JP6788576B2 - Multi-layer structure, vacuum packaging bag and vacuum insulation - Google Patents

Description

The present invention includes a multilayer structure having excellent barrier properties, a vacuum packaging bag containing the multilayer structure, and a core material arranged inside the vacuum packaging bag and the vacuum packaging bag. It relates to a vacuum insulation body whose inside is depressurized.

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 makes it possible to achieve the same insulation properties as the insulation properties of the urethane foam insulation 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.

One of the characteristics required for a vacuum packaging bag of a vacuum insulation body is barrier property. Therefore, a vacuum packaging bag with improved barrier properties has been proposed.

As a film used for a vacuum packaging bag having enhanced barrier properties, Patent Document 1 describes a thin-film film on one side of a polyethylene vinyl alcohol copolymer film and a coating of polyvinyl alcohol containing an inorganic substance so as to be adjacent to the thin-film film. A film having a layer is described, and Patent Document 2 describes an intermediate film formed by applying a thin-film vapor-deposited thin film layer and a coating agent containing a water-soluble polymer on one side of a base material made of a plastic material and heating and drying the film. A laminated body in which a layer and a thin-film vapor-deposited thin film layer are sequentially laminated is described. Patent Document 3 describes a gas barrier laminate including a base material and a gas barrier layer laminated on at least one surface of the base material, wherein the gas barrier layer is a functional group selected from a carboxyl group and a carboxylic acid anhydride group. Described is a gas barrier laminate comprising a composition containing a polymer containing the functional group, wherein at least a part of the -COO- group contained in the functional group is neutralized with a metal ion having a valence of 2 or more. Further, Patent Document 4 describes a multilayer structure in which a layer containing an aluminum atom and a layer containing a polymer containing vinyl phosphonic acids are laminated on a base material.

Japanese Unexamined Patent Publication No. 2008-114520 Japanese Unexamined Patent Publication No. 2004-130654 Japanese Unexamined Patent Publication No. 2006-308806 International release 2014/122942

However, although the vacuum packaging bag using the above-mentioned conventional film has a certain improvement effect in the barrier property, it may not be sufficient as the heat insulating performance of the vacuum heat insulating body. The reason is that the barrier property of the aluminum vapor deposition layer itself is not sufficient, so even if a coat layer is provided, the barrier property of the film may not be sufficient, and the barrier property may decrease due to the physical stress applied during the production of the vacuum insulation body. Since the aluminum vapor deposition layer itself has a relatively high thermal conductivity, it is considered that the heat insulation performance may be deteriorated as a result of heat conduction via the vacuum packaging bag. In particular, heat conduction via the vacuum packaging bag has a large effect on a relatively small vacuum insulation body, which is a big limitation when designing a desired vacuum insulation body. Therefore, there is a demand for a vacuum-packed bag having a low thermal conductivity for a long period of time while maintaining a high level of barrier property of the vacuum-packed bag.

An object of the present invention is a vacuum packaging bag in which the original barrier property of the vacuum packaging bag is maintained at a high level even under physical stress, and the vacuum packaging bag itself has low thermal conductivity, and a vacuum packaging bag using the same. It is to provide a heat insulating body and a multi-layer structure useful for the vacuum packaging bag.

As a result of diligent studies to achieve the above object, the present inventors include a vapor-deposited layer made of an inorganic oxide and a specific organic polymer on at least one surface of the substrate made of a polyvinyl alcohol-based film. A vacuum insulation body in which a core material is covered with a vacuum packaging bag containing a multilayer structure in which layers are laminated and the inside of the vacuum packaging bag is vacuum-sealed to maintain excellent heat insulation performance for a long period of time. I found it. The present inventors have completed the present invention by conducting further studies based on this new finding.

That is, in the present invention, [1] a vapor deposition layer (Y) made of an inorganic oxide and a layer (Z) containing an organic polymer are formed on at least one surface of a base material (X) made of a biaxially stretched polyvinyl alcohol-based film. , The base material (X) / the layer (Y) / the layer (Z) are laminated in this order, and the layer (Y) and the layer (Z) are adjacent to each other, and the layer (Z) The water contact angle of the surface is 10 to 70 °, and the draw ratio of the base material (X) is 2.5 times or more and 4.5 times or less in the vertical direction (MD direction) and 2.5 times in the horizontal direction (TD direction). A multilayer structure having a surface stretching ratio of 7 times or more and 15 times or less.
[2] The multilayer structure of [1], wherein the base material (X) is a film made of an ethylene-vinyl alcohol copolymer having an ethylene content of 10 to 65 mol% and a saponification degree of 90 mol% or more.
[3] The multilayer structure of [1] or [2], wherein the layer (Y) is a vapor-deposited layer containing at least one inorganic oxide selected from the group consisting of aluminum oxide and silicon oxide.
[4] The organic polymer contained in the layer (Z) has 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 [1] to [3]. Any one multilayer structure,
[5] The layer (Z) contains 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 [1] to [4]. Any one of the multilayer structures,
[6] 40 ° C., or less 0% RH oxygen permeability ^{1.0ml / (m 2 · day ·} atm) under the condition of (the carrier gas side) / 65% RH (oxygen supply side), [1] ~ [5], any one of the multilayer structures,
[7] Conditions of 40 ° C., 0% RH (carrier gas side) / 65% RH (oxygen supply side) after holding for 5 minutes in a state of stretching 5% in one direction under the conditions of 23 ° C. and 50% RH. The multilayer structure according to any one of [1] to [6], wherein the oxygen permeability measured below is 2.0 ml / (m ² · day · atm) or less.
[8] 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 any one of [1] to [7]. Vacuum packaging bag,
[9] The present invention relates to a vacuum insulating body comprising the vacuum packaging bag of [8] and a core material arranged inside surrounded by the vacuum packaging bag, the inside of which is depressurized.

The multilayer structure of the present invention maintains a high level of barrier properties originally possessed by the multilayer structure even when subjected to physical stress, and the multilayer structure itself has low thermal conductivity. Therefore, the vacuum-packed bag containing the multilayer structure of the present invention maintains a high level of barrier properties originally possessed by the vacuum-packed bag even when subjected to physical stress, and the vacuum-packed bag itself has low thermal conductivity. Therefore, according to the present invention, the vacuum heat insulating body formed by decompressing and sealing the inside of the vacuum packaging bag can maintain excellent heat insulating performance for a long period of time.

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 exemplified materials, unless otherwise specified, one type may be used alone, or two or more types may be used in combination.

Unless otherwise noted, in the present specification, the meaning of "laminating a specific layer on a specific member (base material, layer, etc.)" means that the specific layer is brought into contact with the member. In addition to the case of laminating, the case of laminating the specific layer on the member with another layer sandwiched between them is included. The same applies to the descriptions of "forming a specific layer on a specific member (base material, layer, etc.)" and "arranging a specific layer on a specific member (base material, layer, etc.)". Further, unless otherwise specified, the meaning of "coating a liquid (coating liquid, etc.) on a specific member (base material, layer, etc.)" means that the liquid is directly applied to the member. In addition, the case where the liquid is applied to another layer formed on the member is included.

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

[Multi-layer structure]
In the multilayer structure of the present invention, a thin-film deposition layer (Y) made of an inorganic oxide and a layer (Z) containing an organic polymer are formed on at least one surface of a base material (X) made of a biaxially stretched polyvinyl alcohol-based film. , The base material (X) / the layer (Y) / the layer (Z) are laminated in this order, and the layer (Y) and the layer (Z) are adjacent to each other, and the layer (Z) The water contact angle of the surface is 10 to 70 °, and the draw ratio of the base material (X) is 2.5 times or more and 4.5 times or less in the vertical direction (MD direction) and 2.5 times in the horizontal direction (TD direction). It is characterized in that it is 4.5 times or more and the surface stretching ratio is 7 times or more and 15 times or less. The vacuum packaging bag and the vacuum heat insulating material produced by using such a multilayer structure can maintain good gas barrier performance and low heat conduction performance for a long period of time. As can be seen from the comparison between Examples and Comparative Examples described later, among the constituent requirements of the multilayer structure of the present invention, the water contact angle of the surface of the layer (Z) is in a certain range, and the base material is used. It is important that the stretch ratio and the surface stretch ratio of (X) are within a certain range. Here, the base material (X), the layer (Y) and / or the layer (Z) in the multilayer structure may be two or more layers. Hereinafter, each material used in the multilayer structure of the present invention will be described in detail.

[Base material (X)]
The multilayer structure of the present invention exhibits excellent gas barrier properties by having a base material (X) made of a biaxially stretched polyvinyl alcohol-based film. The polyvinyl alcohol-based resin may have a vinyl alcohol unit in which the vinyl ester unit is saponified. For example, a polyvinyl alcohol (hereinafter, may be abbreviated as PVA) resin and ethylene-vinyl alcohol can be used together. Examples thereof include polymer (hereinafter, may be abbreviated as EVOH) resin. Further, examples of the PVA resin include a PVA resin obtained by homopolymerizing vinyl acetate and saponifying it, and a modified PVA resin obtained by modifying it. Such modified PVA may be copolymerized or post-modified. These resins will be described below. It should be noted that such polyvinyl alcohol-based resins can be used individually or in combination of two or more.

Examples of PVA include PVA and modified PVA as described above. For example, PVA is produced by homopolymerizing vinyl acetate and further saponifying it. Further, the modified PVA is produced, for example, by copolymerizing vinyl acetate and an unsaturated monomer copolymerizable with vinyl acetate and then saponifying the modified PVA, and the amount of the modification is usually less than 10 mol%. is there.

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 acylated products 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 esters, acrylonitrile, metaacrylonitrile, amides such as diacetoneacrylamide, acrylamide, methacrylicamide, ethylenesulfonic acid, allylsulfonic acid, metaallylsulfonic acid. Olefin sulfonic acids such as or salts thereof, alkyl vinyl ethers, dimethylallyl vinyl ketone, N-vinylpyrrolidone, vinyl chloride, vinyl ethylene carbonate, 2,2-dialkyl-4-vinyl-1,3-dioquinane, 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.

Further, the modified PVA can also be produced by post-modifying PVA. Examples of such a post-denaturation method include a method of acetoacetic esterification, acetalization, urethanization, etherification, grafting, phosphoric acid esterification, and oxyalkyleneization of PVA.

In the present invention, it is preferable that the degree of polymerization of PVA is 1,100 or more and the degree of saponification is 90 mol% or more. The degree of polymerization of PVA is more preferably 1,100 to 4,000, and even more preferably 1,200 to 2,600. If the degree of polymerization is too low, the mechanical strength of the obtained vacuum packaging bag tends to decrease, while if the degree of polymerization is too high, the processability during film formation and stretching tends to decrease. Further, the saponification degree of PVA is more preferably 95 to 100 mol%, further preferably 99 to 100 mol%. If the degree of saponification is too low, the water resistance is lowered and the gas barrier property is easily affected by humidity, which is not preferable.

EVOH is usually obtained by saponifying a copolymer of 10 to 60 mol% of ethylene and a vinyl ester, and vinyl acetate is a typical example of such vinyl ester, but other vinyl esters are used. Fatty acid vinyl esters (vinyl propionate, vinyl pivalate, etc.) can also be used.

Further, EVOH can also 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, as long as the object of the present invention is not impaired, other copolymerizable monomers such as propylene and butylene; unsaturated (meth) acrylic acid, methyl (meth) acrylic acid, ethyl (meth) acrylic acid and the like are unsaturated. Carboxylic acid or an ester thereof; vinylpyrrolidone such as N-vinylpyrrolidone can be copolymerized.

