JP3736130B2 - Strong adhesion gas barrier transparent laminate and packaging body using the same - Google Patents

Description

【００６９】
表１から、実施例１〜４の本発明の強密着ガスバリア透明積層体およびそれを用いた包装体（パウチ）は内容物を直接透視することが可能なだけの透明性を有し、内容物に対して影響を与える気体等を遮断する高いガスバリア性や高いラミネート強度を有し、かつレトルト後もガスバリア性の劣化がなく、高いラミネート強度を維持し、デラミ等の発生がない優れた耐レトルト性を有していることが判る。
それに対して比較例１〜２の透明積層体およびそれを用いた包装体（パウチ）は内容物を直接透視可能な透明性を有し、レトルト前は内容物に対して影響を与える気体等を遮断するガスバリア性や高いラミネート強度を有するが、レトルト後はガスバリア性が劣化し、ラミネート強度が低下し、デラミ等が発生し、耐レトルト性が悪いことが判る。
【００７０】
【発明の効果】
本発明の強密着ガスバリア透明積層体およびそれを用いた包装体は、透明プラスチック基材上にボイル殺菌やレトルト殺菌後も寸法安定性や密着性に優れた透明プライマー層を設けた後、ガスバリア性に優れた無機酸化物からなる蒸着薄膜層を積層した構成になっているので、内容物を直接透視することが可能な透明性を有し、且つ、アルミ箔並の高度なガスバリア性を有する上、ボイル殺菌やレトルト殺菌等の後もデラミの発生やガスバリア性の劣化がなく、汎用性のある食品や非食品及び医薬品等の包装材料として、包装分野において巾広く使用可能である。
【図面の簡単な説明】
【図１】 本発明の強密着ガスバリア透明積層体の一実施形態の部分断面図である。
【符号の説明】
１ 透明プラスチック材料からなる基材
２ 透明プライマー層
３ 無機酸化物からなる蒸着薄膜層
４ ガスバリア性被膜層[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a strong adhesion gas barrier transparent laminate and a packaging body using the same, and more specifically, a strongly adhesion gas barrier transparent laminate for packaging used in the packaging field of foods, non-food products, pharmaceuticals, and the like. The present invention relates to the package used, and particularly relates to the packaging field that requires boil sterilization, retort sterilization, autoclave sterilization, and the like.
[0002]
[Prior art]
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 gases (gases). Therefore, conventionally, a packaging material using a metal foil made of a metal such as aluminum, which is less affected by temperature and humidity, as a gas barrier layer has been generally used.
[0003]
However, packaging materials using metal foil made of metal such as aluminum are excellent in gas barrier properties, but the contents cannot be confirmed through the packaging material. There are problems such as having to use the metal detector at the time of inspection.
[0004]
Therefore, as a packaging material that overcomes these drawbacks, for example, inorganic oxides such as silicon oxide, aluminum oxide, and magnesium oxide described in US Pat. No. 3,442,686, Japanese Patent Publication No. 63-28017, etc. A film in which a deposited film is formed on a polymer film by a forming means such as a vacuum deposition method or a sputtering method 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 both transparency and gas barrier properties that cannot be obtained with metal foil or the like. Yes.
[0005]
[Problems to be solved by the invention]
However, even if it is a film suitable for the packaging material described above, it is rarely used as a vapor deposition film alone as a packaging container or packaging material, and characters, designs, etc. are printed on the surface of the vapor deposition film as post-processing after vapor deposition. Or the packaging body is completed through various processes, such as bonding with a film etc. and shape processing to the packaging bodies, such as a container. In particular, packaging materials used for boil sterilization, retort sterilization, autoclave sterilization, and the like are sterilized through various processes, and therefore, care must be taken when designing packaging materials.
[0006]
Therefore, after making a bag with the sealant film bonded using the above-mentioned vapor-deposited film, etc., filling the contents and trying boil sterilization or retort sterilization resulted in delamination in part of the seal part after sterilization and poor appearance And the gas barrier property is lowered from the portion, and the contents are deteriorated.
