JP2021119033A - Multi-layer structure, and packaging material, vacuum packaging bag and vacuum insulation body including said multi-layer structure - Google Patents

Abstract

To provide a multilayer structure, packaging material and vacuum insulation body that has an excellent adhesion between a substrate and a vapor-deposited layer under a harsh condition while maintaining the adhesion between the substrate and the vapor-deposited layer under a normal condition.SOLUTION: Provided is a multilayer structure that has a structure (XY) in which an aluminum vapor deposition layer (Y) is laminated on at least one surface of a substrate (X) made of a film containing a vinyl alcohol-based polymer as a main component, and in which the surface roughness (Ra) of the structure (XY) on the surface side of the aluminum vapor deposition layer (Y) measured in accordance with JIS B0601: 2001 by AFM (atomic force microscope) is 3.0 nm or more and 50 nm or less.SELECTED DRAWING: None

Description

The present invention relates to a multi-layer structure having an aluminum-deposited layer, a packaging material including the multi-layer structure, a vacuum packaging bag, and a vacuum heat insulating body.

Insulation bodies made of urethane foam (polyurethane foam) are used as heat insulating materials for refrigerators, heat insulating panels for houses, and the like. In recent years, a vacuum insulator has also been used as an alternative insulator. The vacuum insulation can provide the same insulation properties as the insulation made of urethane foam with a thinner and lighter insulation. The vacuum heat insulating body is expanding its use and demand as a heat insulating body used for heat insulating heat transfer equipment such as heat pump application equipment, heat storage equipment, living space, vehicle interior space, and the like.

Examples of the vacuum heat insulating body include a configuration including a vacuum packaging bag and a core material arranged inside surrounded by the vacuum packaging bag. One of the characteristics required for a vacuum packaging bag used for a vacuum insulation body is gas barrier property. Therefore, a vacuum packaging bag having an enhanced gas barrier property and a gas barrier film used for the vacuum packaging bag have been studied, and for example, a film provided with an aluminum vapor deposition layer or a silica vapor deposition layer has been provided.

Since these vapor-deposited layers are usually thin layers having a thickness of about several tens of nm to several hundreds of nm, in order to produce a film having a stable barrier property, adhesion with a base film is required. It was necessary to secure enough. For example, in Patent Document 1, a vapor-deposited film in which a vapor-deposited layer is laminated on a base film containing a vinyl alcohol-based polymer and a saturated ketone, wherein the saturated ketone content is 0.01 ppm or more and 100 ppm or less. It is described that the film has excellent adhesion of the vapor-deposited layer to the base film.

Japanese Unexamined Patent Publication No. 2015-071248

However, the above-mentioned conventional film may not have sufficient adhesion between the base material and the vapor-deposited layer under more severe conditions such as long-term use and high temperature and high humidity. For example, the above-mentioned conventional film is used as a vacuum packaging bag. When a vacuum-insulated body is produced, the heat insulating performance may be significantly deteriorated by using it under harsh conditions.

The present invention has been made based on the above circumstances, and an object of the present invention is to maintain the adhesion between the base material and the vapor-deposited layer under normal conditions and the adhesion between the base material and the vapor-deposited layer under harsh conditions. It is an object of the present invention to provide a multi-layer structure excellent in the above, and a packaging material, a vacuum packaging bag and a vacuum heat insulating body provided with the multi-layer structure.

That is, the present invention has a structure (XY) in which an aluminum vapor deposition layer (Y) is laminated on at least one surface of a base material (X) made of a film containing a vinyl alcohol polymer as a main component. , The surface roughness (Ra) by AFM (Atomic Force Microscope) measured according to JIS B0601: 2001 on the surface side of the aluminum vapor deposition layer (Y) of the structure (XY) is 3.0 nm or more and 50 nm or less. Structure;
[2] The multilayer structure of [1], wherein the vinyl alcohol-based polymer is an ethylene-vinyl alcohol copolymer having an ethylene unit content of 10 to 65 mol% and a saponification degree of 90 mol% or more.
[3] The multilayer structure of [1] or [2] in which the average thickness of the aluminum-deposited layer (Y) is 15 nm or more and 150 nm or less;
[4] The multilayer structure according to any one of [1] to [3], wherein the aluminum vapor deposition layer (Y) is laminated on both sides of a base material (X) made of a film containing a vinyl alcohol polymer as a main component;
[5] Any of [1] to [4], wherein the oxygen permeability at 20 ° C. and 85% RH measured according to JIS K7126-2: 2006 is 1.5 cc / m ^{2 · day · atm or less.} Multi-layer structure;
[6] A base material (X) made of a film containing a vinyl alcohol-based polymer as a main component and an aluminum-deposited layer (Y) measured in accordance with JIS K6854-3: 1999 while dropping water on the peeling interface. The multilayer structure according to any one of [1] to [5], which has a T-type peeling strength of 250 gf / 15 mm or more.
[7] The multilayer structure according to any one of [1] to [6], which has a structure in which a layer (Z) containing an organic polymer is laminated on one surface of an aluminum vapor-deposited layer (Y);
[8] The method for producing a multilayer structure according to any one of [1] to [7], wherein the surface temperature of the base material (X) made of a film containing a vinyl alcohol polymer as a main component is 60 ° C. or less. A method for manufacturing a multilayer structure, comprising a step of forming an aluminum vapor-deposited layer (Y) in a state;
[9] A packaging material containing the multilayer structure according to any one of [1] to [7];
[10] A vacuum packaging bag in which the inside of the packaging material of [9] is decompressed;
[11] The vacuum packaging bag of [10] has a core material inside, and is a vacuum insulation body;
Is achieved by.

According to the present invention, the multilayer structure and the multilayer structure having excellent adhesion between the substrate and the vapor deposition layer under harsh conditions while maintaining the adhesion between the substrate and the vapor deposition layer under normal conditions are provided. Packaging materials, vacuum packaging bags and vacuum insulation can be provided.

It is the schematic which shows an example of the melt extrusion apparatus which forms a film of a base material (X).

Hereinafter, embodiments of the present invention will be described. In the following description, a specific material (compound or the like) may be exemplified as a material exhibiting a specific function, but the present invention is not limited to the mode in which such a material is used. Further, as for the illustrated materials, unless otherwise specified, one type may be used alone, or two or more types may be used in combination.

The multilayer structure of the present invention has a structure (XY) in which an aluminum vapor deposition layer (Y) is laminated on at least one surface of a base material (X) made of a film containing a vinyl alcohol polymer as a main component. The surface roughness (Ra) by AFM (atomic force microscope) measured according to JIS B0601: 2001 on the surface side of the aluminum vapor deposition layer (Y) of the structure (XY) is 3.0 nm or more and 50 nm or less. In particular, the surface roughness (Ra) measured by AFM (atomic force microscope) on the surface side of the aluminum vapor deposition layer (Y) of the structure (XY) in accordance with JIS B0601: 2001 shall be 3.0 nm or more and 50 nm or less. Therefore, the adhesion between the base material (X) and the layer (Y) under harsh conditions tends to be good. The reason is not clear, but when the surface roughness (Ra) of the base material (X) exceeds a specific value, the boundary area between the base material (X) and the layer (Y) is increased and vapor deposition is performed. The increase in the anchoring effect of aluminum is considered to be one factor. Hereinafter, in the present specification, "adhesion between the base material (X) and the layer (Y) under harsh conditions" may be abbreviated as "adhesion under harsh conditions". Since the excellent adhesion under harsh conditions tends to maintain the performance for a long period of time under general-purpose conditions, for example, the vacuum packaging bag and the vacuum insulator of the present invention have stable performance for a longer period of time. Will be able to demonstrate.