The ethylene content of EVOH is preferably 10 to 65 mol%, more preferably 15 to 55 mol%, and even more preferably 20 to 50 mol% from the viewpoint of exhibiting good stretchability. .. If the ethylene content is less than 10 mol%, the melt moldability tends to deteriorate, while if it exceeds 65 mol%, the gas barrier property may be insufficient. 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, and further preferably 99 mol% or more. If the degree of saponification is less than 90 mol%, the gas barrier property under high humidity tends to decrease. On the other hand, the upper limit of the saponification degree of EVOH is preferably 100 mol%, more preferably 99.99 mol%. When the EVOH resin contains two or more different EVOH formulations, each ethylene content or saponification degree calculated from the compounding weight ratio is defined as the ethylene content or saponification degree of the EVOH resin.

The EVOH resin used in the present invention preferably contains additives such as various acids and metal salts from the viewpoint of thermal stability and viscosity adjustment. Examples of the additive include alkali metal salts, carboxylic acids and / or salts thereof, phosphoric acid compounds and boron compounds.

As the base material (X) used in the present invention, a film formed by using the above-mentioned polyvinyl alcohol-based resin can be used. Such a film forming method may also be known and is not particularly limited. 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. The film is formed by a melt molding method in which melt extrusion is performed by a machine.

From the viewpoint of dimensional stability and gas barrier properties, the polyvinyl alcohol-based resin film has a draw ratio of 2.5 times or more and 4.5 times or less in the vertical direction (MD direction) and 2.5 times or more in the horizontal direction (TD direction) 4. A biaxially stretched film having a stretching ratio of 5 times or less and a surface stretching ratio of 7 times or more and 15 times or less is used. This is very important. From the viewpoint of thickness uniformity, barrier properties, mechanical properties, and film formation properties, the draw ratio is 2.5 times or more and 3.5 times or less in the vertical direction, 2.5 times or more and 3.5 times or less in the horizontal direction, and surface stretching. The magnification is preferably 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) used in the present invention, a biaxially stretched PVA resin film and a biaxially stretched EVOH resin film can be used, and a biaxially stretched EVOH resin film is preferable.

The thickness of the base material (X) used in the present invention is not particularly limited, but is preferably 5 to 100 μm, more preferably 8 to 50 μm from the viewpoint of industrial productivity. More specifically, the thickness of the biaxially stretched PVA resin film is preferably 5 to 50 μm, more preferably 8 to 30 μm. The thickness of the biaxially stretched EVOH resin film is preferably 5 to 50 μm, more preferably 10 to 40 μm.

[Layer (Y)]
The layer (Y) contained in the multilayer structure of the present invention is composed of a vapor-deposited layer made of an inorganic oxide. The layer (Y) preferably has a barrier property against oxygen gas and water vapor. As the layer (Y), one having a light-shielding property or one having a transparency property can be appropriately used. Examples of the transparent inorganic oxide-deposited layer include a layer formed from an inorganic oxide such as aluminum oxide, silicon oxide, silicon nitride, magnesium oxide, tin oxide, or a mixture thereof. Among these, the layer formed from aluminum oxide, silicon oxide, and a mixture thereof is preferable from the viewpoint of excellent barrier property against oxygen gas and water vapor.

The preferred thickness of the layer (Y) varies depending on the type of component constituting the layer (Y), but is usually in the range of 2 to 500 nm. Within this range, a thickness that improves the barrier properties and mechanical properties of the multilayer structure may be selected. When the thickness of the layer (Y) is less than 2 nm, the reproducibility of the barrier property expression of the inorganic oxide-deposited layer to oxygen gas and water vapor tends to decrease, and the inorganic oxide-deposited layer has sufficient barrier property. May not be expressed. Further, when the thickness of the layer (Y) exceeds 500 nm, the barrier property of the inorganic oxide-deposited layer tends to be easily lowered when the multilayer structure is pulled or bent. The thickness of the inorganic oxide-deposited layer is more preferably in the range of 5 to 200 nm, and even more preferably in the range of 10 to 100 nm.

Examples of the method for forming the layer (Y) include a vacuum deposition method, a sputtering method, an ion plating method, and a chemical vapor deposition method (CVD). Among these, the vacuum 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 substrate on which the inorganic oxide-deposited layer is formed and the denseness of the inorganic oxide-deposited layer, a plasma assist method or an ion beam assist method may be adopted for vapor deposition. Further, in order to obtain an inorganic oxide thin-film deposition layer, a reaction vapor deposition method may be adopted in which oxygen gas or the like is blown into the vapor deposition to cause a reaction.

[Layer (Z)]
The layer (Z) contained in the multilayer structure of the present invention contains an organic polymer, is adjacent to the layer (Y), and has a water contact angle of 10 to 70 ° on the surface of the layer (Z). Here, "adjacent" means that at least one set of layers (Y) and layers (Z) are directly laminated in the multilayer structure.
The organic polymer contained in the layer (Z) is not necessarily limited as long as it is a substance having a surface water contact angle of 10 to 70 ° when the layer is formed, but among them, a hydroxyl group, a carboxylic acid group and phosphorus. It is preferable to include an organic polymer having at least one functional group selected from the group consisting of functional groups containing atoms. 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 polyvinyl alcohol-based resins 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. A polymer can be used.

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 which phosphate and phosphonic acid groups are preferred, with phosphonic acid groups being more preferred. 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 may be 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) contained in the multilayer structure of the present invention further contains 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. You can go out. 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).

(Hydrolyzed condensate of compound (L))
At least one of the compound (A) and / or the compound (B) described below can be applied to the compound (L). Hereinafter, the compound (A) and the compound (B) will be described.

The compound (A) is at least one compound represented by the following chemical formula (I).
M ¹ (OR ¹ ) _n X ¹ _k Z ¹ _m-n-k ... (I)
In the chemical formula (I), M ¹ is Si, Al, Ti, Zr, Cu, Ca, Sr, Ba, Zn, B, Ga, Y, Ge, Pb, P, Sb, V, Ta, W, La and Represents an atom selected from Nd. M ¹ is preferably Si, Al, Ti, or Zr, and particularly preferably Si. Further, in the chemical formula (I), R ¹ is an alkyl group such as a methyl group, an ethyl group, an n-propyl group, an iso-propyl group, an n-butyl group and a t-butyl group, and is preferably a methyl group or an ethyl group. Is the basis. Further, in the chemical formula (I), X ¹ represents a halogen atom. Examples of the halogen atom represented by X ¹ include a chlorine atom, a bromine atom, an iodine atom and the like, and a chlorine atom is preferable. Further, in the chemical formula (I), Z ¹ represents an alkyl group substituted with a functional group having reactivity with a carboxyl group. Here, examples of the functional group having reactivity with the carboxyl group include an epoxy group, an amino group, a hydroxyl group, a halogen atom, a mercapto group, an isocyanate group, a ureido group, an oxazoline group, a carbodiimide group and the like. , Amino group, isocyanate group, ureido group, or halogen atom is preferable, and at least one selected from, for example, an epoxy group, an amino group and an isocyanate group. As the alkyl group substituted with such a functional group, the above-mentioned one can be exemplified. Further, in the chemical formula (I), m is equal to the valence of the metal element ^{M 1.} In the chemical formula (I), n represents an integer of 0 to (m-1). Further, in the chemical formula (I), k represents an integer of 0 to (m-1), and 1 ≦ n + k ≦ (m-1).

Specific examples of the compound (A) include γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropyltrichlorosisilane, γ-aminopropyltrimethoxysilane, and γ-. Aminopropyltriethoxysilane, γ-aminopropyltrichlorosilane, γ-chloropropyltrimethoxysilane, γ-chloropropyltriethoxysilane, γ-chloropropyltrichlorosilane, γ-bromopropyltrimethoxysilane, γ-bromopropyltriethoxy Silane, γ-Bromopropyltrichlorosilane, γ-mercaptopropyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, γ-mercaptopropyltrichlorosilane, γ-isocyanuppropyltrimethoxysilane, γ-isocyanabotriethoxysilane, γ- Examples thereof include isocyanatepropyltrichlorosilane, γ-ureidopropyltrimethoxysilane, γ-ureidopropyltriethoxysilane, and γ-ureidopropyltrichlorosilane. Preferred compounds (A) include γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-chloropropyltrimethoxysilane, γ-chloropropyltriethoxysilane, and γ-aminopropyltrimethoxy. Examples thereof include silane and γ-aminopropyltriethoxysilane.

The compound (B) is at least one compound represented by the following chemical formula (II).
M ² (OR ² ) _q R ³ _p-q-r X ² _r ... (II)
In the chemical formula (II), M ² is Si, Al, Ti, Zr, Cu, Ca, Sr, Ba, Zn, B, Ga, Y, Ge, Pb, P, Sb, V, Ta, W, La and It represents an atom selected from Nd, preferably Si, Al, Ti, or Zr, and particularly preferably Si, Al, or Ti. Further, in the chemical formula (II), R ² represents an alkyl group such as a methyl group, an ethyl group, an n-propyl group, an iso-propyl group, an n-butyl group and a t-butyl group, and is preferably a methyl group. Or it is an ethyl group. Further, in the chemical formula (II), X ² represents a halogen atom. Examples of the halogen atom represented by X ² include a chlorine atom, a bromine atom and an iodine atom, but a chlorine atom is preferable. Further, in the chemical formula (II), R ³ represents an alkyl group, an aralkyl group, an aryl group, or an alkenyl group. Examples of the alkyl group represented by R ³ include a methyl group, an ethyl group, an n-propyl group, an iso-propyl group, an n-butyl group, a t-butyl group, an n-octyl group and the like. Examples of the aralkyl group represented by R ³ include a benzyl group, a phenethyl group, and a trityl group. Examples of the aryl group represented by R ³ include a phenyl group, a naphthyl group, a tolyl group, a xsilyl group, and a mesitylene group. Examples of the alkenyl group represented by R ³ include a vinyl group and an allyl group. Further, in the chemical formula (II), p is equal to the valence of the metal element M2. In formula (II), q represents an integer from 0 to p. Further, in the chemical formula (II), r represents an integer of 0 to p, and 1 ≦ q + r ≦ p.

In the chemical formulas (I) and (II), M ¹ and M ² may be the same or different. Further, R ¹ and R ² may be the same or different.

Specific examples of the compound (B) include tetramethoxysilane, tetraethoxysilane, methyltrimethoxysilane, ethyltrimethoxysilane, octyltrimethoxysilane, phenyltrimethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, and chlorotri. Silicon alkoxides such as methoxysilane, chlorotriethoxysilane, dichlorodimethoxysilane, dichlorodiethoxysilane, trichloromethoxysilane, trichloroethoxysilane; halogenated silanes such as vinyltrichlorosilane, tetrachlorosilane, tetrabromosilane; tetramethoxytitanium, tetra Akoxytitanium compounds such as ethoxytitanium, tetraisopropoxytitanium, and methyltriisopropoxytitanium; titanium halides such as tetrachlorotitanium; trimethoxyaluminum, triethoxyaluminum, triisopropoxyaluminum, methyldiisopropoxyaluminum, tributoxyaluminum , Alkoxyaluminum compounds such as diethoxyaluminum chloride; alkoxyzylene compounds such as tetraethoxyzylzyl, tetraisopropoxyzaldehyde, and methyltriisopropoxyzaldehyde.

When the compound (L) is hydrolyzed, at least a part of the halogen and alkoxy groups of the compound (L) is replaced with a hydroxyl group. Further, the hydrolyzate is condensed to form a compound in which metal elements are bonded via oxygen. When this condensation is repeated, it becomes a compound that can be regarded as a substantially metal oxide. Here, in order for this hydrolysis and condensation to occur, it is important that a halogen atom or an alkoxy group is bonded to the metal, and if the halogen atom or the alkoxy group is not bonded, the hydrolysis or condensation reaction occurs. It is difficult to obtain the effect of improving the barrier property of the layer (Z) derived from the hydrolyzed condensate of the compound (L) because it is absent or extremely slow.