[0007]
That is, as a condition to be used as a packaging material in such a case, transparency sufficient to directly see through the contents, high gas barrier properties that block gas etc. that affect the contents, and boil sterilization It is required to have boil resistance, retort resistance, and autoclave resistance, such as no gas barrier deterioration and no delamination after retort sterilization and autoclave sterilization. Is not found.
[0008]
The first object of the present invention is to have transparency capable of directly seeing through the contents, and has an advanced gas barrier property similar to that of an aluminum foil, and generation of delamination after boil sterilization or retort sterilization. The gas barrier property is not deteriorated, and a strong adhesion gas barrier transparent laminate that can be widely used as a versatile packaging material for foods, non-foods, and pharmaceuticals is provided. The second object of the present invention is to It is a package manufactured using this strong adhesion gas barrier transparent laminate, which is excellent in transparency and has high gas barrier properties, and there is no deterioration of physical properties after boil sterilization or retort sterilization, and there is no occurrence of demira etc. It is to provide a highly practical package having high boil resistance, retort resistance, and autoclave resistance.
[0009]
[Means for Solving the Problems]
The present invention is intended to achieve the above object, and the invention described in claim 1 is characterized in that a general formula R′Si (OR) is formed on at least one surface of a substrate made of a transparent plastic material. _Three (R ': an alkyl group, a vinyl group, a glycidoxypropyl group, R: an alkyl group, etc.) represented by a trifunctional organosilane or a hydrolyzate of the organosilane, and a composite of an acrylic polyol and an isocyanate compound. A strong adhesion gas barrier transparent laminate in which a transparent primer layer and a deposited thin film layer made of an inorganic oxide having a thickness of 5 to 300 nm are sequentially laminated.
[0010]
The invention of claim 2 is characterized in that, in the strong adhesion gas barrier transparent laminate of claim 1, R ′ constituting the trifunctional organosilane contains an epoxy group.
[0011]
The invention of claim 3 is the strong adhesion gas barrier transparent laminate according to claim 1 or 2, wherein a reaction catalyst is added to the composite.
[0012]
The invention according to claim 4 is the strong adhesion gas barrier transparent laminate according to claim 3, wherein the reaction catalyst is a tin compound.
[0013]
The invention according to claim 5 is the strong adhesion gas barrier transparent laminate according to claim 4, wherein the tin compound is a tin compound selected from tin chloride, tin oxychloride and tin alkoxide.
[0014]
The invention according to claim 6 is the strong adhesion gas barrier transparent laminate according to any one of claims 1 to 5, wherein the composite further includes a general formula M (OR). _n (M: metal element, R: CH _Three , C ₂ H _Five Or a hydrolyzate of the metal alkoxide represented by (n: oxidation number of metal element).
[0015]
The invention according to claim 7 is the strong adhesion gas barrier transparent laminate according to any one of claims 1 to 6, wherein the metal in the metal alkoxide or the hydrolyzate of the metal alkoxide is Si, Al, Ti, Zr. Alternatively, it is a mixture thereof.
[0016]
The invention according to claim 8 is the strong adhesion gas barrier transparent laminate according to any one of claims 1 to 7, wherein the thickness of the transparent primer layer is in the range of 0.01 to 2 μm. To do.
[0017]
The invention according to claim 9 is the strong adhesion gas barrier transparent laminate according to any one of claims 1 to 8, wherein the inorganic oxide is aluminum oxide, silicon oxide, magnesium oxide or a mixture thereof. It is a feature.
[0018]
A tenth aspect of the present invention is the strong adhesion gas barrier transparent laminate according to any one of the first to ninth aspects, further comprising a gas barrier coating layer laminated on the strong adhesion gas barrier transparent laminate. The gas barrier coating layer is mainly composed of an aqueous solution or a water / alcohol mixed solution containing at least one of a water-soluble polymer, (a) one or more metal alkoxides and hydrolysates thereof, or (b) tin chloride. It is a layer formed by applying a coating agent to be heated and drying by heating.
[0019]
An eleventh aspect of the invention is characterized in that in the strong adhesion gas barrier transparent laminate according to the tenth aspect, the metal alkoxide is tetraethoxysilane, triisopropoxyaluminum, or a mixture thereof.
