JP2003245996A - Transparent gas and steam barrier film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a transparent gas and steam barrier film which has both higher gas and steam barrier performance than those of a prior art and high transparency, and excellent chemical resistance. <P>SOLUTION: The transparent gas and steam barrier film is obtained by sequentially laminating a gas and steam barrier layer containing an alloy oxide containing In a Sn as main ingredients and a protective layer of an electrically insulating inorganic thin film on at least one surface of a polymer film. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a transparent film having a high gas / water vapor barrier property, which can be applied to a wide range of applications such as optical members, electronic members, general packaging members, and chemical packaging members.

[0002]

2. Description of the Related Art Conventionally, a gas / water vapor barrier film in which a thin film of a metal oxide such as aluminum oxide, magnesium oxide, or silicon oxide is formed on the surface of a plastic substrate or a film is used for an article requiring gas shielding. It is widely used for packaging and packaging applications to prevent the deterioration of foods, industrial products, pharmaceuticals, etc. In addition to packaging applications, liquid crystal display devices, solar cells, electroluminescence (E
L) Used in substrates, etc. Especially liquid crystal display elements, EL
In recent years, transparent base materials, which have been increasingly applied to devices, are required to be lighter and larger, and have a high level of reliability such as long-term reliability and flexibility in shape, and curved surface display. In response to demands, a film base material such as a transparent plastic has begun to be adopted in place of a glass substrate which is heavy and easily broken, and which is difficult to increase in area. Further, the plastic film not only meets the above-mentioned requirements but also has the advantage of being more productive and cost-effective than glass since it can be used in a roll-to-roll system. However, there is a problem that a film base material such as transparent plastic is inferior in gas / water vapor barrier property to glass. If a base material having a poor gas / water vapor barrier property is used, oxygen and water vapor permeate to deteriorate the liquid crystal in, for example, a liquid crystal cell, resulting in display defects and deterioration of display quality. In order to solve such a problem, it is known to form a metal oxide thin film on a film base material to form a gas / water vapor barrier film substrate. As a gas / water vapor barrier film used for packaging materials and liquid crystal display elements, a film obtained by vapor deposition of silicon oxide on a plastic film (Japanese Patent Publication No. 53-12953) or a film obtained by vapor deposition of aluminum oxide (Japanese Patent Laid-Open No. 58-58- No. 217344) is known, and all have a water vapor barrier property of about 1 g / m2 / day. In recent years, due to the increase in the size of liquid crystal displays and the development of high-definition displays, the gas / water vapor barrier performance of film substrates, for example, the water vapor permeability of 0.1 g / m2 / da
The demand is increasing up to about y. In order to respond to this, a film formation study by a sputtering method or a CVD method is being conducted as a means for expecting higher gas / water vapor barrier performance.

However, in recent years, the development of organic EL displays and high-definition color liquid crystal displays, which are required to have further gas / water vapor barrier properties, has progressed, and higher gas / water vapor is maintained while maintaining the transparency usable for these. Base materials having barrier properties, for example, water vapor permeability of less than 0.1 g / m2 / day have been required. Further, as a means for solving these problems, there is Japanese Patent Publication No. 09-39151. However, since the organic coat is used for the purpose of protecting the conductive barrier layer, there is a problem of short circuit between electrodes after patterning depending on the device design such as liquid crystal display and organic EL due to the pinhole of the organic coat. It was

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a transparent gas / water vapor barrier film having higher gas / water vapor barrier performance than ever before, high transparency, and excellent chemical resistance. It is in.

[0005]

Means for Solving the Problems That is, the present invention provides (1) a gas / water vapor barrier layer made of an alloy oxide containing In and Sn as a main component and an electrically insulating inorganic thin film on at least one side of a polymer film. A transparent gas / water vapor barrier film, which is obtained by sequentially laminating certain protective layers. (2) The film thickness of the gas / water vapor barrier layer is 10 nm to 20
The transparent gas / water vapor barrier film according to (1), which has a thickness of 0 nm. (3) The transparent gas / water vapor barrier film according to (1) or (2), wherein the protective layer has a film thickness of 10 nm to 500 nm. (4) The transparent gas / water vapor barrier film of (1) to (3) having a surface resistance value of 30 MΩ / sq or more. Is.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The gas / water vapor barrier film of the present invention is a known anchor coat layer typified by, for example, an epoxy acrylic resin, for enhancing adhesion between a polymer film and a gas / water vapor barrier layer. There is no problem.
Therefore, the content of the layer is, for example, protective layer / gas / water vapor barrier layer / polymer film, protective layer / gas / water vapor barrier layer / anchor coat layer / polymer film, protective layer / gas / water vapor barrier layer / anchor coat layer / Polymer film / anchor coat layer, protective layer / gas / water vapor barrier layer / polymer film / gas / water vapor barrier layer / protective layer protective layer / gas / water vapor barrier layer / anchor coat layer / polymer film / anchor coat layer / Gas / water vapor barrier layer /
A protective layer and the like are conceivable, but not limited thereto. There is no limitation on the transparent polymer film used in the present invention, but polysulfone resin, polyether sulfone resin, polycarbonate resin, polyarylate resin, polyacrylate resin, polyester resin, polyamide resin, epoxy resin, polyimide resin, polyolefin resin Etc. can be used. The total light transmittance of the transparent polymer film used in the present invention is at least 4
0% or more, preferably 80% or more is desirable. The transparent polymer film used in the present invention is a gas / water vapor barrier layer,
Prior to the formation of the protective layer, surface treatment such as degassing treatment, corona discharge treatment, and flame treatment may be performed in order to enhance the adhesion between each layer and the polymer film.

