WO2013042533A1 - Organic electroluminescent panel and method for producing organic electroluminescent panel - Google Patents

Abstract

An organic EL panel, which is such that an organic EL element resulting from forming at least a positive electrode, a light-emitting layer, and a negative electrode in the given order on a support substrate is sealed by a conductive sealing member with an insulating adhesion layer provided on the negative electrode therebetween, wherein a plurality of the conductive sealing members are provided, and the positive electrode and negative electrode are each electrically connected to different conductive sealing members among the plurality of conductive sealing members.

Description

Organic electroluminescence panel and method for manufacturing organic electroluminescence panel

The present invention relates to an organic electroluminescence panel and a method for producing an organic electroluminescence panel.

Conventionally, an organic electroluminescence element (hereinafter also referred to as an organic EL element) is known as a planar light emitting element which is a planar light source body. The organic EL element has a configuration including an organic functional layer sandwiched between a pair of electrodes on a support substrate, and the organic functional layer includes a plurality of layers having different functions, for example, a hole injection layer, A hole transport layer, a light emitting layer, an electron transport layer, an electron injection layer, and the like are provided.
Since such an organic EL element emits light when a DC voltage is supplied, a connection part (feeding part) for applying a DC voltage from the outside to the electrode part of the organic EL element is required.
Various systems are disclosed as the structure of such a power feeding unit. For example, in the organic EL element 20 shown in FIG. 4, the organic functional layer 23 is sandwiched between the pair of electrodes 22 and 24 on the support substrate 21, and the organic functional layer 23 is covered in such an organic EL element 20. A sealing member 27 is provided via an adhesive layer 25 so that side end portions of the anode 22 and the cathode 24 are exposed. And the technique by which the anode power supply part 28 and the cathode power supply part 29 are arrange | positioned on the anode 22 and the cathode 24 exposed from the side edge part of the sealing member 27 is disclosed.
Further, for example, a technique is known in which an anode power supply unit and a cathode power supply unit are arranged on the transparent substrate along two parallel sides of a rectangular light emitting unit formed on the transparent substrate. (See Patent Document 1).

JP 2010-198980 A

However, as described in FIG. 4 and Patent Document 1 described above, since there is no organic functional layer that is a light emitting unit above the anode power supply unit and the cathode power supply unit, light is emitted from the power supply unit. I can't take it out. For this reason, when the area of the power feeding portion is large, the ratio of the portion from which the emitted light can be extracted with respect to the substrate area of the organic EL element becomes a problem. That is, as in Patent Document 1, when a power feeding unit is provided on the transparent substrate along both ends of the two sides of the light emitting unit, it is necessary to secure an area necessary for connecting a power feeding wiring (FPC or the like). Therefore, a region where the emitted light cannot be extracted (non-light emitting area E (see FIG. 4)) becomes large.
Moreover, when such an organic EL element is applied to a large luminaire or the like, and a plurality of organic EL elements are arranged on a plane to emit light, a non-light emitting area between the organic EL elements as a whole becomes conspicuous, and the organic EL elements arranged in this way When a group is applied to a luminaire, there is a problem that the size of the luminaire becomes large in order to obtain appropriate illumination brightness.
This invention is made | formed in view of the said situation, and it aims at providing the manufacturing method of the organic electroluminescent panel which can make the non-light-emitting area in planar view small, and an organic electroluminescent panel.

According to one aspect of the present invention, an organic electroluminescence element in which at least a first electrode, a light emitting layer, and a second electrode are formed in this order on a supporting substrate is provided on the second electrode. An organic electroluminescence panel sealed with a conductive sealing member through a conductive adhesive layer,
A plurality of the conductive sealing members are provided,
The organic electroluminescence panel, wherein the first electrode and the second electrode are electrically connected to different conductive sealing members among the plurality of conductive sealing members. Provided.
According to another aspect of the present invention, an organic electroluminescent element in which at least a first electrode, a light emitting layer, and a second electrode are formed in this order on a support substrate is provided on the second electrode. An organic electroluminescence panel manufacturing method for manufacturing an organic electroluminescence panel sealed with a conductive sealing member via an insulating adhesive layer,
A plurality of the conductive sealing members are provided,
The method for producing an organic electroluminescence panel, wherein the first electrode and the second electrode are electrically connected to different conductive sealing members among the plurality of conductive sealing members. Is provided.

According to the present invention, the non-light emitting area in plan view can be reduced.

The top view of an organic electroluminescent panel for showing 1st Embodiment. The top view of an organic EL element for showing 1st Embodiment. FIG. 1B is a cross-sectional view taken along the line II of FIG. 1A. It is for demonstrating the modification of the organic electroluminescent panel of FIG. 1C, and is sectional drawing of an organic electroluminescent panel. Sectional drawing of an organic electroluminescent panel for showing 2nd Embodiment. Sectional drawing of an organic EL element for showing a prior art example.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The embodiments of the present invention are not limited to these.
[First Embodiment]
<< Organic EL panel >>
1A is a plan view of the organic EL panel of the present invention, FIG. 1B is a plan view of the organic EL element, and FIG. 1C is a cross-sectional view taken along the line II of FIG. 1A.
As shown in FIGS. 1A and 1C, the organic EL panel 100 includes a first electrode (anode 2), an organic functional layer 3 including a light emitting layer, and a second electrode (cathode 4) on a support substrate 1. Insulating adhesive layers 5 and 6 (hereinafter simply referred to as adhesive layers) and a plurality of conductive sealing members 7 to 9 (hereinafter simply referred to as sealing members) laminated on the second electrode 4 in this order. , Is provided. In the present embodiment, the first electrode is described as the anode 2 and the second electrode is described as the cathode 4.

The anode 2 is provided on the upper surface of the support substrate 1 so as to cover the support substrate 1 except for one side end portion (hereinafter referred to as a right end portion) of the support substrate 1. It extends to the side end (hereinafter referred to as the left end).
The organic functional layer 3 is provided so as to cover the anode 2 except for the left end portion of the anode 2 from a part of the exposed upper surface of the support substrate 1 that is not covered with the anode 2.
The cathode 4 is provided so as to cover the organic functional layer 3 except for the left end portion of the organic functional layer 3 from the exposed upper surface of the support substrate 1 that is not covered with the anode 2 and the organic functional layer 3. , Extending to the right end of the support substrate 1.
The support substrate 1, the anode 2, the organic functional layer 3 and the cathode 4 are sealed by the first and second insulating adhesive layers 5 and 6 and a plurality of sealing members 7 to 9. It has a stop structure.
In the present invention, the state in which the cathode 4 is sealed (covered) by the plurality of sealing members 7 to 9 is called an organic EL panel 100, and the state in which the support substrate 1 to the cathode 4 are formed is organic. This is referred to as EL element 10.

Among the plurality of sealing members 7 to 9, the first sealing member 7 and the second sealing member 8 are disposed on the organic EL element 10 via the first adhesive layer 5. That is, the first adhesive layer 5 is formed on the exposed upper surface of the anode 2, the organic functional layer 3, and the cathode 4. And the 1st sealing member 7 and the 2nd sealing member 8 are provided in the said 1st contact bonding layer 5 at predetermined intervals on the same plane.
Further, in the gap S formed between the right end portion of the first sealing member 7 and the left end portion of the second sealing member 8, the first sealing member 7 and the second sealing member 8. A second adhesive layer 6 is formed at the center of the upper surface of the substrate. A third sealing member 9 is provided on the second adhesive layer 6. Thus, the third sealing member 9 covers the gap S between the first and second sealing members 7 and 8.
Thus, in the organic EL panel 100, the first to third sealing members 7 to 9 are arranged so as not to be in electrical contact with each other via the first and second adhesive layers 5 and 6. The organic EL panel 100 has a sealing structure in which the organic EL element 10 is sealed by the first to third sealing members 7 to 9.

