JP2006142741A - Gas barrier laminated film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a transparent gas barrier laminated film not lowered in its gas barrier properties even if various post-processings such as printing, lamination, bag making and the like are applied. <P>SOLUTION: In the gas barrier laminated film constituted by laminating a vapor deposition thin film layer comprising aluminum oxide or the like and at least two gas barrier film layers, of which the total thickness of 0.02-20 μm, on one side of a base material layer, at least two gas barrier film layers are constituted by laminating at least two uncured flash vapor deposition film layers, each of which comprises an acrylic monomer containing at least one of a monoacrylate, a diacrylate and a triacrylate or a mixture of the monomer and an oligomer and subsequently irradiating both layers with ultraviolet rays or an electron beam to cure them at the same time. The viscosity of the monomer or the mixture is 200 mPa s/25°C and the surface of the vapor deposition film layers and/or the outermost surface of the gas barrier film layers is subjected to plasma treatment. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a gas barrier laminated film used in the field of packaging of foods, daily necessities, pharmaceuticals, etc. or the field of electronic equipment-related members.

Packaging materials used for the packaging of food, daily necessities, pharmaceuticals, etc. contain oxygen, water vapor, etc. that permeate the contents so as to suppress the alteration of the contents and maintain their functions and properties even during packaging. It is necessary to prevent the influence by the gas which changes the thing, and it is calculated | required that the gas barrier property which interrupts | blocks these is provided. As packaging materials having ordinary gas barrier properties, vinylidene chloride resin films or films coated with vinylidene chloride resins, which are excellent in gas barrier properties among polymers, have been often used, but these have high gas barrier properties. It cannot be used for the required packaging. Therefore, when there is such a request, a packaging material using a metal foil such as aluminum as a gas barrier layer has to be used. However, packaging materials using metal foils such as aluminum have almost no influence of temperature and humidity, and have high gas barrier properties, but the contents cannot be confirmed through the packaging material, after use. However, the metal detector must be treated as an incombustible material at the time of disposal, and the metal detector cannot be used at the time of inspection. Therefore, as a packaging material that overcomes these drawbacks, there is a vapor deposition film formed by laminating a vapor-deposited thin film layer and a gas barrier coating layer of an inorganic oxide such as silicon oxide, aluminum oxide, and magnesium oxide on a base layer made of a plastic film. (For example, refer to Patent Document 1).
Japanese Patent Application Laid-Open No. 07-164591

  However, the proposed vapor deposition film has the disadvantage that the gas barrier properties such as oxygen permeability and water vapor permeability are deteriorated when various post-processing such as printing, laminating and bag making are performed. It was.

  The subject of this invention is providing the transparent laminated | multilayer film which gas barrier property does not fall even if various post-processes, such as printing, lamination, and bag making, are given.

  The invention according to claim 1 of the present invention is a gas barrier laminate film in which a vapor-deposited thin film layer made of an inorganic oxide and two or more gas barrier coat layers are laminated on at least one side of a base material layer made of a transparent plastic film. The two or more gas barrier coating layers are laminated with two or more uncured flash vapor deposition coating layers composed of acrylic monomers or a mixture of monomers and oligomers on the vapor deposition thin film layer, and then irradiated with ultraviolet rays or electron beams. A gas barrier laminate film comprising two or more flash-deposited coating layers cured simultaneously.

  The invention according to claim 2 of the present invention is the invention according to claim 1, wherein the acrylic monomer or a mixture of monomer and oligomer contains at least one of monoacrylate, diacrylate, and triacrylate. This is a gas barrier laminate film.

The invention according to claim 3 of the present invention is the invention according to claim 1 or 2, wherein the acrylic monomer or the mixture of the monomer and the oligomer has a viscosity of 200 mPa · s / 25 ° C. or less. It is a gas barrier laminate film.

  The invention according to claim 4 of the present invention is the invention according to any one of claims 1 to 3, wherein the total film thickness of the two or more gas barrier coating layers is 0.02 to 20 μm. It is a gas barrier laminate film characterized by being.

