JPH08290517A - Method for coating packaging material consisting of plastic sheet with silica thin film with excellent gas barrier property - Google Patents

Abstract

PURPOSE: To provide a method for preparing a packaging material with excellent gas barrier properties. CONSTITUTION: A high frequency electrode 3 facing to one face of a packaging material consisting of a plastic sheet and with a Tg being higher than the film forming temp. of a silica thin film and with a distance with the coating face of at most 10mm and being approximately const., is arranged and an earth electrode 2 facing to another face of the sheet and with a distance with the coating face being larger than the distance between the high frequency electrode and the coating face and being approximately const. is arranged through the sheet and by facing it to the high frequency electrode 3 and a plasma of silica formed by means of a CVD method is introduced between the sheet and the electrode and it is sticked on the surface of the sheet under a discharging gas pressure of 0.0005-0.050Torr with a uniform film thickness.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of coating a packaging material made of a plastic sheet with a thin film of a transparent silicon compound having an excellent gas barrier property.

[0002]

2. Description of the Related Art Packaging materials are required to prevent gas permeation in order to protect and preserve their contents, and various attempts have been made so far. For example, attempts have been made to provide an inorganic coating layer such as silicon oxide or aluminum oxide, laminate a gas barrier resin layer such as polyvinylidene chloride, or laminate a metal film of aluminum foil. In addition to this, JP-A-3-1837
In Japanese Patent Publication No. 59, a plastic film is coated with the same synthetic resin as the plastics in a thin film form by vacuum vapor deposition or sputtering to form an organic substance layer, and an inorganic substance is vapor-deposited thereon to form a mixed layer of the organic substance and the inorganic substance. A laminated film is shown which has been formed and on which an inorganic layer has been formed. Since this plastic is a substance that is completely different from the inorganic substance of the coating layer and has a poor affinity, the same synthetic resin is coated on the plastic in a thin film form, and in order to improve the fixing property of the inorganic coating, a synthetic resin is used in the middle. Although the blend layer of the inorganic material is formed, the surface of the blend layer has not only the surface of the inorganic material but also the surface of the synthetic resin, so that the fixing property of the inorganic material layer is not improved as expected. Further, since the synthetic resin has a reduced molecular weight when vapor-deposited, the inorganic thin film formed thereon does not form a film excellent in gas barrier property. The present inventor has previously disclosed the invention of Japanese Patent Application Laid-Open No. 5-345383 and Japanese Patent Application No. 5-2249.
No. 03 Invention filed. These inventions are epoch-making inventions which are completely different from the conventional packaging materials, and the drawbacks of the conventional packaging materials have been solved. However, there were some inadequate points in forming a highly gas barrier coating having an ultra-precise and uniform film thickness of 0.1 g / m ² day. For special applications, such as packaging of special chemicals, ultra-precise film thickness and high gas barrier property are required.

[0003]

SUMMARY OF THE INVENTION According to the present invention, a plastic sheet-shaped packaging material is coated with an ultra-dense inorganic film,
It provides high gas barrier performance.

[0004]

