JP6891050B2 - Multi-layer structure, vacuum packaging bag and vacuum insulation - Google Patents

Description

The present invention relates to a multilayer structure having excellent barrier properties, a vacuum packaging bag containing the multilayer structure, and a vacuum insulating body using the vacuum packaging bag.

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. Vacuum insulation makes it possible to achieve insulation properties equivalent to those of urethane foam insulation with 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 improved gas barrier property and a gas barrier film used for the vacuum packaging bag have been proposed.

For example, in Patent Document 1, as a film used for a vacuum packaging bag having enhanced gas barrier properties, a vapor-deposited film is contained on one side of an ethylene-vinyl alcohol copolymer film, and an inorganic substance is contained in polyvinyl alcohol so as to be adjacent to the vapor-deposited film. A gas barrier film having a coated layer is described.

Further, as a coating material using a film having enhanced gas barrier properties, Patent Document 2 describes a coating material provided with a gas barrier layer containing a reaction product of a metal oxide and a phosphorus compound on one side of a polyvinyl alcohol-based resin film layer. Are listed. Further, Patent Document 3 describes a coating material in which a layer containing aluminum and a polymer having a phosphorus atom are laminated on one side of a stretched polyethylene terephthalate film.

Japanese Unexamined Patent Publication No. 2008-114520 Japanese Unexamined Patent Publication No. 2011-226644 Japanese Unexamined Patent Publication No. 2015-75182

However, the vacuum packaging bag using the conventional gas barrier film has a reduced gas barrier property when exposed to physical stress such as impact or bending, or under harsh conditions such as storage at high temperature or high humidity. In some cases. The main cause is considered to be damage to the barrier layer due to physical stress and dimensional changes of the base material under high temperature or high humidity environment storage. In the vacuum insulation body using such a vacuum packaging bag, the thermal conductivity is increased due to the decrease in the gas barrier property, and the stability of the low thermal conductivity may not be sufficient. Therefore, there is a demand for a vacuum packaging bag that maintains a high level of gas barrier properties even under harsh conditions, and a vacuum insulation body that has low thermal conductivity for a long period of time.

An object of the present invention is to use a vacuum packaging bag capable of maintaining a high level of the original barrier property even under physical stress and maintaining a high level of gas barrier property even during high temperature or high humidity storage. It is a provision of a vacuum insulating body which has been used, and a multilayer structure useful for the vacuum packaging bag.

According to the present invention, the above object is
[1] A multilayer structure including a base material (X), a vapor-deposited layer (Y) and a layer (Z), wherein the base material (X) is made of a polyvinyl alcohol-based resin film, and the vapor-deposited layer (Y) is formed. A polymer (A) containing mainly aluminum and having a plurality of phosphorus atoms in the layer (Z) is contained, and a thin-film deposition layer (Y) and a layer (Z) are formed on at least one surface of the base material (X). Multi-layer structure laminated in the order of material (X) / thin-film deposition layer (Y) / layer (Z);
[2] The multilayer structure of [1], wherein the base material (X) is a film made of 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 according to [1] or [2], wherein the polymer (A) having a plurality of phosphorus atoms is poly (vinyl phosphonic acid);
[4] The multilayer structure according to any one of [1] to [3], wherein the content of aluminum in the vapor-deposited layer (Y) is 60% by mass or more;
[5] Oxygen permeability under the conditions of 40 ° C. and 65% RH (carrier gas side) / 65% RH (oxygen supply side) after the gelboflex test is 0.5 ml / (m ² · day · atm) or less. The multilayer structure according to any one of [1] to [4];
[6] A vacuum packaging bag in which a film material is provided as a partition partition separating the inside and the outside and the inside is depressurized, and the film material contains a multilayer structure according to any one of [1] to [5]. Packaging bag;
[7] A vacuum insulating body provided with the vacuum packaging bag of [6] and a core material arranged inside surrounded by the vacuum packaging bag, and the inside of which is depressurized;
Is achieved by providing.

According to the present invention, a vacuum packaging bag capable of maintaining a high level of the original barrier property even when subjected to physical stress and maintaining a high level of gas barrier property even during high temperature or high humidity storage, and the vacuum packaging bag. A vacuum insulating body using a packaging bag and a multi-layer structure useful for the vacuum packaging bag can be provided.

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.

As used herein, the term "gas barrier property" means the ability to barrier gases other than water vapor, unless otherwise specified. Further, in this specification, when simply described as "barrier property", it means both gas barrier property and water vapor barrier property.

Further, in the present specification, "/" indicates that the two layers sandwiching the "/" are directly laminated or laminated via an adhesive, and it is preferable that the two layers are directly laminated. Further, "//" indicates that two layers sandwiching "//" are laminated via an adhesive.

[Multi-layer structure]
In the multilayer structure of the present invention, a base material (X) made of a polyvinyl alcohol-based resin film, a vapor-deposited layer (Y) mainly containing aluminum, and a layer (Z) containing a polymer (A) having a plurality of phosphorus atoms are formed. The base material (X) / vapor deposition layer (Y) / layer (Z) are laminated in this order. The base material (X), the vapor-deposited layer (Y), and the layer (Z) in the multilayer structure of the present invention may each have two or more layers.

[Base material (X)]
The multilayer structure of the present invention exhibits excellent gas barrier properties by having a base material (X) made of a polyvinyl alcohol-based resin film. Further, since the base material (X) is composed of a polyvinyl alcohol-based resin film, the affinity with the vapor-deposited layer (Y) described later is enhanced, and the bending resistance is improved. The polyvinyl alcohol-based resin may have a vinyl alcohol unit in which the vinyl ester unit is saponified. For example, both a polyvinyl alcohol (hereinafter, may be abbreviated as PVA) resin and ethylene-vinyl alcohol. Examples thereof include polymer (hereinafter, may be abbreviated as EVOH) resin.

As the PVA resin, for example, vinyl esters such as vinyl acetate, vinyl formate, vinyl propionate, vinyl valerate, vinyl caprate, vinyl laurate, vinyl stearate, vinyl pivalate and vinyl versatic acid are polymerized alone. Then, the saponified PVA resin can be mentioned. Further, the PVA resin in the present invention may be a copolymer-modified or post-modified modified PVA resin. The homopolymerization of the vinyl ester and the saponification of the vinyl ester homopolymer can be carried out by a known method. Further, the copolymerized PVA resin is produced, for example, by copolymerizing the above-mentioned vinyl ester with an unsaturated monomer copolymerizable with the vinyl ester and then saponifying the resin, and the amount of the modification is usually the same. It is less than 10 mol%.