  The invention according to claim 5 of the present invention is the invention according to any one of claims 1 to 4, wherein the inorganic oxide is silicon oxide, aluminum oxide, magnesium oxide or a mixture thereof. It is a gas-barrier laminated film characterized.

  The invention according to claim 6 of the present invention is the invention according to any one of claims 1 to 5, wherein the outermost surface of the deposited thin film layer and / or the gas barrier coating layer is subjected to plasma treatment. A gas barrier laminate film.

  The gas barrier laminate film of the present invention has a total film thickness of 0.02 to 20 μm on a thin film layer made of silicon oxide, aluminum oxide, magnesium oxide or a mixture thereof on at least one side of a base material layer made of a transparent plastic film. A gas barrier laminate film in which two or more gas barrier coating layers are laminated, wherein the two or more gas barrier coating layers are an uncured flash vapor deposition coating layer comprising an acrylic monomer or a mixture of a monomer and an oligomer. Since two or more layers of the flash vapor deposition coating layer are simultaneously cured by irradiating with ultraviolet rays or electron beams after laminating two or more layers on the vapor deposition thin film layer, it is transparent and has an excellent gas barrier property. The adhesion strength between each layer of two or more gas barrier coating layers is very strong. Gas barrier properties and the like is not lowered even if processing is given after. Further, the acrylic monomer or the mixture of the monomer and the oligomer comprises at least one of monoacrylate, diacrylate, and triacrylate, and the viscosity of the acrylic monomer or the mixture of the monomer and the oligomer is 200 mPa · Since it is s / 25 ° C. or less, it has good adhesion to the deposited thin film layer and is efficient in forming the flash deposited film layer. Further, the surface of the deposited thin film layer and the outermost surface of the gas barrier film layer are plasma. The treatment improves the adhesion strength between the vapor-deposited thin film layer and the gas barrier coating layer and the adhesion strength between the gas barrier coating layer and other layers, and uncured components remain on the outermost surface of the gas barrier coating layer. There is no hygiene. Therefore, it can be widely used in the field of packaging such as food and non-food, or the field of electronic equipment-related members.

  The gas barrier laminate film of the present invention will be described along the embodiments. FIG. 1 is a side cross-sectional view showing an embodiment of a gas barrier laminate film of the present invention. A base material layer (1), a vapor-deposited thin film layer (2) made of an inorganic oxide, and a gas barrier coating layer are sequentially arranged in the thickness direction. A gas barrier coating layer (3) having a two-layer structure of (3a) and a gas barrier coating layer (3b) is laminated.

  The substrate layer (1) is made of a transparent plastic film. Examples of the plastic film include a polyester film made of polyethylene terephthalate (PET), polyethylene naphthalate, etc., and a polyolefin film made of polyethylene, polypropylene, etc. Biodegradable plastic films such as polystyrene film, polyamide film, polyvinyl chloride film, polycarbonate film, polyacrylonitrile film, polyimide film, and polylactic acid film are used. These films may be either stretched or unstretched, but those having mechanical strength and dimensional stability are preferred. Among these, a polyethylene terephthalate film arbitrarily stretched in a biaxial direction from the viewpoint of heat resistance and dimensional stability is preferably used.

  The base material layer (1) may be a film containing various additives such as an antistatic agent, an ultraviolet ray preventing agent, a plasticizer, a lubricant, and the like. In order to improve, corona treatment, low temperature plasma treatment, ion bombardment treatment, chemical treatment, solvent treatment and the like may be performed.

  Although the thickness of the base material layer (1) is not particularly limited, it is practically 3 to 200 μm in view of suitability as a packaging material and workability when other layers are laminated. In this range, a thickness of about 6 to 30 μm is more preferable.

