JP7273475B2 - LAMINATED BODY AND SEALING MEMBER USING THE SAME - Google Patents

Description

TECHNICAL FIELD The present invention relates to a laminate having excellent oxygen and water vapor barrier properties, laminate strength, bending resistance and tensile resistance, and a sealing member using the same.

Various packaging materials have been used to package various things such as food and drink, pharmaceuticals, and daily necessities. Needed. Aluminum foils having excellent gas barrier properties are used as packaging materials for retort food, insulation materials for refrigerators, and outer layer packaging materials for vacuum insulation materials such as insulation panels for houses. However, since packaging materials using aluminum foil are prone to pinholes, it is difficult to handle aluminum foil, and the applications are limited.

In order to solve these problems, a film obtained by depositing aluminum or aluminum oxide on a thermoplastic film such as a polyester film using a physical vapor deposition method such as a vacuum deposition method is used. However, aluminum-deposited films have insufficient gas barrier performance for boiled/retort food applications, and the vapor-deposited aluminum layer disappears during boil/retort sterilization, resulting in a significant deterioration in gas barrier performance, making them unusable. .

As a gas barrier film for boiled and retort food applications, a gas barrier film is disclosed in which a vapor deposition layer composed of an inorganic oxide or inorganic nitride and a specific resin layer are laminated on at least one side of a plastic film. (Patent document 1).

In order to improve the alkali boiling resistance and acetic acid retort resistance of the aluminum vapor deposition film and suppress changes in the appearance of the aluminum vapor deposition layer, the substrate (a), the metal vapor deposition layer (b) and the protective layer (c) are arranged in this order. and the protective layer (c) contains a specific dimer acid-based polyamide resin, but the gas barrier performance was not sufficient (Patent Document 2).

On the other hand, the thermal conductivity of aluminum is about 200 W/m K, which is about 0.14 W/m K, which is the thermal conductivity of polyethylene terephthalate, which is a typical packaging material, and about 0 W/m K, which is the thermal conductivity of air. Since it is larger than 0.02 W/m·K, heat bridges occur where heat is transferred through the aluminum foil portion of the heat insulating material laminated with aluminum foil, and the heat insulating performance of the vacuum heat insulating material is greatly reduced. was there. In addition, films for vacuum insulation materials are required to have excellent gas barrier performance in order to prevent gas (air) from entering from the outside and to maintain a vacuum state for a long period of time. Furthermore, in recent years, the fins around the vacuum insulation material (welded and sealed parts) have lower insulation performance than the part containing the core material, and the fins are bent to maintain the overall insulation performance. Also, the vacuum insulation material itself is deformed according to the shape of the storage space when it is used in a place with a complicated shape (for example, an arc shape or a right angle shape). In view of the above, it is also required that the film for vacuum insulation material does not deteriorate in gas barrier performance when it is bent or deformed. Similarly, packaging materials for retort foods such as retort pouches are also required to maintain gas barrier performance when the package is bent or deformed during molding.

In order to solve this problem, gas barrier films are disclosed in which a deposition layer composed of an inorganic oxide or an inorganic nitride and a specific resin layer are laminated (Patent Documents 3 and 4).

JP 2010-131756 A JP 2012-210744 A Japanese Patent Application Laid-Open No. 2005-132004 JP 2013-202822 A

In any of the patent documents, a vapor deposition layer composed of a metal or metal compound layer and a specific resin layer are laminated. For example, in Patent Document 4, a gas barrier layer is provided as a first layer on a substrate, and a gas barrier coating layer containing a water-soluble polymer and a silicon compound is further provided as a second layer to form a gas barrier laminated film. However, none of the patent documents considers the state of the surface layer of the metal or metal compound layer that exhibits barrier properties and the bonding state of the resin layer that is in contact with the surface layer. In addition, since the resin layer does not contain polysiloxane having a linear structure, there are problems such as peeling of the resin layer and insufficient flex resistance and tensile resistance.

In view of this problem, in the present invention, by clarifying the preferable state of the laminate, it has excellent oxygen and water vapor barrier performance, laminate strength, bending resistance, and tensile resistance It is possible to stabilize the laminate. The purpose is to provide

The laminate of the present invention is a laminate having, on at least one side of a base film, an inorganic layer and a protective layer in this order from the base film side, wherein the inorganic layer is a single layer (composition within the inorganic layer). The inorganic layer contains a metal at least on the surface in contact with the base film, contains a metal oxide at least on the surface in contact with the protective layer, and the protective layer is a vinyl-based layer The laminate is characterized by containing a resin and linear polysiloxane having a linear structure of pentamer or higher .

According to the present invention, it is possible to provide a laminate having excellent oxygen and water vapor barrier properties, lamination strength, bending resistance and tensile resistance.

The laminate of the present invention will be described in more detail below.

The laminate of the present invention is a laminate having, on at least one side of a base film, an inorganic layer and a protective layer in this order from the base film side, wherein the inorganic layer is a single layer (composition within the inorganic layer). The inorganic layer contains a metal at least on the surface in contact with the base film, contains a metal oxide at least on the surface in contact with the protective layer, and the protective layer is a vinyl-based layer The laminate is characterized by containing a resin and linear polysiloxane having a linear structure of pentamer or higher .

In the laminate of the present invention, the protective layer in contact with the inorganic layer contains linear polysiloxane having a linear structure of pentamers or more as a specific silicon compound together with the vinyl resin, so that the protective layer has a dense and tough structure. Furthermore, the inorganic layer contains a metal on at least the surface in contact with the base film and contains a metal oxide on at least the surface in contact with the protective layer, whereby high adhesion to the protective layer having a dense and tough structure can be obtained. As a result, it is presumed that high flex resistance and tensile resistance can be expressed.

[Base film]
The resin constituting the base film according to the present invention is not particularly limited. , polybutene, polymethylpentene and other polyolefin resins, cyclic polyolefin resins, polyamide resins, polyimide resins, polyether resins, polyester amide resins, polyether ester resins, acrylic resins, polyurethane resins, polycarbonates system resin, polyvinyl chloride system resin, or the like. Among them, a polyester film is preferable from the viewpoint of adhesion to the inorganic compound layer and handling. The base film may be unstretched or stretched (uniaxially or biaxially), but is preferably a biaxially stretched film from the viewpoint of thermal dimensional stability.

The thickness of the base film is not particularly limited, but is preferably 1 μm to 100 μm, more preferably 5 μm to 50 μm, and more preferably 10 μm to 30 μm.

The surface of the substrate film may optionally be subjected to corona treatment, ozone treatment, plasma treatment, glow discharge treatment, or the like, in order to improve adhesion with the inorganic compound layer.

[Inorganic layer]
The inorganic layer according to the present invention is a single layer, contains a metal at least on the surface in contact with the base film, and further contains a metal oxide on at least the surface in contact with the protective layer. This also means that the inorganic layer is in contact with the substrate film and the protective layer. By including a metal on the surface of the inorganic layer in contact with the base film, it is possible to achieve both high gas barrier properties, bending resistance, and tensile resistance, and the surface of the inorganic layer in contact with the protective layer includes a metal oxide. , the adhesion to the protective layer can be exhibited.

