1,3-bis (aminomethyl) cyclohexane, and glycidyl derived from diaminodiphenylmethane. Epoxy resin with amine moiety, glycidyl amine moiety and / or glycidyl ether moiety derived from paraaminophenol, epoxy resin with glycidyl ether moiety derived from bisphenol A, glycidyl ether moiety derived from bisphenol F Examples thereof include an epoxy resin having a glycidyl ether moiety derived from phenol novolac, an epoxy resin having a glycidyl ether moiety derived from phenol novolac, and an epoxy resin having a glycidyl ether moiety derived from resorcinol. Among these, an epoxy resin having a glycidylamine moiety derived from m-xylylenediamine is particularly preferable.

[Water-dispersible polyurethane resin]
As the water-dispersible polyurethane resin, a polyurethane compound obtained by reacting a polyol compound containing no carboxyl group in the molecule with a polyisocyanate compound is forcibly emulsified in water by using surface activity to obtain water dispersibility. Polyurethane resin can be mentioned. However, the present invention is not limited to this.

[Water-dispersed urethane acrylate]
The aqueous dispersion type urethane acrylate is obtained by mixing a urethane acrylate raw material, an emulsifier such as an anionic and / or nonionic reactive emulsifier, and an oil-soluble polymerization initiator, and using an emulsifier such as a homomixer or super. Examples thereof include urethane acrylate, which is an aqueous dispersion obtained by emulsion polymerization in a manner of dispersing while heat-treating with a sonic disperser or the like. However, the present invention is not limited to this.

As the urethane acrylate raw material, a radically polymerizable oligomer having two or more acryloyl groups or methacryloyl groups in one molecule can be used.
Examples of commercially available urethane acrylate products include Beam Set 505A-6 (manufactured by Arakawa Chemical Industry Co., Ltd.), Ebeclyl270 (manufactured by Daicel Industries, Ltd.), UA-160TM, UA-7100, (Shin Nakamura Chemical Industry Co., Ltd.), and the like. NS.

The emulsifier is not particularly limited as long as it can be used for emulsion polymerization.
Examples of the anionic reactive emulsifier include commercially available products such as Aqualon series: KH-05, KH-10, AR-10, AR-20 (trade name: manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.), Antox-MS-60, and the like. Antox-MS-2N (manufactured by Japan Emulsifier Co., Ltd.), Adecaria soap series: SE-10N, SE-20N, SR-10 (manufactured by ADEKA) can be mentioned. Among them, those made of sulfonate are preferable.
Examples of the nonionic reactive emulsifier include commercially available products such as Adecaria Soap Series: NE-10, NE-20, NE-30, ER-10, ER-20, ER-30, ER-40 (manufactured by ADEKA). , Latemul series: PD-420, PD-430, PD-450 (Kao) and the like.

Examples of the oil-soluble polymerization initiator include 2,2'-azobisisobutyronitrile, 2,2'-azobis- (2-methylpropanenitrile), and 2,2'-azobis- (2,4-dimethyl). Pentannitrile), 2,2'-azobis- (2-methylbutanenitrile), 1,1'-azobis- (cyclohexanecarbonitrile), 2,2'-azobis- (2,4-dimethyl-4-methoxyvalero) Azo (azobis nitrile) type initiators such as nitrile), 2,2'-azobis- (2,4-dimethylvaleronitrile), 2,2'-azobis- (2-amidinopropane) hydrochloride, peroxide, peroxide Benzoyl, cumenehydroperoxide, hydrogen peroxide, acetyl peroxide, lauroyl peroxide, persulfate (eg ammonium persulfate), peracid ester (eg t-butylperoctate, α-cumylperoxypivalate and t-butyl) Peroxide type initiators such as peroctate) can be exemplified.

(Curing agent or cross-linking initiator)
The curing agent or the cross-linking initiator is preferably used as appropriate depending on whether a cross-linking method of thermal cross-linking or photo-crosslinking is selected, and what is used as the binder resin.
For example, when a water-soluble epoxy resin is used as the binder resin, it is preferable to use an amine compound as a curing agent, and among them, aromatic amines such as meta-phenylenediamine, diaminodiphenylmethane, and diaminodiphenylsulfone are preferable.

