JP2008230106A - Gas barrier laminate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a transparent gas barrier laminate that causes no deterioration of performance due to a compression/expansion stress coming from an environmental change by relaxing the propagation of an external stress to the barrier layer. <P>SOLUTION: The gas barrier laminate has a transparent primer layer 2, a 5 to 300 nm thick inorganic-vapor deposition layer 3, a composite coat layer 4, and a stress relaxation layer 5 containing 5 to 60 wt.% of an inorganic filler, these layers orderly overlying at least one surface of a plastic base material 1 containing 5 to 60 wt.% of an inorganic filler. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a gas barrier laminate having transparency used in the industrial material field.

  In recent years, packaging materials used for packaging foods, non-foods, pharmaceuticals, etc. have altered oxygen, water vapor, and other contents that permeate the packaging material in order to suppress the alteration of the contents and retain their functions and properties. It is necessary to prevent the influence of the gas to be generated, and it is required to have a gas barrier property for blocking these. Therefore, conventionally, a packaging material using a metal foil such as aluminum, which is less affected by temperature and humidity, as a gas barrier layer has been generally used.

  However, packaging materials using metal foils such as aluminum are not affected by temperature and humidity and have high gas barrier properties, but the contents cannot be confirmed through the packaging materials. Had to be treated as non-combustible material, and metal detectors could not be used for inspection.

  Therefore, as a packaging material that overcomes these disadvantages, for example, on a polymer film as described in Patent Document 1, Patent Document 2, etc., silicon oxide, aluminum oxide is formed by means of forming such as vacuum deposition or sputtering. A film in which a deposited film of an inorganic oxide such as is formed has been developed. These vapor-deposited films are known to have transparency and gas barrier properties such as oxygen and water vapor, and are suitable as packaging materials having transparency and gas barrier properties that cannot be obtained with metal foil or the like. .

Although it is the transparent vapor deposition film which the use range has expanded from said viewpoint, the example used in a severer environment is increasing. For example, in applications such as solar cell backsheets that are exposed to high temperatures and humidity for long periods of time, compression / expansion stress acts on the entire backsheet due to changes in the surrounding environment, and the stress propagates to the barrier layer, which causes the barrier layer itself to be removed. The desired barrier property cannot be maintained because of destruction.
U.S. Pat. No. 3,442,686 Japanese Patent Publication No.63-28017

  The present invention has been made to solve the above problems, and provides a transparent gas barrier laminate in which propagation of external stress to the barrier layer is mitigated and performance is not deteriorated even by compression / expansion stress due to environmental changes. It is in.

The invention according to claim 1 is provided on at least one surface of a plastic substrate containing 5 to 60% by weight of an inorganic filler,
An inorganic vapor deposition layer having a thickness of 5 to 300 nm;
A gas barrier laminate comprising a stress relaxation layer containing 5 to 60% by weight of an inorganic filler.

  Invention of Claim 2 has a transparent primer layer which consists of a composite of a silane wrapping agent or its hydrolyzate, a polyol, and an isocyanate compound between the said plastic base material and the said inorganic vapor deposition layer. The gas barrier laminate according to claim 1, wherein the gas barrier laminate is characterized in that:

  The invention according to claim 3 contains a water-soluble polymer compound and at least one selected from a metal alkoxide, a hydrolyzate thereof, and a polymer thereof between the inorganic vapor deposition layer and the stress relaxation layer. The gas barrier laminate according to claim 1, further comprising a composite coating layer.

  The invention according to claim 4 is characterized in that the silane coupling agent or a hydrolyzate thereof contains a functional group that reacts with at least one of a hydroxyl group of a polyol and an isocyanate group of an isocyanate compound. It is a gas barrier laminated body as described in above.

The invention described in claim 5 includes tetraethoxysilane (Si (OC ₂ H ₅ ) ₄ ), tripropoxyaluminum (Al (OC ₃ H ₇ ) ₃ ), a hydrolyzate thereof and a polymerization thereof in the composite. The gas barrier laminate according to any one of claims 2 to 4, wherein at least one selected from materials is added.

