JPH07205363A - Gas barrier laminate - Google Patents

Abstract

PURPOSE:To improve the barrier properties to oxygen and steam of laminate used for packaging material by a method wherein the adhesion between the film deposit of metal or metal compound as structural layer and its adjacent layer is reformed. CONSTITUTION:Organic silicon compound 120 layer represented by a chemical formula R-Si-(OR')3, in which R represents organic functional group and R' represents hydrolyzable groups, is formed at least on one side of synthetic resin film. Film deposit 130 of metal or metal compound is formed on the plasma activation-treated surface of the organic silicon compound 120 layer. Further, on the formed film deposit 130 surface, hot gluing resin layer 150 is provided through adhesive 140 layer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas barrier laminate for a packaging material having a good barrier property against oxygen, water vapor and the like.

[0002]

2. Description of the Related Art Conventionally, gas barrier synthetic resin films include polyvinyl alcohol film, polyacrylonitrile film, ethylene / vinyl alcohol copolymer resin film for oxygen, and polypropylene film for water vapor. Although there are polyethylene films, etc., these synthetic resin films alone do not have both oxygen and water vapor barrier properties, so films of other types with different properties were laminated and each property was utilized. It was used as a laminated film in packaging materials. However, these laminated films are sometimes affected by the temperature and humidity in the storage or use environment and may not exhibit sufficient barrier performance. On the other hand, as a synthetic resin film having barrier properties against both oxygen and water vapor, there are polyvinylidene chloride films, coated films obtained by coating polyvinylidene chloride on polyester films, polypropylene films, nylon films, etc., but these films are However, there is an environmental problem because toxic gas is generated when incinerated after use. Conventionally, in the case of a packaging material that requires a high degree of barrier property, a synthetic resin film to which an aluminum foil is attached has been used. However, although the packaging material using such a metal foil has excellent barrier properties against oxygen and water vapor,
As waste after use, residual slag remains when incinerated,
It was difficult to reuse, and it was not preferable in terms of environmental hygiene. Therefore, as a means for improving environmental hygiene problems, a synthetic resin film on which a metal such as aluminum, aluminum oxide or silicon oxide or a metal oxide is vapor-deposited has been used.

[0003]

However, in the above-mentioned metal and metal oxide vapor-deposited thin film, since the synthetic resin film of the base material is an organic compound, it is an inorganic compound.
Its mechanical, chemical and thermal properties are very different. Evaporated films are combinations of different properties. Therefore, when mechanical or thermal stress is applied to the vapor-deposited film, the vapor-deposited thin film may be distorted due to the difference in strength to cause cracks or pinholes, or the chemical bond state may be different. Therefore, the vapor-deposited thin film causes delamination from the base material film, and further, the vapor-deposited thin film may be distorted or have poor adhesion depending on the content,
The barrier performance of the vapor-deposited film was sometimes significantly impaired.

Therefore, many attempts have been made in the past to improve the adhesion between the synthetic resin film as the base material and the vapor-deposited thin film. For example, a method has been used in which the surface of a polyester film is subjected to corona discharge treatment, ultraviolet irradiation treatment, plasma treatment or flame treatment to activate the surface, and then a metal or a metal oxide is deposited. However, these activation methods of the film surface can be expected to improve the adhesiveness by enhancing the secondary bonding force due to wetting with respect to the vapor-deposited thin film, but the activation ability thereof decreases with time, or the adhesion which is not always satisfactory. I couldn't say enough because I couldn't get the strength.

Further, as another method for improving the adhesion between the polyester film and the vapor-deposited thin film of metal or metal oxide, a surface treatment method using a chemical such as acid or alkali, polyester film and other components such as acid component or There are co-extruded polyester film co-polymerized with glycol component etc. or co-extruded multilayer polyester film co-extruded with other resin at the time of forming the polyester film, but none of them have sufficiently satisfactory adhesion. .