The gas / water vapor barrier layer of the present invention comprises In,
It is an alloy oxide of Sn and can be formed by vacuum vapor deposition, ion plating, sputtering or the like. In particular, an alloy oxide target of In or Sn with a density of 95% or more is used, and the thickness is 10 nm by magnetron sputtering. 200 nm, preferably 10 nm to 150
The gas / water vapor barrier layer formed to have a water vapor permeability of 0.1 g / m2 / day and an oxygen gas permeability of 0.1 cc
/ M2 / day / atm or less is good. If the thickness of the gas / water vapor barrier layer is less than the lower limit, the gas / water vapor barrier layer does not have a completely continuous structure, and the gas / water vapor barrier layer may be destroyed due to expansion and contraction of the laminated film due to temperature change. Grows larger. Further, if the thickness of the gas / water vapor barrier layer exceeds the upper limit value, the transparency is deteriorated due to coloring, and the gas / water vapor barrier property is deteriorated due to the generation of cracks due to the internal stress of the gas / water vapor barrier layer, which is not preferable. . Furthermore, in order to enhance the gas barrier property, the thickness of the gas barrier layer is preferably about 10 to 100 nm at which cracks due to internal stress do not occur.

As the protective layer covering the gas / water vapor barrier layer used in the present invention, an insulating inorganic thin film is preferable.
There is no limitation on the material of the electrically insulating inorganic thin film, but for example, an oxide or nitride containing at least one of Si, Al, Ti, Cu, Ta, Ce, etc., or an oxynitride can be used. . These protective layers can be formed by vacuum vapor deposition, ion plating, sputtering, or the like. If the thickness of the protective layer is too thick, cracks due to bending stress will occur, and if it is too thin, the film will be distributed in an island shape, and neither of them will serve as an electrically insulating protective coat layer. preferable. Furthermore, it is preferable to form the gas / water vapor barrier layer and the protective layer at the same time at the same time, because pinholes due to foreign matter can be eliminated. Specifically, unlike the conventional method, the method of forming the resin protective coating layer after forming the inorganic barrier layer is not the same process, so there is a high possibility that foreign matter may be mixed in when switching the device, but for example, two cathodes are arranged in series. By using the existing sputtering equipment to continuously form the inorganic barrier layer and the protective layer at one time, it is possible to prevent foreign substances from entering, which is a problem for liquid crystal display devices and organic EL display devices. It is possible to eliminate defects such as a short circuit of the pattern due to. Further, the transparent gas / water vapor barrier film according to the present invention has a defect caused by an alkaline solution immersion treatment such as NaOH or an acid solution immersion treatment such as HCl necessary for producing a liquid crystal display device, an organic EL display device, or the like. The problem of impairing the water vapor barrier property can be overcome by laminating the protective layer.

[0009]