MEANS FOR SOLVING THE PROBLEMS The present invention provides "1. The distance from the covering surface facing one surface of the packaging material made of a plastic sheet having a TG higher than the film forming temperature of the silicon oxide thin film is 10 mm or less. A high-frequency electrode that is almost constant is installed, and a ground electrode that faces the other surface of the sheet and has a substantially constant distance from the covering surface that is larger than the distance between the high-frequency electrode and the covering surface is connected to the high-frequency electrode through the sheet. They are arranged so as to face each other, and a plasma of silicon oxide generated by the CVD method is introduced between the sheet and the electrode so that the discharge gas pressure is 0.0.
A method for coating a packaging material made of a plastic sheet with a silicon oxide thin film having an excellent gas barrier property, which comprises depositing a uniform film thickness on a sheet surface at 005 to 0.05 torr. 2. A method for coating a packaging material made of the plastic sheet according to item 1, wherein the high-frequency electrode is a single electrode having a smooth flat outer surface, with a silicon oxide thin film having an excellent gas barrier property. 3. A method of coating a packaging material made of the plastic sheet according to item 1 or 2 with a silicon oxide thin film having an excellent gas barrier property, wherein the ground electrode is a single electrode having a smooth flat outer surface. 4. A silicon oxide thin film formed on a packaging material made of a plastic sheet has a refractive index of 1.4 to 1.5 and a film thickness of 30.
A method of coating a packaging material comprising a plastic sheet according to any one of items 1 to 3 having a thickness of 0 to 2000Å with a silicon oxide thin film having an excellent gas barrier property. 5. From the film forming temperature of the silicon oxide thin film, the T. G. A high-frequency electrode having a substantially constant distance of 10 mm or less from the covering surface is provided facing one surface of the packaging material made of a high-quality plastic sheet, and the distance from the covering surface is facing the other surface of the sheet. A ground electrode, which is larger than the distance between the high-frequency electrode and the covering surface and is substantially constant, is placed opposite to the high-frequency electrode via a sheet, and an organosilicon compound composed of at least silicon, oxygen, and carbon is formed into plasma by the low-temperature plasma method. , The plasma is supplied between the sheet and the electrode, and the gas pressure is 3
Polymerization at × 10 ^{−3 to} 3 × 10 ⁻² torr forms a silicon compound thin film on the surface of the sheet, and then plasma of silicon oxide generated by the CVD method is introduced between the sheet and the electrode to discharge gas pressure. A method of coating a packaging material made of a plastic sheet with a silicon oxide thin film excellent in gas barrier property, which comprises forming a silicon oxide coating on a silicon compound polymer thin film at 0.0005 to 0.05 toor . 6. A method of coating a packaging material composed of a plastic sheet according to item 5, wherein the high-frequency electrode is a single electrode having a smooth flat outer surface, with a silicon oxide thin film having excellent gas barrier properties. 7. A method for coating a packaging material comprising a plastic sheet according to item 1 or 6 with a silicon oxide thin film having excellent gas barrier properties, wherein the ground electrode is a single electrode having a smooth flat outer surface. 8. The silicon compound polymer coating has a refractive index of 2.0 to 2.3.
And the film thickness is 0.005 μm to 0.05 μm, the silicon oxide film has a refractive index of 1.4 to 1.5, and the film thickness is 300 to 20.
A method for coating a packaging material, which is 00 Å and is made of the plastic sheet according to any one of 5 to 7, with a silicon oxide thin film having an excellent gas barrier property. Regarding

[0005]

The first feature of the present invention, which has a special effect, is that the distance from the one surface of the sheet-like packaging material to the covering surface is 10
A high-frequency electrode that is almost constant at less than mm is installed, and a ground electrode whose distance between the covering surface of the sheet and the electrode surface is larger than the distance between the high-frequency electrode and the covering surface is almost constant is provided on the other surface of the sheet. That is, it is arranged so as to face the high-frequency electrode. The reason why the distance between the electrode and the surface of the sheet is kept constant is to keep the electric field strength distribution constant. The distance between the high frequency electrode and the sheet covering surface should be 10 mm or less. This is because if the thickness is 10 mm or more, the electric field strength is weak, and a problem such as a dense film not being formed occurs.

A second feature of the present invention is that one high-frequency electrode and one earth electrode are arranged to face each other with a sheet interposed therebetween. By using such a pair of electrodes together, the intensity distribution of the electric field becomes precisely constant, the thickness of the formed film becomes uniform, and the film quality becomes dense and uniform.

A third feature of the present invention is that a plasma of silicon oxide is generated by using the CVD method and the discharge gas pressure is 0.00.
The inner surface of the container is coated at 05 to 0.05 torr. If the gas pressure is not within this range, problems such as the formation of a dense film may occur.

A fourth feature of the present invention is that, as a plastic sheet for coating, the T.S.
G. Is to use a sheet formed of high plastics material. This is because in order to form an ultra-precision thin film, it is necessary to avoid deformation of the sheet during film formation. Such first to fourth characteristics are combined,
The silicon oxide plasma is introduced between the electrode and the sheet. Since the electric field strength distribution during this period is constant, the plasma concentration becomes constant and the silicon oxide is deposited and coated on the sheet with a dense and uniform thickness.

