JP2007196550A - Gas barrier film laminate resistant to heat treatment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a gas barrier film laminate having resistance to heat treatment which causes no delamination and also prevents the gas barrier properties from deteriorating even if the heat treatment in heat sterilization processing and the like, such as boiling and retort, is carried out with the adhesion strengthened between a base material consisting of a plastic material and a vapor deposition thin film layer consisting of an inorganic substance and in gas barrier properties. <P>SOLUTION: At least one surface of the base material consisting of the plastic material is provided with pretreatment by reactive ion etching utilizing plasma. The pre-treated surface by this pretreatment is overlaid successively with the vapor deposition thin film layer consisting of the inorganic substance and the gas barrier film layer that is formed by heat drying a thin film consisting of a mixed solution containing at least a silicone compound represented by Si(OR<SP>1</SP>)<SB>4</SB>and R<SP>2</SP>Si(OR<SP>3</SP>)<SB>3</SB>(wherein R<SP>1</SP>and R<SP>3</SP>are a hydrolyzable group and R<SP>2</SP>is an organic functional group) or its hydrolysate and a water-soluble polymer having a hydroxyl group. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a gas barrier film laminate in which the deterioration of the barrier property that is present before the treatment is small and the adhesion is not lowered even when the heat treatment is performed in heat sterilization or cooking. More specifically, it can be suitably used as a constituent material of a packaging body such as a packaging bag or a packaging container subjected to heat sterilization treatment such as boil sterilization or retort sterilization, or heat treatment in retort cooking. The present invention relates to a gas barrier film laminate.

  In recent years, packaging materials used for packaging foods and pharmaceuticals have oxygen, water vapor, and other contents that alter the contents so that they can retain their functions and properties by suppressing the alteration of the contents that are packaged. It is required to have a gas barrier property for blocking the above. Therefore, conventionally, packaging materials using a metal foil made of aluminum or the like, which is less affected by temperature, humidity, etc., as a gas barrier layer have been widely used.

  However, a packaging material using a metal foil such as aluminum has a high gas barrier property, which can reduce the influence on the temperature and humidity of the contents to be packaged. It has disadvantages such that it cannot be confirmed, it must be treated as an incombustible material when discarded after use, and a metal detector cannot be used for inspection.

  Therefore, in order to overcome these disadvantages, vapor deposition is performed by laminating a vapor deposition thin film made of an inorganic oxide such as silicon oxide or aluminum oxide on a substrate made of a plastic material by a thin film forming means such as a vacuum vapor deposition method or a sputtering method. A film has been developed (see, for example, Patent Documents 1 and 2). These vapor-deposited films are known to have transparency and gas barrier properties against oxygen, water vapor, etc., and packaging with transparency and gas barrier properties that cannot be obtained with packaging materials that use metal foil as a gas barrier layer. It is suitably used as a material.

  However, since the vapor deposition film described above has not been subjected to pretreatment for ensuring adhesion with the base material, the adhesion between the base material and the vapor deposition thin film is weak, and heat sterilization treatment such as boil / retort treatment or heating There is a drawback that delamination is likely to occur when cooking is performed.

  In order to solve this problem, it has been conventionally practiced to improve the adhesion with a deposited thin film by performing a plasma treatment on a plastic substrate in-line when producing a deposited film.

  However, when performing plasma processing in-line, in a plasma processing machine, an electrode for applying a voltage for generating plasma is installed on a side other than the drum side on which the base is set, and the base is Since it is arranged on the anode side, a high self-bias cannot be obtained, and as a result, it has been difficult to perform the plasma treatment so that the desired adhesion can be expressed. When processing with a high self-bias, the DC discharge method can be used, but in order to obtain a high bias voltage with this method, the plasma mode changes from glow to arc. It is not possible to perform uniform processing.

