JPH06179962A - Gas barrier transparent electrode film - Google Patents

Abstract

PURPOSE:To provide a transparent electrode film suitable for the application to a liquid crystal display element necessary to avoid steam or oxygen and having excellent transparency, flexibility, wear resistance and gas barrier property. CONSTITUTION:The gas barrier transparent electrode film is obtained by adequately laminating a silicon oxide layer 2 formed by plasma CVD method by using at least a gaseous organic silicon compound and oxygen as raw materials and a transparent electroconductive layer 3 on a high polymer film substrate 1 such as polyether sulfone or ether etherketone and by laminating a silicone resin layer 4 on the outside of the silicon oxide layer.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a gas barrier conductive laminate using a polymer film as a base material. More specifically, it has transparency in the visible light region, and has extremely low transmittance for gases such as oxygen and water vapor, and
A gas barrier transparent electrode for a conductive film having excellent weather resistance, chemical resistance and abrasion resistance, which is suitable for application to a liquid crystal display device in which water vapor, oxygen and other harmful gases must be avoided. Regarding film.

[0002]

2. Description of the Related Art Conventionally, glass has been used as a base material for transparent conductors for liquid crystal displays, but in recent years, it has been lightweight, easy to increase in area, unbreakable, and excellent in workability. It has been proposed to use a transparent conductive film having the property of being present in an electrode. However, it has been found that when a conductive film is used, water vapor or oxygen that permeates the film causes performance deterioration of the liquid crystal element. In order to solve such a problem, it has become clear that it is necessary to impart a gas barrier property to the film substrate. Therefore, the present inventors have studied to form a transparent gas barrier layer of silicon oxide on the conductive film by the plasma chemical vapor deposition method (Japanese Patent Application No. Hei 04 (1998)).
-213162). That is, specifically, on a polymer film, at least a gas of an organosilicon compound and oxygen are introduced into a vacuum container to generate a high frequency glow discharge,
A layer of silicon oxide is formed on a polymer film at a temperature of 80 ° C. or lower, and a transparent conductive layer is further formed by a sputtering method. In this case, assuming that the polymer film is A, the transparent conductive layer is B, and the silicon oxide layer is C, CAB, CAC
A configuration such as B can be considered.

[0003]

However, the present inventors have found that the transparent electrode film having the above-mentioned structure is cut,
During the secondary processing such as bending and adhesion with other materials, we encountered an unexpected problem that some of the processed films had a markedly reduced gas barrier property.
Therefore, the inventors of the present invention have made earnest investigations into the cause of such a problem, and have found the fact that various tools and jigs that come into contact with the film surface during processing cause defects on the film surface. In order to solve such a problem, the inventors of the present invention have conducted extensive studies, and as a result, at least a transparent conductive film obtained by laminating a transparent conductive layer and a silicon oxide layer on a transparent polymer film substrate as appropriate. The present invention has been accomplished by finding a transparent electrode film having a silicon resin layer laminated on one surface.

[0004]

That is, according to the present invention, a silicon resin layer is further laminated on at least one surface of a transparent conductive film obtained by laminating a transparent conductive layer and a silicon oxide layer on a transparent polymer film substrate. The gas barrier transparent electrode film thus obtained is also preferable, and the transparent polymer film substrate is preferably a gas barrier transparent electrode film which is a polyether sulfone, and preferably the transparent polymer film substrate. Is a polyether ether ketone gas barrier transparent electrode film, and preferably a polymer film (A), a transparent conductive layer (B), a silicon oxide layer (C) and a silicon resin layer (D).
Is a gas barrier transparent electrode film in which DCAB or DCACB are laminated in this order, and preferably, the silicon oxide layer is formed by a low pressure plasma chemical vapor deposition method using at least an organosilicon compound gas and oxygen. It is a gas barrier transparent electrode film produced, and preferably, the transparent conductive layer is a gas barrier transparent electrode film produced by a sputtering method, and the oxygen permeability at 23 ° C. is preferably 0. .1 cc / m ² /
Water vapor permeability at 24 hours / 1 atm or less and 38 ° C. 90% relative humidity is 0.2 g / m 2.
Gas barrier transparent electrode film according to the which one of claims 1 to 6 ² / 24hour less, it is an gist.

In the present invention, the polymer film as the base material is not particularly limited, but it is desirable that it is transparent, has a high glass transition temperature, and has a low hygroscopicity, such as polyester, polyether sulfone and poly. Examples thereof include ether ether ketone, polycarbonate, and polyolefin film, and particularly, polyether sulfone and polyether ether ketone are preferable. The thickness of the polymer film is preferably 50 to 500 μm, but is not necessarily limited to this range.

