KR101637171B1 - Organic light emitting device - Google Patents

Abstract

The present application is directed to organic light emitting devices and illumination. In the present application, it is possible to provide an active layer of an organic light emitting device, for example, a light emitting layer, or an element having excellent light emitting efficiency through interaction between light generated in the light emitting layer and a quantum dot.

Description

ORGANIC LIGHT EMITTING DEVICE

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an organic light emitting device and a use thereof.

BACKGROUND ART An organic light emitting diode (OLED) is an emissive element that generates light through the combination of electrons and holes by applying a voltage to a film of a fluorescent and / or phosphorescent organic compound.

Typically, the organic light emitting device sequentially includes a base layer, a first electrode layer, an organic layer including a light emitting layer, and a second electrode layer. The organic layer may include at least one functional layer selected from a hole injecting layer, a hole transporting layer, an electron transporting layer, a hole blocking layer, and an electron injecting layer in addition to the light emitting layer, if necessary.

In a structure referred to as a so-called bottom emitting device, the first electrode layer may be formed of a transparent electrode layer, and the second electrode layer may be formed of a reflective electrode layer. Also, in the structure referred to as a top emitting device, the first electrode layer may be formed as a reflective electrode layer, and the second electrode layer may be formed as a transparent electrode layer.

Electrons and holes are injected by the two electrode layers, respectively, and recombined in the light emitting layer to generate light. Light can be emitted toward the base layer side in the bottom emission type device and toward the second electrode layer side in the top emission type device.

Indium Tin Oxide (ITO), which is generally used as a transparent electrode layer in the structure of an organic light emitting device, and the base layer, which is an organic layer and usually a glass base layer, are approximately 2.0, 1.8 and 1.5, respectively. Due to the relationship of the refractive indexes, for example, light generated in the organic light emitting layer in the bottom emission type device is trapped by the total internal reflection phenomenon or the like in the interface between the organic layer and the first electrode layer or in the base layer , Only a very small amount of light is emitted.

The present application provides an organic light emitting device and its use.

The organic light emitting device of the present application includes a base layer, and sequentially includes a quantum dot, a first electrode layer, an organic layer, and a second electrode layer formed on the base layer. 1 shows a structure of an exemplary organic light emitting device in which a base layer 101, a quantum dot 102, a first electrode layer 103, an organic layer 104, and a second electrode layer 105 are sequentially formed. The organic light emitting device may be such that light generated in the organic layer is extracted toward the substrate layer through interaction with quantum dots and the like. In this case, the base layer may be a light-transmitting base layer, the first electrode layer may be a transparent electrode layer, and the second electrode layer may be a reflective electrode layer.

According to the above structure, the quantum dot interacts with an electromagnetic wave generated in an active layer of the organic layer, for example, a light emitting layer, so that light extraction efficiency can be improved.

A quantum dot is a semiconductor structure in which a material having a narrow band gap among two materials having different band gaps is grown and manipulated so as to have a size of de Broglie wavelength in a wide material. The quantum dots thus formed have a band structure that restricts the movement of electrons and holes, which are two carriers in a semiconductor, and thus can have an energy structure such as a particle in a box in quantum mechanics. With the unique structure of the quantum dots, for example, the size of the quantum dots can be adjusted to control the characteristics thereof, and the light extraction efficiency in the structure of the organic light emitting device can be greatly improved.

For example, when the wavelength range of the light generated in the organic layer includes a range of 380 nm to 780 nm, the average particle size of the quantum dots is about 1 nm to 1,000 nm, 1 nm to 500 nm, 1 nm to 200 nm, 1 nm to 100 nm, 1 nm to 90 nm, 1 nm to 80 nm, 1 nm to 70 nm, 1 nm to 60 nm, 1 nm to 50 nm, 1 nm to 40 nm, 1 nm to 30 nm, To about 20 nm. Through this adjustment, the light generated in the organic layer can increase the interaction with the quantum dots and greatly improve the light extraction efficiency.

The quantum dot can be selected from various types known in the art without any particular limitation, taking into consideration the interaction between the light generated in the light emitting layer and the light emitting layer. As the quantum dots, for example, MgO, MgS,