The hydrolyzed condensate of compound (L) preferably has a degree of condensation P defined below of 65 to 99%, more preferably 70 to 99%, and further preferably 75 to 99%. preferable. The degree of condensation P (%) in the hydrolyzed condensate of compound (L) is calculated as follows.

A compound in which the total number of alkoxy groups and halogen atoms in one molecule of compound (L) is a, and the total number of condensed alkoxy groups and halogen atoms in the hydrolyzed condensate of compound (L) is i (pieces). When the ratio of (L) is yi (%) in all the compounds (L), {(i / a) × yi} for each value of an integer (including 1 and a) in which i is 1 to a. And add them together. That is, the degree of condensation P (%) is defined by the following mathematical formula.

The above-mentioned yi value can be measured by solid NMR (DD / MAS method) or the like for the hydrolyzed condensate of the compound (L) in the layer (Z).

The hydrolyzed condensate was a compound (L), a compound (L) partially hydrolyzed, a compound (L) completely hydrolyzed, or a compound (L) partially hydrolyzed and condensed. It can be produced, for example, by a method used in a known sol-gel method, using a compound (L) completely hydrolyzed and a part thereof condensed, or a combination thereof as a raw material. These raw materials may be produced by a known method or commercially available materials 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. Specifically, for example, a product obtained by hydrolyzing and condensing tetramethoxysilane to form a linear condensate of 2 to 10 dimers can be used as a raw material.

The number of molecules condensed in the hydrolyzed condensate of compound (L) in the composition constituting the layer (Z) depends on the amount of water used for hydrolysis and condensation, the type and concentration of catalyst, and the hydrolysis condensation. It can be controlled by the temperature to be performed.

The method for producing the hydrolyzed condensate of the compound (L) is not particularly limited, but in a typical example of the sol-gel method, hydrolysis and condensation are carried out by adding water, an acid and an alcohol to the above-mentioned raw materials.

In the following, the compound (L) may be described as a metal alkoxide (a compound containing a metal to which an alkoxy group is bonded), but a compound containing a metal to which a halogen is bonded may be used instead of the metal alkoxide.

As described above, the compound (L) can be at least one of the compound (A) and / or the compound (B). When the compound (L) contains both the compound (A) and the compound (B), the gas barrier property of the obtained multilayer structure is good, which is preferable. Then, the compound (L) is substantially composed of both the compound (A) and the compound (B), and the molar ratio of the compound (A) / compound (B) is 0.5 / 99.5 to 40 /. More preferably, it is in the range of 60. When the compound (A) and the compound (B) are used in combination at this ratio, the obtained multilayer structure is excellent in mechanical properties such as gas barrier property, tensile strength and elongation, appearance, and handleability. The molar ratio of compound (A) / compound (B) is more preferably in the range of 3/97 to 40/60, and even more preferably in the range of 4/96 to 30/70.

Further, in another example of the present invention, an organic group having at least one characteristic group selected from a halogen atom, a mercapto group and a hydroxyl group may be further bonded to the metal atom of the compound (L). Hereinafter, the compound (L) to which such an organic group is bonded may be referred to as a compound (L').

For example, silicon, tin, and titanium can be used as the metal atom of the compound (L'). Although the silicon atom may be classified as a non-metal element, it is treated as a metal element in this specification. Among these, the silicon atom is preferable in that the reaction is easily controlled, a stable product can be obtained, and the product is easily available. The silicon atom has an organic group having at least one characteristic group selected from a halogen atom, a mercapto group and a hydroxyl group bonded to the silicon atom and at least one characteristic group selected from a halogen atom and an alkoxy group. Other substituents may be bonded to the silicon atom as long as the effects of the present invention can be obtained. Such other substituents include, for example, hydrogen atom, alkyl group, alkenyl group, aryl group, aralkyl group and amino group. Examples of the compound (L') containing a silicon atom include a compound represented by the following formula (I'), allyl (chloropropyl) dichlorosilane, bis (chloromethyldimethylsiloxy) benzene, and N- (3- (3-). Examples thereof include triethoxysilylpropyl) gluconamide and N- (3-triethoxysilylpropyl) -4-hydroxybutylamide.

The compound (L') may contain at least one compound (A') represented by the following chemical formula (I').
Si (OR ¹ ) _s R ⁴ _t X ¹ _u Z ² _4-s-t-u ... (I')
[In the chemical formula (I'), R ¹ and R ⁴ each independently represent an alkyl group. X ¹ represents halogen. Z ² represents an organic group having at least one characteristic group selected from a halogen atom, a mercapto group and a hydroxyl group. s represents an integer from 0 to 3. t represents an integer from 0 to 2. u represents an integer from 0 to 3. 1 ≦ s + u ≦ 3. 1 ≦ s + t + u ≦ 3. ]
R ¹ and R ⁴ are independently alkyl groups such as methyl group, ethyl group, n-propyl group, iso-propyl group, n-butyl group and t-butyl group, and preferably methyl group or ethyl group. Is. Examples of the halogen represented by X ¹ include chlorine, bromine and iodine, and chlorine is preferable.

The organic group Z ² may be a hydrocarbon group (having a carbon number of, for example, about 1 to 5) substituted with at least one characteristic group selected from a halogen atom, a mercapto group, an isocyanate group, a ureido group, and a hydroxyl group. .. As such an organic group, for example, a chloromethyl group, a chloroethyl group, a chloropropyl group, a chloroethylmethyl group, or a chloro group thereof is changed to a bromo group, an iodine group, a fluorine group, a mercapto group, or a hydroxyl group. Organic groups can be mentioned. Further, the organic group Z ² may be an organic group having at least one characteristic group selected from a halogen atom, a mercapto group and a hydroxyl group and an amide structure.

Specific examples of the compound (A') in which t is 1 or 2 in the formula (I') include, for example, chloromethylmethyldimethoxysilane, chloromethyldimethylmethoxysilane, 2-chloroethylmethyldimethoxysilane, and 2-chloroethyl. Dimethylmethoxysilane, 3-chloropropylmethyldimethoxysilane, 3-chloropropyldimethylmethoxysilane, mercaptomethylmethyldimethoxysilane, mercaptomethyldimethylmethoxysilane, 2-mercaptoethylmethyldimethoxysilane, 2-mercaptoethyldimethylmethoxysilane, 3- Examples thereof include mercaptopropylmethyldimethoxysilane, 3-mercaptopropyldimethylmethoxysilane, and bis (chloromethyl) methylchlorosilane. Further, a compound in which the methoxy group portion of these compounds is an alkoxy group such as an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, or a t-butoxy group or a chlorine group may be used.

Specific examples of the compound (A') in which t is 0 in the formula (I') include, for example, chloromethyltrimethoxycisilane, 2-chloroethyltrimethoxysilane, 3-chloropropyltrimethoxysilane, and 2-chloro. Propyltrimethoxysilane, 4-chlorobutyltrimethoxysilane, 5-chloropentyltrimethoxysilane, 6-chlorohexyltrimethoxysilane, (dichloromethyl) dimethoxycysilane, (dichloroethyl) dimethoxysilane, (dichloropropyl) dimethoxysilane , (Trichloromethyl) methoxycisilane, (trichloroethyl) methoxysilane, (trichloropropyl) methoxysilane, mercaptomethyltrimethoxysilane, 2-mercaptoethyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 2-mercaptopropyltri Methoxysilane, 4-mercaptobutyltrimethoxysilane, 5-mercaptopentyltrimethoxysilane, 6-mercaptohexyltrimethoxysilane, (dimercaptomethyl) dimethoxysisilane, (dimercaptoethyl) dimethoxysilane, (dimercaptopropyl) dimethoxy Silane, (Trimercaptomethyl) methoxycisilane, (Trimercaptoethyl) methoxysilane, (Trimercaptopropyl) methoxysilane, Fluoromethyltrimethoxycisilane, 2-Fluoroethyltrimethoxysilane, 3-Fluoropropyltrimethoxysilane, Bromomethyltrimethoxycisilane, 2-bromoethyltrimethoxysilane, 3-bromopropyltrimethoxysilane, iodomethyltrimethoxycisilane, 2-iodoethyltrimethoxysilane, 3-iodopropyltrimethoxysilane, (chloromethyl) Phenyltrimethoxycisilane, (chloromethyl) phenylethyltrimethoxysilane, 1-chloroethyltrimethoxysilane, 2- (chloromethyl) allyltrimethoxysilane, (3-chlorocyclohexyl) trimethoxysilane, (4-chlorocyclohexyl) ) Trimethoxysilane, (mercaptomethyl) phenyltrimethoxycisilane, (mercaptomethyl) phenylethyltrimethoxysilane, 1-mercaptoethyltrimethoxysilane, 2- (mercaptomethyl) allyltrimethoxysilane, (3-mercaptocyclohexyl) Trimethoxysilane, (4-mercaptocyclohexyl) trimethoxysilane, N- (3-to Examples thereof include lyethoxysilylpropyl) gluconamide and N- (3-triethoxysilylpropyl) -4-hydroxybutylamide. Further, a compound in which the methoxy group portion of these compounds is an alkoxy group such as an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, or a t-butoxy group or a chlorine group may be used.

The compound (L') is chloromethyltrimethoxycisilane, chloromethyltriethoxysisilane, chloromethyltrichlorosilane, 2-chloroethyltrimethoxysilane, 2-chloroethyltriethoxysilane, 2-chloroethyltrichlorosilane, 3 -Chloropropyltrimethoxysilane, 3-chloropropyltriethoxysilane, 3-chloropropyltrichlorosilane, mercaptomethyltrimethoxysilane, mercaptomethyltriethoxysilane, mercaptomethyltrichlorosilane, 2-mercaptoethyltrimethoxysilane, 2-mercapto Ethyltriethoxysilane, 2-mercaptoethyltrichlorosilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 3-mercaptopropyltrichlorosilane, (chloromethyl) phenyltrimethoxycisilane, (chloromethyl) phenyl Triethoxysisilane, (chloromethyl) phenyltrichlorosilane, (chloromethyl) phenylethyltrimethoxysilane, (chloromethyl) phenylethyltriethoxysilane, (chloromethyl) phenylethyltrichlorosilane, (mercaptomethyl) phenyltrimethoxysi Silane, (mercaptomethyl) phenyltriethoxysisilane, (mercaptomethyl) phenyltrichlorosilane, (mercaptomethyl) phenylethyltrimethoxysilane, (mercaptomethyl) phenylethyltriethoxysilane, (mercaptomethyl) phenylethyltrichlorosilane, hydroxy Methyltrimethoxysilane, hydroxyethyltrimethoxysilane, hydroxypropyltrimethoxysilane, N- (hydroxyethyl) -N-methylaminopropyltrimethoxysilane, N- (3-triethoxysilylpropyl) gluconamide, and N-( It preferably contains at least one compound selected from 3-triethoxysilylpropyl) -4-hydroxybutylamide.

Among these, the compound (L') is chloromethyltrialkoxysilane, chloromethyltrichlorosilane, 2-chloroethyltrialkoxysilane, 2-chloroethyltrichlorosilane, 3-chloropropyltrialkoxysilane, 3-chloropropyltri. Chlorosilane, mercaptomethyltrialkoxysilane, mercaptomethyltrichlorosilane, 2-mercaptoethyltrialkoxysilane, 2-mercaptoethyltrichlorosilane, 3-mercaptopropyltrialkoxysisilane, 3-mercaptopropyltrichlorosilane, N- (3-tri) It is preferable to contain at least one compound selected from (alkoxysilylpropyl) gluconamide and N- (3-trialkoxysilylpropyl) -4-hydroxybutylamide. By using these compounds, a multilayer structure having excellent transparency can be obtained. Particularly preferred compounds (L') include chloromethyltrimethoxycisilane, chloromethyltriethoxysisilane, 3-chloropropyltrimethoxysilane, 3-chloropropyltriethoxysilane, mercaptomethyltrimethoxysilane, and mercaptomethyltriethoxy. Examples thereof include silane, 3-mercaptopropyltrimethoxysilane, and 3-mercaptopropyltriethoxysilane. By using these compounds as the compound (L'), a multilayer structure having both excellent gas barrier properties and transparency can be obtained. According to the present invention, it is possible to obtain a multilayer structure having a haze value of 3% or less and excellent transparency.

