WO2013051358A1

WO2013051358A1 - Organic electroluminescence element, planar light-emitting body, and method for manufacturing organic electroluminescence element

Info

Publication number: WO2013051358A1
Application number: PCT/JP2012/072434
Authority: WO
Inventors: 小島　茂; 源田　和男
Original assignee: コニカミノルタホールディングス株式会社
Priority date: 2011-10-04
Filing date: 2012-09-04
Publication date: 2013-04-11
Also published as: JPWO2013051358A1

Abstract

Provided is an organic EL element in which the non-light-emitting region is reduced and the performance and quality can be improved. An organic EL element (10) configured so as to be provided with: a first through-hole electrode (7) provided to a part of a region of either an insulating sealing material (5) or an element base material (1) facing a first electrode (2), the first through-hole electrode being provided so as to penetrate the member in the thickness direction of the member, and the tip of the first through-hole electrode being in contact with the first electrode (2); and a second through-hole electrode (8) provided to a part of a region of said member facing second electrodes (4), (4a), the second through-hole electrode being provided so as to penetrate the member in the thickness direction of the member, and the tip of the second through-hole electrode being in contact with the second electrode (4).

Description

ORGANIC ELECTROLUMINESCENT ELEMENT, SURFACE LIGHT EMITTER, AND METHOD FOR PRODUCING ORGANIC ELECTROLUMINESCENT ELEMENT

The present invention relates to an organic electroluminescence device, a planar light emitter, and a method for manufacturing an organic electroluminescence device.

An organic electroluminescent element is an element using electroluminescence of an organic material (hereinafter referred to as an organic EL element), and mainly includes an anode, a cathode, and an organic light emitting functional layer provided between the anode and the cathode. Composed. In the organic EL element having such a configuration, light generated in the organic light emitting functional layer (hereinafter referred to as light emission) is extracted from the surface of the anode or the cathode, so that uniform illumination can be obtained on the emission surface. In addition, since organic EL elements can obtain emitted light that does not contain ultraviolet rays, a light source that is gentle to the eyes can be obtained. Furthermore, since an organic EL element does not contain a harmful metal, it is an element with high environmental suitability. From the above, recently, organic EL elements are promising as planar light emitters in applications such as display devices and lighting devices (displays).

Incidentally, the organic EL element normally seals the organic light emitting functional layer using a sealing member in order to prevent deterioration due to the ingress of active gas or moisture. For this reason, a sealing region is provided at the peripheral portion of the organic EL element, and a non-light emitting region in which the organic light emitting functional layer is not disposed is formed. Furthermore, since the organic EL element is also provided with a power supply terminal region for supplying power to the anode and the cathode, a non-light emitting region in which the organic light emitting functional layer is not disposed is also formed in the power supply terminal region.

When such a non-light-emitting region is increased, the area of the light-emitting region is reduced with respect to the installation area of the organic EL element (area of the element substrate), so that the installation efficiency is reduced and the cost is increased. Moreover, when a planar light-emitting body is configured by arranging a plurality of organic EL elements, a non-light-emitting region appears as a dark line, causing a problem that the above-described advantage of uniform illumination is impaired. Furthermore, when a planar light emitter is configured by arranging a plurality of organic EL elements, there is a problem that the non-light emitting region becomes large and the appearance is deteriorated. Therefore, conventionally, various techniques for solving such problems have been proposed (see, for example, Patent Document 1).

In Patent Document 1, in an organic EL element in which a first electrode (anode), an organic layer, a second electrode (cathode), and a sealing film are stacked in this order on a substrate, a part of the sealing film is provided with a first There has been proposed a technique in which one terminal is provided and the first terminal and the first electrode are connected by a through hole penetrating the organic layer, the second electrode, and the sealing film. In Patent Document 1, an opening is provided in a part of the sealing film formed on the second electrode, and the second electrode exposed in the opening is used as the second terminal. In Patent Document 1, the non-light emitting region is reduced by adopting such an electrode configuration.

JP 2005-158371 A

As described above, conventionally, various techniques for reducing the non-light-emitting region have been proposed for organic EL elements and planar light emitters using the same. However, in this technical field, there is a demand for the development of a technology that not only reduces the non-light-emitting region, but also realizes high performance and high quality at the same time.

The present invention has been made to meet the above-mentioned demands, and an object of the present invention is to reduce the non-light emitting region and improve the performance and quality, an organic EL element, a planar light emitter, and It is providing the manufacturing method of an organic EL element.

In order to solve the above problems, an organic EL device of the present invention includes an element substrate, a first electrode formed on the element substrate, an organic compound formed on the first electrode and including a light emitting layer. A layer, a second electrode formed on the organic compound layer, and an insulating sealing material provided to cover the surface of the element base on the second electrode side. Furthermore, the organic EL element of the present invention is provided in a part of a region facing the first electrode of one member of the insulating sealing material and the element base material so as to penetrate in the thickness direction of the member, and A first through-hole electrode whose tip is in contact with the first electrode, and a part of a region of the member facing the second electrode, which is provided so as to penetrate in the thickness direction of the member; The second through-hole electrode is in contact with the two electrodes.

The planar light-emitting body of the present invention includes a plurality of the organic EL elements of the present invention and a support member that supports the plurality of organic EL elements arranged in a predetermined form.

Furthermore, the manufacturing method of the organic EL element of this invention shall be performed in the following procedure. First, the first electrode is formed on the element substrate. Next, an organic compound layer including a light emitting layer is formed on the first electrode. Next, a second electrode is formed on the organic compound layer. Next, an insulating sealing material for sealing the surface of the element base on the second electrode side, a part of the region facing the first electrode of one member of the element base, and the first of the member A first through hole and a second through hole are formed in a part of the region facing the two electrodes, respectively. Next, a first through-hole electrode having a shape extending along the thickness direction of the member and protruding from the surface of the member on the organic compound layer side and electrically connected to the first electrode and the second electrode, respectively The second through-hole electrode is formed to seal the first through-hole and the second through-hole, respectively. Moreover, in the manufacturing method of the organic EL element of this invention, an insulating sealing material is provided on an element base material so that the surface by the side of the 2nd electrode of an element base material may be sealed.

As described above, in the organic EL element of the present invention, the first through-hole electrode and the second through-hole electrode that are in contact with the first electrode and the second electrode, respectively, on one member of the insulating sealing material and the element base material. Is provided. That is, in the organic EL element of the present invention, the first through-hole electrode and the second through-hole electrode are used as power supply terminals. Therefore, in the present invention, the non-light emitting region can be reduced.

Moreover, in the organic EL element of the present invention, the first through-hole electrode and the second through-hole electrode act as a part of the sealing member. Therefore, in the present invention, an organic EL element having excellent moisture resistance can be provided.

As described above, according to the organic EL element, the planar light emitter, and the method for producing the organic EL element of the present invention, the non-light emitting region can be reduced and the performance and quality can be improved.

FIG. 1 is a schematic cross-sectional view of an organic EL element according to an embodiment of the present invention. FIG. 2 is a diagram illustrating a configuration example of the organic light emitting functional layer. FIG. 3 is a diagram showing the relationship between the sealing margin and the dark spot generation area. FIG. 4 is a schematic cross-sectional view of a planar light emitter according to an embodiment of the present invention. FIG. 5 is a schematic cross-sectional view of the organic EL element of Modification 1. FIG. 6 is a schematic cross-sectional view of an organic EL element according to Modification 2. FIG. 7 is a schematic cross-sectional view of an organic EL element of Modification 3. FIG. 8 is a schematic cross-sectional view of the element main body in the organic EL element of Example 1. 9A and 9B are diagrams for explaining a method for manufacturing the organic EL element of Example 1. FIG. 10A and 10B are diagrams for explaining a method for manufacturing the organic EL element of Example 1. FIG. 11A and 11B are diagrams for explaining a method for manufacturing the organic EL element of Example 1. FIG. 12A and 12B are diagrams for explaining a method for manufacturing the organic EL element of Example 1. FIG. FIG. 13 is a diagram illustrating a light emitting region of the organic EL element of Example 1. FIG. 14A and 14B are diagrams for explaining a method of manufacturing the organic EL element of Example 1. FIG. 15A and 15B are diagrams for explaining a method for manufacturing the organic EL element of Example 1. FIG. 16A and 16B are diagrams for explaining a method for manufacturing the organic EL element of Example 1. FIG. FIG. 17 is a diagram for explaining a method for manufacturing the organic EL element of Example 1. FIG. 18A and 18B are schematic configuration diagrams of a sealing substrate of Example 2. FIG. FIG. 19 is a schematic cross-sectional view of a sealing substrate on which through-hole electrodes are formed in Example 2. FIG. 20 is a schematic configuration diagram of a sealing substrate of a comparative example. FIG. 21 is a schematic cross-sectional view of a sealing substrate on which through-hole electrodes of Example 6 are formed. FIG. 22 is a schematic cross-sectional view of a sealing substrate on which through-hole electrodes of Example 7 are formed.

Hereinafter, an example of a method for manufacturing an organic EL element, a planar light emitter, and an organic EL element according to an embodiment of the present invention will be described in detail with reference to the drawings. It is not limited to.

<1. Configuration of organic EL element>
[Overall configuration of organic EL element]
In FIG. 1, the structural example of the organic EL element which concerns on one Embodiment of this invention is shown. FIG. 1 is a schematic cross-sectional view of the organic EL element of the present embodiment.

The organic EL element 10 includes an element substrate 1 (element base), an anode 2 (first electrode), an organic light emitting functional layer 3 (organic compound layer), a cathode 4 (second electrode), and a cathode lead electrode 4a. A sealing base material 5 (insulating sealing material), a sealing material 6 (adhesive material), an anode through-hole electrode 7 (first through-hole electrode), and a cathode through-hole electrode 8 (second through-hole). Hall electrode).

In the present embodiment, the anode 2, the organic light emitting functional layer 3, and the cathode 4 are laminated on the element substrate 1 in this order. That is, on the element substrate 1, the anode 2 and the cathode 4 are configured by the organic light emitting functional layer 3 in a state in which insulation is maintained. The cathode lead electrode 4 a is formed in a region different from the anode 2 on the surface of the element substrate 1. Further, a part of the cathode 4 is formed on a partial region of the cathode lead electrode 4a. As a result, the cathode 4 is electrically connected to the cathode lead electrode 4a.

In addition, the organic EL element 10 of the present embodiment is an organic EL element manufactured by a solid adhesion sealing type sealing method, and the sealing substrate 5 is a cathode of the element substrate 1 through the sealing material 6. It is fixed over the entire surface on the 4 side. By adopting such a sealing form, the contact portion between the through-hole electrode and the corresponding electrode film is protected on the inner side of the sealing material, so that deterioration with time can be suppressed.

In the present embodiment, as described above, the inside of the organic EL element 10 is sealed with the sealing base material 5 in order to prevent the deterioration of the organic light emitting functional layer 3. In addition, a space for sealing the organic EL element is provided, and the organic light emitting functional layer 3 is disposed at the approximate center of the element substrate 1.

The anode through-hole electrode 7 is a vertical hole electrode formed through the sealing substrate 5 and the sealing material 6 in the thickness direction of the organic EL element 10, and is provided near the outer peripheral end of the anode 2. It is formed on the region of the extraction electrode portion. The anode through-hole electrode 7 is formed of a conductive material, and extends from the surface of the sealing substrate 5 opposite to the sealing material 6 side to the surface of the anode 2. At this time, one end portion (upper portion in FIG. 1) of the anode through-hole electrode 7 is formed so as to be exposed on the surface of the sealing substrate 5 opposite to the sealing material 6 side, and the other end portion ( In FIG. 1, the lower part (tip) is formed so as to contact the anode 2. As a result, the anode through-hole electrode 7 is electrically connected to the anode 2.

In the present embodiment, as shown in FIG. 1, the shape of the anode through-hole electrode 7 is substantially conical and the tip surface thereof is a flat surface (hereinafter referred to as a truncated cone shape). An example is shown. Moreover, in this embodiment, the diameter of the anode through-hole electrode 7 shows an example in which the diameter gradually decreases from the sealing substrate 5 toward the anode 2.