[Base material (X)]
The multilayer structure of the present invention has a base material (X) made of a film containing a vinyl alcohol-based polymer as a main component. Here, "mainly composed" means that the proportion of the vinyl alcohol-based polymer in the film constituting the base material (X) is more than 50% by mass, and the proportion is 70% by mass or more. Preferably, 90% by mass or more is more preferable, 95% by mass or more is further preferable, and the base material (X) may be a film composed substantially only of a vinyl alcohol-based polymer. When the multilayer structure of the present invention has a base material (X), the gas barrier property of the multilayer structure of the present invention and the adhesion under harsh conditions tend to be good.

The vinyl alcohol-based polymer may have a vinyl alcohol unit obtained by saponifying the vinyl ester unit. For example, polyvinyl alcohol (hereinafter, may be abbreviated as "PVA") or ethylene-vinyl. Examples thereof include alcohol copolymers (hereinafter, may be abbreviated as "EVOH"). The vinyl alcohol-based polymer may be used alone or in combination of two or more.

PVA is produced by homopolymerizing a vinyl ester such as vinyl acetate and then saponifying it. Further, the PVA may be a modified PVA. For example, even if it is produced by copolymerizing vinyl acetate and an unsaturated monomer copolymerizable with vinyl acetate and then saponifying the PVA, the PVA is later added. It may be produced by modification, and the amount of modification is usually less than 10 mol%.

Examples of the unsaturated monomer copolymerizable with the vinyl acetate include olefins such as ethylene, propylene, isobutylene, α-octene, α-dodecene and α-octadecene, 3-butene-1-ol and 4-pentyne. Hydroxy group-containing α-olefins such as -1-ol and 5-hexene-1-ol and derivatives such as allyls thereof, acrylic acid, methacrylic acid, crotonic acid, maleic acid, maleic anhydride, itaconic acid, and undecylene acid. Unsaturated acids such as, salts thereof, monoesters, nitriles such as dialkyl ester, acrylonitrile, metaacrylonitrile, amides such as diacetoneacrylamide, acrylamide, methacrylicamide, ethylenesulfonic acid, allylsulfonic acid, methallylsulfonic acid. Olefin sulfonic acids such as or salts thereof, alkyl vinyl ethers, dimethylallyl vinyl ketone, N-vinylpyrrolidone, vinyl chloride, vinylethylene carbonate, 2,2-dialkyl-4-vinyl-1,3-diokinlane, glycerin monoallyl ether. , 3,4-Diacetoxy-1-butene, etc., Substituted vinyl acetates such as isopropenyl acetate, 1-methoxyvinyl acetate, vinylidene chloride, 1,4-diacetoxy-2-butene, vinylene carbonate, etc. Can be mentioned.

Examples of the post-modification method include a method of acetoacetic esterification, acetalization, urethanization, etherification, grafting, phosphoric acid esterification, and oxyalkyleneization of PVA.

The number average degree of polymerization of PVA is preferably 1,100 to 4,000, more preferably 1,200 to 2,600. When the degree of polymerization of PVA is in the above range, the mechanical strength and workability of the obtained film tend to be good. The saponification degree of PVA is preferably 95 to 100 mol%, more preferably 99 to 100 mol%. When the degree of saponification is in the above range, the moisture resistance of the obtained film tends to be good.

EVOH is usually obtained by saponifying a copolymer of 10 to 65 mol% of ethylene and vinyl ester, and vinyl acetate is a typical example of such vinyl ester, but other fatty acid vinyl. Esters (vinyl propionate, vinyl pivalate, etc.) can also be used.

The ethylene unit content of EVOH is preferably 10 to 65 mol%, more preferably 15 to 55 mol%, still more preferably 20 to 50 mol%. When the ethylene unit content is 10 mol% or more, the melt moldability tends to be improved, and when the ethylene unit content is 65 mol% or less, the gas barrier property tends to be good. The ethylene content of EVOH can be determined by a nuclear magnetic resonance (NMR) method.

The saponification degree of EVOH is preferably 90 mol% or more, more preferably 95 mol% or more, still more preferably 99 mol% or more. When the saponification degree is 90 mol% or more, the gas barrier property under high humidity tends to be good. On the other hand, the saponification degree of EVOH may be 100 mol% or less. When EVOH contains two or more different EVOH formulations, each ethylene unit content or saponification degree calculated from the compounding weight ratio is defined as the ethylene content or saponification degree of EVOH.

EVOH may have a unit derived from a monomer other than ethylene and vinyl ester and a saponified product thereof, as long as the object of the present invention is not impaired. When EVOH has the other monomer unit, the content of the other monomer unit with respect to the total structural unit of EVOH is preferably 30 mol% or less, more preferably 20 mol% or less, and 10 mol% or less. More preferably, 5 mol% or less is particularly preferable. When EVOH has a unit derived from the other monomer, the lower limit thereof may be 0.05 mol% or 0.10 mol%. Examples of the other monomer include alkenes such as propylene, butylene, penten, and hexene; 3-allyloxy-1-propene, 3-acyloxy-1-butene, 4-acyloxy-1-butene, 3,4- Diacyloxy-1-butene, 3-acyloxy-4-methyl-1-butene, 4-acyloxy-2-methyl-1-butene, 4-acyloxy-3-methyl-1-butene, 3,4-diasiloxy-2- Methyl-1-butene, 4-allyloxy-1-pentene, 5-acyloxy-1-pentene, 4,5-diasiloxy-1-pentene, 4-acyloxy-1-hexene, 5-acyloxy-1-hexene, 6- Alkenes having ester groups such as asyloxy-1-hexene, 5,6-diasiloxy-1-hexene, 1,3-diacetoxy-2-methylenepropane or saponified products thereof; acrylic acid, methacrylic acid, crotonic acid, itaconic acid, etc. Unsaturated acid or its anhydride, salt, mono or dialkyl ester, etc .; nitriles such as acrylonitrile and methacrylonitrile; amides such as acrylamide and methalkylamide; olefins such as vinyl sulfonic acid, allyl sulfonic acid and methallyl sulfonic acid. Sulphonic acid or a salt thereof; vinyl silane compounds such as vinyl trimethoxysilane, vinyl triethoxysilane, vinyl tri (β-methoxy-ethoxy) silane, γ-methacryloxypropyl methoxysilane; alkyl vinyl ethers, vinyl ketone, N-vinylpyrrolidone, vinyl chloride , Vinylidene chloride and the like.

The EVOH may be an EVOH post-modified by a method such as urethanization, acetalization, cyanoethylation, or oxyalkyleneization.

The melt flow rate (MFR) at 190 ° C. and a load of 2160 g, measured according to JIS K 7210: 2014 of EVOH, is preferably 0.5 g / 10 min or more, and more preferably 1.0 g / 10 min or more. On the other hand, the MFR of EVOH is preferably 20 g / 10 min or less, more preferably 10 g / 10 min or less, and even more preferably 5.0 g / 10 min or less. When the MFR of EVOH is in the above range, the melt moldability tends to be excellent.

The base material (X) is, for example, a resin other than a vinyl alcohol polymer, a carboxylic acid compound, a phosphoric acid compound, a boron compound, a metal salt, a stabilizer, and an antioxidant as long as the effect of the present invention is not impaired. , UV absorbers, antistatic agents, phosphoric acids, colorants, fillers, desiccants, reinforcing agents such as various fibers and the like. In particular, when EVOH is used as the vinyl alcohol-based polymer, it is preferable to contain a metal salt, a carboxylic acid compound, a phosphoric acid compound, a boron compound and the like from the viewpoint of thermal stability and viscosity adjustment.

