JPH04296381A - Tacky agent for sealing el panel and organic dispersion type el panel using the same tacky agent - Google Patents

Abstract

PURPOSE:To obtain a tacky agent having excellent hygroscopicity as a laminating agent for moistureproof films of organic dispersion type EL panels by mixing a specific amount of an inorganic hygroscopic agent into a tacky substance. CONSTITUTION:The objective tacky agent is obtained by mixing (B) 1-50vol.% inorganic hygroscopic agent composed of zeolite, silica gel, activated alumina, CaO, BaO, etc., (especially preferably the zeolite) into (A) a tacky substance such as preferably an alpha-olefinic resin or polyurethane resin having water resistance, flexibility and tackiness.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to an adhesive for sealing an EL panel with excellent hygroscopicity and an organic dispersion type E using the adhesive.
Regarding the L panel.

0002

[Prior Art] As shown in FIG. 2, an organic dispersion type EL panel is sealed by sandwiching an insulating layer 5 and a fluorescent layer 4 between a back electrode 6 and a transparent electrode 3, and laminating a water replenishing film 2 on both sides. death,
Furthermore, there is a method of laminating and sealing a fluorine-based moisture-proof film 1 on the outside using, for example, a hot roll.

Organic dispersion type EL panels have a thin, lightweight and flexible structure and emit light uniformly. However, the lifespan is said to be short because the brightness of the phosphor is significantly degraded by moisture. Therefore, it is necessary to prevent moisture from entering the interior, but as a conventional moisture-proofing measure, a fluorine-based moisture-proof film layer is provided on the outermost side of the panel, and a water-replenishing film layer is placed on the inside of the film through an adhesive 8. The outermost layer provides sufficient moisture protection, and the water replenishment layer compensates for even the slightest amount of moisture that may have entered. In other words, the fluorine-based moisture-proof film has sufficient moisture-proof ability,
Since the nylon film generally used for the water replenishment film has high hygroscopicity, the film layer has sufficient moisture-proofing ability. Furthermore, to specifically explain the structure of the moisture-proof film and the water replenishing film with reference to FIG. 2, there is an adhesive layer 8 between the moisture-proof film and the water replenishing film. Further, an adhesive 8 is used to attach the moisture-proof film around the panel. Overall, the weak point for moisture intrusion is the bonded terminals that are exposed to the surrounding area.
There is a problem that moisture enters from the adhesive layer 8.

[0004] This adhesive is used to bond fluorine-based moisture-proof films because it is difficult to bond two fluorine-based moisture-proof films to each other, but moisture intrusion from the edges of the adhesive layer does not stop, causing deterioration of the phosphor. progresses and shortens lifespan.

[0005]

The problem to be solved is that the adhesive used for the bonded portion of the moisture-proof film has moisture permeability, and it is necessary to improve this. An object of the present invention is to provide an adhesive having excellent hygroscopicity for laminating a moisture-proof film of an organic dispersion type EL panel.

[0006]

[Means for Solving the Problems] In order to achieve the above object, the present invention provides hygroscopicity by adding an inorganic hygroscopic agent to an adhesive substance in an amount of 1 to 50% by volume for laminating a moisture-proof film. An excellent adhesive was obtained. The adhesive substances used are water resistant, such as α-olefin resin and polyurethane resin.
A material having flexibility and adhesive properties is preferable. Inorganic moisture absorbers are
Zeolite, silica gel, activated alumina, CaO, Ba
An inorganic substance that absorbs water such as O is used, and zeolite is particularly preferable because it has a large adsorption amount. This moisture absorbent is mixed in an amount of 1 to 50% by volume based on the adhesive substance. If it is less than 1% by volume, the water absorption effect will be small. Furthermore, if the amount exceeds 50% by volume, the adhesive loses its adhesive strength.

[0007]

[Operation] Even if moisture enters through the bonded edges of the moisture-proof film, the inorganic moisture absorbent absorbs the moisture and stops moisture permeation. Therefore, the luminance deterioration of the phosphor can be suppressed, and this effect is remarkable.

[0008]

[Embodiment] Next, an embodiment of the present invention will be explained with reference to FIG. A paste in which barium titanate was dispersed in cyanoethyl cellulose (high dielectric resin) was applied onto the back electrode 6 made of aluminum foil using screen printing or a coater and dried. Furthermore, a paste in which the phosphor and cyanoethyl cellulose were dispersed was applied by screen printing or a coater and dried. As the transparent conductive film 3, an ITO film was laminated with a hot roll. A nylon film was used as the water replenishment film 2 and laminated together.

The layered structure shown in FIG. 1 was formed using the above-mentioned main layer materials, and the resulting device was sealed with a moisture-proof film 1 via an adhesive 7. Adhesive 7 was prepared by mixing 25% by volume of synthetic zeolite (Type 3A, particle size 10 μm or less) into a modified olefin adhesive. This was applied to the moisture-proof film 1 to a thickness of 50 μm.

[0010] Moisture-proof film 1 is a trifluorochloroethylene film that is corona-treated on one side to improve adhesion to the adhesive.

Comparative Example A panel was prepared in the same manner as in the Example, except that no inorganic moisture absorbent was mixed into the adhesive applied to the moisture-proof film.

[0012] Table 1 shows the results of the life test of organic dispersion type EL panels obtained in Examples and Comparative Examples of the present invention. The luminance indicates the luminance when driven at 400 Hz and 100 V, and the life span indicates the time required for half of the initial luminance, and was tested at normal temperature and humidity.

[0013]

[Table 1]

[0014]

[Effects of the Invention] In the organic dispersion type EL panel, moisture enters from the peripheral edge of the joint of the moisture-proof film. As a result of the bonding adhesive of the present invention absorbing this invading moisture well, it was confirmed that the panel life was significantly extended as shown in Table 1.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of an organic dispersion type EL panel of the present invention.

FIG. 2 is a cross-sectional view of a conventional organic dispersion type EL panel.

[Explanation of symbols]

1 Moisture-proof film 2 Water replenishment film 3 Transparent conductive electrode 4. Fluorescent layer 5 Insulating layer 6 Back electrode 7. Adhesive with inorganic moisture absorbent 8 Adhesive

Claims (2)

[Claims] [Claim 1] An inorganic hygroscopic agent is added to the adhesive substance from 1 to 1%.
An organic dispersion type EL panel sealing adhesive containing 50% by volume. 2. In an organic dispersion type EL panel in which a fluorescent layer and an insulating layer are laminated between a transparent conductive electrode and a back electrode, and the outside thereof is sealed with a moisture-proof film, a claim is made for laminating and sealing the moisture-proof film. Item 1. An organic dispersion type EL panel comprising the adhesive according to item 1.