The cathode through-hole electrode 8 is a vertical hole electrode formed through the sealing substrate 5 and the sealing material 6 in the thickness direction of the organic EL element 10 in the same manner as the anode through-hole electrode 7. It is formed on the region of the cathode lead electrode 4a. The cathode through-hole electrode 8 is formed of a conductive material and extends from the surface of the sealing substrate 5 opposite to the sealing material 6 side to the surface of the cathode lead electrode 4a. At this time, one end portion (upper portion in FIG. 1) of the cathode through-hole electrode 8 is formed so as to be exposed on the surface of the sealing substrate 5 opposite to the sealing material 6 side, and the other end portion ( The lower part in FIG. 1 is formed in contact with the cathode lead electrode 4a. Thereby, the through-hole electrode 8 for cathodes is electrically connected with the cathode 4 via the cathode extraction electrode 4a.

In the present embodiment, as shown in FIG. 1, the shape of the cathode through-hole electrode 8 is the same as the shape of the anode through-hole electrode 7. Note that the present invention is not limited to this, and the configuration (shape, size, etc.) of the cathode through-hole electrode 8 is different from the configuration of the anode through-hole electrode 7 depending on conditions such as the use and surrounding wiring pattern. May be different.

FIG. 1 shows an example in which the anode 2, the organic light emitting functional layer 3 and the cathode 4 are formed in this order on the element substrate 1. However, the present invention is not limited to this, and the lamination of these layers is shown. The order may be reversed. However, when the organic EL element 10 is a bottom emission type element that extracts emitted light generated in the organic light emitting functional layer 3 from the element substrate 1 side, an electrode disposed on the element substrate 1 side of the organic light emitting functional layer 3 (One of the anode 2 and the cathode 4) is formed of a transparent electrode. In this case, the electrode (the other of the anode 2 and the cathode 4) disposed on the side opposite to the element substrate 1 side of the organic light emitting functional layer 3 is composed of an electrode (reflecting electrode) having light reflectivity.

In the organic EL element 10 of the present embodiment, the entire element substrate 1 is covered with the sealing base material 5 and two through

holes

5a and 5b are formed in the sealing base material 5 and then each through hole is sealed. Thus, through-hole electrodes are provided (filled) in the respective through-holes. At this time, the anode through-hole electrode 7 is provided in one through-hole 5a (first through-hole), and the cathode through-hole electrode 8 is provided in the other through-hole 5b (second through-hole). Provided. Then, the through-hole electrode is brought into contact (electrically connected) with the corresponding electrode film (anode 2 and cathode 4). That is, in the present embodiment, the through-hole electrode is used as a power supply terminal to the corresponding electrode film and also used as a part of the sealing member.

Therefore, in the organic EL element 10 of the present embodiment, it is not necessary to separately provide a power supply terminal area in the surface of the element substrate 1, and the non-light emitting area can be reduced. In this case, the non-light emitting region can be designed in consideration of only the sealing performance.

Further, in the present embodiment, the entire element substrate 1 is covered with the sealing base material 5 and the power feeding portion is sealed with the through-hole electrode. Therefore, in this embodiment, sufficient high temperature storage stability and high humidity storage stability can be ensured. Further, since the power supply terminal portion (electrode connection portion) is exposed on the outer surface of the sealing substrate 5, wiring from the power source can be easily connected, and an increase in drive voltage can be avoided. . That is, in the organic EL element 10 of the present embodiment, high temperature / high humidity storage stability can be maintained, an increase in driving voltage can be suppressed, and a non-light emitting region can be reduced.

The inventor has verified the method proposed in the above-mentioned Patent Document 1 using the through-hole electrode as the anode power supply terminal and the cathode region exposed at the opening of the sealing film as the cathode power supply terminal. As a result, it was found that it was difficult to maintain high temperature and high humidity storage stability with this configuration. It was also found that with this configuration, a good wiring connection to the power feeding portion could not be obtained, and the drive voltage increased. However, with the configuration of the present embodiment, problems that may occur in the technique described in Patent Document 1 can be solved.

Hereinafter, the configuration of each part and each layer of the organic EL element 10 will be described more specifically.

[Element substrate]
The element substrate 1 is a substrate that supports the anode 2, the cathode 4, and the organic light emitting functional layer 3. In the present embodiment, since the emitted light generated in the organic light emitting functional layer 3 is taken out from the element substrate 1 side, the element substrate 1 is formed of a material having high light transmittance with respect to visible light. For example, as the element substrate 1, a plate-like member such as a glass substrate, a quartz substrate, or a transparent resin film can be used.

Among these, as a material for forming the transparent resin film, for example, polyester such as polyethylene terephthalate (PET) or polyethylene naphthalate (PEN) can be used. Moreover, as a formation material of a transparent resin film, materials, such as polyethylene, a polypropylene, a cellophane, can be used, for example. In addition, cellulose esters such as cellulose diacetate, cellulose triacetate, cellulose acetate butyrate, cellulose acetate propionate (CAP), cellulose acetate phthalate (TAC), and cellulose nitrate, or derivatives thereof can be added to the transparent resin film. It can be used as a forming material.

Examples of the material for forming the transparent resin film include polyvinylidene chloride, polyvinyl alcohol, polyethylene vinyl alcohol, syndiotactic polystyrene, polycarbonate, norbornene resin, polymethylpentene, polyether ketone, polyimide, and polyether sulfone (PES). , Polyphenylene sulfide, polysulfones, polyether imide, polyether ketone imide, polyamide, fluororesin, nylon, polymethyl methacrylate, acrylic, polyarylate, and the like can be used. Furthermore, for example, cycloolefin-based resins called Arton (registered trademark: manufactured by JSR) or Apel (registered trademark: manufactured by Mitsui Chemicals) can be used as a material for forming a transparent resin film.

When the element substrate 1 is composed of a transparent resin film, the surface of the transparent resin film is formed of a barrier film made of an inorganic material or an organic material in order to suppress the transmission of, for example, water vapor or oxygen into the organic EL element 10. A barrier film or a hybrid film in which these barrier films are stacked may be provided.

The barrier film is preferably a barrier film having a water vapor permeability (measuring environment: 40 ° C., relative humidity 90% RH) of 0.01 g / (m ² · 24 h) or less. The barrier film has an oxygen permeability (measuring environment: 20 ° C., relative humidity 100% RH) of 10 ⁻³ cm ³ / (m ² · 24 h · atm) or less and a water vapor permeability of 10 ⁻³ g. / (M ² · 24h) or less is preferable. Furthermore, the water vapor permeability of the barrier film is 10 ⁻⁵ g / (m ² · 24 h) or less, and the oxygen permeability is particularly preferably 10 ⁻⁵ cm ³ / (m ² · 24 h · atm) or less. preferable. In this specification, “water vapor permeability” is a value measured by a method according to JIS-K-7129-1992, and “oxygen permeability” is according to JIS-K-7126-1992. It is a value measured by the method.

As the barrier film having the above-described characteristics, for example, an inorganic material film such as a silicon oxide film, a silicon dioxide film, or a silicon nitride film can be used. Furthermore, in order to improve the fragility of the barrier film, a hybrid barrier film in which the inorganic material film and the organic material film are stacked may be used as the barrier film. In this case, the order of laminating the inorganic material film and the organic material film is arbitrary, but it is preferable that the both are alternately laminated a plurality of times.

Also, as a method for forming the barrier film, any method can be used as long as it can form the barrier film on the element substrate 1 (transparent resin film). For example, 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 polymerization method (see JP 2004-68143 A), Techniques such as plasma CVD (Chemical Vapor Deposition), laser CVD, thermal CVD, and coating can be used. In the present embodiment, it is particularly preferable to use an atmospheric pressure plasma polymerization method.

[anode]
The anode 2 is an electrode film that supplies holes to the organic light emitting functional layer 3 and can be formed of a conductive material having a large work function (for example, 4 eV or more) that can exhibit a hole injection function. As such a conductive material, a metal, an alloy, an organic or inorganic conductive compound, and a mixture thereof are used. Specifically, light of metals such as gold (Au), copper iodide (CuI), indium tin oxide (SnO ₂ —In ₂ O ₃ : ITO), tin oxide (SnO ₂ ), zinc oxide (ZnO), etc. The anode 2 can be formed of a conductive material having transparency. The anode 2 can also be formed of an amorphous transparent electrode material such as IDIXO (registered trademark: In ₂ O ₃ —ZnO). In addition, when taking out emitted light from the anode 2 side, the anode 2 (transparent electrode) should just be formed using the light-transmitting conductive material among the above-mentioned materials.

The sheet resistance of the anode 2 is several hundred Ω / sq. The following is preferable. Further, the film thickness of the anode 2 is appropriately set according to the forming material, but is usually set in the range of about 10 to 1000 nm, preferably about 10 to 200 nm.

The anode 2 configured as described above can be formed on the element substrate 1 by a technique such as vapor deposition or sputtering. At this time, the anode 2 may be formed in a desired pattern shape using a photolithography technique. When the accuracy of the pattern shape is not required in the anode 2 (when the accuracy is about 100 μm or more), a desired pattern shape is formed when the anode 2 is formed by a technique such as vapor deposition or sputtering. Alternatively, the anode 2 having a desired pattern may be formed on the element substrate 1 through the mask.

Further, when the anode 2 is formed using a conductive material that can be applied, such as an organic conductive compound, the anode 2 can be formed using a wet film forming method such as a printing method or a coating method.

[Cathode and cathode lead electrode]
The cathode 4 is an electrode film that supplies electrons to the organic light emitting functional layer 3 and can be formed of a conductive material having a small work function (for example, 4 eV or less) that can exhibit an electron injection function. As such a conductive material, a metal, an alloy, an organic or inorganic conductive compound, and a mixture thereof are used.

Specifically, aluminum, 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 ) mixture, The cathode 4 can be formed of a conductive material such as indium, a lithium / aluminum mixture, or a rare earth metal. In addition, when taking out light from the cathode 4 side, the cathode 4 can be formed with the electrode material which has a light transmittance similarly to the said anode 2, for example.

In addition, from the viewpoint of electron injection performance and durability against oxidation, among the various forming materials of the cathode 4, for example, magnesium / silver mixture, magnesium / aluminum mixture, magnesium / indium mixture, aluminum / aluminum oxide (Al ₂ O ₃ ) mixture, lithium / aluminum mixture, etc., that is, a mixture of an electron injecting metal and a second metal, which is a stable metal having a larger work function than that, is preferably used as a material for forming the cathode 4. is there.

The sheet resistance of the cathode 4 is several hundred Ω / sq. The following is preferable. Furthermore, the film thickness of the cathode 4 is appropriately set according to the forming material, and is set, for example, in the range of about 10 nm to 5 μm, preferably about 50 nm to 200 nm.

The cathode 4 having the above configuration is formed by a technique such as vapor deposition or sputtering. Further, when the cathode 4 is formed in a predetermined pattern shape, the same method as the pattern forming method of the anode 2 described above can be used.

Further, since the cathode lead electrode 4a is formed on the element substrate 1 like the anode 2 as will be described later, it is preferable to form the cathode lead electrode 4a with the same material as the anode 2. In particular, the material for forming the cathode lead electrode 4 a is preferably the same as that of the anode 2. In this case, the cathode lead electrode 4 a can be formed simultaneously with the anode 2. Becomes simpler.

In the present embodiment, the example in which the cathode 4 and the cathode through-hole electrode 8 are electrically connected via the cathode lead electrode 4a is shown, but the present invention is not limited to this. For example, the cathode through-hole electrode 8 may be configured to be in direct contact with the cathode 4, and in this case, the cathode lead electrode 4a may not be provided.

[Organic light emitting functional layer]
In FIG. 2, the example of 1 structure of the organic light emission functional layer 3 in the organic EL element 10 of this embodiment is shown. FIG. 2 is a schematic cross-sectional view in the vicinity of the organic light emitting functional layer 3, and the anode 2 and the cathode 4 are also shown for convenience of explanation.

In the example shown in FIG. 2, the organic light emitting functional layer 3 includes a light emitting layer 11, a hole transport layer 12 provided on the anode 2 side of the light emitting layer 11, and an electron transport provided on the cathode 4 side of the light emitting layer 11. Layer 13.

