JP2003187975A - Organic electroluminescent device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an organic EL device in which deterioration of a color conversion layer can be suppressed. <P>SOLUTION: The organic EL device 100 comprises, on a support substrate 2 in the direction of taking out light as shown by an arrow, a TFT 6 embedded in the electric insulating membrane 4, an insulating membrane between the layers 8, an organic EL element 16, an oxygen cut-off layer 20, an oxygen supply layer 22, and a color conversion membrane 28. When oxygen is supplied from the oxygen supply layer 22 to the color conversion layer 26 contained in the color conversion membrane 28, deterioration of the fluorescent intensity of the color conversion layer 26 at the time of continuous drive is prevented. And since the oxygen cut-off layer 20 is provided between the oxygen supply layer 22 and the organic EL element 16, the organic EL element 16 is not deteriorated as oxygen does not come from the oxygen supply layer 22 to the organic EL element 16. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an organic electroluminescence (EL) light emitting device which is preferably used as a light source of a display device (display) for a consumer or an industrial use or a printer head.

[0002]

2. Description of the Related Art Conventionally, EL devices utilizing electroluminescence are
Since it is capable of self-light emission, has high visibility, and has a characteristic of being excellent in impact resistance because it is completely solid, its use as a light emitting element in various display devices has been drawing attention. In particular, an organic EL light-emitting device using an organic compound as a light-emitting material can be applied to a large amount because the applied voltage can be significantly reduced, and the device can be thin and small in size and power consumption can be reduced. Is aimed at.

In these organic EL light emitting devices, a color conversion layer for converting the light emitted from the organic EL element into light of different wavelengths is provided to enable full color display. For example, the color conversion layer converts light that mainly contains blue light into red light or green light to realize full-color display with the three primary colors of blue, red, and green. Here, the color conversion layer is composed of only a fluorescent dye or a fluorescent dye and a binder resin.

[0004]

When the color conversion layer is irradiated with the light emitted from the organic EL element, which is the excitation light, the fluorescent dye in the ground state absorbs the excitation light and becomes the excited singlet state. This excited singlet state returns to the ground state while emitting fluorescence after a lifetime of several to several hundred nanoseconds has passed. Due to such a phenomenon, the excitation light is efficiently converted into light having a desired wavelength. The excited singlet state is an electronically active state, but its lifetime is short, and therefore it tends to be difficult to interact with other fluorescent dyes or binder resins. However, the fluorescent dye excited to the singlet state always transits to the excited triplet state by intersystem crossing with a certain probability. The excited triplet state has a longer excitation lifetime of several hundred nanoseconds to several thousand microseconds than the excited singlet state, and therefore the dye structure is likely to change due to the interaction with other fluorescent dyes or binder resins. Therefore, when the color conversion layer is continuously irradiated with the excitation light for a long time, there is a problem that the fluorescence gradually decreases, that is, the color conversion efficiency decreases (deteriorates). Therefore, an object of the present invention is to provide an organic EL light emitting device that can suppress deterioration of the color conversion layer.

[0005]

Here, the present inventors
As a result of earnest studies on the deterioration countermeasure of the color conversion layer, in order to suppress the deterioration of the color conversion layer, if an additive that receives energy from the fluorescent dye in the excited triplet state and returns the fluorescent dye to the ground state is added, I found something good. Moreover, it has been found that for that purpose, the lowest excited state of the additive, that is, the lowest excited triplet energy level, must be lower than the triplet energy level of the fluorescent dye. On the other hand, oxygen is known as a substance that receives energy from the triplet state of a fluorescent dye. The reason is that the ground state of oxygen is a triplet state and the probability of being an excited triplet state is high. In fact, it was found that when the color conversion layer was irradiated with excitation light in the presence of oxygen, deterioration of the color conversion layer was suppressed.

Therefore, an organic EL element including an organic EL element, a color conversion layer for converting light emitted from the organic EL element into light of different wavelengths, and an oxygen supply layer for supplying oxygen to the color conversion layer
An L light emitting device is provided. As a result, since oxygen can be supplied to the color conversion layer by the oxygen supply layer, deterioration of fluorescence intensity during continuous driving of the color conversion layer can be suppressed (the life of the color conversion layer can be extended). However, since the work function of the organic EL element, particularly the electron injection portion (cathode or electron injection layer) of the organic EL element is small, it is oxidized by the presence of oxygen, and the electron injection property is significantly deteriorated. In addition, since the organic light emitting medium of the organic EL element is composed of an organic substance, it is more likely to emit oxygen radicals during driving than an inorganic substance.
It is easily oxidized and decomposed and deteriorated. That is, it was found that the presence of oxygen easily promotes the deterioration of the organic EL element. Therefore, particularly in a colorized organic EL element in which a color conversion layer and an organic EL element are combined, it is more preferable to have an oxygen blocking layer between the oxygen supply layer and the organic EL element. That is, by providing the oxygen blocking layer, it is possible to prevent the organic EL element from being oxidized by oxygen supplied from the oxygen supply layer.

As a specific structure of the above organic EL light emitting device, an oxygen supply layer and a color conversion layer may be laminated.
The oxygen supply layer and the color conversion layer may be juxtaposed.

Another aspect of the present invention is an organic EL element, a color conversion layer for converting light emitted from the organic EL element into light of different wavelengths, and an oxygen permeable substrate for transmitting oxygen from the outside to the color conversion layer. It is an organic EL light emitting device including. Since the oxygen permeable substrate allows oxygen to be supplied from the atmosphere to the color conversion layer through the substrate, the life of the color conversion layer is extended. The meaning of the oxygen permeable substrate is a substrate that can supply oxygen to the color conversion layer from the atmosphere, and may be a substrate having a high oxygen transmission amount, or a substrate that does not affect the manufacturing and display quality of the light emitting device. An oxygen supply hole may be provided in a part of the. For example,
Oxygen supply holes (through holes in the substrate) may be provided around the display area of the substrate.

When the film thickness of the color conversion layer is H (μm) and the oxygen transmission amount of the oxygen permeable substrate is P (cc / m ² · day), P / H> 0.03 is satisfied. preferable.
More preferably P / H> 0.3, and even more preferably P
/ H> 3. Here, H is the maximum film thickness of the color conversion layer, and the oxygen transmission amount is ASTM D3985, ASTM
It is defined by the test method according to D1434, JIS Z1707 and JIS K7126. The amount of oxygen permeation can be adjusted by the material of the oxygen permeable substrate, its plate thickness, and the surface treatment state of the substrate (for example, oxygen enriched film treatment on the outside air side).
One of the reasons why the deterioration of the color conversion function can be suppressed more effectively by setting P / H> 0.03 is the following mechanism for preventing deterioration of the fluorescent dye. However, the present invention is not limited to the following mechanism for preventing deterioration of the fluorescent dye. The fluorescent dye in the color conversion layer in the excited triplet state transfers energy to oxygen and returns to the stable ground state, and the oxygen that has received the energy is thermally radiatively deactivated and becomes a normal triplet basis. It is thought to return to the state. That is, the fluorescent dye molecules in the color conversion layer are excited by the light emitted from the organic EL element, and even if the excited triplet state undergoes transition due to intersystem crossing with a certain probability, it deteriorates due to the presence of oxygen molecules. It is considered that the deterioration of the color conversion layer is suppressed by repeating the cycle of returning to the ground state instead. Therefore, it is considered preferable that the number of oxygen molecules that receive energy from the fluorescent dye is equal to or larger than the number of fluorescent dye molecules in the color conversion layer. Here, the oxygen permeation amount of the oxygen permeable substrate is P (cc / m ² · day), the area in contact with the color conversion layer is A (m ² ), the film thickness of the color conversion layer is H (μm), and the color conversion layer is The fluorescent dye concentration inside is C (mol / m ³ ). 1
At day (normal pressure, normal temperature (20 ° C.)), oxygen molecules more than the number of molecules of the fluorescent dye in the color conversion layer permeate the oxygen permeable substrate,
If supplied to the color conversion layer, P (cc / m ² · day) × A (m ² ) / 24000
(Cc) ≧ A (m ² ) × H (μm) × 10 ⁻⁶ × C (m
ol / m ³ ) is satisfied. By the way, in order for the fluorescent dye in the color conversion layer to exhibit a sufficient color conversion ability (to efficiently absorb the light of the organic EL element and efficiently convert it into fluorescence), the fluorescent dye concentration is set to 1
× 10 ⁻³ (mol / l), that is, 1 (mol / m ³ ).
It is often necessary to do more. Therefore, P / H ≧
It is considered that the deterioration of the color conversion layer can be suppressed in many cases by setting 0.024. However, depending on the type of fluorescent dye, the fluorescent dye concentration necessary for exhibiting sufficient color conversion ability may not be 1 (mol / m ³ ) or more. In such a case, the oxygen permeation amount may be adjusted appropriately using P / H calculated from the above formula as a guide.
Further, it is considered that supplying excess oxygen to the color conversion layer in a shorter time can more reliably suppress the deterioration of the fluorescent dye in consideration of diffusion of oxygen into the color conversion layer. Therefore,
P / H is preferably as large as possible.