In addition, the fact that the inorganic layer is a single layer means that there is no interface due to the composition in the inorganic layer. That is, the metal oxide present on the surface side in contact with the protective layer in the inorganic layer and the metal present in the surface side in contact with the substrate film in the inorganic layer are one without an interface in the thickness direction of the inorganic layer. It means that it exists in one layer. For example, when observing the cross section of an inorganic layer, when a plurality of layers with different compositions are laminated, an interface is observed in the cross section within the layer. Insufficient flex resistance and tensile resistance due to peeling, and insufficient gas barrier properties. On the other hand, if the same layer has parts with different compositions in the same layer as in the present invention, a laminate having high adhesiveness, high flex resistance, high tensile resistance, and gas permeability can be obtained. The single-layered inorganic layer containing a metal on the surface in contact with the substrate film and containing a metal oxide on the surface in contact with the protective layer can be formed from a metal layer made of a metal in a vacuum chamber or the like, as described later. It is possible to obtain a deposited layer whose composition changes continuously on the metal oxide layer by a method of forming it in one step.

The metal in the inorganic layer is not particularly limited, but includes aluminum, magnesium, titanium, tin, indium, silicon and zinc, and these may be used singly or in combination of two or more. Furthermore, the metal oxide in the inorganic layer is not particularly limited as long as it is a metal oxide, and examples thereof include oxides of aluminum, magnesium, titanium, tin, indium, silicon and zinc. or a mixture of two or more. Furthermore, the inorganic layer may comprise other compounds, for example other metal compounds such as nitrides of aluminum, magnesium, titanium, tin, indium, silicon, zinc. Aluminum is preferable as the metal in the inorganic layer from the viewpoint of processing cost, gas barrier performance, and thermal conductivity when used in the above-described vacuum heat insulating material. Examples of metal oxides in the inorganic layer include aluminum oxide, magnesium oxide, titanium oxide, tin oxide, indium oxide alloy, silicon oxide, and silicon oxynitride, and examples of metal nitrides include aluminum nitride, titanium nitride, and silicon nitride. is mentioned. These inorganic compounds including inorganic oxides may be used alone or as a mixture of two or more. Among these, aluminum oxide is preferable as the metal oxide in the inorganic layer from the viewpoint of processing cost, gas barrier performance, and thermal conductivity when used in the vacuum heat insulating material described above.

The method for forming the inorganic layer is not particularly limited, and can be formed by known methods such as vapor deposition, sputtering, ion plating, and plasma vapor deposition, but vacuum vapor deposition is preferred from the viewpoint of productivity.

The total thickness of the inorganic layers is preferably 5 nm or more and 150 nm or less. If it is less than 5 nm, the barrier properties may be insufficient, while if it is more than 150 nm, the cohesive force may be lowered, causing cohesive failure in the metal layer and cracking or peeling of the inorganic layer.

In the inorganic layer of the present invention, when the element concentration of the metal element in the inorganic layer is M, the element concentration of the oxygen element is O, and the ratio thereof is M / O, at least a part of the region in the thickness direction of the inorganic layer , M/O values preferably have a continuous increase or decrease. By providing a protective layer on the inorganic layer whose composition changes continuously, it not only compensates for the imperfect gas barrier performance of the metal layer, but also exerts the effect of strengthening the adhesion between the metal layer and the gas barrier resin layer, resulting in high gas barrier performance. Both flex resistance and tensile resistance can be achieved.

Further, in the inorganic layer of the present invention, in order to develop high gas barrier properties, it is preferable to have a region in which the length in the thickness direction of the portion where the value of M/O is 20 or more is 10 nm or more, more preferably. It is 20 nm or more, more preferably 40 nm or more. It should be noted that the length in the thickness direction of the portion where the value of M/O is 20 or more is preferable because the closer it is to the total thickness of the inorganic layer, the higher the gas barrier property is expressed, but the portion where the value of M/O is 20 or more If the length in the thickness direction exceeds 150 nm, the cohesive force is reduced as described above, and cohesive failure may occur in the metal layer, causing cracking or peeling of the inorganic layer.

Furthermore, in the inorganic layer of the present invention, it is preferable to have a region in which the length in the thickness direction of the portion where the value of M / O is 1 or less is 5 nm or more, more preferably, in order to express high adhesion. The length in the thickness direction of the portion where the value of M/O is 1 or less is 10 nm or more. If the length in the thickness direction of the portion where the value of M/O is 1 or less exceeds 30 nm, adhesion is likely to occur, but the layer tends to be hard, and flex resistance and tensile resistance may be impaired. Therefore, it is preferably 30 nm or less.

As an example of a method of forming an inorganic layer so that the value of M/O continuously increases or decreases in at least a partial region in the thickness direction of the inorganic layer in the present invention, an aluminum metal layer to an aluminum oxide layer Next, a method for forming a deposited layer whose composition changes continuously will be described. In this case, it is preferable to use a method in which a deposited layer whose composition changes continuously from an aluminum metal layer to an aluminum oxide layer is formed in a vacuum chamber. The vapor deposition may be carried out by known methods such as vapor deposition and sputtering, but the vapor deposition method is preferable from the viewpoint of productivity, and the heating and vaporization of aluminum for that purpose is a method such as resistance heating, high frequency heating, or electron beam heating. is applicable. In these vapor deposition methods, it is preferable to form an inorganic layer whose composition changes continuously from an aluminum metal layer to an aluminum oxide layer by reactive vapor deposition. That is, the base film is generally long and is supplied in a roll, is unwound from the roll in a vacuum chamber, vapor deposition is performed, and is wound again into a roll. An aluminum metal layer is formed, oxygen is introduced in the latter part of the deposition, and aluminum oxide is formed by the reaction of metallic aluminum and oxygen. Oxygen introduced in the second half of vapor deposition diffuses from the winding side of the substrate film toward the unwinding side, so that the metal aluminum layer and the aluminum oxide layer are not strictly separated from each other. Depending on the position of the vapor deposition zone through which the film passes, the reaction of oxygen proceeds continuously from the aluminum metal layer to the aluminum oxide layer, and a gradient structure in which the composition changes continuously in the film thickness direction can be formed. A continuous increase or decrease in the value of M/O may be provided in at least some regions of the direction.

In addition, the value of M / O is adjusted as appropriate, and the length in the thickness direction of the portion where the value of M / O is 20 or more is 10 nm or more. As a method for providing a region in which the length of the portion in the thickness direction of 1 or less is 5 nm or more, the amount of oxygen, the introduction speed, the oxygen nozzle, etc. when introducing oxygen in the latter half of the vapor deposition described above. It can be controlled by adjusting or changing the position, shape, number of inlets, conveying speed of the base film, etc., but not limited to these.

[Protective layer]
The protective layer contains vinyl resin and linear polysiloxane. It contains vinyl resin and linear polysiloxane, and by forming and fixing a network in the protective layer, it suppresses the movement of the molecular chains of the components that make up the protective layer, and prevents oxygen and water vapor from changing due to environmental changes such as temperature. Since it is possible to suppress the expansion of the permeation path, it is considered to be a protective layer with a dense and tough structure.

