JPH0584092U - EL element - Google Patents

Abstract

(57) [Abstract] [Purpose] Intrusion of water due to bending of lead electrodes,
An EL that has excellent reliability and productivity by preventing energization failure, sparks, etc. and reducing the thickness of the sealing resin.
Provide the element. A structure in which a transparent electrode having a collector, a light emitting layer, a reflective insulating layer, and a back electrode are laminated in this order on at least a glass substrate, and lead electrodes are taken out from the collector and the back electrode, respectively. In the EL element having the above, the lead electrode is formed of the same material as the current collector formed on the transparent electrode and the back electrode, and is formed on the glass substrate integrally with these electrodes. ing.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an EL element, and more particularly to an EL element having a lead electrode having a structure excellent in productivity and reliability.

[0002]

[Prior Art]

 2. Description of the Related Art In recent years, as a backlight of a display device, an EL element having uniform brightness, light weight, and thinness is used. For example, an EL element using a glass substrate on the light emitting surface side is a light emitting element in which a transparent electrode, a light emitting layer, a reflective insulating layer, and a back electrode are laminated on a transparent substrate such as glass, and the back electrode side is moisture-proof. It has a structure in which flexible back plates are laminated and the peripheral edges of the glass substrate and the back plate are hermetically sealed with an adhesive.

[0003]

[Problems to be solved by the device]

 In the EL element, the lead electrode is attached from the current collecting band on the back electrode and the transparent electrode. A thin metal plate such as a thin copper plate is used as an electrode terminal for the lead electrode, and since this lead electrode is usually provided so as to project from the EL element body, the metal plate may be corroded or bent. There is a problem that the light emitting layer is deteriorated due to breakage or moisture penetrating along the periphery of the metal plate.

In addition, when attaching the lead electrode to the back electrode, a conductive adhesive is usually used. However, since the adhesive strength of the adhesive is weak, the lead electrode may be subjected to a slight external force during the manufacturing process. There is a problem in that the product may peel off from the product, or electrical contact may be insufficient, so that troubles such as improper energization of products and sparks are likely to occur.

As a means for solving this problem, for example, Japanese Utility Model Laid-Open No. 1-81898 discloses a technique of directly solder-bonding a covered electric wire as a lead electrode to a current collecting band and a back electrode. However, in this technology, since the coated electric wire is used, not only the thickness of the entire element is increased, but also the thickness of the sealing resin is increased. It has the drawback of becoming

Therefore, the present invention has been made in view of such circumstances, and an object of the present invention is to prevent intrusion of water, defective conduction, spark, etc. due to bending of the lead electrode and the like. (EN) An EL element having excellent reliability and excellent productivity by reducing the thickness of a sealing resin.

[0007]

[Means for Solving the Problems]

 In the EL device of the present invention, at least a transparent electrode having a current collecting band on a glass substrate, a light emitting layer, a reflective insulating layer, and a back electrode are laminated in this order, and lead electrodes are respectively taken out from the current collecting band and the back electrode. In the EL element having the above-mentioned structure, the lead electrode is formed of the same material as the current collecting band formed on the transparent electrode and the back electrode, and is integrated with these electrodes to form a glass substrate. It is characterized by being formed on the top.

[0008]

【Example】

 FIG. 1 is a sectional view showing the structure of an EL device according to an embodiment of the present invention. In this EL element, a transparent electrode 2 and a current collecting band 4 are formed on a glass substrate 1 so as to be in contact with a part of the transparent electrode 2, and a light emitting layer is formed on the current collecting band 4 and the transparent electrode 2. 3, the reflective insulating layer 5, and the back electrode 6 are sequentially stacked, and the back plate 8 is further stacked on the back electrode 6, and the glass substrate 1 and the back plate 8 are hermetically sealed with the sealing resin 7. Has become. The lead electrode 9 is formed on the glass substrate with the same material as that of the current collecting band 4 and the back electrode 6, respectively. The lead electrode 9 and the current collecting band 4 and the back substrate 6 are integrally electrically connected to the outside. It has been derived.