Further, 50% or more of the surface area of the color conversion layer is
It is preferably in contact with the oxygen permeable substrate. More preferably, 60% or more is in contact with the oxygen permeable substrate. When oxygen is supplied to the color conversion layer, it is preferable that the contact area between the color conversion layer and the oxygen permeable substrate is large because the rate of diffusion of oxygen into the entire color conversion layer is increased. The "surface area of the color conversion layer" includes not only the lower surface of the color conversion layer, but also the side surface and any upper surface. For example, the color conversion layer may be embedded in the oxygen permeable substrate, and the lower surface and the side surface of the color conversion layer may be in contact with the oxygen permeable substrate. Furthermore, the interface between the color conversion layer and the oxygen permeable substrate may be an uneven surface, and
The color conversion layer may have a trapezoidal shape (long side is an interface with the oxygen permeable substrate).

Further, it is preferable to have an oxygen barrier layer between the oxygen permeable substrate and the organic electroluminescence element. By providing the oxygen blocking layer, it is possible to prevent the organic EL element from being oxidized by oxygen that permeates from the oxygen permeable substrate.

Further, it is preferable that the oxygen permeable substrate is optically transparent. By making the oxygen permeable substrate transparent, the fluorescence emission from the color conversion layer can be efficiently extracted.

The oxygen permeable substrate is preferably made of porous glass. By using porous glass,
Through this substrate, oxygen can be supplied to the color conversion layer from the atmosphere, and the mechanical strength of the light emitting device can be increased while maintaining transparency. The meaning of the porous glass is not limited to the meaning that the entire substrate is porous, and a part of the substrate may have a porous portion.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Members of the organic EL light emitting device of the present invention will be described below. 1. Organic EL Element In an organic EL element, an anode layer and a cathode layer, which are electrodes, sandwich an organic light emitting medium. (1) Organic Light-Emitting Medium An organic light-emitting medium can be defined as a medium including an organic EL light-emitting layer capable of EL emission by recombination of electrons and holes. Such an organic light emitting medium can be formed by stacking the following layers on the anode layer, for example. Organic EL light emitting layer hole injection layer / organic EL light emitting layer organic EL light emitting layer / electron injection layer hole injection layer / organic EL light emitting layer / electron injection layer organic semiconductor layer / organic EL light emitting layer organic semiconductor layer / electron barrier layer / Organic EL light-emitting layer Hole injection layer / organic EL light-emitting layer / adhesion improving layer Among these, the structure of (1) is usually preferably used since higher emission brightness can be obtained and durability is excellent.

(I) Material As the light emitting material in the organic light emitting medium, for example, p-
Quarter phenyl derivatives, p-quinque phenyl derivatives, benzothiazole compounds, benzimidazole compounds, benzoxazole compounds, metal chelated oxinoid compounds, oxadiazole compounds, styrylbenzene compounds, distyrylpyrazine derivatives, butadiene compounds Compounds, naphthalimide compounds, perylene derivatives, aldazine derivatives, pyrazirine derivatives, cyclopentadiene derivatives, pyrrolopyrrole derivatives, styrylamine derivatives, coumarin compounds, aromatic dimethylidyne compounds, metal complexes having 8-quinolinol derivatives as ligands, Examples thereof include one kind alone or a combination of two or more kinds such as polyphenyl compounds.

Among these organic light emitting materials, 4,4'-bis (2,2-di-t-butylphenylvinyl) biphenyl (DTBPBBi) and 4,4 'as aromatic dimethylidyne compounds are used. -Bis (2,2-diphenylvinyl) biphenyl (DPVBi), and derivatives thereof are more preferable. Furthermore, an organic light-emitting material having a distyrylarylene skeleton or the like is used as a host material, and the host material is doped with a strong fluorescent dye from blue to red as a dopant, for example, a coumarin-based material, or a fluorescent dye similar to the host. It is also preferable to use in combination. More specifically, it is preferable to use DPVBi described above as the host material and N, N-diphenylaminobenzene (DPAVB) as the dopant. In addition to the low molecular weight material (number average molecular weight less than 10,000) as described above, it is also preferable to use a polymer material (number average molecular weight 10,000 or more). Specifically, polyarylene vinylene and its derivatives (PP
V), polyfluorene and its derivatives, fluorene-containing copolymers and the like.

(Ii) Thickness The thickness of the organic light emitting medium is not particularly limited, but for example, the thickness is preferably 5 nm to 5 μm. The reason for this is that when the thickness of the organic light emitting medium is less than 5 nm, the emission brightness and durability may decrease, while
This is because when the thickness of the organic light emitting medium exceeds 5 μm, the value of the applied voltage may increase. For this reason, the thickness of the organic light emitting medium is more preferably 10 nm to 3 μm, further preferably 20 nm to 1 μm.

(2) Electrode Hereinafter, the anode layer and the cathode layer as electrodes will be described. In the present invention, the electrode corresponds to both the lower electrode and the upper electrode depending on the configuration of the organic EL light emitting device.

(I) Anode Layer For the anode layer, it is preferable to use a metal, an alloy, an electrically conductive compound or a mixture thereof having a high work function (for example, 4.0 eV or more). Specific examples of these are:
Indium tin oxide (ITO), indium zinc oxide (IZO), indium copper (CuIn), tin oxide (SnO ₂ ), zinc oxide (ZnO), gold, platinum, palladium or the like alone or in combination of two or more. Is mentioned.

When the anode layer is used as an electrode for extracting light, it is preferable that the anode layer is a transparent electrode. As the material of the transparent electrode, ITO, IZO,
Examples of the transparent conductive material include CuIn, SnO ₂ , and ZnO. Of these, IZO is more preferable because it is non-crystalline, has high surface smoothness, and has fewer defects in the organic EL.

As a method for forming the anode layer, a vacuum vapor deposition method, a sputtering method, an ion plating method, an electron beam vapor deposition method, a CVD method (Chemical Vap) are used.
orDeposition), MOCVD method (Meta
l Oxide Chemical Vapor Depo
and a method capable of forming a film in a dry state such as a plasma CVD method.

The thickness of the anode layer is also not particularly limited, but is preferably 10 to 1,000 nm, and more preferably 10 to 200 nm.

(Ii) Cathode Layer For the cathode layer, it is preferable to use a metal, an alloy, an electrically conductive compound having a low work function (for example, less than 4.0 eV), or a mixture or inclusion thereof. Specific examples thereof include sodium, sodium-potassium alloy, cesium, magnesium, lithium, magnesium-silver alloy, aluminum, aluminum oxide, aluminum-lithium alloy, indium, rare earth metal, and these metals and organic light emitting medium materials. Mixtures, and mixtures of these metals and electron injection layer materials may be used alone or in combination of two or more.