Examples of vinyl-based resins include polyvinyl alcohol, ethylene-vinyl alcohol copolymer, modified polyvinyl alcohol, etc. These resins may be used alone or in a mixture of two or more, but are preferably It is a vinyl alcohol resin (including modified polyvinyl alcohol). Vinyl alcohol resins (including modified polyvinyl alcohol) are generally obtained by saponifying polyvinyl acetate. However, a higher degree of saponification is preferred. The degree of saponification is preferably 90% or higher, more preferably 95% or higher. If the degree of saponification is low and a large amount of acetic acid groups with large steric hindrance are contained, the free volume of the layer may increase. The degree of polymerization of the vinyl alcohol resin is preferably 1,000 or more and 3,000 or less, more preferably 1,000 or more and 2,000 or less. If the degree of polymerization is low, the polymer may be difficult to fix, resulting in a decrease in flex resistance and tensile resistance.

Furthermore, a particularly preferable vinyl resin is a vinyl resin having a carbonyl group in the cyclic structure. By including a vinyl resin having a carbonyl group in the cyclic structure as the vinyl resin in the protective layer, the cyclic structure makes the resin hydrophobic and the carbonyl group interacts with the surroundings of the resin to form a film with a dense structure and water resistance. It becomes a protective layer with a dense structure that is less hydrophilic, reduces interaction with gas molecules such as oxygen and water vapor, and blocks the permeation path of gas molecules, thereby exhibiting excellent gas barrier properties. Conceivable. The vinyl resin having a carbonyl group in the cyclic structure of the present invention is preferably 20 to 100 wt % with respect to 100 wt % of the total vinyl resin in the protective layer. If it is less than 20 wt%, the effect of improving the gas barrier properties may be poor, and 100 wt% is the most preferable because all the vinyl resins are vinyl resins having a carbonyl group in the cyclic structure.

The cyclic structure is not particularly limited as long as it is a three- or more-membered ring (for example, a three- to six-membered ring). It may be a cyclic structure such as a heterocycle having In addition, the carbonyl group-containing site in this cyclic structure may be present in either the main chain, the side chain, or the crosslinked chain of the vinyl-based resin. Specific examples of the vinyl-based resin having a carbonyl group in the cyclic structure include, for example, a lactone structure that is a cyclic ester and a lactam structure that is a cyclic amide. Although it may be present and is not particularly limited, it is preferably a lactone structure. When a vinyl-based resin having a lactone structure is used as the vinyl-based resin, it is stable against an acid catalyst used for hydrolysis of a metal alkoxide described later, and gas barrier properties can be easily maintained. Examples of vinyl resins having a lactone structure include α-acetolactone, β-propiolactone, γ-butyrolactone, δ-valerolactone and the like.

Linear polysiloxane is represented by the following chemical formula (1), where n in chemical formula (1) is an integer of 2 or more. R in the chemical formula (1) includes lower alkyl groups such as methyl group, ethyl group, n-propyl group and n-butyl group, and branched alkyl groups such as iso-propyl group and t-butyl group. Linear polysiloxane has few pores in its molecular chain, and the molecular chains can exist at high density, so it is thought that the path through which oxygen and water vapor can pass can be blocked, and the barrier properties are enhanced. In the present invention, n is preferably 5 or more, more preferably 10 or more, because if the linear structure of the linear polysiloxane is long, it becomes easier to form a network in the protective layer and fix it.

Linear polysiloxanes can be obtained from metal alkoxides represented by Si(OR) ₄ . R in the metal alkoxide is preferably a lower alkyl group such as methyl group, ethyl group, n-propyl group and n-butyl group. Specific examples of metal alkoxides include tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, and tetrabutoxysilane, which may be used singly or in combination of two or more. Metal alkoxides can be hydrolyzed to give linear polysiloxanes, for example. Metal alkoxides are hydrolyzed in the presence of Si(OR) ₄ , water, catalysts and organic solvents. The amount of water used for hydrolysis is preferably 0.8 equivalents or more and 5 equivalents or less with respect to the alkoxy groups of Si(OR) ₄ . If the amount of water is less than 0.8 equivalents, hydrolysis may not proceed sufficiently, and linear polysiloxane may not be obtained. If the amount of water is more than 5 equivalents, the reaction of the metal alkoxide, which will be described later, proceeds randomly to form a large amount of non-linear polysiloxane, and linear polysiloxane may not be obtained.

The catalyst used for hydrolysis is preferably an acid catalyst. Examples of acid catalysts include hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, acetic acid, tartaric acid, etc., and are not particularly limited. Generally, the hydrolysis and polycondensation reaction of metal alkoxides can proceed with either an acid catalyst or a base catalyst, but when an acid catalyst is used, the monomers in the system tend to be hydrolyzed on average. , which tends to be linear. On the other hand, when a base catalyst is used, hydrolysis and polycondensation reactions of alkoxides bonded to the same molecule tend to proceed easily, so the reaction proceeds randomly and the reaction product tends to have many voids. The amount of the catalyst used is preferably 0.1 mol % or more and 0.05 mol % or less with respect to the total molar amount of metal alkoxide.

As the organic solvent used for hydrolysis, alcohols such as methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol and n-butyl alcohol miscible with water and metal alkoxide can be used.

The hydrolysis temperature is preferably 20°C or higher and 45°C or lower. If the reaction is carried out at less than 20° C., the reactivity may be low and the hydrolysis of Si(OR) ₄ may be difficult to proceed. On the other hand, if the reaction is carried out at a temperature exceeding 45° C., the hydrolysis and polycondensation reactions may proceed rapidly, resulting in gelation or random and sparse polysiloxane that is not linear.

The protective layer of the present invention may separately contain a metal alkoxide (including a hydrolyzate of metal alkoxide) in addition to the vinyl resin and linear polysiloxane.

In the present invention, the total content of all vinyl-based resins in the protective layer is preferably 20-80 wt % in 100 wt % of the protective layer. When the content of the vinyl resin is 20 to 80 wt%, the protective layer tends to have a dense and tough structure and exhibits high flex resistance and tensile resistance. If the vinyl-based resin content is less than 20 wt %, the protective layer tends to be hard, cracks may occur, and gas barrier properties may deteriorate. If the content of the vinyl resin is more than 80 wt %, the vinyl resin cannot be fixed, and the gas barrier properties may deteriorate. The vinyl resin content is more preferably 30 to 60 wt%, more preferably 35 to 50 wt%. The total content of all linear polysiloxanes in the protective layer can be 20 to 80 wt% in 100 wt% of the protective layer. ) may be included separately, the content ratio is calculated by converting the linear polysiloxane and metal alkoxide into _SiO2 , and the inorganic component in the protective layer (hereinafter, the inorganic component in the protective layer is referred to as the protective layer Inorganic components) is preferably 20 to 80 wt % in 100 wt % of the protective layer. The contents of the vinyl-based resin in the protective layer and the inorganic component of the protective layer can be measured by the method described later.

