JPS6029465A - Plastic body having moisture permeation resistance - Google Patents

Abstract

PURPOSE:To obtain a plastic body having superior moisture permeation resistance without deteriorating the transparency by forming a transparent thin film having a composition consisting of specific oxides on the surface of a transparent plastic body. CONSTITUTION:A transparent thin film of 100-5,000Angstrom thickness having a composition consisting of SiO2, B2O3 and BaO+Al2O3 in (2-4):(1-2):(0.3-1) molar ratio is formed on at least one side of a transparent and flexible plastic film of 5-300mum thickness made of PVC, polystyrene, polyvinyl butyral, polyethylene, polypropylene, cellophane or the like by vacuum deposition, ion plating, sputtering or other method. A flexible plastic body having superior moisture permeation resistance is obtd. without deteriorating the transparency.

Description

[Detailed description of the invention] The present invention relates to a synthetic resin body having moisture permeability resistance.

Conventionally, moisture-resistant materials have been used to prevent the contents from deteriorating in the packaging of foods, medicines, and chemical products, and in the electronics industry to preserve the film of EL elements. In Japanese Patent Publication No. 51-114483, aluminum is vapor-deposited on a polyester film, but if aluminum is vapor-deposited, the transparency will naturally be lost and the adhesion strength will be relatively low, so it can only be used for limited purposes. .

Further, in Japanese Patent Publication No. 5B-12953, a thin film layer of glasstic film K 81'07 is provided to maintain transparency, but the moisture permeation resistance is insufficient.

The present invention has been obtained as a result of intensive studies to solve the above-mentioned conventional drawbacks, and provides a synthetic resin body that does not impair transparency and has moisture permeability that is extremely resistant to moisture. It is something.

In the present invention, transparent synthetic resin bodies such as polyvinyl chloride, polystyrene, polyvinyl butyl, polyethylene, polyglopyrene, polyester, polyamide, cellophane, etc. are used as the transparent synthetic resin body of the base material. It is convenient for the synthetic resin body to be a highly flexible film-like body for packaging or laminating. However, the present invention is not limited to those in which the base material is a film-like body, but can be applied to synthetic resin molded products such as plate-like bodies and lens bodies, and can prevent deterioration and deterioration of synthetic resin bodies due to moisture permeation. It can be prevented.

The film-like transparent synthetic resin body has a thickness of 5 to 3
00 μm and is highly flexible, preferably 5 to 50 μm.
The thickness is 100 μm. In order to vapor-deposit an oxide composition on a film-like transparent synthetic resin body, a winding process using a cooling roll is normally required, but if the film-like transparent synthetic resin body has a thickness of less than 5 μm. If so, wrinkles and cracks are likely to occur, and if the thickness exceeds 300 μm, flexibility becomes poor and continuous winding becomes difficult.

A transparent thin film layer is formed on at least one side of the transparent synthetic resin body. The transparent thin film layer is S+OZ, B, O.

Consisting of BaO1Attos, in molar ratio (SIOz):
(BtOa): (BaO1Attos): 2-4
: 1-2:0.3-1.

One of BaO and At20S may not be substantially included.

If a large amount of an oxide of an alkali metal such as Nato is included in the above-mentioned composition of the transparent thin film layer, moisture permeability will be impaired due to its hydrophilic nature, and the composition will easily fluctuate even when vacuum evaporation is performed.

Furthermore, if the molar ratio of the transparent thin film layer is out of the above range, layer separation tends to occur and moisture permeation resistance decreases. And B
As the amount of tOa increases, the moisture permeability resistance tends to deteriorate due to its reactivity with water, and as the amount of (BaO1Attos) decreases, the water resistance tends to deteriorate.

The most preferable method for forming the above oxide composition on the surface of a transparent synthetic resin body is sputtering, and by using the sputtering target with the above composition, it is possible to form a transparent thin film layer with the same composition. can.

Further, a transparent thin film layer having the above composition can also be formed by a vacuum evaporation method or an ion blating method. In the case of vacuum evaporation, mixed substances with different vapor pressures are directly deposited.
It is said that it is difficult to form a thin film layer with a composition of . However, the present inventors have confirmed that if the above composition is melted in an electric furnace and vitrified in advance and used as an evaporation material and evaporated using an electron gun heating method, a deposited film with approximately the same composition can be obtained. did.

Further, a vapor deposited film having the above composition can also be formed by a flashier vapor deposition method which is generally used when vacuum vapor depositing a mixture.

In the present invention, the adhesion of the transparent thin film layer to the transparent synthetic resin body of the base material is good regardless of whether the vacuum evaporation method, ion blating method, or sputtering method is used.
Transparency is also good. Another feature of the present invention is that curling does not pose a major problem in a film-like transparent synthetic resin body in which a transparent thin film layer is formed by a vacuum evaporation method or the like. Compared to the conventional S i *Oy, this is
To form a transparent thin film layer by s1 vacuum evaporation method, ion blating method, or snok tsuttering method, usually 2×1
The test is carried out under a vacuum atmosphere of 0.1 orr or less, but in order to avoid deterioration of performance due to the contamination of impurities, 5X1G-
It is preferable to carry out under a vacuum atmosphere of 1 orr or less.

