JPH086400Y2 - EL panel - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention relates to an EL (electroluminescence) panel, and more particularly to an organic binder dispersion type EL panel in which blackening of a peripheral portion during lighting is improved.

[Prior Art] Generally, in an organic binder dispersion type EL panel in which phosphor particles such as ZnS: Cu are dispersed in an organic binder to form an electroluminescent layer, in order to prevent luminance deterioration due to humidity, the moisture permeability is extremely low. A skin film made of trifluorochloroethylene resin (PCTFE) is used. Since the outer skin film has weak adhesion to trifluorochloroethylene resin (PCTFE), the outer skin film can be adhered, for example, by subjecting the film surface to sputter etching treatment, and adhesion of thermoplastic polyolefin resin It is formed by covering the agent layer, and therefore, the sealing portion of the outer film at the peripheral portion of the EL panel is adhered by the adhesive layer.

Referring to FIG. 2, generally, in a dispersion-type EL panel, an electroluminescent layer 6 and a reflective insulating layer 8 are provided between a transparent electrode 2 and a back electrode 4, and these are surrounded by water trapping layers 10 and 12. above,
A pair of outer skin films 14, 16 are laminated, and the outer skin films 14, 16 are respectively base layers 18, 20 made of trifluorochloroethylene resin, and a small amount of vinyl acetate resin or acrylic resin or the like. And an adhesive layer 22 and 24 made of a modified polyethylene resin containing
The peripheral portions of 14 and 16 are sealed to each other with adhesive layers 22 and 24.

[Problems to be solved by the present invention] However, in an EL panel sealed with a pair of outer films 14 and 16, as shown by a symbol A in FIG. Therefore, there is a problem in that moisture invades, the brightness is reduced around the light emitting surface, and the peripheral portion is blackened.

Therefore, it is an object of the present invention to provide an EL panel which has a long life by suppressing the blackening of the periphery of the light emitting surface.

[Means for Solving the Problems] The above-mentioned object is to provide a pair of water-trapping layers that surround a transparent electrode and a back electrode, and an outer skin film that is laminated on these water-trapping layers and seals the peripheral portions. In the EL panel having, a porous sheet is formed between the water catching layer on the back electrode side and the outer film.
Solved by EL panel.

Suitably, the porous sheet comprises paper or cellophane.

Further, the outer film on the back electrode side is a laminated film having an aluminum layer.

[Operation] By forming a porous sheet between the water catching layer on the back electrode side and the outer cover film, moisture that has penetrated through the melted adhesive layer in the peripheral portion of the outer cover film inside the porous sheet. Since the holes are used as ventilation holes and spread over the entire surface of the water catching layer on the back electrode side, the periphery of the phosphor screen is not deteriorated and blackened unlike the conventional case. Further, since the water capturing layer captures the water to the full extent of the water absorbing capacity over the entire surface of the water capturing layer, the deterioration of the emission brightness in the light emitting layer is delayed and a long life is realized.

Further, when the back electrode side outer film is a laminated film having an aluminum layer, conventionally, even if the back electrode side water trapping layer was provided, it did not serve to trap water, but it was porous. The sheet sufficiently fulfills the function of a water catching layer.

[Embodiment] An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a schematic sectional view of an EL panel of the present invention. In FIG. 1, the same parts as those in FIG. 2 are denoted by the same reference numerals, that is, as shown on the left side of FIG. 1, the EL panel has an electroluminescence between the transparent electrode 2 and the back electrode 4. Layer 6
And the reflective insulating layer 8 is provided, and these are surrounded by the water capturing layers 10 and 12, and the porous sheet 26 is laminated on the water capturing layer 12 on the side of the back electrode 4, and on the water capturing layer 10 and the porous sheet 26. A pair of outer skin films 14, 16 'are laminated respectively.

The outer cover film 14 has a base material layer 18 made of a trifluorochloroethylene resin and an adhesive layer 22 made of a modified resin. On the other hand, the outer film 16 ′ on the back electrode 4 side is a laminated film composed of four layers, and includes a base material layer 162 made of polyester resin, an adhesive layer 164 made of polyethylene resin, an aluminum layer 166 made of aluminum foil, and an adhesive. Tier 1
It consists of 68. To laminate such an aluminum laminated film on an EL panel, a normal heat roller is used, and it can be easily laminated.

What should be noted in this invention is the porous sheet 26 laminated on the water catching layer 12 on the back electrode 4 side. The porous sheet 26 may be formed by laminating at the time of pressure bonding or at the time of thermocompression bonding of the outer skin films 14 and 16, or the porous sheet 26 may be laminated on one surface of the water capturing layer 12 in advance. In this embodiment, the porous sheet 26 is made of moisture-proof cellophane paper 50 μm having one side subjected to moisture-proof processing, but may be made of a porous sheet such as paper or cellophane that is sufficiently dried with water. . Thickness is 10 ~ 200μm, preferably 100μm
The thickness before and after is preferable.

In the case of cellophane paper, it is necessary to use moisture-proof cellophane paper with one side being moisture-proof and to arrange so that the contact surface with the outer film 16 is the moisture-proof surface that has been moisture-proofed. An adhesive layer 22 of the outer film 14, 16 shown by
In order to diffuse the water entering from 24 over the entire surface of the water trap layer 12,
Of course.

For drying, it is sufficient to vacuum-dry paper or cellophane paper for 1 to 3 hours in advance and then stack them.

The EL panel constructed in this way is a porous sheet.
Conventional EL same as the above embodiment except that 26 is not formed
Compared to the panel, we were able to achieve 6000 hours with a long life of luminance half-life of 1000 hours.

Further, conventionally, as a result of a forced deterioration test at a humidity of 95% and a temperature of 40 ° C., blackening of the periphery of the light emitting surface appeared around 600 hours, whereas in the present example, the blackening exceeds 1000 hours. However, it did not appear, and the uneven brightness on the light emitting surface did not occur.

[Effect of the Invention] As described above, according to the present invention, by forming a porous sheet between the water catching layer on the back electrode side and the outer film, it is possible to prevent peripheral blackening on the light emitting surface, An EL panel with a long life can be provided.

[Brief description of drawings]

FIG. 1 is a schematic partial sectional view of an EL panel of one embodiment according to the present invention, and FIG. 2 is a schematic partial sectional view of a conventional EL panel similar to that of FIG. 2 ... Transparent electrode, 4 ... Back electrode, 6 ... Light emitting layer, 10,
12 ... Water catching layer, 14, 16 '... Skin film, 20', 26 ...
… Porous sheet, 164 …… Aluminum layer.

Claims (3)

[Scope of utility model registration request] 1. An EL panel having a pair of water-trapping layers surrounding a transparent electrode and a back electrode, and an outer film laminated on the water-trapping layers and having a peripheral edge sealed. An EL panel characterized in that a porous sheet is formed between a water catching layer on the back electrode side and an outer film. 2. The EL panel according to claim 1, characterized in that the porous sheet is made of paper or cellophane. 3. The EL panel according to claim 1 or 2, characterized in that the outer film on the back electrode side is a laminated film having an aluminum layer.