JP4114404B2 - Method for producing gas barrier transparent conductive laminated film - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for producing a gas barrier film used as a packaging material for foods, pharmaceuticals, electronic parts, etc., and in particular, an inorganic oxide vapor deposition layer is formed on a transparent plastic substrate in the same film forming step. immediately after, the transparent conductive evaporated layer formed by forming a metal deposition layer, a method of manufacturing a gas barrier transparent conductive laminate fill arm used as transparency, gas barrier layer having conductivity.
[0002]
[Prior art]
In recent years, packaging materials used for packaging foods, non-foods, etc. have altered the contents, oxygen, water vapor, and other contents that permeate the packaging materials in order to suppress their alteration and retain their functions and properties. It is necessary to prevent the influence of gas, and it is required to have a gas barrier property that blocks these gases. Furthermore, when the contents are stored for a long period of time, it is required that the laminate strength is not deteriorated by the contents in order to maintain gas barrier properties and function as a packaging material. 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, a packaging material using a metal foil made of a metal such as aluminum has excellent gas barrier properties and little deterioration in laminate strength over time, but the contents cannot be confirmed through the packaging material. When disposing, there is a problem in that it has to be treated as an incombustible material and a metal detector cannot be used.
[0004]
Therefore, as a packaging material that overcomes these drawbacks, there is a film in which an inorganic oxide such as silicon oxide, aluminum oxide, tin oxide or the like is formed on a polymer film by a deposition method such as vacuum deposition or sputtering. Has been developed. These 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 by metal vapor deposition films. .
[0005]
Furthermore, in recent years, transparent gas barrier conductive films in which conductivity is imparted to gas barrier packaging materials have been developed. For example, as a transparent gas barrier conductive film, a gas barrier in which a transparent inorganic oxide such as aluminum oxide is provided as a gas barrier layer on one or both surfaces of a transparent plastic film such as polyethylene terephthalate (PET). In order to create a film and to make this gas barrier film conductive, a gas barrier layer made of a transparent inorganic oxide such as aluminum oxide was further laminated with a metal vapor deposition layer such as metal aluminum in a separate process, It is actually being used.
[0006]
Such a transparent gas barrier conductive film comprises a gas barrier layer made of a gas barrier polymer such as polyvinylidene chloride (PVDC), ethylene / vinyl acetate copolymer (EVA), or ethylene / vinyl alcohol copolymer (EVOH). Compared to those used in the above, it has an excellent feature that it has a high barrier property against both oxygen and water vapor, and its change due to temperature and humidity is small. In addition, for those using aluminum foil or an aluminum vapor deposition layer as a gas barrier layer, the transparency is high and the contents can be seen through and confirmed, and the contents inspection by a metal detector is also possible. It has something.
[0007]
[Problems to be solved by the invention]
However, in order to impart conductivity to a transparent gas barrier laminate film using such an inorganic oxide layer such as aluminum oxide as a gas barrier layer, conventionally, as described above, polyethylene terephthalate (PET) is used. A gas barrier film in which a transparent inorganic oxide such as aluminum oxide is provided as a gas barrier layer on one side or both sides of a film such as a transparent plastic is once prepared. Since the gas barrier layer is formed by two steps of laminating a metal vapor deposition layer such as metal aluminum, the production efficiency is low, that is, there is a problem in terms of manufacturing cost.
[0008]
An object of the present invention is to solve problems in production of such a conventional transparent gas barrier conductive laminated film, in particular. In other words, food and electronic parts high barrier properties are required, has a high barrier property even with the available levels for packaging applications, such as pharmaceuticals, has the great advantage in terms of production costs, the production of gas barrier transparent conductive laminate fill arm It is intended to provide a method.
