JPH0447920Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial field of application] The present invention relates to a thin film EL (electroluminescence) panel that is suitable for creating a large display panel by arranging multiple elements vertically and horizontally, and in particular, Regarding sealing structure.

[Conventional technology]

The basic structure of a thin-film EL panel is shown in Figure 3, in which a front electrode 2 is placed on a transparent glass substrate 1.
EL layer 3 and back electrode 4 are sequentially laminated to form a thin film EL
In addition to forming the element 5, an envelope 25 made of glass, ceramics, or metal is placed on the glass substrate 1 in order to protect the thin film constituting the EL element 5 from moisture present in the external environment or from mechanical damage.
By sealing with the sealant 26, the thin film is isolated from the outside air and the reliability of the thin film EL panel is increased. In this case, the EL layer 3 is usually
It has a three-layer structure in which a light-emitting layer such as a ZnS:Mn film is sandwiched between two insulating layers in a sandwich pattern. The front electrode 2 and the back electrode 4 are composed of a group of striped pattern electrodes that are orthogonal to each other, and constitute an XY matrix electrode. Furthermore, among these constituent layers, all of the front electrode 2 and the EL layer 3 except the back electrode 4 are made of transparent thin films, and by selectively applying an AC voltage between the facing front electrode 2 and the back electrode 4, The EL light emitted from the EL layer 3 at the intersection is extracted from the glass substrate 1 side.

[Problem that the invention attempts to solve]

However, since the thin film EL panel having the sealing structure shown in FIG. 3 has an envelope 25 sealed on the glass substrate 1, a space is required on the substrate for sealing. Therefore, for example, when trying to construct a graphic EL display with a large display capacity by connecting separate thin-film EL panels, it is difficult to connect the thin-film EL panels at the same pitch as the light-emitting pixel pitch of each substrate. Therefore, there was a problem that the dead space due to the sealing portion became large and the display quality deteriorated.

Therefore, as shown in FIG.
There is also a sealing structure in which the light-emitting picture elements constituting the glass substrate 1 are formed up to the edges, and the entire surface on which the thin film is formed is molded with a resin 27 or a thin film having good insulation and moisture resistance such as epoxy. be. However, in an EL panel with such a structure, each light-emitting pixel is directly covered with resin 27, so the EL layer 3
When dielectric breakdown occurs due to defects in the light-emitting layer or insulating layer, self-healing does not occur, leading to a chain of dielectric breakdowns, and moisture infiltrates from the breakdown point, making moisture proofing incomplete, resulting in delamination of the thin film. There are problems such as causing

The present invention was developed to solve the above-mentioned problems, and by compactly sealing thin-film EL elements without compromising their reliability, it is possible to encapsulate multiple elements vertically and horizontally. The purpose of the present invention is to provide a thin film EL panel suitable for creating a large side-by-side display panel.

[Means for solving problems]

The thin film EL panel according to the present invention consists of sequentially laminating a front electrode, an EL layer, and a back electrode on a transparent insulating substrate, making the front electrode and back electrode orthogonal to each other to form an X-Y matrix electrode, and forming an X-Y matrix electrode. A thin-film EL element is provided with an electrode terminal extension part for each of the front electrode and the back electrode at a non-intersecting part of the front electrode and the back electrode, and a hole is provided at the intersection part of the front electrode and the back electrode and the part corresponding to the electrode terminal extension part. A plate-shaped spacer bonded with resin to the non-intersecting portion of the back electrode portion, a back plate having a hole in a portion corresponding to the electrode terminal draw-out portion and bonded with resin to the plate-shaped spacer, and the electrode terminal draw-out portion. A lead terminal electrically connected to the part and led out through each hole in the plate-shaped spacer and the back plate, and the thin film
It consists of an EL element, a plate-shaped spacer, and a reinforcing thin plate that is resin-bonded to each side of the back plate.

[Effect]

In the present invention, a plate-shaped spacer with holes corresponding to the light-emitting picture element part and the electrode lead-out terminal part is attached to the back electrode surface of the thin-film EL element.
Furthermore, by creating a structure in which the thin-film EL element is sealed by pasting together a back plate with holes provided only in the electrode lead-out terminal portion, there is no need for space on the substrate for sealing, and the thin-film EL element can be sealed. Stopping can be done compactly.

Since the plate spacer does not touch the intersection of the front and back electrodes that form the light-emitting pixel part of a thin-film EL element, even if there is a defect, that part will self-heal, and there will be no damage to other light-emitting pixel parts. No impact.

〔Example〕

Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings.

1A to 1C are cross-sectional views of the manufacturing process of a thin-film EL panel according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view of the thin-film EL element. In FIG. 2, a thin film EL element 5 is formed by sequentially laminating a front electrode 2, an EL layer 3, and a back electrode 4 on a transparent glass substrate 1, and the front electrode 2 and back electrode 4 are orthogonal to each other. The structure of the X-Y matrix electrode is similar to the conventional one described above, but each of the front electrodes 2 is drawn out from a portion of the EL layer 3 that is above the front electrode 2 and excludes the light-emitting pixel portion. In other words, there is a
Through-hole portions 6 are provided through the EL layer 3, and electrodes 7 for leading out the front electrode are formed in the through-hole portions 6. The front electrode 7 and the back electrode 4 each have a solderable electrode lead terminal portion provided on the same surface as the back electrode 4 and at a non-intersection between the front electrode and the back electrode. 8 (in the figure, only the terminal portion for drawing out the front electrode is shown), the electrodes are drawn out to the outside in a direction perpendicular to the glass substrate 1.