Thus, a dense and constant-thickness silicon oxide film is formed. There must be only one high-frequency electrode and one ground electrode, and the use of multiple electrodes must be avoided. It is preferable that the outer surface of the ground electrode is smooth and flat because coating with a uniform thickness can be performed. If a plurality of electrodes are used, a dense and uniform coating cannot be formed even if the CVD method is used. The present inventor has variously studied why a dense and uniform film is not formed. For example, as shown in FIG. 3, a plurality of electrodes are arranged on the surface of the sheet, and CVD is performed.
When the silicon oxide was coated by the method, the thickness of the coating became uniform by transporting the sheet at a constant speed, but a film excellent in gas barrier property was not formed.

Since the present inventor uses a plurality of electrodes, the electric field intensity distributions of the respective electrodes interfere with each other and affect each other, and the electric field intensity and plasma concentration change. The gas barrier property is not improved and the film thickness is not uniform. When the sheet is conveyed, the film thickness is uniform, but the barrier property of the film is not improved.
Although the present invention uses the CVD method, the CVD method using high frequency, alternating current, and direct current is used.

The silicon oxide film formed according to the present invention has a refractive index of 1.4 to 1.5 and a film thickness of 300 to 2000Å. If the film thickness is less than 300Å, a continuous film cannot be obtained and the gas barrier property is not improved, and even if the film is coated over 2000Å, the gas barrier property is not significantly improved, and conversely the film is broken by internal stress. A problem arises. The material used for forming the silicon oxide plasma by the CVD method in the present invention is
SiH ₄ and NO _x gas and oxygen gas, or organosilicon compounds such as TEOS (tetraethoxysilane) and HDSO (hexamethyldisiloxane) and NO _x and oxygen gas, and He, Ar and the like as plasma auxiliary gas are also used. The silicon oxide film thus formed has an excellent gas barrier effect and is a very excellent sheet-like packaging material for ordinary applications.

The present invention is also based on the T.V. G. A high-frequency electrode having a substantially constant distance of 10 mm or less from the covering surface is provided facing one surface of the packaging material made of a high-quality plastic sheet, and the distance from the covering surface is facing the other surface of the sheet. A ground electrode, which is larger than the distance between the high-frequency electrode and the covering surface and is substantially constant, is placed opposite to the high-frequency electrode via a sheet, and an organosilicon compound composed of at least silicon, oxygen, and carbon is formed into plasma by the low-temperature plasma method. The plasma was supplied between the sheet and the electrode, and polymerized at a gas pressure of 3 × 10 ^{−3 to} 3 × 10 ⁻² torr to form a silicon compound polymer thin film on the surface of the sheet, and then generated by a CVD method. A plasma of silicon oxide is introduced between the sheet and the electrode to make the discharge gas pressure 0.000.
Also included is a method of coating a packaging material made of a plastic sheet with a silicon oxide thin film having excellent gas barrier properties, which comprises forming a silicon oxide coating on the silicon compound polymer thin film at 5 to 0.05 torr. To do. The coating composed of these two layers has excellent gas barrier properties and a water vapor transmission rate of 0.
It exhibits a very high water vapor barrier effect of 1 g / m ² day or less. When this silicon compound film and silicon oxide film are formed by disposing a high frequency electrode and a ground electrode which are opposed to each other with a sheet interposed therebetween, a uniform film is formed for both films, and the gas barrier property is significantly improved. .

Although it is not necessarily scientifically elucidated as to why these two kinds of layers have such a special effect when laminated in this order, the present invention has the effect of repetitive reproduction. The present inventors consider that the gas blocking effect of the silicon oxide layer is largely due to the stable fixing property of the silicon oxide fine particles supplied onto the coated substrate. That is, the supplied particles move on the plastic substrate and are stabilized and fixed at the most stable place. In this case, when a polymer film of a silicon compound containing silicon, carbon and oxygen is formed on the plastic substrate, the silicon oxide fine particles are well stabilized and fixed. It is considered that the distribution becomes uniform, and the silicon oxide fine particles are further stacked on the stabilized silicon oxide particles to form a silicon oxide coating, resulting in a tight coating. Further, it is more preferable that the silicon compound polymer coating of the high-frequency electrode layer and the silicon oxide coating of the ground layer have a super-water vapor gas barrier property of 0.1 g / m ² day or less when they are within the respective ranges of specific refractive indexes. High fixability,
It is believed that this is because the film is tight and has few defects.

The first organic silicon compound polymer coating layer is silicon 1 in the composition of silicon, carbon and oxygen in the high frequency electrode layer.
More than 5%, more than 20% carbon and the rest oxygen
It is a thin layer of 0.005 μm to 0.05 μm. If the thickness of the coating layer is thicker than this, the gas barrier property deteriorates.