Furthermore, it is also possible to adjust the mixing ratio of the linear polysiloxane and the metal alkoxide in the protective layer inorganic component. The range of polysiloxane/metal alkoxide=15/85 to 90/10 is preferred, the range of 50/50 to 85/15 is more preferred, and the range of 60/40 to 85/15 is even more preferred. If this value exceeds 90/10, the interaction between linear polysiloxanes becomes strong and the organic component cannot be immobilized, resulting in a decrease in gas barrier properties. On the other hand, if it is less than 15/85, the number of Si—OH bonds derived from the metal alkoxide increases, which may increase the hydrophilicity and lower the barrier properties. The mixing ratio of linear polysiloxane and metal alkoxide in the inorganic component can be measured by the method described later.

As the linear polysiloxane, the content ratio of the organic component and the inorganic component and the mixing ratio of the linear polysiloxane and the metal alkoxide can be easily adjusted by using an oligomer raw material in which a plurality of Si(OR) ₄ are bonded in advance. can be adjusted to Examples of oligomer raw materials in which a plurality of Si(OR) ₄ are bonded in advance include alkyl silicates such as methyl silicate in which R in chemical formula (1) is a methyl group, and ethyl silicate in which R is an ethyl group. Linear oligomers are mentioned.

In the present invention, the linear polysiloxane and metal alkoxide contained in the protective layer can be heat-induced to undergo a polycondensation reaction to form the protective layer. When the polycondensation reaction proceeds, the alkoxy groups and/or hydroxyl groups contained in the linear polysiloxane and metal alkoxide are reduced, resulting in a dense and strong protective layer. In addition, the polycondensation reaction increases the molecular weight of the linear polysiloxane and the metal alkoxide, thereby increasing the ability to fix the vinyl resin. Therefore, a higher temperature is preferable because the gas barrier property, flex resistance, and tensile resistance of the protective layer can be improved by advancing the reaction with heat. However, if the temperature exceeds 200° C., the substrate film may shrink due to heat, or the inorganic layer may be distorted or cracked, resulting in a decrease in barrier properties.

The protective layer is formed by applying a coating liquid (hereinafter referred to as protective layer coating liquid) containing vinyl resin and inorganic components such as linear polysiloxane and metal alkoxide (including hydrolyzate of metal alkoxide) to the inorganic layer. It can be obtained by coating and drying. Therefore, the drying temperature of the coating film, which is the temperature for advancing the polycondensation reaction, is preferably 100° C. or higher and 200° C. or lower, more preferably 120° C. or higher and 180° C. or lower, and 150° C. or higher and 180° C. or higher. °C or less is more preferable. If the temperature is less than 100° C., water contained as a solvent, which will be described later, may not sufficiently evaporate, and the layer may not be cured.

The protective layer coating solution can be obtained by mixing a vinyl resin dissolved in water or a water/alcohol mixed solvent with a solution containing linear polysiloxane or metal alkoxide. Examples of alcohols used as solvents include methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol and the like.

The method for applying the protective layer coating liquid onto the inorganic layer is known without particular limitation, such as direct gravure, reverse gravure, micro gravure, rod coating, bar coating, die coating, and spray coating. method can be used.

The protective layer according to the present invention may contain a leveling agent, a cross-linking agent, a curing agent, an adhesion agent, a stabilizer, an ultraviolet absorber, an antistatic agent, etc., as long as the barrier properties are not impaired. Examples of cross-linking agents include metal alkoxides such as aluminum, titanium, and zirconium, and complexes thereof.

The average thickness of the protective layer is preferably 10 nm or more and 1,000 nm or less, more preferably 100 nm or more and 600 nm or less, and still more preferably 350 nm or more and 500 nm or less. If the average thickness is less than 10 nm, pinholes and cracks in the inorganic layer cannot be sufficiently filled, and a sufficient gas barrier function may not be exhibited. On the other hand, if the thickness exceeds 1,000 nm, cracks may occur due to the thickness.

As described above, the protective layer undergoes a condensation reaction due to heat, and has a high barrier property. Therefore, it is also preferable to further heat-treat the laminate after forming the protective layer in order to improve the barrier properties. The heat treatment temperature is preferably 30° C. or higher and 100° C. or lower, more preferably 40° C. or higher and 80° C. or lower. The heat treatment time is preferably 1 to 14 days, more preferably 3 to 7 days. If the heat treatment temperature is less than 30°C, the heat energy required to promote the reaction may be insufficient and the effect may be small. cost may be high.

[Analysis of laminate]
The presence of linear polysiloxane in the protective layer according to the present invention can be confirmed by laser Raman spectroscopy. In laser Raman spectroscopy, the bonding state of linear polysiloxane and metal alkoxide (including hydrolyzate of metal alkoxide) is linear polysiloxane and a structure that includes a ring structure of five or more members and branches. A random network structure and a Raman band of a four-membered ring structure are observed at 400-500 cm ⁻¹ . Since these Raman bands are superimposed, the four-membered ring structure is 495 cm ^-1 , the linear polysiloxane is 488 cm ^-1 , and the random network structure is not a single regular structure, so a band with a spread of 450 cm ^-1 or less are observed, and these can be fitted with a Gaussian function approximation to separate the peaks.

A method for determining the content of the vinyl resin in the protective layer and the inorganic component of the protective layer will be described. The amount of linear polysiloxane and metal alkoxide (including hydrolysates of metal alkoxide), which are inorganic components, can be replaced with the amount of silicon as described above, and the amount of silicon can be obtained by fluorescent X-ray analysis. can. First, five types of standard samples with known and different amounts of silicon are prepared, and fluorescent X-ray analysis is performed on each sample. Fluorescent X-ray analysis generates and detects fluorescent X-rays peculiar to elements by X-ray irradiation. Since the amount of X-rays generated is proportional to the amount of elements contained in the object to be measured, the X-ray intensity S (unit: cps/μA) of silicon obtained by measurement and the amount of silicon are in a proportional relationship. Here, the thickness of the standard sample is calculated in the same manner as the average thickness T described later, and the X-ray intensity S obtained by fluorescent X-ray analysis is divided by the thickness of the standard sample to obtain the X-ray intensity S per unit thickness. Then, the known amount of silicon and the X-ray intensity S per unit thickness are plotted to prepare a calibration curve. After that, in the laminate of the present invention, the X-ray intensity S per unit thickness is similarly obtained from the fluorescent X-ray analysis and the average thickness T, and the amount of silicon is calculated from the calibration curve and its value. From this amount of silicon, the total number of moles of silicon atoms contained in the linear polysiloxane and the metal alkoxide is obtained and converted to the mass of SiO ₂ to obtain the total mass ratio S of the protective layer inorganic components, and the vinyl resin and the protective The content of layer inorganic components can be determined.

The mixing ratio of the linear polysiloxane and the metal alkoxide in the protective layer inorganic component in the protective layer is the area A1 of the Raman band showing a random network structure, obtained by measurement by the laser Raman spectroscopy, and the linear poly A2/A1, which is the ratio of the area A2 of the Raman band representing siloxane, is the mixing ratio of linear polysiloxane/metal alkoxide (mass ratio in terms of SiO ₂ ).

[Use]
INDUSTRIAL APPLICABILITY The laminate of the present invention has excellent oxygen and water vapor barrier performance, and can be suitably used as a laminate having lamination strength, bending resistance, and tensile resistance, as well as a sealing member for vacuum heat insulation containing the same. can be done.