The thickness of the cathode layer is not particularly limited as in the case of the anode layer, but is specifically 10
It is preferable that it is ~ 1,000 nm, and it is 10-200 n.
More preferably, it is m.

2. Color conversion layer The color conversion layer has a function of absorbing light emitted from the organic EL element and emitting fluorescence of longer wavelength. For example, light mainly containing blue light is converted into green light or red light. In addition to the color conversion layer, a color filter may be included to improve color reproducibility.

Each color conversion layer is a light emitting region of an organic EL device,
For example, it is preferable that they are arranged corresponding to the position of the intersection of the anode and the cathode. With this configuration, when the organic EL light emitting layer at the intersection of the anode and the cathode emits light, each color conversion layer receives the light, and the emission of different colors (wavelengths) can be extracted to the outside. It will be possible. In this case, in particular, when the organic EL element emits blue light and the color conversion layer is capable of converting to green and red light emission, even one organic EL element emits blue light.
This is preferable because the three primary colors of light of green and red can be obtained and full-color display is possible.

(1) Material The material of the color conversion layer is not particularly limited. For example, the color conversion layer is composed of a fluorescent dye and a binder resin, or only a fluorescent dye. And / or a solid state resin dissolved or dispersed in a binder resin.

Explaining concrete fluorescent dyes, 1,4-bis (2-methylstyryl) benzene (Bis-MBS) is used as a fluorescent dye for converting near-ultraviolet light to violet emission into blue emission in an organic EL device. ), Trance
Examples thereof include stilbene dyes such as 4,4′-diphenylstilbene (DPS) and coumarin dyes such as 7-hydroxy-4-methylcoumarin (coumarin 4).

Further, regarding the fluorescent dye in the case of converting the blue, blue-green or white emission in the organic EL element into green emission, for example, 2,3,5,6-1H, 4H-tetrahydro-8-triflor is used. Methyl quinolizino (9,9
a, 1-gh) Coumarin (coumarin 153), 3-
Coumarin dyes such as (2′-benzothiazolyl) -7-diethylaminocoumarin (coumarin 6) and 3- (2′-benzimidazolyl) -7-N, N-diethylaminocoumarin (coumarin 7), and other coumarin dyes. Naphthalimide dyes such as Basic Yellow 51, Solvent Yellow 11 and Solvent Yellow 116 can be mentioned.

Further, regarding the fluorescent dye in the case of converting the blue to green emission or the white emission in the organic EL device into the orange to red emission, for example, 4-
Cyanine dyes such as dicyanomethylene-2-methyl-6- (p-dimethylaminostyrylyl) -4H-pyran (DCM), 1-ethyl-2- (4- (p-dimethylaminophenyl) -1,3. -Butadienyl) -pyridinium-perchlorate (pyridine 1) and the like,
Rhodamine dyes such as Rhodamine B and Rhodamine 6G,
Other examples include oxazine dyes.

Further, various dyes (direct dyes, acid dyes,
Basic dyes, disperse dyes, etc.) can also be selected as fluorescent dyes if they have fluorescence. In addition, a pigment is prepared by previously kneading a fluorescent dye into a pigment resin such as polymethacrylic acid ester, polyvinyl chloride, vinyl chloride vinyl acetate copolymer, alkyd resin, aromatic sulfonamide resin, urea resin, melanin resin, benzoguanamine resin. It may be a converted version.

On the other hand, the binder resin is preferably a transparent material (having a light transmittance of 50% or more in visible light). Examples thereof include transparent resins (polymers) such as polymethylmethacrylate, polyacrylate, polycarbonate, polyvinyl alcohol, polyvinylpyrrolidone, hydroxyethyl cellulose, carboxymethyl cellulose and the like.

A photosensitive resin to which the photolithography method can be applied is also selected in order to dispose the fluorescent medium on a plane. Examples thereof include photocurable resist materials having a reactive vinyl group such as acrylic acid type, methacrylic acid type, polyvinyl cinnamate type, and ring rubber type. When using the printing method, a printing ink (medium) using a transparent resin is selected. For example, polyvinyl chloride resin, melamine resin, phenol resin, alkyd resin, epoxy resin, polyurethane resin, polyester resin, maleic acid resin, polyamide resin monomer, oligomer, polymer, polymethylmethacrylate, polyacrylate, polycarbonate, polyvinyl alcohol. Transparent resins such as polyvinylpyrrolidone, hydroxyethyl cellulose, and carboxymethyl cellulose can be used.

(2) Forming Method When the color conversion layer is mainly composed of a fluorescent dye, it is preferable to form the film by vacuum vapor deposition or sputtering through a mask that can obtain a desired pattern of the color conversion layer. On the other hand, when the color conversion layer is composed of a fluorescent dye and a resin, the fluorescent dye, the resin and a suitable solvent are mixed, dispersed or solubilized to obtain a liquid material, and the liquid material is spin-coated, roll-coated,
A film is formed by a method such as a cast method, and then a pattern of a desired color conversion layer is formed by a photolithography method, or a pattern is formed by a method such as screen printing or an inkjet method to form a color conversion layer. Preferably.

(3) Thickness The thickness of the color conversion layer is not particularly limited as long as it sufficiently receives (absorbs) the light emitted from the organic EL element and does not interfere with the function of generating fluorescence. , For example, 1
The thickness is preferably 0 nm to 1,000 μm, and 0.1
It is more preferable that the thickness is from 500 μm to 500 μm.
More preferably, it is 100 μm. The reason for this is
This is because if the thickness of the color conversion layer is less than 10 nm, the mechanical strength may decrease and it may be difficult to stack the layers. On the other hand, if the thickness of the color conversion layer exceeds 1 mm, the light transmittance may be significantly reduced, the amount of light that can be extracted to the outside may be reduced, or it may be difficult to reduce the thickness of the organic EL light emitting device. .

3. Light-shielding layer The light-shielding layer shields unnecessary light emitted from the organic EL element, prevents color mixing, and improves viewing angle characteristics. Examples of materials for the light-shielding layer include the following metals and black dyes. The types of metals are Ag, Al,
Au, Cu, Fe, Ge, In, K, Mg, Ba, N
a, Ni, Pb, Pt, Si, Sn, W, Zn, Cr,
One or more metals or alloys of Ti, Mo, Ta, stainless steel, etc. may be mentioned. Also, oxides of the above metals,
Nitride, sulfide, nitrate, sulfate or the like may be used, and carbon may be contained as necessary. The material of the light shielding layer is formed into a transparent substrate by a method such as a sputtering method, a vapor deposition method, a CVD method, an ion plating method, an electrodeposition method, an electroplating method, a chemical plating method, and a photolithography method. It is possible to form a pattern of the light-shielding layer (separately arranged in a plane) by performing patterning using the above method. Further, examples of the black dye include carbon black, titanium black, aniline black, and those obtained by mixing the above color filter dyes to blacken. The black dye or the metal material is dissolved or dispersed in the binder resin used in the color conversion layer to form a solid state, which is then patterned in the same manner as the color conversion layer to form a patterned light-shielding layer. Here, the light shielding layer may be a part of the oxygen permeable substrate. As a result, 50% or more of the surface area of the color conversion layer contacts the oxygen permeable substrate, which is preferable.