In addition, in the thin film EL element 5, the light emitting picture element is formed up to the edge part on the glass substrate 1,
When configuring an EL display with a large display capacity by joining, each board is designed to be joined at the same pitch as the light-emitting picture element pitch (also called electrode pitch) of the boards.

Next, the thin film EL element 5 formed in this way
As shown in Figure 1a, the EL element 5 is shown on the top.
A plate-shaped spacer 10 having lattice-shaped holes 11 and holes 12 is attached to each light-emitting pixel part (the part where the front electrode 2 and the back electrode 4 intersect) and the part corresponding to the electrode lead-out terminal part 8, respectively. . At this time, the material used for the plate-shaped spacer 10 should preferably have good insulation, heat resistance, and workability, less moisture permeation, and a low reflectance color such as black. In this embodiment, as the plate-shaped spacer 10, Corning's "Photoform Opal" processed by photolithography was used. moreover,
As shown in FIG. 1b, holes 15 are provided on the upper surface of the plate-shaped spacer 10 only in the portions corresponding to the electrode lead-out terminal portions 8 of the thin-film EL element 5, and the plate-shaped spacer 10 has the same specifications as the plate-shaped spacer 10. A sealing envelope is constructed by overlapping the plate-shaped spacer 10 and the back plate 14 by pasting together the back plate 14 made of the following material.The assembly process is shown in FIG. Explain in detail.

In FIG. 1, when attaching the thin film EL element 5 and the plate-shaped spacer 10, first, a photocurable resin 13 is applied to the bottom surface of the plate-shaped spacer 10 by dip coating, dipping, brush coating, or the like. Each light emitting pixel portion of the thin film EL element 5, each hole 11, 1 of the electrode lead terminal portion 8 and the plate spacer 10.
2, the photocurable resin 13 coated on the plate-shaped spacer 10 is exposed to exposure light 31 from the glass substrate 1 side (see a in the same figure).
The four surfaces of the back electrode on the thin film EL element 5 and the plate-shaped spacer 10 are bonded together (see b in the same figure). At this time, the photocurable resin 13 protruding onto the light emitting pixels of the thin film EL element 5 is not cured because its back electrode 4 serves as a mask and is not exposed to light. Also thin film
The resin attached to areas other than the interface between the EL element 5 and the plate-shaped spacer 10 will not harden if exposed to light in the air using an anaerobic photocurable resin (for example, Photobond (manufactured by Myojo Churchill Co., Ltd.)). This makes it possible to remove uncured resin that has adhered to excess areas. Furthermore, when drawing out each lead terminal 9 of the thin film EL element 5, an electrode drawing terminal part 8 is formed in advance, and the electrode drawing terminal part 8 is connected by soldering before or after pasting the plate-shaped spacer 10 to the outside perpendicularly to the substrate 1. It can be pulled out to.
In addition, if the thickness of the plate-shaped spacer 10 is increased to a certain extent, the lattice-shaped holes 11 in the recesses formed on each light-emitting pixel of the EL element 5 when the plate-shaped spacer 10 and the thin film EL element 5 are pasted together. A moisture absorbent 16 such as silica gel or zeolite can be embedded.

Next, in order to bond the plate-shaped spacer 10 bonded onto the thin-film EL element 5 and the back plate 14, a thermosetting resin 17 is first applied to the periphery of the plate-shaped spacer 10 as shown in FIG. 1b. After coating, thin film EL
The electrode extension portions of the element 5 and the plate-shaped spacer 10 are aligned with the holes 15 as openings in the back plate 14, and the bonding is completed by curing in a heating furnace. Finally, in order to maintain the mechanical strength of the front and back electrode lead terminals 9 vertically erected on the thin film EL element 5, the back plate 14 is coated with thermosetting resin 18 as shown in FIG. 1c.
By molding the opening, that is, the hole 15 for drawing out the terminal, it is possible to manufacture an EL panel in which the thin film EL element 5 is sealed in a moisture-proof manner.

It should be noted that the side parts of the EL panel in which the thin-film EL elements 5 are sealed are connected using resin 19 or the like to have the same dimensions as the thickness of the EL panel and also to connect the EL panels at the same pitch as the light-emitting pixel pitch. If the thin film EL element 5 and the plate-shaped spacer 10 or the plate-shaped spacer 10 are bonded together with a strip-shaped reinforcing thin plate 20 made of a stainless steel (SUS) material that is thin and does not touch, the thin-film EL element 5 and the plate-shaped spacer 10 or
It is possible to prevent moisture from entering through the interface between the back plate 14 and the back plate 14, and to reinforce the mechanical strength of the EL panel. In addition, each lead terminal 9 to the outside
This can be achieved not only by soldering but also by using conductive adhesive. In the drawings, the same reference numerals indicate the same or corresponding parts, and 32 and 33 indicate the adhesion directions of the plate-shaped spacer 10 and the back plate 14, respectively.

