JPH10244615A - Transparent conductive laminated body and el element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve adhesion to a luminous layer, and luminous efficiency of an El element, prevent uneven luminance, and improve durability and handling by sequentially laminating a transparent base, a transparent conductive layer, and a fluororesin layer. SOLUTION: An polyester film is preferably used for a transparent base 1, on which a transparent conductive layer 2 is laminated. The transparent conductive layer 2 is formed from indium oxide, tin monoxide, and gold by vacuum deposition, sputtering, ion plating or the like. A fluororesin layer 4 is laminated on the transparent conductive layer 2, with enhancing bond strength especially in the case of adhering to a phosphor layer. It is preferable to provide a metallic layer 3 composed of platinum and/or palladium between the transparent conductive layer 2 and the fluororesin layer 4. A forming process of the fluororesin layer 4, laminated on the transparent conductive layer 2 or the metallic layer 3, is performed by gravure coating, reverse coating or the like.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transparent conductive laminate for an electroluminescence (hereinafter abbreviated as EL) device and an EL device, which is suitable for use in a display device such as an EL device. The present invention relates to a laminate and an EL element.

[0002]

2. Description of the Related Art Conventionally, a transparent conductive laminate for an EL element has been based on a laminate comprising a transparent base material and a transparent conductive layer, and a light emitting layer, a dielectric layer and a dielectric layer are formed on the transparent conductive layer. There is known a method of sequentially forming a layer and a back electrode (metal foil or the like) (Japanese Patent Publication No. 1-81112). Further, after the light emitting layer of the laminate composed of the preformed light emitting layer, the insulating layer, and the back electrode was bonded to the transparent conductive layer by a laminating method, the whole was further covered with a transparent moisture-proof outer skin film. Things are known. Recently, the phosphor in the phosphor layer has been subjected to a moisture shielding treatment, and the EL phosphor layer, the insulator layer, and the back electrode are sequentially laminated by screen printing, and a transparent moisture-proof outer skin film is used. Inexpensive types that do not are also known.

[0003]

However, a transparent conductive laminate for an EL element which does not use a transparent moisture-proof outer cover film has insufficient durability. The present inventors have studied to obtain a transparent conductive laminate and an EL element which are an EL element not using a transparent moisture-proof outer cover film and have excellent adhesive strength and durability. That is, the present invention
For the effect of moisture entering from the outside atmosphere of the EL element,
An object of the present invention is to provide a transparent conductive laminate for an EL element having excellent adhesion to a light-emitting layer, improving luminous efficiency of the EL element, preventing occurrence of luminance unevenness, and having excellent durability and handleability. And

[0004] Further, the transparent conductive laminate for an EL element has a problem in that if the surface of the transparent conductive layer is scratched or the like, unlit lighting occurs due to disconnection, and the present invention does not cause these problems. The purpose is to facilitate handling in the processing step.

[0005]

The present invention is characterized in that a transparent substrate (A), a transparent conductive layer (B) and a fluorine-based resin layer (C) are laminated in this order. EL
E comprising a transparent conductive laminate for an element, and a metal layer (D) made of platinum and / or palladium between the transparent conductive layer (B) and the fluororesin layer (C).
This is achieved by a transparent conductive laminate for an L element and an EL element using these transparent conductive laminates.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The transparent substrate (A) used in the transparent conductive laminate of the present invention is not particularly limited, but various polymer films having excellent heat resistance are suitable. Specifically, polyester such as polyethylene terephthalate, polycarbonate, polyvinyl chloride,
A wide range of polymer films such as polyethylene, polypropylene, polyamide, cellulose acetate, and polysulfone can be mentioned, and among them, a polyester film is particularly preferable. This is because the polyester film is excellent in properties such as transparency, dimensional stability, thickness uniformity, strength, heat resistance, chemical resistance, and water resistance. Usually, the polyester film used is biaxially stretched in order to improve mechanical properties. The insulating transparent polymer film (A) is usually 50 μm to 250 μm in consideration of the function as a transparent electrode.
Having a thickness of.

The transparent conductive layer (B) to be laminated on the transparent substrate (A) is preferably a layer having conductivity and transparency when forming a thin film, for example, gold, silver, platinum and the like. , Palladium, metal such as rhodium, tin oxide, indium oxide, antimony oxide, titanium oxide, zirconium oxide, or metal oxide such as indium oxide-tin oxide, tin oxide-antimony oxide, particularly preferably indium oxide-oxide Tin and gold can be formed by a vacuum deposition method, a sputtering method, an ion plating method, or the like. The transparent conductive layer (B) may be a single layer or a multilayer of two or more layers. Although the thickness of the transparent conductive layer (B) is not particularly limited, the surface electric resistance is 1 Ω / □ to 100
0Ω / □, preferably 50Ω / □ to 500Ω / □. The total light transmittance of the transparent conductive layer (B) in the visible light region is 50% or more, and preferably 70% or more.