  The inorganic oxide used for the vapor deposition thin film layer (2) is made of aluminum oxide, silicon oxide, tin oxide, magnesium oxide or a mixture thereof, and is transparent and has excellent gas barrier properties such as oxygen and water vapor. Yes. Among these, a vapor-deposited thin film layer made of aluminum oxide, silicon oxide, magnesium oxide or a mixture thereof is preferable because of its excellent oxygen permeability and water vapor permeability. The thickness of the deposited thin film layer is 5 to 300 nm, more preferably 5 to 100 nm. When the film thickness is less than 5 nm, it may be difficult to obtain a uniform film, or the layer thickness may not be sufficient, and may not fully function as a gas barrier material. When the film thickness exceeds 300 nm It is difficult to maintain flexibility in the deposited thin film layer, and if an external stress such as bending or pulling is applied after the film formation, the thin film may be cracked, which is not good.

  The vapor deposition thin film layer (2) can be formed by a normal vacuum vapor deposition method, but other thin film formation methods such as sputtering, ion plating, plasma vapor deposition (CVD), etc. It can also be used. However, considering productivity, the vacuum deposition method is the best at present. As a means for heating the evaporation raw material in the vacuum evaporation apparatus, an electron beam heating method, a resistance heating method, an induction heating method, or the like is preferable. Further, in order to improve the adhesion to the base material layer, it is possible to use a plasma assist method or an ion beam assist method. Furthermore, in order to increase the transparency of the deposited thin film layer, it is possible to carry out reactive deposition in which oxygen gas or the like is blown during deposition.

  The gas barrier coating layer (3) has a two-layer structure of a gas barrier coating layer (3a) and a gas barrier coating layer (3b). The reason why the gas barrier coating layer (3) has a two-layer structure is that, for example, it is very difficult to form a coating layer having a thickness of about 10 μm once by vapor deposition, and the production efficiency is also low. . Therefore, as in the present invention, for example, two layers of uncured flash vapor-deposited coating layers such as monomers are sequentially laminated, and the two flash vapor-deposited coating layers are simultaneously cured to form a gas barrier property of a two-layer structure comprising a cured coating. This is because it is more efficient to obtain a coating layer, and a good coating can be obtained. The gas barrier coating layer (3) having a two-layer structure is formed by laminating two uncured flash vapor deposition coating layers made of acrylic monomers or a mixture of monomers and oligomers on the vapor deposition thin film layer (2) and then ultraviolet rays. Alternatively, an electron beam is irradiated to simultaneously cure the two uncured flash vapor-deposited coating layers to form a gas barrier coating layer (3a) and a gas barrier coating layer (3b) made of a cured coating. Therefore, it can be continuously laminated on the vapor deposition thin film layer (2) in the vacuum film forming apparatus, enabling efficient production and reducing production cost. In addition, the obtained gas barrier coating layer (3a) and gas barrier coating layer (3b) have very strong adhesive strength between the layers, and have two layers, so that they have higher gas barrier properties. Even when stress is applied from the outside, the outer gas barrier coating layer (3b) serves as a protective layer to prevent the gas barrier property from being lowered.

The flash-deposited coating layer refers to an uncured coating layer formed on the surface of an object by dropping a monomer or mixture from a nozzle or the like into a high-temperature evaporation source in a vacuum film forming apparatus and vaporizing it. .

  When the flash vapor-deposited coating layer is cured by irradiating with ultraviolet rays, an acrylic monomer or a mixture of a monomer and an oligomer and a photopolymerization initiator are used. Specific examples of the photopolymerization initiator include benzoin ethers, benzophenones, xanthones, acetophenone derivatives, and the like. The photopolymerization initiator is an acrylic monomer or a mixture of monomers and oligomers. It is used by mixing at a ratio of 01 to 10% by weight, preferably 0.1 to 2% by weight.

  When the flash vapor deposition coating layer is irradiated with an electron beam and cured, it is important to balance the film thickness of the flash vapor deposition coating layer with the energy condition of the electron beam, the processing speed, and static elimination. Care must be taken because excessive energy supply causes charging, and the resulting discharge may impair gas barrier properties.