On the other hand, a water-soluble polymer having a hydroxyl group as a second layer on a vapor-deposited thin film made of an inorganic oxide for the purpose of imparting post-processing appropriateness to the vapor-deposited film as described above and ensuring gas barrier properties. And a coating agent mainly comprising an aqueous solution containing at least one of metal alkoxide or metal alkoxide hydrolyzate or tin chloride, or a hydroalcoholic mixed solution, and a gas barrier film formed by heating and drying is laminated. Such a proposal has been made (for example, see Patent Document 3).

However, since the second coating layer of the gas barrier film is composed of hydrogen bonds between a hydrolyzed metal alkoxide and a water-soluble polymer having a hydroxyl group, it swells when subjected to heat treatment, for example, during boil / retort sterilization. As a result, the barrier properties possessed before the heat treatment deteriorate. Moreover, it becomes easy to generate | occur | produce a crack in the vapor deposition thin layer which consists of inorganic oxides by swelling, and it has also become a cause by which barrier property deteriorates further.
U.S. Pat. No. 3,442,686 Japanese Patent Publication No.63-28017 Japanese Patent Laid-Open No. 7-164591

  The present invention has been made to solve the above-mentioned problems, and strengthens the adhesion and gas barrier properties of a base material made of a plastic material and a vapor-deposited thin film layer made of an inorganic oxide, and heat sterilization treatment such as boiling and retort. Another object of the present invention is to provide a gas barrier film laminate having heat treatment resistance that does not cause delamination even when heat treatment in heat cooking is performed, and also prevents deterioration of gas barrier properties.

In order to achieve the above object, according to the first aspect of the present invention, at least one surface of a base material made of a plastic material is pretreated by reactive ion etching (RIE) using plasma. On the pretreated surface by RIE, a vapor-deposited thin film layer made of an inorganic oxide, Si (OR ¹ ) ₄ and R ² Si (OR ³ ) ₃ (R ¹ and R ³ are hydrolyzable groups, R ² is an organic functional group.) A gas barrier coating layer formed by heating and drying a thin film made of a mixed solution containing at least a silicon compound represented by (1) or a hydrolyzate thereof, and a water-soluble polymer having a hydroxyl group; Is a gas barrier film laminate having heat treatment resistance, characterized by being sequentially laminated.

The invention according to claim 2 is the gas barrier film laminate having heat treatment resistance according to claim 1, wherein the hydrolyzable group (R ¹ ) of Si (OR ¹ ) ₄ is C ₂ H _5. It is characterized by.

Furthermore, the invention according to claim 3 is the gas barrier film laminate having heat treatment resistance according to claim 1 or 2, wherein the organic functional group (R ² ) of R ² Si (OR ³ ) ₃ is vinyl, It is a non-aqueous functional group such as epoxy, methacryloxy, ureido, and isocyanate.

Furthermore, the invention according to claim 4 is the gas barrier film laminate having heat treatment resistance according to claim 3, wherein the organic functional group (R ² ) is γ-glycidoxypropyl group or β- (3, 4 epoxy cyclohexyl) group.

Furthermore, the invention according to claim 5 is the gas barrier film laminate having heat treatment resistance according to any one of claims 1 to 4, wherein Si (OR ¹ ) _{4 is changed} to SiO ₂ , and R ² Si (OR
³⁾ ₃ when converted into R ² Si (OH) _3, wherein the solid content of the R ² Si (OH) ₃ is 1 to 50% by weight relative to the total solids content.

Furthermore, the invention according to claim 6 is the gas barrier film laminate having heat treatment resistance according to any one of claims 1 to 5, wherein Si (OR ¹ ) _{4 is changed} to SiO ₂ , and R ² Si (OR ³ ) When ₃ is converted to R ² Si (OH) ₃ , the blending ratio of the solid content is SiO ₂ / (R ² Si (OH) ₃ / water-soluble polymer) = 100/100 to 100/30 in weight ratio. It is within the range.

