JP2009220530A - Gas-barrier film and packaging material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a gas-barrier film superior in transparency and physical strength, having a high gas-barrier property also not lower the gas-barrier property and interlayer adhesive properties in each of a substrate, a vapour deposition thin-film layer and an adhesive layer even if it is under severe situations such as a boiling sterilization and heating-pressurizing sterilization. <P>SOLUTION: The gas-barrier film is characterized by having the substrate made of a plastic film, the vapour deposition thin-film layer which consists of an inorganic oxide which is laminated to at least one side of the substrate and a gas-barrier coated layer containing a polymer having a polysilsesquioxane and hydroxyl group. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a gas barrier film used in the packaging field of foods, non-foods and pharmaceuticals, and is particularly excellent in transparency and physical strength, has high gas barrier properties, and is laminated and bonded to a plastic film as a substrate. In particular, the present invention relates to a packaging material that has a high adhesion, particularly high wet adhesion, and whose laminated portion does not easily peel off even when used for boiling sterilization or heat / pressure sterilization.

  Various functions are required for the packaging material. Among them, content protection is the most important function. Deterioration and alteration of the contents are promoted mainly by the influence of oxygen, moisture, light, heat and the like. In particular, the influence of oxygen and moisture is great. It is important to consider blocking the contents, and an excellent gas barrier film is desired. In addition, it is necessary to block not only the blocking of gas components from the outside but also the passage of flavor components and aroma components from the inside to the outside in situations where the preference is diversified and additives are regulated as in today's situation. There is. However, in general, a plastic film has a poor gas barrier property in a single layer, and a more excellent gas barrier property is imparted by laminating other layers having excellent gas barrier properties. For example, there is a gas barrier film in which a gas barrier layer containing a polyvinyl alcohol (PVA) component is laminated on a base material layer. This film is known to have a high resin crystallinity and an excellent oxygen barrier property in a dry state, but the crystallinity is lowered and the gas barrier property is remarkably lowered under high humidity conditions. Further, a gas barrier film in which a gas barrier layer made of polyvinylidene chloride resin is laminated on a base material layer has been put into practical use. However, since it contains a chlorine component, harmful dioxins may be generated during disposal. Further, although a gas barrier film in which a gas barrier layer made of an ethylene / vinyl alcohol copolymer is laminated on a base material layer has been devised, it is dependent on humidity and cannot be said to be sufficient. A gas barrier film in which a base material is coated with a coating agent mainly composed of a mixture of polyvinyl alcohol and polyacrylic acid has been devised, but has an excellent oxygen barrier property but an insufficient water vapor barrier property.

  Therefore, as a packaging material that overcomes these drawbacks, a gas barrier film in which a vapor deposition layer of an inorganic oxide such as silicon oxide, aluminum oxide, magnesium oxide or the like is formed on a polymer film by means of vacuum vapor deposition or sputtering. Has been developed. These vapor-deposited layers are known to have transparency and gas barrier properties such as oxygen and water vapor, and are suitable for packaging materials having both transparency and gas barrier properties that cannot be obtained with metal foil or the like. Yes.

Furthermore, a gas barrier film has been devised in which a gas barrier film layer is laminated on an inorganic oxide vapor-deposited thin film layer formed on a polymer film (see, for example, Patent Document 1).
Japanese Patent Laid-Open No. 7-164591

  The proposed gas barrier film did not deteriorate the gas barrier properties even after various processing such as printing, but it was used under severe conditions such as high temperature, high humidity, boiling sterilization, and heating / pressure sterilization. As a result, the gas barrier and the adhesion are disadvantageous.

  Therefore, in the present invention, it has excellent transparency and physical strength, has a high gas barrier property, and has a gas barrier property even under severe conditions such as high temperature, high humidity, boiling sterilization and heating / pressure sterilization. Another object of the present invention is to provide a gas barrier film in which the interlayer adhesion of each of a substrate, a vapor deposition thin film layer, and an adhesive layer does not deteriorate and a packaging material using the same.

  The present invention is for achieving the above object, and the invention described in claim 1 includes a base material made of a plastic film, and a vapor deposition thin film layer made of an inorganic oxide laminated on at least one surface of the base material. A gas barrier film comprising a polysilsesquioxane laminated on the vapor-deposited thin film layer and a gas barrier film layer containing a polymer having a hydroxyl group.

In the invention described in claim 2, the gas barrier coating layer is further represented by Si (OR ¹ ) ₄ or R ² Si (OR ³ ) ₃ (wherein R ^{1 to} R ³ are organic groups). The gas barrier film according to claim 1, comprising a silicon compound or a hydrolyzate thereof.

  The invention described in claim 3 is the gas barrier film according to claim 1 or 2, wherein the polymer having a hydroxyl group is polyvinyl alcohol.

  The invention described in claim 4 is the gas barrier film according to any one of claims 1 to 3, wherein the substrate is selected from the group consisting of a polyester film and a polyamide film.