  The invention according to claim 6 is the gas barrier laminate according to any one of claims 2 to 5, wherein the thickness of the transparent primer layer is in the range of 0.001 to 2 μm.

  The invention according to claim 7 is the gas barrier laminate according to any one of claims 3 to 6, wherein the water-soluble polymer compound contains at least polyvinyl alcohol.

  The invention according to claim 8 is characterized in that the metal in the metal alkoxide or the hydrolyzate of the metal alkoxide is Si, Al or a mixture thereof. It is a gas barrier laminate.

  According to the present invention, the plastic substrate itself has a stress relaxation function, and further, a stress relaxation layer containing an inorganic filler forms a sandwich structure that protects the deposited film from external stress, thereby compressing due to environmental changes. / A transparent gas barrier laminate that does not deteriorate in performance even by expansion stress can be provided.

  Further, according to a preferred embodiment of the present invention, after laminating a transparent primer layer on a plastic substrate into which an inorganic filler has been introduced, an inorganic vapor deposition layer made of an inorganic compound having a thickness of 5 to 300 nm is provided. The adhesion between the material and the inorganic vapor deposition film can be improved. When the inorganic filler is present in the plastic substrate, irregularities are formed on the surface of the plastic substrate. By smoothing this with a transparent primer layer, an effect of maintaining barrier properties can be expected. As an effect of buffering external stress, in the resin layer in which the inorganic filler is introduced, there are fine pores at the boundary between the inorganic filler and the resin, and the pores absorb and relax the external stress. Can be reduced, cracks can be prevented from being introduced, and the barrier property can be maintained.

Embodiments of the present invention will be described below.
FIG. 1 is a cross-sectional view illustrating an example of a gas barrier laminate according to the present invention. A transparent primer layer 2, an inorganic vapor deposition layer 3, a composite coating layer 4, and a stress relaxation layer 5 are formed on the surface of the plastic substrate 1. The inorganic vapor-deposited layer 3, the composite coating layer 4, and the stress relaxation layer 5 may be formed on both surfaces of the substrate, or may be a layer in which the components of the composite coating layer 4 and the stress relaxation layer 5 are mixed. It may be.

(Plastic substrate 1)
The plastic substrate 1 in the present invention is preferably a transparent film substrate. Examples include polyester films such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), polyolefin films such as polyethylene and polypropylene, polystyrene films, polyamide films, polycarbonate films, polyacrylonitrile films, and polyimide films. Further examples include polyvinyl chloride, cellulose, triacetyl cellulose, polyvinyl alcohol, and polyurethanes. Materials having at least one or more of the above materials as components, having copolymer components, or having chemically modified compounds as components are also included. The substrate may be either stretched or unstretched, and preferably has mechanical strength and dimensional stability. Among these, a polyethylene terephthalate film or a polyamide film arbitrarily stretched in the biaxial direction is preferably used. Various known additives and stabilizers such as an antistatic agent, an anti-ultraviolet agent, a plasticizer, and a lubricant may be used on the surface of the substrate opposite to the surface on which the vapor deposition layer is provided.

  The thickness of the plastic substrate 1 is not particularly limited, and a film obtained by laminating films having different properties other than a single film can be used in consideration of suitability as a packaging material. In consideration of workability in forming the transparent primer layer 2, the inorganic vapor deposition layer 3, and the stress relaxation layer 5, the range of 3 to 200 μm is preferable, and the range of 6 to 30 μm is particularly preferable.

  An inorganic filler is contained in the plastic substrate 1. Examples of the inorganic filler used in the present invention include titanium oxide, calcium hydroxide, calcium carbonate, and barium sulfate. The weight percentage of the inorganic filler in the plastic substrate 1 is preferably 5 to 60%, more preferably 10 to 25%. If the filler concentration is less than 5%, the stress relaxation effect is insufficient, and if it exceeds 60%, uniform dispersion cannot be achieved and the substrate itself is colored by the filler.

(Transparent primer layer 2)
The transparent primer layer 2 in the present invention will be described in detail. The purpose of the transparent primer layer 2 is to improve the adhesion between the plastic substrate 1 and the inorganic vapor deposition layer 3 made of an inorganic compound.

