JPH076876A - Thin film electroluminescent device and manufacturing method thereof - Google Patents

Abstract

(57) [Abstract] [Purpose] After a light emitting layer, an insulating layer and a first electrode composed of a conductive paste are formed by printing on a base member serving as a support,
A base in which at least the light emitting layer is sandwiched between the first electrode and the second electrode by a manufacturing method in which the base member is peeled off and a second electrode made of a conductive paste is formed by printing on the light emitting layer. A thin film (paper-like) EL element without a spacer member is obtained. [Structure] The first method for manufacturing a thin film (paper-like) EL element
Steps a to fifth steps e are included. In the first step a, a light emitting layer is formed on a base member serving as a support. In the second step b, an insulator layer is formed on the light emitting layer. In the third step c, a back electrode (first electrode) made of a conductive paste is formed on the insulating layer. In the fourth step d, the base member serving as a support is peeled from the laminated body formed in the third step c. In the fifth step e, a transparent electrode (second
Electrodes).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to an electroluminescent device (hereinafter referred to as
The present invention relates to an EL element) and a method for manufacturing the same, and particularly to a method for manufacturing a thin film (paper-like) EL element.

[0002]

2. Description of the Related Art A conventional EL device is disclosed in Japanese Patent Laid-Open No. 62-
Japanese Patent Laid-Open No. 52884 and Japanese Patent Laid-Open No. 63-10496 disclose the former (conventional example 1), which is a back electrode (base member) made of a conductive metal substance having light reflectivity such as aluminum foil. An insulating layer and a light emitting layer are sequentially formed on the upper layer,
A transparent electrode is formed by laminating a transparent conductive material such as indium oxide on a transparent resin film such as a nylon film on the light emitting layer to obtain a sandwich type EL device. The latter (conventional example 2) Is a back electrode (base member) made of a conductive metal material having a light-reflecting property, such as an aluminum foil, on which an insulating layer and a light emitting layer are sequentially formed by printing (after printing in each step, followed by drying). A transparent electrode made of a conductive paste is formed by printing on the top to obtain a coating type EL element.

[0003]

The thickness of the EL element is 200 to 240 μm in the conventional example 1 and 140 to 240 in the conventional example 2.
When the thickness is about 180 μm and sealing is performed with a moisture-proof film or the like, a gap is created due to a step due to the thickness, and good sealing cannot be obtained, which may affect the reliability of the EL element. there were. Further, in Conventional Examples 1 and 2, the back electrode is made of a support of a conductive metal substance having a light-reflecting property such as aluminum foil as described above. Therefore, the light emitting surface side is broken or cracked, and there is a problem that it cannot be applied to a flexible shape. Furthermore, when processing into an arbitrary shape in the manufacturing process, a means such as pressing is used, but as mentioned above, when considering mass production because the material is hard, an expensive metal mold made of carbide is required There was a problem that the cost would increase.

[0004]

The present invention has been made in view of the above-mentioned problems, and a light-emitting layer that emits light when an electric field is applied is sandwiched between a first electrode and a second electrode made of a conductive paste. It is characterized by

In order to realize such a thin film EL device, a first step of forming a light emitting layer on a base member serving as a support, and a second step of forming an insulating layer on the light emitting layer,
A third step of forming a laminated body by forming a first electrode made of a conductive paste on the insulator layer; a fourth step of peeling the base member from the laminated body; A fifth step of forming a second electrode made of a conductive paste on the peeling side,
It is characterized by including.

[Action]

After a light emitting layer, an insulating layer and a first electrode (for example, a back electrode) are formed by printing on a base member serving as a support, the base member is peeled off and a second electrode is formed on the light emitting layer. A thin film (paper-like) EL element without a base member can be obtained by a manufacturing method in which a transparent electrode is formed by printing.

【Example】

The present invention will be described below based on the embodiments shown in the accompanying drawings.

FIG. 1 is a sectional view of an essential part of the embodiment, in which 1 is a silver paste (manufactured by Toyobo Co., Ltd., trade name "DW" as a conductive material.
-250H-3 ") having a film thickness of 5 to 10 μm and printed on the back electrode (first electrode), 2 is an organic binder made of polyvinyl alcohol (PVA) as an organic binder material (Kuraray, trade name "PVA203") is mixed with barium titanate powder (Nippon Kasei Co., Ltd., trade name "Palcelam BT-3") as a high dielectric constant dielectric material, and an insulating layer is formed by printing with a film thickness of 5 to 10 μm, 3 is a mixture of PVA and a phosphor (manufactured by Sylvania, trade name “Phosphor 723”) in which a luminescent center of manganese is added to a base material of zinc sulfide, and the film thickness is 20 to 50 μm.
The light emitting layer 4 formed by printing with m is mixed with indium tin oxide (ITO) as a visible light transmitting conductive material in a conductive paste (manufactured by Catalysts & Chemicals, trade name "ELCOM-1207"). And a transparent electrode (second electrode) formed by printing with a film thickness of 2 to 8 μm to form a laminated body 5 by laminating the back electrode 1, the insulating layer 2 and the light emitting layer 3. The EL element 6 is composed of 5 and the transparent electrode 4.

With this structure, by applying an AC voltage between the back electrode 1 and the transparent electrode 4, the EL element 6 in which the light emitting layer 3 emits light is formed.