Such a special organosilicon compound polymer coating can be formed, for example, by plasmaizing an organosilicon compound monomer such as hexamethyldisilane and polymerizing it on a plastic substrate. The refractive index of the coating film formed by adjusting the gas pressure during the polymerization from 3 × 10 ⁻³ to 3 × 10 ⁻² torr is 2.0 to
It can be 2.3. Conventionally, the plasma CVD method, which is known to have other uses, has a discharge gas pressure of 0. Number t
Since it is in the range of orr to several + torr, it can be seen that the plasma CVD method used in the present invention is special.

Examples of the organosilicon compound monomer used in the present invention include vinyltriethoxysilane, vinyltrimethoxysilane, tetramethoxysilane, tetraethoxysilane, phenyltrimethoxysilane, octamethylcyclotetrasiloxane, methyltrimethoxysilane, and methyltrimethoxysilane. Examples include ethoxysilane, 1133-tetramethyldisiloxane, and hexanemethyldisiloxane.

[0017]

EXAMPLES The present invention will be described with reference to examples for the sake of easy understanding.

Example 1 FIG. 5 shows a high frequency plasma CVD apparatus for forming an organic silicon compound film used in the present invention. This device is a stainless steel bell jar type vacuum chamber 1 with a diameter of 60 cm equipped with an inlet 6 and an oxygen gas inlet 7 for introducing silane and room temperature liquid monomer in a gaseous state, and a high frequency power source 5 (13.56 MH manufactured by JEOL Ltd.). _z , 1.5KW, J
EH-01B) and matching box 4 and diameter 1
3 cm disk-shaped high frequency electrode 3, diameter 20 cm, height 1.
It consists of a 5 cm cylindrical ground electrode 2, a sample jig 8 placed between both electrodes, and the like. The apparatus of FIG. 5 can perform both the coating of an organic silicon compound and the coating of a silicon oxide film which is a gas barrier layer. As the vacuum pump, an oil rotary pump and an oil diffusion pump were used. During the pretreatment and film formation, the pump was continuously pulled to perform the pretreatment and the thin film coating test. Hexamethyldisiloxane (hereinafter referred to as HMDSO) was used as the room temperature liquid monomer, and oxygen gas was used as the reaction gas. These gases are introduced into the chamber by different routes, mixed in the ground electrode and discharged into the chamber. The ground electrode and the high-frequency electrode are arranged in parallel (distance 7 cm), and a 100 μ polycarbonate (hereinafter referred to as PC) sheet is attached by an insulating sample jig.
It was placed between the high frequency electrode and the ground electrode (5 mm from the high frequency electrode). The degree of vacuum in the chamber is 2 to 3 × 10 ^-5 torr (ionization vacuum gauge) by an oil rotary pump and an oil diffusion pump.
To a vacuum until the degree of vacuum in the chamber is 2 × 10 ⁻³ t
Oxygen gas is introduced until the pressure reaches orrr, and then HMDSO is applied until the degree of vacuum in the chamber reaches 4 × 10 ⁻³ torr.
Introduced steam. An incident power of 200 W was introduced from a high-frequency power source into the chamber through a matching box to generate a mixed plasma of oxygen and HMDSO, which was held for 2 minutes to form a silicon oxide film on the PC sample. The water vapor transmission rate of this laminate was measured with a water vapor transmission rate measuring device manufactured by Mocon, and is shown in Table 1.

Example 2 and Comparative Example 1 The position of the sample placed between the high frequency electrode and the ground electrode was 3, 5, 7, 9, 23 and 40 mm on the high frequency electrode substrate.
The silicon oxide film was formed on the PC sample under the same conditions as in Example 1 except that it was installed in the above, and the amount of water vapor permeation was measured.

[0020]

[Table 1]

Example 3 and Comparative Example 2 Under the same conditions as in Example 1 except that a plastic sheet having a thickness of 100 μm to 280 μm and a glass transition temperature (hereinafter referred to as Tg) of −15 ° C. to 105 ° C. was used as the sample. , Forming a silicon oxide film on the sample, measuring the amount of water vapor transmission,
The results are shown in Table 2. As a result of measuring the temperature of the sample surface with an optical fiber type thermometer, it was 45 ° C. under this condition.