The silicon oxide layer to be laminated on the polymer film substrate used in the present invention can be produced by a physical vapor deposition method, a chemical vapor deposition method, a wet method or the like. Specifically, in the physical vapor deposition method,
There are a vacuum vapor deposition method, an ion plating method, a sputtering method, and the like. As the chemical vapor deposition method, a thermal CVD method, a photo CVD method,
There is a plasma CVD method and the like, and a wet method includes a sol gel method and the like. However, in the present invention, since the base material is a polymer film, it is desirable to form the film at a low temperature, and a physical vapor deposition method or a plasma CVD method is preferable. Specifically, a film formation method by the plasma CVD method will be described.
It is preferable to form a silicon oxide layer on the polymer film by introducing it into a vacuum container to generate high-frequency discharge. It is also possible to use a rare gas such as helium when introducing the organosilicon compound gas. In the vacuum deposition method,
A raw material of silicon dioxide or silicon monoxide is evaporated by resistance heating or electron beam heating to deposit a film on the polymer film.
In the sputtering method, a silicon dioxide target is sputtered with argon to deposit a film on the polymer film. The thickness of the silicon oxide layer may be in the range that does not impair the transparency while maintaining the gas barrier property, and specifically, it is 20 to 5
00 nm is preferable, and more preferably 30 to 300 nm.
And more preferably 50 to 200 nm. Further, if the thickness is the same, it is more preferable to provide a silicon oxide layer on both surfaces. That is, it is more preferable to provide a 100 nm layer on both sides than to provide a 200 nm layer on one side.

The silicon oxide may contain trace amounts of iron, nickel, chromium, titanium, magnesium, aluminum, indium, zinc, tin, antimony, tungsten, molybdenum, copper and the like. Further, carbon or fluorine may be appropriately contained for the purpose of improving the flexibility of the film. The film thickness can be measured by stylus roughness meter, repetitive reflection interferometer, microbalance, crystal oscillator method, etc. Suitable to get. In addition, there is also a method in which the conditions for film formation are determined in advance, the film is formed on a test substrate, the relationship between the film formation time and the film thickness is investigated, and then the film thickness is controlled by the film formation time.

As the transparent conductive film, 1) single metal or alloy thin film layer of gold, silver, copper, aluminum, palladium, etc. 2) compound semiconductor such as tin oxide, indium oxide, zinc oxide, copper iodide 3) 1) above A laminated film in which (2) and (2) are combined is known. The transparent conductive film can be prepared by a physical vapor deposition method or a wet film forming method. As the physical vapor deposition method, a vacuum vapor deposition method, a sputtering method, an ion plating method, an activation reaction vapor deposition method, or the like can be used. A sol-gel method or the like is known as a wet film forming method. The thickness of the transparent conductive layer may be in the range where sufficient conductivity can be obtained as long as the transparency is not impaired, and the thickness is 30 nm to 50 nm.
The range of 0 nm is desirable, and more desirably 50 nm to 3
The range is 00 nm.

The composition of the silicon oxide layer and the transparent conductive layer is X.
It can be analyzed by using line photoelectron spectroscopy, X-ray microanalysis, Auger electron spectroscopy, Rutherford backscattering, and the like. For example, when the Rutherford backscattering method is used, the sample film is placed in a vacuum vessel, α particles accelerated to 1 to 4 MeV are irradiated from the sample surface, and the energy of backscattered ions is analyzed. As a result, the composition in the depth direction of the film and the uniformity of the composition can be investigated. Gold or the like may be appropriately vapor-deposited on the surface to prevent charging of the surface layer. Also, when performing analysis by Auger electron spectroscopy, the specimen is placed in an ultrahigh vacuum container, and the surface of the specimen is irradiated with an electron beam accelerated to 1 to 10 keV,
The composition can be investigated by detecting Auger electrons emitted at that time. In this case, since the electric resistance of the test piece is high, it is preferable that the current of the primary electron beam is suppressed to 10 pA or less and the energy is also set to 2 keV or less so that the influence of charging is not exerted. X-ray photoelectron spectroscopy using X-rays instead of electron beams is advantageous in that it is less susceptible to charging than Auger electron spectroscopy. Further, in X-ray photoelectron spectroscopy, since information on the bonding state of silicon can be obtained from the chemical shift of silicon, it is possible to investigate the concentration of silicon oxide on the polymer surface. When forming a silicon oxide layer or a transparent conductive layer on a polymer substrate, as a pretreatment of the substrate, corona discharge treatment, plasma treatment,
Glow discharge treatment, reverse sputtering treatment, surface roughening treatment, chemical treatment and the like, and known undercoating can be appropriately performed. The present invention is a transparent conductive film obtained by laminating a transparent conductive layer and a silicon oxide layer thus formed on a transparent polymer film substrate, wherein a silicon resin layer is further formed and laminated on at least one surface thereof. Is.