  The invention described in claim 5 is the gas barrier film according to any one of claims 1 to 4, further comprising an anchor coat layer between the base material and the deposited thin film layer.

  The invention described in claim 6 is the gas barrier film according to claim 5, wherein the anchor coat layer contains an acrylic polyol, an isocyanate, and a silane coupling agent.

  The invention described in claim 7 is characterized in that the inorganic oxide of the deposited thin film layer is selected from the group consisting of aluminum oxide, silicon oxide and magnesium oxide, and mixtures thereof. The gas barrier film according to any one of the above.

  The invention described in claim 8 is a packaging material comprising the gas barrier film according to any one of claims 1 to 7.

  By having the above configuration, it has excellent transparency and physical strength characteristics, and has high gas barrier properties, and under severe conditions such as high temperature, high humidity, boiling sterilization and heating / pressure sterilization. Moreover, it can be set as the gas barrier film which does not fall gas barrier property, and the adhesiveness with a vapor deposition thin film layer or an adhesive bond layer, and a packaging material using the same.

  Furthermore, the gas barrier film of the present invention is applied not only for food use but also as a packaging film for pharmaceuticals, precision electronic parts, etc. that require higher gas barrier properties and adhesion, and provides a packaging material with a wide range of practical use. Is possible.

  Hereinafter, an embodiment of a gas barrier film of the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view illustrating a gas barrier laminate 20 according to the present invention. A gas barrier film 10 is formed by sequentially laminating an anchor coat layer 2, a vapor-deposited thin film layer 3 made of an inorganic oxide, and a gas barrier coating layer 4 using a plastic film 1 as a base material. The gas barrier laminate 20 according to the present invention has a configuration in which a heat-sealable resin layer 6 is laminated on a gas barrier coating layer 4 of a gas barrier film 10 with an adhesive layer 5 interposed therebetween.

  The plastic film 1 used in the present invention is preferably a transparent film substrate if possible in order to make use of the transparency of the deposited thin film layer. For example, polyester film such as polyethylene terephthalate (PET) or polyethylene naphthalate (PEN), polyolefin film such as polyethylene or polypropylene, polystyrene film, polyamide film, polyvinyl chloride film, polycarbonate film, polyacrylonitrile film, polyimide film or Biodegradable films such as polylactic acid films are used, and those having mechanical strength and dimensional stability are good. Particularly, a film stretched in a biaxial direction is preferable, and a polyester film or a polyamide film is particularly preferable. . Further, the plastic film 1 may be left untreated on the surface on which other layers are laminated, or subjected to surface treatment for improving adhesion, such as corona treatment, low temperature plasma treatment, or ion bombardment treatment. In addition, various known additives and stabilizers such as an antistatic agent, an ultraviolet ray preventing agent, a plasticizer, and a lubricant may be used. A thickness of about 6 to 200 μm is used depending on the application.

As the polyester film usable in the present invention, the storage elastic modulus at a temperature of −20 ° C. to + 40 ° C. is in the range of 9 × 10 ⁸ to 1 × 10 ¹⁰ Pa, and the β transition tan δ peak temperature is + 10 ° C. or less. If it is a polyester-type film which has the dynamic viscoelasticity recognized by (3), it will not restrict | limit in particular. When the storage elastic modulus is less than 9 × 10 ⁸ Pa, the flexibility of the polyester film is insufficient, and impact resistance and pinhole resistance equivalent to those of the polyamide film cannot be obtained. On the other hand, when the storage elastic modulus exceeds 1 × 10 ¹⁰ Pa, the flexibility is sufficient, but the handling property as a stretched film is inferior. Furthermore, when the peak temperature due to the β transition of the polyester film is not observed at + 10 ° C. or lower, the molecular chain cannot respond to an external load in the low temperature region, so that deformation in the low temperature region becomes difficult, and Bending pinhole resistance is insufficient. Moreover, it is preferable that it is a transparent film base material if possible in order to make use of transparency of a vapor deposition thin film layer.

