JPS60219042A - Permeability-resistant transparent synthetic resin body - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a moisture permeable synthetic resin body, particularly to a synthetic resin body having a transparent thin film having excellent moisture permeability on a transparent synthetic resin base material.

(Prior Art) Packaging materials, especially packaging materials used for packaging foods, medicines, chemical products, etc., must have moisture permeation resistance to prevent the contents from deteriorating in quality.

In the field of electronics industry, there is also a need for EL elements having moisture-proof protective films. For this purpose, conventionally, for example, aluminum foil is bonded to a synthetic resin base film to take advantage of the moisture permeability property of the aluminum foil.

The packaging material in this case is.

Although it has excellent moisture permeation resistance, the transparency of the synthetic resin base film is impaired, making it impossible to see through the contents.

Moreover, since the flexibility is extremely reduced, pinholes may occur.

Another example of a packaging material is a vinylidene chloride/fluororesin film which itself is moisture permeable. For applications where moisture permeation resistance is strictly required, these films must be made thicker, which poses various problems in manufacturing operations.

Furthermore, Japanese Patent Application Laid-Open No. 51-114483 attempts to improve moisture resistance by depositing aluminum on the surface of a polyester film.

However, since the aluminum vapor-deposited film is opaque, when it is used as a packaging material, the contents cannot be seen through. Moreover, since the adhesion strength between the deposited aluminum and the base film is relatively low, there is a risk that peeling may occur at the interface.

In order to improve these shortcomings of conventional packaging materials.

For example, Japanese Patent Publication No. 53-12953 proposes a transparent moisture-proof film in which silicon oxide is vapor-deposited on a plastic surface. However, since silicon oxide gradually dissolves when it comes into contact with water, a film deposited with silicon oxide may not have sufficient moisture permeation resistance.

Another drawback is that performance deteriorates over time. Unexamined Japanese Patent Publication 1973
-15208'9 discloses a polyester film on which metals, metal oxides, and silicon oxides are vapor-deposited. This vapor-deposited film can exhibit its moisture permeability resistance only when a polyester film is used as the base material.

In the field of electronics industry, there has been an increasing demand in recent years for synthetic resin bodies that are transparent and have a high degree of moisture permeation resistance for EL elements, solar cells, and the like.

(Objective of the Invention) An object of the present invention is to provide a synthetic resin body having extremely excellent moisture permeability. Another object of the present invention is to provide a transparent synthetic resin body with uniform moisture permeability resistance. Still another object of the present invention is to provide a moisture-resistant synthetic resin body with excellent transparency.

(Structure of the Invention) The present invention provides (1) that when an amorphous transparent thin film is provided on the surface of a synthetic resin base material together with a magnesium oxide thin film, moisture permeation is extremely suppressed and a synthetic resin body with excellent moisture permeability can be obtained. It was completed based on the knowledge of the inventor. Therefore, the moisture-proof transparent synthetic resin body of the present invention has at least one magnesium oxide transparent thin film and at least one amorphous transparent thin film laminated on at least one side of a transparent synthetic resin base material.

This achieves the above objective.

A transparent synthetic resin base material (
There are two examples of examples (hereinafter referred to as base materials).

Transparent synthetic resin bodies such as polyvinyl chloride, polystyrene, polyvinyl butyral, polyethylene, polypropylene, polyester, polyamide, cellophane, etc. are used. Examples of these synthetic resins are 2.

It is molded into films, plates, lenses, etc.

When using a flexible film as the base material.

Usually, the thickness is 5 to 3 ooμm, preferably 5 to 1oo, c
A film of Im is used. When depositing a metal oxide or the like onto such a film, a winding process using a cooling roll is generally required. If the thickness of the base film is too thin, wrinkles and cracks are likely to occur during this winding process. When the film thickness exceeds 300 μm, flexibility becomes poor and continuous winding becomes difficult.

A magnesium oxide transparent thin film (hereinafter referred to as "magnesium oxide thin film") or an amorphous transparent thin film (hereinafter referred to as "magnesium oxide thin film") provided on this transparent synthetic resin substrate.

(referred to as an amorphous thin film) is a vapor-deposited film. The amorphous transparent thin film referred to here is a vapor deposited film of the composition described below, and a state in which there are no crystals larger than 50 days in this vapor deposited film, and only a halo pattern is observed by electron beam diffraction. A transparent thin film.

This magnesium oxide thin film is formed by a three-reaction vapor deposition method, for example. According to vacuum evaporation method.

For example, magnesium oxide is heated with an electron gun in a vacuum chamber and evaporated to form a deposited film. According to the reactive vapor deposition method, metallic magnesium is evaporated in a vacuum chamber.