When the crosslinkable resin composition is photocrosslinked, it is preferable to add a photopolymerization initiator.
The photopolymerization initiator is not particularly limited, and examples thereof include a ketone-based photopolymerization initiator and an amine-based photopolymerization initiator.

(solvent)
As the aqueous solvent, water or an alcohol solvent can be used as the main solvent.
Specific examples of the alcohol solvent include methanol, ethanol, isopropyl alcohol, butanol and the like. However, it is not limited to these.

(Other ingredients)
The crosslinked resin layer may contain other components or materials in addition to the above-mentioned materials.
Examples of the "other component or material" include an inorganic filler, an oxygen scavenger, a coupling agent, a curing accelerator, and the like.

The inorganic filler contains an inorganic filler such as silica, alumina, mica, talc, aluminum flakes, and glass flakes in order to improve various performances such as gas barrier property, impact resistance, and heat resistance of the crosslinked resin layer. You may be doing it. Further, when considering the transparency of the top coat layer, it is preferable that the inorganic filler is in the form of a flat plate.

The oxygen scavenger may be any compound having an oxygen scavenging function. For example, low-molecular-weight organic compounds that react with oxygen such as hindered phenols, vitamin C, vitamin E, organic phosphorus compounds, gallic acid, and pyrogallol, and transition metal compounds such as cobalt, manganese, nickel, iron, and copper can be mentioned. Can be done.

The coupling agent can be contained in the crosslinked resin layer as needed from the viewpoint of improving the adhesion between the crosslinked resin layer and the inorganic material layer or improving the gas barrier property.
As the coupling agent, a coupling agent such as a silane coupling agent or a titanium coupling agent may be added.
As the coupling agent, a commercially available product can be used. Specifically, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, N- ( 2-Aminoethyl) -3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, N, N'-bis [3-trimethoxysilyl] propyl] Amino-based such as ethylenediamine Silane coupling agent, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, etc. Epoxy silane coupling agents, methacryloxy silane coupling agents such as 3-methacryloxypropyltrimethoxysilane, mercapto-based silane coupling agents such as 3-mercaptopropyltrimethoxysilane, 3-isocyanoxidetriethoxysilane and the like. Silane-based silane coupling agents, aminosilane-based coupling agents such as SH-6026 and Z-6050 manufactured by Toray Dow Corning Co., Ltd., amino groups such as KP-390 and KC-223 manufactured by Shin-Etsu Chemical Co., Ltd. Examples include the contained alkoxysilane.
Above all, those having an organic functional group that reacts with the binder resin composition of the crosslinked resin layer are desirable.
The amount of the coupling agent added is preferably in the range of 0.01% by mass to 5.0% by mass based on the total mass of the binder resin composition.

The curing accelerator is a curing accelerator such as N-ethylmorpholin, dibutyltin dilaurate, cobalt naphthenate, stannous chloride, and benzyl alcohol so that the crosslinkable resin composition can be crosslinked at a low temperature. Organic solvents such as zinc phosphate, iron phosphate, calcium molybdate, vanadium oxide, water-dispersed silica, rust-preventive additives such as fumed silica, phthalocyanine-based organic pigments, condensed polycyclic organic pigments and other organic pigments, It is also possible to add each component such as an inorganic pigment such as titanium oxide, zinc oxide, calcium carbonate, barium sulfate, alumina, and carbon black in a required ratio amount.

(Amount of each component)
The ratio of the binder resin to the total solid component (100 parts by mass) in the crosslinkable resin composition is preferably 20 parts by mass or more, more preferably 30 parts by mass or more, and 90 parts by mass or less. It is preferably 80 parts by mass or less, and more preferably 80 parts by mass or less. When two or more kinds of binder resins are used in combination, the ratio of the total amount thereof is preferably within the above range. When two or more kinds of binder resins are used in combination, the ratio of the total amount thereof is preferably within the above range.