  Examples of the polyester film under the above conditions include, for example, terephthalic acid, naphthalenecarboxylic acid, isophthalic acid, diphenyldicarboxylic acid, diphenylsulfone dicarboxylic acid, diphenoxyethanedicarboxylic acid, 5-sodium sulfone as a dicarboxylic acid component constituting the polyester. Aromatic dicarboxylic acids such as isophthalic acid and phthalic acid, aliphatic dicarboxylic acids such as cyclohexyne dicarboxylic acid, aliphatic dicarboxylic acids such as oxalic acid, succinic acid, adipic acid, sebacic acid, dimer acid, maleic acid and fumaric acid, and oxycarboxylic acids such as p-oxybenzoic acid. Examples of the alcohol component include aliphatic glycols such as ethylene glycol, propanediol, 1,4-butanediol, 1,6-hexanediol, and neopentyl glycol, diethylene glycol, triethylene glycol, polyethylene glycol, polypropylene glycol, 1,4- Examples thereof include polyoxyalkylene glycols such as cyclohexanedimethanol, aromatic glycols such as bisphenol A and bisphenol S, and derivatives thereof. Among these polyesters, those mainly composed of polyethylene terephthalate are preferable from the viewpoints of film forming properties such as biaxial stretching properties, humidity properties, heat resistance, chemical resistance, and low cost. Within the range where the various physical properties of polyethylene terephthalate can be maintained, other alcohol components are controlled to be incorporated into the main chain in the polymerization stage and copolymerized to form segments with low rotational hindrance (soft segments) in the molecular chain. In addition, external impact or bending force is absorbed by the soft segment in the molecular chain, and the impact resistance and flexibility are excellent. Copolyesters in which 50 mol% or more of each of the carboxylic acid component and the alcohol component of the polyester of the present invention are terephthalic acid, ethylene glycol, and derivatives thereof are preferably used.

  Regarding the stretching ratio of the polyester film, there are a sequential biaxial stretching process and a simultaneous biaxial stretching process, and the stretching ratio (vertical stretching ratio × horizontal stretching ratio) is preferably 5 to 20 times. Moreover, it is preferable that the hot-water heating shrinkage | contraction rate on 120 degreeC and 30 minute conditions at the time of forming into a film on the said conditions shall be 4% or less in MD / TD direction. When the content exceeds 4%, the shrinkage is large, and the deterioration of the gas barrier property after post-processing becomes large.

  The material of the polyamide-based film that can be used in the present invention is not particularly limited, and homopolyamide, copolyamide, or a mixture thereof can be used.

  Examples of homopolyamides include polycaprolactam (nylon 6), poly-ω-aminoheptanoic acid (nylon 7), poly-ω-aminononanoic acid (nylon 9), polyundecanamide (nylon 11), polylaurin lactam (nylon). 12), polyelylenediamine adipamide (nylon 2,6), polytetramethylene adipamide (nylon 4,6), polyhexamethylenediadipamide (nylon 6,6), polyhexamethylene sebacamide ( Nylon 6,10), polyhexamethylene decamide (nylon 6,12), polyoctamethylene adipamide (nylon 8,6), polydecamethylene adipamide (nylon 10,6), polydecamethylene sebacamide (Nylon 10, 10), polydecamethylene dodecamide (nylon 12, 12), metal Examples thereof include silyleneamine-6 nylon (MXD6).

  Examples of copolyamides include caprolactam / laurin lactam copolymer, caprolactam / hexamethylene diammonium adipate copolymer, laurin lactam / hexamethylene diammonium sebacate copolymer, hexamethylene diammonium adipate / hexamethylene diammonium. Examples thereof include a sebacate copolymer, caprolactam / hexamethylene diammonium adipate / hexamethylene diammonium sebacate copolymer, and the like. What is necessary is just to select suitably in consideration of the use environment of a gas barrier film, the kind of to-be packaged object, workability, economical efficiency, etc.

  In addition, these polyamide-based films are blended with plasticizers such as aromatic sulfonamides, p-hydroxybenzoic acid and esters to give flexibility, and low modulus elastomer components and lactams. It is also possible to do. Examples of the elastomer component include ionomer resin, modified polyolefin resin, thermoplastic polyurethane, polyether block amide, polyester block amide, polyether ester amide elastomer, modified acrylic rubber, and modified ethylene propylene rubber.

  In order to improve the adhesion between the plastic film 1 and the deposited thin film layer 3 made of an inorganic oxide, an anchor coat layer 2 is provided. The purpose of this layer is to increase the adhesion between the plastic film 1 and the vapor-deposited thin film layer 3 made of an inorganic oxide, and to prevent gas barrier properties and strength reduction.

  As a result of intensive studies, the anchor coat layer is preferably a silane coupling agent or a hydrolyzate thereof, or a composite of them with a polyol and an isocyanate compound in order to achieve the above object.

  As the silane coupling agent, a silane coupling agent containing any organic functional group can be used, for example, ethyltrimethoxysilane, vinyltrimethoxysilane, γ-chloropropylmethyldimethoxysilane, γ-chloropropyltrimethoxy. A silane coupling agent such as silane, glycidoxypropyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropylmethyldimethoxysilane, or one or more of hydrolysates thereof can be used. .

  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 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 interacts in a composite composed of a polyol and an isocyanate 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 generated by hydrolysis of the alkoxy group at the other end is formed on the metal in the inorganic oxide or on the surface of the inorganic oxide. High adhesiveness with inorganic oxides can be expressed by strong interaction with a highly active 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.

  The polyol has two or more hydroxyl groups at the polymer terminal and is reacted with an isocyanate group in an isocyanate compound added later. Among them, 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 and other monomers is particularly preferable. Among them, 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 reactivity with the isocyanate compound, the hydroxyl value is preferably between 5 and 300 (KOHmg / g).