[0006] Further, on the surface of the synthetic resin film of the base material, ethyleneimine-based, off-line or in-line,
Although there is a method of applying an amine-based, epoxy-based, urethane-based or polyester-based anchor coating agent, the coating surface has improved adhesion to the vapor-deposited thin film of metal or metal oxide, but the barrier property is anchor. It was lower than that of the vapor-deposited synthetic resin film on which no coating agent was applied. This is because the anchor coating layer has poor thermal dimensional stability, so that the vapor-deposited thin film is mechanically stressed when the vapor-deposited polyester film is thermally loaded, and as a result, cracks and pinholes are generated in the vapor-deposited thin film, resulting in a barrier. This is because the sex is reduced.

The present invention improves the adhesion between the synthetic resin film substrate and the vapor-deposited thin film, and solves the problem that the barrier property is impaired by the occurrence of cracks or pinholes in the vapor-deposited thin film. A gas barrier laminate for use as a packaging material having a good barrier property against water vapor and the like.

[0008]

The first invention, as shown in FIG. 1, has a chemical formula of R-Si- (OR ') ₃ (R is an organic functional group) on at least one surface of the synthetic resin film (110). A group, R'is a hydrolyzable group) to form an organosilicon compound layer (120), and a plasma-activated surface (121) is provided with a vapor-deposited thin film layer (130) of a metal or a metal compound. A gas barrier laminate (100) characterized by being formed.

A second invention is the organic battery described in the first invention.
The organic functional group (R) of the iodine compound layer is -CH = C
H₂, -CH₂-CH₂-CH₂-NH₂, -CH₂−
NH₂, -CH₂-NHCONH₂, -CH₂-NH-
CH₂-CH₂-NH₂,-(C ₂H₂O)-,-CH
₂-O-CH₂-(C₃H₃O) is a hydrolyzable group
(R ') is -Cl, -CH₃, -CH₂-CH₃,-
CH₂-O-CH₃Gas barrier characterized by
It is a laminated body.

As shown in FIG. 2, the third aspect of the present invention includes an adhesive layer (140) on the vapor-deposited thin film layer surface (130) of the metal or metal compound according to the first or second aspect of the invention. The gas barrier laminate (200) is characterized in that a heat adhesive resin layer (150) is provided.

Examples of the synthetic resin film described above include polyolefin films such as polyethylene and polypropylene, polyethylene terephthalate and polyethylene-2,
Polyester film such as 4-naphthalate, polyamide film such as nylon 6 or nylon 12, polyvinyl chloride film, polyvinyl alcohol film, aromatic polyamide film, polyamideimide film,
Polyetherimide film, polysulfone film, polyethersulfone film, polyetheretherketone, polyarylate film, polyphenylene sulfide film, polyphenylene oxide film, tetrafluoroethylene film, monofluorotrifluoroethylene film, fluorinated ethylene propylene copolymer An example is a united film. If necessary, these biaxially stretched synthetic resin films are used. Incidentally, these synthetic resin films may be added with usual additives such as an antistatic agent, an ultraviolet absorber, a plasticizer, a lubricant and a coloring agent, and also a surface for forming an organosilicon compound. Surface activation treatment such as corona discharge treatment, plasma treatment, glow discharge treatment, reverse sputtering treatment or surface roughening treatment may be performed. The thickness of these synthetic resin films is not particularly limited, but is preferably in the range of 2 to 400 μm in consideration of workability in the vapor deposition process.

A method of forming an organosilicon compound layer
Is an in-line coating method when manufacturing a synthetic resin film.
Even if it is clothed, it is a separate process from the manufacturing of synthetic resin film
It may be applied by a line method or either. And the book
The organosilicon compound in the invention is R-Si- (O
R ')₃(R is an organic functional group, R'is a hydrolyzable group)
It is represented by a chemical formula and has an organic functional group (R)
Is -CH = CH₂, -CH ₂-CH₂-CH₂-NH
₂, -CH₂-NH₂, -CH₂-NHCONH₂,-
CH₂-NH-CH₂-CH₂-NH₂,-(C₂H₂
O)-,-CH₂-O-CH₂-(C₃H₃O) etc.
Yes, an epoxy group, an amino group, a urea group and the like are preferable,
Further, the hydrolyzable group (R ') is -Cl, -CH.₃,-
CH₂-CH₃, -CH₂-O-CH₃And so on. Na
There is no particular limitation on the thickness of the organosilicon compound layer.
However, considering the workability and thermal dimensional stability, it is 0.05
Is in the range of 10 to 10 μm, preferably 0.1 to 3 μm
Is.