In the organic light emitting functional layer 3 having such a configuration, holes are injected from the anode 2 into the light emitting layer 11 through the hole transport layer 12, and electrons are injected from the cathode 4 into the light emitting layer 11 through the electron transport layer 13. Is done. The injected holes and the injected electrons recombine in the light emitting layer 11 to emit light. The emitted light generated in the light emitting layer 11 is extracted from the anode 2 or the cathode 4 to the outside. Below, each layer which comprises the organic light emission functional layer 3 is demonstrated in detail.

(1) Light-Emitting Layer The light-emitting layer 11 is a layer that generates emitted light by recombination of holes supplied from the anode 2 and electrons supplied from the cathode 4. Such a light emitting layer 11 contains a host material and a guest material having a light emitting property (light emitting dopant compound). In the light emitting layer 11, the light emission efficiency can be increased by causing the guest material to emit light.

Further, the light emitting layer 11 may be composed of a single layer or a structure in which a plurality of light emitting layers having different emission colors (wavelength regions) are laminated. In the latter case, an intermediate layer may be provided between the light emitting layers. Note that the intermediate layer may function as a hole blocking layer or an electron blocking layer.

As the host material, a known host material can be used. In this case, one type of host material may be used alone, or a plurality of types of host materials may be used in combination. When a plurality of types of host materials are used, the movement of charges in the light emitting layer 11 can be adjusted, and the light emission efficiency of the organic EL element 10 can be increased. In addition, by using a plurality of types of light emitting materials (guest materials) described later, it becomes possible to mix a plurality of light emissions having different wavelengths, thereby obtaining an arbitrary light emission color.

As such a host material, a conventionally known low molecular compound may be used, or a high molecular compound having a repeating unit may be used. Further, as the host material, for example, a low molecular compound having a polymerizable group such as a vinyl group or an epoxy group (evaporation polymerizable light emitting host) may be used.

Further, as a known host material, it is a substance responsible for transporting holes and electrons (carriers), has a hole transport function and an electron transport function, has a function of preventing the emission of longer wavelengths, and It is preferable to use a compound having a high glass transition point (Tg). As used herein, “glass transition temperature (Tg)” is a value determined by a method based on JIS-K7121 using a DSC (Differential Scanning Calorimetry) method.

Therefore, as the host material, it is preferable to use a material having a hole transport function and an electron transport function, that is, a carrier transport function as described above. However, generally, since the carrier transport function (carrier mobility) of an organic material depends on the electric field strength, the material having high electric field strength dependency tends to break the balance between injection and transport of holes and electrons. Therefore, as the host material, it is preferable to use a material whose carrier mobility is less dependent on the electric field strength, or a combination of a plurality of materials having the same electric field strength dependency. In this case, the variation in emission color in the organic EL element 10 can be minimized.

As the host material, for example, a material having a basic skeleton such as a carbazole derivative, a triarylamine derivative, an aromatic borane derivative, a nitrogen-containing heterocyclic compound, a thiophene derivative, a furan derivative, an oligoarylene compound, or a carboline derivative Diazacarbazole derivatives (herein, diazacarbazole derivatives are those in which at least one carbon atom of the hydrocarbon ring constituting the carboline ring of the carboline derivative is substituted with a nitrogen atom) and the like can be used .

In the configuration in which a plurality of light emitting layers having different emission colors are provided via an intermediate layer, the intermediate layer also has properties similar to those of the host material. Therefore, by using the material having the above-described physical properties as the material constituting the intermediate layer, the variation in the emission color in the organic EL element 10 can be minimized.

On the other hand, as the guest material, a phosphorescent material (phosphorescent dopant) and a fluorescent material (fluorescent dopant) can be used, and it is particularly preferable to use a phosphorescent material. A plurality of guest materials may be mixed, or a phosphorescent material and a fluorescent material may be mixed in the same light emitting layer 11.

The phosphorescent material is also referred to as a phosphorescent compound or a phosphorescent compound, and can generally be appropriately selected from known materials used for the light emitting layer of the organic EL element. Among them, it is preferable to use a complex compound containing a group 8-10 metal in the periodic table of elements as the phosphorescent material, and further, an iridium compound, an osmium compound, a platinum compound (platinum complex compound), or It is preferable to use a rare earth complex. In particular, it is preferable to use an iridium compound (iridium complex) as the phosphorescent material.

Examples of fluorescent light-emitting materials include coumarin dyes, pyran dyes, cyanine dyes, croconium dyes, squalium dyes, oxobenzanthracene dyes, fluorescein dyes, rhodamine dyes, pyrylium dyes, and perylene dyes. Examples of the material include dyes, stilbene dyes, polythiophene dyes, and rare earth complex phosphors.

Two or more types of guest materials having the above light-emitting properties may be contained in one light-emitting layer 11, and the concentration ratio of the guest materials in the light-emitting layer 11 changes in the thickness direction of the light-emitting layer 11. You may do it.

As described above, the light emitting layer 11 and the intermediate layer formed using the host material and the guest material are, for example, an evaporation method, a spin coating method, a casting method, an LB (Langmuir Blodgett) method, an ink jet method, a printing method, and the like. It can produce by the well-known thin film formation method.

(2) Hole Transport Layer, Electron Transport Layer The hole transport layer 12 and the electron transport layer 13 provided between the anode 2 and the light emitting layer 11 and between the cathode 4 and the light emitting layer 11 are the light emitting layer 11. In consideration of the combination, it can be formed of a conventionally known material.

(3) Other configuration layers In this embodiment, the layer configuration of the organic light emitting functional layer 3 is not limited to the configuration example shown in FIG. 2, and any layer configuration generally known from the past is applied. Can do. The organic light emitting functional layer 3 can be arbitrarily configured as long as it has at least the light emitting layer 11.

For example, a hole injection layer may be provided between the anode 2 and the hole transport layer 12, and an electron injection layer may be provided between the cathode 4 and the electron transport layer 13. Furthermore, you may provide a hole-blocking layer, an electron blocking layer, etc. suitably as needed. Various injection layers are provided for lowering the driving voltage and improving the luminance of light emission. Examples of the material for forming them include “Organic EL elements and their forefront of industrialization” (published by NTS Corporation on November 30, 1998). The materials described in detail in Chapter 2, “Electrode Materials” (pages 123 to 166) in the second volume of “2)” can be used as appropriate. Further, the structure of each electrode film (the anode 2 and the cathode 4) may be a multilayer structure as necessary.

(4) Example of Method for Producing Organic EL Element Here, an example of a technique for producing the element body (element substrate 1, organic light emitting functional layer 3, and various electrode films) of the organic EL element 10 of the present embodiment shown in FIG. Will be explained. A more specific manufacturing method of the organic EL element 10 as a whole will be described in Example 1 described later.

First, a thin film made of a material for an anode is laminated on the element substrate 1 by a method such as vapor deposition or sputtering to form the anode 2. At this time, the film thickness of the anode 2 is set to 1 μm or less, preferably about 10 nm to 200 nm. At this time, in this embodiment, the cathode lead electrode 4 a is formed in a region different from the anode 2 on the element substrate 1. The film configuration (formation material, film thickness, etc.) of the cathode lead electrode 4a is preferably the same as that of the anode 2 and the cathode lead electrode 4a is preferably formed simultaneously with the anode 2.

Next, the organic light emitting functional layer 3 is formed on the anode 2. Specifically, on the anode 2, the organic compound thin films of the hole transport layer 12, the light emitting layer 11, and the electron transport layer 13 are formed in this order to form the organic light emitting functional layer 3.

In addition, as a film-forming method of each organic compound thin film, methods such as a vapor deposition method, a spin coating method, a casting method, an LB method, an ink-jet method, and a printing method can be used as described above. Among these methods, it is particularly preferable to use a vapor deposition method, a spin coating method, an ink jet method, or a printing method. When each organic compound thin film is formed by these methods, for example, there are obtained advantages such that a homogeneous film is easily obtained and pinholes are hardly generated. In the step of forming the organic light emitting functional layer 3, all the organic compound thin films may be formed by the same film forming method, or the film forming method may be changed for each organic compound thin film.

Moreover, when employ | adopting a vapor deposition method as a film-forming method of an organic compound thin film, the vapor deposition conditions are suitably set according to conditions, such as the kind of organic compound to be used. Specifically, the boat heating temperature is about 50 ° C. to 450 ° C., the degree of vacuum is about 10 ⁻⁶ Pa to 10 ⁻² Pa, the deposition rate is about 0.01 nm / second to 50 nm / second, and the substrate temperature is about −50. It is preferable to set the vapor deposition conditions by appropriately selecting from a range of about 150 to 150 ° C. and a film thickness of about 0.1 nm to 5 μm (preferably 5 nm to 200 nm).

After forming the organic light emitting functional layer 3 as described above, a cathode 4 is formed by laminating a thin film made of a cathode material on the organic light emitting functional layer 3 by a method such as vapor deposition or sputtering. The film forming conditions such as the degree of vacuum, the deposition rate, and the substrate temperature at the time of forming the cathode 4 are appropriately selected from the same condition range as the film forming conditions for the organic compound thin film described above. At this time, the thickness of the cathode 4 is set to 1 μm or less, preferably about 50 nm to 200 nm. At this time, the cathode 4 is formed in a pattern shape that is electrically connected to the cathode lead electrode 4a while maintaining an insulating state with respect to the anode 2 via the organic light emitting functional layer 3.

In the present embodiment, the desired organic light emitting functional layer 3 and various electrode films are formed on the element substrate 1 as described above. In the above-described manufacturing method, it is preferable to form the anode 2, the organic light emitting functional layer 3, and the cathode 4 consistently by a single evacuation in the same film forming apparatus, but the present invention is not limited to this. . The organic light emitting functional layer 3 and various electrode films may be formed using different film forming methods by taking out the substrate member for each film forming process. In that case, it is necessary to consider that the work is performed in a dry inert gas atmosphere.

In this embodiment, the example in which the anode 2, the hole transport layer 12, the light emitting layer 11, the electron transport layer 13, and the cathode 4 are formed in this order on the element substrate 1 has been described. It is not limited to. For example, the cathode 4, the electron transport layer 13, the light emitting layer 11, the hole transport layer 12, and the anode 2 may be formed in this order on the element substrate 1 by reversing the stacking order of each film (each layer). . In this case, the cathode 4 is formed of a transparent electrode.

[Sealing substrate]
The sealing substrate 5 is a member that covers the element main body (the element substrate 1, the organic light emitting functional layer 3, and various electrodes) of the organic EL element 10. In the present embodiment, since the anode through-hole electrode 7 and the cathode through-hole electrode 8 are provided through the sealing substrate 5, the sealing substrate 5 is used to ensure the insulation between them. It is made of an insulating material.

Moreover, the sealing base material 5 can be comprised with a plate-shaped (film-shaped) sealing member. In this case, as the sealing substrate 5, a substantially plate-like substrate having a recess formed on one surface, that is, a concave plate-shaped sealing member, a plate-like substrate having a flat surface, That is, a flat sealing member may be used. The plate-like (concave plate or flat plate) sealing substrate 5 is disposed at a position facing the element substrate 1 with the element main body interposed therebetween.

As the sealing substrate 5, for example, a transparent substrate such as a glass plate or a polymer plate can be used. As the glass plate, for example, a substrate formed of a material such as alkali-free glass, soda lime glass, barium / strontium-containing glass, lead glass, aluminosilicate glass, borosilicate glass, barium borosilicate glass, or quartz is used. be able to. Among these, it is particularly preferable to use a glass substrate formed of alkali-free glass or soda-lime glass. Moreover, as a polymer board, the board | substrate formed with materials, such as a polycarbonate, an acryl, a polyethylene terephthalate, a polyether sulfide, a polysulfone, can be used, for example.

Furthermore, in this embodiment, it is preferable that the linear expansion coefficient of the sealing substrate 5 is a value close to that of the element substrate 1. Specifically, difference between the linear expansion coefficient of, is preferably ¹⁰ × 10 ^-6 / ℃ or less, more preferably 5 × ^{10 -6} / ℃ less, 2 × ^{10 -6} / ℃ Most preferably: In addition, when the structure of the element substrate 1 and the sealing base material 5 is a multilayer film structure composed of a plurality of material films, the thickest material film of the plurality of material films constituting each base material is used. The linear expansion coefficients are preferably close to each other. Thus, by making the linear expansion coefficient of the sealing substrate 5 substantially the same value as that of the element substrate 1, the organic EL element 10 after being bonded together, the sealing substrate 5 is peeled off, or the like. Can be suppressed.

