JP2006326899A - Gas barrier laminated film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a transparent gas barrier laminated film of which the gas barrier properties are not lowered even if various post-processings such as printing, lamination, etc. are applied. <P>SOLUTION: In the gas barrier laminated film constituted by laminating a vaporized thin film layer composed of an aluminum oxide represented by a formula, AlxOy, and a gas barrier film layer on one side of a transparent base material layer, the ratio of x and y of the aluminum oxide is x:y=2:1-3 and the gas barrier film layer is formed by laminating an uncured flash vapor deposition film layer, which comprises an acrylic monomer containing at least one of monoacrylate, diacrylate and triacrylate or a mixture of the acrylic monomer and an oligomer, on the vaporized thin film layer and irradiating the uncured flash vapor deposition film layer with ultraviolet rays or an electron beam. The viscosity of the monomer or the mixture of the monomer and the oligomer is 200 mPa s/25°C or below. <P>COPYRIGHT: (C)2007,JPO&INPIT

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

  However, the proposed vapor deposition film has drawbacks such as deterioration of gas barrier properties such as oxygen and water vapor when various post-processing such as printing, laminating, and bag making are performed.

  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 in which a vapor-deposited thin film layer of aluminum oxide represented by the general formula AlxOy and a gas barrier coating layer are laminated on at least one side of a base material layer made of a transparent plastic film. In the film, the ratio of x to y of the aluminum oxide is x: y = 2: 1 to 3, and the gas barrier coating layer is an uncured flash vapor deposition coating composed of an acrylic monomer or a mixture of a monomer and an oligomer. A gas barrier laminate film comprising a layer laminated on the deposited thin film layer and then cured by irradiation with ultraviolet rays or electron beams.

  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 characterized in that, in the invention according to any one of claims 1 to 3, the film thickness of the gas barrier coating layer is 0.02 to 20 μm. It is a gas barrier laminate film.

  The invention according to claim 5 of the present invention is the invention according to any one of claims 1 to 4, wherein the surface of the deposited thin film layer and / or the outer surface of the gas barrier coating layer is plasma-treated. This is a gas barrier laminate film.

  The gas barrier laminate film of the present invention is a gas barrier laminate film in which a vapor-deposited thin film layer of aluminum oxide represented by the general formula AlxOy and a gas barrier coat layer are laminated on at least one surface of a base material layer made of a transparent plastic film. The ratio of x to y of the aluminum oxide is x: y = 2: 1 to 3, and the gas barrier coating layer is an uncured flash vapor deposition coating layer made of an acrylic monomer or a mixture of a monomer and an oligomer. Since it is laminated on the deposited thin film layer and then cured by irradiation with ultraviolet rays or electron beams, it is transparent and has excellent gas barrier properties. Sex does not decrease. 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 lower, it has good adhesion to the vapor deposited thin film layer, and the efficiency in forming the flash vapor deposited film layer is good. Furthermore, the surface of the vapor deposited thin film layer and the outer surface of the gas barrier film layer are plasma treated. As a result, 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 are improved, and uncured components may remain on the outer 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 sectional view showing an embodiment of a gas barrier laminate film of the present invention, in which a base material layer (1), a deposited thin film layer (2), and a gas barrier coating layer (3) are laminated in order in the thickness direction. Has been.

  The base material layer (1) is made of a plastic film. Examples of the plastic film include polyester films made of polyethylene terephthalate (PET), polyethylene naphthalate (PEN), and polyolefins made of polyethylene, polypropylene, and the like. Biodegradable plastic films such as polyethylene films, polystyrene films, polyamide films, polyvinyl chloride films, polycarbonate films, polyacrylonitrile films, polyimide films, polylactic acid films, and the like 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 substrate layer (1) may be a film containing various additives such as an antistatic agent, an ultraviolet ray preventing agent, a plasticizer, and a lubricant, and the surface on which the other layer is laminated has good adhesion. Therefore, 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 vapor-deposited thin film layer (2) is made of aluminum oxide represented by the general formula AlxOy, and the ratio of x to y is x: y = 2: 1 to 1-3. When the value of y exceeds 3, an acrylic monomer or a mixture of monomers and oligomers of a gas barrier coating layer (3) described later enters the vapor-deposited thin film layer (2) and is inherently expressed in water vapor. When the barrier property cannot be expressed and the value of y is 3, the acrylic monomer or the mixture of the monomer and the oligomer starts to be prevented from entering the vapor-deposited thin film layer (2), and the value of y is smaller than 3. As it becomes, it becomes difficult for the acrylic monomer or the mixture of the monomer and the oligomer to penetrate into the deposited thin film layer (2), and the water vapor barrier property of the deposited thin film layer (2) is improved. However, on the contrary, the smaller the value of y, the worse the transparency of the deposited thin film of aluminum oxide, and when the value of y is less than 1, the transparency can hardly be expected. Therefore, the ratio of x to y in the general formula AlxOy is preferably x: y = 2: 1 to 3, and it is necessary to control the value of y in accordance with the required degree of transparency. By controlling appropriately, it is transparent and excellent gas barrier properties such as oxygen and water vapor can be obtained.