[0009]
[Means for Solving the Problems]
The present invention is for achieving the above object, and the invention according to claim 1 is a long transparent plastic film substrate 64 continuously moving from the unwinding roll 61 to the winding roll 63. The aluminum vapor obtained by heating and vaporizing the vapor deposition material 67 housed in the crucible 66 provided below the film-forming roll 65 at a position passing through the film-forming roll 65 is used as the film-forming roll (cooling roll) 65. In the method for producing a vapor deposition film in which an aluminum oxide vapor deposition layer is provided by reacting with oxygen supplied from an oxygen supply pipe 72 provided between crucibles 66,
A partition plate 70 for blocking oxygen and partitioning the aluminum oxide deposition zone and the aluminum deposition zone is provided on the winding roll 63 side of the oxygen supply pipe 72 to continuously form the aluminum oxide deposition layer and the aluminum deposition layer. Is a method for producing a gas barrier transparent conductive laminated film.
[0010]
The invention according to claim 2 is the method for producing a gas barrier transparent conductive laminated film according to claim 1 , wherein the partition plate 70 is movable.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 shows an example of a cross-sectional view of a gas barrier transparent conductive laminated film in the present invention. This gas barrier transparent conductive laminated film 10 is formed on the transparent plastic film substrate 20 in the same film forming step, immediately after forming the aluminum oxide vapor deposition layer 30 as an inorganic oxide vapor deposition layer, almost simultaneously as a metal vapor deposition layer. The transparent conductive deposition layer 50 formed by forming the aluminum deposition layer 40 functions as a gas barrier layer having transparency and conductivity.
[0012]
As the transparent plastic film substrate 20 used in the present invention, nylon, polyethylene, polypropylene, polyvinyl chloride, polycarbonate, polyvinyl alcohol, cellulose, polyacrylate, polyurethane, cellophane, polyethylene Examples include stretched or unstretched films such as terephthalate, polyethylene naphthalate, polyethersulfone, and ionomer. Use environment of gas barrier transparent conductive laminated film, type of package, processability and economy, etc. Is selected as appropriate.
[0013]
Although the thickness of such a base material is also determined in consideration of the above, a thickness of about 10 to 100 μm is generally used. In order to further improve the adhesion to the transparent conductive oxide layer on the surface of such a plastic film substrate, the surface of corona treatment, low temperature plasma treatment, ion bombardment treatment, chemical treatment, solvent treatment, etc. It does not matter even if it has been treated.
[0014]
Next, an example of a film forming method of the transparent conductive vapor deposition layer 50 in the present invention will be described using a vacuum film forming apparatus or the like. An electron beam heating type vacuum winding deposition apparatus 60 shown in FIG. 2 deposits on an unwinding roll 61 on which a long transparent plastic film substrate 64 is disposed, and on the long transparent plastic film substrate 64. The film-forming roll (cooling roll) 65 is provided between the winding roll 63 for winding the deposited film and the winding roll 61 and the winding roll 63. Below the film forming roll 65, for example, a crucible 66 containing an aluminum vapor deposition material 67 and an electron gun 68 for heating and vaporizing the vapor deposition material 67 in the crucible 66 are provided. An oxygen supply pipe 72 is provided between the film forming roll (cooling roll) 65 and the crucible 66, and an aluminum oxide vapor deposition zone a and an aluminum vapor deposition zone are disposed on the winding roll 63 side of the oxygen supply pipe 72. A partition plate 70 for partitioning into b is provided. The partition plate 70 is movable left and right by a partition plate control device 71.
[0015]
Next, the manufacturing method of the gas barrier transparent conductive laminated film using the said electron beam heating type vacuum winding vapor deposition apparatus 60 is demonstrated. First, the transparent conductive vapor-deposited layer 50 is placed on a long transparent plastic film substrate 64 that continuously moves from the unwinding roll 61 to the winding roll 63 at a position where the film-forming roll (cooling roll) 65 passes. Form. In the transparent conductive vapor deposition layer 50, aluminum vapor obtained by heating and vaporizing the aluminum vapor deposition material 67 in the crucible 66 by the electron beam 69 emitted from the electron gun 68 was supplied from the oxygen supply pipe 72. Aluminum oxide oxidized by oxygen and aluminum not oxidized by oxygen are continuously formed. At this time, the transparent conductive vapor deposition layer 50 can control the thickness ratio of the vapor deposition film of aluminum oxide and aluminum by moving the partition plate 70 left and right.
[0016]
The partition plate is not particularly limited, but the length is preferably about 5 to 20 cm.