This reacts with oxygen introduced into the tank to form a deposited film of magnesium oxide. Both methods involve introducing a small amount of water in the form of steam.

The moisture permeability of the deposited film that is formed can be improved.

The composition that forms an amorphous thin film on a substrate is mainly a silicon oxide such as SiO or 5i(h).

Contains at least one of boron oxide, barium oxide, and aluminum oxide. In addition to this composition, especially silicon dioxide and boron oxide.

Contains barium oxide and/or aluminum oxide, and has a molar ratio of 2 to 4 degrees of silicon dioxide and 1 to 2 degrees of boron oxide. When the total amount of barium oxide and aluminum oxide is 0.3 to 1, the resulting transparent synthetic resin body has excellent moisture permeability. Moreover, there is no variation in its moisture permeability. When the component ratio of the composition deviates from the above values, layer separation tends to occur and moisture permeability decreases. The thin film formed when boron oxide is contained in excess has poor moisture permeability.

If the total amount of barium oxide and aluminum oxide is too small, the thin film will have poor water resistance. The amorphous transparent thin film does not need to be limited to the above-mentioned components, and the object of the present invention can be achieved even if it contains other components. However, if a large amount of an alkali metal oxide such as sodium oxide is included as one of these other components, moisture permeability will be impaired due to its hydrophilic nature. Further, the component content of the vapor-deposited thin film obtained by performing vacuum vapor deposition tends to vary.

As a method for forming the amorphous thin film on the surface of the base material, a sputtering method is preferable. When the above composition is used as a deposition source for sputtering, an amorphous thin film having substantially the same composition is formed. An amorphous thin film can also be formed by a vacuum evaporation method or an ion blating method. In the vacuum evaporation method, it is generally considered difficult to form a thin film layer of mixed substances having different vapor pressures with the same composition. However, the present inventors used an evaporation material obtained by melting the above composition in an electric furnace and vitrifying it in advance, and evaporated it using an electron gun heating method. It was confirmed. The flash evaporation method used when vacuum-depositing mixtures also allows
The moisture-permeable transparent synthetic resin body of the present invention on which a vapor-deposited film having the above-mentioned composition can be formed is formed by laminating the above-mentioned two types of vapor-deposited films sequentially or in a sandwich pattern on at least one side of a base material. For example, as shown in FIG. 1, an amorphous thin film 2 is formed on the surface of a transparent synthetic resin film base material 1.

Furthermore, a magnesium oxide thin film 3 is formed thereon. These amorphous transparent thin film 2 and magnesium oxide thin film 3 are formed as shown in FIG.

They may be formed in the reverse order to that shown in FIG. Alternatively, as shown in FIG. 3, an amorphous thin film may be arranged in the form of a two-layer sandwich between two magnesium oxide thin films 3.3. The moisture permeability resistance of the resulting synthetic resin body is dramatically improved when it has a multilayer structure of three or more layers.

When a magnesium oxide thin film is observed by means such as X-ray diffraction, high-speed electron diffraction (RHEED), and a scanning electron microscope, it is found that this thin film has a polycrystalline structure.

If only a thin magnesium oxide film is formed on the base material, water molecules will pass through between the crystals, making it impossible to obtain sufficient moisture permeability. Even if crystals exist in an amorphous thin film, the crystal grains are very small. Therefore, when this amorphous thin film and a magnesium oxide thin film are laminated, the path through which water molecules pass is effectively blocked, and a synthetic resin body with extremely excellent moisture permeability resistance can be obtained.

When a magnesium oxide thin film is formed on an amorphous thin film, the crystal grain size of the magnesium oxide thin film is much smaller than, for example, when the magnesium oxide thin film is formed on a plastic substrate. Therefore, the moisture permeability of the resulting synthetic resin body is further improved.

For example, if a thin film of magnesium oxide is formed on a polyethylene terephthalate film having a thickness of 15 μm as a base material, the moisture permeability thereof is 0.5 g/n (·24 hrs).

When an amorphous thin film is formed on the same base film, its moisture permeability becomes 1.5 g/rd·24 hrs. When a sandwich-like three-layer thin film consisting of an amorphous thin film sandwiched between magnesium oxide thin films is formed on a base material, its moisture permeability is as low as 0.06 g/rd·24 hrs.

Since the synthetic resin body of the present invention has excellent moisture permeability as described above,
As will be described later, the thickness of each transparent thin film can be made extremely thin.9 For example, even when the base material is a film, thermal deterioration of the film during vapor deposition can be minimized, which significantly increases productivity. improves.