The ratio of the curing agent or the cross-linking initiator to the total solid component (100 parts by mass) in the crosslinkable resin composition is preferably 5 parts by mass or more, particularly 10 parts by mass or more, and particularly 20 parts by mass or more. It is even more preferable to have it. On the other hand, the upper limit is preferably 80 parts by mass or less, more preferably 70 parts by mass or less, and particularly preferably 60 parts by mass or less.

The ratio of the binder resin and the solid components other than the curing agent or the cross-linking initiator to the total solid components (100 parts by mass) in the crosslinkable resin composition is preferably 0.01 parts by mass or more and 10 parts by mass or less, and 0 It is more preferably 1 part by mass or more or 10 parts by mass or less, and more preferably 1 part by mass or more or 10 parts by mass or less.

<Laminated structure of this laminated film>
Since the laminated film may have a structure in which the anchor layer and the inorganic layer are laminated in this order on one side (referred to as "front side") of the base film, the back side of the base film or the back side of the base film may be provided. An "other layer" such as a crosslinked resin layer may be provided between the anchor layer and the inorganic material layer or on the surface side of the inorganic material layer.

<Thickness of this laminated film>
By adjusting the overall thickness of the laminated film, it is possible to suppress the occurrence of wrinkles while ensuring light transmission. From this point of view, the total thickness of the laminated film is preferably 10 μm or more, particularly preferably 15 μm or more or 500 μm or less, particularly 20 μm or more or 250 μm or less, and particularly preferably 23 μm or more or 125 μm or less.

<Characteristics of this laminated film>
The laminated film can have a water vapor transmittance (WvTR) of 6.0 g / m ² / day or less at a ^{temperature of 40 ° C. and a relative humidity of 90%, preferably 4.0 g / m 2} / day or less, among which. Particularly preferably, it can be 2.0 g / m ² / day or less.
The temperature 25 ° C., the oxygen transmission rate ^{(cc / (m 2 · 24hr} · atm)) can be ^{8.0cc / (m 2 · 24hr ·} atm) or less under a relative humidity of 80%, preferably ^{is, 6.0cc / (m 2 · 24hr} · atm) or less, particularly preferably among them may be a ^{2.0cc / (m 2 · 24hr ·} atm) or less.

<Manufacturing method of this laminated film>
As an example of the method for producing the present laminated film, a method of forming an anchor layer on one side of the base film as needed and forming the present inorganic layer on the surface of the anchor layer can be mentioned. However, the method is not limited to this method.

The anchor layer can be formed by applying the above-mentioned anchor coating agent to one side of the base film and drying it if necessary.
As described above, the inorganic layer is formed by, for example, a physical vapor deposition (PVD) method, a plasma-assisted vapor deposition method, a chemical vapor deposition (CVD) method, or a method in which inorganic particles are dispersed in an organic polymer and applied. Can be formed by

<< This film laminate >>
Next, as an example of the embodiment using the present laminated film, a film laminate using the present laminated film (referred to as “the present film laminate”) will be described.

As an example of the present film laminate, the outermost surface of the laminated film, that is, the surface of the present inorganic layer, which has a structure in which an anchor layer and an inorganic layer are sequentially laminated on at least one side of the main laminated film, that is, the base film (1). A film laminate having a structure in which a base film (2) is bonded to the surface of the crosslinked resin layer via an adhesive layer can be mentioned.

<Base film (2)>
As the base film (2), the base film (1), that is, the one described as the present base film can be used.

Further, as the base film (2), a biodegradable film or a polyolefin film can also be used.
The biodegradable film means a film having a layer containing a biodegradable resin as a main component resin regardless of whether the film has a single-layer structure or a multi-layer structure. Preferably, the film is mainly composed of a biodegradable resin as a main component resin. Among them, regardless of whether the base film (2) has a single-layer structure or a multi-layer structure, it is preferable that the main component resin of each layer is a biodegradable resin.

