JP3271418B2 - Gas barrier film and gas barrier film for retort - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used as a packaging material or a gas barrier material which is required to be airtight for foods, medicines, electronic parts, etc., which are excellent in gas barrier properties, boil resistance, retort resistance and gelbo properties. The present invention relates to a gas barrier film having excellent properties.

[0002]

2. Description of the Related Art Films having excellent gas barrier properties include those obtained by laminating aluminum on a plastic film and those coated with vinylidene chloride or ethylene vinyl alcohol copolymer. Also,
As a material using an inorganic thin film, a material obtained by laminating a silicon oxide, an aluminum oxide thin film, or the like is known.

[0003]

However, such a conventional gas barrier film has the following problems. The aluminum laminate is excellent in economical efficiency and gas barrier properties, but is opaque, so that the contents at the time of packaging cannot be seen, and cannot be used in a microwave oven because it does not transmit microwaves. Those coated with vinylidene chloride or ethylene vinyl alcohol copolymer do not have sufficient gas barrier properties against water vapor, oxygen, etc., and the decrease is remarkable especially at high temperature treatment. In addition, with respect to vinylidene chloride, there is generation of chlorine gas at the time of incineration, and there is also a concern about the influence on the global environment.

On the other hand, Japanese Patent Publication No. Sho 51-48511 discloses a gas barrier film which can be used in a microwave oven and whose contents can be seen in a synthetic resin body.
A gas barrier film on which _y (for example, SiO ₂ ) is deposited has been proposed, but SiOx (x
= 1.3 to 1.8) has a slightly brown color, which is insufficient as a transparent gas barrier film.

Japanese Patent Application Laid-Open No. Sho 62-101428 discloses a device mainly composed of aluminum oxide.
Oxygen barrier properties are insufficient, and there is also a problem of bending resistance.
Further, JP-A-2-194944, boiling resistance, as a gas barrier film having a retort resistance, _Al 2 O
_{Although a 3} · SiO ₂ -based material has been proposed, Al ₂ O ₃
And SiO ₂ are laminated, and the device becomes large-scale. Also, the gas barrier properties and flex resistance of this thin film-based gas barrier film are still insufficient.

Japanese Patent Application Laid-Open No. Hei 4-226343 proposes a polymer film having a barrier layer in which silicon dioxide is doped with various metals as a barrier material for packaging. However, the polymer film is colored with an increase in the metal doping amount. It tends to be insufficient as a transparent gas barrier film.

Therefore, the present applicant has disclosed in Japanese Patent Application Laid-Open No. Hei 5-17903.
No. ₃ proposed a transparent gas barrier film using an Al ₂ O ₃ .SiO ₂ based thin film and having good bending resistance. However, when this gas barrier film is subjected to post-processes such as lamination and printing, there is no problem under normal conditions, but under severe conditions, there is a problem that gas barrier properties are slightly deteriorated.

The present inventors have studied in detail the flexibility, suitability for the post-process, and the oxidation state of Al and Si of the gas barrier thin film, and have reached the present invention.

It is an object of the present invention to provide a gas barrier film which is excellent in bending resistance and transparency and has a sufficient gas barrier property even under severe conditions.

[0010] It is another object of the present invention to provide a gas-barrier property, a boil-proof property, and a good anti- bending property and transparency.
An object of the present invention is to provide a gas barrier film having excellent retort properties and gelbo properties .

[0011]

That is, a gas barrier film according to claim 1 of the present invention is a gas barrier film in which a thin film composed of aluminum oxide and silicon oxide is formed on at least one surface of a plastic substrate. When the composition of the aluminum oxide and the silicon oxide in the thin film is expressed as (Al ₂ O _x ) _a SiO _Y , 2.5 ≦ X <3, 1.3 ≦ Y <2, However, when XY <5.9 and 0.03 ≦ a ≦ 3.0 , it is in a reduced state.
Um-silicon oxide thin film is deposited by vacuum evaporation.
Al ₂ O ₃ and SiO ₂ were used as additives,
Reaction on plastic film surface using hydrogen as a source
By performing sexual evaporation, it is characterized in der Rukoto those obtained.

Further, gas barrier film according to claim 2 of the present invention, on at least one surface of the plastic substrate, the gas barrier film including a thin film made of aluminum oxide and silicon oxide, in the thin film When the composition of the aluminum oxide and the silicon oxide is expressed as (Al ₂ O _X ) _a SiO _Y , 2.5 ≦ X <3, 1.3 ≦ Y <2, where XY < 5.9 and 0.03 ≦ a ≦ 3.0 , and in a reduced state, the reduced aluminum oxide
Um-silicon oxide thin film is deposited by vacuum evaporation.
Particulate _Al 2 _{O 3} and SiO ₂ used as a fee, Katsuko
Do not supply these deposition source materials with activated hydrogen gas.
Heat treatment and reactive deposition on plastic film surface
By performing, it is characterized in der Rukoto those obtained.

