JPH01159996A - Electroluminescence display device - Google Patents

Abstract

PURPOSE:To enhance the anti-moistening property, remove the coating process of glass frit to a spacer, and eliminate stress concentration at the bonded part by adhering the periphery of a glass sheet using a low melting point glass without using any spacer. CONSTITUTION:Two glass sheets 3, 3 are bonded at peripheries with a low melting point glass so as to have a certain gap, and a seal 4 is formed. As this seal does not use any spacer, the amount of low melting point glass increases accordingly, and it is heated at the time of bonding and wets on the glass sheets to present meniscus structure as shown in the attached illustration. This sealing with low melting point glass shall not necessarily be applied to the whole peripheral edges-the portion where electroluminescence element is encapsulate shall preferably be sealed with a glass having a lower melting point to prevent heat deterioration of the element. As no spacer is used in this manner, a process to coat frit to the spacer is no more necessary to lead to enhancement of the producibility, and forming of meniscus with the seal 4 and associate dispersion of stresses should allow the glass sheets to be made thinner to contribute to constructing in small size and light weight.

Description

[Detailed description of the invention] “Industrial Application Fields” The present invention relates to electroluminescent display devices.

[Prior Art] Since the performance of electroluminescent elements is extremely degraded by moisture, they are protected by materials with excellent moisture resistance.

Specifically, a structure in which a fluororesin film and an element are laminated, a plastic package, or a package in which two sheets of glass are bonded together with a resin and the element is sealed are used. Furthermore, as shown in FIG. 4, a low-melting glass frit 2 was applied to a spacer 1 made of metal or the like, and two sheets of glass 3 were bonded to each other via this spacer to form a package and an element was sealed 11- into this. Something has also been proposed.

However, products using fluororesin films, plastic packages, and packages made of two sheets of glass glued together with resin have insufficient moisture resistance and cannot be used in high humidity environments such as outdoors. I couldn't come.

On the other hand, packages using glass frit require a process of applying frit to the spacer, which complicates the production process and causes stress on the bonded area due to the pressure difference between the inside and outside after the element is sealed. Because of the concentration, there was a problem in that the thickness of the glass sheet could not be made thinner from the viewpoint of strength.

[Problems to be solved by the invention] The present invention solves the above-mentioned problems of the prior art.
To provide an electroluminescent display device which has excellent erasability and moisture resistance, eliminates the need to apply a glass frit to a spacer, eliminates stress concentration at an adhesive part, and allows the use of thin plate glass.

[Means for Solving the Problems] The present invention provides a display device in which an electroluminescent element is provided in the gap between two sheets of glass, and the periphery of the glass sheets is bonded. To provide an electroluminescent display device characterized in that it is formed by bonding the peripheral edge of a sheet of glass. The low melting point glass used in the present invention is one that can be bonded at a temperature lower than the transition temperature of plate glass by 1.1 degrees. This is particularly preferred in terms of workability since there is no risk of deformation of the sheet glass due to heating during bonding.

Further, in order to reduce thermal stress caused by adhesion, it is preferable that the difference in coefficient of thermal expansion between plate glass and low melting point glass is small. Room specifically? Xu! The coefficient of thermal expansion of low melting point 611 particles at 30D°C is a.

If the coefficient of thermal expansion of plate glass is a2, then 1al.

ap)'s straight line is 120x In-7/℃~10fox
Low melting point glasses in the range of 10-7/'C are preferred.

Examples of low-melting glass having such characteristics include those having the following composition. That is, in weight ji)% display, I'b0 55~75 13□0,0~15 Z000~15 SI02 1 ~25 AI203 0 ~20 J12D o ~2D (R20 is 1
120. Either one or two of Na2O and K2O
2).

On the other hand, the sheet glass used in the present invention is not particularly limited.

The following will explain based on the drawings.゛ FIG. 1 is a sectional view of a device according to the invention.

As shown in the figure, the peripheral edges of two glass plates 3.3 are adhered with low melting point glass so as to have a predetermined gap to form a sealing part 4. Since this sealing part does not use a spacer, the amount of low-melting point glass increases accordingly, which is heated during bonding, wets the sheet glass, and forms a meniscus shape as shown in the figure. It is not necessary to seal the entire periphery with such a low melting point glass, and it is preferable that the part where the electroluminescent element is sealed is sealed with glass having a lower melting point to prevent thermal deterioration of the element. 5 is an electroluminescent element.

Such a device can be manufactured as follows.