  The blending ratio of the polyol and the silane coupling agent is preferably in the range of 1/1 to 1000/1, more preferably in the range of 2/1 to 100/1, in terms of weight ratio. Solvent and dilution solvents are not particularly limited as long as they 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, and toluene Aromatic hydrocarbons such as xylene can be used alone or arbitrarily blended. 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.

Even if a reaction catalyst is added to promote the reaction at the time of blending the silane coupling agent and the polyol, it does not matter. 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, etc. in terms of reactivity and polymerization stability. Is preferred. Since the catalytic effect is not obtained if the addition amount is too small or too large, it is preferably in the range of 1/10 to 1 / 10,000 in terms of molar ratio with respect to the trifunctional organosilane. More preferably, it is in the range of 1/2000.

  The isocyanate compound is added in order to increase the adhesion between the base material and the inorganic oxide layer by a urethane bond formed by reacting with a polyol, and mainly functions 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 hexamethylene diisocyanate (HMDI), These polymers, derivatives, etc. are mentioned, These can be used 1 type or 2 or more types.

  The blending ratio of the polyol and the isocyanate compound is not particularly limited, but if the isocyanate compound is too small, 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 isocyanate compound, the NCO group derived from the isocyanate compound is preferably 50 times or less than the OH group derived from the polyol, and particularly preferably, the NCO group and the OH group are blended in an equal amount. Is the case. As a mixing method, a known method can be used and is not particularly limited.

Furthermore, in order to improve the liquid stability during the preparation of the above mixture, a metal alkoxide or a hydrolyzate thereof may be added. This metal alkoxide is a general formula M (OR) _n (M: metal element, R: CH) such as tetraethoxysilane (Si (OC ₂ H ₅ ) ₄ ), tripropoxyaluminum (Al (OC ₃ H ₇ ) ₃ ), etc. _3, is a _C 2 _{H 5} general formula _C n _H expressed as or a hydrolyzate thereof with an alkyl group) represented by _{2n + 1,} such as. Of these, tetraethoxysilane, tripropoxyaluminum, or a mixture of both is preferable because it is relatively stable in an aqueous solvent. The metal alkoxide hydrolyzate may be hydrolyzed together with the silane coupling agent or may be added after an acid or the like is added alone.

  The composite coating layer may be directly or previously hydrolyzed with such a silane coupling agent or hydrolyzed 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) In addition, an isocyanate compound is added to prepare a composite liquid, and the base material 1 is coated.

  Various additives such as tertiary amines, imidazole derivatives, carboxylic acid metal chlorides, quaternary ammonium salts, quaternary phosphonium salts, and other accelerators, phenols, sulfurs, phosphites It is also possible to add an antioxidant, a leveling agent, a flow regulator, a catalyst, a crosslinking accelerator, a filler and the like.

  The thickness of the anchor coat layer 2 is not particularly limited as long as a uniform coating film can be formed, but it is generally desirable to be in the range of 0.001 to 2 μm. When the thickness is less than 0.01 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 by an external factor, which is not preferable. Particularly preferred is a range of 0.03 to 0.5 μm.

  As a method for forming the anchor coat 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 a roll coating, a knife edge coating, or a gravure coating may be used. it can. About drying conditions, generally used conditions may be used. In order to promote the reaction, it may be left in a high temperature aging chamber for several days.

  Next, the vapor-deposited thin film layer 3 made of inorganic oxide is made of silicon oxide, aluminum oxide, tin oxide, magnesium oxide, or a mixture thereof, and has transparency and gas barrier properties such as oxygen and water vapor. That's fine. Among these, aluminum oxide and silicon oxide are particularly preferable. However, the vapor-deposited thin film layer 3 of the present invention is not limited to the inorganic oxide described above, and any material that meets the above conditions can be used.

  The optimum thickness of the vapor-deposited thin film layer 3 varies depending on the type and configuration of the inorganic compound to be used, but is generally preferably 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. On the other hand, when the film thickness exceeds 300 nm, flexibility cannot be maintained in the thin film, and the thin film may be cracked due to external factors such as bending and pulling after film formation. Preferably, it exists in the range of 10-150 nm.

  There are various methods for forming the deposited thin film layer 3 on the anchor coat layer 2, and it can be formed by a normal vacuum deposition method. However, other thin film forming methods such as sputtering, ion plating, and plasma gas phase A growth method (CVD) or the like can also be used. However, considering productivity, the vacuum deposition method is the best at present. As the heating means of the vacuum deposition apparatus by the vacuum deposition method, the electron beam heating method, the resistance heating method, and the induction heating method are preferable. In order to improve the adhesion between the thin film and the substrate and the denseness of the thin film, a plasma assist method or an ion It is also possible to use a beam assist method. In addition, in order to increase the transparency of the deposited film, it is possible to carry out reactive deposition such as blowing oxygen gas during deposition.