  Furthermore, the invention according to claim 7 is the gas barrier film laminate having heat treatment resistance according to any one of claims 1 to 6, wherein the plastic material is polyethylene, polypropylene, polyamides, polyesters, polycarbonates, polycarbonates. It is characterized by having at least one of acrylonitrile, polystyrene, polyvinyl chloride, polyvinyl alcohol and polyurethane as a component or having a copolymer component.

  Furthermore, the invention according to claim 8 is the gas barrier film laminate having heat treatment resistance according to claim 7, wherein the polyesters are polyethylene terephthalate, polyethylene naphthalate, boribylene terephthalate, boribylene naphthalate and co-polymers thereof. It is a polymer.

  Furthermore, the invention according to claim 9 is the gas barrier film laminate having heat sterilization resistance according to any one of claims 1 to 8, wherein the inorganic oxide is aluminum oxide, silicon oxide or a mixture thereof. It is characterized by that.

  The gas barrier film laminate having the heat treatment resistance of the present invention has a high gas barrier property, and the barrier property possessed before the treatment is not deteriorated even after the heat treatment such as boil and retort, and the adhesion property Delamination is less likely to occur. Therefore, it is possible to provide a packaging material for packaging various contents such as retort foods, pharmaceuticals, and electronic components by performing post-processing such as printing, dry lamination, melt extrusion lamination, and thermocompression lamination. It becomes possible.

  Hereinafter, the best embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 1 is an explanatory view showing a schematic cross-sectional configuration of a gas barrier film laminate having heat treatment resistance according to the present invention. In this gas barrier film laminate, pretreatment by reactive ion etching (RIE) using plasma is performed on at least one surface of a base material 1 made of a plastic material. Includes an evaporated thin layer 2 made of an inorganic oxide, Si (OR ¹ ) ₄ and R ² Si (OR ³ ) ₃ (R ¹ and R ³ are hydrolyzable groups, and R ² is an organic functional group. And a gas barrier coating layer 3 formed by heating and drying a thin film made of a mixed solution containing at least a silicon compound or a hydrolyzate thereof and a water-soluble polymer having a hydroxyl group. is there.

The substrate 1 is made of a plastic material, and is preferably a transparent film substrate if possible in order to make use of the transparency of the deposited thin film layer 2 made of an inorganic oxide. Examples of the substrate 1 include polyester films made of polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), polyolefin films made of polyethylene, polypropylene, etc., polystyrene films, polyamide films, polycarbonate films, polyacrylonitrile films, polyimides A film etc. are mentioned. These films may be stretched or unstretched, but those having excellent mechanical strength and dimensional stability are preferred. Among these, a polyethylene terephthalate film or a polyamide film arbitrarily stretched in the biaxial direction is preferably used.

  On the surface of the substrate 1 opposite to the surface on which the deposited thin film layer 2 is provided, a thin film made of various known additives and stabilizers such as an antistatic agent, an ultraviolet ray preventing agent, a plasticizer, and a lubricant. May be provided.

  Although the thickness of the base material 1 is not particularly limited, in consideration of workability in the case of laminating a primer layer, a vapor-deposited thin film layer made of an inorganic oxide, a gas barrier film layer, etc., which will be described later, it is practical. What is necessary is just to exist in the range of 3-200 micrometers. More preferably in the range of 6-30 μm. In consideration of suitability as a packaging material, the layer structure may be a single layer structure or a multilayer structure of films having different properties.

  In order to reinforce the adhesion between the substrate 1 and the vapor-deposited thin film layer 2 made of an inorganic oxide, the surface of the substrate 1 is subjected to a pretreatment by reactive ion etching (RIE) using plasma. By performing this pretreatment by RIE, the surface of the base material 1 made of a plastic material is given a functional group using radicals and ions generated at that time, and the surface is ion-etched to remove impurities and smooth the surface. Can be realized. By performing such surface treatment, a dense vapor-deposited thin film of inorganic oxide can be formed on the pretreatment surface 4. As a result, the adhesion between the base material 1 and the deposited thin film layer 2 is strengthened, leading not only to improvement of gas barrier properties and prevention of cracks, but also delamination hardly occurs even when heat treatment such as retort is performed. .