[0020]
A twelfth aspect of the present invention is the strong adhesion gas barrier transparent laminate according to the tenth or eleventh aspect, wherein the water-soluble polymer is polyvinyl alcohol.
[0021]
A thirteenth aspect of the present invention is a package manufactured using the strong adhesion gas barrier transparent laminate according to any one of the first to twelfth aspects.
[0022]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in more detail with reference to the drawings. FIG. 1 is a cross-sectional view for explaining one embodiment of a strong adhesion gas barrier transparent laminate of the present invention.
[0023]
First, the strong adhesion gas barrier transparent laminate of the present invention shown in FIG. 1 will be described. The substrate 1 in FIG. 1 is a film made of a transparent plastic material, on which a transparent primer layer 2 made of a composite of trifunctional organosilane, acrylic polyol, isocyanate compound and the like, a vapor-deposited thin film layer 3 made of an inorganic oxide, The gas barrier coating layer 4 is sequentially laminated. In this case, the gas barrier coating layer 4 may not be provided depending on the required quality.
[0024]
The substrate 1 described above is a transparent plastic material, and a transparent film is preferable in order to make use of the transparency of the deposited thin film layer. For example, polyethylene terephthalate (PET), polyester film such as polyethylene naphthalate, polyolefin film such as polyethylene and polypropylene, polystyrene film, polyamide film, polyvinyl chloride film, polycarbonate film, polyacrylonitrile film, polyimide film, etc. are used. Either stretched or unstretched, and those having mechanical strength and dimensional stability are preferred. These are processed into a film and used. In particular, polyethylene terephthalate arbitrarily stretched in the biaxial direction is preferably used. In addition, various known additives and stabilizers such as antistatic agents, ultraviolet inhibitors, plasticizers, lubricants, and the like may be used on the surface of the substrate 1 to improve the adhesion to the thin film. In addition, corona treatment, low temperature plasma treatment, ion bombardment treatment may be performed as pretreatment, and chemical treatment, solvent treatment, and the like may be performed.
[0025]
The thickness of the substrate 1 is not particularly limited, but is suitable as a packaging material, may be laminated with other layers, a transparent primer layer 2 and a vapor-deposited thin film layer 3 made of an inorganic oxide, and gas barrier properties. Considering the workability when forming the coating layer 4, it is practically in the range of 3 to 200 μm and preferably 6 to 30 μm depending on the application.
[0026]
In consideration of mass productivity, it is desirable to use a long film so that each layer can be formed continuously.
[0027]
The transparent primer layer 2 of the present invention is provided on a base material 1 made of a transparent plastic material, enhances the adhesion between the base material 1 and a vapor-deposited thin film layer 3 made of an inorganic oxide, and boil sterilization or retort sterilization, The purpose is to prevent the occurrence of delamination after autoclave sterilization.
[0028]
As a result of intensive studies, the present inventors have been able to use a trifunctional organosilane or a hydrolyzate thereof, an acrylic polyol, an isocyanate compound, etc. as a primer resin in order to achieve the above object in the present invention. I found it to be a thing.
[0029]
Furthermore, the composite which comprises the transparent primer layer 2 is demonstrated in detail.
The trifunctional organosilane is represented by the general formula R′Si (OR) such as ethyltrimethoxysilane, vinyltrimethoxysilane, glycidoxypropyltrimethoxysilane, etc. _Three (R ′ is an alkyl group, vinyl group, glycidoxypropyl group, etc., R is an alkyl group, etc.) or a hydrolyzate thereof. Of these, glycidoxytrimethoxysilane, epoxycyclohexylethyltrimethoxysilane, and the like in which an epoxy group is contained in R ′ are particularly preferable.
A method for obtaining a hydrolyzate can be obtained by a known method such as a method of performing hydrolysis by directly adding an acid, an alkali or the like to a trifunctional organosilane.
[0030]
An acrylic polyol is a polymer compound obtained by polymerizing an acrylic acid derivative monomer, or a hydroxyl compound at the end of a polymer compound obtained by copolymerizing an acrylic acid derivative monomer and other monomers. It is to be reacted with an isocyanate group of an isocyanate compound added later. Among these, those obtained by polymerizing acrylic acid derivative monomers such as ethyl methacrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, and hydroxybutyl 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).