MgSe, MgTe, CaO, CaS, CaSe, CaTe, SrO, SrSe, SrTe, BaO, BaS, BaSe, BaTE, ZnO, Cu2O, ZnS, ZnSe, ZnTe, CdO, CdS, CdSe, CdTe, HgO, HgS, _{HgSe, HgTe, Al 2 S 3} , Al 2 Se 3, Al 2 Te 3, Ga 2 O 3, Ga 2 S 3, Ga 2 Se 3, Ga 2 Te 3, In 2 O 3, In 2 S 3, In _{2 Se 3, In 2 Te 3} , GeO 2, SnO 2, SnS, SnSe, SnTe, PbO, PbO 2, PbS, PbSe, PbTe, AlN, AlP, AlAs, AlSb, GaN, GaP, GaAs, GaSb, InN, InP, InAs, InSb, BP, Si, or Ge, or a mixture of two or more of them. As the quantum dots, for example, a suitable kind may be selected and used from a group II-VI material, a group III-VI material or a group IV material or a mixture of such materials. CdSe / CdSn, CdTe / CdSe, CdSe / ZnTe, CdSe / ZnS, InP / ZnSe (CdSe / CdZnSe) may be used as the quantum dots. Ag / TiO ₂ , Ag / SiO ₂ , Au / Pb, InP / ZnS, InP / ZnTe, CdSe / ZnSe, InP / GaAs, InGaAs / GaAs, PbTe / PbS, CuInS2 / ZnS, Co / CdSe, Zn / ZnO, , Au / Pt or Ru / Pt, but is not limited thereto.

As such quantum dots, those obtained through the well-known routes in the art may be used, or those prepared by known methods may be used. Methods for producing quantum dots are variously known and include various methods such as etching, self assembling, laser heat treatment, a method using an electric field applied to an electrode on a two-dimensional electron gas structure, etc. .

As illustrated in FIG. 1, the quantum dot 102 may be present in the binder layer 106.

The binder layer can be formed using, for example, a material capable of forming a base layer or a material having a refractive index similar to that of the first electrode layer or a binder layer having a higher refractive index. For example, the binder layer may have a refractive index equivalent to that of the adjacent first electrode layer, for example. In one example, the binder layer may have a refractive index of about 1.8 to 3.5 or 2.2 to 3.0 for a wavelength of 550 nm, but is not limited thereto. The binder material may be, for example, a thermally or photocurable monomeric, oligomeric or macromolecular organic material such as a polyimide, a caldo resin having a fluorene ring, a urethane, an epoxide, a polyester or an acrylate series Or an inorganic or organic composite material such as silicon oxide, silicon nitride, silicon oxynitride or polysiloxane, or the like. The binder material may include polysiloxane, polyamic acid, or polyimide. The polysiloxane may be formed by polycondensation of, for example, a condensation silane compound or a siloxane oligomer, or the like, and a binder material based on a bond of silicon and oxygen (Si-O) may be formed through the polycondensation. It is also possible to control the condensation conditions or the like in the process of forming the binder material so that the polysiloxane is based only on the siloxane bond (Si-O), or a part of the condensed functional group such as an organic group such as an alkyl group or an alkoxy group remains.

As the polyamic acid or polyimide, for example, a polyamic acid or polyimide having a refractive index of about 1.5 or more, about 1.6 or more, about 1.65 or more, or about 1.7 or more for light having a wavelength of 633 nm can be used. Such high refractive index polyamic acid or polyimide can be produced, for example, by using a monomer into which a halogen atom other than fluorine, a sulfur atom or a phosphorus atom is introduced. For example, it is possible to use a polyamic acid capable of improving the dispersion stability of the particles by allowing a site capable of binding to the particles such as a carboxyl group. As the polyamic acid, for example, a compound containing a repeating unit represented by the following formula (1) can be used.

[Chemical Formula 1]

In the formula (1), n is a positive number.

The repeating unit may be optionally substituted by one or more substituents. Examples of the substituent include functional groups including a halogen atom other than fluorine, a halogen atom such as a phenyl group, a benzyl group, a naphthyl group or a thiophenyl group, a sulfur atom or a phosphorus atom.

The polyamic acid may be a homopolymer formed only from the repeating unit represented by the formula (1), or may be a block or a random copolymer including units other than the repeating unit represented by the formula (1). In the case of a copolymer, the kind and ratio of other repeating units can be appropriately selected within a range that does not impair the desired refractive index, heat resistance, and light transmittance, for example.

Specific examples of the repeating unit of the formula (1) include repeating units of the following formula (2).

(2)

In formula (2), n is a positive number.

The polyamic acid may have a weight average molecular weight of about 10,000 to about 100,000 or about 10,000 to about 50,000, for example, in terms of standard polystyrene measured by GPC (Gel Permeation Chromatograph). The polyamic acid having the repeating unit represented by the formula (1) has a light transmittance of not less than 80%, not less than 85%, or not less than 90% in the visible light region and is excellent in heat resistance.

The binder layer may have an average particle diameter of 1 nm to 100 nm, 10 nm to 90 nm, 20 nm to 80 nm, 30 nm to 70 nm, 30 nm to 60 nm, or 30 nm to 30 nm, for example, And may further include high-refraction particles of about 50 nm. As the high refractive index particles, for example, alumina, titanium oxide, zirconium oxide or the like can be exemplified.