  Next, the vapor deposition thin film layer 2 made of an inorganic oxide will be described in detail. The vapor-deposited thin film layer 2 made of an inorganic oxide is made of a vapor-deposited thin film of an inorganic oxide such as aluminum oxide, silicon oxide, tin oxide, magnesium oxide, or a mixture thereof, and has transparency and resists oxygen, water vapor, etc. It is a layer having gas barrier properties. In consideration of securing heat treatment resistance against various heat treatments, aluminum oxide and silicon oxide are more preferably used among these constituent materials. However, the deposited thin film layer 2 is not limited to those composed of these inorganic oxides, and may be formed of other inorganic oxides that meet the above conditions.

  The optimum value of the thickness of the vapor-deposited thin film layer 2 varies depending on the type and configuration of the inorganic oxide used, but it is generally desirable that the thickness be in the range of 5 to 300 nm. If the film thickness is less than 5 nm, it may be difficult to obtain a uniform thin film or it may be difficult to ensure gas barrier properties. On the other hand, if the film thickness exceeds 300 nm, it becomes difficult to maintain flexibility in the thin film, and there is a risk that cracks may occur due to external factors such as bending and pulling after film formation. More preferably, it should just exist in the range of 10-150 nm.

  As a method for forming the deposited thin film layer 2 made of inorganic oxide on the substrate 1, thin film forming means such as a vacuum deposition method, a sputtering method, an ion plating method, a plasma vapor deposition method (CVD) or the like is employed. be able to. However, considering productivity, the vacuum deposition method is the best at present. As a heating means in the vacuum evaporation method, it is preferable to use any one of an electron beam heating method, a resistance heating method, and an induction heating method, but in consideration of the wide selection of evaporation materials, the electron beam heating method is used. Is more preferable. In order to improve the adhesion between the deposited thin film layer and the substrate and the denseness of the deposited thin film layer, it is also possible to form the deposited thin film using a plasma assist method or an ion beam assist method. Further, in order to increase the transparency of the deposited thin film layer, it is possible to use reactive deposition performed by blowing various gases such as oxygen.

Next, the gas barrier coating layer 3 will be described in detail. This gas barrier coating layer 3 is
Provided by laminating on the above-described vapor-deposited thin film layer 2 so as to prevent the deterioration of the barrier property even in use under severe use conditions due to the synergistic effect of the laminated structure with the vapor-deposited thin film layer 2 It is a gas barrier coating.

  As this type of gas barrier coating, as described above, a water-soluble polymer having a hydroxyl group and one or more types of metal alkoxide or metal alkoxide hydrolyzate or chloride formed on a vapor-deposited thin film made of an inorganic oxide. There is a gas barrier film formed by heating and drying a thin film made of a coating agent mainly containing an aqueous solution containing at least one of tin or a hydroalcoholic mixed solution. However, since such a condensate film is easily cracked due to distortion due to volume reduction during condensation, it is very difficult to provide a thin and uniform film on the film. By adding a polymer to the coating agent, flexibility can be imparted to the thin film so that cracks do not occur. However, a thin film formed with a coating agent to which a polymer is added appears to be uniform visually, but it is often microscopically separated into a metal oxide and a polymer portion, and thus has a barrier property. In such packaging materials, it may become a so-called barrier hole. For this, a polymer having a hydroxyl group is added, and a strong hydrogen bond between the hydroxyl group of the polymer and the hydrolyzate of the metal alkoxide is used to condense the metal oxide with the polymer during condensation. It is possible to make the coating exhibit a high barrier property close to that of ceramic.