In terms of reducing the thickness of the organic EL element 10, it is preferable to use a polymer plate as the sealing substrate 5. In the case where a polymer plate is used as the sealing substrate 5, a barrier film made of an inorganic material, an organic material is used on the surface of the polymer plate in order to suppress, for example, water vapor and oxygen from passing into the organic EL element 10. It is preferable to provide a barrier film made of a material or a hybrid film in which these barrier films are stacked. Such a barrier film has an oxygen permeability of 10 ⁻³ cm ³ / (m ² · 24 h · atm) or less and a water vapor permeability of 10 ⁻³ g / (m ² · 24 h) or less. It is preferable to use the film | membrane which is. Further, the water vapor permeability of the barrier film is 10 ⁻⁵ g / (m ² · 24 h) or less, or the oxygen permeability of the barrier film is 10 ⁻⁵ cm ³ / (m ² · 24 h · atm). The following is preferable.

In addition, in this embodiment, as shown in FIG. 1, it is preferable to use a flat sealing member as the sealing substrate 5, and to stick the whole surface to the element substrate 1 with an adhesive. By adopting such a sealing form, a thin and lightweight organic EL element 10 (planar light emitter) can be provided. Moreover, when a flexible base material is used for the element substrate 1 and the sealing base material 5, a flexible organic EL element 10 (planar light emitter) can also be provided.

However, when the desiccant is not encapsulated in such a sealing form, the storage characteristics are affected by the distance from the side end of the light emitting region of the organic light emitting functional layer 3 to the end of the sealing side. FIG. 3 shows the relationship between the distance (sealing margin) from the side end of the light emitting region to the sealing side end of the organic light emitting functional layer 3 and the area where dark spots are generated in the organic EL element 10. In the characteristics shown in FIG. 3, the horizontal axis is the margin for sealing, and the vertical axis is the dark spot generation area. As is clear from FIG. 3, when the sealing margin is small, the dark spot generation area is large (the storage characteristic is deteriorated), but when the sealing margin is large, the dark spot generation area is small, and finally, It turns out that it is saturated. That is, in order to ensure good storage characteristics, a certain amount of sealing width, that is, a non-light emitting region is required.

Further, when the sealing substrate 5 is constituted by a concave plate-shaped sealing member (when can sealing), the concave portion is formed by a process such as a sandblasting process or a chemical etching process. In addition, when comprising the sealing base material 5 with a concave-plate-shaped sealing member, the sealing base material 5 and the element main-body part (the element substrate 1, the organic light emission functional layer 3, and various electrodes) of the organic EL element 10 are included. The gap is preferably filled with, for example, an inert gas such as nitrogen or argon, or an inert liquid such as fluorinated hydrocarbon or silicon oil. Further, the gap between the sealing substrate 5 and the element main body of the organic EL element 10 may be in a vacuum state, or a hygroscopic compound may be sealed in the gap.

Examples of the hygroscopic compound include metal oxides (for example, sodium oxide, potassium oxide, calcium oxide, barium oxide, magnesium oxide, aluminum oxide, etc.), 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 chlorate, magnesium perchlorate, etc.) can be used. Among these compounds, when a sulfate, a metal halide, or perchloric acid is used as the hygroscopic compound, it is preferable to use an anhydrous salt.

Further, as the sealing substrate 5, a sealing film may be used. When the film sealing method is used, the organic light emitting functional layer 3 is completely covered with the sealing film. In the present embodiment, since the anode through-hole electrode 7 and the cathode through-hole electrode 8 are provided as power supply terminals, an opening is provided in each through-hole electrode formation region of the sealing film, and the opening is provided in the opening. A sealing film is formed so that the anode 2 and the cathode 4 are exposed.

Such a sealing film can be composed of a film made of an inorganic material or an organic material. Note that the sealing film is formed of a material having a function of suppressing intrusion of a substance such as moisture or oxygen, which causes deterioration of the organic light emitting functional layer 3. Examples of the material having such properties include inorganic materials such as silicon oxide, silicon dioxide, and silicon nitride. Furthermore, in order to improve the brittleness of the sealing film, the structure of the sealing film may be a multilayer structure in which a film made of these inorganic materials and a film made of an organic material are laminated.

Any method can be used as the method for forming the sealing film described above. For example, a vacuum deposition method, a sputtering method, a reactive sputtering method, a molecular beam epitaxy method, a cluster ion beam method, an ion plating method, Techniques such as plasma polymerization, atmospheric pressure plasma polymerization, plasma CVD, laser CVD, thermal CVD, and coating can be used.

[Sealant]
The sealing material 6 is formed of, for example, a liquid adhesive, a sheet-like adhesive, a thermoplastic resin adhesive, or the like when the sealing substrate 5 is a flat sealing member (in the case of solid adhesive sealing). can do.

Examples of the liquid adhesive include photo-curing or thermosetting sealing agents having reactive vinyl groups such as acrylic acid oligomers and methacrylic acid oligomers, and moisture-curing adhesives such as 2-cyanoacrylate, Epoxy-based thermosetting and chemical curing (two-component mixed) adhesives, cationic curing ultraviolet curing epoxy resin adhesives, and the like can be used.

In addition, it is preferable to add a filler to the liquid adhesive as necessary. The amount of filler added is preferably 5 to 70% by volume in consideration of adhesive strength. In addition, the size of the filler to be added is preferably 1 μm to 100 μm in consideration of the adhesive strength, the thickness of the adhesive after bonding and bonding, and the like. Any filler can be used, for example, soda glass, alkali-free glass, silica, or the like. As the filler, for example, metal oxides such as titanium dioxide, antimony oxide, titania, alumina, zirconia, and tungsten oxide can be used.

When the sealing substrate 5 and the element main body of the organic EL element 10 are bonded using a liquid adhesive, the bonding stability, the prevention of air bubbles from being mixed into the bonding part, the flexible sealing group In consideration of maintaining the flatness of the material, it is preferable to perform the bonding process under reduced pressure conditions of 10 Pa to 1 × 10 ⁻⁵ Pa.

The sheet-like adhesive is an adhesive formed into a sheet shape that exhibits non-flowability at room temperature (about 25 ° C.) and exhibits fluidity in the range of 50 ° C. to 100 ° C. when heated. Examples of the sheet-like adhesive include a photo-curing resin mainly composed of a compound having an ethylenic double bond at the molecular end or side chain and a photopolymerization initiator. When using this sheet-like adhesive, for example, it is preferable to use the sheet-like adhesive in a state in which the sheet-like adhesive is bonded to the sealing substrate 5 in advance and at room temperature (about 25 ° C.) or lower.

As the thermoplastic resin, it is preferable to use a thermoplastic resin having a melt flow rate of 5 to 20 [g / 10 min] according to JIS-K-7210, and a melt flow rate of 6 to 15 [g / 10 min]. It is preferable to use a thermoplastic resin. This is because if a thermoplastic resin having a melt flow rate of 5 [g / 10 min] or less is used, it is difficult to completely fill a gap formed by the step of the extraction electrode portion (extraction electrode portion) of each electrode film with the resin. It is. The reason why the range of the melt flow rate is preferable is that when a resin having a melt flow rate of 20 [g / 10 min] or more is used, characteristics such as tensile strength, stress cracking resistance, and workability are deteriorated. Because.

When a thermoplastic resin is used, it is preferable to use the thermoplastic resin molded into a film shape and the molded film resin bonded to the sealing substrate 5. As the bonding method, various generally known methods such as a wet laminating method, a dry laminating method, a hot melt laminating method, an extrusion laminating method, and a thermal laminating method can be used.

As the thermoplastic resin, any resin can be used as long as the melt flow rate satisfies the above numerical range. For example, it is described in “New development of functional packaging material” (Toray Research Center, Inc.). Low density polyethylene (LDPE), HDPE, linear low density polyethylene (LLDPE), medium density polyethylene, unstretched polypropylene (CPP), OPP, ONy, PET, cellophane, polyvinyl alcohol (PVA), Use of stretched vinylon (OV), ethylene-vinyl acetate copolymer (EVOH), ethylene-propylene copolymer, ethylene-acrylic acid copolymer, ethylene-methacrylic acid copolymer, vinylidene chloride (PVDC), etc. it can. Among these thermoplastic resins, it is particularly preferable to use LDPE or LLDPE. Further, LDPE or LLDPE produced using a metallocene catalyst may be used as the thermoplastic resin. Further, a thermoplastic resin obtained by mixing LDPE or LLDPE and an HDPE film may be used.

Moreover, when the sealing base material 5 is a concave-plate-shaped sealing member (in the case of can sealing), as the sealing material 6, the photocuring which has the reactive vinyl group of an acrylic acid type oligomer or a methacrylic acid type oligomer is carried out. A mold or thermosetting adhesive, a moisture curable adhesive such as 2-cyanoacrylate, and the like can be used. Further, in this case, as the sealing material 6, an epoxy-based thermosetting type or chemical curing type (two-component mixed) adhesive can be used. Further, hot-melt type polyamide, polyester, polyolefin or the like may be used as the sealing material 6. In addition, a cationic curing type ultraviolet curing epoxy resin adhesive may be used as the sealing material 6.

In addition, when the sealing base material 5 is a concave plate-shaped sealing member, among the various adhesives that can be used as the sealing material 6, in order to prevent deterioration due to heat treatment of the organic EL element 10, the temperature is changed from room temperature to 80 ° C. It is preferable to use an adhesive that cures within a temperature range up to. Further, a desiccant may be dispersed in the various adhesives described above. In addition, the application | coating process of the adhesive agent to a sealing part may be implemented using a dispenser, and may be implemented using screen printing.

[Through hole of through hole electrode and sealing substrate]
In the organic EL element 10 of the present embodiment, when the element substrate 1 and the sealing base material 5 are disposed to face each other, the lead electrode part of the anode 2 and the inside of the sealing base material 5 facing the cathode lead electrode 4a are arranged. Through

holes

5a and 5b for forming the anode through-hole electrode 7 and the cathode through-hole electrode 8 are formed at positions.

The opening shape of each through hole can be any shape, for example, a circular shape. In this case, the through-hole electrode can be easily formed. Moreover, it is preferable to increase the opening area (diameter) of each through-hole from the surface on the sealing material 6 side toward the surface opposite to the sealing material 6 side. That is, it is preferable that the side wall surface of the sealing substrate 5 that defines each through hole is tapered.

The opening area of each through hole is preferably smaller from the viewpoint of sealing performance, and specifically, it is preferably 1 mm ² or less. From this viewpoint, the opening area of each through hole is more preferably 0.8 mm ² or less, and particularly preferably 0.5 mm ² or less. In addition, when the side wall surface of the sealing base material 5 that defines each through hole is tapered, the opening area of the surface opposite to the sealing material 6 side of each through hole (the one with the larger opening diameter) The opening area) preferably satisfies this area range.

In addition, the opening area of each through hole is preferably larger and is preferably 0.3 mm ² or more from the viewpoint of improving the conductivity and suppressing the increase in driving voltage. From this viewpoint, the opening area of each through hole is more preferably 0.7 mm ² or more, and particularly preferably 0.9 mm ² or more. In addition, when the side wall surface of the sealing base material 5 that defines each through hole is tapered, the opening area of the surface on the sealing material 6 side of each through hole (the opening area with the smaller opening diameter) is It is preferable to satisfy this area range.

As a method for forming the through hole, a known method can be used. When the sealing substrate 5 is made of glass, for example, a technique such as sand blasting or processing using a micro drill can be used. In the case of using sandblasting, by using a blasting material of about 10 μm to 100 μm, it is possible to easily form a through hole having a size within the above-mentioned preferred range. When a micro drill is used, it is preferable to use a diamond drill or the like as the micro drill. Moreover, when the sealing base material 5 is formed with resin, for example, a minute through hole can be formed by using a technique such as drilling or laser processing.

And in this embodiment, each through-hole of the sealing base material 5 is filled with the formation material of a through-hole electrode, and after that, it shape | molds by machining and forms a through-hole electrode. Since the through-hole electrode needs to act not only as a power supply terminal (external lead-out terminal) to the anode 2 and the cathode 4 as described above, but also as a sealing member, the filler filling the through hole As the (forming material for the through-hole electrode), a filler having conductivity and sealing properties is used. Note that the “filler having sealing properties” referred to here has an oxygen permeability of 10 ⁻³ cm ³ / (m ² · 24 h · atm) or less and a water vapor permeability of 10 ⁻³ g / It refers to a filler that is (m ² · 24h) or less.