[0013]Further, claims 3 and 4 of the present invention.
According to the gas barrier film for retort, the value of the above a
Satisfies 0.6 ≦ a ≦ 3.0. Less than
Hereinafter, the present invention will be described in detail.

The plastic substrate in the present invention is a film obtained by melt-extruding an organic polymer, stretching the film in the longitudinal direction and / or the width direction, cooling, and heat setting as necessary. Organic polymers include polyethylene, polypropylene, polyethylene terephthalate, polyethylene-2,6-naphthalate, nylon 6, nylon 4,
Nylon 66, nylon 12, polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, wholly aromatic polyamide, polyamide imide, polyimide, polyether imide, polysulfone, polyphenylene sulfide, polyphenylene oxide, and the like. Among these, polyethylene terephthalate is preferred from the viewpoint of low heat shrinkage and low hygroscopic expansion. These organic polymers may be homopolymers or copolymers obtained by copolymerizing a small amount of copolymerizable monomers. Further, a blend of an organic polymer with another organic polymer may be used.

The plastic film used in the present invention is:
As the transparency, it is preferable to have a visible light transmittance of 50% or more. Having a visible light transmittance of 50% or more is suitable for use as a transparent gas barrier film. More preferred visible light transmittance is 80% or more.

The plastic film used in the present invention comprises:
The thickness is preferably in the range of 5 to 500 μm, and more preferably in the range of 8 to 300 μm.

Further, known additives such as an ultraviolet absorber, an antistatic agent, a plasticizer, a lubricant, and a coloring agent may be added to the organic polymer.

The plastic film used in the present invention is
As long as the object of the present invention is not impaired, the film may be subjected to corona discharge treatment, glow discharge treatment, other surface roughening treatment prior to lamination of the thin film layer, and a known anchor. Coating, printing and decoration may be applied.

The thin film according to the present invention comprises aluminum oxide and silicon oxide. That is, it is composed of a mixture or a compound of aluminum oxide and silicon oxide in a reduced state. Aluminum oxide is Al ₂ O ₃
And becomes aluminum or aluminum oxide such as Al, AlO, and Al ₂ O ₃ by reduction. The content of aluminum or aluminum oxide in the aluminum oxide differs depending on the conditions for forming the thin film. Further, silicon oxide is SiO ₂ , and Si, SiO,
It becomes silicon or silicon oxide such as SiO ₂ . The content of silicon or silicon oxide in silicon oxide also varies depending on the conditions for forming the thin film.

In the gas barrier film of the present invention, the composition of aluminum oxide and silicon oxide in the thin film is as follows: when both oxides are expressed as (Al ₂ O _x ) _a SiO _Y , 2.5 ≦ X <3 1.3 ≦ Y <2, where XY <5.9 and 0.03 ≦ a ≦ 3.0, indicating that the state is reduced.

The value of X represents the reduced state of Al ₂ O _3. For example, when X = 0, it is completely reduced and Al is in the metallic state. It indicates that ₂ O ₃ has a slight tendency to reduce. Similarly, the value of Y is
It represents the reduced state of O _2. For example, when Y = 0, it is completely reduced to Si, and 1.3 ≦ Y <2 is S
It indicates that iO ₂ has a slight tendency to reduce. Also, XY <
5.9 indicates that the Al ₂ O ₃ .SiO ₂ -based thin film is reduced. A represents the molar ratio of the number of Al atoms to the number of Si atoms in the thin film, and a = [(the number of Al atoms present in the film) / 2] × (the number of Si atoms present in the film).

In the present invention, the reduced state is determined by measuring the energy of electrons in Al and Si atoms in a thin film by ESCA (or X-ray photoelectron spectroscopy, also called XPS) or Auger electron spectroscopy.

That is, in ESCA, the reduced state of aluminum oxide is determined by decomposing the bond energy spectrum of electrons in Al atoms in the thin film into the bond energy spectrum of electrons in Al atoms in metallic aluminum and aluminum oxide. By weighting the spectrum of This is represented by the value of _X of Al ₂ O _X.
The reduced state of silicon oxide is obtained by decomposing the bond energy spectrum of electrons in Si atoms in the thin film into the bond energy spectrum of electrons in Si atoms such as silicon metal, silicon monoxide, and silicon dioxide. It is obtained by weighting the spectrum. This is represented by the value of Y in SiO _Y. Further, the abundance ratio of each atom in the film is found from the spectral intensity ratio of Al and Si, and the value of a is obtained. The target electrons in the above measurement are A
The electrons of l and Si must be the same, but it is particularly preferable that each of them has 2p electrons. However, it is not limited to this.

In Auger electron spectroscopy, the above E
By performing the same operation as in SCA on Auger electrons emitted from Al and Si atoms, the values of X, Y and a are obtained.