The first and second sealing members 7 and 8 have substantially the same size. The third sealing member 9 is slightly smaller than the first and second sealing members 7 and 8 in FIGS. 1A to 1C, but is the same as the first and second sealing members 7 and 8. It may be a size or may be larger than the first and second sealing members 7 and 8. When the size of the third sealing member 9 is increased, the distance from the left and right end portions of the third sealing member 9 to the gap S between the first and second sealing members 7 and 8 becomes longer. Therefore, it is possible to more reliably block moisture and oxygen from entering, and to improve the sealing function.
Further, when the support substrate 1 and the entire first to third sealing members 7 to 9 are viewed in plan, the outer shape of the support substrate 1 and the entire first to third sealing members 7 to 9 are displayed. And may be adjusted as appropriate so as to be the same size.

The first to third sealing members 7 to 9 have conductivity. For example, a metal plate and metal foil are mentioned, and metal foil is preferable. Examples of the metal foil include copper foil, aluminum foil, gold foil, brass foil, nickel foil, titanium foil, copper alloy foil, stainless steel foil, tin foil, and high nickel alloy foil. Among these various metal foils, a particularly preferable metal foil is an aluminum foil.
As a method for producing the metal foil, rolling or the like is mainly mentioned. The metal foil refers to a metal foil formed by the rolling, but a metal thin film or a conductive film formed by sputtering or vapor deposition on a polymer film. It may be a conductive film formed from a fluid electrode material such as a paste.
As the material for the polymer film, various materials described in New Development of Resin Packaging Materials (Toray Research Center, Inc.) can be used. For example, polyethylene resin, polypropylene resin, polyethylene terephthalate resin, Examples include polyamide resins, ethylene-vinyl alcohol copolymer resins, ethylene-vinyl acetate copolymer resins, acrylonitrile-butadiene copolymer resins, cellophane resins, vinylon resins, vinylidene chloride resins, and the like. Resins such as polypropylene resin and nylon resin may be stretched and further coated with vinylidene chloride resin.
In addition, a polyethylene resin having a low density or a high density can be used.
As a method for laminating the polymer film on one side of the metal foil, a generally used laminating machine can be used. When laminating, an adhesive such as polyurethane, polyester, epoxy, or acrylic can be used as the adhesive. You may use a hardening | curing agent together as needed. A hot melt lamination method, an extrusion lamination method and a coextrusion lamination method can also be used, but a dry lamination method is preferred.
Further, when the metal foil is formed by sputtering or vapor deposition, or is formed from a fluid electrode material such as a conductive paste, the metal foil may be formed using a polymer film as a base material.
In addition, you may provide a protective film or a protective plate in order to raise the mechanical strength of an element on the outer side of the metal foil which made such a polymer film a base material. As the protective film and the protective plate, a glass plate, a polymer plate / film, a metal plate / film, and the like can be used. However, it is preferable to use a polymer film because it is lightweight and thin.

The adhesive that forms the first and second adhesive layers 5 and 6 is an insulating material, for example, a thermosetting adhesive made of a thermoplastic resin, an epoxy resin, an acrylic resin, a silicone resin, or the like. Resins can be used. More specifically, photo-curing and thermosetting adhesives having a reactive vinyl group of acrylic acid-based oligomers and methacrylic acid-based oligomers, and moisture-curing adhesives such as 2-cyanoacrylates can be mentioned. . Moreover, heat | fever and chemical curing types (two-component mixing), such as an epoxy type, can be mentioned. Moreover, hot-melt type polyamide, polyester, and polyolefin can be mentioned. Moreover, a cationic curing type ultraviolet curing epoxy resin adhesive can be mentioned.

In addition, since the organic EL element 10 may be deteriorated by heat treatment, it is preferable that the adhesive can be cured from room temperature to 80 ° C. A desiccant may be dispersed in the adhesive. Application | coating of the adhesive agent to a sealing part may use commercially available dispenser, and may print it like screen printing.

The gap between the first to third sealing members 7 to 9 and the organic EL element 10 has a filling structure filled with the first and second adhesive layers 5 and 6, but in the gas phase and the liquid phase, nitrogen, An inert gas such as argon or an inert liquid such as fluorinated hydrocarbon or silicon oil may be injected. A vacuum can also be used. In the case of such a hollow structure, at least the first sealing member 7 and the organic EL element 10 and the second sealing member 8 and the organic EL element 10 are each locally insulatively bonded. A layer is provided so that a predetermined interval can be maintained. Insulating adhesive layers are also locally provided between the first sealing member 7 and the third sealing member 9 and between the second sealing member 8 and the third sealing member 9. Is provided so that a predetermined interval can be maintained.
In addition, a hygroscopic compound can be sealed in the gap between the first to third sealing members 7 to 9 and the organic EL element 10.

Examples of the hygroscopic compound include metal oxides (for example, sodium oxide, potassium oxide, calcium oxide, barium oxide, magnesium oxide, aluminum oxide) and sulfates (for example, sodium sulfate, calcium sulfate, magnesium sulfate, cobalt sulfate). Etc.), metal halides (eg calcium chloride, magnesium chloride, cesium fluoride, tantalum fluoride, cerium bromide, magnesium bromide, barium iodide, magnesium iodide etc.), perchloric acids (eg perchloric acid) Barium, magnesium perchlorate, and the like), and anhydrous salts are preferably used in sulfates, metal halides, and perchloric acids.

The organic EL panel 100 includes an anode power supply unit 11 for supplying power to the anode 2 from an external power source, and a cathode power supply unit 12 for supplying power to the cathode 4 from an external power source. .
The anode power supply unit 11 is provided on the upper surface of the first sealing member 7, and the cathode power supply unit 12 is provided on the upper surface of the second sealing member 8. The power feeding unit 12 is provided on a different sealing member. The anode power supply unit 11 and the cathode power supply unit 12 are provided outside the first and second adhesive layers 5 and 6.

The left end portion of the first sealing member 7 and the left end portion of the anode 2 are electrically connected.
Examples of the electrical connection method include a method capable of connecting in a narrow area. For example, as shown in FIG. 1A to FIG. 1C, it is electrically connected by soldering 13 so as to cover the ends of both members. A method of connecting, a method of connecting and electrically connecting by forming a conductive paste so as to cover the ends of both members, and joining the ends of both members by laser welding, ultrasonic welding, or caulking And a method of electrical connection. In addition, as shown in FIG. 2, a method of electrically connecting the ends of both members by dispersing the conductive filler 14 in the first adhesive layer 5 can be mentioned. In this case, the conductive filler 14 is dispersed in the first adhesive layer 5 so as to be in contact with the lower surface of the first sealing member 7 and the upper surface of the anode 2.
According to such an electrical connection method, it is a simple method. In particular, when forming the solder 13 or the conductive paste, the outside of the first adhesive layer 5 is covered with the solder 13 or the conductive paste. Therefore, as compared with the end sealing only by the first adhesive layer 5, it is possible to reliably suppress the intrusion of moisture and oxygen and perform the end sealing.
Further, the right end portion of the second sealing member 8 and the right end portion of the cathode 4 are also electrically connected. Examples of the electrical connection method include the same connection methods as described above.

The organic functional layer 4 can be configured as long as it includes at least a light emitting layer. In addition to the light emitting layer, the organic functional layer 4 includes, for example, a hole transport layer, an electron transport layer, a cathode buffer layer (electron injection layer) described later, and the like. . And by sending an electric current through such an organic functional layer 4 (light emitting layer), the light emitting material in a light emitting layer light-emits.