Here, the biodegradable resin means a resin having biodegradability, and the "biodegradable" means a property of being finally decomposed into water and carbon dioxide by the action of microorganisms, which is preferable. Is a property that satisfies the condition that a 100 mm square film has a remaining 10% of a 2 mm flue within 12 weeks on a pilot scale under an aerobic composting environment of 58 ° C. described in ISO 16929 or JIS K 6952.
Examples of the biodegradable resin include polylactic acid (PLA), polycaprolactone (PCL), polybutylene succinate (PBS), polybutylene succinate adipate (PBSA), polybutylene adipate, polyethylene succinate (PES), 3-. Examples thereof include biodegradable aliphatic polyesters such as hydroxybutyrate-co-3-hydroxyhexanoate polymer (PHBH), and biodegradable aliphatic aromatic polyesters such as polybutylene adipate terephthalate (PBAT).

The polyolefin film used for the base film (2) is the same as the polyolefin used for the base film (1).

The structure and thickness of the base film (2) are the same as those of the base film (1).

<Adhesive layer>
The adhesive layer of the present film laminate can be formed by using a known adhesive composition. From the viewpoint of achieving both adhesiveness and barrier property, it is preferable to use an adhesive composition containing a binder resin and a curing agent or a crosslinking initiator, and the binder resin is, for example, a water-soluble epoxy resin or a water-dispersible polyurethane resin. , Water-dispersed urethane acrylate oligomers and the like are preferably used.

<Thickness of this film laminate>
By adjusting the overall thickness of the film laminate, it is possible to suppress the occurrence of wrinkles while ensuring light transmission. From this point of view, the total thickness of the present film laminate is preferably 40 μm or more, particularly preferably 50 μm or more or 500 μm or less, and particularly preferably 50 μm or more or 250 μm or less, particularly 50 μm or more or 125 μm or less.

<< Applications of this laminated film and this laminated film >>
The laminated film and the laminated film are used for applications that require blocking of various gases such as water vapor and oxygen, for example, for packaging materials that require blocking of various gases, for example, for preventing deterioration of foods, industrial products, pharmaceuticals, and the like. It can be widely used as a packaging material. In addition to packaging applications, it is suitable for various members such as liquid crystal display elements, solar cells, electromagnetic wave shields, touch panels, EL substrates, and color filters.

<< Explanation of words >>
In the present invention, the term "film" shall include the "sheet", and the term "sheet" shall include the "film".
Further, when the term "panel" is used as in the case of an image display panel, a protective panel, etc., it includes a plate body, a sheet, and a film.
Further, in the present laminated film, the base film side is referred to as a lower side or a back surface side, and the opposite side is referred to as an upper side or a front surface side.

In the present invention, when "X to Y" (X, Y are arbitrary numbers) is described, it means "X or more and Y or less" and "preferably larger than X" or "preferably Y". It also includes the meaning of "smaller".
Further, when "X or more" (X is an arbitrary number) is described, it includes the meaning of "preferably larger than X" and is described as "Y or less" (Y is an arbitrary number) unless otherwise specified. In this case, unless otherwise specified, it also includes the meaning of "preferably smaller than Y".

Hereinafter, the present invention will be specifically described with reference to Examples. However, the present invention is not limited to the following examples.
The measurement method and evaluation method used in the present invention are as follows.

(1) Film thickness of the inorganic layer formed by the vacuum deposition method (PVD) The film thickness of the inorganic layer was measured using fluorescent X-rays. This method utilizes the phenomenon that when an atom is irradiated with X-rays, it emits fluorescent X-rays peculiar to that atom. The number (amount) of atoms is known by measuring the emitted fluorescent X-ray intensity. Can be done. Specifically, thin films of two known thicknesses were formed on the film, specific fluorescent X-ray intensities emitted from each were measured, and a calibration curve was created from this information. Then, the fluorescence X-ray intensity of the measurement sample was measured in the same manner, and the film thickness was measured from the calibration curve.