Each thin film formed on the substrate has a thickness of 100 Å.
Above all, the total thickness is 200 to 5,000 people. If the thickness of the thin film is too thin, a uniform continuous film cannot be formed. Even if the total thickness of each thin film exceeds 5,000, the transparency of the thin film will not be impaired.

Adhesion to the base material deteriorates, causing cracks and peeling.

When the base material is a film, if the total number of thin films exceeds 5,000, curling may occur in the resulting synthetic resin body.

When the synthetic resin body of the present invention is used as a film-like packaging material, it is preferable that the synthetic resin body film has heat sealability. To produce such a synthetic resin film, for example, a heat-sealable synthetic resin film is laminated on an amorphous thin film on the film or a magnesium oxide thin film on the film.

To laminate synthetic resin films with heat-sealing properties 1. For example, a method using an adhesive (dry lamination method)
1. There is a method (extrusion lamination method) in which a synthetic resin is melt-extruded into a film and pressure-bonded to a base material. In the dry lamination method, the adhesive used differs depending on the type of the two synthetic resin films, but isocyanate-based adhesives are generally used. In extrusion lamination method.

Organic titanates and isocyanates are commonly used to create an anchor effect in transparent thin film layers.

Anchor treatment using an anchoring agent such as polyethyleneimine becomes unnecessary. Therefore, there is no need to use organic solvents as in the past. This eliminates the possibility of deteriorating the manufacturing work environment or leaving organic solvents in the product. Examples of the synthetic resin film having heat sealability include polyethylene, polypropylene, ethylene/vinyl acetate copolymer, and ethylene ionomer. Needless to say, this film has transparency.

(Example) Examples of the present invention will be described below.

Example 1 (A) Formation of amorphous thin film A mixture of silicon dioxide, boron oxide, barium oxide and aluminum oxide (molar ratio 3:1:0.67:0.33) was melted in an electric furnace and vitrified to form a molten product. I got it.

15μm thick polyethylene terephthalate (PET)
The transparent film was placed in a vacuum chamber as a base material. After the inside of the tank was evacuated to 5 Xl0-5 torr in advance, the above melt was evaporated using an electron gun heating method as an evaporation source.
The film was deposited on the substrate at a deposition rate of 1,000 people/sec. The thickness of the amorphous thin film formed was 500 mm,
When its composition was analyzed using an X&51 microanalyzer, it was found to be almost the same as the composition of the evaporation source.

(B) Formation of magnesium oxide thin film: The film on which the amorphous thin film obtained in section (A) was formed was placed in a vacuum chamber. After the inside of the tank was evacuated to 5Xl0-')-1, magnesium oxide with a purity of 99.7% was evaporated using an electron beam heating method, and the film formation rate was adjusted to about 100 people/sec using a crystal oscillation monitor. The thickness of the magnesium oxide thin film, which was vapor-deposited on the surface of the substrate under controlled conditions to obtain the moisture-permeable transparent synthetic resin body shown in Figure 1, was 50 mm.
There were 0 people.

(C) Evaluation of moisture-permeable transparent synthetic resin body: The transparency of the obtained synthetic resin body was observed. Moisture permeability JISZ-0208
Measured based on Regarding the adhesion of thin films, JIS
' The test was conducted based on D=0202. The results are shown in Table 1. In Table 1, G is amorphous thin film 2
M indicates a magnesium oxide thin film.

And among the thin films formed on the base material, the thin film directly deposited on the base material is defined as a first thin film, the thin film deposited on this first thin film is defined as a second thin film, and the thin film on the second thin film is defined as a first thin film. The third
Make it a thin film. In the transparency section, ■ indicates good transparency. In the term of adhesion of the thin film, ◎ indicates that the adhesion between the thin film and the base material is good.

1 charcoal 1 (λ) Formation of magnesium oxide thin film: The same base material as in Example 1 was prepared, and a magnesium oxide thin film was formed on this base material according to the method in Example 1 (B).

(B) Formation of amorphous thin film: An amorphous thin film was formed on the magnesium oxide thin film obtained in Section (A) according to the method in Section (A) of Example 1.

A moisture permeable transparent synthetic resin body shown in FIG. 2 was obtained.

(C) Evaluation of moisture permeable transparent synthetic resin body: Example 1 (C
) is the same as the section.

Formation of magnesium oxide thin film: The same base material as in Example 1 was prepared, and a magnesium oxide thin film was formed on this base material according to the method in Example 1 (B).

(B) Formation of amorphous thin film: An amorphous thin film was formed on the magnesium oxide thin film obtained in Section (A) according to the method in Section (A) of Example 1.