For the formation of the silicon resin layer, a known wet type thin film forming method can be used. In particular,
Examples thereof include bar coat, roll coat, spin coat, reverse roll coat and dip coat. Examples of the silicone resin that can be used include pure silicone resin, modifying silicone, silicone alkyd, silicone epoxy, silicone acryl, silicone polyester and the like. More specifically, some methods for obtaining a silicone resin layer will be described below. A linear polymer is used as a main component and crosslinked at room temperature to obtain an elastic film. As the linear polymer, there are a solvent type and a water-soluble type. In both types, a resin layer is obtained by coating the film at a solution stage with a coater and curing at room temperature. As a concrete example of a silicone resin that is cured at room temperature to become an elastic body, polydiorganosiloxane whose both ends are clogged with silanol groups is referred to as an acetoxy group, an alkoxy group, or a dialkylketoxime group bonded to a silicon atom. A polyorganosiloxane composition using an organic silicon compound having a hydrolyzable group such as a dialkylamino group, a dialkylaminoxy group and an N-methylamide group as a crosslinking agent. Water is added to the alkyltrialkoxylanes for hydrolysis, and a water-soluble carboxylic acid is added to obtain a solution of the hydrolyzed partial condensate. Then, a curing catalyst, a surfactant, and an additive for adjusting the solution are added to the solution. In addition to the above, a coater is used to coat the film surface and cure at room temperature. The film surface is coated with a solution of a commercially available polyfunctional silicone-based silicone resin in an alcohol solvent (eg, Toshiba Silicon Tosgard 510), dried at room temperature, and then heat-treated at 120 ° C. for 3 hours. What to do. After adjusting the viscosity of a commercially available silicone rubber resin solution (for example, Rhodsil RTV-573) with an appropriate solvent,
Examples thereof include those coated on a film with a coater and cured at room temperature.

The thickness of the silicone resin layer is not particularly limited, but from the viewpoint of its effect and easy handling, it is 0.5 to 50 μm, preferably 1 to 10 μm. The preferred embodiment of the present invention is shown in the drawings. When the polymer film (A), the transparent conductive layer (B), the silicon oxide layer (C) and the silicon resin layer (D) are indicated, FIG. 1 shows that these are laminated in the order of DCACB,
FIG. 2 shows a gas-barrier transparent electrode film laminated in the order of DCAB.

The gas barrier transparent electrode film of the present invention originally has an oxygen permeability of 0.1 cc at 23 ° C.
/ M ² / 24hour / 1 atm or less, and the water vapor permeability at 38 ° C. and 90% relative humidity is
0.2g / m ² / 24hour but is extremely high gas barrier properties such that the degree or less, this value does not decrease little be added to processing operations as is also shown in the following examples Should be noted.

[0013]

EXAMPLES The present invention will be described below based on Examples and Comparative Examples. (Example 1) A parallel plate using tetramethyldisiloxane (hereinafter abbreviated as TMDSO) having helium as a carrier gas and oxygen as source gases on both surfaces of a polyether sulfone (hereinafter abbreviated as PES) film having a thickness of 50 μm 13. By plasma CVD apparatus having die electrode
Plasma discharge was generated at a high frequency of 56 MHz to form a 100-nm-thick silicon oxide layer under the conditions shown in Table 1.
On one surface of the film, a transparent conductive layer containing indium oxide as a main component was formed to a thickness of 50 nm by a sputtering method under the conditions shown in Table 2. Furthermore, after applying a solution of an alcohol solvent of silicon resin (Toss Guard 510 made by Toshiba Silicone) on the surface opposite to the surface on which the transparent conductive layer is formed by a spin coater,
Heat treatment was performed at 120 ° C. for 3 hours to form a silicon resin layer having a thickness of 5 μm.

[0014]

[Table 1]

[0015]

[Table 2]

After the film is obtained by such a method, a Taber abrasion test is performed on the surface coated with the silicone resin according to ASTM D1044-73, and the abrasion wheel C is used.
S10, a weight of 500 g, and a rotation speed of 60 rpm were used. Measure turbidity after Taber test according to ASTM D1003-
61, and measure oxygen transmission rate according to ASTM D1.
It carried out according to 434-75. Table 3 shows the turbidity and oxygen permeability test results.