  The gas barrier coating layer 4 is provided on the vapor-deposited thin film layer 3 in order to provide a gas barrier property that is as high as an aluminum foil depending on the required quality.

The gas barrier coating layer 4 in the present invention contains polysilsesquioxane and a polymer having a hydroxyl group. The gas barrier coating layer 4 further contains a silicon compound represented by Si (OR ¹ ) ₄ or R ² Si (OR ³ ) ₃ (where R ^{1 to} R ³ are organic groups) or a hydrolyzate thereof. It may be.

The gas barrier coating layer 4 is obtained by dissolving polysilsesquioxane and a polymer having a hydroxyl group in an aqueous (water or water / alcohol mixed) solvent, and if necessary, Si (OR ¹ ) ₄ or R ² Si (OR ³ ) ₃ (wherein R ^{1 to} R ³ are organic groups) An aqueous solution or a water / alcohol mixed solution in which a hydrolyzate obtained by performing a treatment such as hydrolyzing the silicon compound directly or in advance is mixed. It is formed by coating the vapor-deposited thin film layer 3 with a coating liquid as a main agent and drying by heating.

Each component contained in the gas barrier coating layer 4 will be described in more detail.
Examples of the polymer having a hydroxyl group include polyvinyl alcohol, starch, methyl cellulose, carboxymethyl cellulose, and sodium alginate. In particular, the gas barrier coating layer 4 formed using a coating liquid containing polyvinyl alcohol (hereinafter referred to as PVA) has the best gas barrier properties. PVA is generally obtained by saponifying polyvinyl acetate, and includes a range from a so-called partially saponified PVA in which several tens percent of acetic acid groups remain to fully saponified PVA in which only several percent of acetic acid groups remain, but is not particularly limited. .

The polysilsesquioxane means a silicon oxide oligomer or ladder-type (ladder-type) silicon oxide polymer having a cage shape. Silsesoxane is a compound represented by [RSiO _3/2 ]. Silsesquioxane is usually a polysynthesized by hydrolysis-polycondensation of RSiX ₃ (R = hydrogen atom, alkyl group, alkenyl group, aryl group, araalkyl group, etc., X = halogen, alkoxy group, etc.) type compound. Siloxane, which is typically an amorphous structure, a ladder structure, a cage structure, or a partially cleaved structure (a structure in which one silicon atom is missing from the cage structure or a cage structure). A structure in which the silicon-oxygen bond in the part is broken) is known.

A silicon compound represented by Si (OR ¹ ) ₄ or R ² Si (OR ³ ) ₃ (where R ^{1 to} R ³ are organic groups) is hydrolyzed and condensed to obtain a metal oxide polymer. If it can do, it will not specifically limit. Examples of the silicon compound represented by Si (OR ¹ ) ₄ or R ² Si (OR ³ ) ₃ (where R ^{1 to} R ³ are organic groups) include tetraalkoxysilanes such as tetramethoxysilane and tetraethoxysilane. Arylarylalkoxysilanes such as phenyltrimethoxysilane and phenyltriethoxysilane; alkyltrialkoxysilanes such as methyltrimethoxysilane, ethyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, methyltriethoxysilane, and ethyltriethoxysilane Arylaryl dialkoxysilanes such as phenylmethyldimethoxysilane, phenylethyldimethoxysilane, phenylmethyldiethoxysilane, phenylethyldiethoxysilane; dimethyldimethoxysilane, diethyldimethoxy Dialkyl dialkoxysilanes such as lan, dimethyldiethoxysilane, diethyldiethoxysilane; diphenylmethylmethoxysilane, phenyldimethylmethoxysilane, diphenylethylmethoxysilane, phenyldiethylmethoxysilane, diphenylmethylethoxysilane, phenyldimethylethoxysilane, diphenylethyl Diarylalkylalkoxysilanes or aryldialkylalkoxysilanes such as ethoxysilane and phenyldiethylethoxysilane; triarylalkoxysilanes such as triphenylmethoxysilane and triphenylethoxysilane; trimethylmethoxysilane, triethylmethoxysilane, trimethylethoxysilane, triethylethoxysilane And the like, and the like. Each of the above components can be added to the gas barrier coating layer alone or in combination.

  Furthermore, known additives such as an isocyanate compound, a silane coupling agent, a dispersant, a stabilizer, a viscosity modifier, and a colorant can be added within a range that does not impair the gas barrier property of the gas barrier coating layer.

  The isocyanate compound added to the gas barrier coating layer has two or more isocyanate groups (NCO groups) in the molecule. For example, tolylene diisocyanate (hereinafter referred to as TDI), triphenylmethane triisocyanate (hereinafter referred to as TTI). ), Tetramethylxylene diisocyanate (hereinafter referred to as TMXDI), and polymers and derivatives thereof.