As these compounds (L'), commercially available compounds may be used, or they may be synthesized by a known method.

In the above other example, the compound (L) may further contain at least one compound (B) represented by the above-mentioned chemical formula (II) in addition to the compound (A'). In the chemical formulas (I') and (II), R ¹ and R ² may be the same or different.

When compound (L) contains compound (A') and compound (B), the molar ratio of compound (A') / compound (B) is in the range of 0.1 / 99.9 to 40/60. It is preferably in the range of 0.5 / 99.5 to 30/70, more preferably in the range of 1/99 to 20/80 (for example, 5/95 to 20/80). By using the compound (A') and the compound (B) in combination at this ratio, a multilayer structure having excellent performance such as barrier properties, mechanical properties such as tensile strength and elongation, appearance, and handleability can be obtained.

(Layer (Z1))
In particular, a hydrolyzed condensate of at least one compound (L) in which the layer (Z) contains a metal atom to which at least one characteristic group selected from a halogen atom and an alkoxy group is bonded, and a carboxyl group and a carboxylic acid anhydride group. The composition comprises a neutralized product of a polymer containing at least one functional group selected from the above, and at least a part of the -COO- group contained in the at least one functional group is a metal ion having a valence of 2 or more. In the case of neutralization, there were cases where the barrier property was further improved. In the present specification, the layer (Z) having the characteristics is particularly referred to as a layer (Z1). Although the cause of the further improvement of the barrier property has not been clarified, there is an effect that the layer (Z1) itself has the gas barrier property and the adhesion between the layer (Y) and the layer (Z1) is improved. It is thought that this is the reason.

The layer (Z1) contains a neutralized polymer containing at least one functional group selected from a carboxyl group and a carboxylic acid anhydride group. The content of the neutralized product of the polymer in the layer (Z1) is not particularly limited, and can be, for example, in the range of 25% by weight to 95% by weight. The neutralized product of this polymer is at least the above with respect to a polymer containing at least one functional group selected from a carboxyl group and a carboxylic acid anhydride group (hereinafter, may be referred to as a “carboxylic acid-containing polymer”). It is a polymer obtained by neutralizing at least a part of one functional group with a metal ion having a valence of 2 or more. The carboxylic acid-containing polymer has two or more carboxyl groups or one or more carboxylic acid anhydride groups in one molecule of the polymer. Specifically, it is possible to use a polymer containing two or more structural units having one or more carboxyl groups, such as an acrylic acid unit, a methacrylic acid unit, a maleic acid unit, and an itaconic acid unit, in one molecule of the polymer. it can. Further, a polymer containing a structural unit having a structure of a carboxylic acid anhydride such as a maleic anhydride unit or a phthalic anhydride unit can also be used. The structural unit having one or more carboxyl groups and / or the structural unit having a structure of carboxylic acid anhydride (hereinafter, both may be collectively abbreviated as carboxylic acid-containing unit (C)) may be one kind. Two or more types may be included.

Further, by setting the content of the carboxylic acid-containing unit (C) in the total structural units of the carboxylic acid-containing polymer to 10 mol% or more, a gas-barrier laminate having good gas-barrier properties under high humidity can be obtained. .. The content is more preferably 20 mol% or more, further preferably 40 mol% or more, and particularly preferably 70 mol% or more. When the carboxylic acid-containing polymer contains both a structural unit containing one or more carboxyl groups and a structural unit having a structure of a carboxylic acid anhydride, the total of both may be in the above range.

The structural unit other than the carboxylic acid-containing unit (C), which may be contained in the carboxylic acid-containing polymer, is not particularly limited, but is limited to methyl acrylate unit, methyl methacrylate unit, ethyl acrylate unit, and methacrylic acid. Structural units derived from (meth) acrylic acid esters such as ethyl units, butyl acrylate units and butyl methacrylate units; structural units derived from vinyl esters such as vinyl formate units and vinyl acetate units; styrene units, p-Styrene sulfonic acid unit; One or more kinds of structural units selected from structural units derived from olefins such as ethylene unit, propylene unit, and isobutylene unit can be mentioned. When the carboxylic acid-containing polymer contains two or more structural units, the carboxylic acid-containing polymer is in the form of an alternating copolymer, a random copolymer, a block copolymer, or even a taper. It may be in any form of copolymer of type.

Preferred examples of the carboxylic acid-containing polymer include polyacrylic acid, polymethacrylic acid, and poly (acrylic acid / methacrylic acid). The carboxylic acid-containing polymer may be one kind or a mixture of two or more kinds of polymers. For example, at least one polymer selected from polyacrylic acid and polymethacrylic acid may be used. Specific examples of the case containing the above-mentioned other structural units include ethylene-maleic anhydride copolymer, styrene-maleic anhydride copolymer, isobutylene-maleic anhydride alternating copolymer, and ethylene-acrylic acid. Examples thereof include a copolymer and a saponified product of an ethylene-ethyl acrylate copolymer.

The molecular weight of the carboxylic acid-containing polymer is not particularly limited, but the number average molecular weight is 5,000 or more because the obtained gas-variable laminate has excellent gas barrier properties and mechanical properties such as drop impact strength. It is preferably 10,000 or more, more preferably 20,000 or more. The upper limit of the molecular weight of the carboxylic acid-containing polymer is not particularly limited, but is generally 1.5 million or less.

Further, the molecular weight distribution of the carboxylic acid-containing polymer is not particularly limited, but the carboxylic acid-containing polymer is good from the viewpoint of improving the surface appearance such as haze of the gas barrier laminate and the storage stability of the solution. The molecular weight distribution represented by the ratio of weight average molecular weight / number average molecular weight of is preferably in the range of 1 to 6, more preferably in the range of 1 to 5, and further preferably in the range of 1 to 4. preferable.

The polymer constituting the layer (Z1) is at least a part of at least one functional group (hereinafter, may be referred to as a functional group (F)) selected from the carboxyl group and the carboxylic acid anhydride group of the carboxylic acid-containing polymer. Is neutralized with a metal ion having a valence of 2 or more. In other words, this polymer contains a carboxyl group neutralized with a divalent or higher metal ion.

In the polymer constituting the layer (Z1), for example, 10 mol% or more (for example, 15 mol% or more) of the -COO- group contained in the functional group (F) is neutralized with a divalent or higher metal ion. .. The carboxylic acid anhydride group is considered to contain two -COO- groups. That is, when a molar carboxyl group and b molar carboxylic acid anhydride group are present, the —COO− group contained therein is (a + 2b) mol in total. The proportion of the -COO-group contained in the functional group (F) that is neutralized with a divalent or higher metal ion is preferably 20 mol% or more, more preferably 30 mol% or more, and further. It is preferably 40 mol% or more, and particularly preferably 50 mol% or more (for example, 60 mol% or more). The upper limit of the proportion of the -COO-group contained in the functional group (F) that is neutralized with a divalent or higher metal ion is not particularly limited, but can be, for example, 95 mol% or less. By neutralizing the carboxyl groups and / or carboxylic acid anhydride groups in the carboxylic acid-containing polymer with divalent or higher metal ions, the layer (Z1) is made under both dry and high humidity conditions. Shows good gas barrier properties.

The degree of neutralization (degree of ionization) of the functional group (F) is determined by measuring the infrared absorption spectrum of the layer (Z1) by the ATR (total reflection measurement) method, or by scraping the layer (Z1) from the multilayer structure. The infrared absorption spectrum can be obtained by measuring the KBr method. Before neutralization peak attributed to C = O stretching vibration of the carboxyl group or carboxylic anhydride group (ionization front) was observed in the range of 1600cm ^-1 ~1850cm ^-1, after being neutralized (ionized) C = O stretching vibration of the carboxyl group is to be observed in a range of 1500cm ^-1 ~1600cm ^-1, it can be evaluated by separating the two in the infrared absorption spectrum. Specifically, the ratio can be obtained from the maximum absorbance in each range, and the degree of ionization of the polymer constituting the layer (Z1) in the multilayer structure can be calculated using a calibration curve prepared in advance. The calibration curve can be created by measuring the infrared absorption spectra of a plurality of standard samples having different degrees of neutralization.

It is important that the metal ion that neutralizes the functional group (F) is divalent or higher. When the functional group (F) is unneutralized or neutralized only by monovalent ions described later, a layer (Z1) having good gas barrier properties cannot be obtained. However, when the functional group (F) is neutralized with a small amount of monovalent ions (cations) in addition to divalent or higher metal ions, the haze of the multilayer structure is reduced and the surface appearance is improved. It will be good. As described above, the present invention includes the case where the functional group (F) of the carboxylic acid-containing polymer is neutralized by both a divalent or higher valent metal ion and a monovalent ion. Examples of divalent or higher metal ions include calcium ion, magnesium ion, divalent iron ion, trivalent iron ion, zinc ion, divalent copper ion, lead ion, divalent mercury ion, and barium ion. Examples thereof include nickel ion, zirconium ion, aluminum ion and titanium ion. For example, as the divalent or higher metal ion, at least one ion selected from calcium ion, magnesium ion, barium ion and zinc ion may be used.

In the present invention, 0.1 to 10 mol% of the -COO- group contained in the functional group (F) (carboxyl group and / or carboxylic acid anhydride) of the carboxylic acid-containing polymer is a monovalent ion. It is preferable that they are summed. However, when the degree of neutralization by monovalent ions is high, the gas barrier property of the layer (Z1) is lowered. The degree of neutralization of the functional group (F) by the monovalent ion is more preferably in the range of 0.5 to 5 mol%, further preferably in the range of 0.7 to 3 mol%. Examples of the monovalent ion include ammonium ion, pyridinium ion, sodium ion, potassium ion, lithium ion and the like, and ammonium ion is preferable.

The content of the inorganic component in the composition constituting the layer (Z1) is preferably in the range of 5 to 50% by weight from the viewpoint of improving the gas barrier property of the layer (Z1). This content is more preferably in the range of 10 to 45% by weight, further preferably in the range of 15 to 40% by weight, still more preferably in the range of 25 to 40% by weight. The content of the inorganic component in the composition can be calculated from the weight of the raw material used in preparing the composition. That is, compound (L), compound (L) partially hydrolyzed, compound (L) completely hydrolyzed, compound (L) partially hydrolyzed and condensed, compound (L). Is completely hydrolyzed and a part of it is condensed, or a combination of these is completely hydrolyzed and condensed to become a metal oxide, and the weight of the metal oxide is calculated. Then, the calculated weight of the metal oxide is regarded as the weight of the inorganic component in the composition, and the content rate of the inorganic component is calculated. When adding an inorganic additive such as a metal salt, a metal complex, or a metal oxide as described later, the weight of the added inorganic additive is directly added to the weight of the inorganic component. More specifically, when the calculation of the weight of the metal oxide is described more specifically, when the compound (A) represented by the chemical formula (I) is completely hydrolyzed and condensed, the composition formula is M ¹ O _{(n + k) / 2} Z ¹ It is a compound represented by _mn-k . Of this compound, the portion of M ¹ O _{(n + k) / 2} is a metal oxide. Z ¹ is not included in the inorganic component and is regarded as an organic component. When the compound (B) represented by the chemical formula (II) is completely hydrolyzed and condensed, the composition formula becomes a compound represented by M ² O _{(q + r) / 2} R ³ _p-q-r . Of these, the portion of M ² O _{(q + r) / 2} is a metal oxide. A component obtained by adding the weight of this metal oxide up to the first step to all components excluding volatile components such as a solvent and a compound generated in the process of changing the above-mentioned compound (L) into a metal oxide. The value obtained by multiplying the value divided by 100 by the weight of the above is the content rate (%) of the inorganic component referred to here.