As described above, according to the above embodiment, the front electrode 2 and the back electrode 4 constituting the X-Y matrix electrode are drawn out from the electrode lead-out terminal portions 8 provided at the non-intersecting portions of the front electrode 2 and the back electrode 4, respectively. a thin-film EL element 5; a plate-shaped spacer 10 having holes 11 and 12 in portions corresponding to each light-emitting picture element and electrode lead-out terminal portion 8 of the thin-film EL element 5;
The thin film EL element 5 is bonded to a back plate 14 in which holes 15 are provided only in the portions corresponding to the electrode lead terminal portions 8. Then, the lead terminals 9 connected to each of the electrode lead-out terminal portions 8 are led out through the respective holes of the plate-shaped spacer 10 and the back plate 14 to correspond to each light-emitting picture element of the plate-shaped spacer 10. A moisture absorbent 16 is embedded in the lattice-shaped holes 11, and an ultra-thin strip-shaped reinforcing thin plate 20 with the same thickness as the thin-film EL element 5, the plate-shaped spacer 10, and the back plate 14 is bonded to the side surface of the cross section where the thin-film EL element 5, plate-shaped spacer 10, and back plate 14 are pasted together. By enclosing the sides of the
Compared to providing a sealing surface on the substrate of the thin film EL element 5 or coating the surface of the thin film EL element 5 with a resin, etc., the reliability of the thin film EL element 5 is not reduced, and moreover, it is compact and moisture-proof. Can be sealed. In addition, since the plate spacer 10 has a structure in which lattice-like holes 11 are provided and does not touch the light-emitting pixel portions of the thin film EL element 5, each light-emitting pixel portion may be chained due to defects in the insulating layer, etc. can be prevented from being destroyed. Furthermore, the plate-shaped spacer 10
If a material with low reflectance is used for the thin film EL element5
Reflection of external light in the space other than the light emitting part, that is, the background, is suppressed, and display quality is improved. moreover,
If the photocurable resin 13 is used to bond the thin film EL element 5 and the plate-shaped spacer 10, the thin film necessary for bonding can be
The resin protruding outside the interface between the EL element 5 and the plate-shaped spacer 10 can be effectively removed, providing advantages such as ease of workability.

Therefore, when using the EL panel of the above embodiment, when configuring an EL disk display with a large display capacity by connecting individual EL panels, the EL panels should be placed at the same pitch as the light emitting pitch on each board. This makes it possible to connect them together, making it possible to create large-area, high-capacity EL displays.

[Effect of idea]

As described above, according to the thin film EL panel of the present invention,
A structure in which a thin film EL element is sealed by laminating a plate spacer and a back plate without providing a sealing surface on the substrate of the thin film EL element or covering the entire thin film formation surface with a resin or thin film. By doing so, the thin film EL element can be sealed compactly without reducing its reliability. When a large number of thin-film EL panels are connected and arranged, the light-emitting picture elements become approximately evenly pitched at the joints, which prevents the successive destruction of each light-emitting picture element due to defects in the insulating layer, etc. There are effects such as

[Brief explanation of the drawing]

Figures 1 a to c are cross-sectional views of the manufacturing process of a thin film EL panel according to an embodiment of the present invention, Figure 2 is a partially detailed cross-sectional view of the thin film EL element shown in Figure 1, and Figures 3 and 4 are respectively 1 is a schematic cross-sectional view showing a sealing structure of a conventional thin film EL panel. 1...Glass substrate, 2...Front electrode, 3...
EL layer, 4... Back electrode, 5... Thin film EL element, 6
. . . Through-hole portion, 7 . . . Front electrode extraction electrode, 8 . . . Electrode extraction terminal portion, 9 . ...photocurable resin, 14
... Back plate, 15... Holes in back plate, 16... Moisture absorbent, 17, 18, 19... Resin, 20... Band-shaped reinforcing thin plate.

Claims (1)

[Claims for Utility Model Registration] A front electrode, an EL layer, and a back electrode are sequentially laminated on a transparent insulating substrate, and the front electrode and the back electrode are orthogonal to each other to constitute an X-Y matrix electrode. and a thin film EL element in which electrode terminal extension portions of the front electrode and the back electrode are provided at non-intersecting portions of the back electrode, and corresponding to the intersection portions of the front electrode and the back electrode and the electrode terminal extraction portions, respectively. a plate-shaped spacer whose portion is a hole and which is resin-bonded to the non-intersecting portion of the back electrode portion; and a back plate whose portion corresponding to the electrode terminal extraction portion is a hole and which is resin-bonded to the plate-shaped spacer. and lead terminals electrically connected to the electrode terminal lead-out portions and led out through holes in each of the plate-shaped spacer and the back plate; and lead terminals of the thin-film EL element, the plate-shaped spacer, and the back plate, respectively. A thin film EL panel characterized by being constructed from reinforcing thin plates with resin bonded to the sides.