  Conventionally known means such as a dipping method, a roll coating method, a screen printing method, and a spray method can be used as a method for applying the coating liquid for the gas barrier coating layer. The thickness of the coating layer varies depending on the type of coating liquid and the processing conditions, and it is sufficient that the thickness after drying is 0.01 μm or more. However, if the thickness is 50 μm or more, cracks are likely to occur in the film. A range of 50 μm is preferred.

  Further, other layers can be laminated on the vapor-deposited thin film layer 3 and the gas barrier coating layer 4. For example, a printing layer, an intermediate layer, a heat seal layer, and the like. The printed layer is formed for practical use as a packaging bag or the like. The print layer is made of urethane, acrylic, nitrocellulose, rubber, vinyl chloride, and other conventionally used ink binder resins with various pigments, extenders, plasticizers, desiccants, stabilizers, etc. It is composed of ink to which an agent or the like is added, and characters, pictures, etc. are formed. As a method for forming the printing layer, for example, a known printing method such as an offset printing method, a gravure printing method, or a silk screen printing method, or a known coating method such as roll coating, knife edge coating, or gravure coating can be used. The thickness of the printing layer may be 0.1 to 2.0 μm.

  The gas barrier laminate 20 can be obtained by laminating the heat-sealable resin layer 6 via the adhesive layer 5 on the surface of the gas barrier film layer 4 of the gas barrier film 10 having the above-described configuration.

As the adhesive layer 5 in the present invention, a general-purpose laminating adhesive can be used. For example, poly (ester) urethane, polyester, polyamide, epoxy, poly (meth) acrylic, polyethyleneimine, ethylene- (meth) acrylic acid, polyvinyl acetate, (modified) polyolefin, polybutadiene (No) solvent type, water-based type, and heat-dissolving type adhesives mainly composed of a wax type, wax type, casein type, and the like can be used. The adhesive layer 5 is applied by, for example, a direct gravure coating method, a reverse gravure coating method, a kiss coating method, a die coating method, a roll coating method, a dip coating method, a knife coating method, a spray coating method, a fountain coating method, or other methods. The coating thickness is preferably about 0.1 to 8 g / m ² (dry state).

  The heat-sealable resin layer 6 used in the present invention is provided as a seal layer when forming a bag-like package or the like, and is particularly limited as long as it can be melted by heat and fused to each other. It is not something. For example, high density polyethylene, medium density polyethylene, low density polyethylene, linear low density polyethylene, other polyethylene resin, polypropylene, ethylene-propylene copolymer resin, polyester resin, polyamide resin, ethylene-vinyl acetate copolymer And saponified products thereof, polycarbonate resins, polyacrylonitrile resins, nitrocellulose, ethylene- (meth) acrylic acid copolymers, ethylene- (meth) acrylic ester copolymers, and their metal cross-linked products, polylactic acid resins Any other known biodegradable resin and other known resins can be used. The thickness may be determined according to the purpose, and is generally in the range of 10 to 200 μm.

  As a method of laminating the heat-sealable resin layer 6 on the gas barrier film 10, a known laminating method such as a dry laminating method, a non-solvent laminating method, or an extrusion laminating method can be used. Further, in the gas barrier laminate 20, a heat-sealable resin layer 6 is formed after laminating a printing layer or other base film on the gas barrier coating layer 4 of the gas barrier transparent film 10 according to the use / requirement. It is also possible to provide a desired packaging material.

  In the following, embodiments of the present invention will be described in more detail. However, the present invention is not limited to this.

<Preparation of coating solution for anchor coat layer>
In a diluting solvent (ethyl acetate), acrylic polyol and tolylene diisocyanate are mixed so that the NCO groups are equivalent to the OH groups, so that the total solid content is 5 w%. Next, β- (3,4-epoxycyclohexyl) trimethoxysilane is added to and mixed with 5% by weight based on the total solid content to prepare a coating solution for the anchor coat layer.

<Preparation of coating solution for gas barrier coating layer>
(A) 22.4 g of hydrochloric acid (0.02N) was added to 6.84 g of polysilsesquioxane (R = C ₂ H ₅ , weight average molecular weight 1700) in a diluting solvent, and the mixture was hydrolyzed by stirring for 30 minutes. Hydrolysis solution of 5% (weight ratio SiO ₂ conversion).

(B) In dilute solvent, 22.4 g of hydrochloric acid (0.02N) was added to 9.14 g of polysilsesquioxane (R = C ₂ H ₅ , weight average molecular weight 5600), and the mixture was hydrolyzed by stirring for 30 minutes. Hydrolysis solution of 5% (weight ratio SiO ₂ conversion).

(C) In a dilute solvent, 72.1 g of hydrochloric acid (0.1N) was added to 17.9 g of tetraethoxysilane (Si (OC ₂ H ₅ ) ₄ ; hereinafter referred to as TEOS), and the mixture was hydrolyzed by stirring for 30 minutes. Hydrolysis solution of 5% (weight ratio SiO ₂ conversion).