A known film forming method for the base material (X) can be applied. For example, a casting method in which a solution of a vinyl alcohol polymer is cast on a metal surface such as a drum or an endless belt to form a film. Alternatively, the film is formed by a melt molding method in which melt extrusion is performed by an extruder.

An example of melt extrusion of the base material (X) will be described with reference to FIG. The extruder shown in FIG. 1 includes a die 60 for melt-extruding the vinyl alcohol polymer 100, a first transfer roll (casting roll) 70 for conveying the vinyl alcohol polymer 100 extruded from the die 60, and a second transfer roll. The 80 and the take-up machine 90 are provided with an air knife 110 arranged on the opposite side of the vinyl alcohol polymer 100 from the casting roll 70. Air A can be blown from the air knife 110 with any strength. The vinyl alcohol-based polymer 100 is melt-extruded by this extruder, and the film roll 101 of the vinyl alcohol-based polymer 100 is obtained by winding it around the take-up machine 90 while being conveyed by the casting roll 70 and the second transfer roll 80. ..

As the conditions for melt molding, any conditions can be used as long as the vinyl alcohol polymer can be melted. The take-up speed of the vinyl alcohol-based polymer 100 in the take-up machine 90 is preferably 20 m / min or more from the viewpoint of productivity. Further, the pick-up speed of the pick-up machine 90 is preferably 150 m / min or less, more preferably 120 m / min or less, from the viewpoint of controlling the surface roughness (Ra). When the take-up speed of the base material (X) is high, tension is applied before the molten resin is cured, and a large amount of air is contained between the cast roll and the base material (X), resulting in surface roughness (Ra). It tends to increase. In addition, these films may be stretched or heat-treated within the scope of exhibiting the effects of the present invention.

The average thickness of the base material (X) is not particularly limited, but from the viewpoint of industrial productivity, it is preferably 5 to 100 μm, more preferably 8 to 50 μm, and preferably 10 to 20 μm. Especially preferable.

The surface roughness of the base material (X) is obtained by subjecting the base material (X) to surface treatment such as UV ozone treatment, high-concentration ozone water treatment, excima ozone treatment, corona treatment, oxygen plasma treatment, or AP plasma treatment. Although (Ra) can be improved, it is preferable that the base material (X) is not surface-treated from the viewpoint of concern about ozone vapor deposition loss due to the oligomer generated by the surface treatment and the production cost.

[Layer (Y)]
The multilayer structure of the present invention tends to have excellent gas barrier properties and adhesion under harsh conditions because it contains an aluminum-deposited layer (Y). Here, the "aluminum-deposited layer" means a vapor-deposited layer containing aluminum as a main component, and the proportion of aluminum in the vapor-deposited layer is more than 50% by mass, preferably 70% by mass or more, and more preferably 90% by mass or more. It is more preferable that the vapor-deposited layer is made of substantially only aluminum. When aluminum oxide is inevitably generated during vapor deposition, aluminum oxide may be partially contained, but the amount of aluminum oxide inevitably contained affects the effect of the present invention. Does not give. It is preferable that the multilayer structure of the present invention is provided with layers (Y) on both sides of the base material (X) from the viewpoint of further enhancing the gas barrier property.

The lower limit of the average thickness of the layer (Y) is preferably 15 nm, more preferably 20 nm, and even more preferably 30 nm. The upper limit of the average thickness of the layer (Y) is preferably 150 nm, more preferably 130 nm, and even more preferably 100 nm. When the average thickness of the vapor-deposited layer is at least the above lower limit, the gas barrier property tends to be good. On the other hand, when the average thickness of the vapor-deposited layer is not more than the above upper limit, heat bridges are less likely to occur in the vacuum heat insulating body using the multilayer structure of the present invention, and the heat insulating performance tends to be good.

Examples of the layer (Y) forming method include a vacuum deposition method, a sputtering method, an ion plating method, and a chemical vapor deposition method (CVD). Above all, the vacuum vapor deposition method is preferable from the viewpoint of productivity. As the heating method for vacuum vapor deposition, any of an electron beam heating method, a resistance heating method and an induction heating method is preferable. Further, in order to improve the adhesion to the base material (X) on which the layer (Y) is formed, a plasma assist method or an ion beam assist method may be adopted for vapor deposition.

The upper limit of the surface temperature of the base film at the time of vapor deposition is preferably 60 ° C., more preferably 55 ° C., and even more preferably 50 ° C. The lower limit of the surface temperature of the base film at the time of vapor deposition is not particularly limited, but is preferably 0 ° C., more preferably 10 ° C., and even more preferably 20 ° C.

Since the layer (Y) is an aluminum-deposited layer, it has excellent light-shielding properties and metallic luster, and in food packaging materials and decorative films, it is possible to suppress deterioration of the contents or the base material due to ultraviolet transmission. can. On the other hand, in the vacuum heat insulating plate application, in addition to the above, by reflecting near infrared rays to infrared rays, it is possible to provide a multilayer structure having excellent heat insulating performance.

[Structure (XY)]
The multilayer structure of the present invention has a structure (XY) in which a layer (Y) is laminated on at least one surface of a base material (X). Here, "laminated" may mean that an adhesive layer is interposed between the base material (X) and the layer (Y), but from the viewpoint of improving adhesion under harsh conditions, the term "laminated" means that the base material (X) is used. It is preferable that the layer (Y) is directly laminated. The multilayer structure of the present invention has a structure (XY), and the surface roughness by an AFM (atomic force microscope) measured in accordance with JIS B0601: 2001 on the surface side of the aluminum vapor deposition layer (Y) of the structure (XY). When (Ra) is 3.0 nm or more and 50 nm or less, it tends to have high gas barrier property and adhesion, and also excellent adhesion under harsh conditions.

The surface roughness (Ra) measured by AFM (Atomic Force Microscope) on the surface side of the aluminum vapor deposition layer (Y) of the structure (XY) according to JIS B0601: 2001 has improved adhesion due to the increase in the boundary area and anchoring effect. From the viewpoint of improvement, it is 3.0 nm or more, preferably 5.5 nm or more, and more preferably 7.0 nm or more. The surface roughness (Ra) is 50 nm or less, preferably 30 nm or less, and more preferably 15 nm or less, from the viewpoint that the barrier property of the aluminum vapor deposition layer is not lowered due to the thin film deposition. The surface roughness (Ra) can be adjusted by, for example, the take-up speed after melt extrusion, the conditions of stretching and heat treatment, and the like. In particular, when the base material (X) is stretched, the crystal size tends to be reduced due to the orientation crystallization, and the surface roughness (Ra) tends to be reduced. Therefore, the base material (X) is preferably unstretched. Further, from the viewpoint of the strength of the film at the time of vapor deposition, when the base material (X) is unstretched, it is preferably micro-oriented in the MD direction, and such micro-orientation is formed by extrusion molding of the base material (X). It tends to be done.

The adhesion between the base material (X) and the layer (Y) of the structure (XY) under normal conditions can be evaluated by the T-type peel strength measured in accordance with JIS K6854-3: 1999, and is specific. As the method, the means as described in the examples can be applied. The T-type peel strength is preferably 300 gf / 15 mm or more, more preferably 400 gf / 15 mm or more, and even more preferably 500 gf / 15 mm or more. The T-type peel strength may be 10 kgf / 15 mm or less, or 5 kgf / 15 mm or less.