(C) Formation of magnesium oxide thin film: A magnesium oxide thin film was formed on the amorphous thin film obtained in section (B) according to the method in section (B) of Example 1.

A moisture permeable transparent synthetic resin body shown in FIG. 3 was obtained.

(D) Evaluation of moisture permeable transparent synthetic resin body: Same as Example ①.

The moisture permeability of the same base material as in Flame Comparison Example 1 was determined according to JIS Z-0208.
Measured based on The results are shown in Table 1.

Only an amorphous thin film was formed on a substrate in the same manner as in Example 1 (A). The evaluation method for the obtained moisture permeable transparent synthetic resin body was the same as in Example 1 (C).

Comparative Example 3 Only a magnesium oxide thin film was formed on a substrate in the same manner as in Example 1 (B). The evaluation method for the obtained moisture permeable transparent synthetic resin body was the same as in Example 1 (C).

Comparative coal soil (A) Formation of amorphous thin film: Same as Example 1 (A).

(B) Formation of amorphous thin film: Example on the amorphous thin film obtained in Section (A) An amorphous thin film was formed according to the method in Section (A) to obtain a moisture-resistant transparent synthetic resin body. .

(C) Evaluation of moisture permeable transparent synthetic resin body: Example 1 (C
) is the same as the section.

Comparative Example 5 (A) Formation of magnesium oxide thin film: The same base material as in Example 1 was prepared, and a magnesium oxide thin film was formed on this base material according to the method in Example 1 (B).

(B) Formation of #magnesium thin film: On the magnesium oxide thin film obtained in (A), a magnesium oxide thin film was formed according to the method in Example 1 (B), and a moisture-resistant transparent synthetic resin body was formed. Obtained.

(C) Evaluation of moisture permeable transparent synthetic resin body: Example 1 (C
) is the same as the section.

Example 4 <A) Formation of amorphous thin film: Using silicon oxide with a purity of 99.9% as an evaporation source, heating was performed using an electron beam heating method.
The procedure was the same as in Example 1 (A) except that an amorphous thin film having a thickness of 1,000 mm was formed.

(B) Formation of magnesium oxide thin film: Same as Example 1 (B).

(C) Evaluation of moisture permeable transparent synthetic resin body: Example 1 (C
) is the same as the section. The results are shown in Table 2.

Examples 4 to 6 are as follows. All the results of Comparative Examples 6 and 7 are shown in Table 2.

Example 5 (A) Formation of W film (magnesium oxide): The same base material as in Example 1 was prepared, and a magnesium oxide bacterial film was formed on this base material according to the method in Example 1 (B). .

(B) Formation of amorphous thin film: An amorphous thin film was formed on the magnesium oxide thin film obtained in Section (A) according to the method in Section (A) of Example 4.

A moisture permeable transparent synthetic resin body was obtained.

(C) Evaluation of moisture permeable transparent synthetic resin body: Example 1 (C
) is the same as the section.

Formation of magnesium oxide thin film: A substrate similar to that of Example 1 was prepared, and a magnesium oxide thin film was formed on this substrate according to the method described in Example 1 (B).

(,B) Formation of amorphous thin film = An amorphous thin film was formed on the magnesium oxide thin film obtained in Section (A) according to the method in Section (A) of Example 4.

(C) Formation of magnesium oxide thin film: On the amorphous thin film obtained in (B), a magnesium oxide thin film was formed according to the method in Example 1 (B) to form a moisture-resistant transparent synthetic resin body. I got it.

(D) Evaluation of moisture permeable transparent synthetic resin body: Example 1 (C
) is the same as the section.

Only an amorphous thin film was formed on a substrate using the same method as in Example 4 (A). The evaluation method for the obtained moisture permeable transparent synthetic resin body was the same as in Example 1 (C).

(A) Formation of amorphous thin film: Same as Example 4 (A).

(B) Formation of amorphous thin film: On the amorphous thin film obtained in (A), an amorphous thin film was formed according to the method in Example 4 (A) to obtain a moisture permeable transparent synthetic resin body. .

(Left below) Leave jf! 1N7 (A) Formation of amorphous thin film: Example 1 except that aluminum oxide with a purity of 99.9% was used as an evaporation source and an amorphous thin film with a thickness of 1000 mm was formed by heating with an electron beam heating method (A) ) is the same as the section.

(B) Formation of magnesium oxide thin film: Same as Example 1 (B).

(C) Evaluation of moisture permeable transparent synthetic resin body: Same as Example 1. The results are shown in Table 3. below.

The results of Examples 7 to 9 and Comparative Examples 8 to 9 are all shown in Table 3.