[0022]

[Table 2]

Example 4 The high frequency electrode, the ground electrode and the sample substrate holder in the apparatus shown in FIG. 5 were removed, and the width as shown in FIG.
cm High-frequency electrode with a length of 20 cm, width 10 cm, rectangular ground electrode with a length of 20 cm, and 2 m above the high-frequency electrode.
P of 100μ that moves the position of m at a speed of 10 cm per minute
A silicon oxide film was formed on a PC sample under the same conditions as in Example 1 except that a C (polycarbonate) sheet was arranged, and the film thickness and the refractive index of the film were measured by an ellipsometer and shown in Table 3. The water vapor transmission rate of this laminate is 0.03.
g / m ² day at 40 ° C. 90% RH. The unit of film thickness is angstrom.

[0024]

[Table 3]

Comparative Example 3 Four high-frequency electrodes having a width of 10 cm and a length of 5 cm as shown in FIG. 3 are arranged at a distance of 3 cm below the sheet 2 mm, and an earth electrode has a width of 10 cm and a length of 30 cm. As a result of coating the silicon oxide film under the same conditions as in Example 4 except that the sample was placed 50 mm, the film thickness was 950 Å to 1020 Å at any measurement point, but the water vapor transmission rate of the laminate was 2 to 5 g. / M ² day at 40 ° C 90
% RH.

Example 5 A sheet-shaped polyethylene naphthalate (hereinafter referred to as PEN) sample was used, and an HMDSO polymer film and a silicon oxide film were formed on the surface of the sheet by using the apparatus shown in FIG. As the coating method, PEN was used for the sheet material, the distance between the high frequency electrode and the sample surface was 2 mm, and the coating was performed under the same conditions as in Example 1 except for the conditions described below. The degree of vacuum in the chamber is 2 to 3x due to the oil rotary pump and the oil diffusion pump.
A vacuum is drawn up to 10 ⁻⁵ torr (ionization vacuum gauge), and the HM is adjusted until the degree of vacuum in the chamber reaches 4 × 10 ⁻³ torr.
DSO vapor was introduced. Incident power from high frequency power source 400
W is introduced into the chamber through the matching box, HMDSO plasma is generated and held for 1 minute,
An HMDSO polymer coating was formed on the surface of the sheet PEN sample. Then, the vacuum degree in the chamber was evacuated to 2-3 × 10 ⁻⁵ torr by an oil rotary pump and an oil diffusion pump, and a silicon oxide film was formed on the HMDSO polymer film in the same manner as in Example 1. . As a result of measuring the amount of water vapor permeation through a bottomed cylindrical container coated with this thin film, 0.02 g
/ M ² day (40 ° C 90% RH).

Example 6 The high frequency electrode, the ground electrode and the sample substrate holder in the apparatus shown in FIG. 5 were removed, and the width was 10 as shown in FIG.
cm, diameter 13 cm, cylindrical high frequency electrode and width 10 c
m, 23 cm in diameter, a semi-cylindrical earth electrode, and 100 μP that moves on the high-frequency electrode at a speed of 10 cm / min.
A silicon oxide film was formed on a PET sample under the same conditions as in Example 1 except that an ET (polyethylene terephthalate) sheet was placed, and the film thickness and the refractive index of the film were measured by an ellipsometer and shown in Table 4. . The water vapor transmission rate of this laminate was 0.03 g / m ² day at 40 ° C. 90% RH. The unit of film thickness is angstrom.

[0028]

[Table 4]

Comparative Example 4 A silicon oxide film was formed on a PET sample under the same conditions as in Example 6 except that a cylindrical high frequency electrode having a width of 10 cm and a diameter of 13 cm shown in FIG. It was formed and the film thickness and water vapor transmission amount were measured. As a result, the film thickness was uniform in the range of 920Å to 980Å, but the amount of water vapor permeation of the film was 1 to ² g / m ² dayat 40 ° C 90.
% RH and gas barrier performance were low.