As the filler, any material can be used as long as it satisfies the above conditions. For example, a low melting point alloy such as solder can be used as the filler. In this case, the through-hole electrode can be formed by melting the low melting point alloy and filling the through hole, and then forming the filler by, for example, machining.

Also, a metal paste such as a silver paste may be used as the filler. Furthermore, metal nanoparticles (a paste-like filler in which metal nanoparticles are contained in a solvent or the like) may be used as the filler. When these fillers are used, a through-hole electrode can be formed by filling a through-hole with a paste-like filler and firing, and then molding the fired filler, for example, by machining. .

In addition, when the element substrate 1 and the sealing substrate 5 are bonded together, it is necessary to bring the through-hole electrode into contact with the corresponding electrode film (anode 2 or cathode 4) to be electrically connected. The through-hole electrode is formed so that the hole electrode protrudes outward from the surface of the sealing substrate 5 on the sealing material 6 side (becomes convex). As for the shape of the through-hole electrode, the shape of the tip portion of the through-hole electrode on the sealing material 6 side is more from the viewpoint of penetrability with respect to the sealing material 6 (sealing adhesive) and improvement of contact with the electrode film. A sharp shape is preferred. For example, the shape of the tip portion of the through-hole electrode may be a truncated cone shape or a conical shape as shown in FIG. Note that the through-hole electrode may be cylindrical, as will be described in the examples described later.

[Light extraction member]
Although not shown in FIG. 1, the organic EL element 10 of the present embodiment transmits incident light to the light extraction surface (surface opposite to the sealing base 5 of the element substrate 1) and emits it. You may provide the light extraction member which has the function to do. The light extraction member is composed of a sheet-like, film-like, plate-like, or film-like optical member. Here, the arrangement state and configuration of the light extraction member will be briefly described.

The light extraction member is configured by using, for example, a light diffusion sheet or a light collecting sheet. As the light diffusion sheet, a conventional general light diffusion sheet can be used, and for example, a sheet member having irregularities formed on the surface can be used. In addition, as the condensing sheet, a general condensing sheet called a prism sheet can be used. For example, a sheet practically used for an LED (Light Emitting Diode) backlight of a liquid crystal display device can be used. it can. Specifically, as the condensing sheet, for example, a sheet in which a plurality of stripes having an apex angle of 90 degrees and a triangular cross-sectional shape are formed on a sheet base material at a pitch of 50 μm can be used.

In addition, various shapes can be applied as the uneven shape on the surface of the light collecting sheet, and can be appropriately set in consideration of, for example, the use and the required light collecting property. For example, the uneven shape on the surface of the light collecting sheet may be a shape in which the apex angle of the stripe is rounded (the cross-sectional shape is substantially triangular), or a shape in which the pitch of the stripe is randomly changed. .

The light extraction member having the above-described configuration is attached to the element substrate 1 via an adhesive (not shown). In addition, it is preferable that this adhesive agent has high light transmittance. Further, as this adhesive, an adhesive having a refractive index comparable to that of the element substrate 1 may be used.

<2. Structure of planar light emitter>
Next, a planar light emitter produced by arranging (tiling) a plurality of organic EL elements 10 will be described.

[Configuration of planar light emitter]
FIG. 4 shows a schematic cross-sectional view of a planar light emitter according to an embodiment of the present invention. FIG. 4 shows a configuration example in which two organic EL elements 10 are arranged for the sake of simplification, but the present invention is not limited to this, and the organic EL element 10 constituting a planar light emitter is shown. The number of sheets and the arrangement form are appropriately set according to, for example, the application.

The planar light emitter 20 includes two organic EL elements 10, a support substrate 21 (support member), and an adhesive member 22 for fixing each organic EL element 10 on the support substrate 21.

In the planar light-emitting body 20, the surface of each organic EL element 10 on the sealing substrate 5 side is fixed on the large support substrate 21 by the adhesive member 22. At this time, in the example shown in FIG. 4, the through-hole electrodes (the anode through-hole electrode 7 and the cathode through-hole electrode 8) are exposed on the surface of each organic EL element 10 on the sealing substrate 5 side. The adhesive member 22 is provided in a region where there is not.

Further, in the planar light-emitting body 20, the two organic EL elements 10 are arranged on the support substrate 21 so that the opposing side surfaces of the element substrate 1 are in contact with each other at the joint portion between the two organic EL elements 10. To do. At this time, the two organic EL elements 10 are arranged so that the light extraction surfaces (surfaces opposite to the sealing substrate 5 of the element substrate 1) are flush with each other. The EL elements 10 are arranged on the support substrate 21. Hereinafter, the configuration of each part of the planar light emitter 20 will be described more specifically.

[Support substrate]
The support substrate 21 can be composed of any plate-like member as long as it can hold the state of the two organic EL elements 10 mounted thereon via the adhesive member 22. In this embodiment, since light is not extracted from the support substrate 21 side, the support substrate 21 does not need to be formed of a light-transmitting material and can be formed of an arbitrary material.

In addition, when it is set as the structure which bends the planar light-emitting body 20 flexibly, the support substrate 21 is comprised with the flexible substrate which has a flexibility. As such a flexible substrate, for example, a resin film or a glass substrate having a thickness of about 0.01 mm to 0.50 mm can be used.

[Adhesive member]
In this embodiment, in various industrial fields, it is applied onto the support substrate 21 or the sealing substrate 5 among the adhesive members used in designations such as pressure-sensitive adhesives, adhesives, or pressure-sensitive adhesives, adhesives, After the organic EL element 10 and the support substrate 21 are bonded together, a curable adhesive member 22 that forms a high molecular weight body or a crosslinked structure by various chemical reactions is used. That is, the bonding member 22 is formed of a material that cures the bonded portion by irradiating light such as ultraviolet rays, applying heat, or applying pressure.

Examples of the adhesive member 22 having the above-described physical properties include urethane type, epoxy type, fluorine-containing type, aqueous polymer-isocyanate type, acrylic type curable adhesives, moisture-cured urethane adhesives, polyethers, and the like. Examples include anaerobic adhesives such as methacrylate type, ester type methacrylate type, and oxidized polyether methacrylate, cyanoacrylate type instant adhesives, and acrylate and peroxide type two-pack type instant adhesives.

Also, as a method for forming the adhesive member 22, any method can be used, and in particular, a method capable of supplying an uncured adhesive can be used. Examples of such a technique include techniques such as a gravure coater, a micro gravure coater, a comma coater, a bar coater, spray coating, and an ink jet method. In addition, a method suitable for the adhesive to be used is used as a method for curing the uncured adhesive member 22.

In the case of using a photo-curing type adhesive, in order to prevent the deterioration of the organic light emitting functional layer 3 due to light irradiation, the light emitting region of the organic EL element 10 is covered with a mask, and then the light irradiation is performed. Can be cured. Further, when a thermosetting adhesive is used, it is preferable to cure the adhesive by low-temperature heating to such an extent that deterioration of the organic light emitting functional layer 3 due to heating can be prevented.

Furthermore, as the adhesive member 22, an adhesive in which a predetermined material is added to the above-described various curable adhesives in a range that does not impair the adhesiveness may be used. As such an adhesive, for example, an adhesive in which an inorganic material such as glass or silica is dispersed may be used, or an adhesive to which a resin, a pressure-sensitive adhesive, or another adhesive is added (mixed). May be used.

In addition, as resin added to an adhesive agent, transparent resins, such as PET (polyethylene terephthalate), TAC (triacetylcellulose), PC (polycarbonate), PMMA (polymethylmethacrylate) etc., are used, for example. Examples of the pressure-sensitive adhesive include an anaerobic pressure-sensitive adhesive such as urethane-based, epoxy-based, aqueous polymer-isocyanate-based, and acrylic-based pressure-sensitive adhesives, polyether methacrylate-type, ester-based methacrylate-type, and oxidized polyether methacrylate. Further, curable adhesives such as urethane, epoxy, aqueous polymer-isocyanate, and acrylic can be used. Furthermore, various UV curable resins, thermosetting resins, and the like can be used as additive materials. Further, a light scattering or light reflecting material may be added (dispersed) to the adhesive member 22.

<3. Various modifications>
Below, the various modifications of the organic EL element 10 and the planar light-emitting body 20 of the said embodiment are demonstrated.

[Modification 1]
In the above embodiment, the configuration of the solid adhesion sealing type organic EL element 10 has been described, but the present invention is not limited thereto. The above technique of the present invention can also be applied to an organic EL element of a type that seals in a state where a gap is provided between an element substrate and a sealing substrate, such as a can sealing type. In Modification 1, a can-sealed organic EL element will be described as a first example of such an organic EL element.

FIG. 5 shows a schematic cross-sectional view of the organic EL element of Modification 1. In addition, in the organic EL element 30 shown in FIG. 5, the same code | symbol is attached | subjected and shown to the structure same as the organic EL element 10 of the said embodiment shown in FIG.

The organic EL element 30 includes an element substrate 1, an anode 2, an organic light emitting functional layer 3, a cathode 4, a cathode lead electrode 4 a, a sealing substrate 31, a sealing material 32, and an anode through-hole electrode 7. And a through-hole electrode 8 for cathode.

As is clear from comparison between FIG. 5 and FIG. 1, in the organic EL element 30 of this example, the configuration other than the sealing base material 31 and the sealing material 32 is the same as the corresponding configuration of the organic EL element 10 of the above embodiment. It is the same. Therefore, only the configuration of the sealing base material 31 and the sealing material 32 will be described here.

The sealing substrate 31 is formed of a concave plate-shaped sealing member having a concave portion 31c formed on one surface. In addition, the sealing base material 31 can be formed with the material similar to the sealing base material 5 of the organic EL element 10 of the said embodiment. As described above, the recess 31c of the sealing substrate 31 is formed by a process such as a sandblasting process or a chemical etching process.

Further, in this example, in the recess 31c of the sealing substrate 31, tapered through holes (31a, 31b) are formed at positions corresponding to the region of the extraction electrode portion of each electrode film, as in the above embodiment. A frustum-shaped through-hole electrode (7, 8) is formed in the through-hole. At this time, the through-hole electrode is formed so as to protrude outward from the concave portion 31 c of the sealing substrate 31.

The sealing material 32 is provided on the upper surface of the convex outer peripheral end portion 31 d that defines the concave portion 31 c of the sealing base material 31. As the sealing material 32, similar to the sealing material 6 of the above embodiment, a photocurable or thermosetting adhesive having a reactive vinyl group of an acrylic acid oligomer or a methacrylic acid oligomer, 2-cyanoacrylic acid. A moisture curable adhesive such as an ester can be used.

And in this example, the inside is sealed by bonding the sealing substrate 31 and the element substrate 1 so that the recess 31c and the surface of the element substrate 1 on the organic light emitting functional layer 3 side face each other. The organic EL element 30 is produced. In this case, as shown in FIG. 5, a gap 33 is defined between the sealing substrate 31 and the element body (element substrate 1, organic light emitting functional layer 3, and various electrode films) of the organic EL element 30. The

In the organic EL element 30 of this example, it is preferable to fill the gap 33 with an inert gas such as nitrogen or argon, or an inert liquid such as fluorinated hydrocarbon or silicon oil, as described above. . In this example, the gap 33 may be in a vacuum state, or a hygroscopic compound may be enclosed in the gap 33.

Also in this example, as in the above-described embodiment, the entire element substrate 1 is covered with the sealing substrate 31, and a through-hole electrode is provided for each electrode film. Therefore, also in this example, the same effect as the above embodiment can be obtained.

[Modification 2]
In Modification 2, a second example of an organic EL element that is sealed in a state where a gap is provided between the element substrate and the sealing substrate will be described. FIG. 6 shows a schematic cross-sectional view of the organic EL element of Modification 2. In addition, in the organic EL element 40 shown in FIG. 6, the same code | symbol is attached | subjected and shown to the structure same as the organic EL element 10 of the said embodiment shown in FIG.