In the present invention, the values of X, Y and a are within the above-mentioned ranges, but when either X <2.5 or Y <1.3, the film is strongly colored and oxygen and water vapor Poor barrier properties. When a <0.03, the oxygen and water vapor barrier properties are poor. When XY ≧ 5.9, the initial barrier properties are good, but the gas barrier properties after the boil or the gelbo treatment are greatly deteriorated. When a> 3.0, the film is too hard and the initial barrier property of the film is excellent,
The mechanical properties, especially the gelbo properties, are inferior, and the gas barrier properties after the treatment are greatly deteriorated, which is not suitable for use as a gas barrier film.

The preferred values of X, Y and a in the gas barrier film of the present invention are 2.7 ≦ X <3, 1.5 ≦ Y <2, provided that XY <5.8 and 0.03 ≦ a ≦ 3.0, more preferably 2.8 ≦ X <3, 1.7 ≦ Y <2, where XY <5.5, and 0.06 ≦ a ≦ 2.0.

The composition of aluminum oxide and silicon oxide in the thin film of the gas barrier film for retort of the present invention is as follows: when both oxides are expressed as (Al ₂ O _x ) _a SiO _Y , 2.5 ≦ X <3, 1.3 ≦ Y <2, where XY <5.9, and 0.6 ≦ a ≦ 3.0, indicating a reduced state. Thus, X and Y
And the upper limit of a are the same as those in the gas barrier film described above, but the lower limit of a is 0.6. This is because a gas barrier film for retort requires higher oxygen and water vapor barrier properties, and a <0.6
In the case of the above, the oxygen and water vapor barrier properties become insufficient.

The preferred values of X, Y and a in the retort gas barrier film of the present invention are 2.7 ≦ X <3, 1.5 ≦ Y <2, provided that XY <5.8 and 0. 8 ≦ a ≦ 3.0, more preferably 2.8 ≦ X <3, 1.7 ≦ Y <2, provided that XY <5.5 and 1.0 ≦ a ≦ 3.0. is there.

In the present invention, a trace amount (up to 3% by weight with respect to all components of the thin film) of another component (impurity) is added to the thin film composed of aluminum oxide and silicon oxide within a range that does not impair the characteristics. May be included.

In the present invention, the thickness of the thin film is not particularly limited, but is preferably from 50 to 8000 °, more preferably from 70 to 5000 ° from the viewpoint of gas barrier properties and flexibility. .

The creation of the thin film in the present invention are needed use the vacuum deposition method. In vacuum evaporation method, using Al ₂ O ₃ and SiO ₂ as an evaporation source material, as a reactive gas to, with hydrogen, performing reactive vapor deposition on a plastic film surface. Further, as a deposition source material, particulate Al ₂
O ₃ and SiO ₂ were used, and these evaporation source materials were activated.
Heat treatment while supplying hydrogenated hydrogen gas, plus
Reactive deposition is performed on the surface of the tick film. In this case, it is preferable that the introduced gas is turned into plasma . The vacuum vapor deposition method, different heating method, resistance heating vapor deposition method, an induction heating deposition method, it is possible to use an electron beam evaporation method, or the like.
In addition, as long as the object of the present invention is not impaired, such as applying a bias to the substrate, heating or cooling the substrate, and the like, the production conditions may be changed . In the present invention, the thin film may be formed on only one side of the plastic film, or may be formed on both sides.

The gas barrier film of the present invention may be used as it is, or a film of another organic polymer or a thin layer may be laminated or coated on the film of the present invention.

[0033]

EXAMPLES Next , the examples of the present invention will be described with reference examples and comparative examples.
This will be described with an example .

[ Reference Example 1 ] ( Reference Example 1- I) Particulate Al having a size of about 3 to 5 mm was used as an evaporation source.
Aluminum oxide / silicon oxide reduced on a 12 μm thick PET film (Toyobo Co., Ltd .: E5100) by electron beam evaporation using (Purity 99.5%) and SiO ₂ (Purity 99.9%) A system thin film (about 800 mm thick) was formed. The above two kinds of vapor deposition materials are not mixed, the inside of the hearth is divided into two by a carbon plate, one electron gun (hereinafter referred to as EB gun) is used as a heating source, and each of Al and SiO ₂ is time-divided. And heated. At that time, the emission current of the EB gun was 2.0 A, the heating ratio (time ratio) to Al and SiO ₂ was 10:80, the flow rate of oxygen gas was 100 ccM, and the vacuum pressure during deposition was 8.5 × 10 ^{−. 4} Torr.
Further, the gas barrier film of the present invention was obtained at a film feed speed of 50 m / min and a chill roll cooling temperature of -10 ° C. Table 1 shows these film forming conditions.

The reduced state of the aluminum oxide / silicon oxide based thin film of the gas barrier film obtained in this manner is represented by E
It was measured by SCA, oxygen transmittance was measured as an initial gas barrier property, and light transmittance was measured as an optical property. Further, after elongating the gas barrier film by 3%, the oxygen permeability was measured.