Examples of the unsaturated monomer copolymerizable with the vinyl ester include olefins such as ethylene, propylene, isobutylene, α-octene, α-dodecene and α-octadecene; 3-butene-1-ol and 4-pentyne. Derivatives of hydroxy group-containing α-olefins such as -1-ol and 5-hexene-1-ol and their acylates; acrylic acid, methacrylic acid, crotonic acid, maleic acid, maleic anhydride, itaconic acid, undecylenoic acid and the like. Unsaturated acids, salts thereof, monoesters, or dialkyl esters; nitriles such as acrylonitrile and metaacrylonitrile; amides such as diacetoneacrylamide, acrylamide and methacrylicamide; olefins such as ethylenesulfonic acid, allylsulfonic acid and metaallylsulfonic acid. Sulphonic acid or a salt thereof; alkyl vinyl ether, dimethylallyl vinyl ketone, N-vinylpyrrolidone, vinyl chloride, vinyl ethylene carbonate, 2,2-dialkyl-4-vinyl-1,3-dioquinane, glycerin monoallyl ether, 3,4 Vinyl compounds such as −diacetoxy-1-butene; substituted vinyl acetates such as isopropenyl acetate and 1-methoxyvinyl acetate; vinylidene chloride, 1,4-diacetoxy-2-butene, vinylene carbonate and the like can be mentioned.

The modified PVA resin is obtained by post-modifying PVA by a method such as acetoacetate esterification, acetalization, urethanization, etherification, grafting, phosphate esterification, or oxyalkyleneization.

In the present invention, the degree of polymerization of the PVA resin is preferably 1100 or more, more preferably 1200 or more. The degree of polymerization of the PVA resin is preferably 4000 or less, more preferably 2600 or less. When the degree of polymerization of the PVA resin is 1100 or more, the mechanical strength of the obtained vacuum packaging bag becomes good, which is preferable. On the other hand, when the degree of polymerization is 4000 or less, the processability at the time of film formation and stretching becomes good, which is preferable. The saponification degree of the PVA resin is preferably 90 mol% or more, more preferably 95 mol% or more, and further preferably 99 mol% or more. Further, the saponification degree of the PVA resin may be 100 mol% or less or 99.9 mol% or less. When the saponification degree is within the above range, the water resistance is improved and the gas barrier property against humidity is improved, which is preferable. The degree of polymerization and the degree of saponification of the PVA resin can be measured according to the method described in JIS K 6726 (1994).

The EVOH resin is usually copolymerized with ethylene and an acid vinyl ester such as vinyl acetate, vinyl formate, vinyl propionate, vinyl valerate, vinyl caprate, vinyl laurate, vinyl stearate, vinyl pivalate and vinyl versatic acid. It is obtained by saponifying the polymer. The copolymer of ethylene and vinyl ester can be produced and saponified by a known method. The degree of saponification of the vinyl ester component of the EVOH resin is preferably 90 mol% or more, more preferably 95 mol% or more, still more preferably 99 mol% or more. By setting the saponification degree to 90 mol% or more, the gas barrier property can be enhanced. The saponification degree of the EVOH resin may be 100 mol% or less or 99.99 mol% or less. The degree of saponification of the EVOH resin is ^{measured by nuclear magnetic resonance (1} H-NMR) measurement, and the peak area of hydrogen atoms contained in the vinyl ester structure and the peak area of hydrogen atoms contained in the vinyl alcohol structure are measured. Desired.

The ethylene unit content of the EVOH resin is 10 mol% or more, more preferably 15 mol% or more, further preferably 20 mol% or more, and particularly preferably 25 mol% or more. The ethylene unit content of the EVOH resin is preferably 65 mol% or less, more preferably 55 mol% or less, still more preferably 50 mol% or less. When the ethylene unit content is 10 mol% or more, the gas barrier property or dimensional stability under high humidity can be kept good. On the other hand, when the ethylene unit content is 65 mol% or less, the gas barrier property can be enhanced. The ethylene unit content of the EVOH resin can be determined by the NMR method.

In the present invention, the EVOH resin may contain 0.0002 to 0.2 mol% of a vinylsilane compound as a copolymerization component in order to improve stability during heating and melting. Here, examples of the vinylsilane compound include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltri (β-methoxy-ethoxy) silane, and γ-methacryloxypropylmethoxysilane. Of these, vinyltrimethoxysilane and vinyltriethoxysilane are preferably used. Further, the unsaturated monomer copolymerizable with the vinyl ester described above can be copolymerized as long as the object of the present invention is not impaired.

When the EVOH resin is a mixture of two or more different types of EVOH, the ethylene unit content or the degree of saponification calculated from the compounding mass ratio is used as the ethylene unit content or the degree of saponification of the EVOH resin. And.

In the present invention, the EVOH resin is an acid such as carboxylic acid or phosphoric acid; a metal salt such as an alkali metal salt or an alkaline earth metal salt; a boronic acid or a salt thereof or a boronic acid from the viewpoint of thermal stability and viscosity adjustment. It preferably contains an additive such as a boron compound such as an ester.

As the base material (X), a film formed by using the above-mentioned polyvinyl alcohol-based resin is used. A known method can be applied to such a film forming method, for example, a casting method or extrusion method in which a solution of a polyvinyl alcohol-based resin is cast on a metal surface such as a drum or an endless belt to form a film. Examples thereof include a melt molding method in which melt extrusion is performed by a machine.

As the polyvinyl alcohol-based resin film, a biaxially stretched film is preferable from the viewpoint of dimensional stability and gas barrier property. The draw ratio is 2.5 times or more and 4.5 times or less in the vertical direction (MD direction) and 2 in the horizontal direction (TD direction) from the viewpoint of thickness uniformity, barrier property, mechanical properties and film formation property. .5 times or more and 4.5 times or less, and the surface stretching ratio is preferably in the range of 7 times or more and 15 times or less, 2.5 times or more and 3.5 times or less in the vertical direction, and 2.5 or more and 3.5 times in the horizontal direction. It is more preferable that the surface stretching ratio is 8 times or more and 12 times or less. Such a stretching treatment method can be carried out according to a known method such as simultaneous biaxial stretching and sequential biaxial stretching which are usually performed.

As the base material (X), a biaxially stretched PVA resin film, a biaxially stretched EVOH resin film and the like can be preferably used, and a biaxially stretched EVOH resin film is more preferable.