  In order to achieve the above object, it is necessary to use a composite of a silane coupling agent or a hydrolyzate thereof, a polyol and an isocyanate compound, etc., as a primer resin.

  As an example of the silane coupling agent, a silane coupling agent containing an arbitrary organic functional group can be used, for example, ethyltrimethoxysilane, vinyltrimethoxysilane, γ-chloropropylmethyldimethoxysilane, γ-chloropropyl. Use one or more of silane coupling agents such as trimethoxysilane, glycidoxypropyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropylmethyldimethoxysilane or hydrolysates thereof. Can do.

  Further, among these silane coupling agents, those having a functional group that reacts with a hydroxyl group of a polyol or an isocyanate group of an isocyanate compound are particularly preferable. For example, those containing an isocyanate group such as γ-isocyanatopropyltriethoxysilane, γ-isocyanatopropyltrimethoxysilane, those containing a mercapto group such as γ-mercaptopropyltriethoxysilane, γ-aminopropyltriethoxysilane, Some include amino groups such as γ-aminopropyltrimethoxysilane, N-β- (aminoethyl) -γ-aminopropyltriethoxysilane, and γ-phenylaminopropyltrimethoxysilane. Furthermore, those containing an epoxy group such as γ-glycidoxypropyltrimethoxysilane and β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, vinyltrimethoxysilane, vinyl (β-methoxyethoxy) silane, etc. Such a silane coupling agent may be added with alcohol or the like and added with a hydroxyl group or the like, and one or more of these may be used.

  These silane coupling agents have a silane cup containing a functional group in which an organic functional group present at one end exhibits an interaction in a composite composed of a polyol and an isocyanic compound or reacts with a hydroxyl group of a polyol or an isocyanate group of an isocyanate compound. By using a ring agent, a stronger primer layer is formed by providing a covalent bond, and the silanol group formed by hydrolysis of the alkoxy group at the other end is a metal in the inorganic compound or the activity of the surface of the inorganic compound. High adhesiveness with an inorganic compound is expressed by a strong interaction with a high hydroxyl group and the like, and desired physical properties can be obtained. Therefore, you may use what hydrolyzed the said silane coupling agent with the metal alkoxide. In addition, there is no problem even if the alkoxy group of the silane coupling agent is a chloro group, an acetoxy group, etc., and these alkoxy groups, chloro groups, acetoxy groups, etc. are hydrolyzed to form silanol groups. Can be used in this composite.

  A polyol has two or more hydroxyl groups in a polymer and is reacted with an isocyanate group in an isocyanate compound added later. Among these, an acrylic polyol which is a polyol obtained by polymerizing an acrylic acid derivative monomer or a polyol obtained by copolymerizing an acrylic acid derivative monomer and other monomers is particularly preferable. Among these, those obtained by polymerizing acrylic acid derivative monomers such as ethyl methacrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, and hydroxylbutyl methacrylate alone, and acrylic polyols obtained by copolymerizing with other monomers such as styrene are preferably used. In consideration of the reactivity with the isocyanate compound, the hydroxyl value is preferably between 5 and 200 (KOHmg / g).

  The blending ratio of the polyol and the silane coupling agent is preferably in the range of 1/1 to 1000/1 in terms of weight ratio, more preferably in the range of 2/1 to 100/1. The dissolving and diluting solvent is not particularly limited as long as it can be dissolved and diluted. For example, esters such as ethyl acetate and butyl acetate, alcohols such as methanol, ethanol and isopropyl alcohol, ketones such as methyl ethyl ketone, Those in which aromatic hydrocarbons such as toluene and xylene are used alone and arbitrarily blended can be used. However, since an aqueous solution such as hydrochloric acid may be used to hydrolyze the silane coupling agent, it is preferable to use a solvent in which isopropyl alcohol or the like and ethyl acetate that is a polar solvent are arbitrarily mixed as a cosolvent.