[0017]
The aluminum oxide vapor deposition layer 30 constituting the transparent conductive vapor deposition layer 50 in the present invention functions as a gas barrier, while the metal aluminum vapor deposition layer 40 imparts conductivity. Since the metal aluminum vapor deposition layer 40 can be formed almost immediately after the formation of the aluminum oxide vapor deposition layer 30 in the same film forming process, the production efficiency is excellent and the manufacturing cost can be greatly reduced. Furthermore, a partition plate 70 that partitions the aluminum oxide vapor deposition zone a and the aluminum vapor deposition zone b is provided, and the vapor deposition ratio of aluminum oxide and metal aluminum can be controlled by a control device 71 that allows the partition plate 70 to move left and right. Therefore, the gas barrier transparent conductive laminated film of the present invention can easily control various gas barrier properties and conductivity, and can be used for a wide range of applications.
[0018]
Although there is no restriction | limiting in particular in the thickness of the metal aluminum vapor deposition layer which provides electroconductivity, In order to obtain the surface resistance value as low as possible, the thicker one is preferable. However, the formation of a thick film is not preferable in terms of productivity, and if it is too thick, cracking may occur due to internal stress of the film, or coloring may become remarkable.
[0019]
The transparent conductive thin film layer made of aluminum oxide and metal aluminum can be formed by sputtering, CVD, ion plating, etc. in addition to vacuum evaporation using electron beam heating, induction heating, and resistance heating as evaporation means. Although it can be used, a method of forming a film on a wound film using a vacuum deposition method is preferable from the viewpoint of productivity.
[0020]
Moreover, it is a particularly preferable method to continuously form a film in the same vacuum chamber without opening to the atmosphere after forming the transparent conductive thin film layer. By continuously forming the film, it is possible to prevent water molecules from adsorbing on the surface of the transparent conductive thin film layer, and the barrier property due to the water molecules being taken into the gas barrier layer made of aluminum oxide and metal aluminum. This is because the adverse effect on the water vapor barrier property can be prevented. Furthermore, continuous film formation in the same vacuum chamber can save time for evacuation and the like, which is a great advantage in terms of manufacturing cost.
[0021]
The thickness of such a transparent conductive thin film layer made of aluminum oxide and metal aluminum is slightly different depending on the composition of this layer, but is in the range of 5 to 100 nm, more preferably in the range of 10 to 50 nm. is there. If the thickness is less than 5 nm, a continuous layer may not be formed. Conversely, if the thickness is more than 100 nm, cracks are likely to occur due to internal stress.
[0022]
In the present invention, a primer layer may be provided on at least one surface of the plastic substrate, if necessary, for the purpose of improving the adhesion when the thin film layer is formed.
[0023]
In order to achieve the above object, the primer resin can be used as a polyester resin alone or a mixture of the resin and one or more mixed resins selected from an isocyanate resin, an epoxy resin, and a melamine resin. There must be.
[0024]
The above polyester resins are terephthalic acid, isophthalic acid, phthalic acid, methylphthalic acid, trimellitic acid, pyromellitic acid, adipic acid, sebacic acid, succinic acid, maleic acid, fumaric acid, tetrahydrophthalic acid, methyltetrahydrophthalic acid, hexahydro Acid raw materials such as phthalic acid and reactive derivatives thereof, ethylene glycol, propylene glycol, 1,3-butanediol, 1,4-butanediol, 1,6-hexanediol, diethylene glycol, dipropylene glycol, 1,4 -Cyclohexanedimethanol, neopentyl glycol, isopentyl glycol, bishydroxyethyl terephthalate, hydrogenated bisphenol A, alkylene oxide adduct of hydrogenated bisphenol AA, trimethylolethane, trimethylol Although what was manufactured by the well-known method from alcohol raw materials, such as lopan, glycerin, pentaerythritol, 2,2,4-trimethylpentane-1,3-diol, can be used, it does not specifically limit to these. .