The adhesion between the base material (X) and the layer (Y) of the structure (XY) under severe conditions is the T-type peel strength measured in accordance with JIS K6854-3: 1999 while dropping water on the peel interface. As a specific method, the means as described in the examples can be applied. The T-type peel strength is preferably 250 gf / 15 mm or more, more preferably 350 gf / 15 mm or more, and even more preferably 400 gf / 15 mm or more. The T-type peel strength may be 10 kgf / 15 mm or less, or 5 kgf / 15 mm or less.

[Layer (Z)]
From the viewpoint of the protective properties of the layer (Y), the multilayer structure of the present invention may be abbreviated as a layer (Z) containing an organic polymer on one surface of the layer (Y) (hereinafter, abbreviated as "layer (Z)". ) May have a laminated structure. Here, "laminated" indicates that the layers may be laminated via an adhesive layer, but the layer (Z) and the layer (Y) may be laminated from the viewpoint of being more excellent in the protective characteristics of the layer (Y). Is preferably directly laminated.

The organic polymer contained in the layer (Z) preferably contains an organic polymer having at least one functional group selected from the group consisting of functional groups containing a hydroxyl group, a carboxylic acid group and a phosphorus atom. Further, the organic polymer may be a mixture of two or more kinds of organic polymers having different functional groups.

Examples of the organic polymer having a hydroxyl group include vinyl alcohol-based polymers exemplified as the material of the base material (X). Examples of the organic polymer having a carboxylic acid group include polyacrylic acid, polymethacrylic acid, or a copolymer of acrylic acid and methacrylic acid, and a part of the carboxyl group in these polymers is a salt. Polymers can be mentioned.

Examples of the functional group containing a phosphorus atom include a phosphoric acid group, a phosphite group, a phosphonic acid group, a phosphonic acid group, a phosphinic acid group, a phosphinic acid group, and a functional group derived from these (for example, a salt). , (Partial) ester compounds, halides (eg, chlorides), dehydrated products, etc. Among them, a phosphoric acid group and a phosphonic acid group are preferable, and a phosphonic acid group is more preferable. Examples of the polymer having a functional group containing a phosphorus atom include 6-[(2-phosphonoacetyl) oxy] hexyl acrylate, 2-phosphonooxyethyl methacrylate, phosphonomethyl methacrylate, and 11-phosphonoun methacrylate. Polymers of phosphono (meth) acrylic acid esters such as decyl and 1,1-diphosphonoethyl methacrylate; vinylphosphonic acid, 2-propen-1-phosphonic acid, 4-vinylbenzylphosphonic acid, 4-vinylphenylphosphonic acid and the like. Polymers of phosphonic acids; polymers of phosphinic acids such as vinylphosphinic acid and 4-vinylbenzylphosphinic acid; phosphorylated starch and the like. The polymer may be a homopolymer of a monomer having a functional group containing at least one phosphorus atom, or a copolymer of two or more kinds of monomers. Further, as the polymer, two or more kinds of polymers composed of a single monomer may be mixed and used. Among them, a polymer of phosphono (meth) acrylic acid esters and a polymer of vinyl phosphonic acids are preferable, and a polymer of vinyl phosphonic acids is more preferable. That is, as the polymer, poly (vinyl phosphonic acid) is preferable. The polymer can also be obtained by hydrolyzing a vinyl phosphonic acid derivative such as a vinyl phosphonic acid halide or a vinyl phosphonic acid ester alone or after copolymerization.

The layer (Z) may further contain a hydrolyzed condensate of at least one compound (L) containing a metal atom to which at least one group selected from a halogen atom and an alkoxy group is bonded. In some cases, the barrier property was improved by including the hydrolyzed condensate of the compound (L) in the layer (Z). Although the cause has not been clarified, it is considered that the presence of the compound (L) has an effect of improving the adhesion between the layer (Y) and the layer (Z).

[Compound (L)]
When the compound (L) is hydrolyzed, at least a part of the hydrolyzable characteristic groups of the compound (L) is replaced with a hydroxyl group. Further, the condensation of the hydrolyzate forms a hydrolyzed condensate, which is a compound in which metal atoms are bonded via oxygen. Here, in order for this hydrolysis condensation to occur, it is important that the compound (L) has a hydrolyzable characteristic group (functional group). If these groups are not bonded, the hydrolysis condensation reaction does not occur or becomes extremely slow, making it difficult to obtain the effects of the present invention. Although Si may be classified as a metalloid element, Si will be described as a metal in the present specification. Examples of the hydrolyzable characteristic group of the compound (L) include X ¹ of the formula (I) described later. The hydrolyzed condensate can be produced from a specific raw material using, for example, a method used in a known sol-gel method. The raw materials include compound (L), compound (L) partially hydrolyzed, compound (L) completely hydrolyzed, compound (L) partially hydrolyzed and condensed, and compound ( A compound in which L) is completely hydrolyzed and a part thereof is condensed, or a combination thereof can be used. These raw materials may be produced by a known method or commercially available ones may be used. Although not particularly limited, for example, a condensate obtained by hydrolyzing and condensing about 2 to 10 molecules can be used as a raw material.

Compound (L) is represented by the following general formula (I).
SiX ¹ _r R _(4-r) (I)
[In the above formula (I), X ₁ is any one selected from the group consisting of F, Cl, Br, I, R ₆ O-, R ₇ COO-, (R ₈ CO) ₂ CH-, and NO _3. Representing one, R ₅ , R ₆ , R ₇ , and R ₈ each independently represent any one group selected from the group consisting of an alkyl group, an aralkyl group, an aryl group, and an alkenyl group. Represents an integer of 1-4. When multiple X ₁ is present, it may be different to those of X ₁ may be the same as each other. If multiple R ₅ are present, they R ₅ may be different may be identical or different. ]
It is preferably at least one compound represented by.

Specific examples of the compound (L) include tetrachlorosilane, tetrabromosilane, tetramethoxysilane, tetraethoxysilane, methyltrimethoxysilane, ethyltrimethoxysilane, octyltrimethoxysilane, phenyltrimethoxysilane, vinyltrimethoxysilane, and the like. Included are vinyltriethoxysilane, chlorotrimethoxysilane, chlorotriethoxysilane, dichlorodimethoxysilane, dichlorodiethoxysilane, trichloromethoxysilane, trichloroethoxysilane, and vinyltrichlorosilane. Of these, tetramethoxysilane and tetraethoxysilane are preferable as the compound (L).

[Adhesive layer (H)]
In the multilayer structure of the present invention, it can be laminated with another member (for example, another layer such as a thermoplastic resin film layer or a paper layer) via an adhesive layer (H). The adhesive layer (H) made of an adhesive resin can be formed by applying a known adhesive to the surface of the base material (X), the layer (Y) or the layer (Z). As the adhesive, a two-component reaction type polyurethane adhesive in which a polyisocyanate component and a polyol component are mixed and reacted is preferable. Further, the adhesiveness may be further enhanced by adding a small amount of additive such as a known silane coupling agent to the anchor coating agent or the adhesive. Preferable examples of the silane coupling agent include a silane coupling agent having a reactive group such as an isocyanate group, an epoxy group, an amino group, a ureido group and a mercapto group. By strongly adhering the multilayer structure of the present invention and other members via the adhesive layer (H), a barrier property can be obtained when the vacuum packaging bag of the vacuum insulating body of the present invention is manufactured or processed. Deterioration of appearance can be suppressed more effectively.