  (D) 5% (weight ratio) of polyvinyl alcohol, water / methanol = 95/5 (weight ratio) aqueous solution.

(E) Hydrochloric acid (1N) was gradually added to γ-glycidoxypropyltrimethoxysilane in a diluting solvent, and the mixture was stirred for 30 minutes for hydrolysis, and then solid content 5% (weight ratio R ₂ Si (OH) ₃ Hydrolysis solution adjusted to (conversion).

<Combination ratio of gas barrier coating solution>
A: SiO ₂ solid content (converted value) of polysilsesquioxane (R = C ₂ H ₅ , weight average molecular weight 1700)
B: SiO ₂ solid content (converted value) of polysilsesquioxane (R = C ₂ H ₅ , weight average molecular weight 5600)
C: SiO ₂ solid content of TEOS (converted value)
D: PVA solid content E; R ² Si (OH) ₃ conversion of γ-glycidoxypropyltrimethoxysilane All the mixing ratios are solid content weight ratios.

Gas barrier coating liquid Ia A / D = 70/30
Gas barrier coating liquid IIa B / D = 70/30
Gas barrier coating liquid IIIa A / C / D = 35/35/30
Gas barrier coating liquid IVa A / C / D = 60/10/30
Gas barrier coating liquid Va B / C / D = 35/35/30
Gas barrier coating liquid VIa B / C / D = 60/10/30
Gas barrier coating liquid VIIa C / D = 70/30
Gas barrier coating liquid VIIIa C / D = 50/50
Gas barrier film coating liquid Ib A / D / E = 70/20/10
Gas barrier film coating solution IIb B / D / E = 70/20/10
Gas barrier coating liquid IIIb A / C / D / E = 35/35/20/10
Gas barrier coating liquid IVb A / C / D / E = 60/10/20/10
Gas barrier coating liquid Vb B / C / D / E = 35/35/20/10
Gas barrier coating liquid VIb B / C / D / E = 60/10/20/10
Gas barrier film coating solution VIIb C / D / E = 70/20/10
Gas barrier coating liquid VIIIb C / D / E = 45/45/10
<Example 1>
As the substrate 1, a polyester resin film having a thickness of 15 [mu] m on which one side is corona-treated is used. Using a gravure coater, the coating solution for the anchor coat layer is applied to the corona-treated surface and dried to have a thickness of 0.1 [mu] m. An anchor coat layer 2 made of a dry film was laminated. Next, a deposited thin film layer 3 made of aluminum oxide having a thickness of 15 nm was deposited by a vacuum deposition apparatus. Next, the gas barrier film layer 4 comprising a dry film having a thickness of 0.2 μm was laminated on the vapor-deposited thin film layer 3 by applying the coating liquid Ia of the gas barrier film layer and drying it to obtain a gas barrier film.

Furthermore, on the gas barrier film layer 4 of the gas barrier film, an adhesive layer is formed at a coating amount of 3.5 g / m ² using a polyurethane adhesive (A525, manufactured by Mitsui Chemicals Polyurethane) by a dry lamination method. A polyamide film having a thickness of 15 μm was laminated thereon, and an unstretched polypropylene film having a thickness of 70 μm was further laminated thereon, followed by curing at 50 ° C. for 4 days to obtain a gas barrier laminate of the present invention.

<Example 2>
A gas barrier laminate of the present invention was obtained in the same manner as in Example 1 except that the gas barrier film layer 4 was formed using the coating liquid IIa for the gas barrier film layer.

<Example 3>
A gas barrier laminate of the present invention was obtained in the same manner as in Example 1 except that the gas barrier film layer 4 was formed using the coating liquid IIIa for the gas barrier film layer.

<Example 4>
A gas barrier laminate of the present invention was obtained in the same manner as in Example 1 except that the gas barrier film layer 4 was formed using the coating liquid IVa for the gas barrier film layer.

<Example 5>
A gas barrier laminate of the present invention was obtained in the same manner as in Example 1 except that the gas barrier film layer 4 was formed using the coating liquid Va for the gas barrier film layer.

<Example 6>
A gas barrier laminate of the present invention was obtained in the same manner as in Example 1 except that the gas barrier film layer 4 was formed using the coating liquid VIa of the gas barrier film layer.

<Comparative Example 1>
A gas barrier laminate of the present invention was obtained in the same manner as in Example 1 except that the gas barrier film layer 4 was formed using the coating liquid VIIa of the gas barrier film layer.

<Comparative Example 2>
A gas barrier laminate of the present invention was obtained in the same manner as in Example 1 except that the gas barrier coating layer 4 was formed using the coating liquid VIIIa of the gas barrier coating layer.

<Example 7>
A gas barrier laminate of the present invention was obtained in the same manner as in Example 1 except that the gas barrier film layer 4 was formed using the coating liquid Ib for the gas barrier film layer.