Further, an unstretched polypropylene film (CPP film) having a thickness of 40 μm is dry-laminated on a vapor deposition surface of the gas barrier film using a two-component curable polyurethane-based adhesive (thickness: 4 μm), and packaged. A plastic film was obtained. After subjecting this packaging film to boil treatment (90 ° C., 30 minutes) or gelbo treatment, the oxygen permeability was measured.

Table 2 shows the above measurement results.

Next, the measurement and operation methods performed in the examples will be described.

<Measurement Method by ESCA> The measurement by ESCA was performed using ESCA-85 manufactured by Shimadzu Corporation.
0, the output was 9 KV × 30 mA using Mg-Kα ray (1254 ev) as a light source.

<Stretching Method of Gas Barrier Film> A sample set to a width of 10 cm and a length of 20 cm on a Tensilon of UTA-1T (manufactured by Orion Tech Co., Ltd.) was 6 mm (3%) at a speed of 1 mm / min. Stretched.

<Measurement Method of Light Transmittance> The absorption of visible light of the gas barrier film was measured using a U-3500 self-recording spectrophotometer (manufactured by Hitachi, Ltd.).
The light transmittance at 0 nm was determined. The level of zero absorption defined air as blank.

<Method of Measuring Oxygen Permeability> The oxygen permeability of the gas barrier film was measured using an oxygen permeability measuring device (OX-TRAN10 manufactured by Modern Controls).
0) was measured at 25 ° C. and 1 atm.

<Test Method for Bending Fatigue Resistance (hereinafter, Gelbo Characteristics)> The bending fatigue resistance was evaluated using a gelbo flex tester (manufactured by Rigaku Corporation). The condition is (MIL
-B131H), a sample piece of 112 inches × 8 inches was formed into a cylindrical shape having a diameter of 3.5 inches, both ends were held, the initial gripping interval was 7 inches, and the stroke was 3.5 inches.
h, an operation of applying a twist of 400 degrees was performed at a speed of 40 repetitions / min of repetition of the operation at 20 ° C. and a relative humidity of 65%.

The values of X, Y, and a indicating the reduced state of the thin film of the gas barrier film were determined from ESCA measurement data as follows.

For example, the case of Reference Example 1-1 will be described with reference to FIGS. FIG. 1 shows the results obtained by ESCA measurement, in the thin film of the gas barrier film of Reference Example 1-I .
It is a graph which shows the ratio of the existence number of Al atom and Si atom by the depth profile of ESCA. FIG. 2 is a spectrum chart showing the binding energy spectrum of 2p electrons in Al atoms in the thin film, and FIG.
4 is a spectrum chart showing a binding energy spectrum of 2p electrons in an atom.

First, from FIG. 1, the ratio of the number of atoms of Al: Si is 38:62, and therefore a = 0.31.

In FIG. 2, the binding energy spectrum of 2p electrons in Al atoms in the thin film is decomposed into the binding energy spectra of 2p electrons in trivalent and zero-valent Al atoms, and each spectrum is weighted. The calculation was performed based on these area ratios, and X was determined to be 2.88.

Similarly, in FIG. 3, the binding energy spectrum of 2p electrons in Si atoms in the thin film is
It is decomposed by the binding energy spectra of the 2p electrons in the valence, divalent and monovalent Si atoms, and the respective spectra are weighted by their area ratios to obtain Y = 1.58.

As described above, the composition of this thin film is (Al ₂ O
_2.9 ) _0.3 SiO _1.6 .

Reference Example 1- II to III Reference Example 1 except that the heating ratio of Al and SiO ₂ , the flow rate of oxygen gas, and the vacuum pressure during vapor deposition were changed as shown in Table 1.
A gas barrier film was obtained in the same manner as in -I.

For each of the obtained gas barrier films, the same measurement as in Reference Example 1-1 was performed. Table 2 shows the measurement results.

[Comparative Examples 1-I to V] Reference Example 1 except that the heating ratio of Al and SiO ₂ , the flow rate of oxygen gas, and the vacuum pressure during vapor deposition were changed as shown in Table 1.
A gas barrier film was obtained in the same manner as in -I.

For each of the obtained gas barrier films, the same measurement as in Reference Example 1-1 was performed. Table 2 shows the measurement results.

From Table 2, the initial oxygen permeability of the gas barrier films obtained in Reference Examples 1- I to III was 1 cc.
/ m was ² · 24h atm or less. After 3% elongation,
After 00 times Gelbo test, the results after the boiling test, the oxygen permeability remains in a slight increase, both 1cc / m ² · 24h at
m or less. Thus, the gas barrier properties of the films obtained in Reference Examples 1- I to III were extremely excellent. In addition, the light transmittance at 550 nm was 80% or more in each case, and a gas barrier film having excellent overall characteristics was obtained.