As a method for plasma activation treatment of the surface of the organic silicon compound layer on which the vapor-deposited thin film is formed, glow discharge treatment, high frequency plasma treatment, microwave plasma treatment or the like can be used. As the gas used, an oxygen-containing mixed gas is used, and there is no limitation as long as the mixing ratio of oxygen is in the range of 1 to 100%. The gas mixed with oxygen is not particularly limited as long as it is a stable gas such as nitrogen, argon or carbon dioxide. In addition, the pressure of the processing portion of the plasma processing is 8 × 10 ⁻⁵ to 8 × 10 ⁻¹ torr.
And preferably 8 × 10 ⁻⁴ to 8 × 10 ⁻³ Torr. The plasma treatment energy applied to the treated surface may be in the range of 1 to 50,000 joules, but is preferably in the range of 10 to 10,000 joules. This is because the treated surface is not sufficiently activated at 1 joule or less, and the molecules on the treated surface are destroyed at 50,000 joules or more, and a vapor-deposited thin film having a uniform thickness cannot be obtained.

Method for forming thin film of metal or metal compound of the present invention
Methods include vacuum deposition, ion plating, sputter phosphorus
You can use a vapor deposition method such as
Rating is preferred. Resistance heating is used as the heating method.
Heat, EB heating, high frequency induction heating, etc. can be used
It The vapor deposition materials are aluminum (Al), silicon (S
i), titanium (Ti), zinc (Zn), zirconium
(Zr), magnesium (Mg), tin (Sn), copper
(Cu) and metals such as iron (Fe) and these metals
Oxides, nitrides, sulfides, fluorides, etc., such as oxidation
Aluminum (Al₂O ₃), Silicon oxide (SiO),
Titanium oxide (TiO₂), Zirconium oxide (Zr
O₂), Magnesium oxide (MgO), tin oxide (Sn
O₂), Zinc sulfide (ZnS), magnesium fluoride (M
gF₂) Or the like can be used. And before deposition
The degree of vacuum in the vapor deposition equipment is 2 × 10^-6~ 8 × 10^-3Thor
It may be in the range of (torr), but is preferably 8 × 10.^-6
~ 8 × 10^-FiveAfter evacuation to torr, vapor deposition
To do. Also, a vapor-deposited thin film of the formed metal or metal compound.
The layer is a layer having a barrier property against oxygen, water vapor, etc.
However, the barrier characteristics are the material and film thickness of the formed material.
It depends on the situation. In particular, metallic aluminum, silicon oxide
Barrier features such as vapor-deposited thin films of silicon and aluminum oxide
Shows sex. Thickness of the deposited thin film layer of this metal or metal compound
May be in the range of 50 to 5,000Å, but preferably,
The range of 300 to 1,500Å is good. It has a thickness of 5
If it is less than 0Å, it is difficult to control the uniform film thickness and
It is easy to cause variations in sex, and more than 5,000Å
In the case of, it is easy for cracks and pinholes to occur in the evaporated thin film layer.
This is because the barrier properties are impaired. Vapor deposition formed
The thin film layer is not limited to a single component single layer, but a vapor-deposited thin film of a mixture.
It may be a layer or a multilayer vapor-deposited thin film layer.

The heat-adhesive resin layer in the present invention is a synthetic resin layer that is easily heat-fused by heating and pressurizing. Examples of the synthetic resin include polyolefin such as polyethylene, polypropylene and ethylene-propylene copolymer, polyester,
Examples include polyamides, ionomers, ethylene vinyl acetate copolymers, acrylic resins such as acrylic acid esters and methacrylic acid esters, polyvinyl acetals, phenolic resins, modified epoxy resins, and copolymers and mixtures thereof, but not necessarily these. It is not limited to. Among these resins, polyolefin, polyester, polyamide, ethylene vinyl acetate copolymer and the like are preferable. The thickness of the heat-adhesive resin layer varies depending on the application, but is in the range of 1 to 200 μm, preferably 10 to 100 μm. As a laminating method for forming the heat-adhesive resin layer, a general laminating method such as a dry laminating method, a solventless laminating method or an extrusion laminating method can be used. The heat fusion temperature of the heat-adhesive resin layer is 200 ° C. or lower in consideration of the heat resistance of the alkoxide coating layer,
180 ° C is preferred.