The organic EL element 40 includes an element substrate 1, an anode 2, an organic light emitting functional layer 3, a cathode 4, a cathode lead electrode 4 a, a sealing substrate 5, a sealing material 41, and an anode through-hole electrode 7. And a through-hole electrode 8 for cathode.

As apparent from the comparison between FIG. 6 and FIG. 1, in the organic EL element 40 of this example, the configuration other than the sealing material 41 is the same as the corresponding configuration of the organic EL element 10 of the above embodiment. Therefore, only the configuration of the sealing material 41 will be described here.

In this example, a flat plate-shaped sealing member is used as the sealing substrate 5 as in the above embodiment. Then, when the sealing substrate 5 and the element substrate 1 are bonded together, the sealing material 41 is provided only in the vicinity of the outer peripheral end portion of the sealing substrate 5. At this time, the sealing material 41 is provided in a region from a predetermined position on the outer peripheral end side of the sealing substrate 5 to the outer peripheral end from the through-hole electrode. Moreover, the sealing material 41 can be formed with the material similar to the sealing material 6 of the said embodiment.

When the sealing base material 5 and the element substrate 1 are bonded to each other using the sealing material 41 having the above-described configuration, the element main body portion (the element substrate 1, the organic substrate) of the organic EL element 40 is the same as the first modification. A gap 42 is defined between the light emitting functional layer 3 and various electrode films) and the sealing substrate 5.

In this example as well, as in the above embodiment, the entire element substrate 1 is covered with the sealing substrate 5 and a through-hole electrode is provided for each electrode film. Therefore, also in this example, the same effect as the above embodiment can be obtained.

[Modification 3]
In Modification 3, a third example of an organic EL element that is sealed in a state where a gap is provided between the element substrate and the sealing substrate will be described. FIG. 7 shows a schematic cross-sectional view of an organic EL element of Modification 3. In addition, in the organic EL element 50 shown in FIG. 7, the same code | symbol is attached | subjected and shown to the same structure as the organic EL element 40 of the modification 2 shown in FIG.

The organic EL element 50 includes an element substrate 1, an anode 2, an organic light emitting functional layer 3, a cathode 4, a cathode lead electrode 4 a, a sealing substrate 5, a sealing material 51, and an anode through-hole electrode 7. And a through-hole electrode 8 for cathode.

As is clear from a comparison between FIG. 7 and FIG. 6, the configuration of the organic EL element 50 in this example is a configuration in which the formation region of the seal material 51 is changed from that of the second modification. Other configurations are the same as the corresponding configurations of the organic EL element 40 of the second modification. Therefore, only the configuration of the sealing material 51 will be described here.

In this example, a flat sealing member is used as the sealing substrate 5 as in the above embodiment. And in this example, the sealing material 51 is provided in the area | region from the predetermined position of the center side of the sealing base material 5 to an outer periphery end from a through-hole electrode. In this case, the sealing material 51 is formed so as to cover the side wall of the through-hole electrode protruding from the surface of the sealing substrate 5 on the sealing material 51 side. In addition, the sealing material 51 can be formed with the material similar to the sealing material 6 of the said embodiment.

Even when the sealing base material 5 and the element substrate 1 are bonded together using the sealing material 51 having the above-described configuration, the element main body (the element substrate 1 and the organic substrate) of the organic EL element 50 are formed in the same manner as in the second modification. A gap 52 is defined between the light emitting functional layer 3 and various electrode films) and the sealing substrate 5.

[Modification 4]
In the above embodiment, an example in which one through-hole electrode is provided in each of the anode 2 and the cathode 4 (each electrode film) is described. However, the present invention is not limited to this, and a plurality of through-hole electrodes are provided in each electrode film. May be provided.

[Modification 5]
In the above embodiment, the example in which the above-described technique of the present invention is applied to the bottom emission type organic EL element 10 that extracts light from the element substrate 1 side has been described, but the present invention is not limited to this. The above technique of the present invention can also be applied to a top emission type organic EL element that extracts light from the sealing substrate side.

In this case, it is necessary to form the cathode and the sealing substrate with a transparent material. In this case, from the viewpoint of ease of production of the through-hole electrode, it is preferable to provide the through-hole electrode on the sealing substrate. However, in order to enlarge the light emitting region, the through-hole electrode may be provided on the element substrate. Good.

[Modification 6]
Although the planar light-emitting body 20 of the said embodiment demonstrated the structural example which supports the some organic EL element 10 using the large sized support substrate 21, this invention is not limited to this. For example, the side walls of the opposing element substrates may be joined with an adhesive between two adjacent organic EL elements. In this case, the adhesive can be used as a support member for the organic EL element, and the large support substrate 21 need not be provided separately.

<4. Various Examples and Evaluation Results>
Next, the structure of various examples of the organic EL element of the present invention actually produced, the evaluation test performed on the sample of the organic EL element produced in each example, and the results will be described.

[Configuration of element body]
First, before describing the specific configuration and manufacturing method of various examples, the configuration of the element body used in the organic EL elements of the various examples will be described. FIG. 8 shows a schematic cross-sectional view of the element body used in the organic EL elements of various examples.

The element body portion 60 of the organic EL element of various embodiments described below includes an element substrate 61, an anode 62, a hole injection layer 63, a hole transport layer 64, a yellow light emitting layer 65, and a blue light emitting layer. 66, a hole blocking layer 67, an electron transport layer 68, an electron injection layer 69, and a cathode 70. In this example, on the element substrate 61, the anode 62, the hole injection layer 63, the hole transport layer 64, the yellow light emitting layer 65, the blue light emitting layer 66, the hole blocking layer 67, the electron transport layer 68, the electron injection. The layer 69 and the cathode 70 are laminated in this order.

That is, in this example, the hole emitting layer 63, the hole transporting layer 64, the yellow light emitting layer 65, the blue light emitting layer 66, the hole blocking layer 67, the electron transporting layer 68, and the electron injecting layer 69, and the organic light emitting functional layer 71. Configure. In addition, since the organic EL elements of the following various examples are bottom emission type elements that extract light emitted from the light emitting layer (the yellow light emitting layer 65 and the blue light emitting layer 66) from the anode 62 side, the anode 62 is transparent. The cathode 70 is composed of a reflective electrode (metal film).

[Example 1]
Here, the manufacturing method of the organic EL element of Example 1 and the configuration (for example, material, dimensions, etc.) of each part will be specifically described with reference to the drawings.

(1) Manufacturing Method of Element Main Body First, a manufacturing method of the element main body 60 will be described with reference to FIGS. 9A and 9B to 13. 9A and 9B to FIGS. 12A and 12B are diagrams showing a schematic configuration of the substrate member obtained by each processing step, and FIGS. 9A, 10A, 11A and 12A are plan views of the base member. 9B, 10B, 11B, and 12B are cross-sectional views taken along line AA in FIGS. 9A, 10A, 11A, and 12A, respectively. FIG. 13 is a diagram showing a light emitting region.

First, a transparent glass substrate (Corning EAGLE XG: non-alkali glass) having a thickness of 0.7 mm and an area of 60 mm × 60 mm (a square shape) was prepared as the element substrate 61 (state of FIGS. 9A and 9B). .

Next, an ITO film (transparent conductive material) having a film thickness of 150 nm was formed on one surface 61a of the element substrate 61 (upper surface in FIG. 10B). Next, a patterning process was performed on the ITO film to form an anode 62 having a predetermined shape and a cathode lead electrode 70a (states of FIGS. 10A and 10B).

At this time, as shown in FIG. 10A, the cathode lead-out electrode 70a was formed of a striped ITO film extending in the vicinity of one side of the element substrate 61 along the side. On the other hand, the anode 62 was formed over substantially the entire region other than the formation region of the cathode lead electrode 70a on one surface 61a of the element substrate 61, and the anode 62 having a substantially rectangular surface was formed. At this time, in order to ensure insulation between the anode 62 and the cathode lead-out electrode 70a, both were formed separated by a predetermined distance.

Next, the element substrate 61 on which the anode 62 and the cathode lead electrode 70a were formed was ultrasonically cleaned with isopropyl alcohol. Thereafter, the cleaned element substrate 61 was dried with dry nitrogen gas, and further, UV ozone cleaning was performed on the dried element substrate 61 for 5 minutes.

Next, the element substrate 61 on which the anode 62 and the cathode lead-out electrode 70a were formed was fixed to a substrate holder of a vacuum evaporation apparatus, and a vapor deposition mask was disposed opposite to the formation surface side of the anode 62 of the element substrate 61. Further, each of the various vapor deposition boats in the vacuum vapor deposition apparatus was filled with the material for forming the various layers constituting the organic light emitting functional layer 71 and the cathode 70 in an optimum amount for forming each layer. In addition, the boat for vapor deposition used what was produced with the resistance heating material of molybdenum or tungsten.

Next, after the pressure in the vapor deposition chamber of the vacuum vapor deposition apparatus is reduced to a vacuum degree of 4 × 10 ⁻⁴ Pa, the vapor deposition boat containing the respective materials is sequentially energized and heated. A light emitting functional layer 71 was formed.

First, as a material for forming the hole injection layer 63, CuPc (copper phthalocyanine) represented by the following structural formula (1) is used, and this hole injection material is deposited on the anode 62 at a deposition rate of 0.1 nm / second. The hole injection layer 63 having a thickness of 15 nm was formed by vapor deposition.

Next, a triarylamine derivative represented by the following structural formula (2) (α-NPD) is used as a material for forming the hole transport layer 64, and this hole transport material is deposited on the hole injection layer 63. Vapor deposition was performed at a rate of 0.1 nm / second to form a hole transport layer 64 having a thickness of 25 nm.

Next, a carbazole derivative represented by the following structural formula (3) (HA) is used as the host material, and an iridium compound represented by the following structural formula (4) (DB) is used as the green guest material. As the red guest material, an iridium compound represented by the following structural formula (5) (DC) is used, and these compounds are deposited on the hole transport layer 64 at a total deposition rate of 0.1 nm / second. The yellow light emitting layer 65 having a film thickness of 10 nm was formed by co-evaporation. In the yellow light emitting layer 65, the proportion of the green guest material (DB) was 10 mass%, and the proportion of the red guest material (DC) was 2 mass%.

Next, the carbazole derivative represented by the above structural formula (3) (HA) is used as the host material, and the iridium compound represented by the following structural formula (6) (DA) is used as the blue guest material. These compounds were co-evaporated on the yellow light-emitting layer 65 at a total deposition rate (sum of the deposition rates of the respective materials) of 0.1 nm / second to form a blue light-emitting layer 66 having a thickness of 15 nm. In addition, the ratio of the blue guest material in the blue light emitting layer 66 was 10 mass%.

Next, an aluminum quinolinol complex represented by the following structural formula (7) (BAlq) is used as a material for forming the hole blocking layer 67, and this hole blocking material is deposited on the blue light emitting layer 66 at a deposition rate of 0.1 nm. The hole blocking layer 67 having a film thickness of 15 nm was formed by vapor deposition at a rate of / sec.

Next, an aluminum quinolinol complex represented by the following structural formula (8) (Alq3) is used as a material for forming the electron transport layer 68, and this electron transport material is deposited on the hole blocking layer 67 at a deposition rate of 0.1 nm / Evaporation was performed in seconds to form an electron transport layer 68 having a thickness of 30 nm.

Then, lithium fluoride (LiF) is used as a material for forming the electron injection layer 69, and this electron injection material is deposited on the electron transport layer 68 at a deposition rate of 0.1 nm / second, thereby injecting an electron with a thickness of 1 nm. Layer 69 was formed.

In this example, an organic light emitting functional layer 71 was formed in this way (the state shown in FIGS. 11A and 11B). At this time, as shown in FIG. 11A, the organic light emitting functional layer 71 was formed in a region other than the lead electrode portion of the anode 62 (a region where the anode through-hole electrode was brought into contact). At this time, the organic light emitting functional layer 71 was formed so that the organic light emitting functional layer 71 did not cover the cathode extraction electrode 70a.

Next, aluminum (Al) was used as a material for forming the cathode 70, and this cathode material was deposited on the organic light emitting functional layer 71 (electron injection layer 69) to form the cathode 70 with a film thickness of 110 nm (FIGS. 12A and 12B). 12B state). At this time, as shown in FIG. 12A, the cathode 70 was formed so as to cover not only the organic light emitting functional layer 71 but also a part of the cathode lead electrode 70a. As a result, the cathode 70 is electrically connected to the cathode lead electrode 70a.