(2) Dynamic Viscoelasticity Measurement The anchor coating liquid used in Examples and Comparative Examples was dried at 80 ° C. to prepare a sheet having a thickness of 200 μm. The sheet is measured for viscoelasticity using a dynamic viscoelasticity measuring device "DVA-200" manufactured by IT Measurement Control Co., Ltd. under the conditions of a frequency of 1 Hz, a heating rate of 3 ° C./min, and a measurement temperature of -50 to 200 ° C. Then, the storage elastic modulus and the peak temperature of the loss tangent (tan δ) at 120 ° C. were determined.

(3) Moisture vapor transmission rate (WvTR)
For Examples 3 and 6, the prepared film laminate (sample) was used as a measurement sample, and for other Examples and Comparative Examples, the prepared laminated film (sample) was used as a measurement sample.
In the water vapor permeability measuring device DELTAPERM (manufactured by Technolux), the inorganic layer side is for the laminated film (measurement sample), the PBS film side or CPP film side is for the film laminate (measurement sample), and the detector side (base film is). ^{The water vapor transmission rate (g / m 2} / day) was measured under the conditions of a temperature of 40 ° C. and a relative humidity of 90% RH.
In the table, when the measurement target of the water vapor transmittance, that is, the measurement sample is a laminated film, the configuration at the time of barrier measurement is shown as "film", and when it is a film laminated body, it is shown as "laminated body".

(4) Oxygen Permeability For Examples 3 and 6, the prepared film laminate (sample) was used as a measurement sample. For other examples and comparative examples, measurement samples were prepared as follows. That is, a urethane adhesive (AD900 and CAT-RT85 manufactured by Toyobo Co., Ltd.) is applied to the surface of a non-axially stretched polypropylene (CPP) film (“P1146” manufactured by Toyobo Co., Ltd.) having a thickness of 60 μm as a laminating film. An adhesive layer having a thickness of about 3 μm was formed by applying and drying a mixture (blended at a ratio of 10: 1.5), and a laminated film (sample) produced in each Example / Comparative Example was formed on this adhesive layer. ) Was laminated on the surface side of the inorganic layer, and the obtained film laminate was used as a measurement sample.
For each film laminate (measurement sample), according to the JIS K 7126B method, an oxygen transmission rate measuring device (“OX-TRAN 2/21 type oxygen transmission rate measuring device” manufactured by MOCON) was used at a temperature of 25 ° C. oxygen transmission rate ^{(cc / (m 2 · 24hr} · atm)) was measured under the conditions of a relative humidity of 80%.

(5) Laminate strength Similar to the measurement of oxygen permeability, the prepared film laminate (sample) was used as the measurement sample for Examples 3 and 6, and the measurement sample was used for the other Examples and Comparative Examples as described above. Was produced.
Each film laminate (measurement sample) is cut into strips with a width of 15 mm, a part of the end is peeled off, and a tensile tester (“STA-1150” manufactured by Orientec Co., Ltd.) is used to achieve a speed of 300 mm / min. The laminate strength (g / 15 mm) after retort was measured by peeling the CPP film by 180 °.

<Preparation of anchor coating liquid>
(Preparation of anchor coating liquid 1)
An amorphous polyester resin (Byron 200 manufactured by Toyobo Co., Ltd.) and an isocyanate compound (Coronate L manufactured by Tosoh Co., Ltd.) were blended in a 10: 1 mass ratio to prepare an anchor coating liquid 1.

(Preparation of anchor coating liquid 2)
An amorphous polyester resin (Byron 103 manufactured by Toyobo Co., Ltd.) and an isocyanate compound (Coronate L manufactured by Toyobo Co., Ltd.) were blended in a 10: 1 mass ratio to prepare an anchor coating liquid 2.

(Preparation of anchor coating liquid 3)
An amorphous polyester resin (Byron 300 manufactured by Toyobo Co., Ltd.) and an isocyanate compound (Coronate L manufactured by Tosoh Co., Ltd.) were blended in a 10: 1 mass ratio to prepare an anchor coating liquid 3.