[0016]

The function of the organosilicon compound layer formed on the synthetic resin film in the present invention is that the organic functional group of the organosilicon compound has a strong bonding force with the synthetic resin of the synthetic resin film, so that the adhesiveness with the synthetic resin film is high. And the hydrolyzable group of the organosilicon compound is hydrolyzed to give a hydroxyl group (-
OH) to form an active Si—OH bond with the metal element (M), and the hydroxyl group reacts with the metal element and —O—M—O—.
In order to form a strong bond between the organic silicon compound layer and the metal or metal compound vapor-deposited thin film formed by vapor deposition on the organic silicon compound layer, the organic silicon compound layer has good adhesion.

The metal element (M) formed on the surface of the organosilicon compound layer and the active Si-OH bond may be insufficient depending on the coating conditions. When the plasma activation treatment is performed on the surface of the organosilicon compound layer, Si—OH bonds are uniformly generated on the surface of the organosilicon compound layer, so that the adhesion between the vapor-deposited thin film of the metal or the metal compound and the organosilicon compound layer is stabilized. .

[0018]

【Example】

<Example 1> First, an aqueous solution of N- (β-aminoethyl) -γ-aminopropyltrimethoxysilane (organosilicon compound) having a solid content of 2 wt% was formed on one surface of a biaxially stretched polyethylene terephthalate film having a thickness of 12 μm. Was applied by a gravure coating method and dried to prepare a biaxially stretched polyethylene terephthalate film having an organosilicon compound layer formed on one surface. The winding speed is 40
m / min, the drying condition is 90 to 100 ° C., and the coating amount is
It was 0.15 g / m ² .

Next, the biaxially stretched polyethylene terephthalate film having the organosilicon compound layer formed on one surface was loaded into a winding type EB heating vacuum device, and the vacuum degree was set to 1.5 × 10 ^-5 Torr. After that, oxygen plasma treatment was performed, and silicon oxide was vapor-deposited on the treated surface to produce a gas barrier laminate according to this example. The oxygen plasma treatment conditions at that time were as follows: gas used was 99.9% oxygen, flow rate was 600 sccm, plasma treatment was glow discharge treatment, supply power was 250 W, winding speed was 1.5 m / sec, pressure was 5 × 10 ^{−. It is 3} mbar, and the deposition conditions of silicon oxide are 99.9% silicon oxide and EB-Powe.
The r was 30 kV-0.5 A, the vapor deposition film thickness was 1,000 Å, and the pressure was 2 × 10 ⁻³ mbar.

Further, an unstretched polypropylene film (thermoadhesive resin) having a thickness of 30 μm was attached to the silicon oxide vapor-deposited thin film surface of the produced gas barrier laminate by a dry laminating method to obtain the gas barrier property of Example 1. A laminated body was produced.

<Example 2> The gas barrier property of Example 2 prepared in the same manner as in Example 1 except that an aqueous solution of γ-aminopropyltriethoxysilane having a solid content of 2 wt% was used as the aqueous solution of the organosilicon compound. A laminated body was produced.

<Example 3> A gas barrier laminate of Example 3 was prepared in the same manner as in Example 1 except that the vapor deposition material was aluminum oxide and EB-Power was 30 kV-0.75A. .

<Example 4> A gas barrier laminate of Example 4 was prepared in the same manner as in Example 1 except that the vapor deposition material was magnesium oxide and EB-Power was 30 kV-1.5 A. .

<Embodiment 5> The vapor deposition material is aluminum and E
Except that B-Power did it at 30kV-2.0A.
A gas barrier laminate of Example 5 was prepared in the same manner as in Example 1.

Comparative Example 1 A gas barrier laminate of Comparative Example 1 was prepared in the same manner as in Example 1, except that a urethane resin solution was used instead of the organic silicon compound aqueous solution.

Comparative Example 2 A gas barrier laminate of Comparative Example 2 was prepared in the same manner as in Example 1 except that a nitrocellulose solution was used instead of the organic silicon compound aqueous solution.