The thickness of the light-shielding layer is usually in the range of 10 nm to 1 mm, preferably in the range of 1 μm to 1 mm,
It is more preferably a value within the range of 5 μm to 100 μm. Further, the surface shape of the light shielding layer may be a lattice shape or a stripe shape, but a lattice shape is more preferable. The transmittance of the light-shielding layer is preferably 10% or less, and more preferably 1% or less in a region that emits light of the organic EL element or light from the color conversion layer, that is, light in a visible region having a wavelength of 400 nm to 700 nm. If it exceeds 10%, the light of the EL element or the light from the color conversion layer may enter not only the front color conversion layer but also the adjacent color conversion layer, and the function as the light shielding layer may not be sufficiently fulfilled. In addition, at least on the side surface of the light-shielding layer that is in contact with the color conversion layer, the wavelength is 400 nm to 700 n.
The reflectance of light in the visible region of m is 10% or more, and more preferably 50% or more. By controlling the reflectance within such a range, the light from the color conversion layer can be effectively extracted, the brightness of the organic EL display device can be increased, and the visibility can be further improved. In order to adjust the reflectance of light, the metal material is used as it is as the pattern of the light-shielding layer, or a pattern of the light-shielding layer consisting of a black dye alone or a black dye and a binder resin, the metal material is sputtered, It can be adjusted by forming a film by a method such as a vapor deposition method, a CVD method or an ion plating method.

4. Oxygen Supply Layer The oxygen supply layer is not limited as long as it can supply oxygen to the color conversion layer. As a specific example of the oxygen supply layer,
Liquid with sufficient oxygen bubbling (eg, Fluorinert, silicone oil), or gel-like substance (silicone gel, fluorogel, natural product gel, etc.), artificial blood, porphyrin, TiO ₂ , a layer containing a mixture of photocatalyst and water, etc. Is mentioned. It may also be composed of a gas containing oxygen such as air. Here, as an example in which the oxygen supply layer and the color conversion layer are arranged side by side, a part of the oxygen supply layer may be arranged in the light shielding layer portion to supply oxygen to the side surface of the color conversion layer. More specifically, the width of the light-shielding layer is gradually or gradually reduced toward the light extraction direction to form an overhang-shaped or T-shaped cross-sectional shape, and oxygen is provided in a gap between the color conversion layer. Place the feed layer. The oxygen supply layer may be included in the light shielding layer. Specific examples thereof include oxides such as manganese dioxide, potassium permanganate, and potassium chromate. Here, the thickness of the oxygen supply layer is
Depending on the definition of the L light emitting device, 0.1 μm to 1 mm,
It is preferably 0.5 μm to 100 μm, more preferably 1 μm to 20 μm. If it is smaller than 0.1 μm, oxygen is not sufficiently supplied to the color conversion layer, and if it is larger than 1 mm, the light of the organic EL element is diffused and the incidence of a desired color conversion layer is hindered. Deterioration (color bleeding,
Color mixing, viewing angle dependence).

5. Oxygen barrier In the oxygen barrier layer, the oxygen supplied from the oxygen supply layer is
Limited as long as it can block contact with the EL element
I can't. The oxygen transmission rate of the oxygen barrier layer is 0.1 cc / m^Two
・ Preferably less than day, 0.01 cc / m^Two・ Day
It is more preferably less than. As a concrete material
Examples include transparent inorganic substances, transparent resins, and sealing liquids. Well
However, transparent inorganic materials are most preferable. More specifically, Si
O_Two, SiO_x, SiO_xN_y, Si_ThreeN_Four, Al_TwoO
_Three, AlO_xN_y, TiO_Two, TiO_x, ITO (In
_TwoO_Three-SnO_Two), IZO (In_TwoO_Three-ZnO),
SnO_Two, ZnO, indium copper (CuIn), gold, white
Gold, palladium, etc., alone or in combination of two or more
And transparent inorganic substances. In this case, the organic EL
In order not to deteriorate the device or the color conversion layer, a low temperature (100
It is preferable to slow down the deposition rate at (° C or below)
Specifically, sputtering, vapor deposition, CVD, ion
A method such as plating is preferable. Also, these transparent
A clear inorganic substance is that it is amorphous.
It is preferable because it has a high blocking effect. Next, as a transparent resin
Is polyvinyl alcohol, polyvinylidene chloride, poly
Acrylonitrile, cellophane, nylon 6, polyethylene
Resins such as lenterephthalate, polytrifluorochloroethylene
, PCTFE (polychlorotrifluoroethylene),
Fluorine such as PTFE (polytetrafluoroethylene)
Resins containing are preferred. These films are biaxially stretched
It can be made into a film or coated on another general-purpose resin film.
It may be. Next, an inert liquid is used as the sealing liquid.
It is preferable because it does not deteriorate the organic EL element.
Examples thereof include fluorohydrocarbon and silicone oil.

Here, the thickness of the oxygen barrier layer depends on the definition of the organic EL light emitting device, as in the oxygen supply layer, but is 0.
1 μm to 1 mm, preferably 0.5 μm to 100 μ
m, more preferably 1 μm to 20 μm. 0.1
If it is smaller than μm, the oxygen blocking effect is not obtained, and if it is larger than 1 mm, the light of the organic EL element is diffused and the incidence of the desired color conversion layer is blocked, so that the visibility is deteriorated (color bleeding, color mixture, viewing angle Dependent.

6. Oxygen-permeable substrate The oxygen-permeable substrate is not limited as long as it can transmit oxygen to the color conversion layer through the substrate. When an oxygen permeable substrate is used as the supporting substrate, it is preferable that it has excellent mechanical strength and dimensional stability.

Examples of the oxygen permeable substrate include polycarbonate resin, acrylic resin, vinyl chloride resin, polyethylene terephthalate resin, polyimide resin, polyester resin, epoxy resin, phenol resin, silicone resin, fluororesin, polyvinylpyrrolidone resin, polyurethane. Resin, epoxy resin, cyanate resin, melamine resin, malein resin, vinyl acetate resin, polyacetal resin, cellulose resin, methyl methacrylate resin,
Organic materials such as tetrafluoroethylene resin and polyether sulfone resin are preferable. These resins may be used alone or in combination. When combining a plurality of layers, a laminated structure may be used, or the resin existing on the side surface of the color conversion layer and the underlying resin may be different. More specifically, the oxygen permeable substrate of FIG. 3 may be 30 and 24 as well as 30. Here, 24 may be a light-shielding layer or a transparent layer. When the oxygen permeable substrates are 30 and 24, the contact area between the color conversion layer and the oxygen permeable substrate generally exceeds 50% of the surface area of the color conversion layer, which is preferable.

An oxygen permeable substrate made of an inorganic material generally has low oxygen permeability and is not preferred. However, it is not limited as long as oxygen can be taken in from the outside air or oxygen can be retained in the substrate by making it porous. For example, a porous glass plate, a porous ceramic plate and the like can be mentioned, and specific materials include silicon oxide, aluminum oxide, titanium oxide, yttrium oxide, germanium oxide, zinc oxide, magnesium oxide, calcium oxide, Strontium oxide, barium oxide, lead oxide, sodium oxide, zirconia, sodium oxide, lithium oxide, boron oxide, silicon nitride, soda-lime glass, barium-strontium-containing glass, lead glass,
Aluminosilicate glass, borosilicate glass, barium borosilicate glass, etc. can be mentioned. Further, it is more preferable that the oxygen-permeable substrate is an oxygen-enriched film. Since the oxygen-enriched film can take in oxygen from the air in the atmosphere with good selectivity, it is possible to supply oxygen to the color conversion layer in a concentration higher than that in the atmosphere (20% to 30%). The oxygen / nitrogen separation coefficient of the oxygen-enriched film is preferably 2 or more,
For example, a composite of montmorillonite, which is a layered clay mineral, and a synthetic bilayer membrane having a fluorine chain can be mentioned.

[Embodiment 1] FIG. 1 is a schematic view showing an organic EL light emitting device according to an embodiment of the present invention. The organic EL light emitting device 100 is an upper extraction type that extracts light from the side opposite to the substrate. Organic EL light emitting device 100
Is a TFT embedded in the electric insulating film 4 on the supporting substrate 2.
6, interlayer insulating film 8, organic EL element 16, oxygen barrier layer 2
0, an oxygen supply layer 22, and a color conversion member 28.
The organic EL element 16 sandwiches the organic light emitting medium 12 between the lower electrode 10 and the upper electrode 14. The color conversion member 28 includes a color conversion layer 26, a light shielding layer 24, and a sealing substrate (not shown, above the color conversion layer in FIG. 1) that supports them. The TFT 6 and the organic EL element 16 are formed by the contact hole 18.
Are electrically connected. The arrow in the figure represents the direction of extracting light.