[0031]
The mixing ratio of the acrylic polyol and the trifunctional organosilane is preferably in the range of 1/1 to 100/1 by weight, more preferably in the range of 2/1 to 50/1.
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, A mixture of aromatic hydrocarbons such as toluene and xylene alone and arbitrarily can be used. However, since an aqueous solution of hydrochloric acid or the like may be used to hydrolyze trifunctional organosilane or the like, it is more 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.
[0032]
In addition, a reaction catalyst may be added to accelerate the reaction when the trifunctional organosilane and acrylic polyol are blended. As the catalyst to be added, tin chloride (SnCl) is used from the viewpoint of reactivity and polymerization stability. ₂ , SnCl _Four ), Tin oxychloride (SnOHCl, Sn (OH) ₂ Cl ₂ ) And tin compounds such as tin alkoxides are preferred. These catalysts may be added directly at the time of blending, or may be added after being dissolved in a solvent such as methanol. If the addition amount is too small or too large, the catalytic effect cannot be obtained, so the molar ratio with respect to the trifunctional organosilane is preferably in the range of 1/10 to 1/10000, and more preferably 1/100 to 1 More preferably, it is in the range of / 2000.
[0033]
Furthermore, the isocyanate compound to be mixed is added in order to increase the adhesion between the base material 1 and the vapor-deposited thin film layer 2 made of an inorganic oxide by a urethane bond formed by reacting with an acrylic polyol. Acts as an 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 are used alone or as a mixture.
[0034]
The blending ratio of the acrylic 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, the blending ratio of the acrylic polyol and the insocyanate compound is preferably that the NCO group derived from the isocyanate compound is 50 times or less of the OH group derived from the acrylic polyol, and particularly preferably the NCO group and the OH group are blended in an equivalent amount. This is the case. As a mixing method, a known method can be used and is not particularly limited.
[0035]
Furthermore, in order to improve the liquid stability during preparation of the composite, it is possible to add a metal alkoxide or a hydrolyzate thereof. This metal alkoxide is tetraethoxysilane [Si (OC ₂ H _Five ) _Four ], Tripropoxy aluminum [Al (OC _Three H ₇ ) _Three ] General formula M (OR) _n (M is a metal such as Si, Al, Ti, Zr, R is CH _Three , C ₂ H _Five Or a hydrolyzate thereof.
Among 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 with the trifunctional organosilane, or a metal alkoxide hydrolyzate may be added.
[0036]
The mixing ratio of the trifunctional organosilane and the metal alkoxide is preferably in the range of 10: 1 to 1:10 in terms of molar ratio from the viewpoint of liquid stability. Preferably, both are blended in equimolar amounts.
[0037]
The composite film is obtained by hydrolyzing such trifunctional organosilane in advance or by hydrolyzing trifunctional organosilane together with metal alkoxide (in this case, the above-described reaction catalyst may be used. ) Is mixed with an acrylic polyol or an isocyanate compound to prepare a composite solution, or trifunctional organosilane and acrylic polyol are mixed in advance in a solvent (at this time, the above-mentioned reaction catalyst and metal alkoxide may be added. None) Hydrolyzed or mixed with trifunctional organosilane and acrylic polyol (in this case, the above-mentioned reaction catalyst or metal alkoxide may be added) and an isocyanate compound is added to form a composite A solution is prepared and coated on the substrate 1.
[0038]
Various additives such as tertiary amines, imidazole derivatives, metal salt compounds of carboxylic acids, quaternary ammonium salts, quaternary phosphonium salts and other curing accelerators, phenolic, sulfur-based, phosphite-based, etc. 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.
[0039]
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 0.01 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 due to external factors, which is not preferable. Particularly preferred is a range of 0.05 to 0.5 μm.
[0040]
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.
[0041]
The vapor-deposited thin film layer 3 made of an inorganic oxide is made of a vapor-deposited film of an inorganic oxide such as aluminum oxide, silicon oxide, tin oxide, magnesium oxide, or a mixture thereof, and has transparency and a gas barrier such as oxygen and water vapor. What is necessary is just to have. 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.