[0017]

[Table 3]

EXAMPLE 2 Tetramethyldisiloxane (hereinafter abbreviated as TMDSO) using helium as a carrier gas and oxygen were used as source gases on both surfaces of a 50 μm thick polyether sulfone (hereinafter abbreviated as PES) film. As a result, plasma discharge was generated at a high frequency of 13.56 MHz by a plasma CVD apparatus having parallel plate electrodes, and a silicon oxide layer having a film thickness of 100 nm was formed under the conditions shown in Table 1. A transparent conductive layer containing indium oxide as a main component was formed to a thickness of 50 nm on one surface of the film by a sputtering method. Further, a solution of silicone rubber resin (Rodsil RTV-573) is formed on the surface opposite to that on which the transparent conductive layer is formed.
After adjusting the viscosity with a solvent, it was applied to the film with a reverse roll coater and cured at room temperature. After obtaining a film by such a method, the film was wound around a φ12.5 mm stainless steel round bar (material SUS304, surface finish Ra <1.6 μm) with the surface coated with silicone resin facing outward. AST to measure the oxygen transmission rate of the same specimen
According to MD 1434-75, it was performed before and after the bending test. Further, the moisture permeability was measured before and after the bending test according to ASTM E96-82. Table 4 shows the results of the oxygen permeability test and the water vapor transmission rate.

[0019]

[Table 4]

(Comparative Example 1) On both sides of a polyether sulfone (hereinafter abbreviated as PES) film having a thickness of 50 μm, tetramethyldisiloxane (hereinafter abbreviated as TMDSO) with helium as a carrier gas and oxygen were used as source gases. As a result, plasma discharge was generated at a high frequency of 13.56 MHz by a plasma CVD apparatus having parallel plate electrodes, and a silicon oxide layer having a film thickness of 100 nm was formed under the conditions shown in Table 1. A transparent conductive layer containing indium oxide as a main component was formed to a thickness of 50 nm on one surface of the film by a sputtering method. After obtaining a film by such a method, the surface of the silicon oxide layer is subjected to a Taber abrasion test according to ASTM D
According to 1044-73, wear wheel CS10, weight 500
g, rotation speed 60 rpm. The turbidity after the Taber test is measured according to ASTM D1003-61,
The oxygen transmission rate was measured according to ASTM D1434-75. Table 5 shows the turbidity and oxygen permeability test results after the Taber abrasion test.

[0021]

[Table 5]

(Comparative Example 2) A stainless steel round bar (material SUS30) having a diameter of 12.5 mm with the surface of the silicon oxide layer of the specimen manufactured under the same conditions as used in Comparative Example 1 outside.
4. A bending test was performed by wrapping the film around the surface finish Ra <1.6 μm). The oxygen permeability test before and after the bending test was performed according to ASTM D1434-75. In addition, the moisture vapor transmission test is ASTM E96-82.
It was carried out according to. Table 6 shows the results of oxygen permeability and moisture permeability test before and after the bending test.

[0023]

[Table 6]

[0024]

As shown in the examples and comparative examples, the gas barrier transparent electrode film provided with the silicon resin layer according to the present invention shows almost no decrease in oxygen permeability and water vapor permeability even when processed. It can be seen that it exhibits remarkably excellent wear resistance and bending properties. On the other hand, in the case of the comparative example, the oxygen permeation rate and the water vapor permeation rate during the processing are drastically decreased during the processing as compared with those before the processing, and the film is finished. That is, according to the present invention, there is provided a transparent conductive film which is particularly suitable as an electrode for liquid crystal display and does not deteriorate in gas barrier performance during secondary processing.

[Brief description of drawings]

FIG. 1 is a structural diagram of a gas barrier transparent electrode film of the present invention.

FIG. 2 is a structural diagram of a gas barrier transparent electrode film of the present invention.

[Explanation of symbols]

 1 Transparent Polymer Film Base Material 2 Silicon Oxide Layer 3 Transparent Conductive Layer 4 Silicon Resin Layer

Claims (7)

[Claims] 1. A gas-barrier transparent electrode film comprising a transparent conductive film, which comprises a transparent conductive film and a silicon oxide layer laminated on a transparent polymer film substrate, and a silicon resin layer further laminated on at least one surface of the transparent conductive film. 2. The gas barrier transparent electrode film according to claim 1, wherein the transparent polymer film substrate is polyether sulfone. 3. The gas barrier transparent electrode film according to claim 1, wherein the transparent polymer film substrate is polyetheretherketone. 4. The polymer film (A), the transparent conductive layer (B), the silicon oxide layer (C), and the silicon resin layer (D),
The gas barrier transparent electrode film according to claim 1, wherein DCAB or DCACB are laminated in this order. 5. The gas barrier transparent electrode film according to claim 1, wherein the silicon oxide layer is formed by a low pressure plasma chemical vapor deposition method using at least an organosilicon compound gas and oxygen. . 6. The gas barrier transparent electrode film according to claim 1, wherein the transparent conductive layer is formed by a sputtering method. 7. The oxygen permeability at 23 ° C. is 0.1 c
c / m ² / 24hour / 1 atm or less, and the water vapor permeability at 38 ° C. and 90% relative humidity is
It is 0.2g / m < ² > / 24hour or less.
A gas barrier transparent electrode film according to any one of 1.