<< Method for Manufacturing Organic EL Panel >>
Hereinafter, a method for manufacturing the organic EL panel 100 will be described.
First, an adhesive is applied to the exposed upper surfaces of the anode 2, the organic functional layer 3, and the cathode 4 of the organic EL element 10, and the first and second sealing are performed on the first adhesive layer 5 made of the applied adhesive. The members 7 and 8 are provided at a predetermined interval on the same plane. Thus, the first and second sealing members 7 and 8 cover the portion excluding the central portion of the organic EL element 10.
Next, an adhesive is applied to the gap S between the first and second sealing members 7 and 8 and the central portion on the first and second sealing members 7 and 8, and the first made of the applied adhesive. A third sealing member 9 is provided for the two adhesive layers 6. Thus, a sealing structure in which the gap S between the first and second sealing members 7 and 8 is covered is obtained.
Thereafter, the left end of the anode 2 and the left end of the first sealing member 7 are electrically connected by the above-described electrical connection method.
Similarly, the right end of the cathode 3 and the right end of the second sealing member 8 are electrically connected by the above-described electrical connection method.
Note that, when the conductive filler 14 is electrically connected, the conductive filler 14 is dispersed in the first adhesive layer 5 in advance, and then the first and second adhesive layers 5 are connected to the first adhesive layer 5. Sealing members 7 and 8 are provided.
Finally, the anode power supply unit 11 is formed on the first sealing member 7, and the cathode power supply unit 12 is formed on the second sealing member 8, whereby the organic EL panel 100 is obtained.

The first adhesive layer 5 is formed by coating the exposed upper surfaces of the anode 2, the organic functional layer 3, and the cathode 4, and then the first and second sealing members are applied to the first adhesive layer 5. 7 and 8 are provided, but conversely, an adhesive is applied to the first and second sealing members 7 and 8 to form the first adhesive layer 5, and this first adhesive layer 5 is used as the anode 2. The first and second sealing members 7 and 8 may be provided on the exposed upper surfaces of the organic functional layer 3 and the cathode 4.
Furthermore, these sealings may be performed in any environment as long as moisture and oxygen can be prevented from entering from the external environment of the organic EL element 10, for example, in a vacuum (low pressure) environment, nitrogen, or the like. An atmospheric pressure environment substituted with an inert gas may be used.

As described above, the first to third conductive sealing members 7 to 9 are provided, and the anode 2 and the cathode 4 are electrically connected to the first and second sealing members 7 and 8, respectively. Since they are connected, the anode power supply part 11 and the cathode power supply part 12 can be provided on the surfaces of the first and second sealing members 7 and 8 on the side opposite to the support substrate 1. As a result, since it is not necessary to provide the anode and cathode power supply portions on the support substrate 1 as in the prior art, the non-light emitting area in plan view of the organic EL element 10 can be reduced.
In addition, since the anode power supply part 11 and the cathode power supply part 12 can be provided on the surface of the first and second sealing members 7 and 8 on the opposite side of the support substrate 1, the power supply area can be increased compared to the conventional case. A large amount can be secured, and wiring connection such as FPC can be easily performed, and cost can be reduced.
Further, when the support substrate 1 and the entire first to third sealing members 7 to 9 are viewed in plan, the outer shape of the support substrate 1, the entire first to third sealing members 7 to 9, and When it is made the same size, it looks good and the overall strength of the panel increases. In addition, when the overall size of the first to third sealing members 7 to 9 is the same as the outer shape of the support substrate 1, the area for sealing the organic EL element 10 increases. In addition, moisture and oxygen intrusion into the organic EL element 10 can be reliably suppressed, and the life of the organic EL element 10 can be improved.
Further, a third sealing member 9 is laminated on the gap S between the first and second sealing members 7 and 8 adjacent to each other on the same plane with the second adhesive layer 6 interposed therebetween. Since the EL element 10 has a sealing structure in which the first to third sealing members 7 to 9 are covered, moisture and oxygen permeation can be reliably suppressed also in this respect.

<< Organic EL element >>
Hereinafter, although the preferable specific example of the layer structure of the organic EL element 10 is shown, this invention is not limited to this.
(I) Anode / light emitting layer / electron transport layer / cathode (ii) Anode / hole transport layer / light emitting layer / electron transport layer / cathode (iii) Anode / hole transport layer / light emitting layer / hole blocking layer / electron Transport layer / cathode (iv) anode / hole transport layer / light emitting layer / hole blocking layer / electron transport layer / cathode buffer layer / cathode (v) anode / anode buffer layer / hole transport layer / light emitting layer / hole Blocking layer / electron transport layer / cathode buffer layer / cathode Here, the light emitting layer preferably contains at least two kinds of light emitting materials having different emission colors, and a single layer or a light emitting layer comprising a plurality of light emitting layers A unit may be formed. The hole transport layer also includes a hole injection layer and an electron blocking layer. In the present invention, the layer excluding the anode and the cathode is referred to as an organic functional layer.

<Light emitting layer>
The light-emitting layer is a layer that emits light by recombination of electrons and holes injected from the electrode, the electron transport layer, or the hole transport layer, and the light-emitting portion is the light-emitting layer even in the light-emitting layer. It may be an interface with an adjacent layer.

The structure of the light emitting layer according to the present invention is not particularly limited as long as the light emitting material included satisfies the above requirements.

Also, there may be a plurality of layers having the same emission spectrum or emission maximum wavelength.

It is preferable to have a non-light emitting intermediate layer between each light emitting layer.

In the present invention, the total thickness of the light emitting layers is preferably in the range of 1 nm to 100 nm, and more preferably 30 nm or less because a lower driving voltage can be obtained. In addition, the sum total of the film thickness of the light emitting layer said by this invention is a film thickness also including this intermediate | middle layer, when a nonluminous intermediate | middle layer exists between light emitting layers.

The film thickness of each light emitting layer is preferably adjusted to a range of 1 nm to 50 nm, and more preferably adjusted to a range of 1 nm to 20 nm. There is no particular limitation on the relationship between the film thicknesses of the blue, green and red light emitting layers.

For the production of the light emitting layer, a light emitting material or a host compound, which will be described later, is formed by forming a film by a known thinning method such as a vacuum deposition method, a spin coating method, a casting method, an LB method, an ink jet method, or the like. it can.

In the present invention, a plurality of light emitting materials may be mixed in each light emitting layer, or a phosphorescent light emitting material and a fluorescent light emitting material may be mixed and used in the same light emitting layer.

In the present invention, the light emitting layer preferably contains a host compound and a light emitting material (also referred to as a light emitting dopant compound) and emits light from the light emitting material.

In the present invention, the host compound contained in the light emitting layer of the organic EL device is preferably a compound having a phosphorescence quantum yield of phosphorescence emission at room temperature (25 ° C.) of less than 0.1. More preferably, the phosphorescence quantum yield is less than 0.01. Moreover, it is preferable that the volume ratio in the layer is 50% or more among the compounds contained in a light emitting layer.

As the host compound, known host compounds may be used alone or in combination of two or more. By using a plurality of types of host compounds, it is possible to adjust the movement of charges, and the organic EL element can be made highly efficient. Moreover, it becomes possible to mix different light emission by using multiple types of luminescent material mentioned later, and can thereby obtain arbitrary luminescent colors.

The host compound used in the present invention may be a conventionally known low molecular compound or a high molecular compound having a repeating unit, and a low molecular compound having a polymerizable group such as a vinyl group or an epoxy group (evaporation polymerizable light emitting host). )But it is good.