As shown in FIG. 2, a rod-shaped low melting point glass rod 6 is placed on the peripheral edge of one of the glass plates 3. The cross-sectional shape of this glass rod may be either circular or polygonal, but it is best to use one that is thicker than the intended gap between the sheets of glass for good sealing.
Two is preferable.

Specifically, it is preferable that the cross-section of the rod is a circle whose diameter is about 0.2 to 0.5 mm smaller than the gap between the glass plates. Note that the glass rods are placed on three peripheries except for one periphery that encloses electroluminescence.

Next, a holding member 7 that holds the desired gap between the glass sheets
is placed on the center of the sheet glass, and then the other plate r+J'j is placed and bonded by heating near the transition point of the low melting point jl'7.

This holding member is removed after bonding and is made of a heat-resistant material that does not deform or react with the glass at such temperatures.

Next, after removing the holding member 7, the electroluminescent element 5 is inserted, and the inserted peripheral edge 8 of the element is sealed with ultra-low melting point glass, thereby manufacturing the element of the present invention.

This ultra-low melting point glass is preferably one that can be sealed at a temperature of about 150°C (t1), which does not cause deterioration of the electroluminescent element.Specifically, as such ultra-low melting point glass, P2O[,5 ~60 PbO+5nF20~50 ZnO+ ZnFz []~30RO2+RF
40-10 (R is any one or two of 1'i and Zr) R20,+2 (RF,) O, 1-10 (R is any one of rare earths such as La and Y (or two or more) R201,0~5 (R is one or two of Nb and V) SnO
+5nF20-60.

[Example] Thermal expansion coefficient 86X 10-7/°C (Jj from room temperature to 3
00°C).

A plate glass having a transition temperature of 560° C. and a thickness of 1.1 mm was prepared. The composition of this sheet glass is S10□ 725 Na20 13.5 CaO8 Mg0 4 8120. ．． It was 2.

Then, the thermal expansion coefficient 84X 10-7/℃~+10×1
A 1.3 mm square rod was formed using low melting point glass having a temperature of 0-7/°C (room temperature to 300°C) and a transition temperature of 370°C. The composition of this glass was PbO69 B2L I 2 ZnO9 Al2O,6 in weight percent.

Next, this glass rod was placed on three peripheral edges of a glass plate as shown in FIG. 2, and a stainless steel holding member 7 having a thickness of 1.0 mm was placed in the center. Next, the other plate glass was placed on this second glass plate and then held in an electric furnace at 550°C for 110 minutes to bond.

Next, after removing the holding member 7, the electroluminescent element 5 was inserted therein and heated at 140°C for 2 hours in a dryer.
It was held for 0 minutes to remove internal moisture. Next, ultra-low melting point glass was melted at +40°C and injected into the element insertion site using a hot dispenser to seal it. The coefficient of thermal expansion of this glass is 96X 10-'/°C, transition (III degree 8
The temperature was 0° C., and the composition was P2O, 60 Pb0 10 Zn0 25 La20* 5 in weight percent.

The cross section of the sealing part of this device formed a meniscus as shown in FIG.

[Effects of the Invention] According to the present invention, since no spacer is used, there is no need to apply a frit to the spacer, which improves productivity, and the sealing portion forms a meniscus to disperse stress. Therefore, the thickness of the glass plate can be reduced, and the device can be made smaller and lighter.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a device according to the invention. FIG. 2 is an explanatory diagram showing a method of manufacturing the device according to the present invention. FIG. 3 is a plan view of the device according to the invention. FIG. 4 is a sectional view of a conventional device. 1...Spacer 3...Plate glass 4...Low melting point glass 5...Electroluminescent element Kinuta ψ-F2,・
・- 1st I￥1 1st? figure

Claims (3)

[Claims] (1) In a display device in which an electroluminescent element is provided in the gap between two glass plates and the peripheral edges of the glass plates are adhered, the peripheral edges of the glass plates are adhered with low melting point glass without using a spacer. An electroluminescent display device characterized by: (2) The low melting point glass has a coefficient of thermal expansion α_L,
When the coefficient of thermal expansion of the sheet glass is α_P (α_L−
The value of α_P) is -20×10^-^7/℃~+10×1
The display device according to claim 1, having characteristics in the range of 0^-^7/°C. (3) The display device according to claim 1, wherein the low melting point glass is formed into a rod-shaped precursor, and the precursor is placed on the peripheral edge of the glass plate and bonded to the glass plate by heating. .