Further, a reaction catalyst may be added in order to promote the reaction at the time of blending the silane coupling agent and the polyol. The catalyst to be added is a tin compound such as tin chloride (SnCl ₂ , SnCl ₄ ), tin oxychloride (SnOHCl, Sn (OH) ₂ Cl ₂ ), tin alkoxide and the like in terms of reactivity and polymerization stability. Is preferred. If the addition amount is too small or too large, the catalytic effect cannot be obtained, and therefore it is preferably in the range of 1/10 to 1/10000 in terms of molar ratio with respect to the trifunctional organosilane, more preferably 1 / 100 to 1/2000.

  The isocyanate compound to be mixed is added in order to enhance the adhesion between the base material and the inorganic vapor deposition layer by a urethane bond formed by reacting with a polyol, and mainly acts as a crosslinking agent or a curing agent. To achieve this, as isocyanate compounds, monomers such as aromatic tolylene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), aliphatic xylene diisocyanate (XDI), and hexadiisocyanate (HMDI); These polymers and derivatives are used, and these can be used alone or in combination of two or more.

  The blending ratio of the polyol and the isocyanate compound is not particularly limited, but if the amount of the isocyanate compound is too small, the curing may be poor, and if it is too much, blocking or the like occurs and there is a problem in processing. Therefore, as a blending ratio of the polyol and the insocyanate compound, the NCO group derived from the isocyanate compound is preferably 50 times or less of the OH group derived from the polyol, and particularly preferably, the NCO group and the OH group are blended in an equivalent amount. Is the case. As a mixing method, a known method can be used and is not particularly limited.

Furthermore, a metal alkoxide or a hydrolyzate thereof may be added in order to improve the liquid stability during preparation of the above mixture. This metal alkoxide is represented by the general formula M (OR) _n (M: metal element, R: alkyl group of CH ₃ , C ₂ H ₅ , n: oxidation number of metal element). Examples of the metal in the metal alkoxide or the hydrolyzate thereof include Si, Al, Ti, and Zr. In particular, tetraethoxysilane (Si (OC ₂ H ₅ ) ₄ ), tripropoxyaluminum (Al (OC ₃ ), and the like. H ₇ ) ₃ ), their hydrolysates, polymers or mixtures thereof are preferred because they are relatively stable in aqueous solvents. The metal alkoxide hydrolyzate may be hydrolyzed together with a silane coupling agent or may be added after an acid or the like is added alone.

  The transparent primer layer 2 is obtained by directly or previously hydrolyzing such a silane coupling agent or hydrolyzed together with a metal alkoxide (in this case, the above-mentioned reaction catalyst or the like may be added together) ) Is mixed with a polyol or an isocyanate compound, or a silane coupling agent and a polyol are mixed in advance in a solvent (at this time, the above-mentioned reaction catalyst and metal alkoxide are added together) Among those that have undergone a hydrolysis reaction, or just a mixture of a silane coupling agent and a polyol (in this case, it is possible to add the above-mentioned reaction catalyst and metal alkoxide together) An isocyanate compound is added to form a composite liquid and coated on the plastic substrate 1 To.

  Various additives such as tertiary amines, imidazole derivatives, carboxylic acid metal salt compounds, quaternary ammonium salts, quaternary phosphonium salts and other curing accelerators, phenolic, sulfur-based, phosphite-based compounds. It is also possible to add an antioxidant, a leveling agent, a flow regulator, a catalyst, a crosslinking reaction accelerator, a filler and the like.

  The thickness of the transparent primer layer 2 is not particularly limited as long as a uniform coating film can be formed, but is generally preferably in the range of 0.001 to 2 μm. When the thickness is less than 0.001 μm, it is difficult to obtain a uniform coating film, and the adhesion may be lowered. On the other hand, when the thickness exceeds 2 μm, the coating film cannot be kept flexible because it is thick, and the coating film may be cracked due to external factors, which is not preferable. Particularly preferred is a range of 0.03 to 0.5 μm.

  As a method for forming the transparent primer layer 2, for example, a known printing method such as an offset printing method, a gravure printing method, a silk screen printing method, or a known coating method such as roll coating, knife edge coating, or gravure coating may be used. it can. About drying conditions, generally used conditions may be used. In order to accelerate the reaction, it can be left in a high-temperature aging chamber for several days.