As the known host compound, a compound that has a hole transporting ability and an electron transporting ability, prevents the emission of light from being increased in wavelength, and has a high Tg (glass transition temperature) is preferable. Here, the glass transition point (Tg) is a value determined by a method based on JIS-K-7121 using DSC (Differential Scanning Colorimetry).

Specific examples of known host compounds include compounds described in the following documents. For example, Japanese Patent Application Laid-Open Nos. 2001-257076, 2002-308855, 2001-313179, 2002-319491, 2001-357777, 2002-334786, 2002-8860 Gazette, 2002-334787, 2002-15871, 2002-334788, 2002-43056, 2002-334789, 2002-75645, 2002-338579 No. 2002-105445, No. 2002-343568, No. 2002-141173, No. 2002-352957, No. 2002-203683, No. 2002-363227, No. 2002-231453. No. 2003-3165, No. 2002-234888, No. 2003-27048, No. 2002-255934, No. 2002-286061, No. 2002-280183, No. 2002-299060. No. 2002-302516, No. 2002-305083, No. 2002-305084, No. 2002-308837, and the like.

Next, the light emitting material will be described.

As the light-emitting material according to the present invention, a fluorescent compound or a phosphorescent material (also referred to as a phosphorescent compound or a phosphorescent compound) is used.

In the present invention, a phosphorescent material is a compound in which light emission from an excited triplet is observed. Specifically, it is a compound that emits phosphorescence at room temperature (25 ° C.), and the phosphorescence quantum yield is 0 at 25 ° C. A preferred phosphorescence quantum yield is 0.1 or more, although it is defined as 0.01 or more compounds.

The phosphorescent quantum yield can be measured by the method described in Spectra II, page 398 (1992 version, Maruzen) of Experimental Chemistry Lecture 4 of the 4th edition. The phosphorescence quantum yield in a solution can be measured using various solvents. However, when a phosphorescent material is used in the present invention, the phosphorescence quantum yield (0.01 or more) is achieved in any solvent. Just do it.

There are two types of light emission of the phosphorescent material. In principle, the carrier recombination occurs on the host compound to which the carrier is transported to generate an excited state of the host compound, and this energy is transferred to the phosphorescent material. Energy transfer type to obtain light emission from the phosphorescent light emitting material, and another one is that the phosphorescent light emitting material becomes a carrier trap, and recombination of carriers occurs on the phosphorescent light emitting material, and light emission from the phosphorescent light emitting material is obtained. Although it is a trap type, in any case, the excited state energy of the phosphorescent material is required to be lower than the excited state energy of the host compound.

The phosphorescent light-emitting material can be appropriately selected from known materials used for the light-emitting layer of the organic EL element, and is preferably a complex compound containing a group 8-10 metal in the periodic table of elements. More preferably, an iridium compound, an osmium compound, a platinum compound (platinum complex compound), or a rare earth complex, and most preferably an iridium compound.

Specific examples of compounds used as phosphorescent materials are shown below, but the present invention is not limited thereto. These compounds are described, for example, in Inorg. Chem. 40, 1704 to 1711, and the like.

Fluorescent light emitters can also be used in the organic EL device according to the present invention. Representative examples of fluorescent emitters (fluorescent dopants) include coumarin dyes, pyran dyes, cyanine dyes, croconium dyes, squalium dyes, oxobenzanthracene dyes, fluorescein dyes, rhodamine dyes, and pyrylium dyes. Examples thereof include dyes, perylene dyes, stilbene dyes, polythiophene dyes, and rare earth complex phosphors.

Conventionally known dopants can also be used in the present invention. For example, International Publication No. 00/70655 pamphlet, JP-A Nos. 2002-280178, 2001-181616, 2002-280179, 2001 -181617, 2002-280180, 2001-247859, 2002-299060, 2001-313178, 2002-302671, 2001-345183, 2002 No. 324679, WO 02/15645, JP 2002-332291, 2002-50484, 2002-332292, 2002-83684, JP 2002-540572, JP 002-117978, 2002-338588, 2002-170684, 2002-352960, WO01 / 93642, JP2002-50483, 2002-1000047 No. 2002-173684, No. 2002-359082, No. 2002-175484, No. 2002-363552, No. 2002-184582, No. 2003-7469, No. 2002-525808 JP2003-7471, JP2002-525833A, JP2003-31366A, 2002-226495, 2002-234894, 2002-233506, 2002-2417. No. 1, No. 2001-319779, No. 2001-319780, No. 2002-62824, No. 2002-1000047, No. 2002-203679, No. 2002-343572, No. 2002-203678. Gazettes and the like.

In the present invention, at least one light emitting layer may contain two or more kinds of light emitting materials, and the concentration ratio of the light emitting materials in the light emitting layer may vary in the thickness direction of the light emitting layer.

《Middle layer》
In the present invention, a case where a non-light emitting intermediate layer (also referred to as an undoped region) is provided between the light emitting layers will be described.

In the case of having a plurality of light emitting layers, the non-light emitting intermediate layer is a layer provided between the light emitting layers.

The film thickness of the non-light emitting intermediate layer is preferably in the range of 1 nm to 20 nm, and further in the range of 3 nm to 10 nm suppresses interaction such as energy transfer between adjacent light emitting layers, and the device This is preferable because a large load is not applied to the current-voltage characteristics.

The material used for the non-light emitting intermediate layer may be the same as or different from the host compound of the light emitting layer, but may be the same as the host material of at least one of the adjacent light emitting layers. preferable.

The non-light-emitting intermediate layer may contain a non-light-emitting layer, a compound common to each light-emitting layer (for example, a host compound), and each common host material (where a common host material is used) Including the case where the physicochemical characteristics such as phosphorescence emission energy and glass transition point are the same, and the case where the molecular structure of the host compound is the same, etc.) The barrier is reduced, and the effect of easily maintaining the injection balance of holes and electrons even when the voltage (current) is changed can be obtained. Furthermore, by using a host material having the same physical characteristics or the same molecular structure as that of the host compound contained in each light emitting layer in the undoped light emitting layer, device fabrication, which is a major problem in conventional organic EL device fabrication, is achieved. Complexity can also be eliminated.

In the case of using the organic EL element in the present invention, the host material is responsible for carrier transportation, and therefore a material having carrier transportation ability is preferable. Carrier mobility is used as a physical property representing carrier transport ability, but the carrier mobility of an organic material generally depends on the electric field strength. Since a material having a high electric field strength dependency easily breaks the balance between injection and transport of holes and electrons, it is preferable to use a material having a low electric field strength dependency of mobility for the intermediate layer material and the host material.

On the other hand, in order to optimally adjust the injection balance of holes and electrons, it is also preferable that the non-light emitting intermediate layer functions as a blocking layer described later, that is, a hole blocking layer and an electron blocking layer. It is done.

<< Injection layer: electron injection layer, hole injection layer >>
The injection layer is provided as necessary, and there are an electron injection layer and a hole injection layer, and as described above, it exists between the anode and the light emitting layer or the hole transport layer and between the cathode and the light emitting layer or the electron transport layer. May be.

An injection layer is a layer provided between an electrode and an organic layer in order to reduce drive voltage and improve light emission luminance. “Organic EL element and its forefront of industrialization (issued by NTT Corporation on November 30, 1998) 2), Chapter 2, “Electrode Materials” (pages 123 to 166) in detail, and includes a hole injection layer (anode buffer layer) and an electron injection layer (cathode buffer layer).

The details of the anode buffer layer (hole injection layer) are also described in JP-A-9-45479, JP-A-9-260062, JP-A-8-288069 and the like. As a specific example, copper phthalocyanine is used. Examples thereof include a phthalocyanine buffer layer represented by an oxide, an oxide buffer layer represented by vanadium oxide, an amorphous carbon buffer layer, and a polymer buffer layer using a conductive polymer such as polyaniline (emeraldine) or polythiophene.

