JPS60202683A - El panel - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention provides EL (Ele-ct) by applying an alternating electric field.
The present invention relates to an EL spring that emits light (luminescence), and more specifically to a thin-film KL display panel in which a matrix- or box-type thin-film KL display element is housed in an envelope.

BACKGROUND TECHNOLOGY Conventionally, for AC-operated thin-film EL devices, a high electric field (about 10 V/cm) was regularly applied to the light-emitting layer to improve dielectric strength, luminous efficiency, operational stability, etc.
0.1-1.0 WT% Mn (or Cu, At,
A three-layer structure ZnS:Mn (or ZnSθ”
Mn) EL devices have been developed, and improvements in light emitting properties have been confirmed. This thin-film KL element emits high-intensity light upon application of an alternating current electric field of several KHz, and is characterized by long life.

FIG. 1 shows the basic structure of a ZnS:Mn thin film PL device as an example of a thin film EL device.

The structure of the thin film EL element will be explained in detail based on FIG.

A transparent electrode 2 such as Y, O, T
a.

06, Am 03, Si, N,, Sin, etc.
A dielectric layer 3 is formed in an overlapping manner using a sub-lid or an electron beam evaporation method. Z on the first dielectric layer 3
nS:Mn sintered bere9. A ZnS light emitting layer 4 obtained by electron beam evaporation is formed. At this time, a Zn'S:Mn sintered pellet for vapor deposition is used in which the concentration of Mn, which is an active substance, is set to a concentration suitable for the purpose. A second dielectric layer 5 made of the same material as the first dielectric layer 3 is laminated on the ZnS light emitting layer 4, and a back electrode 6 made of At or the like is further deposited thereon to form a thin film EL. An element 7 is formed. The transparent electrode 2 and the back electrode (6) are formed into a strip shape as shown in FIG. The crossing position (shaded area in FIG. 2) corresponds to one pixel of the panel.The transparent electrode 2 and the back electrode 6 are connected to an AC power source 8, and the thin film KL element 7 is driven.

When an AC voltage is applied between the electrodes 2.6, the ZNS emits light 4
The above AC voltage is generated between the dielectric layers 3 and 5 on both sides of the ZnS layer 4. Therefore, the electric field generated in the ZnS light emitting layer 4 excites the conductor and accelerates it to obtain sufficient energy. The Mn luminescent center directly excites the Mn luminescent center, and when the excited Mn luminescent center returns to the ground state, it emits orange-yellow light. In other words, electrons accelerated in a high electric field
When the electrons of 1vln atoms entering the Zn site, which is the luminescent center in the S light emitting layer 4, are excited and fall to the ground state,
It emits strong light in a wide wavelength range with a peak of approximately 585θλ.

The thin film FiL element having the above structure is NubaseF7.
As a flat, thin display device that takes advantage of the advantages of 3D printing, it can be used as a means of displaying characters, symbols, still images, moving images, etc. on computer output display terminal equipment and various other display devices that contain characters and figures. It is effective for

However, the dielectric layer of the thin-film 1!8L element contains many pinholes and microcracks that occur during the manufacturing process, and moisture, etc. enters the ZNS light emitting layer 4 through these defects, resulting in F8L light emission loss. This results in pJH, delamination, deterioration of device characteristics, etc.

In order to solve the above problem, as shown in Fig. 3, we prevent the expansion of minute thermal damage areas that occur due to breakdown caused by imperfections peculiar to thin-film KL elements, such as pinholes, when electricity is applied. A thin-film EL spring/I/9 shown in FIG. 8 is known, which is fixed and effective for moisture protection and heat dissipation in popular environments, as well as against vibration and deflection.・This thin-film KL panel 9 is To explain based on FIG. 3, reference numeral 1 is the glass substrate shown in FIG. 1, on which transparent electrodes 2 are arranged parallel to each other in a strip shape with a constant pinch interval, and an L element 7 is formed in a thin film. . A dish-shaped rear glass plate 10 is used to house the thin film KL element 7.
is superimposed on the glass substrate l, and a thin film KL is placed in the internal gap.
Element 7 is built-in. Glass substrate 1 and back glass plate 10
The joints are sealed with an adhesive such as photocurable resin (Photopond). That is, the glass substrate 1 and the back glass plate 1
0 forms the envelope 11 for the thin film BL element 7 ]14. Inside the envelope 11, a thin film EL element 7 is placed, and an insulating protective fluid 12 for protecting the thin film EL element 7, such as silicone oil or vacuum fleece, is filled and sealed. The conditions required for the insulating protective fluid 12 include permeability into pinholes, high dielectric strength, excellent heat resistance and moisture resistance, and a thin film that does not react with the L element constituent films.
It is desirable that the material be a fluid material with a small pressure and coefficient of thermal expansion, but it is particularly required that it has permeability into pinholes, has a somewhat high dielectric strength voltage, and does not react with the films constituting the thin-film KL element.