  However, since the gas barrier coating layer composed of a metal alkoxide or a hydrolyzate thereof and a coating agent of a water-soluble polymer having a hydroxyl group is formed by hydrogen bonding, it swells and dissolves in water. In short, even if there is a synergistic effect due to the laminated structure of the deposited thin film layer and the gas barrier coating layer, it is difficult to maintain the initial gas barrier property under severe processing such as retort and boil processing.

Therefore, in the present invention, Si (OR ¹ ) ₄ and R ² Si (OR ³ ) ₃ (R ¹ and R ³ are hydrolyzable groups, and R ² is an organic functional group as materials constituting the gas barrier coating layer. Gas barrier coating layer 3 formed by heating and drying a thin film made of this mixed solution, using a mixed solution containing at least a silicon compound represented by the following formula: or a hydrolyzate thereof and a water-soluble polymer having a hydroxyl group. Is deposited on the vapor-deposited thin film layer 2 made of an inorganic oxide to eliminate the problem described above.

That is, the swelling of the gas barrier coating layer 3 can be prevented by adding the silicon compound represented by R ² Si (OR ³ ) ₃ or a hydrolyzate thereof as described above. In short, R ² Si (OR ³ ) ₃ is less likely to be a barrier hole because of its hydrolyzable group, forming a hydrogen bond with Si (OR ¹ ) ₄ and a water-soluble polymer. By creating a network, the group can prevent swelling of hydrogen bonds, and even when heat treatment is performed in heat sterilization or heat cooking, it makes it difficult for gas barrier properties to deteriorate. Among them, those having a vinyl group, an epoxy group, a methacryloxy group, a ureido group, and an isocyanate group are further improved in water resistance because the functional group is hydrophobic.

In the above mixed solution, when Si (OR ¹ ) ₄ is converted to SiO ₂ and R ² Si (OR ³ ) ₃ is converted to R ² Si (OH) ₃ , the solid content of R ² Si (OR ³ ) ₃ is It is desirable to be 1 to 50% by weight based on the total solid content. If it is less than 1% by weight, the water resistance effect is lowered, and if it exceeds 50% by weight, the functional group tends to be a pore of the barrier. Considering more reliable securing of resistance to heat treatment such as boil and retort sterilization treatment and gas barrier properties, it is more preferably 5 to 30% by weight.

Further, when Si (OR ¹ ) ₄ is converted to SiO ₂ and R ² Si (OR ³ ) ₃ is converted to R ² Si (OH) ₃ , the mixing ratio of the solid content is SiO ₂ / (R ² Si (OH) ₃ / water-soluble polymer) = 1
If it is in the range of 00/100 to 100/30, not only resistance to heat treatment and gas barrier properties in boil / retort sterilization treatment, etc., but also sufficient flexibility is provided when considering use as a packaging material. This is preferable because it is ensured.

Further, in Si (OR ¹ ) ₄ in the gas barrier coating layer 3, the hydrolyzable group (R ¹ ) can be expressed by CH ₃ , C ₂ H 5, C ₂ H ₄ OCH ₃ or the like. Can also be used. Among these, tetraethoxysilane is preferable because it is relatively stable in an aqueous solvent after hydrolysis.

  As the water-soluble polymer having a hydroxyl group in the gas barrier coating layer, polyvinyl alcohol, starch and celluloses are preferably used. In particular, when polyvinyl alcohol (hereinafter referred to as PVA) is used, the gas barrier property is most excellent. This is because PVA is a polymer containing the most hydroxyl groups in the monomer unit and therefore has a very strong hydrogen bond with the hydroxyl groups of the metal alkoxide after hydrolysis. PVA as used herein is generally obtained by saponifying polyvinyl acetate, and saponification is complete saponification in which only several percent of acetic acid groups remain from so-called partially saponified PVA in which several tens of percent of acetic acid groups remain. Includes up to PVA. The molecular weight of PVA has various degrees of polymerization ranging from 300 to several thousand, but any molecular weight may be used in the present invention. However, generally high molecular weight PVA having a high saponification degree and a high polymerization degree is preferably used because of its high water resistance.