The details of the cathode buffer layer (electron injection layer) are described in JP-A-6-325871, JP-A-9-17574, JP-A-10-74586, and the like. Specifically, strontium, aluminum, etc. Metal buffer layer typified by lithium, alkali metal compound buffer layer typified by lithium fluoride, alkaline earth metal compound buffer layer typified by magnesium fluoride, oxide buffer layer typified by aluminum oxide, etc. . The buffer layer (injection layer) is preferably a very thin film, and the film thickness is preferably in the range of 0.1 nm to 5 μm, depending on the material.

<Blocking layer: hole blocking layer, electron blocking layer>
The blocking layer is provided as necessary in addition to the basic constituent layer of the organic compound thin film as described above. For example, it is described in JP-A Nos. 11-204258 and 11-204359, and “Organic EL elements and the forefront of industrialization (published by NTT Corporation on November 30, 1998)” on page 237. There is a hole blocking (hole blocking) layer.

The hole blocking layer has a function of an electron transport layer in a broad sense, and is made of a hole blocking material that has a function of transporting electrons and has a remarkably small ability to transport holes. The probability of recombination of electrons and holes can be improved by blocking. Moreover, the structure of the electron carrying layer mentioned later can be used as a hole-blocking layer concerning this invention as needed. The hole blocking layer is preferably provided adjacent to the light emitting layer.

On the other hand, the electron blocking layer has a function of a hole transport layer in a broad sense, and is made of a material that has a function of transporting holes and has an extremely small ability to transport electrons, and transports electrons while transporting holes. By blocking, the recombination probability of electrons and holes can be improved. Moreover, the structure of the positive hole transport layer mentioned later can be used as an electron blocking layer as needed. The film thickness of the hole blocking layer and the electron transport layer according to the present invention is preferably 3 nm or more and 100 nm or less, and more preferably 5 nm or more and 30 nm or less.

《Hole transport layer》
The hole transport layer is made of a hole transport material having a function of transporting holes, and in a broad sense, a hole injection layer and an electron blocking layer are also included in the hole transport layer. The hole transport layer can be provided as a single layer or a plurality of layers.

The hole transport material has either hole injection or transport or electron barrier properties, and may be either organic or inorganic. For example, triazole derivatives, oxadiazole derivatives, imidazole derivatives, polyarylalkane derivatives, pyrazoline derivatives and pyrazolone derivatives, phenylenediamine derivatives, arylamine derivatives, amino-substituted chalcone derivatives, oxazole derivatives, styrylanthracene derivatives, fluorenone derivatives, hydrazone derivatives, Examples thereof include stilbene derivatives, silazane derivatives, aniline copolymers, and conductive polymer oligomers, particularly thiophene oligomers.

The above-mentioned materials can be used as the hole transport material, but it is preferable to use a porphyrin compound, an aromatic tertiary amine compound and a styrylamine compound, particularly an aromatic tertiary amine compound.

Representative examples of aromatic tertiary amine compounds and styrylamine compounds include N, N, N ′, N′-tetraphenyl-4,4′-diaminophenyl; N, N′-diphenyl-N, N′— Bis (3-methylphenyl)-[1,1′-biphenyl] -4,4′-diamine (TPD); 2,2-bis (4-di-p-tolylaminophenyl) propane; 1,1-bis (4-di-p-tolylaminophenyl) cyclohexane; N, N, N ′, N′-tetra-p-tolyl-4,4′-diaminobiphenyl; 1,1-bis (4-di-p-tolyl) Aminophenyl) -4-phenylcyclohexane; bis (4-dimethylamino-2-methylphenyl) phenylmethane; bis (4-di-p-tolylaminophenyl) phenylmethane; N, N'-diphenyl-N, N ' Di (4-methoxyphenyl) -4,4'-diaminobiphenyl; N, N, N ', N'-tetraphenyl-4,4'-diaminodiphenyl ether; 4,4'-bis (diphenylamino) quadriphenyl N, N, N-tri (p-tolyl) amine; 4- (di-p-tolylamino) -4 '-[4- (di-p-tolylamino) styryl] stilbene; 4-N, N-diphenylamino -(2-diphenylvinyl) benzene; 3-methoxy-4'-N, N-diphenylaminostilbenzene; N-phenylcarbazole, and also two described in US Pat. No. 5,061,569 Having a condensed aromatic ring of, for example, 4,4′-bis [N- (1-naphthyl) -N-phenylamino] biphenyl (NPD), JP-A-4-30 4,4 ′, 4 ″ -tris [N- (3-methylphenyl) -N-phenylamino] triphenylamine in which three triphenylamine units described in Japanese Patent No. 688 are linked in a starburst type ( MTDATA) and the like.

Further, a polymer material in which these materials are introduced into a polymer chain or these materials are used as a polymer main chain can also be used. In addition, inorganic compounds such as p-type-Si and p-type-SiC can also be used as the hole injection material and the hole transport material.

Also, JP-A-11-251067, J. Org. Huang et. al. A so-called p-type hole transport material described in a book (Applied Physics Letters, 80 (2002), p. 139) can also be used. In the present invention, it is preferable to use these materials because a light-emitting element with higher efficiency can be obtained.

The hole transport layer can be formed by thinning the hole transport material by a known method such as a vacuum deposition method, a spin coating method, a casting method, a printing method including an ink jet method, or an LB method. it can. Although there is no restriction | limiting in particular about the film thickness of a positive hole transport layer, Usually, 5 nm or more and about 5 micrometers or less, Preferably they are 5 nm or more and 200 nm or less. The hole transport layer may have a single layer structure composed of one or more of the above materials.

It is also possible to use a hole transport layer having a high p property doped with impurities. Examples thereof include JP-A-4-297076, JP-A-2000-196140, 2001-102175, J.A. Appl. Phys. 95, 5773 (2004), and the like.

In the present invention, it is preferable to use a hole transport layer having such a high p property because a device with lower power consumption can be produced.

《Electron transport layer》
The electron transport layer is made of a material having a function of transporting electrons, and in a broad sense, an electron injection layer and a hole blocking layer are also included in the electron transport layer. The electron transport layer can be provided as a single layer or a plurality of layers.

Conventionally, in the case of a single electron transport layer and a plurality of layers, an electron transport material (also serving as a hole blocking material) used for an electron transport layer adjacent to the light emitting layer on the cathode side is injected from the cathode. As long as it has a function of transferring electrons to the light-emitting layer, any material can be selected and used from among conventionally known compounds. For example, nitro-substituted fluorene derivatives, diphenylquinone derivatives Thiopyrandioxide derivatives, carbodiimides, fluorenylidenemethane derivatives, anthraquinodimethane and anthrone derivatives, oxadiazole derivatives and the like. Furthermore, in the above oxadiazole derivative, a thiadiazole derivative in which the oxygen atom of the oxadiazole ring is substituted with a sulfur atom, and a quinoxaline derivative having a quinoxaline ring known as an electron withdrawing group can also be used as an electron transport material. Furthermore, a polymer material in which these materials are introduced into a polymer chain or these materials are used as a polymer main chain can also be used.