(Inorganic vapor deposition layer 3)
In general, the thickness of the inorganic vapor deposition layer 3 is desirably in the range of 5 to 300 nm, and the value is appropriately selected. However, if the film thickness is less than 5 nm, a uniform film may not be obtained or the film thickness may not be sufficient, and the function as a gas barrier material may not be sufficiently achieved. Further, when the film thickness exceeds 300 nm, the thin film cannot be kept flexible, and there is a problem because the thin film may be cracked due to external factors such as bending and pulling after the film formation. More preferably, it exists in the range of 10-150 nm.

  Examples of the inorganic vapor deposition layer 3 include vapor deposition films such as silicon oxide, aluminum oxide, and magnesium oxide. There are various methods for forming the inorganic vapor-deposited layer 3 on the plastic substrate 1, and it can be formed by a normal vacuum vapor deposition method. In addition, other thin film forming methods such as sputtering, ion plating, and plasma vapor deposition (CVD) can also be used. However, in view of productivity, the vacuum deposition method is the best at present. It is preferable to use one of an electron beam heating method, a resistance heating method, and an induction heating method as a heating means of the vacuum evaporation method, but an electron beam heating method should be used in consideration of the wide selection of evaporation materials. Is more preferable. Moreover, in order to improve the adhesiveness of a vapor deposition thin film layer and a base material, and the denseness of a vapor deposition thin film layer, it is also possible to vapor-deposit using a plasma assist method or an ion beam assist method.

(Composite coating layer 4)
The composite coating layer 4 in the present invention will be described. The composite coating layer 4 is a coating layer having gas barrier properties, and is mainly composed of an aqueous solution or water / alcohol mixed solution containing a water-soluble polymer and one or more metal alkoxides, hydrolysates thereof and / or polymers thereof. It is formed using a coating agent. For example, a water-soluble polymer dissolved in an aqueous (water or water / alcohol mixed) solvent mixed with a metal alkoxide treated directly or previously hydrolyzed (mixing ratio 4: 6) Into a solution. After coating this solution on the inorganic vapor deposition layer 3 which consists of a metal or an inorganic oxide, it heat-drys and forms. Each component contained in the coating agent will be described in more detail.

  Examples of the water-soluble polymer in the present invention include polyvinyl alcohol, polyvinyl pyrrolidone, starch, methyl cellulose, carboxymethyl cellulose, and sodium alginate. In particular, when polyvinyl alcohol (hereinafter abbreviated as PVA) is used for the coating agent of the present invention, the gas barrier property is most excellent, which is preferable. PVA here is generally obtained by saponifying polyvinyl acetate. As PVA, for example, complete PVA in which only several percent of acetic acid groups remain can be used from so-called partially saponified PVA in which several tens percent of acetic acid groups remain, and other types may be used. .

The metal alkoxide is a compound represented by a general formula, M (OR) _n (M: metal such as Si, Ti, Al, Zr, R: alkyl group such as R ₃ CH ₃ , C ₂ H ₅ ). Specifically, M is preferably Si, Al or a mixture thereof, such as tetraethoxysilane (Si (OC ₂ H ₅ ) ₄ ), tripropoxyaluminum (Al (OC ₃ H ₇ ) ₃ ), etc. Ethoxysilane and triisopropoxyaluminum are preferable because they are relatively stable in an aqueous solvent after hydrolysis.
In addition, since the composite film layer 4 made of a mixture of a metal alkoxide and a water-soluble polymer is made of hydrogen bonds, it may swell and dissolve in water. In order to prevent this, it is preferable to add a silane coupling agent to the metal alkoxide.

  It is also possible to add known additives such as isocyanate compounds, silane coupling agents, or dispersants, stabilizers, viscosity modifiers, and colorants to the solution as long as the gas barrier properties are not impaired. is there.

  As a method for applying the coating agent, conventionally known methods such as a dipping method, a roll coating method, a screen printing method, a spray method, and a gravure printing method that are usually used can be used.