Satoru Tanko (A) Formation of magnesium oxide thin film: The same base material as in Example 1 was prepared, and a magnesium oxide thin film was formed on this base material according to the method in Example 1 (B).

(B) Formation of amorphous thin film = An amorphous thin film was formed on the magnesium oxide thin film obtained in Section (A) according to the method of Example 7 (A).

A moisture permeable transparent synthetic resin body was obtained.

(C) Evaluation of moisture permeable transparent synthetic resin body; Example 1 (C
) is the same as the section.

(A) Formation of magnesium oxide thin film: The same base material as in Example 1 was prepared, and a magnesium oxide thin film was formed on this base material according to the method in Example 1 (B).

(B) Formation of amorphous thin film: An amorphous thin film was formed on the magnesium oxide thin film obtained in Section (A) according to the method in Section (A) of Example 7.

A moisture permeable transparent synthetic resin body was obtained.

(C) Evaluation of moisture permeable transparent synthetic resin body: Example 1 (C
) is the same as the section.

North Comparison Method Only an amorphous thin film was formed on a substrate in the same manner as in Example 7 (A). The evaluation method for the obtained moisture permeable transparent synthetic resin body was the same as in Example 1 (C).

Comparative Example 9 (A) Formation of amorphous thin film: Same as Example 7 (A).

(B) Formation of amorphous thin film: An amorphous thin film was formed on the amorphous thin film obtained in Section (A) according to the method in Section (A) of Example 7.

A moisture permeable transparent synthetic resin body was obtained.

<C) Evaluation of moisture permeable transparent synthetic resin body: Example 1 (C
) is the same as the section.

(The following is a blank space) (Effects of the invention) According to the present invention, since at least one magnesium oxide transparent thin film and an amorphous transparent thin film are laminated on a transparent synthetic resin base material, The synthetic resin body has excellent moisture permeability and transparency. Moreover, there is no variation in the moisture permeability of each synthetic resin body. moreover.

Unlike the prior art, these thin films are formed regardless of the type of base material, so it is possible to obtain a moisture-permeable synthetic resin body made of a desired material and in a desired shape. When a transparent synthetic resin film is used as a base material, a synthetic resin film with excellent transparency and an unprecedentedly high degree of moisture permeation resistance can be obtained. Such synthetic resin films can be used as packaging materials for foods, medicines, chemicals, etc., which require transparency and high moisture resistance. It can also be applied to EL elements and solar cells in the electronics industry.

[Brief explanation of the drawing]

FIG. 1 is a partial sectional view showing one embodiment of the transparent synthetic resin film of the present invention, and FIGS. 2 and 3 are partial sectional views showing other embodiments, respectively. ■... Transparent synthetic resin film base material, 2... Amorphous thin film, 3... Magnesium oxide thin film. Applicant: Block Chemical Industry Co., Ltd. Figure 1 Figure 2 Figure 3

Claims (1)

[Scope of Claims] 1. A moisture-permeable transparent synthetic resin body in which at least one transparent thin film of magnesium oxide and at least one transparent amorphous film are laminated on at least one side of a transparent synthetic resin base material. 2. The synthetic resin body according to claim 1, wherein the amorphous transparent thin film is formed from a composition mainly consisting of silicon oxide. 3. The synthetic resin body according to claim 1, wherein the amorphous transparent thin film is formed from a composition mainly consisting of aluminum oxide. 4. The synthetic resin body according to claim 1, wherein the amorphous transparent thin film is formed from a composition mainly consisting of silicon dioxide, boron oxide, and barium oxide. 5. The synthetic resin body according to claim 1, wherein the amorphous transparent thin film is formed from a composition mainly consisting of silicon dioxide, boron oxide, and aluminum oxide. 6. The synthetic resin body according to claim 1, wherein the amorphous transparent thin film is formed from a composition mainly consisting of silicon dioxide, boron oxide, barium oxide, and aluminum oxide. 7. The composition forming the amorphous transparent thin film has a molar ratio of silicon dioxide of 2 to 4. Boron oxide is 1-2. And the total amount of barium oxide and aluminum oxide is 0.3~
1. The synthetic resin body according to claim 4, 5 or 6. 8. The transparent synthetic resin base material is a flexible film with a thickness of 5 to 300 μm, and the total thickness of the magnesium oxide transparent thin film and the amorphous transparent thin film is 0.02.
The synthetic resin body according to claim 1, which has a diameter of 0.5 μm. 9. The synthetic resin body according to claim 1, wherein the magnesium oxide transparent thin film and the amorphous transparent thin film are each vapor-deposited films. 10. The synthetic resin body according to claim 1, wherein the amorphous transparent thin film is sandwiched between two layers of the magnesium oxide transparent thin film.