Further, the composition constituting the layer (Z1) may contain carbonate, hydrochloride, nitrate, hydrogen carbonate, sulfate, hydrogen sulfate, phosphate, if desired, within a range that does not impair the effects of the present invention. Inorganic acid metal salts such as borates and aluminates; organic acid metal salts such as oxalates, acetates, tartrates and stearate; acetylacetonate metal complexes such as aluminum acetylacetonate, titanosen Cyclopentadienyl metal complex such as, metal complex such as cyano metal complex; layered clay compound, cross-linking agent, polyalcohols or other polymer compounds, plasticizer, antioxidant, ultraviolet absorber, flame retardant, etc. It may be contained. The composition constituting the gas barrier layer is a fine powder of a metal oxide produced by hydrolyzing and condensing the above metal alkoxide in a wet manner; a metal oxide prepared by hydrolyzing, condensing or burning a metal alkoxide in a dry manner. Fine powder; may contain silica fine powder prepared from water glass and the like.

By further adding polyalcohols to the composition constituting the layer (Z1) of the present invention, the surface appearance of the gas barrier laminate is improved. More specifically, by containing polyalcohols, cracks are less likely to occur in the layer (Z1) during the production of the gas barrier laminate, and a gas barrier laminate having a good surface appearance can be obtained.

Such polyalcohols used in the present invention are compounds having at least two or more hydroxyl groups in the molecule, and include low molecular weight compounds to high molecular weight compounds. Preferably, polyvinyl alcohol, partially saponified product of polyvinyl acetate, ethylene-vinyl alcohol copolymer, polyethylene glycol, polyhydroxyethyl (meth) acrylate, polysaccharides such as starch, and polysaccharides derived from polysaccharides such as starch. It is a high molecular weight compound such as a derivative.

The amount of the above-mentioned polyalcohols used is preferably in the range of 10/90 to 99.5 / 0.5 in the weight ratio of the carboxylic acid-containing polymer / polyalcohols. The weight ratio is more preferably in the range of 30/70 to 99/1, still more preferably 50/50 to 99/1, and most preferably in the range of 70/30 to 98/2.

As a method for producing the layer (Z1), for example, the method described in the pamphlet of International Publication WO2005 / 053954 can be used.

(Layer (Z2))
On the other hand, the layer (Z) contains a hydrolyzate 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, a vinyl alcohol-based polymer, and a carboxylic acid unit. It is composed of a polymer-containing composition containing a polymer (C1) and a carboxylic acid unit-containing polymer (C2), and the carboxylic acid unit-containing polymer (C1) comprises an acrylate unit, an acrylate unit, a methacrylic acid unit and A total of 30 mol% or more of at least one monomer unit selected from the methacrylate units is contained, and the carboxylic acid unit-containing polymer (C2) contains a maleic acid unit, a maleic acid ester unit, and a maleic acid. When at least one monomer unit selected from the salt units was contained in a total ratio of 30 mol% or more, there were cases where the barrier property was further improved. In the present specification, the layer (Z) having the characteristics is particularly referred to as a layer (Z2). Although the cause of the further improvement of the barrier property has not been clarified, there is an effect that the layer (Z2) itself has a gas barrier property and that the adhesion between the layer (Y) and the layer (Z2) is improved. It is thought that this is the reason.

Examples of the vinyl alcohol-based polymer contained in the layer (Z2) include polyvinyl alcohol-based resins exemplified as the material of the base material (X). At this time, the vinyl alcohol-based polymer used for producing the layer (Z2) is a group derived from at least one compound (L1) containing a metal atom to which at least one group selected from a halogen atom and an alkoxy group is bonded. Is preferably included. The compound (L1) undergoes an exchange reaction with the ester group contained in the vinyl ester-based polymer to bond with the polymer. In that case, the vinyl alcohol-based polymer contains a group derived from a compound (L1) containing a metal atom to which at least one selected from a halogen atom and an alkoxy group is bonded. The compound described for the compound (L) can be applied to the compound (L1), but the compound (L) and the compound (L1) may be the same or different.

The carboxylic acid unit-containing polymer (C1) contained in the layer (Z2) is a total of 30 at least one monomer unit selected from acrylic acid units, acrylate units, methacrylic acid units and methacrylic acid units. It is contained in a proportion of mol% or more (in all monomer units). That is, the carboxylic acid unit-containing polymer (C1) is a polymer obtained by copolymerizing at least one monomer selected from acrylic acid, acrylate, methacrylic acid and methacrylic acid at a ratio of 30 mol% or more. is there.

When the proportion of the monomer unit contained in the carboxylic acid unit-containing polymer (C1) is less than 30 mol%, the gas barrier property of the layer (Z2) is inferior. The content of the monomer unit contained in the carboxylic acid unit-containing polymer (C1) is preferably 50 mol% or more, and more preferably 70 mol% or more.

As the carboxylic acid unit-containing polymer (C1), polyacrylic acid, polymethacrylic acid, or a copolymer of acrylic acid and methacrylic acid, and a part of the carboxyl groups in these polymers are salts. A polymer or the like can be used. Further, a copolymer of acrylic acid and / or methacrylic acid and one or more vinyl compounds, and a polymer in which a part of the carboxyl group in these polymers is a salt can also be used. Vinyl compounds to be copolymerized include (meth) acrylates such as methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, butyl acrylate, and butyl methacrylate; vinyl formate and vinyl acetate. Vinyl esters such as; One or more vinyl compounds selected from olefins such as styrene, p-styrene sulfonic acid, propylene, and isobutylene can be used. Among these, it is preferable to use at least one selected from polyacrylic acid and a partially neutralized product of polyacrylic acid as the carboxylic acid unit-containing polymer (C1).

The carboxylic acid unit-containing polymer (C2) contained in the layer (Z2) contains at least one monomer unit selected from maleic acid units, maleic acid ester units, and maleate units in a total of 30 mol%. Included in the above ratio (in all monomer units). That is, the carboxylic acid unit-containing polymer (C2) is a polymer obtained by copolymerizing at least one monomer selected from maleic acid, maleic acid ester, and maleate salt at a total ratio of 30 mol% or more. .. In addition, maleic anhydride may be copolymerized instead of maleic acid. In this case, maleic anhydride becomes maleic acid in the process of forming the composition. Therefore, in this specification, the maleic anhydride unit is described as being included in the maleic acid unit and the maleate unit.

When the proportion of the monomer unit contained in the carboxylic acid unit-containing polymer (C2) is less than 30 mol%, the gas barrier property of the layer (Z2) is inferior. The content of the monomer unit contained in the carboxylic acid unit-containing polymer (C2) is preferably 50 mol% or more, more preferably 70 mol% or more.

As the carboxylic acid unit-containing polymer (C2), a copolymer of maleic acid and / or maleic acid ester and one or more vinyl compounds, and a part of the carboxyl groups in these polymers are salts. A polymer can be used. Examples of the vinyl compound to be copolymerized include olefins such as ethylene, propylene, isobutylene, styrene, and p-styrene sulfonic acid; methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, and butyl acrylate. , (Meta) acrylic acid esters such as butyl methacrylate; vinyl esters such as vinyl formate and vinyl acetate can be mentioned. Among these, it is preferable to use at least one selected from a partially neutralized product of the isobutylene-maleic acid copolymer and the isobutylene-maleic acid copolymer as the carboxylic acid unit-containing polymer (C2).

The content of the metal oxide (or the hydrolyzed condensate of the compound (L)) contained in the layer (Z2) at the time of drying, that is, the content in the components other than the solvent is in the range of 10 to 65% by weight. Is preferable. When the content is less than 10% by weight, the gas barrier property of the layer (Z2), particularly the oxygen barrier property in a high humidity atmosphere may decrease. Further, when the content exceeds 65% by weight, the gas barrier property of the layer (Z2) may be lowered, and the mechanical physical properties may be further lowered. The content is more preferably in the range of 20 to 55% by weight, still more preferably in the range of 25 to 45% by weight.

In the present invention, the content of the metal oxide (or the hydrolyzed condensate of the compound (L)) in the composition is the weight of the metal oxide obtained after removing the organic component of the composition by thermal decomposition. It is determined from the weight of the composition before thermal decomposition.

In the layer (Z2), the total content of the vinyl alcohol-based polymer, the carboxylic acid unit-containing polymer (C1) and (C2) at the time of drying is preferably in the range of 45% by weight to 80% by weight. , 55% by weight to 75% by weight, more preferably.

In the layer (Z2), the weight ratio of [carboxylic acid unit-containing polymer (C1)] / [carboxylic acid unit-containing polymer (C2)] is preferably in the range of 99/1 to 10/90. The layer (Z2) having a weight ratio in this range is excellent in gas barrier property. The weight ratio of [carboxylic acid unit-containing polymer (C1)] / [carboxylic acid unit-containing polymer (C2)] is more preferably in the range of 95/5 to 20/80, and even more preferably 90/10 to 10 It is in the range of 30/70.

In the layer (Z2), the weight ratio of [vinyl alcohol-based polymer] / [total of carboxylic acid unit-containing polymers (C1) and (C2)] is in the range of 99.5 / 0.5 to 70/30. Is preferable. In order to maintain the gas barrier property and the mechanical property, it is important that the polymer-containing composition contains the carboxylic acid unit-containing polymers (C1) and (C2). The weight ratio is preferably in the range of 99/1 to 80/20, more preferably in the range of 98/2 to 90/10.

Furthermore, the present inventors consider that the carboxylic acid unit-containing polymer (C1) is at least one selected from polyacrylic acid and partially neutralized products of polyacrylic acid, and the carboxylic acid unit-containing polymer (C2). It was found that is preferably at least one selected from the isobutylene-maleic acid copolymer and the partially neutralized product of the isobutylene-maleic acid copolymer. According to this combination, the gas barrier property of the layer (Z2) is particularly excellent. When this combination is used, the weight ratio of [carboxylic acid unit-containing polymer (C1)] / [carboxylic acid unit-containing polymer (C2)] is preferably in the range of 90/10 to 30/70. When it is in this range, the gas barrier property of the layer (Z2) is excellent. For the same reason, when the above combination is used, the weight ratio of [vinyl alcohol-based polymer] / [total of carboxylic acid unit-containing polymers (C1) and (C2)] is 98/2 to 90/10. It is preferably in the range of.

As a method for producing the layer (Z2), for example, the method described in JP-A-2005-307042 can be used.

In forming the layer (Z), the composition forming the layer (Z) may be dispersed in a solvent such as an organic solvent to make it liquid. Such a composition can be used as a coating agent (coating liquid composition) or a raw material for a film. The amount of solvent is determined according to the use of the composition. As the solvent, for example, the solvent exemplified in the description of the method for producing the layer (Z1) and the layer (Z2) can be used. Alternatively, depending on the physical properties of the composition forming the layer (Z), the layer (Z) can also be formed by melt molding such as extrusion coating. The layer (Z) is preferably a layer formed by directly applying a coating agent to the layer (Y).