The thickness of the base material (X) is not particularly limited, but is preferably 5 μm or more, more preferably 8 μm or more, still more preferably 10 μm or more from the viewpoint of industrial productivity. The thickness of the base material (X) is preferably 100 μm or less, more preferably 50 μm or less, further preferably 40 μm or less, and particularly preferably 30 μm or less.

[Embedded layer (Y)]
The thin-film deposition layer (Y) contained in the multilayer structure of the present invention is a thin-film deposition layer mainly containing aluminum. When the vapor-deposited layer (Y) mainly contains aluminum, the affinity with the base material (X) and the layer (Z) described later is improved, and the bending resistance is improved. When the vapor-deposited layer (Y) mainly contains aluminum, it means that the vapor-deposited layer (Y) contains two or more kinds of components including aluminum, and the content of aluminum is the highest. In Y), the content of aluminum is 50% by mass or more.

The vapor-deposited layer (Y) may contain components other than aluminum as long as the effects of the present invention are not impaired. Examples of other components include metals other than aluminum such as magnesium, tin and silicon, or metalloids, and non-metals such as carbon and nitrogen.

The content of aluminum in the vapor-deposited layer (Y) is preferably 60% by mass or more, more preferably 70% by mass or more, further preferably 80% by mass or more, particularly preferably 90% by mass or more, and most preferably 95% by mass or more. The aluminum content in the vapor-deposited layer (Y) may be substantially 100% by mass. When the aluminum content is 60% by mass or more, the balance between gas barrier property, physical stress resistance and storage stability under harsh conditions is good, which is preferable.

The thin-film deposition layer (Y) is preferably a thin-film deposition layer mainly containing aluminum. On the other hand, oxidation inevitably occurs, and aluminum oxide may be partially contained. When the vapor deposition layer (Y) contains a part of aluminum oxide, the ratio (O _mol / Al _mol ) of the substance amount (O _{mol ) of oxygen atoms to the substance amount (Al mol) of aluminum atoms constituting the vapor deposition layer (Y).} ) Is preferably 0.5 or less, more preferably 0.3 or less, further preferably 0.1 or less, particularly preferably 0.08 or less, and most preferably 0.05 or less.

The preferred thickness of the thin-film deposition layer (Y) is in the range of 20 to 200 nm. Within this range, a thickness that improves the barrier property or mechanical property of the multilayer structure may be selected. If the thickness of the thin-film deposition layer (Y) is less than 20 nm, the reproducibility of the barrier property of the thin-film deposition layer against oxygen gas or water vapor tends to decrease, and if the thickness of the thin-film deposition layer (Y) exceeds 200 nm. , The base material (X) is damaged by the heat during vapor deposition, and the barrier property tends to decrease or the productivity tends to be impaired. The thickness of the thin-film deposition layer (Y) is more preferably in the range of 30 to 150 nm, and even more preferably in the range of 40 to 100 nm.

Generally, when the thickness of the vapor-deposited layer is 20 nm or more, the vapor-deposited layer (Y) mainly containing aluminum has low transparency and has a metallic luster, while the vapor-deposited layer mainly containing aluminum oxide has transparency. Since they have high metallic luster and do not have metallic luster, they can be visually distinguished from each other. Further, when the light transmittance is measured by the method described in Examples, the transmittance of the thin-film vapor deposition layer (Y) mainly containing aluminum is generally 10% or less, and the transmittance of the thin-film deposition layer mainly containing aluminum oxide is Generally, it is 70% or more.

As a method for forming the thin-film deposition layer (Y), a vacuum vapor deposition method is preferable. As the heating method for vacuum deposition, an electron beam heating method, a resistance heating method or an induction heating method is preferable. Further, in order to improve the adhesion to the base material on which the vapor deposition layer is formed and the denseness of the vapor deposition layer, the plasma assist method or the ion beam assist method may be adopted for vapor deposition.

[Layer (Z)]
The layer (Z) is a layer containing a polymer (A) having a plurality of phosphorus atoms. The polymer (A) having a plurality of phosphorus atoms is typically a polymer having a functional group containing a phosphorus atom. Such functional groups include, for example, 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, (part)). Examples thereof include ester compounds, halides (for example, chlorides), dehydrated products, etc., and the polymer may have one type of these functional groups alone or two or more types thereof. As the functional group containing a phosphorus atom, a phosphoric acid group and a phosphonic acid group are preferable, and a phosphonic acid group is more preferable. Polymers having a functional group containing a phosphorus atom include 6-[(2-phosphonoacetyl) oxy] hexyl acrylate, 2-phosphonooxyethyl methacrylate, phosphonomethyl methacrylate, 11-phosphonoundecyl methacrylate, 1, Phosphono (meth) acrylic acid esters such as 1-diphosphonoethyl methacrylate; vinyl phosphonic acids such as vinylphosphonic acid, 2-propen-1-phosphonic acid, 4-vinylbenzylphosphonic acid, 4-vinylphenylphosphonic acid; Examples thereof include homopolymers or copolymers of monomers having a functional group containing a phosphorus atom, phosphorylated starch and the like, such as vinyl phosphinic acids such as vinyl phosphinic acid and 4-vinylbenzyl phosphinic acid. Among them, polymers of phosphono (meth) acrylic acid esters and vinyl phosphonic acids are preferable, polymers of vinyl phosphonic acids are more preferable, and poly (vinyl phosphonic acid) is further preferable. Further, as the polymer (A), two or more kinds of polymers composed of a single monomer may be mixed and used. The polymer (A) 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 number average molecular weight of the polymer (A) is preferably 1000 to 100,000. When the number average molecular weight is in the above range, the bending resistance of the multilayer structure of the present invention can be improved, and it also contributes to the viscosity stability of the coating liquid (S) described later.

The layer (Z) may be composed of only the polymer (A) or may further contain other components. Other components include, for example, polyethylene glycol; polyvinyl alcohol, modified polyvinyl alcohol containing 1 to 50 mol% of α-olefin units having 4 or less carbon atoms, and polyvinyl alcohol-based polymers such as polyvinyl acetal (polyvinyl butyral, etc.); Polysaccharides such as cellulose and starch; (meth) acrylic acid-based polymers such as polyhydroxyethyl (meth) acrylate, poly (meth) acrylic acid, ethylene-acrylic acid copolymer; ethylene-maleic anhydride copolymer Examples thereof include a hydrolyzate, a hydrolyzate of a styrene-maleic anhydride copolymer, and a maleic acid-based polymer such as a hydrolyzate of an isobutylene-maleic anhydride copolymer.