[0042]
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 the film formation. The thickness of the deposited thin film layer 3 is preferably in the range of 10 to 150 nm.
[0043]
There are various methods for forming the vapor-deposited thin film layer 3 made of an inorganic oxide on the transparent primer layer 2, and it can be formed by a normal vacuum vapor deposition method, but other thin film forming methods such as sputtering and ion plating. Alternatively, a plasma vapor deposition method (CVD) or the like can 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, an electron beam heating method, a resistance heating method, or an induction heating method is preferable. In order to improve the adhesion between the thin film and the base material 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 by blowing oxygen gas or the like during deposition.
[0044]
The gas barrier coating layer 4 is provided on the vapor-deposited thin film layer 3 made of an inorganic oxide in order to provide a gas barrier property as high as that of an aluminum foil depending on the required quality.
[0045]
The gas barrier coating layer 4 is mainly composed of an aqueous solution or a water / alcohol mixed solution containing at least one of a water-soluble polymer and (a) one or more metal alkoxides and hydrolysates or (b) tin chloride. It is formed using a coating agent. Mineralize a solution in which water-soluble polymer and tin chloride are dissolved in an aqueous (water or water / alcohol mixed) solvent, or a solution in which metal alkoxide is directly or hydrolyzed beforehand. The deposited thin film layer 3 made of oxide is formed by coating and heating and drying. Each component contained in the coating agent will be described in more detail.
[0046]
Examples of the water-soluble polymer used in the coating agent in the present invention include polyvinyl alcohol, polyvinyl pyrrolidone, starch, methyl cellulose, carboxymethyl cellulose, sodium alginate and the like. In particular, when polyvinyl alcohol (hereinafter abbreviated as PVA) is used as the coating agent of the laminate of the present invention, the gas barrier property is most excellent. PVA here is generally obtained by saponifying polyvinyl acetate, and includes from so-called partially saponified PVA in which several dozen percent of acetate groups remain to complete PVA in which only several percent of acetate groups remain. There is no particular limitation.
[0047]
Tin chloride is also stannous chloride (SnCl ₂ ), Stannic chloride (SnCl _Four ), Or a mixture thereof, and both anhydrides and hydrates can be used.
[0048]
Furthermore, the metal alkoxide is tetraethoxysilane [Si (OC ₂ H _Five ) _Four ], Triisopropoxyaluminum [Al (O-2′-C _Three H ₇ ) _Three ] General formula M (OR) _n (M: metal such as Si, Ti, Al, Zr, R: CH _Three , C ₂ H _Five Or an alkyl group such as Among these, tetraethoxysilane and triisopropoxyaluminum are preferable because they are relatively stable in an aqueous solvent after hydrolysis.
[0049]
Each of the above components can be added to the coating agent alone or in combination, and further, an isocyanate compound, a silane coupling agent, or a dispersant, stabilizer, viscosity adjustment, as long as the gas barrier properties of the coating agent are not impaired. Known additives such as coloring agents and coloring agents can be added.
[0050]
For example, the isocyanate compound added to the coating agent is one having two or more isocyanate groups (NCO groups) in the molecule. For example, monomers such as tolylene diisocyanate, triphenylmethane triisocyanate, and tetramethylxylene diisocyanate. And polymers and derivatives thereof.
[0051]
As a method for applying the coating agent, conventionally known means such as a dipping method, a roll coating method, a screen printing method, a spray method and the like that are usually used can be used. The thickness of the coating varies depending on the type of coating agent and the processing conditions, but it is sufficient that the thickness after drying is 0.01 μm or more. However, if the thickness exceeds 50 μm, cracks are likely to occur in the film. The range of 01-50 micrometers is preferable.
[0052]
Further, other layers can be laminated on the vapor-deposited thin film layer 3 and the gas barrier coating layer 4 made of an inorganic oxide. 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, etc., and various pigments are added to conventionally used ink binder resins such as urethane, acrylic, nitrocellulose, rubber and vinyl chloride. , A layer composed of an ink to which additives such as extender pigments, plasticizers, desiccants, stabilizers and the like are added, and characters, patterns, etc. are formed. As a forming method, 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 a roll coating, a knife edge coating, or a gravure coating can be used. The thickness may be 0.1 to 2.0 μm.