The water contact angle of the surface of the layer (Z) is 10 to 70 °. The water contact angle can be measured using a contact angle meter described in Examples described later. When the water contact angle is less than 10 ° or more than 70 °, the surface characteristics of the layer (Y) and the layer (Z) are significantly different, so that the formation of the layer (Z) is difficult or even if it is formed. Sufficient interlayer adhesion cannot be obtained, and the object of the present invention cannot be achieved. The lower limit of the water contact angle is preferably 15 ° or more, more preferably 20 ° or more, and particularly preferably 30 ° or more. On the other hand, the upper limit of the water contact angle is preferably 65 ° or less, and more preferably 60 ° or less.

[Adhesive layer (H)]
In the multilayer structure of the present invention, the layer (Y) may be laminated so as to be in direct contact with the base material (X), but is arranged between the base material (X) and the layer (Y). The layer (Y) may be laminated on the base material (X) via the adhesive layer (H). According to this configuration, the adhesiveness between the base material (X) and the layer (Y) may be enhanced. Further, the adhesive layer (H) is arranged on the surface of the base material (X) and / or the layer (Z) of the multilayer structure to form a film (layer) other than the multilayer structure and other than the multilayer structure. It can be laminated with a member (for example, another layer such as a thermoplastic resin film layer or a paper layer). A multilayer structure in which a layer (X), a layer (Y), a layer (Z), and a layer (H) are laminated in this order is also one of the preferred embodiments of the present application. The adhesive layer (H) may be formed of an adhesive resin. In the adhesive layer (H) made of an adhesive resin, the surface of the base material (X) or the layer (Z) is treated with a known anchor coating agent, or the surface of the base material (X) or the layer (Z) is known. It can be formed by applying an adhesive. 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 base material (X) and the layer (Y) via the adhesive layer (H), a barrier property can be obtained when the vacuum packaging bag of the vacuum insulation 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 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) in this range, the barrier property and the deterioration of the appearance can be more effectively deteriorated when the vacuum packaging bag used for the vacuum insulation body of the present invention is manufactured or processed. It can be suppressed, and 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, and even more preferably in the range of 0.05 to 0.10 μm.

The multilayer structure of the present invention composed of a base material (X), a layer (Y), a layer (Z) or a base material (X), a layer (Y), a layer (Z) and an adhesive layer (H) has the multilayer structure. It can be laminated with other members other than the body (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. From the viewpoint that the multilayer structure itself has low thermal conductivity, it is preferable not to have a metal vapor deposition layer such as an aluminum vapor deposition layer.

According to the present invention, it is possible to obtain a multilayer structure satisfying the following performance.
(Performance 1) Oxygen permeability under the conditions of 40 ° C., 0% RH (carrier gas side) / 65% RH (oxygen supply side) 65% RH is 1.0 ml / (m ² · day · atm) or less. ..
(Performance 2) 40 ° C., 0% RH (carrier gas side) / 65% RH (oxygen supply side) 65 after holding for 5 minutes in a state of stretching 5% in one direction under the conditions of 23 ° C. and 50% RH. The oxygen permeability measured under the condition of% RH is 2.0 ml / (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 comprises a base material (X), a layer (Y), a layer (Z) or a base material (X), a layer (Y), a layer (Z) and an adhesive layer (H). It is composed of a multilayer structure and other members other than the multilayer structure (for example, other layers such as a thermoplastic resin film layer and a paper layer). 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. From the viewpoint that the vacuum package itself has low thermal conductivity, it is preferable not to have a metal vapor deposition layer such as an aluminum vapor deposition layer.

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. An anchor coat layer or an adhesive layer 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, "/" indicates that the two layers sandwiching the "/" are directly laminated (however, the adhesive layer (H) may be interposed). Further, "//" indicates that the two layers sandwiching "//" are indirectly laminated via an adhesive.
(1) Layer (Z) / Layer (Y) / Base material (X) // PO layer,
(2) Polyester layer // layer (Z) / layer (Y) / base material (X) // PO layer,
(3) Polyester layer // Base material (X) / Layer (Y) / Layer (Z) // PO layer,
(4) Polyamide layer // layer (Z) / layer (Y) / base material (X) // PO layer,
(5) Polyamide layer // Base material (X) / Layer (Y) / Layer (Z) // PO layer,
(6) PO layer // layer (Z) / layer (Y) / base material (X) // PO layer,
(7) Layer (Z) / Layer (Y) / Base material (X) / Layer (Y) / Layer (Z) // PO layer,
(8) Polyester layer // layer (Z) / layer (Y) / base material (X) / layer (Y) / layer (Z) // PO layer,
(9) Polyamide layer // layer (Z) / layer (Y) / base material (X) / layer (Y) / layer (Z) // PO layer,
(10) PO layer // layer (Z) / layer (Y) / base material (X) / layer (Y) / layer (Z) // PO layer,
(11) Polyester layer / layer (Z) / layer (Y) // base material (X) // PO layer,
(12) Polyamide layer / layer (Z) / layer (Y) // base material (X) // PO layer,
(13) PO layer / layer (Z) / layer (Y) // base material (X) // PO layer,
(14) Polyester layer / layer (Y) // layer (Z) / layer (Y) / base material (X) // PO layer,
(15) Polyamide layer / layer (Y) // layer (Z) / layer (Y) / base material (X) // PO layer,
(16) PO layer / layer (Y) // layer (Z) / layer (Y) / base material (X) // PO layer,
(17) Polyester layer / layer (Y) // layer (Z) / layer (Y) / base material (X) / layer (Y) // layer (Z) / PO layer,
(18) Polyamide layer / layer (Y) // layer (Z) / layer (Y) / base material (X) / layer (Y) / layer (Z) // PO layer,
(19) PO layer / layer (Y) // layer (Z) / layer (Y) / base material (X) / layer (Y) / layer (Z) // PO layer,
(20) Polyamide layer // Polyester layer / Layer (Y) // Layer (Z) / Layer (Y) / Base material (X) // PO layer,
(21) PO layer // polyester layer / layer (Y) // layer (Z) / layer (Y) / base material (X) // PO layer,
(22) Polyamide layer // Polyester layer / Aluminum vapor deposition layer // Layer (Z) / Layer (Y) / Base material (X) // PO layer,
(23) PO layer // polyester layer / aluminum vapor deposition layer // layer (Z) / layer (Y) / base material (X) // PO layer,
(24) Polyamide layer // base material (X) / layer (Y) / layer (Z) // layer (Z) / layer (Y) / base material (X) // PO layer,
(25) PO layer // base material (X) / layer (Y) / layer (Z) // layer (Z) / layer (Y) / base material (X) // PO layer.
Among these, in order to obtain a vacuum insulating body in which the original barrier property of the vacuum packaging bag is maintained at a high level and the vacuum packaging bag itself has low thermal conductivity even when subjected to physical stress, the above layer The configurations (1), (2), (4), (6) to (25) are particularly preferable. Further, in the above layer configurations (1), (2), (4), (6) to (21), (24), and (25), transparency can be obtained, and for example, the internal state is confirmed by color. It is even more preferable when it is necessary to visually recognize the contents containing the indicator substance which can be used. A vacuum insulation body in which the vacuum packaging bag is transparent and has an indicator substance inside is also one of the preferred embodiments of the present invention.

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, 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]
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 fully 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 upper limit of the thermal conductivity one day after the production of the vacuum heat insulating body is preferably 3.0 mW / (m · K), more preferably 2.5 mW / (m · K). On the other hand, as the lower limit of the thermal conductivity one day after the preparation, 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 insulation body of the present invention can maintain the insulation performance for a long period of time. As for the heat insulating performance, it is preferable that the thermal conductivity (Q) 90 days after the preparation in the measurement of the thermal conductivity of the vacuum heat insulating body (7) described later is 4.8 mW / (m · K) or less, preferably 4.5 mW. It is more preferably less than / (m · K). The thermal conductivity (Q) 90 days after preparation is usually 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 in which a heat seal layer is 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 to produce a vacuum packaging bag in which the core material is arranged. 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 a sufficient useful life as a heat insulating material can be achieved. 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 insulating applications such as tea servers and jar pots that require heat insulation.

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. Each measurement and evaluation in Examples and Comparative Examples was carried out by the following methods (1) to (7).

(1) Appearance of the multi-layer structure The appearance of the obtained multi-layer structure was visually evaluated as follows.
A: It was colorless and transparent, uniform, and had an extremely good appearance.
B: It was opaque and uniform, and had a very good appearance.
C: Significant wrinkles and dimensional changes were observed, and it was judged that it could not be put to practical use, and measurement and evaluation were discontinued.

(2) Average Thickness of Inorganic Oxide Deposited Layer After cutting a multilayer sheet with a microtome to expose a cross section, this cross section is reflected by a scanning electron microscope (“ZEISS ULTRA 55” manufactured by SI Nanotechnology). The average thickness of the inorganic oxide vapor deposition layer was measured by measurement using an electron detector.

(3) Measurement of water contact angle The water contact angle was measured using a contact angle meter. The measurement conditions were as follows.
Equipment: DM-700 manufactured by Kyowa Interface Science Co., Ltd.
Liquid volume: 1.0 μL
Waiting time after dripping: 1.0 second Analysis method: θ / 2 method

(4) Oxygen permeability (Os) of the multilayer structure
The oxygen permeability was measured using an oxygen permeation measuring device (“MOCON OX-TRAN2 / 20” manufactured by Modern Control Co., Ltd.). Specifically, the multilayer structure is set so that the layer (Y or Z) faces the oxygen supply side and the base material (X) faces the carrier gas side, the temperature is 40 ° C., and the humidity on the oxygen supply side is 65. % RH, humidity 0% RH carrier gas side, the oxygen pressure is 1 atm, the oxygen permeability carrier gas pressure under the conditions of 1 atm ^{(unit: ml / (m 2 · day} · atm)) was measured. As the carrier gas, nitrogen gas containing 2% by volume of hydrogen gas was used.

(5) Oxygen permeability (Of) of the multilayer structure after stretching and holding by 5%
The produced multilayer structure was cut into a size of 21 cm × 30 cm, left to stand for 24 hours or more under the conditions of 23 ° C. and 50% RH, and then stretched by 5% in one direction corresponding to the major axis direction under the same conditions. By holding the stretched state for 5 minutes, a stretched multilayer structure was obtained. The oxygen permeability of the stretched multilayer structure was measured in the same manner as in (4) above.

(6) Oxygen permeability (Og) of the multilayer structure after the transportation test
The obtained vacuum insulation body was placed in a cardboard box (67 × 61 × 45 cm) by folding the end portion of the vacuum packaging bag along the shape of the core material. A transport test was conducted in which cardboard boxes were loaded onto trucks and made 10 round trips between Okayama Prefecture and Tokyo. A 10 × 10 cm multi-layer structure sample for measurement was cut out from the vacuum insulation body after the transportation test so as to include the folding corners, and the oxygen permeability of the sample was measured in the same manner as in (4) above.

(7) Thermal Conductivity of Vacuum Insulation After storing the obtained vacuum insulation at 100 ° C for a certain period of time, use a thermal conductivity measuring device (FOX314 manufactured by Eiko Seiki Co., Ltd.) to place one side of the vacuum insulation. The thermal conductivity of the vacuum insulator was measured by setting the temperature to 38 ° C. and the temperature on the other surface side to 12 ° C. The measurement was performed 1, 30, and 90 days after the vacuum insulation was prepared.

[Example 1]
As the base material (X), an ethylene-vinyl alcohol copolymer (EVOH) film (thickness 12 μm) stretched biaxially in a size of 3 times (MD) × 3 times (TD) was prepared. The ethylene content of EVOH used for the base material (X) was 32.0 mol%, and the saponification degree was 100%. A layer (Y) made of aluminum oxide is formed on one surface of the base material (X) by melting and evaporating aluminum while introducing oxygen using a batch type vapor deposition facility (“EWA-105” manufactured by Nippon Vacuum Technology Co., Ltd.). ) Was formed.