The layer (Z) is preferably formed by applying a coating liquid (S) prepared by dissolving the polymer (A) and, if necessary, other components in a solvent on the vapor-deposited layer (Y) and drying the layer (Z). Can be formed.

The thickness of the layer (Z) per layer is preferably 0.003 μm or more from the viewpoint of improving the bending resistance of the multilayer structure of the present invention. On the other hand, if the thickness of the layer (Z) is 1.0 μm or more, the effect of improving the bending resistance reaches saturation. Therefore, the total thickness of the layer (Z) should be 1.0 μm or less from the viewpoint of economy. Is preferable. The thickness of the layer (Z) can be controlled by the concentration of the coating liquid (S) used for forming the layer (Z) or the coating method thereof.

[Coating liquid (S)]
The solvent used in the coating liquid (S) can be appropriately selected depending on the type of the polymer (A), but water, alcohols, or a mixed solvent thereof is preferable. Solvents include ethers such as tetrahydrofuran, dioxane, trioxane, dimethoxyethane; ketones such as acetone and methyl ethyl ketone; glycols such as ethylene glycol and propylene glycol; methyl cellosolve, ethyl cellosolve, etc., as long as they do not interfere with the dissolution of the polymer (A). Glycol derivatives such as n-butyl cellosolve; glycerin; acetonitrile; amides such as dimethylformamide; dimethylsulfoxide; sulfolane and the like may be further contained.

The solid content concentration of the polymer (A) in the coating liquid (S) is preferably in the range of 0.01 to 60% by mass, preferably 0.1 to 50%, from the viewpoint of storage stability and coatability of the coating liquid (S). The range of% by mass is more preferable, and the range of 0.2 to 40% by mass is further preferable.

From the viewpoint of storage stability of the coating liquid (S) and gas barrier properties of the multilayer structure, the pH of the coating liquid (S) is preferably in the range of 0.1 to 6.0, preferably in the range of 0.2 to 5.0. More preferably, the range of 0.5 to 4.0 is even more preferable. The pH of the coating liquid (S) can be adjusted by a known method such as adding an acidic compound or a basic compound.

[Adhesive layer (H)]
In the multilayer structure of the present invention, the vapor deposition layer (Y) is arranged between the base material (X) and the vapor deposition layer (Y) even if the vapor deposition layer (Y) is laminated so as to be in direct contact with the base material (X). The vapor deposition layer (Y) may be laminated on the base material (X) via the adhesive layer (H). The adhesiveness between the base material (X) and the vapor-deposited layer (Y) may be enhanced by passing through the adhesive layer (H). As the adhesive constituting the adhesive layer (H), 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 improved by adding a small amount of an additive such as a known silane coupling agent. 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 base material (X) and the vapor-deposited layer (Y) via the adhesive layer (H), a barrier property is provided when the vacuum packaging bag of the vacuum insulation body of the present invention is manufactured or processed. And the deterioration of the appearance can be suppressed more effectively.

When the adhesive layer (H) is arranged between the base material (X) and the thin-film deposition layer (Y), the thickness of the adhesive layer (H) is preferably in the range of 0.03 to 0.18 μm. By setting the thickness of the adhesive layer (H) within this range, deterioration of the barrier property and appearance can be more effectively suppressed during the production or processing of 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 thickness of the adhesive layer (H) is more preferably in the range of 0.04 to 0.14 μm, further preferably in the range of 0.05 to 0.10 μm.

The multilayer structure of the present invention including the base material (X), the vapor-deposited layer (Y), the layer (Z) or the base material (X), the vapor-deposited layer (Y), the layer (Z) and the adhesive layer (H) is the same. A laminated body can be formed by laminating directly or via an adhesive layer with other members other than the multilayer structure (for example, a thermoplastic resin film layer such as a polyolefin film; a paper layer; another layer such as an aluminum oxide vapor deposition layer). .. Specific configurations include those shown in a configuration example of a vacuum packaging bag described later.

[Manufacturing method of multilayer structure]
The method for producing the multilayer structure of the present invention is not particularly limited, and a known method can be applied. For example, a step (i) of forming a vapor-deposited layer (Y) mainly containing aluminum on one surface of a base material (X); a coating liquid (A) containing a polymer (A) on the vapor-deposited layer (Y). Examples thereof include a manufacturing method including a step of coating S) (iii); and a step of forming a layer (Z) (iii).

In the step (i), for example, a commercially available polyvinyl alcohol-based resin film is used as the base material (X), and one surface of the base material (X) mainly contains aluminum using a known vapor deposition apparatus. Examples thereof include a method of forming a thin-film deposition layer (Y).

In the step (ii), the coating liquid (S) containing the polymer (A) is coated on the vapor-deposited layer (Y) obtained in the step (i). The coating method of the coating liquid (S) is not particularly limited, and for example, a casting method, a dipping method, a roll coating method, a gravure coating method, a screen printing method, a reverse coating method, a spray coating method, a kiss coating method, a die coating method, and a meta. Known methods such as a ring bar coating method, a chamber doctor combined coating method, a curtain coating method, and a bar coating method can be adopted.

In the step (iii), the layer (Z) is formed on the thin-film deposition layer (Y) by removing the solvent in the coating liquid (S) coated on the thin-film deposition layer (Y). The method for removing the solvent from the coating liquid (S) after coating is not particularly limited, and for example, a known drying method can be applied. The drying temperature may be, for example, 80 to 180 ° C. or 90 to 150 ° C.

[Vacuum packaging bag]
The vacuum packaging bag of the present invention is a packaging bag used by reducing the pressure inside, and includes a film material containing the above-mentioned multilayer structure as a partition partition separating the inside and the outside. The vacuum packaging bag may include a plurality of the multilayer structures, and includes other members (thermoplastic resin film layer; paper layer; other layers such as an aluminum oxide vapor deposition layer, etc.) other than the multilayer structure. You may be. By providing the vacuum packaging bag with the other members, 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, it is preferable that the surface layer of the vacuum packaging bag is a polyolefin layer (hereinafter, may be abbreviated as PO layer) from the viewpoint of imparting heat sealability or improving mechanical properties. As the polyolefin constituting such a polyolefin layer, polypropylene or polyethylene is preferable. Further, when it is important to further improve the mechanical properties of the vacuum packaging bag, at least one selected from the group consisting of a biaxially stretched polypropylene film, a polyester film, a polyamide film and a polyvinyl alcohol-based resin film as another layer. It is preferable to stack the films. 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 resin is preferable as the polyvinyl alcohol-based resin.