Example 7 100 μ of sheet-like cyclic olefin copolymer (CO
Using C) as a sample, an HMDSO polymer film and a silicon oxide film were formed on the surface of the sheet-shaped sample using the apparatus shown in FIG. The coating method was the same as in Example 5 except for the sample material and the following conditions. The degree of vacuum in the chamber is 2 to 3 x 10 by the oil rotary pump and the oil diffusion pump.
Pull a vacuum to ^-5 torr (by ionization gauge), chamber vacuum of 3 × ^{10 -} 3 torr~10 × ¹⁰
HMDSO vapor was introduced until ^-3 torr. Injecting 400W of incident power from the high frequency power supply into the chamber,
HMDSO plasma was generated and held for 1 minute to form a HMDSO polymer coating on the outer surface of the bottomed cylindrical container. Then, the vacuum degree in the chamber was evacuated to 2-3 × 10 ⁻⁵ torr by an oil rotary pump and an oil diffusion pump, and a silicon oxide film was formed on the HMDSO polymer film in the same manner as in Example 6. . The amount of water vapor permeation was measured by an ellipsometer for the refractive index and the film thickness of the bottomed cylindrical container coated with these films, and by the gravimetric method.
It was shown to.

[0031]

[Table 5]

(Note) HMDSO concentration unit; × 10 ⁻³ torr film thickness unit; Angstrom water vapor transmission amount unit; g / m ² day, at 40 ° C. 90
% RH

Comparative Example 5 The concentration of HMDSO was 1.5 × 10 ⁻³ torr and 20.
The refractive index and the film thickness of the HMDSO film coated on the surface of the same sheet-shaped COC sample as in Example 7 were measured by an ellipsometer at 10 × ^{3 −3} torr and the coating time of the HMDSO film was 0.2 and 5 minutes. And also HMDSO
The water vapor permeation amount of the film and the silicon oxide laminated film is measured by a gravimetric method,
The results are shown in Table 6.

[0034]

[Table 6]

(Note) HMDSO concentration unit; × 10 ⁻³ torr HMDSO film thickness; Angstrom bilayer film water vapor transmission amount unit; g / m ² day, at4
0 ° C 90% RH

Example 8 A sheet-shaped cyclic olefin copolymer (COC) was used as a sample, and H was applied to the surface of the sheet-shaped sample using the apparatus shown in FIG.
An MDSO polymer coating and a silicon oxide coating were formed. The coating method was the same as in Example 7 except for the sample material and the following conditions. The degree of vacuum in the chamber is set to 2-3 × 10 ⁻⁵ torr by an oil rotary pump and an oil diffusion pump.
A vacuum was drawn up (by an ionization vacuum gauge), and HMDSO vapor was introduced until the degree of vacuum in the chamber reached 4 × 10 ⁻³ torr. An incident power of 400 W was introduced into the chamber from a high frequency power source, HMDSO plasma was generated and held for 1 minute, and an HMDSO polymer film was formed on the surface of the sheet-shaped COC sample. Then, the degree of vacuum in the chamber is evacuated to 2-3 × 10 ⁻⁵ torr by an oil rotary pump and an oil diffusion pump, and the concentration ratio of HMDSO vapor and oxygen (the ratio of the degree of vacuum in the chamber measured by an ionization vacuum gauge; HMDSO / oxygen). ) Is in the range of 0.5 to 2.5 and the coating time of the silicon oxide film is 5 to 20 minutes in the same manner as in Example 6 except that the HMD is used.
A silicon oxide film was formed on the SO polymer film. The water vapor permeation amount was measured by an ellipsometer for the refractive index and the film thickness of the film on the sheet-shaped COC sample coated with these films, and shown in Table 7.

[0037]

[Table 7]

(Note) A unit of film thickness of the silicon oxide film; a unit of water vapor transmission amount of the Angstrom two-layer film; g / m ² day, at4
0 ° C 90% RH

Comparative Example 6 The concentration ratio of HMDSO vapor and oxygen (ratio of degree of vacuum in chamber by ionization vacuum gauge; HMDSO / oxygen) is 0.2 to.
A film of silicon oxide was formed on the HMDSO polymerized film in the same manner as in Example 8 except that the coating time was 5, and the coating time of silicon oxide was 2 minutes and 25 minutes. The refractive index and the film thickness of the film on the surface of the sheet-shaped COC sample coated with these films were measured by an ellipsometer and by a gravimetric method, and are shown in Table 8.