[0025]
The mixed resin added to the polyester resin is added to further improve the adhesion, and mainly acts as a crosslinking agent or a curing agent. To achieve this, mixed resins include isocyanate resins such as tolylene diisocyanate (TDI), xylene diisocyanate (XDI), hexadiisocyanate (MDI), bisphenol A diglycine ether type epoxy and hydrogenated bisphenol type epoxy. Epoxy resins, melamine resins, and mixtures of one or more of these can be used. Among them, the case of using an isocyanate-based resin (particularly TDI) is preferable because it has the best adhesion.
[0026]
As a mixing ratio of the polyester resin and the mixed resin, an isocyanate group, an epoxy group, an amino group, or the like may be contained in an equivalent amount or more with respect to the OH group or COOH group of the polyester resin. For example, when an isocyanate resin alone is used as a mixed resin, the blending ratio of the polyester resin and the isocyanate resin is in the range of 1: 0.5 to 1:20 in terms of (OH group of polyester) :( NCO group of isocyanate). It is desirable. If it is equal to or less than the equivalent, there will be a problem in adhesion due to poor curing and insufficient crosslinking. However, adding too much is not preferable because the added resin does not react and the remaining film is adversely affected. About the method of mixing, a well-known method can be used and it does not specifically limit.
[0027]
The organic solvent for dissolving the primer resin is not particularly limited as long as the resin can be dissolved, for example, esters such as ethyl acetate and butyl acetate, ketones such as methyl ethyl ketone and methyl isobutyl ketone, Aromatic hydrocarbons such as toluene and xylene can be used alone or arbitrarily blended. A mixture of toluene and methyl ethyl ketone is preferable from the viewpoint of coating film processing and odor.
[0028]
Various additives such as tertiary amines, imidazole derivatives, carboxylic acid metal salt compounds, quaternary ammonium salts, quaternary borophonium salts, etc., primer-based, sulfur-based, phosphite-based, etc. Antioxidants, leveling agents, flow regulators, catalysts, crosslinking reaction accelerators, fillers, and the like can be added.
[0029]
The thickness of the transparent primer layer is not particularly limited as long as a uniform coating film can be formed, but is generally in the range of 0.01 μm to 1.0 μm, particularly preferably in the range of 0.1 μm to 0.5 μm. Preferably there is.
[0030]
As a method for forming the transparent primer layer, 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 can be used. . About drying conditions, generally used conditions may be used.
[0031]
Furthermore, in this invention, the gas barrier coating layer demonstrated below can also be provided in the surface of the transparent conductive vapor deposition layer 50 as needed.
[0032]
The gas barrier coating layer is provided on the inorganic oxide thin film layer to provide a gas barrier property as high as that of an aluminum foil, and includes a water-soluble polymer, (a) one or more metal alkoxides, and It consists of a coating agent mainly composed of an aqueous solution containing at least one of a hydrolyzate or (b) tin chloride, or a water / alcohol mixed solution. 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 has been directly or previously hydrolyzed. The oxide thin film layer 3 is formed by coating and heating and drying. Each component contained in the coating agent will be described in more detail.
[0033]
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, and sodium alginate. In particular, when polyvinyl alcohol (hereinafter referred to as PVA) is used for the coating agent of the laminate of the present invention, gas barrier properties are most excellent. The 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.
[0034]
The tin chloride may be stannous chloride (SnCl ₂ ), stannic chloride (SnCl ₄ ), or a mixture thereof, and may be used as an anhydride or a hydrate.
[0035]
Further, the metal alkoxide may be a general formula such as tetraethoxysilane [Si (OC ₂ H ₅ ) ₄ ], triisopropoxyaluminum [Al (O-2′-C ₃ H ₇ ) ₃ ], M (OR) _n (M : Metal such as Si, Ti, Al and Zr, R: alkyl group such as CH ₃ and C ₂ H ₅ ). Among these, tetraethoxysilane and triisopropoxyaluminum are preferable because they are relatively stable in an aqueous solvent after hydrolysis.
[0036]
Each of the above-mentioned components can be added to the coating agent alone or in combination, and an isocyanate compound, a silane coupling agent, or a dispersant, a stabilizer, and a 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.