In this example, the element body 60 of the organic EL element was produced as described above. In the element main body 60 manufactured as described above, as shown in FIG. 13, a region where the anode 62 and the cathode 70 face each other with the organic light emitting functional layer 71 interposed therebetween (hatched region in FIG. 13). ) Is the light emitting area SA.

(2) Manufacturing method and bonding method of sealing substrate Next, a manufacturing method of the sealing substrate on which the through-hole electrode and the sealing material are formed is specifically described with reference to FIGS. 14A and 14B to FIG. explain. 14A and 14B to 16A and 16B are diagrams showing a schematic configuration of the substrate member obtained by each processing step, and FIGS. 14A, 15A and 16A are plan views of the base member, respectively. 14B, 15B, and 16B are cross-sectional views taken along line BB in FIGS. 14A, 15A, and 16A, respectively. FIG. 17 is a diagram showing a state when the element substrate 61 (element main body portion 60) and the sealing base material are bonded together.

First, a non-alkali glass having a thickness of 0.7 mm (CAGING EAGLE XG) was cut into a size of 60 × 60 mm to produce a sealing substrate 80.

Next, as shown in FIGS. 14A and 14B, tapered through

holes

80a and 80b were formed at two predetermined locations of the sealing substrate 80 by sandblasting. At this time, a blast material was continuously sprayed onto the sealing substrate 80 with a line width of about 20 μm to form a through hole. Specifically, while the blasting material spraying angle with respect to the surface of the sealing substrate 80 is smaller than 90 degrees and the blasting material spraying direction is rotated around the central axis of the through hole, the sealing substrate 80 Tapered through-holes were formed by continuously spraying a blasting material so as to cut through. In this example, a tapered through hole having one opening diameter of 1 mm and the other opening diameter of 0.7 mm was formed.

In this example, one through hole 80a is provided in the vicinity of one side of the sealing substrate 80 (in the vicinity of the left side in FIG. 14A), and in the vicinity of the side opposite to the side (on the right side in FIG. 14A). The other through hole 80b is provided in the vicinity of the side). At this time, one through hole 80a was formed at a position facing a region of the lead electrode portion of the anode 2 (a region where the organic light emitting functional layer 71 was not formed). The other through hole 80b was formed at a position facing the cathode lead electrode 70a.

FIG. 14A shows an example in which each through hole is formed at the center of the corresponding side portion in the extending direction, but the present invention is not limited to this. As long as each through hole is located at a position facing the region of the corresponding extraction electrode portion, the through hole can be formed at an arbitrary position.

Next, each through-hole electrode 81 (anode through-hole electrode and cathode through-hole electrode) is formed by pouring low melting point solder (Cerasolzer Eco # 182 manufactured by Kuroda Techno) into each through-hole and then molding by machining. Was formed (state of FIGS. 15A and 15B). In this example, as shown in FIG. 15B, a truncated cone-shaped through-hole electrode 81 was formed. In this example, the through-hole electrode 81 was formed so that the through-hole electrode 81 protrudes from one surface of the sealing substrate 80 (the surface having the smaller opening diameter of the through hole 80a). In this example, the protruding amount of the through-hole electrode 81 is 0.05 to 0.15 mm. Thereafter, the sealing substrate 80 provided with the through-hole electrode 81 was subjected to ultrasonic cleaning with isopropyl alcohol. Thereafter, the cleaned sealing substrate 80 was dried with dry nitrogen gas, and further, UV ozone cleaning was performed on the dried sealing substrate 80 for 5 minutes.

Next, as shown in FIGS. 16A and 16B, a thermosetting adhesive 82 (sealing material) is uniformly applied to the surface of the cleaned sealing substrate 80 from which the through-hole electrode 81 protrudes using a dispenser. did. The thickness of the thermosetting adhesive 82 was 20 μm. In this example, bisphenol A diglycidyl ether (DGEBA), dicyandiamide (DICY), and an epoxy adduct curing accelerator (epoxy adhesive) were used as the thermosetting adhesive. In this example, the sealing substrate 80 on which the through-hole electrode and the sealing material were formed in this way was produced.

Next, the element main body 60 manufactured as described above and the sealing base material 80 on which the through-hole electrode and the sealing material are formed are bonded using a vacuum laminator whose sample stage is heated to 80 ° C. It was. At this time, as shown in FIG. 17, the thermosetting adhesive 82 (sealing material) of the sealing substrate 80 and the cathode 70 of the element main body 60 were pasted together so as to face each other. And the bonded member was heated at 130 degreeC with the hotplate for 30 minutes, and the organic EL element was manufactured.

In this example, the example in which the through-hole electrode is provided on the sealing base material in advance before the element body and the sealing base material are bonded to each other has been described. However, the present invention is not limited to this. For example, after bonding the element body and the sealing substrate, a hole that penetrates from the sealing substrate side to the electrode is provided, and the through hole is filled with a conductive filler to form a through-hole electrode. May be.

[Example 2]
In Example 2, a can-sealed organic EL element was produced. That is, an organic EL element having the same configuration as that of the organic EL element of Modification 1 shown in FIG. 5 was produced. In Example 2, the method for forming the sealing substrate and the bonding method are different from those in Example 1. However, the method for forming the element body is the same as that in Example 1. Therefore, here, only the manufacturing method and the bonding method of the sealing substrate will be described, and the description of the manufacturing method of the element main body will be omitted.

First, a commercially available soda glass having a thickness of 1.8 mm was cut into a size of 60 mm × 60 mm to prepare a sealing substrate. Next, a concave portion (spot) having a depth of 0.6 mm was formed in the central portion of one surface of the sealing substrate by sandblasting processing and etching processing. Thereby, the sealing base material was produced.

Next, in the same manner as in Example 1, tapered through holes were formed by sandblasting at two predetermined locations of the sealing substrate. 18A and 18B show a schematic configuration of a sealing substrate in which a through hole is formed. 18A is a plan view of the sealing substrate in which the through hole is formed, and FIG. 18B is a cross-sectional view taken along the line CC in FIG. 18A.

In this example, one through hole 90a is provided in the vicinity of one side of the recess 91 of the sealing substrate 90 (in the vicinity of the left side in FIG. 18A), and in the vicinity of the side of the recess 91 facing the side. The other through-hole 90b was provided (near the right side in FIG. 18A). At this time, also in this example, each through hole was formed at a position facing the corresponding region of the extraction electrode portion. At this time, a tapered through hole was formed such that the diameter of the opening of the through hole on the surface of the sealing substrate 90 on the concave portion 91 side was smaller than that on the surface opposite to the concave portion 91 side. .

Next, in the same manner as in Example 1, low-melting-point solder was filled in the through holes, and then molded by machining to produce a through-hole electrode. FIG. 19 shows a schematic cross-sectional view of a sealing substrate 90 on which through-hole electrodes are formed. Also in this example, similarly to Example 1, the through-hole electrode 93 was formed so that the through-hole electrode 93 protrudes from the surface of the sealing substrate 90 on the recess 91 side. At this time, the through-hole electrode 93 was formed so that the protruding amount of the through-hole electrode 93 from the upper surface of the outer peripheral end portion 92 was 0.1 to 0.2 mm.

Next, the sealing substrate 90 provided with the through-hole electrode 93 was subjected to ultrasonic cleaning with isopropyl alcohol. Thereafter, the cleaned sealing substrate 90 was dried with dry nitrogen gas, and UV ozone cleaning was further performed on the dried sealing substrate 90 for 5 minutes. In this example, the sealing substrate 90 provided with the through-hole electrode 93 was produced in this way.

Next, a water replenisher made of barium oxide was provided in the recess 91 of the sealing substrate 90. Specifically, high-purity barium oxide powder made by Aldrich was used as a water replenisher, and this high-purity barium oxide powder was applied to a fluororesin semi-permeable membrane (Microtex S-NTF8031Q made by Nitto Denko) with an adhesive. Affixed to the recess 91 of the sealing substrate 90.

Next, an ultraviolet curable adhesive was applied to the upper surface of the convex outer peripheral end 92 defining the recess 91 of the sealing substrate 90. And the sealing base material 90 and the element main-body part which apply | coated this adhesive agent were bonded together through the adhesive agent, and the organic EL element was produced.

[Example 3]
In Example 3, similarly to Example 1, a solid contact type organic EL element was produced. However, in this example, a commercially available soda glass having a thickness of 0.7 mm was used as a forming material for the sealing substrate. In the organic EL element of this example, the configuration other than the above configuration of the sealing substrate is the same as that of the first embodiment. In this example, an organic EL element was produced using the same method as in Example 1.

[Comparative example]
In the comparative example, similarly to Example 2, a can-sealed type organic EL element was produced. However, in this example, the through-hole electrode was provided only for the anode, and for the cathode, an opening was provided in the region of the sealing substrate facing the cathode lead electrode. FIG. 20 shows a schematic configuration plan view of the sealing substrate of this example.

In this example, as shown in FIG. 20, an opening 100b having a size sufficiently larger than the through hole 100a was provided in a region corresponding to the cathode lead electrode of the sealing substrate 100. In this example, power is supplied to the cathode directly from the outside to the cathode lead electrode exposed in the opening 100b.

In this example, the structure was the same as that of the organic EL element of Example 2 except that the opening 100b was provided in the region corresponding to the cathode lead electrode of the sealing substrate 100. The method for producing the organic EL element in this example was also the same as the method of Example 2 except that the opening 100b was provided in the sealing substrate 100. The through-hole electrode was produced by molding a low melting point solder.

[Evaluation Test 1]
An initial voltage characteristic test and a moisture resistance test were performed on each of the organic EL elements in Examples 1 to 3 and Comparative Example, and the performance of each organic EL element was compared (evaluation test). 1). The outline of the initial voltage characteristic test and the moisture resistance test is as follows.

(1) Initial voltage characteristic test In the initial voltage characteristic test, a voltage / current generator / monitor is used to apply a predetermined current to each organic EL element produced in Examples 1 to 3 and the comparative example, and the voltage at that time. Was measured. In this test, 6243 manufactured by ADC Co., Ltd. was used as the voltage / current generator / monitor, and a current of 40 mA ( ² mA / cm ² ) was passed through each organic EL element. Moreover, the measurement result (voltage value) of each organic EL element is shown as a relative value with respect to the reference with the measurement result of Example 2 as the reference (100%). This evaluation standard is used in the same manner in evaluation tests 2 to 4 described later.

(2) Moisture resistance test In the moisture resistance test, each organic EL device produced in Examples 1 to 3 and Comparative Example was stored for 300 hours in an environment of 60 ° C and 90% relative humidity. The comparative evaluation of the magnitude | size and the evaluation of the change of a drive voltage were performed.

(A) Evaluation of non-light emitting part Before and after storing the organic EL element, a light emitting image of the organic EL element was taken using a commercially available digital single lens reflex camera (using a commercially available macro lens). Then, predetermined image processing was performed on the captured light emitting image, and the increase in the non-light emitting area was evaluated.

In addition, the evaluation value calculated by the following formula was used for evaluation of deterioration based on the change in the size of the non-light-emitting portion.
100 × [(light emitting area before storage under high humidity) − (light emitting area after storage under high humidity)] / (light emitting area before storage under high humidity)
In the said evaluation value, it shows that there are few increases of a non-light-emission part, and moisture resistance is so high that the value is small.

(B) Change in drive voltage The change in drive voltage was measured before and after storage of the organic EL element. In this measurement, similarly to the measurement of the initial voltage, a current of 40 mA was passed through the organic EL element, and the voltage at that time was measured.

The evaluation value calculated by the following formula was used for evaluation of deterioration based on the change in drive voltage before and after storage.
100 x (Voltage value after storage) / (Voltage value before storage)
In addition, in the said evaluation value, the raise of a drive voltage is so small that the value is small, and it shows that moisture resistance is high.

The results of the evaluation test 1 described above are shown in Table 1 below. In addition, “solid sealing” described in the column of the sealing form in Table 1 below means solid contact sealing, and “vertical hole” in the column of power feeding method means a through-hole electrode.