  The acrylic monomers and oligomers preferably contain at least one of monoacrylate, diacrylate, and triacrylate, and polyester acrylate, polyether acrylate, acrylic acrylate, urethane acrylate, epoxy acrylate, silicone acrylate Highly polymerizable monomers or oligomers such as polyacetal acrylate, polybutadiene acrylate, and melamine acrylate can be appropriately selected and used.

  In addition, the raw material used for the flash vapor deposition coating layer forming the gas barrier coating layer (3a) is at least a monoacrylate having a functional group such as a hydroxyl group, a carboxyl group, an amino group, an epoxy group, or a phenyl group. What contains 1 or more is preferable, and adhesiveness with a vapor deposition thin film layer (2) can be improved more by using these raw materials. The diacrylate is used as a basic component, and the triacrylate is used to improve the degree of crosslinking. However, since these are not good in adhesion to the vapor-deposited thin film layer (2), the functional group is added. Preference is given to using raw materials containing monoacrylates.

  The total film thickness of the gas barrier coating layer (3a) and the gas barrier coating layer (3b) is preferably 0.02 to 20 μm. When the film thickness is less than 0.02 μm, it is difficult to form a uniform coating layer, and when it exceeds 20 μm, the curing rate is lowered and it is difficult to sufficiently cure.

  In addition, when forming a flash-deposited coating layer, the raw acrylic monomer or monomer / oligomer mixture is dropped in a small amount into a high-temperature evaporation source under vacuum, and instantaneously just above the evaporation source. In this case, if the viscosity of the acrylic monomer or the mixture of the monomer and the oligomer is too high, it is difficult to drop it into the evaporation source little by little at a constant speed. It is desirable to set it as s / 25 degreeC or less, More preferably, you may be 100 mPa * s / 25 degreeC or less.

  Furthermore, since the gas barrier laminate film of the present invention is also used in the packaging field of foods, daily necessities, pharmaceuticals, etc., the acrylic monomer or a mixture of monomers and oligomers has a PII (Primary Irritation Index) of 2.0 or less. It is desirable to be. In addition, said PII shows the grade of the skin disorder | damage | failure of a chemical product, and irritation | stimulation is so low that a value is small.

Further, the plasma treatment applied to the surface of the vapor-deposited thin film layer (2) and / or the outermost surface of the gas barrier film layer (3) is performed by the adhesion between the vapor-deposited thin film layer (2) and the gas barrier film layer (3). In addition, the uncured component of the used material is removed to improve the degree of curing, and further, when another layer is laminated on the gas barrier laminate film, the adhesion between both layers is improved. Although there are various plasma processing methods, it is desirable to convert the plasma processing gas into plasma using a DC power source or an RF power source because the processing effect can be exhibited at low cost. Moreover, the gas for plasma treatment is not particularly limited. However, when the outermost surface of the gas barrier coating layer is treated, in order to efficiently remove uncured components, at least hydrogen, oxygen, nitrogen, fluorine, carbon dioxide In order to generate plasma continuously and stably, it is desirable to use a mixed gas including at least one inert gas.

  Further, when the gas barrier laminate film of the present invention is used as a packaging material for foods, the residual acrylic monomer or the like becomes a sanitary problem. Useful to do.

  In the gas barrier laminate film of the present invention, the vapor-deposited thin film layer (2) and the gas barrier coating layer (3) may be further laminated on the other surface of the base material layer (1), or the gas barrier coating layer (3 In addition, a vapor-deposited thin film layer and a gas barrier coating layer may be further laminated on top, and a printing layer may be further laminated on the gas barrier coating layer (3). For example, various pigments, extender pigments, plasticizers, desiccants, stabilizers, etc. are added to conventionally used ink binder resins such as urethane, acrylic, nitrocellulose, rubber and vinyl chloride. Using ink, 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 is used. Door can be. The thickness may be 0.1 μm or more and 2.0 μm or less.