[0037]
For example, the isocyanate compound added to the coating agent has two or more isocyanate groups (NCO groups) in the molecule, such as tolylene diisocyanate (hereinafter TDI), triphenylmethane triisocyanate (hereinafter TTI), There are monomers such as tetramethylxylene diisocyanate (hereinafter TMXDI), and polymers and derivatives thereof.
[0038]
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 film 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 is 50 μm or more, the film is likely to crack. It is preferably in the range of ˜50 μm.
[0039]
By using the primer layer and the gas barrier coating layer described above, by providing at least one of the primer layer on the transparent plastic substrate surface of the transparent conductive laminated film of the present invention and the gas barrier coating layer on the transparent conductive vapor deposition layer, High adhesion that does not deteriorate the adhesion between the base material and the vapor deposition layer due to the content of the material, and high gas barrier properties that block the gas that affects the content, etc., excellent transparency, and It is possible to provide a highly practical gas barrier transparent conductive laminated film having high gas barrier properties and excellent adhesion without deterioration of laminate strength. Therefore, it has a high level of barrier properties that can be used for packaging applications such as foods, electronic parts, and pharmaceuticals that require high barrier properties. In addition to packaging applications for parts, pharmaceuticals, etc., it can be used in a wide range of fields as a highly functional film.
[0040]
【The invention's effect】
As described above, according to the present invention, a metal vapor deposition layer such as aluminum is formed almost immediately after forming an inorganic oxide vapor deposition layer such as aluminum oxide on the transparent plastic film substrate in the same film forming step. the formed transparent conductive deposited layer formed by using as a gas barrier layer, has the great advantage in terms of manufacturing cost, it is possible to provide a manufacturing method for the gas-barrier transparent conductive laminate fill beam. The gas barrier transparent conductive laminated film of the present invention has a high level of barrier properties that can be used for packaging applications such as foods, electronic parts, and pharmaceuticals that require high barrier properties, and also has high transparency and conductivity. As a functional film, it can be developed in a wide range of fields as a highly functional film in addition to packaging for food, electronic parts, pharmaceuticals and the like.
[Brief description of the drawings]
It is a cross-sectional view showing an embodiment of the transparent gas barrier laminated film in the present invention; FIG.
FIG. 2 is a cross-sectional view schematically showing a winding deposition state of the vacuum film forming apparatus of the present invention .
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Gas barrier transparent conductive laminated film 20 ... Transparent plastic base material 30 ... Aluminum oxide vapor deposition layer 40 ... Aluminum vapor deposition layer 50 ... Transparent conductive vapor deposition layer 60 ... Vacuum film-forming apparatus 61 ... Unwinding roll 62 ... Guide roll 63 ... Winding roll 64 ... long transparent plastic film substrate 65 ... film forming roll 66 ... crucible 67 ... vapor deposition material 68 ... electron gun 69 ... electron beam 70 ... partition plate 72 ... oxygen supply pipe 73 ... Vacuum pump 74 ... aluminum vapor 75 ... oxygen gas atmosphere 76 ... aluminum oxide vapor a ... aluminum oxide vapor deposition zone b ... aluminum vapor deposition zone

Claims (2)

A crucible provided below the film-forming roll 65 at a position where the film-forming roll 65 passes through a long transparent plastic film substrate 64 that continuously moves from the winding roll 61 to the winding roll 63. The aluminum vapor obtained by heating and vaporizing the vapor deposition material 67 housed in 66 is reacted with oxygen supplied from an oxygen supply pipe 72 provided between the film-forming roll (cooling roll) 65 and the crucible 66 to deposit aluminum oxide. In the manufacturing method of the vapor deposition film which provides a layer,
A partition plate 70 for blocking oxygen and partitioning the aluminum oxide deposition zone and the aluminum deposition zone is provided on the winding roll 63 side of the oxygen supply pipe 72 to continuously form the aluminum oxide deposition layer and the aluminum deposition layer. The manufacturing method of the gas barrier transparent conductive laminated film characterized by these. The said partition plate 70 is movable, The manufacturing method of the gas barrier transparent conductive laminated film of Claim 1 characterized by the above-mentioned.

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