[Example] <Example 1> Bifunctional epoxy acrylate (Showa High Polymer: VR-60-L) on a polyether sulfone film
AV) 25wt%, diethylene glycol 50wt%, ethyl acetate 24w
A uniform mixed solution containing t% and a silane coupling agent of 1 wt% was applied by a spin coater, heated and dried at 80 ° C. for 10 minutes, and further cured by UV irradiation to form a 2 μm anchor coat layer. Next, in a sputtering device equipped with two cathodes
The ITO target and the Si target are set, the polyether sulfone film having the resin layer is set in the vacuum chamber of the apparatus, the vacuum is evacuated to the level of 10 ^-4 Pa, and argon is used as a discharge gas at a partial pressure. 0.1Pa, oxygen partial pressure 0.005Pa
Introduced. When the atmospheric pressure became stable, discharge was started, plasma was generated on an ITO target with a relative density of 95%, and the sputtering process was started. When the process became stable, the shutter was opened and the formation of the ITO layer as a gas / water vapor barrier layer on the film was started. 90n
When the m film was deposited, the shutter was closed to complete the film formation. Then, argon was used as a discharge gas at a partial pressure of 0.1 P
Introduced a and oxygen as a reaction gas at a partial pressure of 0.01 Pa.
When the atmospheric pressure became stable, discharge on the Si target side was started, plasma was generated on the Si target, and the sputtering process was started. When the process became stable, the shutter was opened and the formation of a silicon oxide layer as a protective layer on the film was started. When the 80 nm film was deposited, the shutter was closed to complete the film formation. Atmosphere was introduced into the vacuum chamber, and the film on which the silicon oxynitride layer was formed was taken out.

Example 2 A gas / water vapor barrier film of the present invention was produced in the same manner as in Example 1 except that the anchor coat layer used in Example 1 was omitted. <Example 3> The protective layer / gas / water vapor barrier layer having the structure of Example 2 is also laminated on the back surface side of the polyethersulfone film to form a protective layer / gas / water vapor barrier layer / polymer film / gas / water vapor. A gas / water vapor barrier film of the present invention having a layer structure of barrier layer / protective layer was produced. The formation of each layer was performed in the same manner as in Example 1. <Example 4> An anchor coat layer was laminated on the back surface of Example 1 in the same manner as in Example 1. <Example 5> The protective layer / gas / water vapor barrier layer / anchor coat layer having the structure of Example 1 is also laminated on the back surface side of the polyethersulfone film to provide a protective layer / gas / water vapor barrier layer / anchor coat layer. A gas / water vapor barrier film of the present invention having a layer structure of / polymer film / anchor coat layer / gas / water vapor barrier layer / protective layer was produced. The formation of each layer was performed in the same manner as in Example 1.

<Comparative Example 1> A comparative example 1 was prepared in the same manner as in Example 1 except that the protective layer was omitted. <Comparative Example 2> The same procedure as in Example 2 was performed except that the protective layer was omitted. <Comparative Example 3> The procedure of Example 3 was repeated except that the protective layer was omitted. <Comparative Example 4> The same procedure as in Example 4 was performed except that the protective layer was omitted. <Comparative Example 5> The same procedure as in Example 5 was repeated except that the protective layer was omitted.

(Evaluation) The surface resistance of each film was measured with a bipolar parallel electrode. Water vapor permeability was measured by JIS K7129B method as gas / water vapor barrier performance. Further, the water vapor permeability after being immersed in HCl having a concentration of 1 N and a liquid temperature of 30 ° C. for 5 minutes was also measured. Regarding the light transmittance, a value at a wavelength of 400 nm was measured with a spectral transmittance meter. The results are shown in Table 1.

[0013]

[Table 1]

In the examples, good films were obtained in all items. In Comparative Example, the surface resistance was low and the film became conductive, and the gas / water vapor barrier property was deteriorated by the acid, so that it was unsuitable as a gas / water vapor barrier film for a display device.

[0015]

According to the present invention, it is possible to provide a transparent gas / water vapor barrier film having excellent transparency, gas / water vapor barrier property and durability.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) // C08L 101: 00 C08L 101: 00 F term (reference) 2H090 HA01 HB03X HB06X HC01 HD01 JA06 JB03 JC07 JD11 JD12 4F006 AA22 AA34 AA35 AA36 AA38 AA40 AB73 AB74 BA05 CA07 CA08 DA01 4F100 AA01C AA17B AA28B AD00C AK01A AK55 BA03 BA07 BA10A BA10C GB15 GB41 JB01 JD02 JD02B JD04 JD04B JG04A JG00CYY0101

Claims (4)

[Claims] 1. A polymer film having I on at least one side thereof.
A transparent gas / water vapor barrier film comprising a gas / water vapor barrier layer made of an alloy oxide containing n and Sn as main components and a protective layer which is an electrically insulating inorganic thin film, which are sequentially laminated. 2. The film thickness of the gas / water vapor barrier layer is 10 n.
The transparent gas / water vapor barrier film according to claim 1, which has a thickness of m to 200 nm. 3. The film thickness of the protective layer is 10 nm to 500 nm.
The transparent gas / water vapor barrier film according to any one of claims 1 and 2, wherein 4. A surface resistance value of 30 MΩ / sq or more.
A transparent gas / water vapor barrier film according to any one of 3 to 3.