This insulating protective fluid 12 is injected from an injection hole 18 provided in the rear glass plate 10. Further, one end of the lead terminal portions of the transparent electrode 2 and the back electrode 6 of the thin film PL element 7 extends onto the glass substrate 1 outside the envelope 11 via the joint between the glass substrate 1 and the back glass plate 10. It is electrically connected to a drive control circuit (not shown). (Japanese Unexamined Patent Publications No. 52-72196, No. 52-72197) As described above, the thin film 1!8L panel 9 containing the envelope 11VC protective fluid 12 completely prevents moisture from entering the large sword. Thin film KL springs are highly reliable.

It has an excellent effect of dramatically improving your life.

However, even in the above configuration, since the protective fluid 12 itself contains moisture, this moisture is transferred to the thin film EL element 7.
However, there still remains the problem that the particles enter the cell and become a factor in deteriorating device characteristics. Water contained in the protective fluid 12 is removed from the envelope 11.
It is technically difficult to completely remove it before injection,
Even after the gas venting operation is performed, some moisture remains in the protective fluid 12.

Ru.

In order to deal with such problems, the protective fluid 12 is housed in the envelope 11, and a moisture absorbing material such as silica gel that comes into contact with the protective fluid 12 is housed (as disclosed in Japanese Patent Application Laid-Open No.
5-124182), it has been proposed to contain a protective fluid containing fine powder of a moisture absorber such as silica gel in the envelope 11 (Japanese Patent Laid-Open No. 56-92581).

However, when the insulating protective fluid 12 is filled and sealed in the envelope 11 as shown in FIG. During operation, when the protective fluid 12 thermally expands due to a rise in spring/l/temperature, the pressure increases due to the increase in volume, causing weak parts of the envelope 11, such as the glass substrate 1 and the rear glass plate 1. Stress is applied to the joint of the glass substrate l
Warped 1. The thin film formed on the glass substrate 1 may peel off.

Also, due to the thermal expansion of the protective fluid 12, the back glass plate lO
The protective fluid 12 may leak from the sealing part 14 of the injection hole 13. To prevent this, conventionally, as shown in FIG. 4, after sealing the injection hole 18, a gear with a recess and a Y-knob 15 are mounted on the envelope to prevent leakage of the protective fluid 12 into the recess inside the cap 15. It has been proposed to form a storage portion 16 (Japanese Patent Application Laid-Open No. 57-7086, Japanese Patent Application Publication No. 57-191991.). However, leakage of the protective fluid 2 from the sealing part 14 is not desirable in terms of moisture resistance, and conversely, when the thermally expanded protective fluid 12 contracts, the leaked protective fluid 12 is difficult to return to its original state, and the cap 15
There is also the disadvantage of inhaling the gas inside.

Therefore, it has been proposed to mix dry air bubbles into the protective fluid 12 contained in the envelope 11 (Japanese Patent Laid-Open No. 56
-50082). However, in this one yellow formation, the protective fluid 12
The problem was that the method of introducing air bubbles into the air bubbles and the control of the mixing ratio were complicated.

OBJECTS OF THE INVENTION Therefore, an object of the present invention is to provide a KL panel with a novel structure that can prevent deterioration of KL elements due to moisture in a PL panel in which EL elements are housed in an envelope.

Structure of the Invention The present invention provides a KL panel in which a KL element and an insulating protective fluid for the KL element are all housed in an envelope consisting of a translucent front substrate and a back plate. It is characterized by the arrangement of glass.

That is, according to the above configuration, the moisture and gas in the envelope are adsorbed by the porous galanus, and the EL element is prevented from deteriorating due to moisture.

The insulating protective fluid may be a liquid or paste such as silicone oil or silicone grease, or may be an inert gas such as dry nitrogen or argon. In the case of gases, the problems due to thermal expansion of the protective fluid are less serious;
In the case of liquid or paste-like substances, cavities in porous glass can be used.

Furthermore, this porous glass can be glued to the inner surface of the back plate in the form of roots, or it can be made into a powdered form and incorporated into a protective fluid such as silicone oil or silicone grease; It is also possible to make the inner surface porous and vitrified, which reduces the number of parts, simplifies assembly, and eliminates problems caused by adhesives and the like.

Example An embodiment of the present invention will be described below with reference to the drawings.

FIG. 5 shows a sectional view of the invention applied to a thin film EL display panel as shown in FIGS. The figure is the same as Figure 3 except for the following points, and is the same = U
O is given the same reference number N (4) and its explanation is omitted.

The thin film KL display spring /I/20 of this embodiment houses the thin film KL element 7 in an envelope 11 formed by J'j liquid or paste-like protective fluid 12 such as silicone grease.
i-accommodated one is characterized in that a plate-shaped porous glass 21 is fixed to the inner surface of the rear glass plate 1o.

This porous glass 21 has a porosity of 25 VOI%, a specific surface area of 200 ff+'/f, and a dry apparent specific gravity of 1. It has a high water adsorption property with a value of about .5.

This porous glass 21 is created, for example, as follows. First, iron sand (Sin, ), boric acid (H2PO4),
Using soda ash (Na1cOs) as the main raw material, Sin, -
B.

0, - Na, O-based borosilicate glass (Sin, ;70
wt%.