In addition, metal complexes of 8-quinolinol derivatives such as tris (8-quinolinol) aluminum (Alq ₃ ), tris (5,7-dichloro-8-quinolinol) aluminum, tris (5,7-dibromo-8-quinolinol) Aluminum, tris (2-methyl-8-quinolinol) aluminum, tris (5-methyl-8-quinolinol) aluminum, bis (8-quinolinol) zinc (Znq), etc., and the central metals of these metal complexes are In, Mg Metal complexes replaced with Cu, Ca, Sn, Ga, or Pb can also be used as electron transport materials. In addition, metal-free or metal phthalocyanine, or those having terminal ends substituted with an alkyl group or a sulfonic acid group can be preferably used as the electron transporting material. Further, the distyrylpyrazine derivatives exemplified as the material of the light emitting layer can also be used as the electron transport material, and inorganic semiconductors such as n-type-Si and n-type-SiC can be used as well as the hole injection layer and the hole transport layer. It can be used as an electron transport material.

The electron transport layer can be formed by thinning the electron transport material by a known method such as a vacuum deposition method, a spin coating method, a casting method, a printing method including an ink jet method, or an LB method. Although there is no restriction | limiting in particular about the film thickness of an electron carrying layer, Usually, 5 nm or more and about 5 micrometers or less are preferable, Preferably they are 5 nm or more and 200 nm or less. The electron transport layer may have a single layer structure composed of one or more of the above materials.

It is also possible to use an electron transport layer having a high n property doped with impurities. Examples thereof include JP-A-4-297076, JP-A-10-270172, JP-A-2000-196140, 2001-102175, J.A. Appl. Phys. 95, 5773 (2004), and the like.

In the present invention, it is preferable to use an electron transport layer having such a high n property because an element with lower power consumption can be produced.

《Support substrate》
The support substrate (hereinafter also referred to as a substrate, substrate, substrate, support, etc.) is not particularly limited in the type of glass, plastic and the like, and may be transparent or opaque. When extracting light from the support substrate side, the support substrate is preferably transparent. Examples of the transparent support substrate preferably used include glass, quartz, and a transparent resin film. A particularly preferable support substrate is a resin film capable of giving flexibility to the organic EL element.

Examples of the resin film include polyesters such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), polyethylene, polypropylene, cellophane, cellulose diacetate, cellulose triacetate, cellulose acetate butyrate, cellulose acetate propionate (CAP), Cellulose esters such as cellulose acetate phthalate and cellulose nitrate or their derivatives, polyvinylidene chloride, polyvinyl alcohol, polyethylene vinyl alcohol, syndiotactic polystyrene, polycarbonate, norbornene resin, polymethylpentene, polyether ketone, polyimide, polyether Sulfone (PES), polyphenylene sulfide, polysulfones, polyester Examples include cycloolefin resins such as terimide, polyether ketone imide, polyamide, fluororesin, nylon, polymethyl methacrylate, acrylic or polyarylate, Arton (trade name, manufactured by JSR) or Appel (trade name, manufactured by Mitsui Chemicals). It is done.

An inorganic or organic film or a hybrid film of both may be formed on the surface of the resin film, and the water vapor transmission rate (40 ° C., 90%) measured by a method according to JIS-K-7129-1992. (RH) is preferably a barrier film of 0.01 g / (m ² · day · atm) or less, and moreover, oxygen permeability (20 ° C., measured by a method according to JIS-K-7126-1992) 100% RH) is ^{10 -3 g / (m 2 ·} day) or less, preferably water vapor permeability is ^{10 -3 g / (m 2 ·} day) or less of the high barrier film, wherein the water vapor transmission rate More preferably, the oxygen permeability is 10 ⁻⁵ g / (m ² · day) or less.

The material for forming the barrier film may be any material that has a function of suppressing intrusion of elements that cause deterioration of elements such as moisture and oxygen. For example, silicon oxide, silicon dioxide, silicon nitride, or the like can be used. Further, in order to improve the brittleness of the film, it is more preferable to have a laminated structure of these inorganic layers and organic material layers. Although there is no restriction | limiting in particular about the lamination | stacking order of an inorganic layer and an organic layer, It is preferable to laminate | stack both alternately several times.

<Method for forming barrier film>
The method for forming the barrier film is not particularly limited. For example, the vacuum deposition method, sputtering method, reactive sputtering method, molecular beam epitaxy method, cluster ion beam method, ion plating method, plasma polymerization method, atmospheric pressure plasma weight A combination method, a plasma CVD method, a laser CVD method, a thermal CVD method, a coating method, and the like can be used, but an atmospheric pressure plasma polymerization method as described in JP-A-2004-68143 is particularly preferable.

Examples of the opaque support substrate include metal plates / films such as aluminum and stainless steel, opaque resin substrates, ceramic substrates, and the like.

"anode"
As the anode in the organic EL element, an electrode material made of a metal, an alloy, an electrically conductive compound, or a mixture thereof having a high work function (4 eV or more) is preferably used. Specific examples of such electrode substances include metals such as Au, and conductive light-transmitting materials such as CuI, indium tin oxide (ITO), SnO ₂ , and ZnO. Alternatively, a material such as IDIXO (In ₂ O ₃ —ZnO) that can form an amorphous light-transmitting conductive film may be used. For the anode, these electrode materials may be formed into a thin film by a method such as vapor deposition or sputtering, and a pattern having a desired shape may be formed by a photolithography method, or when the pattern accuracy is not required (about 100 μm or more) ), A pattern may be formed through a mask having a desired shape when the electrode material is deposited or sputtered. Or when using the substance which can be apply | coated like an organic electroconductivity compound, wet film forming methods, such as a printing system and a coating system, can also be used. The sheet resistance as the anode is preferably several hundred Ω / □ or less. Further, although the film thickness depends on the material, it is usually selected in the range of 10 nm to 1000 nm, preferably 10 nm to 200 nm.

"cathode"
On the other hand, as the cathode, a material having a low work function (4 eV or less) metal (referred to as an electron injecting metal), an alloy, an electrically conductive compound, and a mixture thereof as an electrode material is used. Specific examples of such electrode materials include sodium, sodium-potassium alloy, magnesium, lithium, magnesium / copper mixture, magnesium / silver mixture, magnesium / aluminum mixture, magnesium / indium mixture, aluminum / aluminum oxide (Al ₂ O ₃ ) Mixtures, indium, lithium / aluminum mixtures, rare earth metals and the like.

Among these, from the point of durability against electron injection and oxidation, etc., a mixture of an electron injecting metal and a second metal which is a stable metal having a larger work function than this, for example, a magnesium / silver mixture, Magnesium / aluminum mixtures, magnesium / indium mixtures, aluminum / aluminum oxide (Al ₂ O ₃ ) mixtures, lithium / aluminum mixtures, aluminum and the like are preferred. The cathode can be produced by forming a thin film of these electrode materials by a method such as vapor deposition or sputtering. The sheet resistance as the cathode is preferably several hundred Ω / □ or less, and the film thickness is usually selected in the range of 10 nm to 5 μm, preferably 50 nm to 200 nm.

In addition, in order to transmit the emitted light, either the anode or the cathode of the organic EL element is configured to be light transmissive.

In the organic EL panel 100 described above, the anode 2 is disposed on the support substrate 1 and the cathode 4 is disposed with the organic functional layer 3 interposed therebetween. However, the first electrode is the cathode 4 and the second electrode is the anode 2. The arrangement of the anode 2 and the cathode 4 may be reversed.

<< Method for Manufacturing Organic EL Element >>
As an example of the method for producing an organic EL device, a method for producing an organic EL device comprising an anode / hole injection layer / hole transport layer / light emitting layer / hole blocking layer / electron transport layer / cathode will be described.

First, a desired electrode material, for example, a thin film made of an anode material is formed on a suitable support substrate by a method such as vapor deposition or sputtering so as to have a film thickness of 1 μm or less, preferably 10 nm or more and 200 nm or less, and an anode is manufactured. To do. Next, an organic compound thin film of a hole injection layer, a hole transport layer, a light emitting layer, a hole blocking layer, and an electron transport layer, which are organic EL element materials, is formed thereon.