[0040]

[Table 8]

(Note) A unit of film thickness of a silicon oxide film; a unit of water vapor transmission amount of an Angstrom two-layer film; g / m ² day, at4
0 ° C 90% RH

[0042]

According to the present invention, since a silicon oxide thin film having a uniform film thickness and a constant range of refractive index is formed on a three-dimensional plastic packaging material, a packaging material having an excellent gas barrier property can be provided.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of an embodiment of the present invention.

FIG. 2 is an explanatory diagram of a high frequency electrode and a ground electrode according to an embodiment of the present invention.

FIG. 3 is an explanatory diagram of a comparative example.

FIG. 4 is an explanatory diagram of a comparative high frequency electrode and a ground electrode.

FIG. 5 is an explanatory diagram of a CVD apparatus.

[Explanation of symbols]

 1 Cylindrical container 2 Earth electrode 3 High frequency electrode 4 Matching box 5 High frequency power supply 6 Gas inlet 7 Gas inlet 8 Jig for sample

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location C08J 7/06 C08J 7/06 Z C23C 16/50 C23C 16/50

Claims (8)

[Claims] 1. From the film forming temperature of a silicon oxide thin film, T. G.
A high-frequency electrode having a substantially constant distance of 10 mm or less from the covering surface is provided facing one surface of the packaging material made of a high-quality plastic sheet, and the distance from the covering surface is facing the other surface of the sheet. An earth electrode, which is larger than the distance between the high-frequency electrode and the covering surface and is substantially constant, is arranged to face the high-frequency electrode through the sheet, and plasma of silicon oxide generated by the CVD method is introduced between the sheet and the electrode. A method for coating a packaging material made of a plastic sheet with a silicon oxide thin film having an excellent gas barrier property, which comprises depositing a uniform film thickness on a sheet surface at a discharge gas pressure of 0.0005 to 0.05 torr. 2. The packaging material made of the plastic sheet according to claim 1, wherein the high-frequency electrode is a single electrode having a smooth flat outer surface, and is covered with a silicon oxide thin film having excellent gas barrier properties. how to. 3. A silicon oxide thin film having an excellent gas barrier property in a packaging material made of the plastic sheet according to claim 1 or 2, wherein the ground electrode is a single electrode having a smooth flat outer surface. How to coat. 4. The silicon oxide thin film formed on the packaging material made of a plastic sheet has a refractive index of 1.4 to 1.5 and a film thickness of 300 to 2000Å. A method for coating a packaging material comprising the described plastic sheet with a silicon oxide thin film having an excellent gas barrier property. 5. From the film forming temperature of the silicon oxide thin film, T. G.
A high-frequency electrode having a substantially constant distance of 10 mm or less from the covering surface is provided facing one surface of the packaging material made of a high-quality plastic sheet, and the distance from the covering surface is facing the other surface of the sheet. A ground electrode, which is larger than the distance between the high-frequency electrode and the covering surface and is substantially constant, is placed opposite to the high-frequency electrode via a sheet, and an organosilicon compound composed of at least silicon, oxygen, and carbon is formed into plasma by the low-temperature plasma method. The plasma is supplied between the sheet and the electrode and polymerized at a gas pressure of 3 × 10 ^{−3 to} 3 × 10 ⁻² torr to form a silicon compound thin film on the surface of the sheet, and then silicon oxide generated by the CVD method. The discharge gas pressure is 0.0005 to 0.05 toor by introducing the plasma of the object between the sheet and the electrode.
A method of coating a packaging material made of a plastic sheet with a silicon oxide thin film having excellent gas barrier properties, which comprises forming a silicon oxide coating on the silicon compound polymer thin film. 6. The packaging material made of the plastic sheet according to claim 5, wherein the high-frequency electrode is a single electrode having a smooth flat outer surface, and is covered with a silicon oxide thin film having excellent gas barrier properties. how to. 7. A silicon oxide thin film excellent in gas barrier property for a packaging material comprising a plastic sheet according to claim 1 or 6, wherein the ground electrode is a single electrode having a smooth flat outer surface. How to coat. 8. The silicon compound polymer coating has a refractive index of 2.0.
To 2.3, the film thickness is 0.005 μm to 0.05 μm, and the silicon oxide film has a refractive index of 1.4 to 1.5 and a film thickness of 3
A method for coating a packaging material comprising a plastics sheet according to any one of claims 5 to 7 having a thickness of 00 to 2000Å with a silicon oxide thin film having an excellent gas barrier property.