B2O3: 23 wt%, Na, O: 7 wt%) and processed into a plate shape. Next, heat treatment is performed at a temperature of several tens of degrees Celsius to cause phase separation. Then, separation of the entangled structure of the glass phases occurs on the order of several 10X, and the glass phase of B2O3-Na, ○Lilith and S10. The phase separates into the glass phase of lirithi. Said B, 0
3- Since the Na2O phase is soluble in acid solutions or hot water,
When acid treatment is applied, the B, 03-Na2O phase is dissolved and removed, forming a porous gas rich in Sin and components.
(Sin, component 96%) is obtained. This porous glass 21 is adhesively fixed to the inner surface of the back glass plate 10 directly or by using low melting point glass. Since such porous glass 21 is mostly composed of SiO□ components, it is chemically stable, and even if it exists in the protective fluid 12, it does not affect each other at all. As shown in the figure, attach the moisture absorber to the back glass plate 1 using epoxy thread resin, etc.
It is extremely reliable compared to those that are fixed with adhesive.

Furthermore, since the porous glass 21 has a large porosity, the surrounding n
Even if the protective fluid 12 thermally expands due to an increase in temperature by 1 degree or during high temperature storage or operation of the thin film KL spring/I/20 itself, it is absorbed by the porous force and the bubbles in the lath 21, so the protective fluid 12 No leakage occurred, and the injection hole 13 of the rear glass plate 10 was
There is no need to strictly stop the process as in JP-A-57-7086 shown in the figure. Of course, this does not preclude sealing as shown in FIG. In 1-, according to this embodiment, the area is larger than the conventional one! With the J4 structure, a thin film ZR and display panel with high reliability and long life can be obtained.

FIG. 6 shows a sectional view of a thin film ET display panel 22 according to another embodiment of the present invention. In this embodiment, a porous glass 23 in the form of fine powder is mixed with a liquid protective fluid 12 such as silicone oil, and the mixture is housed in an envelope 11.

In this embodiment as well, the same effects as in the embodiment shown in FIG. 5 can be obtained.

In the above embodiment, silicone oil is used as the insulating protective fluid, but a glue-like material such as silicone grease or a gaseous material such as dry nitrogen may also be used.

Further, in each of the above embodiments, the envelope 1 is provided in the envelope 11.
Although the case has been described in which the plate-shaped porous glass 21 and the copy powder-shaped porous glass 23 separate from the rear glass plate 10 are housed, the inner surface of the rear glass plate 10 can also be formed of porous glass. That is, porous glass becomes non-porous when reheated at an appropriate temperature, so for example, when processing a plate-shaped porous glass into a dish shape, by keeping only the outer surface side above a predetermined temperature, Only the outer surface can be made non-porous. In such a case, as shown in FIG. 5, a plate-shaped porous glass 21 may be fixed to the chamber glass plate 10, or as shown in FIG. Compared to those containing 23, the number of parts is reduced and assembly is significantly easier.Also, although the above embodiment describes a matrix-type thin-film KL display panel, The present invention can also be applied to a thin-film KL display panel for displaying images and an organic EL panel in which an organic EL element is formed on the transparent electrode 2.

Effects of the Invention As described above, the present invention provides a KL panel in which an EL element and an insulating protective fluid for the EL element are housed in an envelope consisting of a translucent front substrate and a back plate. Because porous glass is placed in the top, the porous glass's excellent moisture and glass adsorption properties protect the KL element from deterioration due to moisture and glass, creating a highly reliable and long-life EL element.
We can provide panels.

[Brief explanation of drawings]

Figure 1 is a cross-sectional view of a conventional matrix type thin film EL element.
Fig. 2 is a plan view showing the relationship between the transparent electrode and the back electrode of the EL element, Fig. 3 is a sectional view of a thin film EL display panel using the KL element, and Fig. 4 shows the injection hole of the envelope and other parts. FIG. 2 is an enlarged cross-sectional view of a main part showing the sealing structure of FIG. Figures 5 and 6 show thin film KL of different examples of mud and light.
FIG. 3 is a cross-sectional view of the display panel. 1・・・・・・・・・・・・・・・・・・Translucent front substrate (glass substrate), 7・・・・・・・・・・・・Iris・・
・・Thin film EL element, 10・・・・・・・・・・ Rear plate (rear glass plate), 11・・・・・・・・・・ Envelope, 12・・・・・・・・・... Protective fluid, 20.
22... Thin film KL display panel, 21.28...
・Porous glass.

Claims (1)

[Claims] 1. KL in an envelope consisting of a translucent front substrate and a back plate.
A P2T panel containing an element and an insulating protective fluid for the KL element, characterized in that porous glass is disposed within the envelope. 2. The EL panel according to claim 1, wherein the KL element is a thin film EL element. 3. The EL panel according to claim 2, wherein the EL element is a matrix type thin film KL display element. 4. The KL panel according to any one of claims 1 to 3, wherein the porous glass is fixed to an inner surface of a back plate. 5. The EL panel according to any one of claims 1 to 3, wherein the porous glass is in the form of a fine powder and is contained in the insulating protective fluid. 6. The KL panel according to any one of claims 1 to 3, wherein the porous glass is the inner surface of the back plate itself.