The organic EL element 1 is driven by the TFT 6
The blue light emitted from 6 reaches the color conversion member 28 through the oxygen blocking layer 20 and the oxygen supply layer 22. The color conversion layer 26 of the color conversion member 28 converts part of the blue light into green light and red light, and the color conversion member 28 emits three colors. At this time, the light shielding layer 24 prevents the three colors from being mixed.

Since oxygen is supplied from the oxygen supply layer 22 to the color conversion layer 26, deterioration of the color conversion layer can be prevented. Further, since the oxygen blocking layer 20 is between the oxygen supply layer 22 and the organic EL element 16, the oxygen can be prevented from migrating from the oxygen supply layer 22 to the organic EL element 16 and the deterioration can be prevented.

In this embodiment, the oxygen supply layer 22 is arranged on the lower side of the color conversion layer 26, but it may be arranged on the upper side (between the color conversion layer and the sealing substrate). Further, the oxygen supply layer 22 is arranged in contact with the color conversion layer 26, but another layer may intervene as long as it is permeable to oxygen.

[Embodiment 2] FIG. 2 is a schematic view showing an organic EL light emitting device according to another embodiment of the present invention. In this figure, the same reference numerals as those in FIG. 1 denote the same members, and the description thereof will be omitted. Organic EL light emitting device 20 of Embodiment 2
0 means that the oxygen supply layer 22 is juxtaposed with the color conversion layer 26,
The oxygen supply layer 22 is the same as the organic EL light emitting device 100 of the first embodiment except that the oxygen supply layer 22 is partially present in the portion where the light shielding layer is present or is included in the light shielding layer. Since oxygen is supplied from the oxygen supply layer 22 to the color conversion layer 26, deterioration of the color conversion layer can be prevented. Further, since the oxygen blocking layer 20 is between the oxygen supply layer 22 and the organic EL element 16, the oxygen can be prevented from migrating from the oxygen supply layer 22 to the organic EL element 16 and the deterioration can be prevented. Note that the oxygen supply layer 22 of this embodiment partially exists in the portion where the light shielding layer exists or is included in the light shielding layer, but separately from the light shielding layer, one side, both sides, the upper side of the color conversion layer 26, It may be juxtaposed on the lower side or the like.

[Embodiment 3] FIG. 3 is a schematic view showing an organic EL light emitting device according to still another embodiment of the present invention. In this figure, the same reference numerals as those in FIG. 1 denote the same members, and the description thereof will be omitted. Organic EL light emitting device 300
Is a substrate extraction type that extracts light from the substrate side. The organic EL light emitting device 300 includes a color conversion member 28, an oxygen barrier layer 20, an organic EL element 1 on an oxygen permeable substrate 30.
6 is provided. In this figure, TFTs and the like are omitted, or the case of passive driving is shown. The arrow in the figure represents the direction of extracting light. In this device, the oxygen permeable substrate 30 also serves as a supporting substrate. Since the color conversion layer 26 is supplied with oxygen from the outside through the oxygen permeable substrate 30,
It is possible to prevent deterioration of the color conversion layer. In addition, the oxygen barrier layer 20
However, since it is between the oxygen-permeable substrate 30 and the organic EL element 16, the oxygen that has permeated the oxygen-permeable substrate 30 does not migrate to the organic EL element 16 and deterioration can be prevented.

In this embodiment, the oxygen permeable substrate 30 is arranged in contact with the color conversion layer 26, but another layer may be interposed as long as it is permeable to oxygen. Further, instead of the oxygen permeable substrate 30, an oxygen supply layer may be provided between the color conversion layer 26 and the oxygen blocking layer 20 as in the first embodiment, or as in the second embodiment. May be provided in parallel with the color conversion layer 26. Further, also in the top-out type devices of Embodiments 1 and 2, an oxygen permeable substrate may be provided above the color conversion layer instead of the oxygen supply layer.

[0051]

EXAMPLE Example 1 (Embodiment 1 type) Preparation of color conversion substrate 102 mm × 133 mm × 1.1 mm supporting substrate (OA
2 glass: manufactured by Nippon Electric Glass Co., Ltd.), V259BK (manufactured by Nippon Steel Chemical Co., Ltd.) was spin-coated as a material for the black matrix (BM), and was exposed to ultraviolet light through a photomask having a grid pattern. % Aqueous sodium carbonate solution and baked at 200 ° C. to form a black matrix (film thickness 1.5 μm) pattern.
Next, as a material for the blue color filter, V259B
(Nippon Steel Chemical Co., Ltd.) is spin coated to form a rectangle (90μ
BM through a photomask such that 320 stripe patterns of m lines and 240 μm gap) can be obtained.
The substrate was exposed to ultraviolet light by aligning with, and developed with a 2% sodium carbonate aqueous solution, and then baked at 200 ° C. to form a pattern of a blue color filter (film thickness 1.5 μm). next,
As a material for the green color filter, V259G (manufactured by Nippon Steel Chemical Co., Ltd.) was spin-coated to form a rectangular (90 μm line, 240 μm gap) stripe pattern.
Through a photomask such that 0 pieces can be obtained, the BM is aligned and exposed to ultraviolet rays, developed with a 2% sodium carbonate aqueous solution, baked at 200 ° C., and next to the blue color filter, a green color filter (film thickness A pattern of 1.5 μm) was formed. Next, as the material of the red color filter,
V259R (manufactured by Nippon Steel Chemical Co., Ltd.) was spin-coated, and UV exposure was performed by aligning it with the BM through a photomask such that 320 rectangular patterns (90 μm lines, 240 μm gaps) were obtained, and 2% sodium carbonate. After development with an aqueous solution, baking was performed at 200 ° C. to form a pattern of a red color filter (film thickness 1.5 μm) between the blue color filter and the green color filter.

Next, as a material for the green color conversion layer, 0.04
An ink was prepared by dissolving coumarin 6 in an amount of mol / kg (relative to solid content) in an acrylic negative photoresist (V259PA, solid content concentration 50%: Nippon Steel Chemical Co., Ltd.). This ink was spin-coated on the above substrate, and the portion corresponding to the green color filter was exposed to ultraviolet light, and
% Aqueous sodium carbonate solution and baked at 200 ° C. to form a green conversion film pattern (film thickness 10 μm) on the green color filter. Next, as materials for the red color conversion layer, coumarin 6: 0.53 g, basic violet 11: 1.5 g, rhodamine 6G: 1.5 g, acrylic negative photoresist (V259PA, solid content concentration 50).
%: Nippon Steel Chemical Co., Ltd.): An ink dissolved in 100 g was prepared. This ink was spin-coated on the above substrate, the portion corresponding to the red color filter was exposed to ultraviolet light, developed with a 2% sodium carbonate aqueous solution, and baked at 180 ° C. to form a red conversion film on the red color filter. Pattern (film thickness 10 μm) was formed to obtain a color conversion substrate (color conversion member).

(2) Fabrication of TFT Substrate FIGS. 4 (a) to 4 (i) are views showing a process of forming a polysilicon TFT. First, 112 mm × 143 mm × 1.
On a 1 mm glass substrate 2 (OA2 glass, manufactured by Nippon Electric Glass Co., Ltd.), low pressure chemical vapor deposition (Low Pressure Chemical
Vapor Deposition, LPCVD)
The Si layer 40 was laminated (FIG. 4A). Next, KrF
An excimer laser such as a (248 nm) laser is used as α-Si.
The layer 40 was irradiated and annealed and crystallized to form polysilicon (FIG. 4B). This polysilicon was patterned into islands by photolithography (FIG. 4 (c)). Obtained islanded polysilicon 4
1 and the surface of the substrate 2 are laminated with an insulating gate material 42 by chemical vapor deposition (CVD) or the like to form a gate oxide insulating layer 42.
(FIG. 4 (d)). Next, the gate electrode 43 is formed by vapor deposition or sputtering (FIG. 4E),
The gate electrode 43 was patterned and anodized (FIGS. 4F to 4H). Further, a doping region is formed by ion doping (ion implantation), and thereby an active layer is formed to form a source 45 and a drain 47, and a polysilicon TFT is formed (FIG. 4).
(I)). At this time, the gate electrode 43 (and the scan electrode 50 in FIG. 5, the bottom electrode of the capacitor 57) is Al, TFT
The source 45 and the drain 47 are of n + type.