[0008] The fluorine-based resin layer (C) laminated on the transparent conductive layer (B) can specifically enhance the adhesive strength, particularly when bonded to a phosphor layer.
Examples of the material of the fluororesin layer (C) usable in the present invention include vinylidene fluoride resin, acrylic fluororesin, urethane fluororesin, and a mixture thereof. Acetone,
The fluororesin layer (C) can be formed by dissolving or diluting it in a solvent such as ethyl acetate or the like and coating and drying it. The thickness of the fluorine-based resin layer (C) is not particularly limited, but is preferably selected from the range of 1 nm to 500 nm in order to not impair the properties of the transparent conductive layer and to improve the adhesion with the phosphor. More preferably, 10 nm to 100
nm.

It is preferable to further provide a metal layer (D) made of platinum and / or palladium between the transparent conductive layer (B) and the fluororesin layer (C). The metal layer (D) can further improve the adhesion between the layers (B) and (C). The thickness of the metal layer (D) is not particularly limited, but is preferably in the range of 0.3 nm to 3 nm, more preferably in the range of 0.3 nm to 1.5 nm without impairing the transparency. The metal layer (D) is formed by the same vacuum deposition method, sputtering method, ion plating method or the like as the transparent conductive layer (B).

As a method of forming the fluororesin layer (C) laminated on the transparent conductive layer (B) or the metal layer (D), for example, a known coating method such as a gravure coating method or a reverse coating method is used. It can be done by a method.

Thus, the transparent conductive laminate for an EL element obtained by the present invention is not limited to a touch panel substrate, an antistatic substrate, an electrostatic shield substrate, etc., based on the EL element because of its excellent adhesiveness and surface protection. Can be widely used.

An EL element can be obtained from the transparent conductive laminate of the present invention by a conventional method. For example, a fluorine resin, an organic solvent such as methyl ethyl ketone, barium titanate, etc. are mixed on an aluminum foil, screen printed, heated and dried by a far-infrared heater, and then a fluorine resin binder, an organic solvent, and fluorescent light emission. The body is mixed, the aluminum foil is insulated, screen printed, heated and dried with a far-infrared heater, and then the fluorinated layer of the aluminum foil / insulator layer / luminescent layer and the transparent conductive laminate The EL element can be obtained by press-bonding and laminating a layer coated with a resin by a press method.

[0013]

EXAMPLES The present invention will be described below with reference to examples. The characteristic values in the examples are measured by the following methods.

(1) Surface electric resistance value A sample cut to a width of 35 mm is placed on a rubber sheet having a rubber hardness (according to JIS K6301-1975) of about 60,
A measuring electrode having a 2 mm thick palladium plate set at an interval of 35 mm is placed at a position orthogonal to the sample, a load of 3 kg is applied, and the resistance between the terminals is measured using a digital tester (VOAC707 manufactured by Iwasaki Communication Equipment). Was read directly.

(2) Light transmittance The total light transmittance in the visible light region was measured using a haze computer HGM-2DP type manufactured by Suga Test Instruments Co., Ltd.

(3) Adhesive force Adhesive force at 180 ° peel was measured using a Tensilon UCT-100 manufactured by A & D Co. at a peeling speed of 50 mm / min at a sample width of 15 mm × length of 100 mm.

(4) Durability In an atmosphere of 30.degree.
The appearance change after continuous lighting at 500 Hz for 500 hours was visually observed.

Examples 1 to 3 and Comparative Examples 1 to 2 Biaxially stretched polyethylene terephthalate film (Lumirror, Toray Industries, Inc., thickness 188 μm, visible light transmittance 8)
8%) Indium tin oxide having a composition of In ₂ O ₃ / SnO ₂ = 90/10 was adhered to the substrate by a sputtering method, and a transparent conductive layer was laminated to obtain a transparent conductive film. Sputtering is performed at a vacuum of 10 ^-4 Torr with Ar / O ₂
The test was performed with the introduction of a mixed gas. The deposited film thickness was 50 nm. The transparent conductive film thus obtained exhibited a surface electric resistance value of 200Ω / □ and a visible light transmittance of 81%.

Next, (1) a vinylidene fluoride resin "Floren" Cl-25 (manufactured by Nippon Synthetic Rubber Co., Ltd.) was diluted to 1% with ethyl acetate on the transparent conductive layer of the obtained transparent conductive film. (2) Acrylic fluororesin of MFA-7 (Matsumoto Yushi Seiyaku Co., Ltd.)
% And a paint obtained by diluting (3) a urethane-based fluororesin of MFU-1 (Matsumoto Yushi Seiyaku Co., Ltd.) to 1% with methyl isobutyl ketone by gravure coating method. Coating and lamination were performed at a temperature of 2 ° C. for 2 minutes to obtain transparent conductive laminates (1), (2) and (3), respectively. The coating thickness of these fluororesins is 50n
m. For comparison, on the transparent conductive layer of the obtained transparent conductive film, (4) cyanoethyl pullulan having a high dielectric constant (Cyanoresin CR- manufactured by Shin-Etsu Chemical Co., Ltd.)
Similarly, a coating obtained by diluting S) to 1% with a mixed solvent of dimethylformamide / acetone = 1/1 is applied and laminated by a gravure coating method at 120 ° C. for 2 minutes to obtain a transparent conductive laminate (4). Was. This coating thickness is also 50nm
Met. The thus obtained transparent conductive laminates (1), (2), (3) and (4) all had a surface electric resistance of 250Ω / □ and a visible light transmittance of 83%.