  As a method for forming the vapor-deposited thin film layer (2), a generally used vacuum vapor deposition method is most excellent. As a means for heating the evaporation source material in the vacuum film forming apparatus, an electron beam heating method, a resistance heating method, an induction heating method, or the like is preferable. Moreover, in order to improve adhesiveness with a base material layer (1), it is also 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 thickness of the deposited thin film layer (2) 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 be able to 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 gas barrier coating layer (3) is formed by laminating an acrylic monomer or a mixture of a monomer and an oligomer on the vapor deposition thin film layer (2) by flash vapor deposition, and then irradiating it with ultraviolet rays or electron beams and curing it. . For example, an uncured flash vapor-deposited coating layer composed of an acrylic monomer or a mixture of monomers and oligomers is laminated on the vapor-deposited thin film layer (2), and then irradiated with ultraviolet rays or electron beams to form an uncured layer. The flash vapor deposition coating layer is cured to form a gas barrier coating layer (3) comprising a cured coating. Therefore, it is possible to continuously laminate in a vacuum film forming apparatus, and the aluminum oxide vapor-deposited thin film layer (2) and the gas barrier coating layer (3) are continuously laminated in a vacuum as in the present invention. Therefore, efficient production is possible, and production costs can be reduced. The gas barrier coating layer (3) serves as a protective layer when stress is applied from the outside, and prevents the gas barrier property from being lowered.

  The flash-deposited coating layer is 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 evaporating it. To tell.

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

  The raw material used for the flash vapor deposition coating layer for forming the gas barrier coating layer (3) 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. There are various types of monoacrylates, diacrylates, and triacrylates described above, and although there is no particular limitation, the adhesion between the aluminum oxide vapor-deposited thin film layer (2) and the gas barrier coating layer (3) is good. In order to efficiently form a flash-deposited coating layer and to further improve hygiene, for example, propylene glycol monophenyl ether acrylate as monoacrylate, propoxylated neopentyl glycol diacrylate as diacrylate, and ethoxy as triacrylate Trimethylolpropane triacrylate is preferably used and blended at a ratio of monoacrylate / diacrylate / triacrylate = 10/70/20 (% by weight).

  The thickness of the gas barrier coating layer (3) is preferably 0.02 to 20 μm. If the thickness is less than 0.02 μm, it is difficult to form a uniform coating layer, and if it exceeds 20 μm, the curing rate decreases and it is difficult to sufficiently cure.

  In addition, when forming a flash-deposited coating layer, the acrylic monomer or monomer / oligomer mixture, which is the raw material, is dropped in a small amount into a high-temperature evaporation source under vacuum, and instantly evaporated immediately 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, so that the viscosity is 200 mPa · s / 25. It is desirable that the temperature is not higher than 100 ° C., more preferably not higher than 100 mPa · s / 25 ° C.

  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.

The plasma treatment applied to the surface of the vapor-deposited thin film layer (2) and / or the outer surface of the gas barrier film layer (3) can improve the adhesion between the vapor-deposited thin film layer (2) and the gas barrier film layer (3). In addition to the improvement, the uncured component of the used material is removed to improve the degree of curing, and when another layer is laminated on the gas barrier laminate film, the adhesion between the two layers is improved.
There are various plasma processing methods, but the plasma processing gas is not particularly limited by using a DC power source or an RF power source. However, when the outermost surface of the gas barrier coating layer is processed, the plasma processing gas is not limited. Mixing containing at least one of hydrogen, oxygen, nitrogen, fluorine, carbon dioxide and at least one inert gas in order to generate plasma continuously and stably in order to efficiently remove curing components It is desirable to use 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, a vapor-deposited thin film layer (2) of aluminum oxide and a gas barrier coating layer (3) may be further laminated on the other surface of the base material layer (1). An aluminum oxide vapor-deposited thin film layer (2) and a gas barrier coating layer (3) may be further laminated on the layer (3), and a printing layer is further laminated on the gas barrier coating layer (3). In the case of laminating a printing layer, various pigments, extender raw materials and plasticizers may be used in conventionally used ink binder resins such as urethane, acrylic, nitrocellulose, rubber and vinyl chloride. Ink with added desiccant, stabilizer, etc., well-known printing methods such as offset printing method, gravure printing method, silk screen printing method, roll coating, knife etching, etc. Coating, known coating methods such as gravure coating can be used. 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 polyurethane 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 adhesive extrusion method, a dry lamination method, or the like.

  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. Gas was introduced to form a 15 nm thick aluminum oxide vapor-deposited thin film layer (2) having a general formula AlxOy of 2.0 and y of 2.4 on one side of the PET film, and continuously Thickness formed of a mixture having a blending ratio of propylene glycol monophenyl ether acrylate / propoxylated neopentyl glycol diacrylate / ethoxylated trimethylolpropane triacrylate = 10/70/20 (% by weight) on the deposited thin film layer (2). After sequentially depositing 0.2μm flash deposited coating layer, the flash deposited coating layer is cured by irradiation with electron beam. Thus, a gas barrier coating layer (3) was formed. Subsequently, a mixed gas of nitrogen / argon = 1/1 was converted into plasma using a DC power source, and the surface of the gas barrier coating layer (3) was subjected to plasma treatment to produce a gas barrier laminated film of the present invention.