(Preparation of crosslinked resin layer composition)
Hydrogenated XDI (1,4-bis (isocyanate methyl) cyclohexane) 439.1 g, dimethylol propionic acid 35.4 g, ethylene glycol 61.5 g and acetonitrile 140 g as a solvent were mixed and mixed in a nitrogen atmosphere at 70 ° C. for 3 hours. The reaction was carried out to obtain a carboxyl group-containing polyurethane prepolymer solution. The carboxyl group-containing polyurethane prepolymer solution was then neutralized at 50 ° C. with 24.0 g of triethylamine. 267.9 g of this polyurethane prepolymer solution was dispersed in 750 g of water by a homodisper, a chain extension reaction was carried out with 35.7 g of 2-[(2-aminoethyl) amino] ethanol, and latex was distilled off. An aqueous dispersion of a polyurethane resin having a solid content of 25% by mass was obtained. A commercially available 3-glycidyloxypropyltrimethoxysilane was added to this aqueous dispersion in a mass ratio of 4 wt% to prepare a crosslinked resin layer composition.

<Example 1>
Poly-L-lactic acid (Lacty 1012 manufactured by Shimadzu Corporation) having a mass average molecular weight of 200,000 was extruded by T-die with a 60 mmφ single-screw extruder and then rapidly cooled with a cast roll to obtain a sheet. Next, this sheet was longitudinally stretched 2.5 times at 70 ° C. using a film tenter manufactured by Mitsubishi Heavy Industries, Ltd., then laterally stretched 2.5 times at 70 ° C., and then stretched 2.5 times at 120 ° C. for 30 seconds. Heat treatment (heat fixation) was carried out to obtain a polylactic acid film (base film (1)) having a thickness of 20 μm.
Next, one side of this polylactic acid film is subjected to corona treatment, the anchor coating liquid 1 is applied to the corona surface, and the film is dried at 80 ° C. for 1 minute to form an anchor layer having a thickness (after drying) of 0.03 μm. bottom.
Next, SiO is vaporized by a heating method under a vacuum of ^{2 × 10 -3} Pa using a vacuum vapor deposition apparatus _{to form a SiO ×} thin film layer (inorganic material layer) having a thickness of 30 nm on the anchor layer, and a laminated film is formed. (Sample) was obtained.

<Example 2>
In Example 1, a laminated film (sample) was obtained in the same manner except that the thickness of the anchor layer (after drying) was 0.10 μm.

<Example 3>
A polybutylene succinate (PBS) film having a thickness of 30 μm was used as the base film (2) on the surface _{of the SiO x} thin film layer of the laminated film (sample) produced in Example 1, and the film laminate (sample) was laminated. ) Was obtained.

<Example 4>
A laminated film (sample) was obtained in the same manner as in Example 1 except that a biaxially stretched polypropylene film (FOR manufactured by Futamura Chemical Co., Ltd., thickness 20 μm) was used as the base film (1) in Example 1. ..

<Example 5>
In Example 4, a laminated film (sample) was obtained in the same manner as in Example 4 except that the crosslinked resin layer composition was applied and dried on _{the SiO x thin film layer to form a crosslinked resin layer having a thickness of 0.5 μm.} rice field.

<Example 6>
The crosslinked resin layer surface of the laminated film (sample) produced in Example 4 was laminated with an unstretched polypropylene (CPP) film having a thickness of 60 μm as the base film (2) to obtain a film laminate (sample). Obtained.

<Comparative example 1>
A laminated film (sample) was obtained in the same manner as in Example 1 except that the anchor coating liquid 2 was used instead of the anchor coating liquid 1 in Example 1.

<Comparative example 2>
In Example 1, a laminated film (sample) was obtained in the same manner as in Example 1 except that the anchor coating liquid 3 was used instead of the anchor coating liquid 1.

<Comparative example 3>
In Example 1, a laminated film (sample) was obtained in the same manner as in Example 1 except that the thickness of the anchor layer (after drying) was 0.01 μm.