[0053]
The intermediate layer is provided to increase the bag breaking strength during boil and retort sterilization. Generally, from the viewpoint of mechanical strength and thermal stability, biaxially oriented nylon film, biaxially oriented polyethylene terephthalate film, biaxially oriented It is necessary to be a kind selected from polypropylene films. The thickness is determined according to the material, required quality, and the like, but is generally in the range of 10 to 30 μm. As a forming method, lamination can be performed by a known method such as a dry laminating method in which an adhesive such as a two-component curable urethane resin is used.
[0054]
The heat seal layer is provided as an adhesive layer when a bag-like package or the like is formed. For example, polyethylene, polypropylene, ethylene-vinyl acetate copolymer, ethylene-methacrylic acid copolymer, ethylene-methacrylic acid ester copolymer, ethylene-acrylic acid copolymer, ethylene-acrylic acid ester copolymer and their metals A resin such as a cross-linked product is used. The thickness is determined according to the purpose, but is generally in the range of 15 to 200 μm. As a forming method, it is common to use a dry laminating method or the like in which a film-like material made of the above resin is bonded using an adhesive such as a two-component curable urethane resin. be able to.
[0055]
【Example】
The strong adhesion gas barrier transparent laminate of the present invention and the package using the same will be further described with specific examples, but are not limited to these examples without departing from the gist of the present invention. .
[0056]
<Preparation of complex solution>
A) In a diluting solvent, 2- (epoxycyclohexyl) ethyltrimethylsilane (hereinafter abbreviated as EETMS) and acrylic polyol were mixed in an amount of 5.0 times (weight ratio) with respect to EETMS, and further tin chloride (SnCl) as a catalyst. ₂ ) / Methanol solution (prepared at 0.003 mol / g) is added to EETMS to 1/135 mol and stirred. Subsequently, a mixed solution obtained by diluting a mixed solution of triisyl isocyanate (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.
[0057]
B) EETMS and tetraethoxysilane (Si (OC ₂ H _Five ) _Four : Abbreviated as TEOS below) and a mixture with a molar ratio of 1: 1, and acrylic polyol is taken 2.5 times by weight with respect to a mixture of EETMS and TEOS, and chlorinated as a catalyst. Tin (SnCl ₂ ) / Methanol solution (prepared to 0.003 mol / g) is added to a mixture of EETMS and TEOS so as to be 1/400 mol and stirred. 0.1 N HCl was added thereto, stirred and hydrolyzed, and then a mixed solution obtained by diluting the mixed solution of TDI so that the NCO group was equivalent to the OH group of the acrylic polyol to an arbitrary concentration is used as a composite solution B.
[0058]
C) In a dilute solvent, EETMS and TEOS mixed at a molar ratio of 1: 1 are mixed with acrylic polyol at a weight ratio of 2.5 times that of TEOS and EETMS. A composite solution C is prepared by diluting a mixed solution in which TDI is added to OH groups of acrylic polyol so that the amount of NOC groups is equal to that of acrylic polyol to an arbitrary concentration.
[0059]
D) In a diluting solvent, TDI as an isocyanate compound is added to the acrylic polyol so as to have an equivalent amount with respect to the OH group of the acrylic polyol, and the diluted solvent is added to obtain a composite solution D.
[0060]
<Example 1>
A composite solution A as a transparent primer layer 2 having a thickness of 0.2 μm was formed on one side of a biaxially stretched polyethylene terephthalate (PET) film having a thickness of 12 μm as the substrate 1 by a gravure coating method. Next, the vapor deposition thin film layer 3 made of an inorganic oxide is obtained by evaporating metal aluminum on the transparent primer layer 2 by an electron beam heating vacuum deposition apparatus, introducing oxygen gas therein, and depositing 20 nm thick aluminum oxide. Formed. Further, a coating agent having the following composition was applied thereon with a bar coater, dried at 120 ° C. for 1 minute with a dryer to form a gas barrier coating layer 4 having a thickness of 0.3 μm, and the strong adhesion gas barrier transparent laminate of the present invention was formed. Obtained.