In another example, the binder layer may be formed by using a compound such as an alkoxide or acylate of a metal such as zirconium, titanium or cerium in combination with a material having a polar group such as a carboxyl group or a hydroxyl group. The compound such as an alkoxide or an acylate may undergo a condensation reaction with the polar group and may incorporate the metal in the skeleton of the binder layer to realize a high refractive index. Examples of the alkoxide or acylate compound include titanium alkoxides such as tetra-n-butoxytitanium, tetraisopropoxytitanium, tetra-n-propoxytitanium or tetraethoxytitanium, titanium stearate and the like Titanium chelates, tetra-n-butoxyzirconium, tetra-n-propoxyzirconium, tetraisopropoxyzirconium or tetraethoxyzirconium, zirconium alkoxide such as zirconium tributoxystearate, Acylate, zirconium chelates, and the like. As the material having the polar group, a suitable kind of binder among the binders described in the item of the scattering layer may be selected and used.

The binder layer is preferably a sol-gel coating method in which a coating liquid is prepared by mixing a metal alkoxide such as titanium alkoxide or zirconium alkoxide and a solvent such as alcohol or water and mixing the quantum dots again, As shown in FIG.

The ratio of the quantum dots in the binder layer thus formed, the thickness of the binder layer, and the like are not particularly limited and may be appropriately selected in consideration of the degree of interaction with the light generated in the light emitting layer or the light emitting layer. For example, the binder layer may contain quantum dots of about 0.1% to 20% by weight. Further, the binder layer may have a thickness of, for example, about 200 nm to 1 mu m. However, the ratio of the quantum dots and the thickness of the binder layer can be changed as needed.

As the substrate layer used in the organic light emitting device, a suitable material can be used as needed without particular limitation. In one example, as the substrate layer, a substrate layer having a transmittance of 50%, 60%, 70%, 80% or 90% or more with respect to light of a light transmitting base material layer, for example, a visible light region, may be used. As the light-transmitting base layer, a glass substrate or a transparent polymer base layer can be exemplified. As the glass substrate, a substrate layer containing soda-lime glass, barium / strontium-containing glass, lead glass, aluminosilicate glass, borosilicate glass, barium borosilicate glass or quartz can be exemplified. As the polymer base layer, A substrate layer including polyimide (PI), polyethylene naphthalate (PEN), polycarbonate, acrylic resin, poly (ethylene terephthalate), PES (poly sulfide) But is not limited thereto. The substrate layer may have an appropriate thickness in consideration of, for example, light transmittance, mechanical strength, or weight. The thickness of a conventional substrate layer may be, for example, from about 0.1 mm to 10 mm, from about 0.3 mm to about 5 mm, or from about 0.5 mm to about 2 mm.

Any one of the first and second electrode layers included in the organic light emitting device may be a hole injecting electrode layer and the other may be an electron injecting electrode layer. In addition, the first and second electrode layers may all be transparent electrode layers, or one of them may be a transparent electrode layer and the other may be a reflective electrode layer. Suitably, at least the first electrode layer formed on the base layer may be a transparent electrode layer. Hereinafter, for convenience of explanation, in the device having the structure as shown in Fig. 1, the first electrode layer 103 formed on the base layer 101 is a first electrode layer which is a hole injecting electrode layer and a transparent electrode layer, Although it is assumed that the electrode layer 105 is an electron injecting electrode layer and a reflective electrode, the positions and characteristics of the first and second electrode layers in the element are not limited to the above examples.

The electrode layer that is substantially transparent and capable of injecting holes can be formed using, for example, a transparent material having a relatively high work function. For example, the hole-injecting electrode layer may comprise a metal, an alloy, an electrically conductive compound or a mixture of two or more thereof having a work function of about 4.0 eV or more. As such a material, metal such as gold, CuI, indium tin oxide (ITO), indium zinc oxide (IZO), zinc tin oxide (ZTO), zinc oxide doped with aluminum or indium, magnesium indium oxide, nickel tungsten oxide, An oxide material such as ZnO, SnO ₂ or In ₂ O ₃ , a metal nitrides such as gallium nitride, metal serenides such as zinc serenide, and metal sulfides such as zinc sulfide. The transparent positive hole injecting electrode layer can also be formed using a metal thin film of Au, Ag or Cu and a laminate of a transparent material of high refractive index such as ZnS, TiO ₂ or ITO.

The transparent hole injecting electrode layer may be formed by any means such as vapor deposition, sputtering, chemical vapor deposition or electrochemical means. In addition, the electrode layer formed according to need may be patterned through a process using known photolithography, shadow mask, or the like. The film thickness of the hole injecting electrode layer varies depending on the light transmittance, the surface resistance, and the like, but may be usually in the range of 500 nm or 10 nm to 200 nm.