  Further, when a laminated packaging material is prepared using the gas barrier laminate film of the present invention, the gas barrier laminate film of the present invention is used as the outermost film, and the gas barrier coating surface is respectively intermediated with an adhesive. A film layer and a heat seal layer may be sequentially laminated, and the gas barrier laminate film of the present invention is used as an intermediate layer, and an outer film layer is laminated on one surface via an adhesive, and the other surface is laminated. You may make it the structure which laminated | stacked the heat seal layer through the adhesive agent.

  Examples of the intermediate film layer and the outer film layer include a polyester film made of polyethylene terephthalate or polyethylene naphthalate, a polyolefin film made of polyethylene or polypropylene, a polyamide film, a polycarbonate film, a polyacrylonitrile film, and a polyimide film. As the adhesive, a one-component or two-component curable urethane adhesive is used. The heat seal layer is provided to produce a bag-like package, such as polyethylene, polypropylene, ethylene / vinyl acetate copolymer, ethylene / methacrylic acid copolymer, ethylene / methacrylic acid ester copolymer. Resin such as ethylene / acrylic acid copolymer, ethylene / acrylic acid ester copolymer and their cross-linked metal is used, and the thickness is determined according to the purpose, but is generally in the range of 15 to 200 μm. It is. As a method for laminating the heat seal layer, the above resin or resin film is laminated by an melt extrusion extrusion method, a dry lamination method or the like via an adhesive.

  The gas barrier laminate film of the present invention will be further described with specific examples.

A biaxially stretched polyethylene terephthalate film (PET film) having a thickness of 12 μm is used as the base material layer (1). First, metal aluminum is evaporated by an electron beam heating method using a vacuum film forming apparatus, and oxygen is then added thereto. 15n thick on one side of the PET film by introducing gas
m, a vapor deposition thin film layer (2) of aluminum oxide, and a 0.05 μm thick flash vapor deposition coating layer composed of phenyl group-added monoacrylate on the vapor deposition thin film layer (2), diacrylate / triacrylate = 80 A flash vapor deposition coating layer having a thickness of 0.15 μm composed of a mixture of / 20 (% by weight) was sequentially laminated and then irradiated with an electron beam to simultaneously cure the two flash vapor deposition coating layers. 3a) and a gas barrier coating layer (3b) were formed. Subsequently, using a DC power source, a mixed gas of nitrogen / argon = 1/1 was converted into plasma, and the surface of the gas barrier coating layer (3b) was subjected to plasma treatment to produce a gas barrier laminated film of the present invention.

  In Example 1, the gas barrier laminated film of the present invention was prepared in the same manner except that the surface of the gas barrier coating layer (3b) was not subjected to plasma treatment.

  In the following, comparative examples of the present invention will be described.

  A biaxially stretched polyethylene terephthalate film (PET film) with a thickness of 12 μm is used as the base material layer. First, using a vacuum film formation apparatus, metal aluminum is evaporated by an electron beam heating method, and oxygen gas is introduced therein. Then, a 15 nm thick aluminum oxide vapor deposited thin film layer was formed on one side of the PET film, and a 0.05 μm thick flash vapor deposited film layer made of phenyl group-added monoacrylate was laminated on the vapor deposited thin film layer. Thereafter, the flash vapor deposition coating layer is cured by irradiating with an electron beam to form a gas barrier coating layer, and a thickness of 0.15 μm comprising a mixture of diacrylate / triacrylate = 80/20 (weight percentage) is formed thereon. After the flash vapor-deposited coating layer is laminated, the flash vapor-deposited coating layer is cured by irradiating an electron beam to form a gas barrier coating layer. It was. Subsequently, using a DC power source, a mixed gas of nitrogen / argon = 1/1 was converted into plasma, and the outer gas barrier coating layer surface was subjected to plasma treatment to prepare a comparative gas barrier laminate film.

  A comparative gas barrier laminated film was obtained in the same manner as in Example 3 except that the surface of the outer gas barrier coating layer was not plasma-treated.