The layer (Z) was created by the method shown below. First, polyacrylic acid (PAA) having a number average molecular weight of 150,000 is dissolved in distilled water, and then aqueous ammonia is added to neutralize 1.5 mol% of the carboxyl groups of polyacrylic acid to solidify the solid in the aqueous solution. An aqueous polyacrylic acid solution having a component concentration of 10% by weight was obtained.

Next, 68.4 parts by weight of tetramethoxysilane (TMS) was dissolved in 82.0 parts by weight of methanol, and then 13.6 parts by weight of γ-glycidoxypropyltrimethoxysilane was dissolved, followed by distilled water. A sol was prepared by adding 13 parts by weight and 12.7 parts by weight of 0.1 N (0.1 specified) hydrochloric acid, and the hydrolysis and condensation reaction was carried out at 10 ° C. for 1 hour with stirring. The obtained sol was diluted with 185 parts by weight of distilled water and then rapidly added to 634 parts by weight of the above 10% by weight polyacrylic acid aqueous solution under stirring to obtain a solution (S-1).

The solution (S-1) is coated on the layer (Y) of the base material (X) / layer (Y) with a bar coater so that the thickness after drying becomes 0.5 μm, and then 5 at 80 ° C. It was dried for 1 minute, then aged at 50 ° C. for 3 days (72 hours), and further heat-treated at 160 ° C. for 5 minutes in dry air.

Next, calcium acetate was dissolved in distilled water so that the concentration was 10% by weight, and the aqueous solution was kept warm at 80 ° C. Then, the laminate obtained above was immersed in this aqueous solution for about 20 seconds. After immersion, the laminate is taken out, the surface of the laminate is washed with distilled water adjusted to 80 ° C., and then dried at 80 ° C. for 5 minutes to obtain a base material (X) / layer (Y) /. A multilayer structure composed of the layer (Z) was obtained.

C = O stretching vibration contained in the layer (Z) of the above multilayer structure in ATR (total reflection measurement) mode using a Fourier transform infrared spectrophotometer (manufactured by Shimadzu Corporation, "8200PC"). The peak of was observed. The peak attributable to the C = O expansion and contraction vibration of the carboxyl group of the carboxylic acid-containing polymer before ionization was observed in the range of 1,600 cm ^{-1 to} 1,850 cm ^-1 , and the C = O of the carboxyl group after ionization. O stretching vibration was observed in the range of 1,500 cm ^{-1 to} 1,600 cm ^-1 . Then, the ratio was calculated from the maximum absorbance in each range, and the degree of ionization was determined using the ratio and the calibration curve prepared in advance by the following method. As a result, it was found that 60 mol% of the carboxyl groups were neutralized with calcium ions.

(Creation of calibration curve)
Polyacrylic acid having a number average molecular weight of 150,000 was dissolved in distilled water, and a predetermined amount of sodium hydroxide was used to neutralize the carboxyl group. An aqueous solution of the obtained neutralized polyacrylic acid is placed on the layer (Y) of the base material (X) / layer (Y) to the same thickness as the layer (Z) whose degree of ionization is to be measured. It was coated and dried. In this way, 11 types of standard samples in which the degree of neutralization of the carboxyl group differs by 10 mol% between 0 and 100 mol% [Laminated body (layer / layer (Y) / composed of neutralized product of polyacrylic acid / Base material (X))] was prepared. The infrared absorption spectra of these samples were measured in ATR (total reflection measurement) mode using a Fourier transform infrared spectrophotometer (manufactured by Shimadzu Corporation, 8200 PC). Then, two peaks corresponding to C = O expansion and contraction vibration contained in the layer composed of the neutralized product of polyacrylic acid, that is, the peak observed in the range of 1,600 cm ^{-1 to} 1,850 cm ^-1 , and 1, for a peak observed in the range of 500cm ^-1 ~1,600cm ^-1, and calculating the ratio of the maximum absorbance value. Then, a calibration curve was prepared using the calculated ratio and the degree of ionization of each standard sample.

The obtained multilayer structure was evaluated by the methods (1) to (5) above.

[Example 2]
As the base material (X), an ethylene-vinyl alcohol copolymer film (thickness 15 μm) stretched biaxially in a size of 3 times (MD) × 3 times (TD) was used, and the layers were multilayered in the same manner as in Example 1. A structure was prepared and evaluated in the same manner as in Example 1.

[Example 3]
As the base material (X), an ethylene-vinyl alcohol copolymer film (thickness 12 μm) stretched biaxially in a size of 3 times (MD) × 3 times (TD) was prepared. A layer (Y) made of silicon oxide is formed on one surface of the base material (X) by melting and evaporating silicon oxide on the film using a batch type vapor deposition facility (“EWA-105” manufactured by Nippon Vacuum Technology Co., Ltd.). Was formed.
A multilayer structure was obtained by preparing a layer (Z) of the obtained base material (X) / layer (Y) in the same manner as in Example 1. The evaluation was carried out in the same manner as in Example 1.

[Example 4]
As the base material (X), an ethylene-vinyl alcohol copolymer film (thickness 15 μm) stretched biaxially in a size of 3 times (MD) × 3 times (TD) was used, and the layers were multilayered in the same manner as in Example 3. A structure was prepared and evaluated in the same manner as in Example 1.

[Example 5]
A multilayer structure was prepared in the same manner as in Example 1 except that the average thickness of the layer (Y) was changed, and the evaluation was performed in the same manner as in Example 1.

[Example 6]
A multilayer structure was prepared in the same manner as in Example 3 except that the average thickness of the layer (Y) was changed, and the evaluation was performed in the same manner as in Example 1.

[Example 7]
A multilayer structure was prepared in the same manner as in Example 1 except that the layer (Z) was prepared by the method shown below, and its evaluation was performed in the same manner as in Example 1.
PVA-110H (saponification degree 98 mol% or more), which is a polyvinyl alcohol resin manufactured by Kuraray Co., Ltd., was put into distilled water and stirred for 1 hour or more while heating at 90 ° C. to obtain an aqueous solution (S-2).

The solution (S-2) is coated on the layer (Y) of the base material (X) / layer (Y) with a bar coater so that the thickness after drying becomes 0.5 μm, and then the solution (S-2) is coated at 100 ° C. for 3 minutes. It was dried to create a multilayer structure.

[Example 8]
A multilayer structure was prepared in the same manner as in Example 7 except that the layer (Y) was silicon oxide, and the evaluation was carried out in the same manner as in Example 1.

[Example 9]
A multilayer structure was prepared in the same manner as in Example 1 except that the layer (Z) was prepared by the method shown below, and its evaluation was performed in the same manner as in Example 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. After cooling, 15 g of water was added to the polymerization solution to dilute the solution, and the mixture was filtered using "Spectra / Por" (registered trademark) manufactured by Spectrum Laboratories, which is a cellulose film. After distilling off the water in the filtrate, it was vacuum dried at 50 ° C. for 24 hours to obtain poly (vinyl phosphonic acid). As a result of GPC analysis, the number average molecular weight of the polymer 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 an aqueous solution (S-3).

The solution (S-3) is coated on the layer (Y) of the base material (X) / layer (Y) with a bar coater so that the thickness after drying becomes 0.5 μm, and then the solution (S-3) is coated at 100 ° C. for 3 minutes. It was dried to create a multilayer structure.

[Example 10]
A multilayer structure was prepared in the same manner as in Example 1 except that the layer (Z) was prepared by the method shown below, and its evaluation was performed in the same manner as in Example 1.

A methanol solution containing an ethylene-vinyl acetate copolymer having a degree of polymerization of 500 (ethylene denaturation rate of 8 mol%) at a content of 38% by weight was prepared. To 400 parts by weight of this methanol solution, 13.3 parts by weight of tetramethoxysilane and 84.1 parts by weight of methanol were added, and the mixture was stirred for about 10 minutes so that the solution became uniform. Then, the solution was sampled and the amount of water contained in the solution was measured. Then, water was added so that the amount of water contained in the solution was 5,000 ppm.

To the obtained solution, 20.9 parts by weight of a methanol solution of sodium hydroxide (sodium hydroxide 10%) was added, and a saponification reaction was carried out at 40 ° C. The solution gelled about 10 minutes after the addition of the methanol solution of sodium hydroxide. After gelation, the product was left at a temperature of 40 ° C. for another 20 minutes to proceed with the saponification reaction. After the saponification reaction, the obtained gel was pulverized, 1500 parts by weight of methanol was added thereto, and the temperature of the system was maintained at 40 ° C. and the mixture was stirred for 1 hour. After stirring, methanol was removed by filtration, and 1,500 parts by weight of methanol was added again. Next, the temperature of the system was maintained at 40 ° C. and the mixture was stirred for 1 hour. Methanol was then removed from the product by filtration and the product was dried over 20 hours in a hot air dryer adjusted to 65 ° C. In this way, a vinyl alcohol-based polymer was obtained. When this vinyl alcohol polymer and its composition were analyzed, the residual ratio of the acyl group derived from the vinyl carboxylate unit in the ethylene-vinyl acetate copolymer was 1.0 mol%, and the residual sodium acetate amount was 1. It was 0.0% by weight. The amount of Si atoms bonded to the vinyl alcohol polymer was 5.0 mol with respect to 100 mol of the acyl group derived from the vinyl carboxylate unit before saponification.

50.0 parts by weight of this vinyl alcohol polymer was dissolved in distilled water to prepare an aqueous solution having a solid content concentration of 10% by weight. Separately from this, an aqueous solution of polyacrylic acid (PSA-HL415 manufactured by Nippon Shokubai Co., Ltd., number average molecular weight 10,000) was adjusted so that the solid content concentration was 10% by weight. Further, an isobutylene-maleic anhydride alternating copolymer (Isoban 600 manufactured by Kuraray Co., Ltd .: content of 50 mol% of maleic anhydride unit) contains 0.75 part mol of ammonia with respect to the carboxyl group of maleic anhydride. It was dissolved in aqueous ammonia to obtain an aqueous solution of an isobutylene-maleic anhydride alternating copolymer salt. At this time, it was dissolved in aqueous ammonia so that the concentration of the isobutylene-maleic acid alternating copolymer salt was 10% by weight.

500.0 parts by weight of the aqueous solution of the vinyl alcohol polymer, 16.0 parts by weight of the aqueous solution of the polyacrylic acid, and 16.0 parts by weight of the aqueous solution of the isobutylene-maleic acid alternating copolymer salt are mixed and vinyl alcohol-based. Adjust the solution (S-4) in which the weight ratio of the polymer (ethylene-modified PVA / polyacrylic acid (PAA) / isobutylene-maleic acid alternating copolymer salt (P (MA / IB)) is 94/3/3. did.

Next, 72.3 parts by weight of tetramethoxysilane was dissolved in 72.3 parts by weight of methanol, and then 4.8 parts by weight of distilled water and 11.9 parts by weight of 0.1N (0.1 specified) -hydrochloric acid were added. The sol was prepared by carrying out the reaction at 40 ° C. for 1 hour with stirring. The obtained sol was diluted with 124.3 parts by weight of distilled water, and then the above solution (S-4) was quickly added while stirring the sol to prepare the solution (S-5). After the adjustment, the solution (S-5) was left to stand in an atmosphere of 25 ° C. for 1 hour.

The solution (S-5) is coated on the layer (Y) of the base material (X) / layer (Y) with a bar coater so that the thickness after drying becomes 0.5 μm, and dried at 80 ° C. for 5 minutes. After that, heat treatment was further performed at 160 ° C. for 5 minutes to prepare a multilayer structure.

[Example 11]
A multilayer structure was prepared in the same manner as in Example 10 except that the layer (Y) was silicon oxide, and the evaluation was carried out in the same manner as in Example 1.