Composition of coating agent: A mixture of the following (1) liquid and the following (2) liquid in a mixing ratio (wt% / wt%) to 60/40.
(1) Solution: 89.6 g of hydrochloric acid (0.1N) was added to 10.4 g of tetraethoxysilane, and the mixture was stirred for 30 minutes to hydrolyze and solid content was 3 wt% (SiO 2 ₂ Conversion) hydrolysis solution.
(2) Solution: 3 wt% water / isopropyl alcohol solution of polyvinyl alcohol (90:10 by weight ratio of water: isopropyl alcohol).
[0061]
<Example 2>
In Example 1, the strong adhesion of the present invention was the same as in Example 1 except that silicon oxide having a thickness of about 40 nm was deposited as a vapor deposition thin film layer 3 made of an inorganic oxide by a vacuum deposition method using a resistance heating method (not shown). A gas barrier transparent laminate was obtained.
[0062]
<Example 3>
A strong adhesion gas barrier transparent laminate of the present invention was obtained in the same manner as in Example 1 except that the composite solution B was used as the transparent primer layer 2 in Example 1.
[0063]
<Example 4>
A strong adhesion gas barrier transparent laminate of the present invention was obtained in the same manner as in Example 1 except that the composite solution C was used as the transparent primer layer 2 in Example 1.
[0064]
<Comparative example 1>
A transparent laminate was obtained in the same manner as in Example 1 except that the transparent primer layer 2 was not provided in Example 1.
[0065]
<Comparative example 2>
In Example 1, the transparent laminated body was obtained like Example 1 except having used the composite solution D as a transparent primer layer.
[0066]
Next, as a middle layer on the gas barrier coating layer 4 of the strong adhesion gas barrier transparent laminate obtained in Examples 1 to 4, a biaxially stretched nylon film having a thickness of 15 μm is coated with a two-component curable urethane adhesive. In addition, the present invention of Examples 1 to 4 was performed by laminating a polypropylene film having a thickness of 40 μm as a polyolefin-based thermoplastic resin layer by a dry-laminating method via a two-component curable urethane adhesive as a polyolefin-based thermoplastic resin layer. A strong adhesion gas barrier transparent laminate was prepared.
Similarly, a biaxially stretched nylon film having a thickness of 15 μm is interposed as an intermediate layer on the gas barrier coating layer 4 of the transparent laminate obtained in Comparative Examples 1 and 2 via a two-component curable urethane adhesive. Laminated by the dry laminating method, and further laminated as a polyolefin-based thermoplastic resin layer by a dry laminating method with a polypropylene film having a thickness of 40 μm via a two-component curable urethane adhesive, the transparent laminates of Comparative Examples 1 and 2 Produced.
[0067]
<Test 1>
A four-way pouch was prepared for retort sterilization using the strong adhesion gas barrier transparent laminate of the present invention of Examples 1 to 4 and the transparent laminate of Comparative Examples 1 and 2 produced in this manner, and water was used as the content. 150 g was filled, and retort sterilization was performed at 90 ° C. for 30 minutes. As an evaluation, oxygen permeability before and after retort (cc / m ² / Day), the laminate strength (gr / 15 mm), and the delamination occurrence after retorting were observed by visual observation. The results are shown in Table 1.
In Table 1, the result of evaluation of the appearance after retorting ◎ indicates that no delamination has occurred, ○ indicates that no delamination has occurred, and × indicates that delamination has occurred. The overall evaluation results in Table 1 indicate that ◎ is very good, ○ is good, and × indicates that it cannot be used.
[0068]
[Table 1]

[0069]
From Table 1, the strong adhesion gas barrier transparent laminates of the present invention of Examples 1 to 4 and the packaging body (pouch) using the same have transparency that allows the contents to be directly seen through, and the contents. Retort resistance that has high gas barrier properties and high laminate strength to block gases that affect the gas, and does not deteriorate after the retort, maintains high laminate strength, and does not cause delamination. It turns out that it has sex.