As is clear from the results in Table 1, it was found that the organic EL elements of Examples 1 to 3 both improved the initial voltage characteristics and the moisture resistance compared to the organic EL elements of the comparative examples. That is, it was found that both the initial voltage characteristics and the moisture resistance are improved by feeding both the anode and the cathode through the through-hole electrodes as in the organic EL elements of Examples 1 to 3.

[Example 4]
In Example 4, similarly to Example 1, a solid contact type organic EL element was produced. However, in this example, metal nanoparticles were used as the conductive filler for forming the through-hole electrode. Silver nano paste (Daiken Chemical Industry Co., Ltd .: NAG-10) was used as the metal nanoparticles. The firing condition of the silver nanopaste was 300 ° C. for 30 minutes.

In the organic EL element of this example, the configuration other than the use of silver nanopaste as the conductive filler is the same as the corresponding configuration of the organic EL element of Example 1. In this example, an organic EL element was produced in the same manner as in Example 1, and the shape of the through-hole electrode was the same as that in Example 1 (conical frustum shape).

[Example 5]
In Example 5, similarly to Example 1, a solid contact type organic EL element was produced. However, in this example, a low melting point alloy (manufactured by Fuji Metal Industry Co., Ltd .: No. 10 (42% tin, 58% bismuth, melting point 138 ° C.)) was used as the conductive filler for forming the through-hole electrode. .

In the organic EL element of this example, the structure other than the low melting point alloy used for the conductive filler is the same as the corresponding structure of the organic EL element of Example 1. In this example, an organic EL element was produced in the same manner as in Example 1, and the shape of the through-hole electrode was the same as that in Example 1 (conical frustum shape).

[Evaluation Test 2]
In the evaluation test 2, an initial voltage characteristic test and a moisture resistance test were performed on the organic EL elements of Examples 4 and 5 described above in the same manner as in the evaluation test 1, and the performance of each organic EL element was compared. The evaluation results are shown in Table 2 below. In Table 2, the evaluation results of Example 1 are also shown for comparison.

As is apparent from Table 2, the organic EL elements of Examples 1, 4 and 5 have both improved initial voltage characteristics and moisture resistance as compared with the organic EL elements of Comparative Examples shown in Table 1 above. I understood. That is, it was found that both the initial voltage characteristics and the moisture resistance are improved by using metal nanoparticles or a low melting point alloy in addition to the low melting point solder as the conductive filler for forming the through-hole electrode.

Also, from Table 2, it was found that the best characteristics were obtained when metal nanoparticles were used as the conductive filler for forming the through-hole electrode.

[Example 6]
In Example 6, similarly to Example 1, a solid contact type organic EL element was produced. However, in this example, the shape of the tip portion of the through-hole electrode was different from the shape (conical frustum shape) of the tip portion of the through-hole electrode of Example 1.

FIG. 21 shows a schematic cross-sectional view of a sealing substrate on which through-hole electrodes in this example are formed. In this example, the shape of the tip portion of the through-hole electrode 111 is conical. The dimension of the through hole 111a in which the through hole electrode 111 is formed is the same as that of the through hole 80a of the first embodiment.

In this example as well, as in Example 1, the through-hole electrode 111 was formed so that the through-hole electrode 111 protruded from the surface of the sealing substrate 110, and the protruding amount was 005 to 0.15 mm. did.

Furthermore, in this example, the through-hole 110a of the sealing substrate 110 on which the through-hole electrode 111 is provided is a tapered through-hole as in the first embodiment. The through-hole electrode 111 was formed using low melting point solder as in the first embodiment.

The configuration of the organic EL element of this example is the same as the corresponding configuration of the organic EL element of Example 1 except that the shape of the tip portion of the through-hole electrode 111 is changed. In this example, an organic EL element was produced in the same manner as in Example 1 except that the shape of the tip portion of the through-hole electrode 111 was changed.

[Example 7]
In Example 7, similarly to Example 1, a solid contact type organic EL element was produced. However, in this example, similarly to Example 6, the shape of the through-hole electrode (the shape of the tip portion) was different from the shape of the through-hole electrode of Example 1 (conical frustum shape).

FIG. 22 shows a schematic cross-sectional view of a sealing substrate on which through-hole electrodes in this example are formed. In this example, the shape of the through-hole electrode 121 (the shape of the tip portion) is a cylindrical shape having a diameter of 1.0 mm.

In this example as well, as in Example 1, the through-hole electrode 121 was formed so that the through-hole electrode 121 protruded from the surface of the sealing substrate 120, and the protruding amount was 005 to 0.15 mm. did.

Furthermore, in this example, the through hole 120a of the sealing substrate 120 on which the through hole electrode 121 is provided is also a cylindrical through hole (diameter is 1.0 mm). The through-hole electrode 121 was formed using low melting point solder as in the first embodiment.

In the organic EL element of this example, the configuration other than that of changing the shape of the through-hole electrode 121 is the same as the corresponding configuration of the organic EL element of Example 1. In this example, an organic EL element was produced in the same manner as in Example 1 except that the shape of the through-hole electrode 121 was changed.

[Evaluation Test 3]
In the evaluation test 3, an initial voltage characteristic test and a moisture resistance test were performed on the organic EL elements of Examples 6 and 7 described above in the same manner as in the evaluation test 1, and the performance of each organic EL element was compared. Table 3 below shows the evaluation results. In Table 3 below, the evaluation results of Example 1 are also shown for comparison.

As is apparent from Table 3, the organic EL elements of Examples 1, 6 and 7 have both improved initial voltage characteristics and moisture resistance as compared with the organic EL elements of the comparative examples shown in Table 1 above. I understood. That is, it was found that both the initial voltage characteristics and the moisture resistance are improved even when the shape of the tip portion of the through-hole electrode is changed.

Further, from Table 3, it was found that the sharper the tip portion of the through-hole electrode is, the more the initial voltage characteristics and the moisture resistance are improved.

[Example 8]
In Example 8, similarly to Example 1, a solid contact type organic EL element was produced. However, in this example, the through hole of the sealing substrate was formed by an etching process using hydrofluoric acid. The shape of the through hole was a columnar shape as in Example 7.

In this example, an organic EL element was produced in the same manner as in Example 7 except that the through hole of the sealing substrate was formed by etching. The through-hole electrode was formed using low melting point solder as in Example 7.

[Example 9]
In Example 9, similarly to Example 1, a solid contact type organic EL element was produced. However, in this example, the through hole of the sealing substrate was formed by machining using a diamond drill. The shape of the through hole was a columnar shape as in Example 7.

In this example, an organic EL element was produced in the same manner as in Example 7 except that the through hole of the sealing substrate was formed using a diamond drill. The through-hole electrode was formed using low melting point solder as in Example 7.

[Evaluation Test 4]
In the evaluation test 4, an initial voltage characteristic test and a moisture resistance test were performed on each organic EL element of Examples 8 and 9 described above in the same manner as in the evaluation test 1, and the performance of each organic EL element was compared. The evaluation results are shown in Table 4 below. In Table 4 below, the evaluation results of Example 7 are also shown for comparison.

As is clear from Table 4, it was found that both the initial voltage characteristics and the moisture resistance of the organic EL elements of Examples 7 to 9 were improved as compared with the organic EL elements of the comparative examples shown in Table 1 above. . That is, it was found that both the initial voltage characteristics and the moisture resistance are improved even when the through hole forming method of the sealing substrate is changed.

Also, from Table 4, it was found that the best characteristics can be obtained when sandblasting is used as a method for forming the through hole of the sealing substrate. This is because when the through hole is formed by sandblasting, the size of the unevenness of the side wall portion of the sealing substrate that defines the through hole becomes larger, the adhesion between the side wall portion and the through hole electrode increases, This is thought to be due to improved stopping characteristics.

From the results of the various evaluation tests described above, as in the organic EL element of the present invention, the entire element substrate is covered with the sealing substrate, and the anode and cathode are both fed via the through-hole electrode. As a result, it was found that high temperature and high humidity storage stability can be maintained, and an increase in driving voltage can be suppressed.

DESCRIPTION OF SYMBOLS 1 ... Element board | substrate, 2 ... Anode, 3 ... Organic light emission functional layer, 4 ... Cathode, 4a ... Cathode extraction electrode, 5 ... Sealing base material, 5a ... Through-hole, 6 ... Sealing material, 7 ... Through-hole electrode for anode 8 through-hole electrode for cathode, 10 organic EL element, 20 planar light emitter, 21 support substrate, 22 adhesive member

Claims

An element substrate;
A first electrode formed on the element substrate;
An organic compound layer formed on the first electrode and including a light emitting layer;
A second electrode formed on the organic compound layer;
An insulating sealing material provided so as to cover the surface of the element base on the second electrode side;
The insulating sealing material and one element of the element base member are provided in a part of a region facing the first electrode in the thickness direction of the member, and the tip is the first electrode. A first through-hole electrode in contact with,
A second through-hole electrode provided in a part of a region of the member facing the second electrode so as to penetrate in the thickness direction of the member and having a tip contacting the second electrode. Organic electroluminescence device.
Furthermore, an adhesive provided over the entire surface of the element base on the second electrode side,
The organic electroluminescent element according to claim 1, wherein the insulating sealing material is bonded to the surface of the element base on the second electrode side via the adhesive.
A first through hole and a second through hole are formed in an arrangement region of the first through hole electrode and the second through hole electrode of one member of the insulating sealing material and the element base material, respectively. The first through hole and the second through hole are both tapered holes, and the opening area of the first through hole and the second through hole on the organic compound layer side is the organic compound layer side. The organic electroluminescence element according to claim 1, wherein the organic electroluminescence element is smaller than the opening area on the opposite side of the electrode.
The organic electroluminescence device according to any one of claims 1 to 3, wherein a shape of a tip portion of the first through-hole electrode and a shape of a tip portion of the second through-hole electrode are both conical.
The organic electroluminescence device according to any one of claims 1 to 4, wherein both the first through-hole electrode and the second through-hole electrode are formed of silver nanoparticles.
The organic electro according to any one of claims 1 to 5, wherein a difference between a linear expansion coefficient of the element base material and a linear expansion coefficient of the insulating sealing material is 10 × 10 -6 / ° C or less. Luminescence element.
The organic electroluminescence element according to any one of claims 1 to 6, wherein the first through-hole electrode and the second through-hole electrode are provided in the insulating sealing material.
An element substrate, a first electrode formed on the element substrate, an organic compound layer formed on the first electrode and including a light emitting layer, and a second formed on the organic compound layer An electrode, an insulating sealing material provided so as to cover the surface of the element base on the second electrode side, and the first electrode of one member of the insulating sealing material and the element base A first through-hole electrode that penetrates in a thickness direction of the member and has a tip in contact with the first electrode; and the second electrode of the member; A plurality of organic electroluminescence elements having a second through-hole electrode that is provided in a part of the opposing region so as to penetrate in the thickness direction of the member and whose tip is in contact with the second electrode;
A planar light-emitting body comprising: a support member configured to support the plurality of organic electroluminescence elements arranged in a predetermined form.
Forming a first electrode on the element substrate;
Forming an organic compound layer including a light emitting layer on the first electrode;
Forming a second electrode on the organic compound layer;
Insulating sealing material for sealing the surface of the element base on the second electrode side, a part of the region facing the first electrode of one member of the element base, and the Forming a first through hole and a second through hole in a part of a region of the member facing the second electrode,
The first member extends along the thickness direction of the member and protrudes from the surface of the member on the organic compound layer side, and is electrically connected to the first electrode and the second electrode, respectively. Forming a through hole electrode and a second through hole electrode so as to seal the first through hole and the second through hole, respectively;
An insulating sealing material is provided on the element base so as to seal the surface of the element base on the second electrode side. A method for manufacturing an organic electroluminescence element.
Forming the first through hole and the second through hole in the insulating sealing material;
The insulating sealing material on which the first through-hole electrode and the second through-hole electrode are formed is formed on the element substrate so as to seal a surface of the element substrate on the second electrode side. The manufacturing method of the organic electroluminescent element of Claim 9.
The method for manufacturing an organic electroluminescence element according to claim 10, wherein the first through hole and the second through hole are formed by sandblasting.
The organic electroluminescent element according to any one of claims 9 to 11, wherein the insulating sealing material is bonded to the entire surface of the element base on the second electrode side via an adhesive. Production method.
The method for manufacturing an organic electroluminescent element according to claim 12, wherein a sheet-like adhesive is used as the adhesive.