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.
(1) Layer (Z) / thin-film deposition layer (Y) / base material (X) // PO layer,
(2) Polyester layer // layer (Z) / thin-film deposition layer (Y) / base material (X) // PO layer,
(3) Polyester layer // Base material (X) / Vapor deposition layer (Y) / Layer (Z) // PO layer,
(4) Polyamide layer // layer (Z) / thin-film deposition layer (Y) / base material (X) // PO layer,
(5) Polyamide layer // Base material (X) / Vapor deposition layer (Y) / Layer (Z) // PO layer,
(6) PO layer // layer (Z) / thin-film deposition layer (Y) / base material (X) // PO layer,
(7) Layer (Z) / thin-film deposition layer (Y) / base material (X) / thin-film deposition layer (Y) / layer (Z) // PO layer,
(8) Polyester layer // layer (Z) / thin-film deposition layer (Y) / base material (X) / thin-film deposition layer (Y) / layer (Z) // PO layer,
(9) Polyamide layer // layer (Z) / thin-film deposition layer (Y) / base material (X) / thin-film deposition layer (Y) / layer (Z) // PO layer,
(10) PO layer // layer (Z) / thin-film deposition layer (Y) / base material (X) / thin-film deposition layer (Y) / layer (Z) // PO layer,
(11) Polyester layer / thin-film deposition layer (Y) // layer (Z) / thin-film deposition layer (Y) / base material (X) // PO layer,
(12) Polyamide layer / thin-film deposition layer (Y) // layer (Z) / thin-film deposition layer (Y) / base material (X) // PO layer,
(13) PO layer / thin-film deposition layer (Y) // layer (Z) / thin-film deposition layer (Y) / base material (X) // PO layer,
(14) Polyamide layer / thin-film deposition layer (Y) // layer (Z) / thin-film deposition layer (Y) / base material (X) / thin-film deposition layer (Y) / layer (Z) // PO layer,
(15) PO layer / thin-film deposition layer (Y) // layer (Z) / thin-film deposition layer (Y) / base material (X) / thin-film deposition layer (Y) / layer (Z) // PO layer,
(16) Polyamide layer // Polyester layer / Thin-film deposition layer (Y) // Layer (Z) / Thin-film deposition layer (Y) / Base material (X) // PO layer,
(17) PO layer // polyester layer / thin-film deposition layer (Y) // layer (Z) / thin-film deposition layer (Y) / base material (X) // PO layer,
(18) Polyamide layer // Polyester layer / Aluminum oxide vapor deposition layer // Layer (Z) / Thin film deposition layer (Y) / Base material (X) // PO layer,
(19) PO layer // polyester layer / aluminum oxide vapor deposition layer // layer (Z) / vapor deposition layer (Y) / base material (X) // PO layer,
(20) Polyamide layer // Substrate (X) / Evaporated layer (Y) / Layer (Z) // Layer (Z) / Evaporated layer (Y) / Substrate (X) // PO layer,
(21) PO layer // base material (X) / thin-film deposition layer (Y) / layer (Z) // layer (Z) / thin-film deposition layer (Y) / base material (X) // PO layer.

[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 low thermal conductivity. For example, examples of the core material include pearlite powder, silica powder, precipitated silica powder, diatomaceous earth, 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 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]
The vacuum heat insulating body of the present invention includes the vacuum packaging bag and a core material arranged inside surrounded by the vacuum packaging bag, and the inside thereof is depressurized. 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 pressure of the space inside the vacuum packaging bag is determined from the required performance, ease of manufacture, etc., and is usually 2 kPa (about 15 Torr) or less, preferably 200 Pa or less, and 20 Pa or less from the viewpoint of exhibiting low heat conduction performance. The following is more preferable, and 2 Pa or less is further preferable. The pressure in the space inside the vacuum packaging bag may be 0.001 Pa or more.

The thermal conductivity immediately after the production of the vacuum heat insulating body is preferably 3.0 mW / (m · K) or less, and more preferably 2.5 mW / (m · K) or less. On the other hand, the thermal conductivity immediately after the production is preferably 1.0 mW / (m · K) or more, and more preferably 1.2 mW / (m · K) or more. If the thermal conductivity exceeds 3.0 mW / (m · K), the low thermal conductivity performance of the vacuum insulator may be insufficient. When the thermal conductivity is 1.0 mW / (m · K) or more, a vacuum heat insulating body having good low thermal conductivity can be obtained at a relatively low cost. Here, the "thermal conductivity" is a value measured in accordance with JIS A 1412-1 (1999).

The method for producing the vacuum insulation body of the present invention is not particularly limited, and a vacuum insulation body having an arbitrary shape and size can be produced according to the purpose of use and the like by, for example, the following methods 1 to 3 which are usually performed.
(Method 1) First, two quadrangular multilayer structures in which a layer having a heat-sealing property (for example, a polyolefin layer) is arranged on at least one surface are prepared. The two multilayer structures are superposed so that the layers having heat-sealing properties are on the inside, and any three sides are heat-sealed to prepare a packaging bag. Next, the inside of the packaging bag is filled with a core material. Next, the space inside the packaging bag is evacuated, and the last side is heat-sealed in that state to obtain a vacuum insulation body.
(Method 2) First, one multilayer structure is bent so that the layer having heat sealability is on the inside, and arbitrary two sides are heat-sealed to prepare a packaging bag. Next, the inside of the packaging bag is filled with a core material. Next, the space inside the packaging bag is evacuated, and the last side is heat-sealed in that state to obtain a vacuum insulation body.
(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 to produce a packaging bag in which the core material is arranged. Next, the space inside the packaging bag is evacuated, and the vacuum exhaust port is heat-sealed in that state to obtain a vacuum heat insulating body.

[Use]
The vacuum insulation body of the present invention can be used for various purposes requiring cold insulation or heat insulation. In particular, the vacuum heat insulating body is extremely unlikely to deteriorate over time in low thermal conductivity performance even when used at high temperature or high humidity, and has a sufficient service life as a heat insulating material. Hot water toilet tanks, vending machine tanks, fuel cell tanks, automobile tanks, food insulation bags, PET bottles or cans, washing machine drums, coffee, tea servers, etc. It is useful for all heat retention applications that require low thermal conductivity, such as jar pots.

Hereinafter, the present invention will be described in more detail with reference to Examples and the like, but the present invention is not limited to the following Examples. In addition, "/" described in an Example means that two layers sandwiching "/" are directly laminated, and "//" means that two layers sandwiching "//" are laminated via an adhesive. Indicates that it has been done.