  The thickness of the composite coating layer varies depending on the optimum conditions depending on the type of coating agent, the processing machine and the processing conditions, and is not particularly limited. However, when the thickness after drying is 0.01 μm or less, a uniform coating film cannot be obtained and sufficient gas barrier properties may not be obtained. On the other hand, if the thickness exceeds 50 μm, cracks are likely to occur in the film, which may be a problem. It is preferably in the range of 0.01 to 50 μm, more preferably in the range of 0.1 to 10 μm.

(Stress relaxation layer 5)
Next, the stress relaxation layer 5 in the present invention will be described. The stress relaxation layer 5 is formed using a coating agent having an appropriate composition for forming a film while including an inorganic filler. For example, an inorganic filler is kneaded with a resin component made of urethane or the like, and mixed with an organic solvent in order to have a viscosity suitable for coating. After coating this solution on the inorganic vapor deposition layer which consists of an inorganic compound, it heat-drys and forms. The inorganic filler component contained in the coating agent will be described in more detail.

  Examples of the inorganic filler used in the stress relaxation layer 5 include titanium oxide, calcium hydroxide, calcium carbonate, barium sulfate, and silicon oxide. It is pulverized to be well dispersed in the coating solution. 5-60% is preferable and, as for the weight% of the inorganic filler in the stress relaxation layer 5, 10-25% is more preferable. If the inorganic filler concentration is less than 5%, the effect of buffering the retort impact is insufficient. If it exceeds 60%, uniform dispersion cannot be achieved, and the coating itself is colored by the filler.

  As a method for applying the coating agent, conventionally known methods such as a dipping method, a roll coating method, a screen printing method, a spray method, and a gravure printing method that are usually used can be used.

  The thickness of the stress relaxation layer 5 varies depending on the optimum conditions depending on the type of coating agent, the processing machine, and the processing conditions, and is not particularly limited. However, when the thickness after drying is 0.01 μm or less, a uniform coating film cannot be obtained and sufficient gas barrier properties may not be obtained. On the other hand, if the thickness exceeds 50 μm, cracks are likely to occur in the film, which may be a problem. It is preferably in the range of 0.01 to 50 μm, more preferably in the range of 0.1 to 10 μm.

  Examples of the present invention will be specifically described below. The present invention is not limited to these examples.

<Example 1>
Preparation of Composite Solution 2- (Epoxycyclohexyl) ethyltrimethoxysilane (hereinafter abbreviated as EETMS) and acrylic polyol are mixed in a dilution solvent by 5.0 times (weight ratio) with respect to EETMS, and tin chloride is further used as a catalyst. Add (SnCl ₂ ) / methanol solution (prepared to 0.003 mol / g) to 1/135 mol with respect to EETMS and stir. Next, a mixed solution obtained by diluting a mixed solution of tolylene diisocyanate (hereinafter abbreviated as TDI) as an isocyanate compound so that NCO groups are equivalent to OH groups of the acrylic polyol to an arbitrary concentration is referred to as a composite solution A.

  The composite solution A as a transparent primer layer was formed to a thickness of 0.2 μm on one side of a base material containing 20 wt% of silicon oxide in a polyethylene naphthalate (PEN) film having a thickness of 12 μm as a plastic substrate. Next, an inorganic vapor deposition layer made of an inorganic oxide having a thickness of 20 nm was formed on the transparent primer layer by evaporating silica using a resistance heating type vacuum vapor deposition apparatus. Furthermore, a coating agent having the following composition was applied thereon with a bar coater and dried at 120 ° C. for 1 minute with a dryer to form a 0.3 μm thick composite coating layer. On the composite coating layer, the following A A liquid was prepared, applied and dried by a gravure coating method, a 1 μm-thick stress relaxation layer was formed, and a gas barrier laminate was prepared.

  Liquid A: A solution obtained by kneading urethane resin and barium sulfate and diluting with an organic solvent (isopropyl alcohol: methyl ethyl ketone: toluene = 1: 3: 2). The barium sulfate component ratio in the stress relaxation layer was 20 wt%.