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

(1) Analysis of inorganic layer, M/O value (ratio of metal element concentration M and oxygen concentration O)
Using X-ray photoelectron spectroscopy (XPS), composition analysis evaluation was performed in the depth direction, and the inorganic film structure was confirmed by the depth profile. As for the metal elements, the oxide component and the metal component were separated and profiled. While performing ion etching from the surface layer on the protective layer side, data was collected until reaching the substrate film, and the presence or absence of continuous increase or decrease in the M/O value was confirmed from the obtained depth profile of each element. Regarding the presence or absence of continuous increase or decrease, it was judged that there was continuous increase or decrease when the length of the increase or decrease was 2 nm or more.
The measurement conditions were as follows.
・ Apparatus: X-ray photoelectron spectrometer (Quantera SXM manufactured by PHI)
・Excitation X-ray: monochromatic AlKα _1,2 rays (1486.6 eV)
・X-ray diameter: 100 μm
Photoelectron escape angle: 45° (detector tilt with respect to sample surface)
・Ion etching conditions: Ar ⁺ ion 3 kV
Raster size 2 x 2 mm (etching area)
Etching rate: 12.0 nm/min Subsequently, the total thickness of the inorganic layer was obtained by the method described later. From the total thickness of the inorganic layer and the region corresponding to the inorganic layer in the depth profile, the length in the thickness direction of the portion where the M/O value is 20 or more and the length in the thickness direction of the portion where the M/O value is 1 or less were calculated.

(2) Component Analysis and Structure Identification of Protective Layer The protective layer was peeled off from the sample and dissolved in a soluble solvent. If necessary, general chromatography such as silica gel column chromatography, gel permeation chromatography, liquid high performance chromatography, etc. was applied to separate and purify the components contained in the protective layer into individual substances. Thereafter, DMSO-d ₆ was added to each single substance, heated to 60° C. to dissolve, and this solution was subjected to ¹ H-NMR and ¹³ C-NMR measurements using nuclear magnetic resonance spectroscopy. Then, for each single substance, IR method (infrared spectroscopy), various mass spectrometry methods (gas chromatography-mass spectrometry (GC-MS), pyrolysis gas chromatography-mass spectrometry (pyrolysis GC-MS) , matrix-assisted laser desorption ionization mass spectrometry (MALDI-MS), time-of-flight mass spectrometry (TOF-MS), time-of-flight matrix-assisted laser desorption ionization mass spectrometry (MALDI-TOF-MS), dynamic secondary ion Qualitative analysis was performed by appropriately combining mass spectrometry (Dynamic-SIMS) and time-of-flight secondary ion mass spectrometry (TOF-SIMS), and the components contained in the sample were specified and their structures were identified. When these qualitative analyzes were combined, those that could be measured with fewer combinations were given priority.

(3) Average Thickness of Protective Layer and Total Thickness of Inorganic Layer The average thickness of the protective layer and the total thickness of the inorganic layer were obtained by observing the cross section with a TEM. First, a sample for cross-sectional observation is subjected to the FIB method using a microsampling system (FB-2000A manufactured by Hitachi, Ltd.) (specifically, "Polymer Surface Processing" (by Akira Iwamori) pp. 118-119 (based on the method described in ). Then, using a transmission electron microscope (H-9000UHRII manufactured by Hitachi, Ltd.), observation is performed at an acceleration voltage of 300 kV, and the ratio of the layer thickness in the observed image of the obtained cross section is 30 to 70%. The observation magnification was adjusted as follows. A total of 5 samples were measured in the same manner, and an average value of 5 points was calculated.

(4) Measurement of content ratio of vinyl resin in protective layer and protective layer inorganic component (linear polysiloxane, metal alkoxide) 700, saponification degree 98.5%) and a hydrolyzate of tetraalkoxysilane (hereinafter sometimes abbreviated as TEOS) as an inorganic component, and the content ratio of vinyl resin / inorganic component (inorganic component is SiO ₂ mass Films obtained by mixing so that the conversion) were 80/20, 65/35, 50/50, 35/65, and 20/80 were prepared as standard samples with different contents.

Next, for each standard sample, the intensity of the specific X-ray Kα of silicon was measured using a fluorescent X-ray analyzer EDX-700 manufactured by Shimadzu Corporation, and the obtained X-ray intensity S (unit: cps/μA) was measured. asked. By the method described in (3) above, the thickness of each standard sample is measured, the X-ray intensity S per unit thickness is calculated, and the content of the vinyl resin and the inorganic component of the protective layer (inorganic component is converted to SiO ₂ mass ) to create a calibration curve.

Next, for the laminate of the present invention, the X-ray intensity S per unit thickness was determined from the fluorescent X-ray analysis and the average thickness T in the same manner, and the contents of the vinyl resin and the inorganic component of the protective layer were determined from the calibration curve.

(5) Analysis of bonding state of silicon (presence or absence of linear polysiloxane), (mixing ratio of linear polysiloxane/metal alkoxide (mass ratio in terms of _SiO2 ))
The protective layer of the laminate was separated by cutting and analyzed by Raman spectroscopy using the following conditions.
Measuring device: Jobin Yvon/Atago Bussan T-6400
Measurement mode: Microscopic Raman objective lens: 100 times Beam diameter: 1 μm
Light source: Ar ⁺ laser/514.5 nm
Laser power: 200mW
Diffraction grating: Single 600gr/mm
Slit: 100 μm
Detector: CCD/Jobin Yvon 1,024×256
The Raman spectrum analysis conditions for calculating the area A1 representing the random network structure composed of the metal alkoxide and the area A2 representing the linear polysiloxane are as follows. The obtained Raman spectrum was analyzed using spectrum analysis software GRAMS/Thermo Scientific. After baseline correction of the Raman spectrum by linear approximation, fitting was performed in the range of 600 to 250 cm ⁻¹ . The fitting consists of three components: a four-membered ring structure (peak wavenumber 495 cm ⁻¹ , half width 35 cm ⁻¹ ), linear polysiloxane (peak wavenumber 488 cm ⁻¹ , half width 35 cm ⁻¹ ), and a random network structure composed of metal alkoxide. separated into Since the random network structure composed of metal alkoxide has a broad peak reflecting the continuous structure, automatic fitting was performed assuming that the 3 components combined with the 4-membered ring structure and linear polysiloxane were separated by Gaussian function approximation.

By calculating the area of the region surrounded by the obtained band and the baseline, the presence or absence of linear polysiloxane is determined, and the area representing the random network structure composed of metal alkoxide is A1, the linear A2/A1 (mixing ratio of linear polysiloxane/metal alkoxide (mass ratio in terms of SiO ₂ )) was calculated, where A2 represents the area representing polysiloxane.

(6) Oxygen transmission rate Oxygen transmission rate (hereinafter sometimes abbreviated as OTR) was measured using an oxygen transmission rate measuring device (OX-TRAN (OX-TRAN (registered trademark) 2/21) and measured based on B method described in JIS K7126 (2006). The measurement was performed twice for each of the two test pieces, and the average value of the four measurements was taken as the value of the oxygen transmission rate.