Next, 30 parts of a fluorinated resin, 40 parts of an organic solvent methyl ethyl ketone, and 30 parts of barium titanate were mixed on 100 μm of an aluminum foil, screen-printed, and dried by heating at 120 ° C. for 3 minutes using a far-infrared heater. . Next, 30 parts of a fluorinated resin binder, 40 parts of an organic solvent methyl ethyl ketone, and 30 parts of a fluorescent material were mixed, and aluminum foil was insulated and screen-printed. did. Next, the luminous layer of the above-mentioned aluminum foil / insulator layer / luminous layer and the fluororesin-coated layer of each transparent conductive laminate were pressed at 150 ° C./3 minutes, 50 kg / cm ^2. EL)
Devices were obtained respectively.

Transparent conductive laminates (1), (2), (3)
Table 1 shows the results of measuring the adhesive strength and the durability of the EL device obtained from (4) and the EL device using the transparent conductive film as it is as the transparent conductive laminate.

[0022]

[Table 1]

Example 4, Comparative Example 3 Biaxially stretched polyethylene terephthalate film (Lumirror, Toray Industries, Ltd., thickness 188 μm, visible light transmittance 8)
8%) Indium tin oxide having a composition of In ₂ O ₃ / SnO ₂ = 90/10 was applied to the substrate by a sputtering method. Sputtering A at vacuum degree 10 ^-4 Torr
The test was performed under the introduction of an r / O ₂ mixed gas. Adhesion film thickness is 50
nm. The transparent conductive film thus obtained had a surface electric resistance of 200Ω / □ and a visible light transmittance of 81%.
showed that. Next, palladium was deposited on the obtained transparent conductive layer by a sputtering method. Sputtering was performed at a degree of vacuum of 10 ^-4 Torr under the introduction of Ar gas.
The thickness of the deposited film was 1 nm. The transparent conductive film thus obtained exhibited a surface electric resistance value of 210 Ω / □ and a visible light transmittance of 80%.

Next, a coating material obtained by diluting a vinylidene fluoride resin of Florene Cl-25 (manufactured by Nippon Synthetic Rubber Co., Ltd.) to 1% with ethyl acetate on the obtained transparent conductive layer by a gravure coating method. Coating and lamination were performed at 120 ° C./2 minutes. The coating thickness of this fluororesin is 50 nm
Met. The transparent conductive laminate thus obtained is 24
0 Ω / □, visible light transmittance 83%.

Next, 30 parts of a fluorinated resin, 40 parts of an organic solvent methyl ethyl ketone, and 30 parts of barium titanate were mixed on an aluminum foil of 100 μm, screen-printed, and dried by heating at 120 ° C. for 3 minutes using a far-infrared heater. . Next, 30 parts of a fluorinated resin binder, 40 parts of an organic solvent methyl ethyl ketone, and 30 parts of a fluorescent material were mixed, and aluminum foil was insulated and screen-printed. did. Next, the luminous body layer of the above-mentioned aluminum foil / insulator layer / luminous body layer and the layer coated with the fluororesin of the transparent conductive laminate were pressed by the press method (1).
The EL element was obtained by pressure bonding at 50 ° C./3 minutes at 50 kg / cm ² ).

For comparison, a laminate having a PET / ITO / Pd laminate structure and an aluminum foil / insulator layer / light-emitting layer, which is a process of forming the transparent conductive laminate, were subjected to the same pressing. The EL element was obtained by pressure bonding and lamination by the method (150 ° C./3 minutes, 50 kg / cm ² ).

Table 2 shows the results of measuring the adhesive strength of these EL devices.

[0028]

[Table 2]

[0029]

According to the present invention, a transparent conductive laminate and an EL element having excellent adhesive strength and durability can be obtained. As a result, it has excellent adhesion to the luminescent layer against the influence of moisture entering from the external atmosphere of the EL element, improves the luminous efficiency of the EL element, prevents luminance unevenness, and has excellent durability and handleability. The transparent conductive laminated body for EL elements which has this can be obtained.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of an EL device obtained in Example 1.

FIG. 2 is a schematic cross-sectional view of the EL device obtained in Example 4.

[Explanation of symbols]

 1: Transparent substrate 2: Transparent conductive layer 3: Metal layer 4: Fluorine resin layer 5: Light emitting layer 6: Insulating layer 7: Back electrode layer

Claims (3)

[Claims] 1. A transparent conductive laminate for an electroluminescent element, wherein a transparent base material (A), a transparent conductive layer (B) and a fluororesin layer (C) are laminated in this order. body. 2. A transparent conductive layer (B) and a fluororesin layer (C).
2. The transparent conductive laminate according to claim 1, further comprising a metal layer (D) made of platinum and / or palladium. 3. An electroluminescent device using the transparent conductive laminate according to claim 1.