<Comparative example 4>
A laminated film (sample) was obtained in the same manner as in Example 1 except that the anchor layer was not formed in Example 1.

<Comparative example 5>
A laminated film (sample) was obtained in the same manner as in Example 4 except that the anchor coating liquid 2 was used instead of the anchor coating liquid 1 in Example 4.

<Evaluation result>
The characteristics of each laminated film and film laminate obtained in the above Examples and Comparative Examples are shown in Table 1 below.

In the table, "PLA" indicates a polylactic acid film, "OPP" indicates a stretched polypropylene film, "CPP" indicates a non-stretched polypropylene film, and "PBS" indicates polybutylene succinate.

<Discussion>
It was found that in Comparative Examples 1, 2 and 5, since the elastic modulus of the anchor layer did not satisfy the predetermined range, it was affected by the shrinkage of the base film and the barrier property was lowered. Further, it was found that in Comparative Example 3, since the thickness of the anchor layer was out of the range, it was affected by the shrinkage of the base film and the barrier property was lowered. On the other hand, in each of the examples, the elastic modulus of the anchor layer and the coating thickness both satisfied the range, so that the barrier property was good.

Based on the above examples and the test results conducted by the present inventor so far, an anchor layer having a storage elastic modulus at 120 ° C. of 10.0 MPa or more is provided with a thickness of 0.02 μm or more and 5.00 μm or less. , It was found that good barrier properties and adhesion can be obtained even when an inorganic substance-containing layer is provided on a base film having poor heat resistance such as a polylactic acid film (PLA) or a stretched polypropylene film (OPP).

As a mechanism (guess) that can exhibit good barrier properties, if the elastic modulus of the anchor layer is at least a certain value and at least a specific thickness, a force that can counteract the shrinkage force of the base film is used. It can be provided to the anchor layer itself, and it is presumed that the anchor layer can alleviate the shrinkage of the base film during heating. That is, since the anchor layer functions as a so-called shrinkage relaxation layer, it is presumed that the generation of cracks in the inorganic substance-containing layer can be suppressed even during heating, and the barrier property is improved.

The laminated film and film laminate of the present invention can be widely used for packaging articles that require blocking of various gases such as water vapor and oxygen, for example, as a packaging material for preventing deterioration of foods, industrial products, pharmaceuticals, and the like. can. In addition to packaging applications, it can also be suitably used for various members such as liquid crystal display elements, solar cells, electromagnetic wave shields, touch panels, EL substrates, and color filters.

Claims (9)

A laminated film having a structure in which an anchor layer and an inorganic layer are laminated in this order on at least one side of the base film (1), and the storage elastic modulus (E') of the anchor layer at 120 ° C. is 10. A laminated film having a thickness of 0 MPa or more and an anchor layer having a thickness of 0.02 to 5.00 μm. The laminated film according to claim 1, wherein the base film (1) is a polylactic acid film or a polyolefin film. The laminated film according to claim 1 or 2, wherein the peak temperature of the loss tangent (tan δ) in the dynamic viscoelasticity measurement of the anchor layer is 60.0 ° C. or higher. The gas barrier film according to any one of claims 1 to 3, wherein the anchor layer is made of at least one resin selected from the group consisting of polyester resin, urethane resin and acrylic resin. The gas barrier film according to any one of claims 1 to 4, wherein the anchor layer contains an isocyanate compound. Claimed that the inorganic layer contains at least one inorganic compound selected from silicon oxide, silicon nitride, silicon oxide nitride, silicon oxide, silicon oxide nitride, aluminum oxide, aluminum nitride, aluminum oxide and aluminum oxide. Item 4. The gas barrier film according to any one of Items 1 to 5. The laminated film according to any one of claims 1 to 6, further comprising a crosslinked resin layer on the inorganic material layer. A film laminate having a structure in which a base film (2) is bonded to the outermost surface of the laminated film according to any one of claims 1 to 7 via an adhesive layer. The film laminate according to claim 8, wherein the base film (2) is a biodegradable film or a polyolefin film.