(7) Water vapor transmission rate Water vapor transmission rate (hereinafter sometimes abbreviated as WVTR) is measured by a water vapor transmission rate measuring device (PERMATRAN ( (registered trademark)-W 3/31) was measured based on the B method described in JIS K7126 (2006). The measurement was performed twice for each of the two test pieces, and the average value of the four measurements was taken as the value of the water vapor transmission rate.

(8) Laminate strength (adhesion)
A straight-chain sealant film having a thickness of 40 μm is applied to the laminate via an adhesive consisting of a polyester urethane-based main agent (LX500, manufactured by DIC Corporation) and an aromatic isocyanate curing agent (KW75, manufactured by DIC Corporation). A laminated film was prepared by laminating low-density polyethylene films by a dry lamination method. Next, the laminated film is cut to a width of 15 mm and a length of 150 mm to create a cut sample, and a tensile tester (Tensilon) is used to make the interface between the laminate and the linear low-density polyethylene film by the T peel method. Peel strength (laminate strength) was measured at a pulling speed of 50 mm/min. Adhesion was judged to be good when the peel strength value was 3.0 N/15 mm or more.

The same measurement was performed for a total of 5 samples, and if there was adhesion in all 5 samples, it was passed 1, and if there was adhesion in 3 samples or more and 4 samples or less, it was passed 2. Pass 1 has the best adhesion. indicate that In addition, when the value of the peel strength was larger than 3.0 N/15 mm, it was regarded as unsuccessful, and when it did not fall under any of the criteria of Pass 1 and Pass 2, it was regarded as Pass 3.

(9) Oxygen Permeability and Water Vapor Permeability after Tensile Elongation Test A sample of the laminate was cut into a 140 mm × 90 mm test piece, and 5% (7 mm) was pulled from both ends of the 90 mm side of the test piece at a speed of 5 mm / min. Oxygen transmission rate and water vapor transmission rate were measured using the test piece.

Tensile resistance is judged by the following criteria for the amount of change in oxygen permeability value and water vapor permeability value before and after the tensile elongation test. Pass 1 has the highest tensile resistance, followed by Pass 2 and Pass. It shows that it has tensile resistance in order of 3.
(Passed 1)
・The amount of change in oxygen permeability value is 0.1 cc/m ² ·24 hr·atm or less, and the amount of change in water vapor permeability value is 0.1 g/m ² ·24 hr·atm or less.
(Passed 2)
・The amount of change in oxygen permeability value is greater than 0.1 cc/ ^m2 ·24 hr·atm and not more than 0.3 cc/ ^m2 ·24 hr·atm, and the amount of change in water vapor permeability value is 0.1 g/ ^m2 ·24 hr.・Satisfies any one of 0.3 g/m ² ·24 hr · atm or less greater than atm.
(Passed 3)
・The amount of change in oxygen permeability value is greater than 0.3 cc/ ^m2 ·24 hr·atm and not more than 0.5 cc/ ^m2 ·24 hr·atm, and the amount of change in water vapor permeability value is 0.3 g/ ^m2 ·24 hr.・Satisfies any one of 0.5 g/m ² ·24 hr · atm or less greater than atm.
(failure)
・If none of the conditions for passing 1 to 3 are met.

(10) Oxygen permeability and water vapor permeability after bending fatigue test A sample cut of the laminate into a 200 mm × 300 mm test piece was performed, and both ends of the 300 mm side of the test piece were bonded together and rolled into a cylindrical shape. Both ends of the strip were held by a fixed head and a driving head, and while a 440 degree twist was applied, the distance between the fixed head and the driving head was reduced from 7 inches to 3.5 inches. inch, then widen the distance between the heads to 3.5 inches, and then widen the distance between the heads to 7 inches while untwisting at a speed of 40 times/min three times in a bending fatigue test. Oxygen transmission rate and water vapor transmission rate were measured using the test pieces before and after.

Regarding the pass/fail judgment of bending resistance, the amount of change in the oxygen permeability value and the water vapor permeability value before and after the bending fatigue test is the same as described in the above "(9) Oxygen permeability and water vapor permeability after tensile elongation test". Pass 1 has the highest flex resistance, followed by Pass 2 and Pass 3 in order of tensile resistance. In this evaluation, a failure was defined as a case where none of the conditions of Passes 1 to 3 were satisfied.

[Example 1]
<Inorganic layer>
A 12 μm-thick biaxially oriented polyethylene terephthalate film (“Lumirror” (registered trademark) P60 manufactured by Toray Industries, Inc.) was used as the base film, and aluminum was evaporated using a high-frequency induction heating crucible method using a roll-to-roll vacuum deposition machine. Using a source, the inorganic layers were continuously formed such that the aluminum metal layer had a thickness of 40 nm and the aluminum oxide layer had a thickness of 4 nm. On the base film, films having a composition corresponding to the position are sequentially formed in the thickness direction within a zone having a constant width in the traveling direction of the base film on a cooled rotating drum. Oxygen was supplied from the last position to be vapor-deposited to form a vapor-deposited layer (inorganic layer) that continuously changed from an aluminum metal layer to an aluminum oxide layer.
<Protective layer>
As a vinyl resin, polyvinyl alcohol (hereinafter sometimes abbreviated as PVA; degree of polymerization: 1,700; degree of saponification: 98.5%) was added to a solvent with a mass ratio of water/isopropyl alcohol = 97/3. C. to obtain a PVA solution with a solid content of 10% by mass.

Next, 7.0 g of a 0.06N hydrochloric acid aqueous solution was added to a solution obtained by mixing 11.2 g of Ethyl Silicate 40 (average pentamer linear oligomer) manufactured by Colcoat Co., Ltd. as a linear polysiloxane and 16.9 g of methanol. to obtain a pentamer silicate hydrolyzate.

Next, the PVA solution and the pentamer silicate hydrolyzate were mixed and stirred so that the PVA solid content was 19 wt%, and diluted with water to obtain a protective layer coating solution with a solid content of 12 wt%. rice field. This coating solution was applied onto the inorganic layer by gravure coating and then dried at 180° C. to form a protective layer having an average thickness of 550 nm after drying to form a laminate.

[Example 2]
<Inorganic layer>
An inorganic layer was formed in the same manner as in Example 1, except that the inorganic layer was formed so that the aluminum metal layer had a thickness of 9 nm and the aluminum oxide layer had a thickness of 7 nm.
<Protective layer>
A protective layer coating solution was obtained in the same manner as in Example 1, except that the solid content of PVA was adjusted to 22 wt %. A laminate was obtained in the same manner as in Example 1, except that the protective layer was formed so as to have an average thickness of 350 nm after the coating liquid was dried.

[Example 3]
<Inorganic layer>
An inorganic layer was formed in the same manner as in Example 1, except that the inorganic layer was formed so that the aluminum metal layer had a thickness of 15 nm and the aluminum oxide layer had a thickness of 7 nm.
<Protective layer>
A protective layer coating solution was obtained in the same manner as in Example 1, except that the solid content of PVA was adjusted to 83 wt%. A laminate was obtained in the same manner as in Example 1, except that the protective layer was formed so as to have an average thickness of 350 nm after the coating liquid was dried.