On the other hand, the transparent laminated body of Comparative Examples 1 and 2 and the packaging body (pouch) using the same have transparency capable of directly seeing through the contents, and before the retort, gas etc. that affect the contents It has gas barrier properties to block and high laminate strength, but after retorting, the gas barrier properties are deteriorated, the laminate strength is lowered, delamination occurs, and the retort resistance is poor.
[0070]
【The invention's effect】
The strong adhesion gas barrier transparent laminate of the present invention and a package using the same are provided with a transparent primer layer having excellent dimensional stability and adhesion even after boil sterilization and retort sterilization on a transparent plastic substrate. Because it has a structure in which a vapor-deposited thin film layer made of an excellent inorganic oxide is laminated, it has transparency that allows the contents to be seen directly, and has an advanced gas barrier property similar to that of aluminum foil. In addition, after boil sterilization and retort sterilization, there is no generation of delamination and gas barrier property deterioration, and it can be widely used in the packaging field as packaging materials for general-purpose foods, non-foods, and pharmaceuticals.
[Brief description of the drawings]
FIG. 1 is a partial cross-sectional view of an embodiment of a strongly bonded gas barrier transparent laminate of the present invention.
[Explanation of symbols]
1 Base material made of transparent plastic material
2 Transparent primer layer
3 Deposition thin film layer made of inorganic oxide
4 Gas barrier coating layer

Claims (13)

A trifunctional organosilane represented by the general formula R′Si (OR) ₃ (R ′: alkyl group, vinyl group, glycidoxypropyl group, R: alkyl group, etc.) on at least one surface of a substrate made of a transparent plastic material Alternatively, a strong adhesion characterized by sequentially laminating a hydrolyzate of the organosilane, a transparent primer layer composed of a composite of acrylic polyol and an isocyanate compound, and a deposited thin film layer composed of an inorganic oxide having a thickness of 5 to 300 nm. Gas barrier transparent laminate. The strong adhesion gas barrier transparent laminate according to claim 1, wherein an epoxy group is contained in R ′ constituting the trifunctional organosilane. The strong adhesion gas barrier transparent laminate according to claim 1, wherein a reaction catalyst is added to the composite. 4. The strong adhesion gas barrier transparent laminate according to claim 3, wherein the reaction catalyst is a tin compound. The strong adhesion gas barrier transparent laminate according to claim 4, wherein the tin compound is a tin compound selected from tin chloride, tin oxychloride and tin alkoxide. In the composite, a metal alkoxide represented by the general formula M (OR) _n (M: metal element, R: alkyl group such as CH ₃ , C ₂ H ₅ , n: oxidation number of metal element) or The strongly bonded gas barrier transparent laminate according to any one of claims 1 to 5, wherein a hydrolyzate of the metal alkoxide is added. 7. The strong adhesion gas barrier transparent according to claim 1, wherein the metal in the metal alkoxide or the hydrolyzate of the metal alkoxide is Si, Al, Ti, Zr or a mixture thereof. Laminated body. The thickness of the said transparent primer layer is the range of 0.01-2 micrometers, The strongly-adhesion gas barrier transparent laminated body in any one of Claims 1-7 characterized by the above-mentioned. The strong adhesion gas barrier transparent laminate according to any one of claims 1 to 8, wherein the inorganic oxide is aluminum oxide, silicon oxide, magnesium oxide, or a mixture thereof. A gas barrier coating layer is further laminated on the strong adhesion gas barrier transparent laminate, and the gas barrier coating layer comprises a water-soluble polymer, (a) one or more metal alkoxides and a hydrolyzate thereof. Or (b) a layer formed by applying a coating agent mainly composed of an aqueous solution containing at least one of tin chloride or a water / alcohol mixed solution, followed by drying by heating. The strong adhesion gas barrier transparent laminated body in any one. The strong adhesion gas barrier transparent laminate according to claim 10, wherein the metal alkoxide is tetraethoxysilane, triisopropoxyaluminum, or a mixture thereof. The strong adhesion gas barrier transparent laminate according to claim 10 or 11, wherein the water-soluble polymer is polyvinyl alcohol. A package produced using the strong adhesion gas barrier transparent laminate according to any one of claims 1 to 12.

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