[Example 12]
The same method as in Example 3 except that an ethylene-vinyl alcohol copolymer film (thickness 12 μm) biaxially stretched 3.5 times (MD) × 4 times (TD) was used as the base material (X). A multilayer structure was prepared in 1 and evaluated in the same manner as in Example 1.

[Example 13]
The same method as in Example 3 except that an ethylene-vinyl alcohol copolymer film (thickness 12 μm) biaxially stretched 2.5 times (MD) × 3 times (TD) was used as the base material (X). A multilayer structure was prepared in 1 and evaluated in the same manner as in Example 1.

[Comparative Example 1]
The same method as in Example 1 except that an unstretched ethylene-vinyl alcohol copolymer film (“EVAL® EF-F” manufactured by Kuraray Co., Ltd., thickness 12 μm) was used as the base material (X). A multilayer structure was prepared and evaluated in the same manner as in Example 1. However, the water contact angle could not be measured due to the poor surface condition of the multilayer structure. In addition, the oxygen permeability was not measured due to poor appearance.

[Comparative Example 2]
The same method as in Example 2 except that an unstretched ethylene-vinyl alcohol copolymer film (“EVAL (registered trademark) EF-F” manufactured by Kuraray Co., Ltd., thickness 12 μm) was used as the base material (X). A multilayer structure was prepared and evaluated in the same manner as in Example 1. However, the water contact angle could not be measured due to the poor surface condition of the multilayer structure. In addition, the oxygen permeability was not measured due to poor appearance.

[Comparative Example 3]
A multilayer structure was prepared in the same manner as in Example 1 except that a biaxially stretched polyester film (“Lumilar (registered trademark)” manufactured by Toray Industries, Inc., thickness 12 μm) was used as the base material (X). The evaluation was performed in the same manner as in Example 1.

[Comparative Example 4]
A multilayer structure was prepared in the same manner as in Example 3 except that a biaxially stretched polyester film (“Lumilar (registered trademark)” manufactured by Toray Industries, Inc., thickness 12 μm) was used as the base material (X). The evaluation was performed in the same manner as in Example 1.

[Comparative Example 5]
A multilayer structure was prepared in the same manner as in Example 1 except that the layer (Y) was aluminum, and its evaluation was carried out in the same manner as in Example 1. The layer (Y) was formed on one surface of the base material (X) by melting and evaporating aluminum using a batch type vapor deposition facility (“EWA-105” manufactured by Nippon Vacuum Technology Co., Ltd.).

[Comparative Example 6]
A multilayer structure was prepared in the same manner as in Comparative Example 5 except that the thickness of the layer (Y) was different, and the evaluation was carried out in the same manner as in Example 1.

[Comparative Example 7]
A multilayer structure in which a layer (Y) was formed on one surface of the base material (X) by the same method as in Example 1 was designated as Comparative Example 7, and the evaluation was performed by the same method as in Example 1.

[Comparative Example 8]
A multilayer structure in which a layer (Y) was formed on one surface of the base material (X) by the same method as in Example 2 was designated as Comparative Example 8, and the evaluation was performed by the same method as in Example 1.

[Comparative Example 9]
A multilayer structure was prepared in the same manner as in Example 1 except that the layer (Z) was prepared by the method shown below, and its evaluation was performed in the same manner as in Example 1.
On the layer (Y) of the base material (X) / layer (Y), a polyethylene resin (density; 0.917 g / cm3, melt flow rate; 8 g / 10 minutes) is placed on the adhesive layer so as to have a thickness of 5 μm. It was extruded and coated on top at 295 ° C.

[Comparative Example 10]
A multilayer structure was prepared in the same manner as in Example 3 except that the layer (Z) was prepared by the method shown below, and its evaluation was performed in the same manner as in Example 1.
On the layer (Y) of the base material (X) / layer (Y), a polyethylene resin (density; 0.917 g / cm3, melt flow rate; 8 g / 10 minutes) is placed on the adhesive layer so as to have a thickness of 5 μm. It was extruded and coated on top at 295 ° C.

[Comparative Example 11]
Similar to Example 3 except that an ethylene-vinyl alcohol copolymer film (thickness 12 μm) biaxially stretched 2.5 times (MD) × 2.5 times (TD) was used as the base material (X). A multilayer structure was prepared by the method of the above, and its evaluation was performed by the same method as in Example 1.

[Comparative Example 12]
As the base material (X), an ethylene-vinyl alcohol copolymer film (thickness 12 μm) stretched biaxially by 2 times (MD) × 4 times (TD) was used, and the layers were multilayered in the same manner as in Example 3. A structure was prepared and evaluated in the same manner as in Example 1.

[Comparative Example 13]
An attempt was made to form an ethylene-vinyl alcohol copolymer film (thickness 12 μm) biaxially stretched 4 times (MD) × 4 times (TD) as the base material (X), but the film was broken during stretching and stretched. I couldn't get the film.

Tables 1 and 2 show the manufacturing conditions of the multilayer structure and the evaluation results of the multilayer structure for Examples 1 to 13 and Comparative Examples 1 to 13.

[Example 14]
Using the multilayer structure obtained in Example 1, a laminate (a) composed of "OPA / multilayer structure / CPP" was prepared by the following method. Stretched polyamide film with a thickness of 15 μm (“Emblem (registered trademark) ON-BC”, (OPA) manufactured by Unitika Co., Ltd.) and unstretched polypropylene film with a thickness of 60 μm (“CP RXC-18” manufactured by Mitsui Chemicals Tohcello Corporation , (CPP)), a two-component adhesive (manufactured by Mitsui Chemicals, Inc., "A-520" and "A-50") is applied to each side, and OPA layer / adhesive layer / multilayer structure / A laminated body (a) was obtained by laminating a CPP film, an OPA film, and a multilayer structure so as to have an adhesive layer / CPP layer. The multilayer structure was laminated so that the side having the layer (Y) was adjacent to the adhesive layer adjacent to OPA.

The obtained laminated body was cut to obtain two covering materials having a size of 20 cm × 25 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 vacuum packaging bag which is a three-sided bag.

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 insulating body was produced 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 insulation was evaluated by the methods (6) and (7) above.

[Examples 15 to 26 and Comparative Examples 14 to 23]
Using the multilayer structures obtained in Examples 2 to 13 and Comparative Examples 3 to 12, a vacuum heat insulating body was prepared in the same manner as in Example 14, and evaluated in the same manner as in Example 14. However, the evaluation of the vacuum insulation bodies of Comparative Examples 20 and 21 was discontinued because peeling was observed immediately after the preparation.

[Example 27]
Using the multilayer structure obtained in Example 1, a laminate (b) composed of "OPA / multilayer structure / multilayer structure / CPP" was prepared by the following method. The two-component adhesive is applied to each of the CPP, the OPA, and one side of the multilayer structure, and the OPA layer / adhesive layer / multilayer structure / adhesive layer / multilayer structure / adhesive layer / CPP. A laminated body was obtained by laminating a CPP film, an OPA film, and a multilayer structure so as to form a layer. The multilayer structure was laminated so that the sides having both layers (Y) were adjacent to each other with the adhesive layer interposed therebetween.

Using the obtained laminated body, a vacuum packaging bag and a vacuum heat insulating body were produced in the same manner as in Example 14, and the obtained vacuum heat insulating body was evaluated by the methods (6) and (7) above.

[Example 28]
Using the multilayer structure obtained in Example 3, a vacuum heat insulating body was prepared and evaluated in the same manner as in Example 27.

Tables 3 and 4 show the configurations of the vacuum packaging bags and the evaluation results of the vacuum insulators for Examples 14 to 28 and Comparative Examples 14 to 23.

The vacuum insulation bodies obtained in Examples 14 to 28 have a smaller change in thermal conductivity with time as compared with the vacuum insulation bodies obtained in Comparative Examples 14 to 23, and the vacuum packaging bag originally has a high level of barrier property. It can be seen that it is maintained at.

Further, as shown in Comparative Examples 16 and 17, the vacuum heat insulating body having the metal vapor deposition layer has a relatively high thermal conductivity immediately after the vacuum heat insulating body is formed, and the heat conduction via the vacuum packaging bag is relatively high. You can see that it is big.

[Example 29]
Using the multilayer structure obtained in Example 1, a laminate (c) composed of "OPA / VM-PET / multilayer structure / CPP" was prepared by the following method. The two-component adhesive is applied to each of one side of the biaxially stretched polyester film (VM-PET) on which the CPP, the OPA, and the aluminum vapor deposition layer are formed, and the OPA layer / adhesive layer / VM-PET is applied. A laminated body was obtained by laminating a CPP film, an OPA film, a VM-PET film, and a multilayer structure so as to have a structure of a layer / adhesive layer / multilayer structure / adhesive layer / CPP layer. 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 with the side having the layer (Y) as the VM-PET side.

Using the obtained laminated body, a vacuum packaging bag and a vacuum heat insulating body were produced in the same manner as in Example 14, and the obtained vacuum heat insulating body was evaluated by the methods (6) and (7) above.

[Example 30 and Comparative Examples 24 and 25]
Using the multilayer structures obtained in Example 3 and Comparative Examples 5 and 6, a vacuum heat insulating body was prepared and evaluated in the same manner as in Example 29.

Table 5 shows the configuration of the vacuum packaging bag and the evaluation results of the vacuum insulation body for Examples 29 and 30 and Comparative Examples 24 and 25.

As described above, the multilayer structure of the present invention and the vacuum packaging bag containing the multilayer structure are maintained at a high level of the barrier property originally possessed by the vacuum packaging bag even when subjected to physical stress, and the vacuum packaging bag is vacuum-packed. The packaging bag itself can have low thermal conductivity. Therefore, the vacuum heat insulating body produced by using the vacuum packaging bag can maintain excellent heat insulating performance for a long period of time.

Claims (9)

On at least one surface of the base material (X) made of a biaxially stretched polyvinyl alcohol-based film, a thin-film deposition layer (Y) made of an inorganic oxide and a layer (Z) containing an organic polymer are formed on the base material (X) /. It has a structure in which the layer (Y) / the layer (Z) is laminated in this order, the layer (Y) and the layer (Z) are adjacent to each other, and the water contact angle on the surface of the layer (Z) is 10 to 10. It is 70 °, and the draw ratio of the base material (X) is 2.5 times or more and 4.5 times or less in the vertical direction (MD direction), 2.5 times or more and 4.5 times or less in the horizontal direction (TD direction), and A multilayer structure having a surface stretch ratio of 7 times or more and 15 times or less. The multilayer structure according to claim 1, wherein the base material (X) is a film made of an ethylene-vinyl alcohol copolymer having an ethylene 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 layer (Y) is a vapor-deposited layer containing at least one inorganic oxide selected from the group consisting of aluminum oxide and silicon oxide. The item according to any one of claims 1 to 3, wherein the organic polymer contained in the layer (Z) has at least one functional group selected from the group consisting of a functional group containing a hydroxyl group, a carboxylic acid group and a phosphorus atom. The multi-layer structure described. Any one of claims 1 to 4, wherein the layer (Z) contains 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. The multilayer structure described in. Claims 1 to 5, wherein the oxygen permeability under the conditions of 40 ° C. and 0% RH (carrier gas side) / 65% RH (oxygen supply side) is 1.0 ml / (m ² · day · atm) or less. The multilayer structure according to any one item. Measured under the conditions of 40 ° C., 0% RH (carrier gas side) / 65% RH (oxygen supply side) after holding for 5 minutes in a state of stretching 5% in one direction under the conditions of 23 ° C. and 50% RH. The multilayer structure according to any one of claims 1 to 6, wherein the oxygen permeability is 2.0 ml / (m ² · day · atm) or less. 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 7. bag. A vacuum insulating body comprising the vacuum packaging bag according to claim 8 and a core material arranged inside surrounded by the vacuum packaging bag, the inside of which is depressurized.