[Example 4]
<Inorganic layer>
An inorganic layer was formed in the same manner as in Example 1, except that the inorganic layer was formed so that the aluminum metal layer had a thickness of 25 nm and the aluminum oxide layer had a thickness of 7 nm.
<Protective layer>
A protective layer coating solution was obtained in the same manner as in Example 1, except that the PVA solid content was adjusted to 77 wt %. A laminate was obtained in the same manner as in Example 1, except that the protective layer was formed so as to have an average thickness of 350 nm after the coating liquid was dried.

[Example 5]
<Inorganic layer>
An inorganic layer was formed in the same manner as in Example 1, except that the inorganic layer was formed so that the aluminum metal layer had a thickness of 40 nm and the aluminum oxide layer had a thickness of 13 nm.
<Protective layer>
A protective layer coating solution was obtained in the same manner as in Example 1, except that the solid content of PVA was adjusted to 35 wt %. A laminate was obtained in the same manner as in Example 1, except that the protective layer was formed so as to have an average thickness of 350 nm after the coating liquid was dried.

[Example 6]
<Inorganic layer>
An inorganic layer was formed in the same manner as in Example 1, except that the inorganic layer was formed so that the aluminum metal layer had a thickness of 80 nm and the aluminum oxide layer had a thickness of 13 nm.
<Protective layer>
A protective layer coating solution was obtained in the same manner as in Example 1, except that the solid content of PVA was adjusted to 61 wt %. A laminate was obtained in the same manner as in Example 1, except that the protective layer was formed so as to have an average thickness of 350 nm after the coating liquid was dried.

[Example 7]
<Inorganic layer>
An inorganic layer was formed in the same manner as in Example 5.
<Protective layer>
A protective layer was formed in the same manner as in Example 5 so that the average thickness after drying was 350 nm, except that Ethyl Silicate 48 (linear oligomer of average decamer) was used as the linear polysiloxane. A laminate was obtained.

[Example 8 (reference example) ]
<Inorganic layer>
An inorganic layer was formed in the same manner as in Example 5.
<Protective layer>
A PVA solution having a solid content of 10% by mass was obtained in the same manner as in Example 1.

Next, 18.6 g of a 0.02N hydrochloric acid aqueous solution was added dropwise to a mixed solution of 11.7 g of TEOS and 4.7 g of methanol while stirring to obtain a TEOS hydrolyzate. On the other hand, a tetramer silicate hydrolyzate was obtained in the same manner as in Example 1 except that Methyl Silicate 51 (average tetramer linear oligomer) manufactured by Colcoat Co., Ltd. was used as the linear polysiloxane. The tetramer silicate hydrolyzate and the TEOS hydrolyzate were mixed so that the mass ratio of solid content in terms of SiO ₂ was 60/40 to obtain a tetramer silicate/TEOS hydrolyzate mixture.

Next, the PVA solution and the tetramer silicate/TEOS hydrolysis mixed solution were mixed and stirred so that the solid content of PVA was 58 wt%, diluted with water, and coated with a protective layer having a solid content of 12 wt%. I got the liquid. In the same manner as in Example 5, this coating solution was applied onto the inorganic layer by gravure coating and dried at 180° C. to form a protective layer having an average thickness of 350 nm after drying to form a laminate.

[Example 9]
<Inorganic layer>
An inorganic layer was formed in the same manner as in Example 5.
<Protective layer>
Examples except that Methyl Silicate 53A (linear oligomer of average heptamer) manufactured by Colcoat Co., Ltd. was used as the linear polysiloxane, and the solid content of PVA was adjusted to 46 wt%. A protective layer coating liquid was obtained in the same manner as in No. 8. In the same manner as in Example 5, this coating solution was applied onto the inorganic layer by gravure coating and dried at 180° C. to form a protective layer having an average thickness of 350 nm after drying to form a laminate.

[Example 10]
<Inorganic layer>
An inorganic layer was formed in the same manner as in Example 5.
<Protective layer>
Ethyl Silicate 48 manufactured by Colcoat Co., Ltd. (linear oligomer of average decamer) was used as the linear polysiloxane, and the solid content of PVA was adjusted to 35 wt%. A protective layer coating liquid was obtained in the same manner as in No. 8. In the same manner as in Example 5, this coating solution was applied onto the inorganic layer by gravure coating and dried at 180° C. to form a protective layer having an average thickness of 350 nm after drying to form a laminate.

[Example 11]
<Inorganic layer>
An inorganic layer was formed in the same manner as in Example 5.
<Protective layer>
As the vinyl-based resin, modified polyvinyl alcohol having 1,3,5-triazine-2,4,6-trione, which is an isocyanuric acid structure having a carbonyl group in the cyclic structure (hereinafter sometimes abbreviated as modified PVA). A laminate was obtained by forming a protective layer so as to have an average thickness of 550 nm after drying in the same manner as in Example 1, except that the degree of polymerization was 1,700 and the degree of saponification was 93.0%.

[Example 12]
<Inorganic layer>
An inorganic layer was formed in the same manner as in Example 5.
<Protective layer>
Modified polyvinyl alcohol (hereinafter sometimes abbreviated as modified PVA, degree of polymerization 1,700, degree of saponification 93.0%) having γ-lactam, which is a lactam structure having a carbonyl group in the cyclic structure, as the vinyl-based resin A laminate was obtained by forming a protective layer so as to have an average thickness of 550 nm after drying in the same manner as in Example 1, except that the thickness was changed to .

[Example 13]
<Inorganic layer>
An inorganic layer was formed in the same manner as in Example 5.
<Protective layer>
Modified polyvinyl alcohol having γ-butyrolactone, which is a lactone structure having a carbonyl group in the cyclic structure, as the vinyl resin (hereinafter sometimes abbreviated as modified PVA. Degree of polymerization: 1,700; degree of saponification: 93.0%) A laminate was obtained by forming a protective layer so as to have an average thickness of 550 nm after drying in the same manner as in Example 1, except that the thickness was changed to .

[Example 14]
<Inorganic layer>
An inorganic layer was formed in the same manner as in Example 5.
<Protective layer>
Except for using PVA with a low degree of saponification (hereinafter sometimes abbreviated as low saponification PVA, degree of polymerization: 1,700, degree of saponification: 88%) having a carbonyl group but not a cyclic structure and an acetic acid group as the vinyl resin. A laminate was obtained by forming a protective layer in the same manner as in Example 1 so that the average thickness after drying was 550 nm.

[Example 15]
<Inorganic layer>
An inorganic layer was formed in the same manner as in Example 5.
<Protective layer>
Except that modified polyvinyl alcohol (hereinafter sometimes abbreviated as modified PVA, degree of polymerization: 1,700, degree of saponification: 93.0%) having tetrahydrofurfuryl, which has a cyclic structure but no carbonyl group, is used as the vinyl-based resin. A laminate was obtained by forming a protective layer in the same manner as in Example 1 so that the average thickness after drying was 550 nm.