By increasing the thickness of the adhesive layer (H), the strength of the multilayer structure of the present invention can be increased. However, if the adhesive layer (H) is made too thick, the appearance tends to deteriorate. The average thickness of the adhesive layer (H) is preferably in the range of 0.03 to 0.18 μm, more preferably in the range of 0.04 to 0.14 μm, and preferably in the range of 0.05 to 0.10 μm. It is particularly preferable to be in. By setting the average thickness of the adhesive layer (H) in this range, deterioration of barrier properties and appearance can be suppressed when manufacturing or processing the vacuum packaging bag used for the vacuum insulation body of the present invention. Further, the impact resistance of the vacuum insulation body of the present invention can be enhanced.

The multilayer structure of the present invention can be laminated with other members other than the multilayer structure (for example, other layers such as a thermoplastic resin film layer and a paper layer). Lamination is possible either directly or by adhering or forming through the adhesive layer (H). Specific configurations include those shown in a configuration example of a vacuum packaging bag described later.

According to the present invention, it is possible to obtain a multilayer structure satisfying the following performance.
(Performance 1) The oxygen permeability at 20 ° C. and 85% RH measured according to JIS K7126-2: 2006 is 1.5 cc / m ² · day · atm or less.

[Vacuum packaging bag]
The vacuum packaging bag is a packaging material used by reducing the pressure inside, and includes a film material (hereinafter, may be referred to as a "laminated body") as a partition wall separating the inside and the outside. The vacuum packaging bag of the present invention is a multilayer structure of the present invention composed of a base material (X), a layer (Y) or a base material (X), a layer (Y) and a layer (Z), and other than the multilayer structure. (For example, a thermoplastic resin film layer, another layer such as a paper layer, etc.). Further, the vacuum packaging bag may include a plurality of the multilayer structures. A vacuum packaging bag having such other members (such as other layers) can be manufactured by bonding or forming the other members (such as other layers) directly or through an adhesive layer. By providing the vacuum packaging bag with such other members (such as other layers), the characteristics of the vacuum packaging bag can be improved or new characteristics can be imparted. For example, the vacuum packaging bag of the present invention can be provided with heat-sealing properties, and the barrier properties and mechanical properties can be further improved.

In particular, by using a polyolefin layer (hereinafter, sometimes abbreviated as PO layer) as the surface layer of the vacuum packaging bag, the vacuum packaging bag can be provided with heat-sealing properties and the mechanical properties of the vacuum packaging bag can be improved. It is preferable because it can be used. From the viewpoint of further improving the heat sealability and mechanical properties, the polyolefin is preferably polypropylene or polyethylene. Further, in order to improve the mechanical properties of the vacuum packaging bag, at least one film selected from the group consisting of biaxially stretched polypropylene film, polyester film, polyamide film and polyvinyl alcohol-based film is laminated as another layer. Is preferable. From the viewpoint of improving mechanical properties, polyethylene terephthalate (PET) is preferable as the polyester, nylon-6 is preferable as the polyamide, and ethylene-vinyl alcohol copolymer is preferable as the polyvinyl alcohol-based film. An adhesive layer (H) may be provided between the layers, if necessary.

The vacuum packaging bag used for the vacuum insulation body of the present invention may have the following configuration from the outer layer to the inner layer of the vacuum insulation body, for example. In the following configuration, "/" means that two layers sandwiching "/" are directly laminated. Further, "//" indicates that the two layers sandwiching "//" are indirectly laminated via the adhesive layer (H).
(1) Layer (Y) / Base material (X) // PO layer,
(2) Polyester layer // Layer (Y) / Base material (X) // PO layer,
(3) Polyamide layer // layer (Y) / base material (X) // PO layer,
(4) PO layer // layer (Y) / base material (X) // PO layer,
(5) Layer (Y) / base material (X) / layer (Y) // PO layer,
(6) Polyester layer // layer (Y) / base material (X) / layer (Y) // PO layer,
(7) Polyamide layer // layer (Y) / base material (X) / layer (Y) // PO layer,
(8) PO layer // layer (Y) / base material (X) / layer (Y) // PO layer,
(9) Polyester layer / layer (Y) // base material (X) // PO layer,
(10) Polyamide layer // layer (Y) / base material (X) // PO layer,
(11) PO layer // layer (Y) / base material (X) // PO layer,
(12) Polyester layer / layer (Y) // layer (Y) / base material (X) // PO layer,
(13) Polyamide layer / layer (Y) // layer (Y) / base material (X) // PO layer,
(14) PO layer / layer (Y) // layer (Y) / base material (X) // PO layer,
(15) Polyester layer / layer (Y) // layer (Y) / base material (X) / layer (Y) // PO layer,
(16) Polyamide layer / layer (Y) // layer (Y) / base material (X) / layer (Y) // PO layer,
(17) PO layer / layer (Y) // layer (Y) / base material (X) / layer (Y) // PO layer,
(18) Polyamide layer // Polyester layer / Layer (Y) // Layer (Y) / Base material (X) // PO layer,
(19) PO layer // polyester layer / layer (Y) // layer (Y) / base material (X) // PO layer,
(20) Polyamide layer // Polyester layer / Layer (Y) // Layer (Y) / Base material (X) // PO layer,
(21) PO layer // polyester layer / layer (Y) // layer (Y) / base material (X) // PO layer,
(22) Layer (Z) / Layer (Y) / Base material (X) // PO layer,
(23) Polyester layer // layer (Z) / layer (Y) / base material (X) // PO layer,
(24) Polyamide layer // layer (Z) / layer (Y) / base material (X) // PO layer,
(25) PO layer // layer (Z) / layer (Y) / base material (X) // PO layer,
(26) Layer (Z) / Layer (Y) / Base material (X) / Layer (Y) / Layer (Z) // PO layer,
(27) Polyester layer // layer (Z) / layer (Y) / base material (X) / layer (Y) / layer (Z) // PO layer,
(28) Polyamide layer // layer (Z) / layer (Y) / base material (X) / layer (Y) / layer (Z) // PO layer,
(29) PO layer // layer (Z) / layer (Y) / base material (X) / layer (Y) / layer (Z) // PO layer,
(30) Polyester layer / layer (Z) / layer (Y) // base material (X) // PO layer,
(31) Polyamide layer / layer (Z) / layer (Y) // base material (X) // PO layer,
(32) PO layer / layer (Z) / layer (Y) // base material (X) // PO layer,
(33) Polyester layer / layer (Y) // layer (Z) / layer (Y) / base material (X) // PO layer,
(34) Polyamide layer / layer (Y) // layer (Z) / layer (Y) / base material (X) // PO layer,
(35) PO layer / layer (Y) // layer (Z) / layer (Y) / base material (X) // PO layer,
(36) Polyester layer / layer (Y) // layer (Z) / layer (Y) / base material (X) / layer (Y) // layer (Z) / PO layer,
(37) Polyamide layer / layer (Y) // layer (Z) / layer (Y) / base material (X) / layer (Y) / layer (Z) // PO layer,
(38) PO layer / layer (Y) // layer (Z) / layer (Y) / base material (X) / layer (Y) / layer (Z) // PO layer,
(39) Polyamide layer // Polyester layer / Layer (Y) // Layer (Z) / Layer (Y) / Base material (X) // PO layer,
(40) PO layer // polyester layer / layer (Y) // layer (Z) / layer (Y) / base material (X) // PO layer,
(41) Polyamide layer // Polyester layer / Layer (Y) // Layer (Z) / Layer (Y) / Base material (X) // PO layer,
(42) PO layer // polyester layer / layer (Y) // layer (Z) / layer (Y) / base material (X) // PO layer,

Among the configurations of the vacuum packaging bag illustrated above, it is preferable that at least one of the following requirements is satisfied.
(1) At least one layer of the base material (X) is located closer to the core material than at least one layer (Y).
(2) At least one layer (Y) is directly laminated on at least one layer of the base material (X).