[Materials used in Examples and Comparative Examples]
Base material (X)
"EVAL (registered trademark) EF-XL" (trade name) (manufactured by Kuraray Co., Ltd., biaxially stretched EVOH film, ethylene unit content 32 mol%, thickness 12 μm) (hereinafter referred to as "EF-XL") There is)
-"Lumirror (registered trademark) P60" (trade name) (manufactured by Toray Industries, Inc., biaxially stretched polyester film) (hereinafter sometimes referred to as "PET")
Coating liquid (S)
-"PVA-117H" (trade name) (manufactured by Kuraray Co., Ltd., polyvinyl alcohol resin, saponification degree of 98 mol% or more)
Laminated body- "Emblem (registered trademark) ONBC" (trade name) (manufactured by Unitika Ltd., stretched polyamide film, thickness 15 μm) (hereinafter sometimes referred to as "OPA")
-"CP RXC-18" (trade name) (manufactured by Mitsui Chemicals Tohcello Co., Ltd., unstretched polypropylene film, thickness 60 μm) (hereinafter sometimes referred to as "CPP")
-"VM-PET1510" (trade name) (manufactured by Toray Industries, Inc., aluminum-deposited biaxially stretched polyester film, thickness 12 μm) (hereinafter sometimes referred to as "VM-PET")

[Evaluation method]
(1) Measurement of thickness of thin-film deposition layer (Y) and layer (Z) The multilayer structure obtained in Examples and Comparative Examples is cut with a focused ion beam (FIB), and a section for cross-section observation (thickness 0.3 μm). ) Was produced. The prepared section was fixed to a sample pedestal with carbon tape, and platinum ion sputtering was performed at an acceleration voltage of 30 kV for 30 seconds. The cross section of the multilayer structure was observed with a field emission transmission electron microscope [device: JEM-2100F manufactured by JEOL Ltd.], and the thickness of each layer was calculated. The measurement conditions were an acceleration voltage of 200 kV and a magnification of 250,000 times.

(2) Oxygen permeability The oxygen permeability of the laminate made of "OPA // multilayer structure // CPP" obtained in Examples and Comparative Examples is determined by the oxygen permeability measuring device (MOCON's "OX-TRAN 2"). / 20 ") was used for measurement. Specifically, the multilayer structure is set so that the layer (deposited layer (Y) or layer (Z)) faces the oxygen supply side and the base material (X) faces the carrier gas side, and the temperature is 40 ° C., oxygen. ^{Oxygen permeability (unit: ml / (m 2} · day · atm)) under the conditions that the humidity on the supply side is 65% RH, the humidity on the carrier gas side is 65% RH, the oxygen pressure is 1 atm, and the carrier gas pressure is 1 atm. Was measured. As the carrier gas, nitrogen gas containing 2% by volume of hydrogen gas was used.

(3) Oxygen permeability after the gelboflex test Regarding the gas barrier property when the laminate made of "OPA // multilayer structure // CPP" obtained in Examples and Comparative Examples receives physical stress Oxygen permeability before and after the Gelboflex test for flexibility was measured and evaluated. Specifically, the prepared laminate was cut into 210 mm × 297 mm, and the humidity was adjusted to 23 ° C. and 50% RH. Using a humidity-controlled film, make a cylinder with a diameter of 3.5 inches under the same atmosphere, fix both ends to a gelboflex tester (manufactured by Rigaku Kogyo Co., Ltd.), initial interval 7 inches, maximum bending With an interval of 1 inch, the first 3.5 inches of the stroke was twisted at an angle of 440 degrees, and the subsequent 2.5 inches were made three reciprocating reciprocating movements, which were linear horizontal movements. The oxygen permeability was measured using an oxygen permeation measuring device (“OX-TRAN2 / 20” manufactured by MOCON). Specifically, the multilayer structure is set so that the layer (deposited layer (Y) or layer (Z)) faces the oxygen supply side and the base material (X) faces the carrier gas side, and the temperature is 40 ° C. ^{Oxygen permeability (unit: ml / (m 2} · day · atm)) under the conditions that the humidity on the oxygen supply side is 65% RH, the humidity on the carrier gas side is 65% RH, the oxygen pressure is 1 atm, and the carrier gas pressure is 1 atm. ) Was measured. As the carrier gas, nitrogen gas containing 2% by volume of hydrogen gas was used.

(4) Thermal conductivity of vacuum insulation The vacuum insulation obtained in Examples and Comparative Examples is placed in a cardboard box (67 cm x 61 cm x 45 cm), loaded on a truck, and reciprocated 10 times between Okayama Prefecture and Tokyo. A transport test was conducted. After the vacuum insulation after the transportation test is stored at 100 ° C., 0% RH or 40 ° C., 90% RH for a certain period of time, vacuum insulation is performed using a thermal conductivity measuring device (FOX314 type manufactured by Eiko Seiki Co., Ltd.). The thermal conductivity (mW / (m · k)) of the vacuum adiabatic body was measured with one side of the body at 38 ° C. and the other side at 12 ° C. The measurement was performed 1, 30, and 90 days after the transportation test was carried out.

(5) Measurement of Light Transmittance The light transmittance of the multilayer structure at 500 nm was determined using an ultraviolet-visible spectrophotometer (“UV-2450” manufactured by Shimadzu Corporation).

[Manufacturing method of coating liquid (S-1)]
Under a nitrogen atmosphere, 10 g of vinyl phosphonic acid and 0.025 g of 2,2'-azobis (2-amidinopropane) dihydrochloride were dissolved in 5 g of water and stirred at 80 ° C. for 3 hours. The obtained polymer solution was cooled, diluted by adding 15 g of water, and filtered using a cellulose membrane (“Spectra / Por” (registered trademark) manufactured by Spectrum Laboratories). After distilling off the water in the filtrate, it was vacuum dried at 50 ° C. for 24 hours to obtain poly (vinyl phosphonic acid) (hereinafter sometimes referred to as "VPA homopolymer"). As a result of GPC analysis, the number average molecular weight of the obtained VPA homopolymer was 10,000 in terms of polyethylene glycol. Distilled water was added to the polymer, and the mixture was stirred for 1 hour or more while heating at 90 ° C. to obtain a 10.2 wt% aqueous solution. Further, 60.5 parts by mass of distilled water and 29.7 parts by mass of methanol were added to 9.8 parts by mass of the obtained aqueous solution and mixed so as to be uniform to obtain a coating liquid (S-1).