The thickness of the transparent thin film layer is preferably in the range of 100 to 5000 Å, more preferably in the range of 500 to 2500 Å, in order to have good flexibility and adhesion.

Even if the thickness of the transparent thin film layer exceeds 500,000 K, the transparency will not be impaired, but the curling property of the film-like transparent synthetic resin body has become a problem9, and cracks and peeling may easily occur. Furthermore, if the thickness of the transparent thin film layer is less than 100K, the film may have an island-like structure, resulting in insufficient moisture permeation resistance.

When the moisture permeable synthetic resin body of the present invention is used as a packaging body, it is desirable to impart heat sealability to it. In that case, (5if%B2O3, BaO1hLzOs)
Heat-sealability can be imparted to the moisture permeable synthetic resin body of the present invention by laminating a synthetic resin film having heat-sealability on a transparent thin film layer made of threads.

Examples of the synthetic resin film having heat-sealability include polyethylene, polypropylene, ethylene-hinyl acetate copolymer, ethylene-based ionomer, etc., and the film does not lose its transparency.

To laminate synthetic resin films having heat-sealing properties, there are a method using an adhesive (dry lamination method) and a method of melt-extruding a synthetic resin into a film and pressing it onto a base material (extrusion lamination method).

In the dry lamination method, the adhesive used varies depending on the synthetic resin film, but incyanate-based adhesives are generally used. In the extrusion lamination method, a transparent thin film layer of complex glue (1), (Pe acid) compound, (3) Since the anchoring effect is expressed, the anchor treatment using an organic titanate-based, isocyanate-based, or polyethyleneimine-based anchoring agent, which is usually performed, becomes unnecessary. Therefore, there is no need to use conventional organic solvents, and the production environment will not be degraded, nor will organic solvents remain in the product.

Examples of the present invention are shown below.

<Example 1> A mixture of oxides with a molar ratio of 5LOZ, B2O3, BaO1At to OII of 3:1:0.67:0.33 was melted in an electric furnace and vitrified to 5X Iorr.
Polyethylene Tele7 (PET) film (15μ door thickness) is heated and evaporated using an electron gun heating method under a vacuum of
A transparent thin film layer with a thickness of 100 OA was formed on top. The thickness of the transparent thin film layer was measured using a crystal oscillation type monitor. The composition of the transparent thin film layer was analyzed using a chi-ray microanalyzer and was found to be approximately the same as the composition of the initial mixture.

Adhesion d of formed transparent thin film layer JIS D0202
I checked it and it was in very good condition.

Further, the light transmittance of the film on which the transparent thin film layer was formed was approximately the same as that of the undeposited film, and the transparency was good.

Moisture permeability is JIS at 40℃ and relative humidity 90%RH.
It was measured by Z 0208 (gravimetric method using a cup) and hygrometer method, and both values were approximately the same @<Example 2> In Example 1, the thickness of the transparent thin film layer was set to 2000A.

<Example 3.4> Instead of the PET film of Example 1, a biaxially oriented polypropylene (OPP) film (25 μm thick) was used.

<Examples 5 to 8> In place of the mixture composition of Example 1, the compositions shown in the table were used to form transparent thin film layers.

<Comparative Example 1.2>') In place of the mixture composition of Example \1, a transparent thin film layer was formed using a mixture having a molar ratio composition outside the range of the present invention.

<Comparative Examples 3 and 4> SiO and S forming a conventionally known moisture-resistant transparent thin film layer
A transparent thin film layer was formed using tO,.

<Comparative Example 5> A thin film layer, which is opaque but is said to have good moisture permeability, was formed on a PET film.

Below margin ◎; Good adhesion and transparency Δ: Poor adhesion and ＼Poor ×; Transparency and above. It has excellent moisture permeability and can be used as food and drug packaging.
It can be used as a protector for EL elements.

patent applicant Sekisui Chemical Co., Ltd. Representative: Mototoshi Fujinuma

Claims (1)

[Claims] At least one side of the transparent synthetic resin body is made of SiO2, To
ss. The molar ratio of BaO1AttOs is (Sift) e
(BtOa)S(nao+Atzoa) = 2~4
A synthetic resin body having moisture permeability, characterized in that a transparent thin film layer of a composition having a ratio of: 1 to 2: 0.3 to 1 is formed. The lambda transparent synthetic resin body is a highly flexible film-like body with a thickness of 5 to 300μ, and the transparent thin film layer has a thickness of 100 to 500μ.
The synthetic resin body having moisture permeability according to claim 1, which is OA. 3. The synthetic resin body having moisture permeability resistance according to claim 1 or 2, wherein the transparent thin film layer is formed by a vacuum evaporation method, an ion blating method, or a sputtering method.