In addition, when tetraethoxysilane is used as Si (OR ¹ ) _{4 and} PVA is used as the water-soluble polymer, metal oxidization when a metal alkoxide or a hydrolyzate of metal alkoxide is converted into a metal oxide (for example, SiO ₂ ) is used. weight ratio of the object and a water-soluble polymer _is more preferably SiO 2 / PVA is 100 / 10-100 / 100. When the PVA is less than 100/10, the gas barrier coating layer becomes hard, is liable to crack, the flexibility is lowered, and the gas barrier property is liable to deteriorate. Moreover, when PVA exceeds 100/100, it may cause water resistance inhibition.

In the preparation of the above mixed solution, the above description is applied regardless of the order of mixing the hydrolyzed Si (OR ¹ ) ₄ , the water-soluble polymer having a hydroxyl group, and R ² Si (OR ³ ) ₃ . Such a desired effect is manifested, but the method of separately hydrolyzing Si (OR ¹ ) ₄ and R ² Si (OR ³ ) ₃ and then adding it to the water-soluble polymer involves the fine dispersion of SiO ₂ and Considering the hydrolysis efficiency of Si (OR ¹ ) ₄ , this is a desirable method.

  Furthermore, the mixed solution considers the adhesion and wettability with the printing ink and adhesive used in the post-processing step to the gas barrier film laminate of the present invention, and also prevents the occurrence of cracks due to shrinkage of each constituent layer In addition, known additives such as isocyanate compounds, clay minerals such as colloidal silica and smectite, stabilizers, colorants, viscosity modifiers, etc. may be added as appropriate within a range that does not impair gas barrier properties and water resistance. .

  The thickness of the gas barrier coating layer 3 is not particularly limited. However, when the thickness after heat drying is less than 0.01 μm, it is difficult to obtain a uniform thin film layer, and sufficient gas barrier properties may not be obtained. On the other hand, when the thickness exceeds 50 μm, cracks are likely to occur in the thin film layer, which may be a problem. Preferably it may be in the range of 0.01 to 50 μm, more preferably in the range of 0.1 to 10 μm.

  Examples of the method for forming the gas barrier coating layer 3 on the deposited thin film layer 2 include dipping, roll coating, gravure coating, reverse coating, air knife coating, comma coating, die coating, screen printing, spray coating, and gravure offset printing. Can be adopted.

  The outline of the gas barrier film laminate having heat treatment resistance according to the present invention has been described above. However, the present invention is not limited to this, and a printing layer, an intervening film, and a sealant are formed on the gas barrier coating layer 3 described above. Layers and the like can be laminated in a post-processing step to form a packaging material.

  The intervening film is provided to increase the bag breaking strength and piercing strength required when used as a packaging material constituting a bag-shaped package, etc., and generally has mechanical strength and thermal stability. To biaxially stretched nylon film, biaxially stretched polyethylene terephthalate film, biaxially stretched polypropylene film and the like. The thickness is determined according to the material and the required quality, but generally may be in the range of 10 to 30 μm.

  Further, the sealant layer is a layer provided to serve as an adhesive layer when used as a packaging material for forming a bag-like package, such as polyethylene, polypropylene, ethylene-vinyl acetate copolymer, ethylene- It is constituted by a resin such as a methacrylic acid copolymer, an ethylene-methacrylic acid ester copolymer, an ethylene-acrylic acid copolymer, an ethylene-acrylic acid ester copolymer, and a metal cross-linked product thereof. The thickness is determined according to the purpose, but generally may be in the range of 15 to 200 μm.