[Core material]
The core material used in the vacuum heat insulating body of the present invention is not particularly limited as long as it has heat insulating properties. For example, examples of the core material include pearlite powder, silica powder, precipitated silica powder, silica soil, calcium silicate, glass wool, rock wool, and resin foams (for example, styrene foam and urethane foam). Further, as the core material, a hollow container made of a resin or an inorganic material, a honeycomb-shaped structure, or the like may be used. Further, if necessary, the core material may contain an adsorbent that adsorbs water vapor, gas, or the like.

[Vacuum insulation]
In the vacuum insulation body of the present invention, the space inside the vacuum packaging bag is in a vacuum state. The vacuum state here does not necessarily mean an absolute vacuum state, and indicates that the pressure in the space inside the vacuum packaging bag is sufficiently lower than the atmospheric pressure. The internal pressure is determined from the required performance, ease of manufacture, and the like, but is usually 2 kPa (about 15 Torr) or less in order to exhibit the heat insulating performance. In order to sufficiently exhibit the heat insulating effect of the vacuum heat insulating body of the present invention, the internal pressure of the vacuum packaging bag is preferably 200 Pa (about 1.5 Torr) or less, more preferably 20 Pa or less, and 2 Pa or less. It is more preferable to have. The lower limit of the pressure in the space inside the vacuum packaging bag is not limited, but the pressure may be in the range of 0.001 Pa to 2 KPa.

The vacuum insulator of the present invention is stored at 100 ° C. immediately after preparation, and the upper limit of the thermal conductivity one day after storage is preferably 3.0 mW / (m · K), preferably 2.5 mW / (m · K). ) Is more preferable. On the other hand, as the lower limit of the thermal conductivity one day after the storage, 1.0 mW / (m · K) is preferable, and 1.2 mW / (m · K) is more preferable. If the thermal conductivity exceeds the upper limit, the heat insulating performance of the vacuum heat insulating body may be insufficient. On the contrary, when the thermal conductivity is less than the above lower limit, the manufacturing cost of the vacuum heat insulating body may increase. Here, the "thermal conductivity" is a value measured in accordance with JIS-A1412-1 (1999).

The vacuum heat insulating body of the present invention can maintain the heat insulating performance for a long period of time. As for the heat insulating performance, it is preferable that the vacuum heat insulating body of the present invention is stored at 100 ° C. immediately after production, and the thermal conductivity 90 days after storage is 4.8 mW / (m · K) or less, preferably 4.5 mW. It is more preferably less than / (m · K). The thermal conductivity 90 days after storage may be 2.0 mW / (m · K) or more.

The vacuum insulation of the present invention can be manufactured by a commonly used method. A vacuum insulation body of any shape and size can be formed according to the purpose of use and the like. For example, the vacuum insulation body of the present invention can be produced by the following methods 1 to 3.
(Method 1) First, two multilayer structures having a heat seal layer arranged on at least one surface are prepared. The two multilayer structures are superposed so that each heat-sealing layer is on the inside, and any three sides are heat-sealed to prepare a vacuum packaging bag. Next, the inside of the vacuum packaging bag is filled with the core material. Next, the space inside the vacuum packaging bag is evacuated, and the last side is heat-sealed as it is. In this way, a vacuum insulation is obtained.
(Method 2) First, one multilayer structure is bent so that the heat seal layer is on the inside, and arbitrary two sides are heat-sealed to prepare a vacuum packaging bag. Next, the inside of the vacuum packaging bag is filled with the core material. Next, the space inside the vacuum packaging bag is evacuated, and the last side is heat-sealed as it is. In this way, a vacuum insulation is obtained.
(Method 3) First, the core material is sandwiched between two multilayer structures, or the core material is sandwiched by bending the multilayer structure. Next, the peripheral edge portion where the multilayer structures overlap is heat-sealed leaving the vacuum exhaust port, and a vacuum packaging bag in which the core material is arranged is produced. Next, the space inside the vacuum packaging bag is evacuated, and the vacuum exhaust port is heat-sealed as it is. In this way, a vacuum insulation is obtained.

[Use]
The vacuum insulation body of the present invention can be used for various purposes requiring cold insulation and heat insulation. In particular, the vacuum heat insulating body of the present invention is extremely unlikely to deteriorate over time in heat insulating performance even when used under high temperature and high humidity, so that it is possible to achieve a sufficient service life as a heat insulating material. Water heater tanks, hot water toilet tanks, vending machine tanks, fuel cell tanks, automobile tanks, food insulation bags, warm PET bottles and cans, washing machine drums, coffee It is also useful for all heat insulation applications that require heat insulation, such as tea servers and jar pots.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to the following Examples.

The materials used in Examples and Comparative Examples are shown.
EVOH1: Ethylene unit content 32 mol%, saponification degree 100 mol%, MFR 1.6 g / 10 min (190 ° C, 2160 g load)
EVOH2: Ethylene unit content 44 mol%, saponification degree 100 mol%, MFR 5.7 g / 10 min (190 ° C, 2160 g load)
PVA: Polyvinyl alcohol; manufactured by Kuraray Co., Ltd. "Kuraray Poval (trademark) 60-98 (trade name)"
PET12: Biaxially stretched polyethylene lethalate film; manufactured by Toray Industries, Inc., "Lumirror (trademark) P60" (trade name), average thickness 12 μm
PE50: Non-stretched linear high-density polyethylene film; manufactured by Idemitsu Unitech Co., Ltd., "Unilux (registered trademark) LS-760C, average thickness 50 μm"
OPA15: Biaxially stretched polyamide film; manufactured by Unitika Ltd., "Emblem (registered trademark) ON-BC", average thickness 15 μm
CPP60: Unstretched polypropylene film; "CP RXC-22" manufactured by Mitsui Chemicals Tohcello Co., Ltd., average thickness 60 μm

[Manufacturing Example 1]
The pellets of EVOH1 were melted at 240 ° C. and extruded from a die onto a casting roll to obtain a base material (X-1) which was an unstretched EVOH film having an average thickness of 15 μm at a take-up speed of 100 m / min.

[Manufacturing Example 2]
A pellet of EVOH1 was melted at 240 ° C., extruded from a die onto a casting roll, and at the same time, air was blown at a wind speed of 30 m / sec using an air knife. A base material (X-2), which is an unstretched EVOH film having an average thickness of 15 μm, was obtained.

[Manufacturing Example 3]
A base material (X-3), which is an unstretched EVOH film, was obtained by forming a film in the same manner as in Production Example 1 except that the average thickness of the film obtained by changing the discharge amount was 12 μm.

[Manufacturing Example 4]
A film was formed in the same manner as in Production Example 1 except that the pellets of EVOH2 were used to obtain a base material (X-4) which is an unstretched EVOH film having an average thickness of 15 μm.

[Manufacturing Example 5]
The pellets of EVOH1 were melted at 240 ° C. and extruded from a die onto a casting roll to prepare an unstretched EVOH film having an average thickness of 170 μm. The obtained unstretched film was brought into contact with warm water at 80 ° C. for 10 seconds, and the tenter type simultaneous biaxial stretching facility was used at 90 ° C. at 90 ° C. for 3.2 times in the vertical (MD) direction and 3.0 times in the horizontal (TD) direction. The film was further stretched and heat-treated in a tenter set at 170 ° C. for 5 seconds to obtain a base material (X'-1) which is a biaxially stretched EVOH film having a total width of 3.6 m and an average thickness of 15 μm.