Next, the manufacturing method of the EL element 6 will be described with reference to the sectional view of the essential part of the EL element 6 shown in FIG. 3 corresponding to FIG. 2 using the process flow chart of the manufacturing method shown in FIG. To do.

In the light emitting layer printing step (first step) a,
A light emitting layer 3 is formed by printing on a base member 7 which is a sheet-like support and is made of a material such as PET or polyethylene (a in FIG. 3).
After drying in a high temperature furnace for about 30 minutes, the insulator layer printing process (second
Step b) and back electrode printing step (third step) c, the insulator layer 2 and the back electrode 1 are sequentially formed by printing on the light emitting layer 3 (b and c in FIG. 3), and in each step, the light emitting layer is formed. Similar to the printing step a, it is dried in a high temperature furnace to form the laminated body 5 on the base member 7. Next, in the base member peeling step (fourth step) d, the base member 7 is peeled from the laminate 5 (d in FIG. 3), and in the transparent electrode printing step (fifth step) e, light is emitted. Layer 3
The transparent electrode 4 is formed by printing on the peeling side of the base member 7 of E.
The L element 6 is formed (e in FIG. 3), and this EL element 6 is dried in a high temperature furnace for about 2 hours.

By this manufacturing method, the thin-film (paper-like) EL element 6 without the base member 7 can be obtained.

Although the thin-film (paper-like) EL element 6 without the base member 7 was obtained by the above-mentioned manufacturing method (a to e in FIG. 2), the order of steps can be appropriately changed and the thin-film (paper-like) can be used. EL)
The order of steps is not limited to this as long as it is a method for obtaining an element. For example, the back electrode printing step (third step) c and the transparent electrode printing step (fifth step) e are interchanged to make the first electrode transparent. The electrode 4 and the second electrode may be the back electrode 1. Alternatively, it is possible to add a step of providing another insulating layer so as to face the insulating layer 2 with the light emitting layer 3 interposed therebetween.

Although not shown, like the conventional EL element, a current collector made of silver paste or the like is formed on the transparent electrode 4 and a lead pin for applying an external AC voltage is provided in the circumferential direction. It is fixed to the current collector and the back electrode 1 by an adhesive means such as a conductive tape so as to be pulled out, and if necessary, the EL element 6 is surrounded by a moisture-proof film so as to be isolated from the ambient atmosphere and laminated. The EL element 6 which is much thinner than the conventional one can be obtained even with such a structure.

If a paste-like moisture-proof layer is formed by printing on the back electrode 1 and the transparent electrode 4 instead of the moisture-proof film, an even thinner thin film (paper-like) EL element 6 can be obtained. .

Further, by replacing the back electrode 1 and the current collector with a nickel paste, it is possible to prevent the migration phenomenon from occurring at the time of the silver paste and to prevent the thin film (paper-like) EL.
The life as an element can be extended.

[0017]

According to the first aspect of the present invention, at least a light emitting layer that emits light when an electric field is applied is formed of a conductive paste.
A thin film EL device characterized by being sandwiched between an electrode and a second electrode, and as a method of manufacturing such a thin film EL device, a first step of forming a light emitting layer on a base member serving as a support. A second step of forming an insulator layer on the light emitting layer,
A third step of forming a laminated body by forming a first electrode made of a conductive paste on the insulator layer; a fourth step of peeling the base member from the laminated body; A fifth step of forming a second electrode made of a conductive paste on the peeling side,
The thickness of the EL element can be made extremely thin (about 100 μm thinner than the conventional one), which is, for example, about 67 to 84% reduction as compared with the conventional example 1. The reduction is about 56 to 77% with respect to the conventional example 2, and the thickness can be reduced to half or less with respect to any of the conventional examples.

Therefore, when sealing with a moisture-proof film, good sealing can be achieved, the reliability as an EL element is improved, and even when it is bent and used, there is no base member such as an aluminum foil, so it has a flexible shape. Can handle.

Further, in the manufacturing process, since the EL element is very thin (paper-like), conventionally, by means such as pressing, E
Although the L element has an arbitrary shape, the EL element can be processed into a free shape without using a mold (cutting can be performed with a cutter or the like), so that the facility cost is low and the production cost can be kept low. Has a great effect on the production of.

[Brief description of drawings]

FIG. 1 is a sectional view of an essential part of an embodiment of the present invention.

FIG. 2 is a process flow chart of the manufacturing method according to the embodiment.

FIG. 3 is a cross-sectional view of an essential part of an EL element corresponding to the above process.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Back electrode (1st electrode) 2 Insulator layer 3 Light emitting layer 4 Transparent electrode (2nd electrode) 5 Laminated part 6 EL element 7 Base member a Light emitting layer printing step (1st step) b Insulating layer printing step (Second step) c Back electrode printing step (third step) d Base member peeling step (fourth step) e Transparent electrode printing step (fifth step)

Claims (2)

[Claims] 1. A light emitting layer that emits light at least by applying an electric field, a first electrode and a second electrode made of a conductive paste.
A thin film electroluminescent device characterized by being sandwiched between electrodes. 2. A first step of forming a light emitting layer on a base member serving as a support, a second step of forming an insulator layer on the light emitting layer, and a conductive sheet on the insulator layer. A third step for forming a laminated body by forming a first electrode made of a strike, a fourth step for peeling the base member from the laminated body, and a conductive paste on the peeling side of the light emitting layer. And a fifth step of forming a second electrode.