  An electron beam was irradiated after laminating only a 0.2 μm-thick flash vapor deposition coating layer consisting of phenyl group-added monoacrylate / diacrylate / triacrylate = 30/40/30 (weight% ratio) on the vapor deposition thin film layer. A comparative gas barrier laminate film was prepared in the same manner as in Example 1 except that the flash vapor deposition coating layer was cured to form one gas barrier coating layer.

<Evaluation>
Urethane for back printing on the outer gas barrier coating layer using the gas barrier laminate film of Examples 1-2 of the present invention, the gas barrier laminate film of Comparative Examples 3-5 and the gas barrier laminate film thereof A print film in which a print layer is laminated with a system ink, and further a heat of 50 μm in thickness made of a polypropylene resin through a polyurethane adhesive with a coating amount of 5 g / m ² (dry state) on the print layer of the print film. A sealing film was laminated to prepare a laminated film. While measuring the oxygen permeability of the said gas-barrier laminated | multilayer film single-piece | unit, a printing film, and a laminate film with the measuring method shown below, it measured and evaluated the laminate strength of the laminate film with the measuring method shown below. The results are shown in Table 1.
(1) Measuring method of oxygen permeability Using Modern Control (MOCON OXTRAN 10 / 50A), 25
Measured in an atmosphere of ° C-100% RH.
(2) Method for measuring laminate strength A test piece was prepared by slitting the prepared laminate film to a width of 15 mm, and the laminate strength of the test piece was measured with a Tensilon universal testing machine.

表１に示すように、本発明の実施例１〜２のガスバリア性積層フィルム及びそのガスバリア性積層フィルムを用いた印刷フィルム及びラミネートフィルムはいずれもその酸素透過度は小さく、またラミネートフィルムのラミネート強度も強い。一方、比較用の実施例３〜５のガスバリア性積層フィルムを用いた印刷フィルム及びラミネートフィルムの酸素透過度は積層フィルム単体より大きく劣化しており、ラミネートフィルムのラミネート強度も小さい。

As shown in Table 1, the gas barrier laminate films of Examples 1 and 2 of the present invention and the print films and laminate films using the gas barrier laminate films have low oxygen permeability, and the laminate strength of the laminate films. Is also strong. On the other hand, the oxygen permeability of the printing film and the laminate film using the gas barrier laminate films of Comparative Examples 3 to 5 is greatly deteriorated compared to the laminate film alone, and the laminate film has a low laminate strength.

It is a sectional side view which shows one Embodiment of the gas barrier laminated film of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Base material layer 2 ... Deposition thin film layer 3a, 3b, 3 ... Gas barrier coating layer

Claims (6)

  In a gas barrier laminated film in which a vapor-deposited thin film layer made of an inorganic oxide and two or more gas barrier coating layers are laminated on at least one surface of a base material layer made of a transparent plastic film, the two or more gas barrier coating layers are Two or more uncured flash vapor-deposited coating layers composed of acrylic monomers or a mixture of monomers and oligomers are laminated on the vapor-deposited thin film layer, and then irradiated with ultraviolet rays or electron beams to simultaneously form two or more flash vapor-deposited coating layers. A gas barrier laminate film comprising a cured product.   The gas barrier laminate film according to claim 1, wherein the acrylic monomer or a mixture of the monomer and the oligomer comprises at least one of monoacrylate, diacrylate, and triacrylate.   The gas barrier laminate film according to claim 1 or 2, wherein a viscosity of the acrylic monomer or a mixture of the monomer and the oligomer is 200 mPa · s / 25 ° C or less.   4. The gas barrier laminate film according to claim 1, wherein a total film thickness of the two or more gas barrier coating layers is 0.02 to 20 μm. 5.   The gas barrier laminate film according to any one of claims 1 to 4, wherein the inorganic oxide is silicon oxide, aluminum oxide, magnesium oxide, or a mixture thereof.   6. The gas barrier laminate film according to claim 1, wherein the surface of the deposited thin film layer and / or the outermost surface of the gas barrier coating layer is plasma-treated.

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