  In the present invention, a printing layer, an intervening film, a sealant layer, and the like can be laminated on the surface on which the vapor-deposited thin film layer 2 and the gas barrier coating layer 3 are not laminated, if necessary. In addition, pretreatment by reactive ion etching (RIE) using the plasma described above is performed on both surfaces of the base material, and the above-described vapor deposition thin film layer and gas barrier coating layer are formed on the pretreatment surface formed by this pretreatment. You may make it laminate | stack. Further, the deposited thin film layer and the gas barrier coating layer may have a multilayer structure.

  Examples of the gas barrier film laminate having heat treatment resistance according to the present invention will be described below. The present invention is not limited to these examples.

  Reactive ion etching (RIE) is used on one side of a 12 μm thick polyethylene terephthalate (PET) film with an applied power of 120 W, a processing time of 0.1 sec, a processing gas of argon, and a processing unit pressure of 2.0 Pa. The plasma pretreatment was performed. At this time, a high frequency power source having a frequency of 13.56 MHz was used for the electrodes.

  Subsequently, a vacuum deposition apparatus using an electron beam heating method is used on the pre-processed surface by RIE provided by the above process, and a thin film of metal aluminum is evaporated while oxygen gas is introduced into the vacuum deposition apparatus. A deposited thin film made of aluminum oxide was formed. Next, a mixed solution prepared by mixing A liquid, B liquid, and C liquid shown below so that the blending ratio (wt%) is 70/20/10 is applied onto the deposited thin film layer by a gravure coating method, and is dried by heating. A gas barrier film layer having a thickness of 0.3 μm was formed to produce a gas barrier film laminate having heat sterilization resistance according to Example 1.

<Liquid A>
Hydrolysis solution having a solid content of 5 wt% (in terms of SiO ₂ ) obtained by adding 72.1 g of hydrochloric acid (0.1N) to 17.9 g of tetraethoxysilane and 10 g of methanol, followed by stirring for 30 minutes for hydrolysis.

<Liquid B>
5 wt% water / methanol solution of polyvinyl alcohol (water / methanol weight ratio = 95/5).

<C liquid>
Hydrochloric acid (1N) is gradually added to β- (3,4 epoxycyclohexyl) trimethoxysilane and isopropyl alcohol (IPA solution), and the mixture is stirred for 30 minutes for hydrolysis, and then hydrolyzed with water / IPA = 1/1 solution. A hydrolyzed solution adjusted to a solid content of 5 wt% (in terms of R ² Si (OH) ₃ ).

  A gas barrier film laminate having heat treatment resistance according to Example 2 was prepared in the same manner as in Example 1 except that the following D liquid was used instead of the above C liquid.

<D liquid>
Hydrochloric acid (1N) is gradually added to the γ-glycidoxypropyltrimethoxysilane and the IPA solution, and the mixture is stirred for 30 minutes for hydrolysis, followed by hydrolysis with a water / IPA = 1/1 solution to obtain a solid content of 5%. Hydrolysis solution adjusted to (weight ratio R ² Si (OH) ₃ conversion).

  A gas barrier film laminate having heat sterilization resistance according to Example 3 in the same manner as in Example 1 except that a substrate subjected to reactive ion etching on the corona-treated surface of a polyethylene terephthalate film having a thickness of 12 μm was used. Created the body.

  A gas barrier film laminate according to Example 4 for comparison was prepared in the same manner as in Example 1 except that reactive ion etching was not performed on the polyethylene terephthalate film.

  Except that the gas barrier coating layer was prepared using a solution in which the liquid A and the liquid B were mixed at a blending ratio (wt%) at 60/40 without adding the liquid C, in the same manner as in Example 1, A gas barrier film laminate according to Example 5 for comparison was prepared.

<Prototype packaging materials>
An unstretched polypropylene film having a thickness of 30 μm is laminated as a heat seal layer by dry lamination on a gas barrier film layer of the gas barrier film laminate of Examples 1 to 5 via a two-component curable urethane adhesive, and packaged. Obtained material.