On the other hand, in Comparative Example 1-II (X <2.5) and Comparative Example 1-III (Y <1.3), the reduction state was too strong, the film was colored strongly, and the gas barrier property was poor. Inferior. In Comparative Example 1-IV (XY ≧ 5.9), the reduced state was too weak,
Although the initial gas barrier property is good, the gas barrier property after boiling is greatly deteriorated. Comparative Example 1-I (a <0.0
In the case of 3), the gas barrier property is inferior, and the barrier property after boiling is significantly deteriorated. In Comparative Example 1-V (a> 3), although the initial gas barrier properties were good, the gas barrier properties after 3% elongation and after the gelbo treatment were significantly deteriorated, and these were poor in the overall judgment.

[ Example 1 ] ( Example 1- I) As an evaporation source, particulate Al having a size of about 3 to 5 mm was used.
₂ O ₃ (purity 99.5%) and SiO ₂ (purity 99.9%)
%) And a 12 μm thick PET by electron beam evaporation.
A reduced aluminum oxide / silicon oxide based thin film was formed on a film (Toyobo Co., Ltd .: E5100).
The two kinds of vapor deposition materials were not mixed, the inside of the hearth was divided into two by a carbon plate, and one EB gun was used as a heating source, and Al ₂ O ₃ and SiO ₂ were heated in a time sharing manner. . At that time, the emission current of the EB gun was 2.5 A, the heating ratio to Al ₂ O ₃ and SiO ₂ was 10:10, and the hydrogen gas was activated by microwaves (2.54 GHz) to reduce the supply amount of hydrogen gas. At 60 ccM, the vacuum pressure during the deposition was 5.6 × 10 ⁻⁴ Torr. The film feed speed is 20 m / min, and the chill roll cooling temperature is -10.
As a result, the gas barrier film of the present invention having a film thickness of 3200 ° C was obtained. Table 3 shows these film forming conditions.

The reduced state of the aluminum oxide / silicon oxide based thin film of the gas barrier film thus obtained
It was measured by SCA, oxygen transmittance was measured as an initial gas barrier property, and light transmittance was measured as an optical property. Further, after elongating the gas barrier film by 3%, the oxygen permeability was measured.

Further, using this gas barrier film, a plastic film for packaging was produced in the same manner as in Reference Example 1, and the packaging film was subjected to a boil treatment (90
(° C., 30 minutes) or gelbo treatment, and then the oxygen permeability was measured.

Table 4 shows the results of the above measurements.

Example 1- II The emission current of the EB gun, the heating ratio of Al ₂ O ₃ and SiO ₂ , the supply amount of hydrogen gas, the vacuum pressure at the time of vapor deposition, and the film feed speed were changed as shown in Table 3. Example 1- I except for
In the same manner as in the above, a gas barrier film having a film thickness shown in Table 4 was obtained.

For each of the obtained gas barrier films, the same measurement as in Example 1-1 was performed. Table 4 shows the measurement results.

[Comparative Examples 2-I to V] As shown in Table 3, the emission current of the EB gun, the heating ratio of Al ₂ O ₃ and SiO ₂ , the supply amount of hydrogen gas, the vacuum pressure at the time of vapor deposition, and the film feed speed are shown in Table 3. Example 1- I except for changing
In the same manner as in the above, a gas barrier film having a film thickness shown in Table 4 was obtained.

For each of the obtained gas barrier films, the same measurement as in Example 1-1 was performed. Table 4 shows the measurement results.

From Table 4, the initial oxygen permeability of the gas barrier films obtained in Examples 1- I and II was 1 cc.
/ ^m and a ² · 24h atm or less, further, after 3% elongation, 20
After 0 times Gelbo test, the results after the boiling test, the oxygen permeability remains in a slight increase, both 1cc / m ² · 24h atm
It was below. Thus, the gas barrier properties of the films obtained in Examples 1- I and II were very excellent. In addition, the light transmittance at 550 nm was 80% or more in each case, and a gas barrier film having excellent overall characteristics was obtained.

On the other hand, in Comparative Example 2-II (X <2.5) and Comparative Example 2-III (Y <1.3), the reduced state was too strong, the color of the film was intense, and the gas barrier property was poor. Inferior. In Comparative Example 2-IV (XY ≧ 5.9), the reduced state was too weak,
Although the initial gas barrier property is good, the gas barrier property after boiling is greatly deteriorated. Comparative Example 2-I (a <0.0
In the case of 3), the gas barrier property is inferior, and the barrier property after boiling is significantly deteriorated. In Comparative Example 2-V (a> 3), although the initial gas barrier properties were good, the gas barrier properties after 3% elongation and after the gelbo treatment were significantly deteriorated, and these were poor in the overall judgment.