As a method for thinning the organic compound thin film, there are a vapor deposition method and a wet process (spin coating method, casting method, ink jet method, printing method) as described above, but it is easy to obtain a uniform film and a pinhole. From the point of being difficult to form, a vacuum deposition method, a spin coating method, an inkjet method, and a printing method are particularly preferable. Further, a different film forming method may be applied for each layer. When a vapor deposition method is employed for film formation, the vapor deposition conditions vary depending on the type of compound used, but generally the boat heating temperature is 50 to 450 ° C., the degree of vacuum is 10 ^{−6 to} 10 ⁻² Pa and the vapor deposition rate is 0. It is desirable to select appropriately within the range of 01 nm / second to 50 nm / second, substrate temperature −50 ° C. to 300 ° C., and film thickness 0.1 nm to 5 μm, preferably 5 nm to 200 nm.

After these layers are formed, a thin film made of a cathode material is formed thereon by a method such as vapor deposition or sputtering so as to have a film thickness of 1 μm or less, preferably 50 nm or more and 200 nm or less. By providing, a desired organic EL element can be obtained. The organic EL element is preferably produced from the hole injection layer to the cathode consistently by a single evacuation, but may be taken out halfway and subjected to different film forming methods. At that time, it is necessary to consider that the work is performed in a dry inert gas atmosphere.

It is also possible to reverse the production order to produce a cathode, an electron injection layer, an electron transport layer, a light emitting layer, a hole transport layer, a hole injection layer, and an anode in this order. When a DC voltage is applied to the multi-color liquid crystal display device thus obtained, light emission can be observed by applying a voltage of about 2 V to 40 V with the positive polarity of the anode and the negative polarity of the cathode. An alternating voltage may be applied. The alternating current waveform to be applied may be arbitrary.

An organic EL element emits light within a layer having a refractive index higher than that of air (refractive index: 1.6 to 2.1), and only 15% to 20% of light generated in the light emitting layer can be extracted. It is generally said that there is no. This is because light incident on the interface (interface between the transparent substrate and air) at an angle θ greater than the critical angle causes total reflection and cannot be extracted outside the device, or between the transparent electrode or light emitting layer and the transparent substrate. This is because the light is totally reflected between the light and the light is guided through the transparent electrode or the light emitting layer, and as a result, the light escapes in the direction of the element side surface.

As a method for improving the light extraction efficiency, for example, a method of forming irregularities on the surface of the transparent substrate to prevent total reflection at the interface between the transparent substrate and the air (for example, US Pat. No. 4,774,435). ), A method of improving the efficiency by giving the substrate a light condensing property (for example, JP-A-63-314795), a method of forming a reflective surface on the side surface of the element (for example, JP-A-1-220394) Gazette), a method of forming an antireflection film by introducing a flat layer having an intermediate refractive index between the substrate and the light emitter (for example, Japanese Patent Application Laid-Open No. 62-172691), a substrate between the substrate and the light emitter. A method of introducing a flat layer having a lower refractive index than that (for example, Japanese Patent Laid-Open No. 2001-202827), a diffraction grating is provided between any of the substrate, the transparent electrode layer and the light emitting layer (including between the substrate and the outside). Method of forming There is 11-283751 JP), and the like.

In the present invention, these methods can be used in combination, but either a method of introducing a flat layer having a lower refractive index than the substrate between the substrate and the light emitter, or any of the substrate, the transparent electrode layer, and the light emitting layer. A method of forming a diffraction grating between the layers (including between the substrate and the outside) can be suitably used. In the present invention, by combining these means, it is possible to obtain an element having higher luminance or durability.

When a medium having a low refractive index is formed between the transparent electrode and the transparent substrate with a thickness longer than the wavelength of light, the efficiency of taking out the light from the transparent electrode to the outside increases as the refractive index of the medium decreases.

Examples of the low refractive index layer include aerogel, porous silica, magnesium fluoride, and a fluorine-based polymer. Since the refractive index of the transparent substrate is generally about 1.5 or more and 1.7 or less, the low refractive index layer preferably has a refractive index of about 1.5 or less. Furthermore, it is preferable that it is 1.35 or less.

Also, the thickness of the low refractive index medium is preferably at least twice the wavelength in the medium. This is because the effect of the low-refractive index layer is reduced when the thickness of the low-refractive index medium is about the wavelength of light and the electromagnetic wave exuded by evanescent enters the substrate.

The method of introducing a diffraction grating into an interface or any medium that causes total reflection is characterized by a high effect of improving light extraction efficiency. This method uses the property that the diffraction grating can change the direction of light to a specific direction different from refraction by so-called Bragg diffraction, such as first-order diffraction and second-order diffraction. Among them, light that cannot be emitted due to total reflection between layers, etc. is diffracted by introducing a diffraction grating into any layer or medium (in a transparent substrate or transparent electrode), and the light is emitted outside. I want to take it out.

It is desirable that the diffraction grating to be introduced has a two-dimensional periodic refractive index. This is because light emitted from the light-emitting layer is randomly generated in all directions, so in a general one-dimensional diffraction grating having a periodic refractive index distribution only in a certain direction, only light traveling in a specific direction is diffracted. In other words, the light extraction efficiency does not increase so much. However, by making the refractive index distribution a two-dimensional distribution, light traveling in all directions is diffracted, and light extraction efficiency is increased.

As described above, the position where the diffraction grating is introduced may be in any of the layers or in the medium (in the transparent substrate or in the transparent electrode), but is preferably in the vicinity of the organic light emitting layer where light is generated.

At this time, the period of the diffraction grating is preferably about 1/2 to 3 times the wavelength of the light in the medium. The arrangement of the diffraction grating is preferably two-dimensionally repeated such as a square lattice, a triangular lattice, or a honeycomb lattice.

The organic EL element of the present invention is processed on the light extraction side of the support substrate, for example, so as to provide a structure on a microlens array, or combined with a so-called condensing sheet, for example, in a specific direction, for example, the element light emitting surface. On the other hand, the brightness | luminance in a specific direction can be raised by condensing in a front direction.

As an example of a microlens array, quadrangular pyramids having a side of 30 μm and an apex angle of 90 degrees are arranged two-dimensionally on the light extraction side of the substrate. One side is preferably 10 to 100 μm. If it becomes smaller than this, the effect of diffraction will generate | occur | produce and color, and if too large, thickness will become thick and is not preferable.

As the condensing sheet, it is possible to use, for example, a sheet that has been put to practical use in an LED backlight of a liquid crystal display device. As such a sheet, for example, a brightness enhancement film (BEF) manufactured by Sumitomo 3M Limited can be used. As the shape of the prism sheet, for example, the base material may be formed by forming a △ -shaped stripe having a vertex angle of 90 degrees and a pitch of 50 μm, or the vertex angle is rounded and the pitch is changed randomly. Other shapes may be used.

Further, in order to control the light emission angle from the organic EL element, a light diffusion plate / film may be used in combination with the light collecting sheet. For example, a diffusion film (light-up) manufactured by Kimoto Co., Ltd. can be used.