FIG. 2 is a plan view of an EL device of another embodiment of the present invention when viewed from the back plate 8 side. It can be seen that the lead electrode 9 is formed on the transparent substrate 1 and is electrically connected together with the collector band 4 and the back electrode 6.

As the glass substrate 1, normal soda glass can be used, and the plate thickness is about 0.1 to 5.0 mm, and considering strength and weight, it is about 0.4 to 1.1 mm. Is preferred. Further, in order to prevent alkali elution from glass, a film of silica, alumina or the like may be coated.

The transparent electrode 2 can be formed of a material such as ITO, SnO ₂ , In ₂ O ₃ by a method such as vacuum deposition, sputtering, sol-gel method, etc., and is usually several Ω / □ to several thousand Ω / □. The material of 30 to 300 Ω / □ is preferably used.

The current collecting band 4 is usually formed on the transparent electrode at the edge portion (single edge portion) or the peripheral edge portion of the light emitting layer 3 with a material such as Ag paste or aluminum vapor deposition film.

The light emitting layer 3 can be formed by applying a paste in which zinc sulfide-based phosphor particles are dispersed in an appropriate organic binder to a film thickness of 20 to 60 μm using a technique such as screen printing. Similarly, the reflective insulating layer 5 can also be formed by a screen printing method with a thickness of 10 to 30 .mu.m using a paste in which a powder having a high dielectric constant such as barium titanate is dispersed in an organic binder.

The back electrode 6 can be formed of a conductive paste such as Ag paste or carbon paste by the same screen printing method, or may be formed by vacuum vapor deposition of Al, Au, or the like.

The back plate 7 may be made of any material as long as it does not allow water to permeate therethrough. For example, a metal foil, a glass plate, a material obtained by laminating a metal foil with a resin, or the like can be used.

The sealing resin is a material capable of adhering the back plate and the glass substrate. For example, thermosetting resin such as unsaturated polyester, phenol resin, epoxy resin, or adhesive such as polyolefin hot melt adhesive is used. It is possible.

The lead electrode 9 can be formed together when the current collecting band 4 and the back electrode 6 are formed. Further, in order to enhance the corrosion resistance of the lead electrode exposed on the external glass substrate, a carbon paste is formed thereon. May be formed by coating, or when a hot-melt type conductive paste is used, the metal foil may be bonded by soldering, thermocompression bonding or the like.

[0018]

[Effect of the device]

 According to the EL device of the present invention, the lead electrode is made of the same material as the current collecting band and the back electrode formed on the transparent electrode, and the lead electrode is integrated with each electrode and led out onto the glass substrate. Since there is no connection between the lead electrode, the back electrode and the current collector, there are no problems with current flow or sparks. Since the lead electrodes do not protrude from the glass substrate, there is no concern about breaking or bending due to external force. Since the lead electrode is made of the same material as the current collector and the back electrode, they can be formed at the same time, the manufacturing process can be streamlined, and the productivity is excellent. Since the lead electrode can be formed extremely thin, and at the same time, the thickness of the sealing resin can be made thin, the reliability of the EL lamp with respect to moisture can be improved and the utility value thereof is great.

[Brief description of drawings]

FIG. 1 is a sectional view showing the structure of an EL device according to an embodiment of the present invention.

FIG. 2 is a plan view of an EL device according to another embodiment of the present invention.

[Explanation of symbols]

1 ... Glass substrate 2 ... Transparent electrode 3 ... Light emitting layer 4 ... Current collecting band 5 ... Reflective insulating layer 6 ... Back electrode 7 ... Encapsulation Stop resin 8 ··· Rear plate

Claims (1)

[Scope of utility model registration request] 1. A transparent electrode having a current collecting band on at least a glass substrate, a light emitting layer, a reflective insulating layer, and a back electrode are laminated in this order, and lead electrodes are taken out from the current collecting band and the back electrode, respectively. In an EL element having a structure, the lead electrode is formed of the same material as the current collecting band and the back electrode, respectively, and is formed on a glass substrate integrally with these electrodes.
element.