JPH038294A - Electric field light emitting element - Google Patents

Abstract

PURPOSE:To eliminate intensity irregularities and obtain high intensity by adding inorganic or organic transparent grains to one or multiple layers. CONSTITUTION:Organic or inorganic transparent grains are added to one or multiple layers among layers constituting an electric field light emitting element. In the electric field light emitting element constituted of a moisture absorbing layer 2, a transparent electrode layer 3, a phosphor layer 4, and a back electrode layer 5, for example, a fluorescent pigment is added to the phosphor quantity using a green light emitting metal as the phosphor to form the phosphor layer 4. Glass beads and glass powder are added to the phosphor layer 4, and the voltage is applied to an extracting terminal 6. Glass powder can be added to the phosphor layer 4 end other mixture layers, intensity is increased as the added quantity is increased, and the light diffusion property is improved. Intensity irregularities are eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to improving the luminance of an electroluminescent device having a luminescent layer between upper and lower electrode layers.

[Conventional technology]

Figure 2 shows the appearance of the electroluminescent device 8A. Transparent moisture-proof layer 1
43 is a polyethylene trifluoro-a ethylene film with low moisture permeability and moisture absorption, water replenishment effect ■ large nylon film, transparent fPJ polarity, ・43 is a polyethylene cryfluor terephthalate film, triacetate film, etc. with indium oxide, tin oxide, Vacuum vaporize mixtures of indium oxide and limited tin, gold, silver, copper, aluminum, palladium or platinum! Alternatively, it is often made of a 4TFF film that is transparent in the visible light region and is formed by sputtering. Phosphor/i#4 includes, for example, green-emitting ZnS:Cu powder and cyanoethyl cellulose,
This is a layer of a mixture with a hot pot resin such as cyanoether polyvinyl alcohol. Also, the back surface is made of a phosphor layer 4 and a conductive metal such as aluminum! A layer may be provided between the electrode layer 5 and the high dielectric resin containing a fraction of barium titanate and rIR-treated titanium white powder.

In order to adjust the luminescent color of the electroluminescent device exemplified above, fluorescent pigments and fluorescent dyes are added to the composition of the phosphor layer 4 so that the composite color becomes the desired luminescent color. Another method is to adjust the composite color by mixing two or more phosphors that emit light of different colors.

[The invention is about to be decided]

When adjusting the emitted light color in this way, the brightness and intensity of KL such as fluorescent pigments and fluorescent dyes decrease, and y4 degree unevenness (emission unevenness) occurs due to uneven thickness of the luminescent layer. Conventional countermeasures have been to reduce the additive amount of fluorescent pigments and fluorescent dyes and increase the dielectric constant of the phosphor layer in order to improve the FI value, but it is difficult to obtain the desired hue. Moreover, there was a problem that the lifespan was short.

Regarding brightness unevenness, a method has been proposed to increase light diffusion by forming fine unevenness on the surface of the moisture-proof film, but the effect is generally small, and on the contrary, #1 degree and the luxurious feel of the field luminescent element surface (
The disadvantage is that the transparency of the appearance is impaired.

In view of the problems described above, it is an object of the present invention to provide an electroluminescent device with less unevenness in brightness and brightness.

[Means for resolving mourning issues]

In the present invention, among the layers containing the electroluminescent elements, 1j! Alternatively, it is an electroluminescent device made by adding transparent organic particles such as glass beads, glass powder, or other inorganic materials or acrylic particles (fat, etc.) to multiple layers.

The diameter of the particles to be added is 01 to 100 μm as a spherical radius, and if it is less than 11 μm, secondary agglomeration is likely to occur, and if it is more than 100 μm, the surface roughness of the added layer will deteriorate and the characteristics such as f4 degree etc. decreases. In addition, the appropriate amount added per layer is 6 to 70% by volume, and 3 to 70% by volume.
If it is less than 70%, light diffusion will be insufficient and there will be no effect on brightness unevenness, and if it exceeds 70%, it will be difficult to mold the device.If it is not 17A or 1F, the bending strength of the light emitting device will decrease and cracks will easily occur.

The transparent particles of the present invention cannot be added to the back layer consisting of a 4-electrode metal layer and a layer consisting of a film. Transparent particles can be added to the phosphor 1 and other admixtures J- to bring about an effect.

[Effect]

According to the present invention, the light emitted from the phosphor is reflected and diffused by the added transparent particles, which has the effect of increasing light diffusion without deteriorating brightness.

〔Example〕

FIG. 1 shows an embodiment of the invention. Moisture absorption no 2, transparent BA electrode layer 3. In an electroluminescent device consisting of a phosphor layer 4 and a back electrode layer 5, the phosphor layer was formed by adding 20% of a fluorescent pigment to a phosphor fiK using green-emitting ZnS:Cu(C2) as a phosphor. In addition to this, the phosphor J- distributed above
30%, 50% of glass peas ki O, added, 1 piece of glass powder/f added to 60%, 30% added to a mixture of glass peas and crow powder, and the above-mentioned transparent σ of books without additives) Turtles of each machine, such as those with uneven surfaces! ff - Forms a light emitting element and connects the lead terminal 6
Jr) Frequency e! An applied voltage of 115 VAC was applied to the 4DOH film, and the brightness, light diffusivity, and surface smoothness were evaluated. The results are shown in Table 1.

Table 1 [Effects of the Invention] 11L added with the transparent particles of the present invention produced a light-emitting device.As is clear from the numerical values in Table 1, there is no difference in the effects of glass beads and glass powder, but when the amount of added 11L is increased. The brightness is high and the light diffusivity is improved. Due to the 7A size, results with less uneven brightness were obtained.

[Brief explanation of drawings]

FIG. 1 shows an example of the present invention, and FIG. 2 shows an example of a conventional electroluminescent device. 1...YJ skin-2...Moisture absorption layer, 3.
...transparent electrode layer, 4 ...phosphor layer,
5...Back side representative person

Claims (3)

[Claims] 1. An electroluminescent device comprising transparent inorganic or organic particles added to one or more of the layers constituting the electroluminescent device. 2. The particle size of transparent particles is 0.1 to 100 as equivalent sphere diameter.
2. The electroluminescent device according to claim 1, wherein the electroluminescent device has a particle size of 3 to 70% by volume. 3. 2. The electroluminescent device according to claim 1, wherein the transparent particles are glass beads, glass powder, or a mixture thereof.