[Second Embodiment]
The organic EL panel 100 of the first embodiment includes the first to third sealing members 7 to 9, but the first and second sealings as in the organic EL panel 100A described below. It is good also as a structure provided with member 7A, 8A.
FIG. 3 is a cross-sectional view of the organic EL panel.
As shown in FIG. 3, the first sealing member 7A and the second sealing member 8A are disposed on the organic EL element 10A via the first adhesive layer 5A. That is, the first adhesive layer 5A is formed on the exposed upper surfaces of the anode 2A, the organic functional layer 3A, and the cathode 4A, and the second sealing member 8A that is linear in a side view is formed on the first adhesive layer 5A. And the left side ends of the cathode 4A, the organic functional layer 3A, and the anode 2A are exposed.
Further, the second adhesive layer 6A is formed on the upper surface of the second sealing member 8A except the right end portion.
The first sealing member 7A includes the anode 2A, the organic functional layer 3A, and the cathode on the portion of the first adhesive layer 5A where the second sealing member 8A is not provided and the second adhesive layer 6A. 4A covers the left end portion of 4A, covers a part of the second sealing member 8A so as not to contact the left end portion of the second sealing member 8A, and the right end portion of the second sealing member 8A It is provided to be exposed.
Thus, in the organic EL panel 100A, the first and second sealing members 7A and 8A are disposed so as not to be in electrical contact with each other via the first and second adhesive layers 5A and 6A. The organic EL element 10A has a sealing structure sealed with the first and second sealing members 7A and 8A.

The first and second sealing members 7A and 8A have substantially the same size, and are supported when the support substrate 1A and the first and second sealing members 7A and 8A are viewed in plan. The outer shape of the substrate 1A and the entire first and second sealing members 7A and 8A have the same dimensions.
Further, the size of the first sealing member 7A may be further increased. In this case, since the distance from the right end portion of the first sealing member 7A to the left end portion of the second sealing member 8A can be increased, the sealing function can be enhanced.

The left end of the anode 2A and the left end of the first sealing member 7A are electrically connected by the above-described electrical connection method. The right end of the cathode 4A and the right end of the second sealing member 8A are also electrically connected by the above-described electrical connection method. In FIG. 3, the conductive fillers 14A are dispersed in the first adhesive layer 5A to be electrically connected.
The anode power supply portion 11A is formed on the upper surface of the first sealing member 7A, and the cathode power supply portion 12A is formed on the upper surface of the second sealing member 8A. The anode power supply portion 11A and the cathode power supply portion 11A are formed. The power feeding part 12A is provided outside the first and second adhesive layers 5A and 6A.

As described above, also in the second embodiment, similarly to the first embodiment, the anode 2A and the cathode 4A are electrically connected to the first and second sealing members 7A and 8A, respectively. Therefore, the anode power supply part 11A and the cathode power supply part 12A can be provided on the surfaces of the first and second sealing members 7A, 8A opposite to the support substrate 1A. As a result, since it is not necessary to provide the anode and cathode power supply portions on the support substrate 1A as in the prior art, the non-light emitting area in the plan view of the organic EL element 10A can be reduced, and a large power supply area is ensured. Therefore, the wiring can be easily connected and the cost can be reduced.
Further, when the support substrate 1A and the entire first and second sealing members 7A and 8A are viewed in plan, the outer shape of the support substrate 1A and the entire first and second sealing members 7A and 8A are displayed. Is the same size, so it looks good and the overall strength of the panel increases. Further, by making the outer shape of the support substrate 1A and the first and second sealing members 7A, 8A the same size, the area for sealing the organic EL element 10A is increased, so that the organic Moisture and oxygen intrusion into the EL element 10A can be reliably suppressed, and the life of the organic EL element 10A can be improved.
Furthermore, in the second embodiment, since the structure is sealed by the first and second sealing members 7A and 8A, the number of members can be reduced and the cost can be reduced as compared with the first embodiment. be able to.
In addition, since the organic EL element 10A has a sealing structure covered with the first and second sealing members 7A and 8A, moisture and oxygen ingress can be reliably suppressed in this respect as well.
Note that the present invention is not limited to the above embodiment, and can be modified as appropriate. In the following description, the same parts as those in the above embodiment are denoted by the same reference numerals and the description thereof is omitted. For example, in the first embodiment, the third sealing member 9 and the second adhesive layer 6 are provided, but these are not necessarily provided.

The present invention can be suitably used for an organic electroluminescence panel capable of reducing a non-light emitting area in a plan view and a method for manufacturing the organic electroluminescence panel.

1, 1A, 21 Support substrate 2, 2A, 22 Anode 3, 3A, 23 Organic functional layer 4, 4A, 24 Cathode 5, 5A First adhesive layer 6, 6A Second adhesive layer 7, 7A First sealing member 8, 8A Second sealing member 9 Third sealing member 10, 10A, 20 Organic EL element 11, 11A Anode feeding portion 12, 12A Cathode feeding portion 13 Solder 14, 14A Conductive filler 25 Adhesive layer 27 Sealing Stopping member 28 Anode feeding portion 29 Cathode feeding portion 100, 100A Organic EL panel S Gap

Claims (10)

1. An organic electroluminescent element in which at least a first electrode, a light emitting layer, and a second electrode are formed in this order on a support substrate is provided with a conductive sealing layer via an insulating adhesive layer provided on the second electrode. An organic electroluminescence panel sealed with a stop member,
   A plurality of the conductive sealing members are provided,
   The organic electroluminescence panel, wherein the first electrode and the second electrode are electrically connected to different conductive sealing members among the plurality of conductive sealing members.
2. On the surface opposite to the support substrate of the conductive sealing member electrically connected to the first electrode, a power feeding portion for the first electrode is provided,
   2. The power feeding portion for the second electrode is provided on a surface opposite to the support substrate of the conductive sealing member electrically connected to the second electrode. The organic electroluminescence panel described.
3. The plurality of conductive sealing members are provided with an insulating adhesive layer between the conductive sealing members,
   The organic electroluminescence panel according to claim 2, wherein the first electrode power supply unit and the second electrode power supply unit are provided outside the insulating adhesive layer.
4. The conductive sealing member provided with the power feeding portion for the first electrode and the conductive sealing member provided with the power feeding portion for the second electrode are spaced apart from each other on the same plane. Arranged,
   The other conductive sealing member is laminated | stacked through the said insulating contact bonding layer on the clearance gap between the said conductive sealing members mutually adjacent on the same plane. Organic electroluminescence panel.
5. The first electrode and the second electrode are in the insulating adhesive layer provided on the second electrode with respect to the different conductive sealing members among the plurality of conductive sealing members. The organic electroluminescence panel according to any one of claims 1 to 4, wherein the organic electroluminescence panel is electrically connected via a dispersed conductive filler.
6. When the support substrate and the plurality of conductive sealing members are viewed in plan, the outer shape of the support substrate and the plurality of conductive sealing members are the same size. The organic electroluminescence panel according to any one of claims 1 to 5.
7. An organic electroluminescent element in which at least a first electrode, a light emitting layer, and a second electrode are formed in this order on a support substrate is provided with a conductive sealing layer via an insulating adhesive layer provided on the second electrode. An organic electroluminescence panel manufacturing method for manufacturing an organic electroluminescence panel sealed by a stop member,
   A plurality of the conductive sealing members are provided,
   The method for producing an organic electroluminescence panel, wherein the first electrode and the second electrode are electrically connected to different conductive sealing members among the plurality of conductive sealing members. .
8. The first electrode and the second electrode are joined and electrically connected by laser welding to different conductive sealing members among the plurality of conductive sealing members. The manufacturing method of the organic electroluminescent panel of Claim 7.
9. The first electrode and the second electrode are joined and electrically connected by ultrasonic welding to different conductive sealing members among the plurality of conductive sealing members. The manufacturing method of the organic electroluminescent panel of Claim 7.
10. The first electrode and the second electrode are joined by caulking and electrically connected to different conductive sealing members among the plurality of conductive sealing members. Item 8. A method for producing an organic electroluminescence panel according to Item 7.

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