[Manufacturing Example 6]
Film formation, stretching, and heat treatment were carried out in the same manner as in Production Example 5 except that the discharge amount was changed to obtain a base material (X'-2) which is a biaxially stretched EVOH film having an average thickness of 12 μm.

[Manufacturing Example 7]
Using a tumbler to make 0.03 parts by mass of synthetic silica (average particle size 2.7 μm measured by the “Silicia 310P” laser method manufactured by Fuji Silysia Chemical Ltd.) with respect to 100 parts by mass of EVOH1 pellets. A base material (X-5), which is a non-stretched EVOH film, was prepared in the same manner as in Production Example 1 except that it was dry-blended and then melted at 240 ° C.

[Manufacturing Example 8]
A film was formed in the same manner as in Production Example 1 except that the take-up speed was changed to 200 m / min to obtain a substrate (X'-3) which is an unstretched EVOH film having an average thickness of 15 μm.

<Evaluation method>
(1) Average Thickness of Layer (Y) and Layer (Z) The multilayer structure obtained in Examples and Comparative Examples was cut with a microtome to expose a cross section, and then the cross section was subjected to a scanning electron microscope (S. The average thickness of the layer (Y) and the layer (Z) was measured by measurement using a backscattered electron detector of "ZEISS ULTRA 55" manufactured by i-Ai Nanotechnology.

(2) Surface roughness (Ra)
The multilayer structures obtained in Examples and Comparative Examples were sampled (length 1 cm x width 1 cm) and used with an atomic force microscope device (environmental control type unit E-sweep manufactured by Hitachi High-Tech Science Co., Ltd.), and JIS B0601: 2001. Measured under the conditions of probe: SN-FF01 (material Si3N4), scanning mode: tapping mode, scanning range: 3 μm × 3 μm, number of pixels (X / Y): 512 × 256, scanning speed 1.0 Hz. Then, the surface roughness (Ra) (square average roughness) on the surface side of the layer (Y) of the multilayer structure was calculated.

(3) T-type peel strength between the base material (X) and the layer (Y) in the dry state and the wet state For dry laminating on the surface of the multilayer structure obtained in Examples and Comparative Examples on the layer (Y) side. An adhesive (Mitsui Chemicals Co., Ltd. "Takelac A-520" and "Takenate A-50" mixed at a mass ratio of 6/1 to prepare an ethyl acetate solution with a solid content concentration of 23% by mass) was used as a bar coater. After coating with and drying with hot air at 50 ° C. for 5 minutes to form an adhesive layer, about half of the adhesive layer is covered with a Teflon (registered trademark) sheet, and PET12 is laminated on the adhesive layer to 80 ° C. Laminated with a heated nip roll, cured at 40 ° C. for 72 hours, and the interface between the layer (Y) and PET12 was partially peeled off. A sample for measuring the layer structure of (registered trademark) sheet) PET12 was prepared. The obtained measurement sample was cut into strips of 100 mm × 15 mm, and the T-type peel strength under normal conditions (dry) and water content (wet) was measured. In the measurement in the water-containing state (wet), 0.5 mL of water was dropped on the peeling surface (interface) of PET12 and the layer (Y), and the T-type peeling strength was measured according to JIS K 6854-1: 1999. The measurement was performed 5 times and the average value was adopted. The measurement conditions were as follows. By visually confirming that the layer (Y) was attached to PET12, it was assumed that the peel strength between the base material (X) and the layer (Y) could be measured. Further, when the T-type peel strength is 500 gf / 15 mm or more in the dry state and 420 gf / 15 mm or more in the wet state, the adhesion of the layer (Y) to PET12 cannot be confirmed. It was set as the upper limit of measurement.
Equipment: Autograph AGS-H manufactured by Shimadzu Corporation
Peeling speed: 250 mm / min Temperature: 23 ° C
Humidity: 50% RH

(4) Measurement of Oxygen Permeability (OTR) The multilayer structure obtained in Examples and Comparative Examples was attached to an oxygen permeation measuring device so that the base material (X) faces the carrier gas side, and JIS K7126-2. : Oxygen permeability was measured by the isobaric method according to 2006. The measurement conditions were as follows.
Equipment: MOCON OX-TRAN2 / 21 manufactured by MOCON
Temperature: 20 ° C
Humidity on the oxygen supply side: 85% RH
Humidity on the carrier gas side: 0% RH
Carrier gas flow rate: 10 mL / min Oxygen pressure: 1.0 atm

(5) Thermal Conductivity of Vacuum Insulation Body The vacuum insulation obtained in Example 8 is stored at 100 ° C. immediately after production, and 1, 30 and 90 days after storage, a thermal conductivity measuring device (Eiko Seiki). Using FOX314 manufactured by FOX314 Co., Ltd.), the thermal conductivity of the vacuum insulator was measured by setting one side of the vacuum insulator to 38 ° C and the other surface side to 12 ° C.

[Example 1]
The base material (X-1) obtained in Production Example 1 was cut while being rewound to obtain a roll having a width of 80 cm and a length of 4000 m centered on the center position in the entire width of the film.

One of the base materials (X-1) is set to a surface temperature of 38 ° C. and a traveling speed of 200 m / min by using a batch type vapor deposition equipment (“EWA-105” manufactured by Nippon Vacuum Technology Co., Ltd.) for the base material (X-1). Aluminum was vapor-deposited on the surface of the substrate (X-1) to obtain a multilayer structure (1-1) having a layer structure of a base material (X-1) / layer (Y). With respect to the obtained multilayer structure (1-1), the average thickness of the layer (Y), the surface roughness (Ra) and the base material (X) were according to the methods described in the above evaluation methods (1) to (3). The T-type peel strength between the layer (Y) and the layer (Y) was evaluated. The results are shown in Table 2.

Using the obtained multilayer structure (1-1), a two-component adhesive ("Takelac A-520" and "Takenate A-50" manufactured by Mitsui Chemicals, Inc.) on one side of PET12 and PE50, respectively). Is applied, and laminated while pressure-bonding with a nip roll at 70 ° C. so as to have a composition of PET12 layer / adhesive layer / layer (Y) / base material (X-1) / adhesive layer / PE50 layer, and 4 at 40 ° C. By aging for days, a multilayer structure (1-2) was obtained. The OTR of the obtained multilayer structure (1-2) was evaluated according to the method described in the above evaluation method (4). The results are shown in Table 2.

[Examples 2 to 6, Comparative Examples 1 to 4]
As shown in Table 2, except that the type of the base material (X), the average thickness of the base material (X), the presence or absence of the layer (Y), and the average thickness of the layer (Y) are changed as shown in Table 1. Multi-layer structure (2-1) to multi-layer structure (6-1), multi-layer structure (C1-1) to multi-layer structure (C4-1), multi-layer structure (2-) in the same manner as in Example 1. 2) -Multi-layer structure (6-2) and multi-layer structure (C1-2) -multi-layer structure (C4-2) were prepared and evaluated. The results are shown in Table 2. In the multilayer structure C4-1 corresponding to Comparative Example 4, the thicknesses of the base material (X) and the layer (Y) were non-uniform, and a thin-film deposition defect was observed.

[Example 7]
The base material (X-1) obtained in Production Example 1 was cut while being rewound to obtain a roll having a width of 80 cm and a length of 4000 m centered on the center position in the entire width of the film.