Coating agent for the composite coating layer: 89 g of hydrochloric acid (0.1 N) added to 10 g of tetraethoxysilane, and stirred for 30 minutes to hydrolyze, a hydrolyzed solution with a solid content of 3 wt% (in terms of SiO ₂ ), and 3 wt% of polyvinyl alcohol A water / isopropyl alcohol solution (water: isopropyl alcohol = 90: 10 weight ratio) was mixed (mixing ratio 6: 4) to obtain.

<Example 2>
A gas barrier laminate was produced in the same manner as in Example 1 except that the silicon oxide content ratio in the plastic substrate was 10 wt%.

<Comparative Example 1>
A gas barrier laminate was produced in the same manner as in Example 1 except that the silicon oxide content ratio in the plastic substrate was 1 wt% or less.

<Comparative example 2>
A gas barrier laminate was produced in the same manner as in Example 1 except that the silicon oxide content ratio in the plastic substrate was 1 wt% or less and no stress relaxation layer was provided.

  Further, a three-layer laminated sample of PVF film (25 μm) / gas barrier laminate / PVF film (25 μm) was prepared by dry lamination using a two-component curable polyurethane adhesive.

<Evaluation 1>
As a severe environment test of the laminated sample, a pressure cooker test (PCT) (a severe environment test by high temperature and high pressure) was carried out at 105 ° C. for 92 hours. The oxygen permeability after this treatment was measured in a 30 ° C.-70% RH atmosphere using Modern Control (MOCON OXTRAN 10 / 50A).
The results are shown in Table 1.

<Evaluation 2>
The laminate strength between the vapor deposition film / PVF film of the laminated sample after the PCT was measured using an Orientec Tensilon universal tester RTC-1250 (conforms to JIS Z1707). However, the measurement was performed while the measurement site was wetted with water. The results are shown in Table 1.

  Since the gas barrier laminate of the present invention has the characteristics that the propagation of external stress to the barrier layer is eased and the performance is not deteriorated even by the compression / expansion stress due to the environmental change, it is used in various industrial materials fields, particularly for solar cell backsheets. Useful.

It is sectional drawing of an example of the gas barrier laminated body of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Plastic base material 2 Transparent primer layer 3 Inorganic vapor deposition layer 4 Composite coating layer 5 Stress relaxation layer

Claims (8)

On at least one surface of the plastic substrate containing 5 to 60% by weight of the inorganic filler,
An inorganic vapor deposition layer having a thickness of 5 to 300 nm;
A gas barrier laminate comprising a stress relaxation layer containing 5 to 60% by weight of an inorganic filler, which is sequentially laminated.   The transparent primer layer which consists of a composite of a silane wrapping agent or its hydrolyzate, a polyol, and an isocyanate compound between the said plastic substrate and the said inorganic vapor deposition layer is characterized by the above-mentioned. Gas barrier laminate.   A composite coating layer containing a water-soluble polymer compound and at least one selected from a metal alkoxide, a hydrolyzate thereof and a polymer thereof is provided between the inorganic vapor deposition layer and the stress relaxation layer. The gas barrier laminate according to claim 1 or 2.   The gas barrier laminate according to claim 2 or 3, wherein the silane coupling agent or a hydrolyzate thereof includes a functional group that reacts with at least one of a hydroxyl group of a polyol and an isocyanate group of an isocyanate compound. In the composite, at least one kind selected from tetraethoxysilane (Si (OC ₂ H ₅ ) ₄ ), tripropoxyaluminum (Al (OC ₃ H ₇ ) ₃ ), a hydrolyzate thereof, and a polymer thereof. The gas barrier laminate according to any one of claims 2 to 4, which is added.   The gas barrier laminate according to any one of claims 2 to 5, wherein the transparent primer layer has a thickness in the range of 0.001 to 2 µm.   The gas-barrier laminate according to any one of claims 3 to 6, wherein the water-soluble polymer compound contains at least polyvinyl alcohol.   The gas barrier laminate according to any one of claims 3 to 7, wherein the metal in the metal alkoxide or the hydrolyzate of the metal alkoxide is Si, Al, or a mixture thereof.

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