<Example 8>
A gas barrier laminate of the present invention was obtained in the same manner as in Example 1 except that the gas barrier film layer 4 was formed using the coating liquid IIb of the gas barrier film layer.

<Example 9>
A gas barrier laminate of the present invention was obtained in the same manner as in Example 1 except that the gas barrier film layer 4 was formed using the coating liquid IIIb for the gas barrier film layer.

<Example 10>
A gas barrier laminate of the present invention was obtained in the same manner as in Example 1 except that the gas barrier film layer 4 was formed using the coating liquid IVb for the gas barrier film layer.

<Example 11>
A gas barrier laminate of the present invention was obtained in the same manner as in Example 1 except that the gas barrier film layer 4 was formed using the gas barrier film layer coating liquid Vb.

<Example 12>
A gas barrier laminate of the present invention was obtained in the same manner as in Example 1 except that the gas barrier film layer 4 was formed using the gas barrier film layer coating solution VIb.

<Comparative Example 3>
A gas barrier laminate of the present invention was obtained in the same manner as in Example 1 except that the gas barrier film layer 4 was formed using the coating liquid VIIb of the gas barrier film layer.

<Comparative example 4>
A gas barrier laminate of the present invention was obtained in the same manner as in Example 1 except that the gas barrier film layer 4 was formed using the coating liquid VIIIb of the gas barrier film layer.

  For the gas barrier laminates obtained in Examples 1 to 12 and Comparative Examples 1 to 4, measurement of oxygen permeability and water vapor permeability before and after retorting at 121 ° C. for 30 minutes, similarly before and after retorting at 121 ° C. for 30 minutes The laminate strength was measured. The evaluation results are shown in Table 1.

<Measurement of oxygen permeability>
For the gas barrier laminates obtained in Examples 1 to 12 and Comparative Examples 1 to 4, before and after the retorting treatment at 121 ° C. for 30 minutes, according to JIS K-7129B method, OXTRAN 2/20 manufactured by Modern Control Co. Thus, the oxygen permeability was measured under the conditions of 30 ° C. and 70% RH environment.

<Measurement of water vapor transmission rate>
For the gas barrier laminates obtained in Examples 1 to 12 and Comparative Examples 1 to 4, before and after the retorting treatment at 121 ° C. for 30 minutes, according to JIS K-7129B method, OXTRAN 3/31 manufactured by Modern Control Co., Ltd. Thus, the water vapor permeability was measured under the conditions of 40 ° C. and 90% RH environment.

<Measurement of laminate strength>
The adhesion strength between the gas barrier coating layer and the polyamide film of the gas barrier laminates obtained in Examples 1 to 12 and Comparative Examples 1 to 4 was measured according to JIS Z-1707 before and after retorting at 121 ° C. for 30 minutes. Measured according to The measurement conditions were a test width of 15 mm and a peeling speed of 300 mm / min.

  From Table 1, the gas barrier laminates of Examples 1 to 12 according to the present invention were excellent in laminate strength and oxygen and water vapor permeability. Although the laminates of Comparative Examples 1 to 4 can be said to be within the practical range for general applications, the laminates of Examples 1 to 12 are used for more demanding qualities such as high-temperature and high-pressure sterilization treatments and medical and pharmaceutical uses. Is better.

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

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Plastic film, 2 ... Anchor coat layer, 3 ... Deposition thin film layer, 4 ... Gas barrier film layer, 5 ... Adhesive layer, 6 ... Heat seal resin layer, 10 ... Gas barrier film, 20 ... Gas barrier laminated body.

Claims (8)

A substrate made of plastic film;
A vapor-deposited thin film layer made of an inorganic oxide laminated on at least one side of the substrate;
A gas barrier film comprising a polysilsesquioxane and a gas barrier coating layer containing a polymer having a hydroxyl group laminated on the vapor-deposited thin film layer. The gas barrier coating layer further contains a silicon compound represented by Si (OR ¹ ) ₄ or R ² Si (OR ³ ) ₃ (where R ^{1 to} R ³ are organic groups) or a hydrolyzate thereof. The gas barrier film according to claim 1.   The gas barrier film according to claim 1 or 2, wherein the polymer having a hydroxyl group is polyvinyl alcohol.   The gas barrier film according to any one of claims 1 to 3, wherein the substrate is selected from the group consisting of a polyester film and a polyamide film.   The gas barrier film according to any one of claims 1 to 4, further comprising an anchor coat layer between the substrate and the deposited thin film layer.   The gas barrier film according to claim 5, wherein the anchor coat layer contains an acrylic polyol, an isocyanate, and a silane coupling agent.   The gas barrier film according to any one of claims 1 to 6, wherein the inorganic oxide of the deposited thin film layer is selected from the group consisting of aluminum oxide, silicon oxide, magnesium oxide, and a mixture thereof.   A packaging material comprising the gas barrier film according to claim 1.

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