[ Reference Example 2 ] ( Reference Example 2- I) As an evaporation source, particulate Al having a size of about 3 to 5 mm was used.
Aluminum oxide / silicon oxide reduced on a 12 μm thick PET film (Toyobo Co., Ltd .: E5100) by electron beam evaporation using (Purity 99.5%) and SiO ₂ (Purity 99.9%) A system thin film (about 800 mm thick) was formed. The above two kinds of vapor deposition materials are not mixed, the inside of the hearth is divided into two by a carbon plate, and one EB is used as a heating source.
Using a gun, each of Al and SiO ₂ was heated in a time sharing manner. At that time, the emission current of the EB gun was 2.0 A, the heating ratio of Al to SiO ₂ was 10:80, the flow rate of oxygen gas was 100 ccM, and the vacuum pressure during deposition was 8.5 ×
10 ⁻⁴ Torr. The film feed speed is 50m
/ Min, the chill roll cooling temperature was -10 ° C, and the gas barrier film for retort of the present invention was obtained. Table 5 shows the film forming conditions.

The reduced state of the aluminum oxide / silicon oxide based thin film of the gas barrier film for retort thus obtained was measured by ESCA, oxygen transmittance was measured as an initial gas barrier property, and light transmittance was measured as optical characteristics. did. Furthermore, after stretching the gas barrier film by 3%,
The oxygen permeability was measured.

Further, an unstretched polypropylene film (CPP film) having a thickness of 40 μm was dry-laminated on the vapor deposition surface of the gas barrier film for retort using a two-component curing type polyurethane adhesive (thickness: 4 μm). Thus, a plastic film for packaging was obtained. For this packaging film, retort treatment (120 ° C, 30 minutes)
Alternatively, after the gelbo treatment, the oxygen permeability was measured.

Table 6 shows the above measurement results.

[0070] Except that (Reference Example 2 -II~III) Al and SiO ₂ heat ratio, the oxygen gas flow rate, and vacuum pressure during the deposition was varied as shown in Table 5 Reference Example 2
In the same manner as in -I, a gas barrier film for retort was obtained.

For each of the obtained gas barrier films for retort, the same measurement as in Reference Example 2- I was performed. Table 6 shows the measurement results.

Comparative Examples 3-I to IV Reference Example 2 except that the heating ratio of Al and SiO ₂ , the flow rate of oxygen gas, and the vacuum pressure during vapor deposition were changed as shown in Table 5.
A gas barrier film was obtained in the same manner as in -I.

For each of the obtained gas barrier films, the same measurement as in Reference Example 2- I was performed. Table 6 shows the measurement results.

As shown in Table 6, the gas barrier films for retorts obtained in Reference Examples 2- I to III all had a small initial oxygen permeability, and after elongation by 3%, after 200 times gelbo test and after retort test. In each case, the oxygen permeability only slightly increased, and was less than 1 cc / m ² · 24 h atm. As described above, the gas barrier properties of the retort films obtained in Reference Examples 2- I to III were extremely excellent. Further, the light transmittance at 550 nm was 80% or more in each case, and a gas barrier film for retort having excellent overall characteristics was obtained.

On the other hand, in Comparative Example 3-II (X <2.5) and Comparative Example 3-III (Y <1.3), the reduced state was too strong, the film was strongly colored, and the gas barrier property was poor. Inferior. In Comparative Example 3-I (XY ≧ 5.9), the reduction state was too weak,
Although the initial gas barrier property is good, the gas barrier property after retort is greatly deteriorated. In Comparative Example 3-IV (a> 3),
Although the initial gas barrier properties were good, the gas barrier properties after 3% elongation and after the gelbo treatment were significantly deteriorated, and these were poor in the overall judgment.

[ Example 2 ] ( Example 2- I) As an evaporation source, particulate Al having a size of about 3 to 5 mm was used.
₂ O ₃ (purity 99.5%) and SiO ₂ (purity 99.9%)
%) And a 12 μm thick PET by electron beam evaporation.
A reduced aluminum oxide / silicon oxide based thin film was formed on a film (Toyobo Co., Ltd .: E5100).
The two kinds of vapor deposition materials were not mixed, the inside of the hearth was divided into two by a carbon plate, and one EB gun was used as a heating source, and Al ₂ O ₃ and SiO ₂ were heated in a time sharing manner. . At that time, the emission current of the EB gun was 3.0 A, the heating ratio to Al ₂ O ₃ and SiO ₂ was 30:10, the hydrogen gas was activated by microwave (2.54 GHz), and the supply amount of hydrogen gas was reduced. At 50 ccM, the vacuum pressure at the time of vapor deposition was 5.8 × 10 ⁻⁶ Torr. The film feed speed is 15 m / min, and the chill roll cooling temperature is -10.
At 4 ° C., a gas barrier film for retort of the present invention having a thickness of 4800 ° was obtained. Table 7 shows these film forming conditions.

The reduced state of the aluminum oxide / silicon oxide-based thin film of the gas barrier film for retort thus obtained is measured by ESCA, oxygen transmittance is measured as an initial gas barrier property, and light transmittance is measured as optical characteristics. did. Furthermore, the oxygen permeability was measured after elongating the gas barrier film for retort by 3%.