<Evaluation>
Using the packaging material obtained by the above trial manufacture, a pouch having four sides as a seal portion was produced, and 200 g of water was filled as the contents. Thereafter, after retort sterilization under the following conditions 1 and 2, oxygen permeability measurement and laminate strength measurement were performed. The results are shown in Table 1.

<Retort conditions>
Condition 1 ... 121 ° C, 30 minutes Condition 2 ... 130 ° C, 60 minutes (1) Measurement of oxygen permeability Oxygen permeability after retort sterilization (unit: cm ³ / m ² / day) is 30 ° C- The measurement was performed under the condition of 70% RH.

(2) Measurement of laminate strength The laminate strength (unit: N / 15 mm) on the gas barrier coating layer side of the packaging material was measured under the conditions of a sample width of 15 mm, a peeling angle of 180 degrees, and a peeling speed of 300 mm / min.

It is explanatory drawing which shows the general | schematic cross-section structure of the gas barrier film laminated body which has the heat processing tolerance of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Base material 2 ... Deposition thin film layer 3 which consists of inorganic oxides ... Gas barrier film layer 4 ... Pre-processing surface by RIE

Claims (9)

At least one surface of a base material made of a plastic material is pretreated by reactive ion etching (RIE) using plasma, and deposition of an inorganic oxide is performed on the pretreated surface by RIE. A thin film layer and a silicon compound represented by Si (OR ¹ ) ₄ and R ² Si (OR ³ ) ₃ (R ¹ and R ³ are hydrolyzable groups, and R ² is an organic functional group) A gas barrier film having heat treatment resistance, characterized in that a decomposition product and a gas barrier film layer formed by heating and drying a thin film comprising a mixed solution containing at least a water-soluble polymer having a hydroxyl group are sequentially laminated. Laminated body. The gas barrier film laminate having heat treatment resistance according to claim 1, wherein the hydrolyzable group (R ¹ ) of Si (OR ¹ ) ₄ is C ₂ H ₅ . The heat treatment according to claim 1 or 2, wherein the organic functional group (R ² ) of R ² Si (OR ³ ) ₃ is a non-aqueous functional group such as vinyl, epoxy, methacryloxy, ureido, or isocyanate. A gas barrier film laminate having resistance. The gas barrier film laminate having a heat treatment resistance according to claim 3, wherein the organic functional group (R ² ) is a γ-glycidoxypropyl group or a β- (3,4 epoxycyclohexyl) group. Si a (OR ¹⁾ ₄ to SiO _2, when converted to R ² Si (OR ^{₃₎ 3} in _{^{R 2 Si (OH) 3,}} R 2 Si (OH) 1~ 3 of solids relative to the total solids content It is 50 weight%, The gas barrier film laminated body which has the heat processing tolerance in any one of Claims 1-4 characterized by the above-mentioned. When Si (OR ¹ ) ₄ is converted to SiO ₂ and R ² Si (OR ³ ) ₃ is converted to R ² Si (OH) ₃ , the solid content is SiO ₂ / (R ² Si (OH) in weight ratio. The gas barrier film laminate having heat treatment resistance according to any one of claims 1 to 5, wherein ₃ / water-soluble polymer) is in the range of 100/100 to 100/30.   The plastic material has at least one of polyethylene, polypropylene, polyamides, polyesters, polycarbonate, polyacrylonitrile, polystyrene, polyvinyl chloride, polyvinyl alcohol, and polyurethane as a component, or has as a copolymer component. The gas barrier film laminate having heat treatment resistance according to any one of claims 1 to 6.   8. The gas barrier film laminate having heat treatment resistance according to claim 7, wherein the polyester is polyethylene terephthalate, polyethylene naphthalate, boribylene terephthalate, boribylene naphthalate or a copolymer thereof.   The gas barrier film laminate having heat sterilization resistance according to any one of claims 1 to 8, wherein the inorganic oxide is aluminum oxide, silicon oxide, or a mixture thereof.

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