Next, after forming an interlayer insulating film (SiO ₂ ) with a film thickness of 500 nm on the obtained active layer by the CRCVD method, the signal electrode line 51, the common electrode line 52, the capacitor upper electrode (Al ) And connecting the source electrode and the common electrode of the second transistor (Tr2) 56,
The drain of the transistor (Tr1) 55 and the signal electrode were connected (FIGS. 5 and 6). The connection between each TFT and each electrode was appropriately made by opening the interlayer insulating film SiO ₂ by wet etching with hydrofluoric acid. Next, Cr and ITO
By sputtering, 2000 Å,
The film was formed at 1300Å. A positive type resist (HPR204: made by Fuji Film Arch) is spin-coated on this substrate, and is exposed to ultraviolet light through a photomask having a dot pattern of 90 μm × 320 μm, and is exposed to UV rays.
It was developed with a developing solution of H (tetramethylammonium hydroxide) and baked at 130 ° C. to obtain a resist pattern. Next, the exposed part of the ITO is etched with an ITO etchant made of 47% hydrobromic acid, and then cerium ammonium nitrate / perchloric acid aqueous solution (HC
E: manufactured by Nagase & Co.) was used to etch Cr. next,
A resist stripper containing ethanolamine as a main component (N
303: manufactured by Nagase & Co., Ltd.) to obtain a Cr / ITO pattern (lower electrode: anode). At this time, Tr256 and the lower electrode 10 were connected via the opening 59 (FIG. 6). Next, as a second interlayer insulating film, a negative resist (V259BK: manufactured by Nippon Steel Chemical Co., Ltd.) was spin-coated,
It was exposed to ultraviolet rays and developed with a developer of TMAH (tetramethylammonium hydroxide). Next, baking was performed at 180 ° C. to form an organic interlayer insulating film (not shown) that covers the edge of Cr / ITO (ITO openings are 70 μm × 200 μm).

(3) Preparation of Organic EL Light Emitting Device The substrate with an interlayer insulating film thus obtained was ultrasonically cleaned in pure water and isopropyl alcohol, dried by Air blow, and then UV cleaned. Next, the TFT substrate was moved to an organic vapor deposition device (manufactured by Nippon Vacuum Technology), and the substrate was fixed to a substrate holder. It should be noted that the heating boats made of molybdenum were previously charged with 4,4 ′,
4 ″ -tris [N- (3-methylphenyl) -N-phenylamino] triphenylamine (MTDATA),
4,4′-bis [N- (1-naphthyl) -N-phenylamino] biphenyl (NPD), 4,4′-bis (2,2-diphenylvinyl) biphenyl (DPVBi) as a host of the light emitting material, 1,4-bis [4- (N, N-diphenylaminostyrylbenzene)] (DPAVB) as a dopant, an electron injection material and a cathode,
Tris (8-quinolinol) aluminum (Alq) and Li were charged respectively, and an IZO (previously described) target was attached to another sputtering tank as a cathode take-out electrode.

After that, the vacuum chamber was evacuated to 5 × 10 ⁻⁷ torr, and the layers from the hole injecting layer to the cathode were successively laminated in one vacuum without breaking the vacuum in the following order.
First, as the hole injecting layer, MTDATA has a vapor deposition rate of 0.1 to 0.3 nm / sec and a film thickness of 60 nm, and NPD has a vapor deposition rate of 0.1 to 0.3 nm / sec and a film thickness of 20 nm. , DPVBi and DPAVB have a vapor deposition rate of 0.1 to 0.3 nm / sec and a vapor deposition rate of 0.03 to 0.05 nm.
/ Second is co-evaporated to a film thickness of 50 nm, and the electron injection layer is
Alq vapor deposition rate 0.1-0.3 nm / sec, film thickness 20n
m, and as a cathode, Alq and Li were co-evaporated at vapor deposition rates of 0.1 to 0.3 nm / sec and 0.005 nm / sec, respectively, to a thickness of 20 nm. Next, the substrate was moved to a sputtering tank and IZO was used as a cathode take-out electrode.
An organic EL device was produced at a film forming rate of 0.1 to 0.3 nm / sec and a film thickness of 200 nm.

Next, as an oxygen blocking layer, SiOxNy (O / O +) was formed as a transparent inorganic film on the upper electrode of the organic EL element.
N = 50%: Atomic ratio) low temperature CVD
To form a film having a thickness of 200 nm (note that IZO also functions as an oxygen barrier layer). Oxygen permeation rate is 0.1 cc / m
It was less than ² · day. Next, the pixels were aligned with the color conversion substrate prepared above to cover the display portion, and the periphery of the display portion was photo-cured with a cation-curing adhesive (TB3102: manufactured by ThreeBond) to be bonded. Next, between this TFT substrate and the color conversion substrate, a fluorinated hydrocarbon bubbling oxygen (Fluorinert FC72: manufactured by Sumitomo 3M Limited, the amount of dissolved oxygen is 65 ml / 10 at 25 ° C. and atmospheric pressure).
0 ml) was injected from the gap portion of the bonding and the gap portion was sealed to form an oxygen supply layer. The thickness is about 10 μm.

(4) Evaluation of Organic EL Light Emitting Device In this way, the active organic EL display device (FIG. 1)
Was prepared, and a voltage of DC7V was applied to the lower electrode (ITO / Cr) and the extraction electrode (upper electrode) (IZO) of the cathode (lower electrode: (+), upper electrode: (−)),
The intersection (pixel) of each electrode emitted light. The emission luminance was 17 cd / m ² in the blue color filter section (blue pixel) with a colorimeter (CS100, made by Minolta), and the CIE chromaticity coordinates were X = 0.15 and Y = 0.16 for blue. 47 cd in emission, green conversion layer / green color filter (green pixel)
/ M ² CIE chromaticity coordinates, X = 0.27, Y = 0.67
Green emission, red conversion layer / red color filter section (red pixel) at 16 cd / m ² , CIE chromaticity coordinate is X =
A red emission of 0.64 and Y = 0.35 was obtained, and the three primary colors of light were obtained. In addition, the emission luminance of the organic EL element at that time is 200 cd / m ² (corresponding to all pixel emission, corresponding to 1/3 thereof for each color pixel), and the CIE chromaticity coordinate is X = 0.
The emission of blue light was 17 and Y = 0.28.

Next, under these driving conditions, room temperature is 22 ° C. for 10 minutes.
When driven for 00 hours, the blue pixel is 12 cd / m ²
(0.71 when the initial value is 1), the green pixel is 33 cd / m
² (0.70 when set to initial 1), red pixel is 11 cd /
m ² (0.69 when the initial value is 1), and the luminance of the organic EL element is 140 cd / m ² (0.70 when the initial value is 1)
Met. Further, the deterioration of the luminance of the organic EL element when the organic EL element was sealed with a normal inert gas such as dry nitrogen was 0.73 when the initial driving condition was 1. From this, it was found that there was almost no decrease in efficiency of the color conversion layer (Table 1), and even if the oxygen supply layer was arranged, the oxygen blocking layer was arranged, so there was almost no effect on the organic EL element.