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

  The comparative examples of the present invention will be described below.

  A comparative gas barrier laminated film was prepared in the same manner as in Example 1 except that an aluminum oxide vapor-deposited thin film layer having a general formula AlxOy of 2.0 and y of 3.4 was laminated.

  A comparative gas barrier laminated film was prepared in the same manner as in Example 1 except that an aluminum oxide vapor-deposited thin film layer having a general formula of AlxOy of 2.0 and y of 0.8 was laminated.

  A comparative gas barrier laminated film was prepared in the same manner as in Example 1 except that an aluminum metal vapor-deposited thin film layer having a thickness of 15 nm was laminated.

<Evaluation>
Intermediate components of the gas barrier laminate films of the present invention of Examples 1 and 2 and comparative gas barrier laminate films of Examples 3 to 5, i.e., components obtained by laminating a vapor deposition thin film layer of aluminum oxide on a 12 μm PET film The light transmittance of was measured by the following measuring method. In addition, using the gas barrier laminate film of the present invention of Examples 1 and 2 and the gas barrier laminate film for comparison of Examples 3 to 5, a printing layer with a urethane ink for back printing on the outer gas barrier coating layer And a heat-seal layer having a thickness of 50 μm made of polypropylene resin is laminated on the print layer of the print film through a polyurethane adhesive having a coating amount of 5 g / m ² (dry state). A laminate film was prepared. The water vapor transmission rate of the gas barrier laminate film, the printed film, and the laminate film having the final structure thus prepared was measured and evaluated by the following measurement method. The results are shown in Table 1.
(1) Light transmittance: The transmittance of light with a wavelength of 366 nm was measured using a spectrophotometer (UV-3100, manufactured by Shimadzu Corporation).
(2) Measuring method of water vapor transmission rate It measured in 40 degreeC-90% RH atmosphere using the modern control company make (MOCON PERMATRAN-W 3/31).

表１に示すように、実施例１〜２の本発明のガスバリア性積層フィルムの中間構成品、即ち、１２μｍのＰＥＴフィルムに蒸着薄膜層を積層した構成品の光線透過率は６０％と良好であり、さらに最終構成のガスバリア性積層フィルムの水蒸気透過率も小さく、さらに印刷フィルム、ラミネートフィルムの水蒸気透過率も劣化を受けず、小さく優れていた。一方、実施例３の比較用のガスバリア性積層フィルムの中間構成品、即ち、１２μｍのＰＥＴフィルムに蒸着薄膜層を積層した構成品の光線透過率は８８％と優れていたが、最終構成のガスバリア性積層フィルム及び印刷フィルム、ラミネートフィルムの水蒸気透過率は大きく、不良であり、実施例４〜５の比較用のガスバリア性積層フィルムの中間構成
品、即ち、１２μｍのＰＥＴフィルムに蒸着薄膜層を積層した構成品の光線透過率はそれぞれ、３０％と２０％で透明性が不良であった。

As shown in Table 1, the light transmittance of the intermediate component of the gas barrier laminate film of the present invention of Examples 1-2, that is, a component obtained by laminating a vapor-deposited thin film layer on a 12 μm PET film is as good as 60%. Furthermore, the water vapor transmission rate of the gas barrier laminate film of the final configuration was small, and the water vapor transmission rate of the printing film and laminate film was not deteriorated and was excellent. On the other hand, the intermediate component of the gas barrier laminate film for comparison of Example 3, that is, the component obtained by laminating the deposited thin film layer on the 12 μm PET film had an excellent light transmittance of 88%. Laminate film, printed film, and laminate film have large and poor water vapor transmission rate, and a vapor-deposited thin film layer is laminated on an intermediate component of a gas barrier laminate film for comparison in Examples 4 to 5, that is, a 12 μm PET film. The components had a light transmittance of 30% and 20%, respectively, and the transparency was poor.

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 3 ... Gas barrier film layer

Claims (5)

  In a gas barrier laminated film in which a vapor-deposited thin film layer of aluminum oxide represented by the general formula AlxOy and a gas barrier coating layer are laminated on at least one surface of a base material layer made of a transparent plastic film, x and y of the aluminum oxide After the ratio of x: y = 2: 1 to 3 and the gas barrier coating layer is laminated on the deposited thin film layer with an uncured flash deposited coating layer made of an acrylic monomer or a mixture of monomers and oligomers A gas barrier laminate film comprising a film cured by irradiation with ultraviolet rays or electron beams.   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 the acrylic monomer or a mixture of the monomer and the oligomer has a viscosity of 200 mPa · s / 25 ° C or less.   The gas barrier laminate film according to any one of claims 1 to 3, wherein a film thickness of the gas barrier coating layer is 0.02 to 20 µm.   The gas barrier laminate film according to any one of claims 1 to 4, wherein a surface of the vapor-deposited thin film layer and / or an outer surface of the gas barrier coating layer is plasma-treated.

Images