Further, using this gas barrier film for retort, a plastic film for packaging was prepared in the same manner as in Reference Example 2, and the packaging film was subjected to retort treatment (120 ° C., 30 minutes) or gelbo treatment. , Oxygen permeability was measured.

Table 8 shows the above measurement results.

( Examples 2-II to III) As shown in Table 7, the emission current of the EB gun, the heating ratio of Al ₂ O ₃ and SiO ₂ , the supply amount of hydrogen gas, the vacuum pressure at the time of vapor deposition, and the film feed speed are shown in Table 7. Example 2- I except for changing
In the same manner as in the above, a gas barrier film for retort having a film thickness shown in Table 8 was obtained.

With respect to each of the obtained gas barrier films for retort, the same measurement as in Example 2- I was performed. Table 8 shows the measurement results.

[Comparative Examples 4-I to IV] The emission current of the EB gun, the heating ratio of Al ₂ O ₃ and SiO ₂ , the supply amount of hydrogen gas, the vacuum pressure at the time of deposition, and the film feed speed are shown in Table 7. Example 2- I except for changing
In the same manner as in the above, a gas barrier film having a film thickness shown in Table 8 was obtained.

For each of the obtained gas barrier films, the same measurement as in Example 2- I was performed. Table 8 shows the measurement results.

From Table 8, all the gas barrier films for retorts obtained in Examples 2- I to III have low initial oxygen permeability, and after elongation by 3%, after 200 times gelbo test and after retort test. In each case, the oxygen permeability only slightly increased, and was less than 1 cc / m ² · 24 h atm. Thus, the gas barrier properties of the retort films obtained in Examples 2- I to III were very excellent. Further, the light transmittance at 550 nm was 80% or more in each case, and a gas barrier film for retort having excellent overall characteristics was obtained.

On the other hand, in Comparative Example 4-II (X <2.5) and Comparative Example 4-III (Y <1.3), the reduced state was too strong, the color of the film was intense, and the gas barrier property was poor. Inferior. In Comparative Example 4-I (XY ≧ 5.9), the reduction state was too weak,
Although the initial gas barrier property is good, the gas barrier property after retort is greatly deteriorated. In Comparative Example 4-IV (a> 3),
Although the initial gas barrier properties were good, the gas barrier properties after 3% elongation and after the gelbo treatment were significantly deteriorated, and these were poor in the overall judgment.

[0086]

The gas barrier filter according to claim 1 of the present invention.
Lum , as mentioned above, is at least
On one side, a thin layer consisting of aluminum oxide and silicon oxide
In the gas barrier film layer is formed, when the composition of aluminum oxide and silicon oxide within the thin film, which represents both the oxide and _{(Al 2 O X) a SiO} Y, 2.5 ≦ X <3 1.3 ≦ Y <2, provided that XY <5.9 and 0.03 ≦ a ≦ 3.0 , and that the reduced aluminum oxide is in the reduced state.
Um-silicon oxide thin film is deposited by vacuum evaporation.
Al ₂ O ₃ and SiO ₂ were used as additives,
Reaction on plastic film surface using hydrogen as a source
Characteristics obtained by performing reactive evaporation.
The gas according to claim 2 of the present invention.
As described above, the svaria film is oxidized in the same reduced state.
Aluminum-silicon oxide thin film is formed by vacuum evaporation
Al ₂ O ₃ and SiO ₂ in particulate form used as evaporation source material
And these deposition source materials are activated hydrogen gas.
Heat treatment while supplying
Obtained by performing reactive deposition
In each case, the gas barrier
The film has excellent bending resistance and transparency, as well as gas barrier properties , boil resistance, retort resistance and gelbo properties.
Is excellent in both sexes, very excellent overall practical properties.

Further, according to the third and fourth aspects of the present invention.
According to the retort gas barrier film, since the value of a is 0.6 ≦ a ≦ 3.0, the gas barrier property after retort is also extremely excellent, and is suitable as a retort gas barrier film. .

[0088]

[Table 1]

[0089]

[Table 2]

[0090]

[Table 3]

[0091]

[Table 4]

[0092]

[Table 5]

[0093]

[Table 6]

[0094]

[Table 7]

[0095]

[Table 8]

[0096]

[Brief description of the drawings]

FIG. 1 is a graph showing the ratio of the number of Al atoms to the number of Si atoms present in a thin film of a gas barrier film of Reference Example 1-I as a depth profile of ESCA.

FIG. 2 shows the binding energy spectrum of 2p electrons in Al atoms in the thin film of the gas barrier film of Reference Example 1-I by ESCA, as indicated by the broken line (1) (2p electrons in trivalent Al atoms).
4 is a spectrum chart decomposed by a bond energy spectrum of electrons) and a broken line (2) (binding energy spectrum of 2p electrons in zero-valent Al atom). And the area of the spectrum of the broken lines 1 and 2 is shown.