Example 2 (Embodiment 1) In Example 1, as the oxygen supply layer, oxygen-excess dry air (dew point −50 ° C., oxygen 40%, nitrogen 60%) was used. Except that the TFT substrate and the color conversion substrate were attached in the circulated glove box)
Similarly, an organic EL light emitting device (FIG. 1) was produced. DC7V for the lower electrode (ITO / Cr) and upper electrode (IZO)
Voltage (lower electrode: (+), upper electrode: (-))
Then, the intersection (pixel) of each electrode emitted light. The emission brightness is 15 cd / m in a blue color filter (blue pixel) with a colorimeter (CS100, manufactured by Minolta).
² , CIE chromaticity coordinates are X = 0.15, Y = 0.16, blue emission, 42 cd / m ² in the green conversion layer / green color filter section (green pixel), CIE chromaticity coordinates are X = 0.2
7. Green emission of Y = 0.67, CIE chromaticity coordinates of 14 cd / m ² in the red conversion layer / red color filter section (red pixel), X = 0.64, Y = 0.35 of red Luminescence was obtained and the three primary colors of light were obtained. In addition, the emission luminance of the organic EL element at that time is 200 cd / m ² and the CIE chromaticity coordinate is
The emission was blue at X = 0.17 and Y = 0.28.

Next, under these driving conditions, room temperature is 22 ° C. for 10 minutes.
When driven for 00 hours, the blue pixel is 11 cd / m ²
(0.73 when set to initial 1), green pixel is 29 cd / m
² (0.69 when initial 1), red pixel is 10 cd /
m ² (0.71 when the initial value is 1), and the luminance of the organic EL element is 144 cd / m ² (0.72 when the initial value is 1).
Met. Further, the deterioration of the luminance of the organic EL element when the organic EL element was sealed with a normal inert gas such as dry nitrogen was 0.73 when the initial driving condition was 1. From this, it was found that there was almost no decrease in efficiency of the color conversion layer (Table 1), and even if the oxygen supply layer was arranged, the oxygen blocking layer was arranged, so there was almost no effect on the organic EL element.

Example 3 (Embodiment 3) An oxygen-permeable substrate (polyethersulfone resin: Sumitomo Bakelite: oxygen transmission rate 457 cc / m ² · day) was used as a 112 mm × 143 mm × 0.1 mm supporting substrate. A color conversion substrate was prepared in the same manner as in Example 1. still,
At this time, P / H was 45.7. Next, an acrylic thermosetting resin (V259PH: manufactured by Nippon Steel Chemical Co., Ltd.) was spin-coated on the above substrate as a flattening film and baked at 180 ° C. to form a flattening film (film thickness 5 μm). next,
As an oxygen barrier layer, SiOxNy (O
/ O + N = 50%: Atomic ratio) was formed into a film with a thickness of 200 nm by low temperature CVD. The amount of oxygen permeation was less than 0.1 cc / m ² · day.

Next, IZO (indium zinc oxide) was formed into a film with a thickness of 200 nm by sputtering. Next, a positive type resist (HPR204: manufactured by Fuji Film Arch) is spin-coated on this substrate, and a color conversion layer or a color filter pattern is formed through a photomask having a stripe pattern of 90 μm lines and 20 μm gaps. Was exposed to ultraviolet rays, developed with a developer of TMAH (tetramethylammonium hydroxide), and baked at 130 ° C. to obtain a resist pattern. Next, IZ composed of a 5% oxalic acid aqueous solution
The exposed portion of IZO was etched with an O etchant. Next, the resist is treated with a stripping solution (N303: Nagase & Co., Ltd.) containing ethanolamine as a main component,
IZO pattern (lower electrode: anode, number of lines 960)
Got

Next, as a first interlayer insulating film, a negative resist (V259PA: Nippon Steel Chemical Co., Ltd.) was spin-coated, exposed to ultraviolet light through a photomask, and TMAH.
It was developed with a developing solution of (tetramethylammonium hydroxide). Next, it was baked at 180 ° C. to cover the edges of the IZO pattern (the opening of IZO was 70 μm × 2).
90 μm) An interlayer insulating film was formed. Next, as a second interlayer insulating film (partition wall), a negative resist (ZPN110
0: manufactured by Zeon Corporation) was spin-coated and exposed to ultraviolet rays through a photomask having a stripe pattern of 20 μm lines and a gap of 310 μm, followed by post-exposure bake. Next, the negative resist was developed with a developer of TMAH (tetramethylammonium hydroxide) to form a second interlayer insulating film (partition wall) of an organic film orthogonal to the IZO stripe.

The substrate thus obtained was ultrasonically cleaned in pure water and isopropyl alcohol, dried by Air blow, and then UV-cleaned. The substrate was moved to an organic vapor deposition device (manufactured by Nippon Vacuum Technology) and fixed on a substrate holder. still,
In advance, 4,4 ′, 4 ″ -tris [N- (3-
Methylphenyl) -N-phenylamino] triphenylamine (MTDATA), 4,4′-bis [N- (1-
Naphthyl) -N-phenylamino] biphenyl (NP
D), 4,4'-bis (2,4) as a host of the light emitting material
2-diphenylvinyl) biphenyl (DPVBi), 1,4-bis [4- (N, N-diphenylaminostyrylbenzene)] (DPAVB) as a dopant, and tris (8-quinolinol) aluminum (Alq) as an electron injection material. ) And Li, and also Al as a cathode.

Then, the vacuum chamber was evacuated to 5 × 10 ⁻⁷ torr, and the layers from the hole injecting layer to the cathode were sequentially laminated by one evacuation without breaking the vacuum in the following order.
First, as the hole injecting layer, MTDATA has a vapor deposition rate of 0.1 to 0.3 nm / sec and a film thickness of 60 nm, and NPD has a vapor deposition rate of 0.1 to 0.3 nm / sec and a film thickness of 20 nm. , DPVBi and DPAVB have a vapor deposition rate of 0.1 to 0.3 nm / sec and a vapor deposition rate of 0.03 to 0.05 nm.
/ Second is co-evaporated to a film thickness of 50 nm, and the electron injection layer is
Alq vapor deposition rate 0.1-0.3 nm / sec, film thickness 20n
m, Alq, and Li are vapor deposition rates of 0.1 to 0.3 nm, respectively.
/ Sec, 0.005 nm / sec.
m, Al as a cathode, vapor deposition rate of 0.1 to 0.3 nm / sec,
An organic EL device was manufactured with a film thickness of 150 nm.

Next, this substrate was dried nitrogen (dew point -50).
Moved into the glove box that circulated (° C), 102m
The display part is covered with a blue sheet glass of m × 133 mm × 1.1 mm, and the periphery of the display part is a cationic hardening adhesive (TB.
3102: manufactured by ThreeBond Co., Ltd.) and light-cured to bond them to each other to manufacture a passive organic EL display device (FIG. 3).
The lower electrode (IZO) and the upper electrode (Al) are
At y = 1/120, a voltage of 15V is applied (lower electrode:
(+), Upper electrode: (-) When, the intersection (pixel) of each electrode emitted light. The emission brightness is measured by a color difference meter (C
S100, manufactured by Minolta), the CIE chromaticity coordinate is X at 16 cd / m ² in the blue color filter section (blue pixel).
= 0.15, Y = 0.16 blue emission, C at 45 cd / m ² in the green conversion layer / green color filter section (green pixel)
The IE chromaticity coordinates are X = 0.27, Y = 0.67, green emission, and 15 cd / m ² in the red conversion layer / red color filter section (red pixel), and the CIE chromaticity coordinates are X = 0. 64, Y
A red emission of 0.35 was obtained, and the three primary colors of light were obtained. In addition, the emission brightness of the organic EL element at that time is 200 cd.
/ M ² (corresponding to light emission of all pixels), the CIE chromaticity coordinate is X =
The emission was blue at 0.17 and Y = 0.28.