[Example 16]
<Inorganic layer>
An inorganic layer was formed in the same manner as in Example 5.
<Protective layer>
Modified polyvinyl alcohol having γ-butyrolactone, which is a lactone structure having a carbonyl group in the cyclic structure, as the vinyl resin (hereinafter sometimes abbreviated as modified PVA. Degree of polymerization: 1,700; degree of saponification: 93.0%) A laminate was obtained by forming a protective layer so as to have an average thickness of 350 nm after drying in the same manner as in Example 10, except that the protective layer was dried.

[Comparative Example 1]
When evaluation was performed using only the substrate film provided with the same inorganic layer as in Example 1 without providing a protective layer, the gas barrier property of the laminate was inferior. As for tensile resistance and flex resistance, cracks occurred, and breakage and peeling occurred, and both were disqualified.

[Comparative Example 2]
A laminate was obtained by providing a protective layer in the same manner as in Example 1, except that the thickness of the aluminum metal layer alone was adjusted to 50 nm without supplying oxygen to the deposition layer. Although a protective layer was formed, since the surface in contact with the protective layer did not contain a metal oxide, peeling occurred, and the adhesion, tensile resistance, and flex resistance all failed.

[Comparative Example 3]
A laminate was obtained by providing a protective layer in the same manner as in Example 1, except that metal aluminum was evaporated while supplying oxygen gas to the entire surface of the vapor deposition layer, and the thickness of the aluminum oxide layer alone was adjusted to 15 nm. . Since the surface in contact with the protective layer contained a metal oxide, the adhesion with the protective layer was rated as pass 3. However, since it did not have a metal layer, the gas barrier property was inferior to that of Example 1, and cracks occurred. Both tensile resistance and flex resistance were disqualified due to the occurrence of breakage and breakage.

[Comparative Example 4]
On the inorganic layer formed in the same manner as in Example 1, acrylic resin (PMMA resin) instead of vinyl resin was used to form a protective layer having an average thickness of 550 nm as in Example 1 to obtain a laminate. Since the vinyl resin and linear polysiloxane were not included, the gas barrier property was poor, and all of the adhesion, tensile resistance, and flex resistance were unsatisfactory.

[Comparative Example 5]
On the inorganic layer formed in the same manner as in Example 1, a protective layer was formed using only the same PVA solution with a solid content of 10% by mass as in Example 1, but containing only a vinyl resin and linear polysiloxane. Therefore, the gas barrier property was poor, and all of the adhesion, tensile resistance, and flex resistance were unsatisfactory.

[Comparative Example 6]
A laminate was obtained by forming an inorganic layer and a protective layer as follows. The inorganic layer of this comparative example has a metal oxide layer made of silicon oxide on a metal layer made of aluminum. Peeling occurred at the interface between the layer and the metal oxide layer, and all of adhesion, tensile resistance, and flex resistance failed.
<Inorganic layer>
Only an aluminum metal layer was formed to a thickness of 40 nm in the same manner as in Example 1, except that the deposition layer was formed without supplying oxygen.

Next, a sputtering target, which is a sintered material made of silicon dioxide, was prepared. A sputtering/CVD apparatus is used using the sputtering target, argon gas is introduced so that the degree of vacuum is 2×10 ⁻¹ Pa, and an input power of 500 W is applied from a high-frequency power source to generate argon gas plasma. Then, an inorganic layer was formed on the aluminum metal layer having a thickness of 40 nm by sputtering so as to have a thickness of 4 nm.
<Protective layer>
A laminate was obtained by forming a protective layer in the same manner as in Example 1 so as to have an average thickness of 550 nm after drying.

As is clear from the results of each of the above Examples, the laminate of the present invention is excellent in oxygen barrier performance and water vapor barrier performance, and can maintain gas barrier performance in terms of adhesion, tensile resistance, and flex resistance. It was something.

Comparing Example 1 and Example 2, the adhesiveness is improved in Example 2 in which the length in the thickness direction of the portion where the value of M / O is 1 or less is long, while on the other hand, M / O Example 1, in which the length in the thickness direction of the portion where the value of is 20 or more was longer, exhibited higher gas barrier properties. In Examples 3 to 6, gas barrier properties, adhesion, tensile resistance, It was possible to adjust the bending resistance. It was also possible to adjust the gas barrier property, adhesion, tensile resistance, and flex resistance by adjusting the length of the linear polysiloxane contained in the protective layer (Examples 7 to 10).

Furthermore, by including a vinyl resin having a carbonyl group in the cyclic structure in the protective layer, not only gas barrier properties but also tensile resistance and flex resistance are improved (Examples 11 to 13). The resin had good gas barrier properties, tensile resistance, and bending resistance (Example 13). On the other hand, in the case of a vinyl resin having a cyclic structure or a structure without a carbonyl group, improvements in various performances were very slight compared with ordinary vinyl resins (Examples 14 and 15). Example 16, which is the most preferred embodiment, exhibited high performance in all of gas barrier properties, adhesion, tensile resistance, and flex resistance.

On the other hand, when no protective layer is provided (Comparative Example 1), when no metal oxide layer is provided (Comparative Example 2), when the protective layer does not contain a vinyl resin or linear polysiloxane (Comparative Example 4 , 5) were inferior in all of gas barrier property, adhesion, tensile resistance and flex resistance. When the inorganic layer was formed only with the metal oxide layer (Comparative Example 3), adhesion to the protective layer was obtained, but tensile resistance and flex resistance were unsatisfactory. When the inorganic layer is not a single layer, and an oxide layer made of a different metal is laminated on the surface of the metal layer of the inorganic layer (Comparative Example 6), peeling occurs at the interface between the metal layer and the metal oxide layer, resulting in adhesion and tensile resistance. It was unsuccessful in both resistance and flex resistance.

Claims (6)

A laminate having an inorganic layer and a protective layer in this order from the base film side on at least one side of the base film,
The inorganic layer is a single layer (a layer in which an interface due to composition does not exist in the inorganic layer),
The inorganic layer contains a metal at least on the surface in contact with the base film, and contains a metal oxide on at least the surface in contact with the protective layer,
and the protective layer contains a vinyl-based resin and a linear polysiloxane having a linear structure of pentamer or higher,
The metal is aluminum, the metal oxide is aluminum oxide, and the vinyl resin is vinyl alcohol resin (including modified polyvinyl alcohol),
Let M be the element concentration of the metal element in the inorganic layer, O be the element concentration of the oxygen element, and M/O be the ratio thereof. having a region of 10 nm or more,
A laminate , wherein the average thickness of the protective layer is 10 nm or more and 1000 nm or less . 2. The layered product according to claim 1, wherein said portion having a value of M/O of 1 or less has a region having a length of 5 nm or more in the thickness direction. 3. The laminate according to claim 1 , wherein the vinyl resin contains a vinyl resin having a carbonyl group in the cyclic structure. The laminate according to any one of claims 1 to 3 , wherein the vinyl resin contains a vinyl resin having a lactone structure. 5. The laminate according to any one of claims 1 to 4 , wherein the total content of all vinyl resins in said protective layer is 20 to 80 wt%. A sealing member for vacuum heat insulation, comprising the laminate according to any one of claims 1 to 5 .