[Manufacturing method of coating liquid (S-2)]
Under a nitrogen atmosphere, 8.5 g of 2-phosphonooxyethyl methacrylate and 0.1 g of 2,2'-azobis (isobutyronitrile) were dissolved in 17 g of methyl ethyl ketone and stirred at 80 ° C. for 12 hours. After cooling the obtained solution, 170 g of 1,2-dichloroethane was added, and the precipitate was recovered by decantation. Subsequently, the precipitate was dissolved in tetrahydrofuran, purified by reprecipitation using 1,2-dichloroethane as a poor solvent three times, and then vacuum dried at 50 ° C. for 24 hours to obtain 2-phosphonooxyethyl methacrylate. (Hereinafter, it may be referred to as “PHM homopolymer”) was obtained. As a result of GPC analysis, the number average molecular weight of the obtained PHM homopolymer was 10,000 in terms of polystyrene. Distilled water was added to the polymer, and the mixture was stirred for 1 hour or more while heating at 90 ° C. to obtain a 10.2 wt% aqueous solution. Further, 60.5 parts by mass of distilled water and 29.7 parts by mass of methanol were added to 9.8 parts by mass of the obtained aqueous solution and mixed so as to be uniform to obtain a coating liquid (S-2).

[Manufacturing method of coating liquid (S-3)]
68.4 parts by mass of tetramethoxysilane (TMS) was dissolved in 82.0 parts by mass of methanol, and then 13.6 parts by mass of γ-glycidoxypropyltrimethoxysilane was dissolved, followed by 5.13 parts by mass of distilled water. And 12.7 parts by mass of 0.1N (0.1N) hydrochloric acid were added to prepare a sol, which was stirred and subjected to a hydrolysis and condensation reaction at 10 ° C. for 1 hour. After diluting the obtained sol with 185 parts by mass of distilled water, it is rapidly added to 634 parts by mass of a 10% by mass aqueous solution of polyvinyl alcohol resin (manufactured by Kuraray Co., Ltd., "PVA-117H" (trade name)) to provide a coating solution. (S-3) was obtained.

[Example 1]
A biaxially stretched EVOH film (“EVAL EF-XL” (trade name) manufactured by Kuraray Co., Ltd., ethylene unit content 32 mol%, thickness 12 μm) was prepared as a base material (X). Aluminum is melted and evaporated using a batch type vapor deposition apparatus (“EWA-105” manufactured by ULVAC Co., Ltd.), and a 40 nm thick vapor deposition layer (Y) mainly containing aluminum is formed on one surface of the base material (X). It was formed. Next, the coating liquid (S-1) was coated on the thin-film deposition layer (Y) with a bar coater so that the thickness after drying was 0.01 μm, and then dried at 110 ° C. for 3 minutes to obtain the thin-film deposition layer (Y). A layer (Z) was formed on Y), and a multilayer structure in which a base material (X) / a vapor-deposited layer (Y) / a layer (Z) was laminated in this order was produced. That is, a two-component adhesive (Mitsui Chemicals Co., Ltd. "Takelac (registered trademark) A520" (trade name), the company's "Takenate (registered trademark) A50" (trade name) and ethyl acetate on one side of OPA and CPP, respectively. Is applied in a mass ratio of 6: 1: 9.3) so that the dry film thickness is 4 μm, so that the composition is OPA layer / adhesive layer / multilayer structure / adhesive layer / CPP layer. CPP, OPA and the multilayer structure were laminated to obtain a laminated body composed of "OPA // multilayer structure // CPP". The multilayer structure was laminated so that the side having the vapor deposition layer (Y) and the layer (Z) was adjacent to the adhesive layer adjacent to OPA. The evaluations (1) to (3) above were carried out using the obtained multilayer structure and laminated body. Further, when the light transmittance of the multilayer structure was measured by the method (5) above, the transmittance was 10% or less, and the multilayer structure was visually confirmed to be opaque and had a metallic luster.

[Examples 2 to 5, Comparative Examples 1 to 3]
For the base material (X), the vapor-deposited layer (Y) and the layer (Z), a multilayer structure and a laminated body were prepared in the same manner as in Example 1 except that the materials shown in Table 1 were used, and Example 1 The evaluation was performed in the same manner as in.

[Comparative Example 4]
Comparison except that a 40 nm-thick thin-film vapor deposition layer (Y) mainly containing aluminum oxide was formed on one surface of the base material (X) by melting and evaporating aluminum while introducing oxygen as the thin-film deposition layer (Y). A multilayer structure and a laminated body were prepared in the same manner as in Example 3, and the above evaluations (1) to (3) were performed. Further, when the light transmittance of the multilayer structure was measured by the method (5) above, the transmittance was 70% or more, and the visual confirmation of the multilayer structure showed that it was transparent and did not have metallic luster. ..

[Comparative Example 5]
By melting and evaporating aluminum while introducing oxygen as the vapor deposition layer (Y), it is carried out except that a 40 nm thick vapor deposition layer (Y) mainly containing aluminum oxide is formed on one surface of the base material (X). A multilayer structure and a laminated body were prepared in the same manner as in Example 1, and the above evaluations (1) to (3) were performed. Further, when the light transmittance of the multilayer structure was measured by the method (5) above, the transmittance was 70% or more, and the visual confirmation of the multilayer structure showed that it was transparent and did not have metallic luster. ..

[Comparative Example 6]
A multilayer structure and a laminated body were prepared in the same manner as in Example 1 except that the vapor deposition layer (Y) was prepared by the method shown below, and the evaluation was carried out in the same manner as in Example 1. That is, 230 parts by mass of distilled water was heated to 70 ° C. with stirring, 88 parts by mass of aluminum isopropoxide was added dropwise over 1 hour, the liquid temperature was gradually raised to 95 ° C., and the generated isopropanol was distilled off. Hydrolysis condensation was carried out while allowing the mixture to grow. 4.0 parts by mass of a 60% by mass nitric acid aqueous solution was added to the obtained reaction solution, and the mixture was stirred at 95 ° C. for 3 hours to deflocculate the aggregates of the particles of the hydrolyzed condensate, and then the solid content concentration was oxidized. It was concentrated to 10% by mass in terms of aluminum. In addition to 18.66 parts by mass of the obtained dispersion, 58.19 parts by mass of distilled water, 19.00 parts by mass of methanol, and 5 parts by mass of polyvinyl alcohol resin (manufactured by Kuraray Co., Ltd., "PVA-117H" (trade name)). 0.50 parts by mass of% aqueous solution was added, and the mixture was uniformly stirred to obtain a dispersion. Subsequently, 3.66 parts by mass of an 85% by mass phosphoric acid aqueous solution was added dropwise while stirring the dispersion while maintaining the liquid temperature at 15 ° C., and the mixture was stirred at 15 ° C. until the viscosity reached 1,500 mPa · s. Subsequently, a coating liquid (L) was obtained. The molar ratio of aluminum atom to phosphorus atom in the coating liquid (L) was aluminum atom: phosphorus atom = 1.15: 1.00. The coating liquid (L) is coated on the base material (X) with a bar coater so that the thickness after drying becomes 0.3 μm, and then dried at 160 ° C. for 1 minute to react aluminum oxide with phosphoric acid. A layer of product was made on the substrate (X).