Comparative Example 3 A gas barrier laminate of Comparative Example 3 prepared in the same manner as in Example 1 except that a vinyl acetate-vinyl chloride copolymer solution was used instead of the organic silicon compound aqueous solution. The body was made.

Comparative Example 4 Using an EB heating vacuum apparatus, aluminum was vapor-deposited directly on one surface of a biaxially stretched polyethylene terephthalate film having a thickness of 12 μm, and the aluminum vapor-deposited thin film surface was subjected to the same procedure as in Example 1. An unstretched polypropylene film (thermoadhesive resin) having a thickness of 30 μm was laminated to prepare a gas barrier laminate of Comparative Example 5.

<Evaluation> Five kinds of gas barrier laminates of Example 1, Example 2, Example 3, Example 4 and Example 5 produced, and Comparative Example 1, Comparative Example 2, Comparative Example 3 and Comparative Example 4
In order to compare and evaluate the four types of gas barrier laminates of
The oxygen transmission rate and moisture vapor transmission rate showing the barrier property of each gas barrier laminate and the peel strength showing the adhesion between the vapor-deposited thin film layer and the adjacent layer were measured, and the results are shown in Table 1. The measurement conditions are: oxygen transmission rate: MOCON method (MOCON-OXTR
AN-10 / 50A), setting 25 ℃ -100% RH Permeability: Mocon method (MOCON-PARMATRAN-W6), setting 40 ℃ -90% R
H peel strength: Tensilon tensile tester, sample 15mm
The width was 90 °, the peeling angle was 90 °, and the peeling speed was 300 mm / min.

[0030]

[Table 1]

As shown in Table 1, in Example 1, Example 2, Example 3, Example 4 and Example 5, peeling showing the gas barrier property against oxygen and water vapor and the adhesion between the vapor-deposited thin film layer and the adjacent layer. The strength was good. Comparative Example 1,
In Comparative Examples 2 and 3, the adhesion of the vapor-deposited thin film layer was good, but the gas barrier property was poor. Further, in Comparative Example 4, the gas barrier property was good, but the adhesion of the deposited thin film layer was poor.

[0032]

According to the present invention, an organosilicon compound layer is formed between a synthetic resin film substrate and a vapor-deposited thin film layer, and
Since the entire surface of the organic silicon compound layer is plasma-activated, the adhesion of the vapor-deposited thin film to the film substrate and the flexibility against external loads are improved, and the occurrence of cracks and pinholes in the vapor-deposited thin film can be prevented. Provided is a gas barrier laminate of a packaging material having a good barrier property against oxygen and water vapor.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a gas barrier laminate according to an example of the present invention.

FIG. 2 is a cross-sectional view of a gas barrier laminate according to another example of the present invention.

[Explanation of symbols]

 100, 200 ... Gas barrier laminate 110 ... Synthetic resin film 120 ... Organosilicon compound 121 ... Plasma activated surface 130 ... Evaporated thin film 140 ... Adhesive agent 150 ... Thermal adhesive resin layer

Claims (3)

[Claims] 1. A synthetic resin film having a chemical formula of R—Si— (OR ′) ₃ (R is an organic functional group, on at least one side thereof,
R'is a hydrolyzable group), and an organic silicon compound layer is formed, and a vapor-deposited thin film layer of a metal or a metal compound is formed on the plasma-activated surface of the gas barrier laminate. . 2. The presence of the organosilicon compound layer according to claim 1.
The functional group (R) is -CH = CH ₂, -CH₂-CH
₂-CH₂-NH₂, -CH₂-NH₂, -CH₂-N
HCONH₂, -CH₂-NH-CH₂-CH₂-NH
₂,-(C₂H₂O)-,-CH₂-O-CH₂-(C
₃H₃O), the hydrolyzable group (R ′) is —Cl, —C
H₃, -CH₂-CH₃, -CH₂-O-CH₃Is
A gas barrier laminate having the above feature. 3. A gas barrier laminate comprising a vapor-deposited thin film layer of the metal or the metal compound according to claim 1 or 2, wherein a thermoadhesive resin layer is provided via an adhesive layer.