One of the base materials (X-1) is set to a surface temperature of 38 ° C. and a traveling speed of 200 m / min by using a batch type vapor deposition equipment (“EWA-105” manufactured by Nippon Vacuum Technology Co., Ltd.) for the base material (X-1). Aluminum was vapor-deposited on the surface of the base material (X-1) to obtain a multi-layer structure having a layer structure of a base material (X-1) / layer (Y). A layer (Y') is formed on the surface of the obtained multilayer structure opposite to the layer (Y) in the same manner as the layer (Y), and the layer (Y) / base material (X-1) / layer ( A multilayer structure (7-1) of Y') was obtained. For the multilayer structure (7-1), the average thickness of the layer (Y), the surface roughness (Ra), the base material (X) and the layer ( The T-type peel strength with Y) was evaluated. The results are shown in Table 2.

Using the obtained multilayer structure (1-1), a two-component adhesive ("Takelac A-520" and "Takenate A-50" manufactured by Mitsui Chemicals, Inc.) on one side of PET12 and PE50, respectively). And crimping with a nip roll at 70 ° C. so that the composition is PET12 layer / adhesive layer / layer (Y) / base material (X-1) / layer (Y') / adhesive layer / PE50 layer. The multilayer structure (7-2) was obtained by laminating and aging at 40 ° C. for 4 days. The OTR of the obtained multilayer structure (7-2) was evaluated according to the method described in the above evaluation method (4). The results are shown in Table 2.

[Example 8]
The base material (X-1) obtained in Production Example 1 was cut while being rewound to obtain a roll having a width of 80 cm and a length of 4000 m centered on the center position in the entire width of the film.

One of the base materials (X-1) is set to a surface temperature of 38 ° C. and a traveling speed of 200 m / min by using a batch type vapor deposition equipment (“EWA-105” manufactured by Nippon Vacuum Technology Co., Ltd.) for the base material (X-1). Aluminum was vapor-deposited on the surface of the base material (X-1) to obtain a multi-layer structure having a layer structure of a base material (X-1) / layer (Y). The surface roughness (Ra) of the obtained multilayer structure was measured according to the method described in the above evaluation method (2). The results are shown in Table 2. Clarepovar ™ 60 on the layer (Y) of the obtained multilayer structure so that the solid content concentration is 5% by mass in a mixed solvent of water and methanol (water: methanol = 7: 3 by mass ratio). A coating solution in which −98 was dissolved was applied at a traveling speed of 200 m / min to obtain a multilayer structure (8-1) of a base material (X-1) / layer (Y) / layer (Z). With respect to the obtained multilayer structure (8-1), the average thickness of the layer (Y) and the base material (X) and the layer (Y) were determined according to the methods described in the above evaluation methods (1) and (3). The T-type peel strength was evaluated. The results are shown in Table 2.

Using the obtained multilayer structure (8-1), a two-component adhesive ("Takelac A-520" and "Takenate A-50" manufactured by Mitsui Chemicals, Inc.) on one side of PET12 and PE50, respectively). And laminate while pressure-bonding with a nip roll at 70 ° C. so that the composition is PET12 layer / adhesive layer / layer (Z) / layer (Y) / base material (X-1) / adhesive layer / PE50 layer. A multi-layer structure (8-2) was obtained by aging at 40 ° C. for 4 days. The OTR of the obtained multilayer structure (8-2) was evaluated according to the method described in the above evaluation method (4). The results are shown in Table 2.

[Example 8]
Using the multilayer structure (1-1) obtained in Example 1, a two-component adhesive (manufactured by Mitsui Chemicals, Inc., "Takelac A-520" and "Takenate A", respectively, on one side of OPA15 and CPP60. -50 ") is applied, and while crimping with a nip roll at 70 ° C., the composition is OPA15 layer / adhesive layer / layer (Y) / base material (X-1) / adhesive layer / CPP60 layer. The multilayer structure (8-2) was obtained by laminating and aging at 40 ° C. for 4 days.

The obtained multilayer structure (8-2) was cut to prepare two coating materials having a size of 20 cm × 25 cm, which were laminated so that the CPP layers were on the inner surface, and heat-sealed on three sides with a width of 10 mm. Then, a vacuum packaging bag, which is a three-way bag, was produced.

A heat insulating core material and a small bag containing calcium oxide as an adsorbent are filled from the opening of the obtained vacuum packaging bag, and the temperature is adjusted using a vacuum heat insulating panel manufacturing apparatus (KT-500RD type manufactured by NPC Co., Ltd.). A vacuum insulation was prepared by sealing the vacuum packaging bag at 20 ° C. and an internal pressure of 0.5 Pa. As the heat insulating core material, glass fiber dried in an atmosphere of 120 ° C. for 4 hours was used. The obtained vacuum heat insulating body was evaluated for thermal conductivity according to the method described in the above evaluation method (5). The results were 1.9 mW / (m · K) after 1 day, 2.0 mW / (m · K) after 30 days, and 2.3 mW / (m · K) after 90 days.

60 Extruder 70 1st Conveyance Roll (Casting Roll)
80 Second transport roll 90 Pick-up machine 100 Vinyl alcohol-based polymer 101 Vinyl alcohol-based polymer film roll 110 Air knife

Claims (11)

It has a structure (XY) in which an aluminum vapor deposition layer (Y) is laminated on at least one surface of a base material (X) made of a film containing a vinyl alcohol polymer as a main component, and the structure (XY) is aluminum vapor deposition. A multilayer structure having a surface roughness (Ra) of 3.0 nm or more and 50 nm or less by an AFM (atomic force microscope) measured according to JIS B0601: 2001 on the surface side of the layer (Y). The multilayer structure according to claim 1, wherein the vinyl alcohol-based polymer is an ethylene-vinyl alcohol copolymer having an ethylene unit content of 10 to 65 mol% and a saponification degree of 90 mol% or more. The multilayer structure according to claim 1 or 2, wherein the aluminum vapor deposition layer (Y) has an average thickness of 15 nm or more and 150 nm or less. The multilayer structure according to any one of claims 1 to 3, wherein the aluminum vapor deposition layer (Y) is laminated on both sides of a base material (X) made of a film containing a vinyl alcohol polymer as a main component. JIS K7126-2: 2006 was measured in accordance with, 20 ° C., the oxygen permeability at 85% RH is less than ^{1.5cc / m 2 · day · atm} , according to any one of claims 1 to 4 Multi-layer structure. T of a base material (X) made of a film containing a vinyl alcohol-based polymer as a main component and an aluminum-deposited layer (Y) measured in accordance with JIS K6854-3: 1999 while dropping water on the peeling interface. The multilayer structure according to any one of claims 1 to 5, wherein the mold peeling strength is 250 gf / 15 mm or more. The multilayer structure according to any one of claims 1 to 6, which has a structure in which a layer (Z) containing an organic polymer is laminated on one surface of an aluminum vapor-deposited layer (Y). The method for producing a multilayer structure according to any one of claims 1 to 7, wherein the surface temperature of the base material (X) made of a film containing a vinyl alcohol polymer as a main component is 60 ° C. or less. A method for manufacturing a multilayer structure, comprising a step of forming an aluminum vapor-deposited layer (Y). A packaging material comprising the multilayer structure according to any one of claims 1 to 7. A vacuum packaging bag in which the inside of the packaging material according to claim 9 is decompressed. The vacuum packaging bag according to claim 10 is a vacuum insulating body having a core material inside.

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