Next, under these driving conditions, room temperature is 22 ° C. for 10 minutes.
When driven for 00 hours, the blue pixel is 10 cd / m ²
(0.67 when set to initial 1), green pixel is 27 cd / m
² (0.60 when initial 1), red pixel is 9 cd / m
² (0.60 when the initial value was 1), and the luminance of the organic EL element was 126 cd / m ² (0.63 when the initial value was 1). In addition, the deterioration of the luminance of the organic EL element when the organic EL element was sealed with an inert gas such as normal dry nitrogen was 0.65 when the driving condition was 1 at the initial stage. From this, it was found that the efficiency of the color conversion layer was hardly reduced (Table 1), and the oxygen supply layer and the oxygen barrier layer were arranged, so that the organic EL element was hardly affected.

Comparative Example 1 (No Oxygen Supply Layer) In Example 1, a vacuum degassed fluorohydrocarbon (Fluorinert FC72, manufactured by Sumitomo 3M Limited, oxygen dissolution amount was <1 ml / at 25 ° C. and atmospheric pressure). (100 ml) was injected from the bonded gap portion, and the gap portion was sealed to form an oxygen supply layer, and an organic EL light emitting device was similarly prepared. A voltage of DC7V is applied to the lower electrode (ITO / Cr) and the upper electrode (IZO) (lower electrode:
(+), Upper electrode: (-) When, the intersection (pixel) of each electrode emitted light. The initial emission brightness is as in Example 1.
Was similar to. That is, in the color difference meter (CS100, made by Minolta), the blue color filter section (blue pixel) is set to 1
CIE chromaticity coordinates at 7 cd / m ² are X = 0.15, Y =
0.16 blue emission, green conversion layer / green color filter (green pixel) 47 cd / m ² CIE chromaticity coordinates, X = 0.27, Y = 0.67 green emission, red conversion Layer / red color filter section (red pixel) 16 cd / m
^{In 2} , CIE chromaticity coordinates were X = 0.64, Y = 0.35, and red light emission was obtained, and the three primary colors of light were obtained. At that time, the light emission luminance of the organic EL element was 200 cd / m ² (corresponding to light emission of all pixels), and the CIE chromaticity coordinates were X = 0.17, Y =
It had a blue emission of 0.28.

Next, under these driving conditions, room temperature is 22 ° C. for 10 minutes.
When driven for 00 hours, the blue pixel is 12 cd / m ²
(0.71 when the initial value is 1), the green pixel is 28 cd / m
² (0.60 when initial 1), red pixel is 5 cd / m
² (0.31 when the initial value was 1), and the luminance of the organic EL element was 140 cd / m ² (0.70 when the initial value was 1). Further, the deterioration of the luminance of the organic EL element when the organic EL element was sealed with a normal inert gas such as dry nitrogen was 0.73 when the initial driving condition was 1. As a result, a decrease in efficiency of the green and red conversion layers was recognized (Table 1), and the deterioration of the red conversion layer was particularly remarkable. It is considered that this is because the color conversion layer deteriorated because the oxygen supply layer was not arranged.

Comparative Example 2 (without oxygen permeable substrate) In Example 3, instead of the oxygen permeable substrate, a glass substrate (OA2 glass, manufactured by Nippon Electric Glass Co., Ltd.): Oxygen permeation amount: <0.1 cc / m ^An organic EL light emitting device was produced in the same manner except that ² · day) was used. At this time, P / H
<0.01. A voltage of 15 V was applied to the lower electrode (IZO) and the upper electrode (Al) at Duty = 1/120 (lower electrode: (+), upper electrode: (−)), and the intersection of each electrode (Pixel) emitted light. The initial emission brightness was similar to that of Example 3. That is, a CIE chromaticity coordinate is 16 cd / m ² in a blue color filter section (blue pixel) with a colorimeter (CS100, manufactured by Minolta), and blue light emission of X = 0.15 and Y = 0.16, 45 cd / m in green conversion layer / green color filter section (green pixel)
² , the CIE chromaticity coordinate is X = 0.27, Y = 0.67, green emission, and the red conversion layer / red color filter unit (red pixel) is 15 cd / m ² , the CIE chromaticity coordinate is X = 0.6
4, red emission of Y = 0.35 was obtained, and the three primary colors of light were obtained. The emission brightness of the organic EL element at that time is 20.
At 0 cd / m ² (corresponding to light emission from all pixels), CIE chromaticity coordinates were blue light emission with X = 0.17 and Y = 0.28.

Next, under these driving conditions, the temperature is 10 ° C. at room temperature of 22 ° C.
When driven for 00 hours, the blue pixel is 10 cd / m ²
(0.67 when set to initial 1), green pixel is 24 cd / m
² (0.53 when initial 1), red pixel is 5 cd / m
² (0.33 when the initial value was 1), and the luminance of the organic EL element was 126 cd / m ² (0.63 when the initial value was 1). In addition, the deterioration of the luminance of the organic EL element when the organic EL element was sealed with an inert gas such as normal dry nitrogen was 0.65 when the driving condition was 1 at the initial stage. As a result, a decrease in efficiency of the green and red conversion layers was recognized (Table 1), and the deterioration of the red conversion layer was particularly remarkable. It is considered that this is because the color conversion layer was deteriorated because the oxygen permeable substrate was not arranged.

Table 1 summarizes the changes in color conversion efficiency.

[Table 1]

[0074]

According to the present invention, it is possible to provide an organic EL light emitting device capable of suppressing deterioration of the color conversion layer.

[Brief description of drawings]

FIG. 1 is a schematic view showing an organic EL light emitting device according to an embodiment of the present invention.

FIG. 2 is a schematic view showing an organic EL light emitting device according to another embodiment of the present invention.

FIG. 3 is a schematic view showing an organic EL light emitting device according to still another embodiment of the present invention.

FIG. 4 is a diagram showing a process of forming a polysilicon TFT.

FIG. 5 is a circuit diagram showing an electric switch connection structure including a polysilicon TFT.

FIG. 6 is a plan perspective view showing an electric switch connection structure including a polysilicon TFT.

[Explanation of symbols]

100,200,300 Organic EL light emitting device 16 Organic EL device 20 oxygen barrier 22 Oxygen supply layer 26 color conversion layers 30 oxygen permeable substrate

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Hosokawa Gideo             1280 Kamizumi, Sodegaura, Chiba Prefecture F-term (reference) 3K007 AB03 AB04 AB12 BB06 DB03                       FA02

Claims (10)

[Claims] 1. An organic electroluminescence device, an organic electroluminescence device, a color conversion layer for converting light emitted from the organic electroluminescence device into light of different wavelengths, and an oxygen supply layer for supplying oxygen to the color conversion layer. Electroluminescent light emitting device. 2. The organic EL light emitting device according to claim 1, further comprising an oxygen blocking layer between the oxygen supply layer and the organic electroluminescence element. 3. The organic electroluminescence light emitting device according to claim 1, wherein the oxygen supply layer and the color conversion layer are laminated. 4. The organic electroluminescence light-emitting device according to claim 1, wherein the oxygen supply layer and the color conversion layer are arranged side by side. 5. An organic electroluminescence device, a color conversion layer for converting light emitted from the organic electroluminescence device into light of different wavelengths, and an oxygen-permeable substrate for transmitting oxygen from the outside to the color conversion layer. Organic electroluminescence light emitting device. 6. The film thickness of the color conversion layer is H (μm), and the oxygen permeation amount of the oxygen permeable substrate is P (cc / m ² · da).
The organic electroluminescent light emitting device according to claim 5, wherein P / H> 0.03 when y). 7. The surface area of the color conversion layer is 50% or more,
The organic electroluminescence light-emitting device according to claim 5, which is in contact with the oxygen-permeable substrate. 8. The organic electroluminescent light emitting device according to claim 5, further comprising an oxygen blocking layer between the oxygen permeable substrate and the organic electroluminescent element. 9. The organic electroluminescent light emitting device according to claim 5, wherein the oxygen permeable substrate is optically transparent. 10. The organic electroluminescence light emitting device according to claim 5, wherein the oxygen permeable substrate is made of porous glass.