FIG. 3 shows the bond energy spectrum of 2p electrons in Si atoms in the thin film of the gas barrier film of Reference Example 1-I by ESCA, as indicated by the broken line (11) (2p electrons in tetravalent Si atoms).
Electron binding energy spectrum), broken line (12) (2p electron binding energy spectrum in trivalent Si atom),
It is a spectrum chart decomposed by a broken line (13) (binding energy spectrum of 2p electrons in divalent Si atoms) and a broken line (14) (binding energy spectrum of 2p electrons in monovalent Si atoms). And the area of the spectrum of the broken line 1, the broken line 2, the broken line 3 and the broken line 4 is shown.

[Explanation of symbols]

(1) ... binding energy spectrum of 2p electrons in trivalent Al atoms (2) ... binding energy spectrum of 2p electrons in zero-valent Al atoms (11) ... binding energy of 2p electrons in tetravalent Si atoms Spectrum (12)… Binding energy spectrum of 2p electron in trivalent Si atom (13)… Binding energy spectrum of 2p electron in divalent Si atom (14)… Binding of 2p electron in monovalent Si atom Energy spectrum

──────────────────────────────────────────────────続 き Continuing from the front page (72) Yoshiharu Morihara, Inventor 2-1-1 Katata, Otsu-shi, Shiga Prefecture Toyo Spinning Co., Ltd. (72) Inventor Toshiyuki Otani 2-1-1 Katata, Otsu-shi, Shiga Prefecture Inside Toyo Spinning Co., Ltd. (72) Inventor Teiza Harima 2-1-1 Katata, Otsu City, Shiga Prefecture Inside Toyo Spinning Co., Ltd. (72) Inventor Yozo Yamada 2-1-1 Katata, Otsu City, Shiga Prefecture (56) References JP-A-5-179033 (JP, A) JP-A-3-23934 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B32B 1/00-35/00

Claims (4)

(57) [Claims] 1. A method according to claim 1, wherein at least one side of the plastic substrate has
In a gas barrier film on which a thin film composed of aluminum oxide and silicon oxide is formed, the composition of aluminum oxide and silicon oxide in the thin film indicates that both oxides are represented by (Al ₂ O _X ) _a SiO _Y. In this case, 2.5 ≦ X <3, 1.3 ≦ Y <2, where XY <5.9 and 0.03 ≦ a ≦ 3.0 , the reduced state is established, and the reduced state Aluminum oxide
Um-silicon oxide thin film is deposited by vacuum evaporation.
Al ₂ O ₃ and SiO ₂ were used as additives,
Reaction on plastic film surface using hydrogen as a source
By performing sexual deposition, gas, characterized in der Rukoto those obtained barrier film. 2. A plastic substrate on at least one side,
In a gas barrier film on which a thin film composed of aluminum oxide and silicon oxide is formed, the composition of aluminum oxide and silicon oxide in the thin film indicates that both oxides are represented by (Al ₂ O _X ) _a SiO _Y. In this case, 2.5 ≦ X <3, 1.3 ≦ Y <2, where XY <5.9 and 0.03 ≦ a ≦ 3.0 , the reduced state is established, and the reduced state Aluminum oxide
Um-silicon oxide thin film is deposited by vacuum evaporation.
Particulate _Al 2 _{O 3} and SiO ₂ used as a fee, Katsuko
Do not supply these deposition source materials with activated hydrogen gas.
Heat treatment and reactive deposition on plastic film surface
By performing, to characterized der Rukoto those obtained
Ruga scan barrier film. 3. A plastic substrate on at least one side,
Thin film composed of aluminum oxide and silicon oxide is formed
The gas barrier film,
The composition of minium oxide and silicon oxide forms both oxides (A
When expressed as l ₂ O _X ) _a SiO _Y , 2.5 ≦ X <3, 1.3 ≦ Y <2, provided that XY <5.9 and 0.6 ≦ a ≦ 3.0 , have been made with the reduced state, aluminum oxide silicon oxide based thin film of the reduced state by a vacuum deposition method using Al ₂ O ₃ and SiO ₂ as an evaporation source material, using hydrogen as a reactive gas to, JP that by reactive deposition on plastic film surfaces are those obtained
Gas barrier film for retort . 4. A plastic substrate on at least one side,
Thin film composed of aluminum oxide and silicon oxide is formed
The gas barrier film,
When the compositions of the minium oxide and the silicon oxide represent both oxides as (Al ₂ O _X ) _a SiO _Y , 2.5 ≦ X <3, 1.3 ≦ Y <2, where XY <5 0.9 and 0.6 ≦ a ≦ 3.0 , and the reduced aluminum oxide / silicon oxide based thin film is formed into a particulate Al ₂ O as a deposition source material by a vacuum deposition method. with ₃ and SiO _2, and these deposition source materials, heat treatment while supplying activated hydrogen gas, characterized in that by reactive deposition on plastic film surfaces are those obtained Toss
Retort gas barrier film.