The evaluation results of Examples 1 to 5 and Comparative Examples 1 to 6 are shown in Table 1.

[Example 6]
The laminate obtained in Example 1 was cut to obtain two covering materials having a size of 50 cm × 50 cm. The two laminated bodies were laminated so that the CPP layers were on the inner surface, and heat-sealed on three sides with a width of 10 mm to prepare a packaging bag which is a three-sided bag. A core material having low thermal conductivity and a small bag containing calcium oxide as an adsorbent are filled from the opening of the obtained packaging bag, and a vacuum insulation panel manufacturing device (manufactured by NPC Co., Ltd., KT-500RD type) is used. The packaging bag was sealed at a temperature of 20 ° C. and an internal pressure of 1.0 Pa to prepare a vacuum insulator. As the core material having low thermal conductivity, glass fiber dried in an atmosphere of 160 ° C. for 4 hours was used. The obtained vacuum insulation was evaluated at 100 ° C. and 0% RH according to the method (4) above. The results are shown in Table 2.

[Examples 7 to 10 and Comparative Examples 7 to 12]
Using the laminates obtained in Examples 2 to 5 and Comparative Examples 1 to 6, a vacuum heat insulating body was prepared in the same manner as in Example 6, and evaluation was carried out in the same manner as in Example 6. The results are shown in Table 2.

[Example 11]
Using the multilayer structure obtained in Example 1, a laminate made of "OPA // VM-PET // multilayer structure // CPP" was prepared by the following method. A two-component adhesive (manufactured by Mitsui Chemicals Co., Ltd., "Takelac (registered trademark)" on one side of CPP and OPA, and on the aluminum vapor deposition layer side of the biaxially stretched polyester film (VM-PET) on which the aluminum vapor deposition layer is formed. ) A-520 ”and“ Takenate (registered trademark) A-50 ”) are applied to form an OPA layer / adhesive layer / VM-PET layer / adhesive layer / multilayer structure / adhesive layer / CPP layer. A laminated body was obtained by laminating CPP, OPA, VM-PET and a multilayer structure. In addition, VM-PET was laminated with the side having the aluminum vapor deposition layer as the multilayer structure side. Further, the multilayer structure was laminated so that the base material (X) side was adjacent to the CPP layer via the adhesive layer. The obtained laminated body was cut to obtain two covering materials having a size of 50 cm × 50 cm. The two laminated bodies were laminated so that the CPP layers were on the inner surface, and heat-sealed on three sides with a width of 10 mm to prepare a packaging bag which is a three-sided bag. A low thermal conductivity core material and a small bag containing calcium oxide as an adsorbent are filled from the opening of the obtained packaging bag, and a vacuum heat insulating panel sealing device (manufactured by NPC Co., Ltd., KT-500RD type) is used. The packaging bag was sealed at a temperature of 20 ° C. and an internal pressure of 1.0 Pa to prepare a vacuum insulator. As the core material having low thermal conductivity, glass fiber dried in an atmosphere of 160 ° C. for 4 hours was used. The obtained vacuum insulation was evaluated at 40 ° C. and 90% RH according to the method (4) above. The results are shown in Table 3.

[Examples 12 to 15 and Comparative Examples 13 to 18]
Using the multilayer structures obtained in Examples 2 to 5 and Comparative Examples 1 to 6, a vacuum heat insulating body was produced in the same manner as in Example 11, and evaluation was carried out in the same manner as in Example 11. The results are shown in Table 3.

The vacuum insulation bodies obtained in Examples 6 to 15 have a smaller change in thermal conductivity with time as compared with the vacuum insulation bodies obtained in Comparative Examples 7 to 18, and are stored for a long period of time under high temperature or high humidity. Under harsh conditions such as, it was excellent in stability with low thermal conductivity. Furthermore, as shown in Table 1, from the results of Examples 1 to 5, the vacuum packaging bag and the multilayer structure of the present invention maintain a high level of the original barrier property even when subjected to physical stress. it can.

The multilayer structure of the present invention and the vacuum packaging bag containing the multilayer structure can maintain a high level of barrier property even when subjected to physical stress. Further, a vacuum heat insulating body capable of maintaining excellent low thermal conductivity for a long period of time can be obtained even under harsh conditions such as storage at high temperature or high humidity.

Claims (6)

A multilayer structure including a base material (X), a thin-film deposition layer (Y), and a layer (Z).
The base material (X) is made of a polyvinyl alcohol-based resin film.
The vapor-deposited layer (Y) mainly contains aluminum and contains
The layer (Z) contains a polymer (A) having a plurality of phosphorus atoms, and the layer (Z) contains a polymer (A).
The polyvinyl alcohol-based resin film is a film made of an ethylene-vinyl alcohol copolymer having an ethylene unit content of 10 to 65 mol% and a saponification degree of 90 mol% or more.
A multilayer structure in which a thin-film deposition layer (Y) and a layer (Z) are laminated in the order of a base material (X) / a vapor-deposited layer (Y) / a layer (Z) on at least one surface of the base material (X). The multilayer structure according to claim 1 , wherein the polymer (A) having a plurality of phosphorus atoms is poly (vinyl phosphonic acid). The multilayer structure according to claim 1 or 2 , wherein the content of aluminum in the vapor-deposited layer (Y) is 70% by mass or more. The oxygen permeability under the conditions of 40 ° C. and 65% RH (carrier gas side) / 65% RH (oxygen supply side) after the gelboflex test is 0.5 ml / (m ² · day · atm) or less. The multilayer structure according to any one of claims 1 to 3. A vacuum packaging bag in which a film material is provided as a partition partition separating the inside and the outside and the inside is depressurized, and the film material includes the multilayer structure according to any one of claims 1 to 4. bag. A vacuum insulating body comprising the vacuum packaging bag according to claim 5 and a core material arranged inside surrounded by the vacuum packaging bag, the inside of which is depressurized.