The electron injecting electrode layer can be formed using, for example, a material having a relatively small work function. For example, the electron injecting electrode layer can be formed using a suitable material among the materials used for forming the above-described hole injecting electrode layer, but the present invention is not limited thereto. The electron injecting electrode layer can also be formed using, for example, a vapor deposition method or a sputtering method, and can be appropriately patterned when necessary. The electron injecting electrode layer may be formed to have an appropriate thickness as required.

The organic layer present between the electron and the hole injecting electrode layer includes one or more light emitting layers. The organic layer may include a plurality of light emitting layers of two or more layers. When the light emitting layer includes two or more light emitting layers, the two or more light emitting layers may be in contact with or separated from each other, and if necessary, may be formed by an intermediate electrode layer having charge generating characteristics, a charge generating layer (CGL) But the present invention is not limited thereto.

The light-emitting layer can be formed, for example, by using various fluorescent or phosphorescent organic materials known in the art. Examples of materials that can be used for the light emitting layer include tris (4-methyl-8-quinolinolate) aluminum (III) (Alg3), 4-MAlq3 (C ₂₆ H ₂₆ N ₂ O ₂ S), DSA-amine, TBSA, BTP, PAP-NPA, Spiro-FPA, Ph ₃ Si (PhTDAOXD), PPCP Cyclopenadiene derivatives such as 2,3,4,5-pentaphenyl-1,3-cyclopentadiene, DPVBi (4,4'-bis (2,2'-diphenylyinyl) -1,1'- biphenyl) , Distyrylbenzene or a derivative thereof, or DCJTB (4- (Dicyanomethylene) -2-tert-butyl-6- (1,1,7,7-tetramethyljulolidyl-9- NPAMLI; Or Firpic, m-Firpic, N- Firpic, bon 2 Ir (acac), (C 6) 2 Ir (acac), bt 2 Ir (acac), dp 2 Ir (acac), bzq 2 Ir (acac), bo _{2 Ir (acac), F 2} Ir (bpy), F 2 Ir (acac), op 2 Ir (acac), ppy 2 Ir (acac), tpy 2 Ir (acac), FIrppy (fac-tris [2- ( ( ₂ , 4'-difluorophenyl) pyridine-C'2, N] iridium (III) or Btp ₂ Ir (acac) C3 '-) iridium (acetylacetonate), and the like, but the present invention is not limited thereto. The light emitting layer may contain the above material as a host and may also include perylene, distyrylbiphenyl, DPT, quinacridone, rubrene, BTX, ABTX or DCJTB. And may have a host-dopant system including a dopant.

The light-emitting layer can be formed by suitably employing a kind that exhibits luminescence characteristics among electron-accepting organic compounds or electron-donating organic compounds described below.

The organic layer may be formed with various structures, including various other functional layers known in the art, as long as the layer includes a light emitting layer. Examples of the layer that can be included in the organic layer include an electron injecting layer, a hole blocking layer, an electron transporting layer, a hole transporting layer, and a hole injecting layer.

The electron injection layer or the electron transport layer can be formed using, for example, an electron accepting organic compound. As the electron-accepting organic compound in the above, any known compound can be used without any particular limitation. Examples of such organic compounds include polycyclic compounds or derivatives thereof such as p-terphenyl or quaterphenyl, naphthalene, tetracene, pyrene, coronene, ), Polycyclic hydrocarbon compounds or derivatives thereof such as chrysene, anthracene, diphenylanthracene, naphthacene or phenanthrene, phenanthroline, Heterocyclic compounds or derivatives thereof such as bathophenanthroline, phenanthridine, acridine, quinoline, quinoxaline, or phenazine may be exemplified. It is also possible to use at least one of fluoroceine, perylene, phthaloperylene, naphthaloperylene, perynone, phthaloferrinone, naphthoferrinone, diphenylbutadiene ( diphenylbutadiene, tetraphenylbutadiene, oxadiazole, aldazine, bisbenzoxazoline, bisstyryl, pyrazine, cyclopentadiene, and the like. Oxine, aminoquinoline, imine, diphenylethylene, vinyl anthracene, diaminocarbazole, pyrane, thiopyrane, polymethine, Quinacridone or rubrene or derivatives thereof, Japanese Patent Application Laid-Open No. 1988-295695, Japanese Patent Application Laid-Open No. 1996-22557, Japanese Patent Application Laid-Open No. 1996-81472, Japanese Patent Application Laid-Open No. 1993-009470 or Japanese Patent Application Laid- For example, tris (8-quinolinolato) aluminum, a metal chelated oxanoid compound, bis (8-quinolinolato) aluminum, Bis (benzo (f) -8-quinolinolato] zinc}, bis (2-methyl-8-quinolinolato) aluminum, Tris (8-quinolinolato) indium], tris (5-methyl-8-quinolinolato) aluminum, 8- quinolinolato lithium, tris (5- Quinolinolato) gallium, bis (5-chloro-8-quinolinolato) calcium and the like, metal complexes having at least one of 8-quinolinolato or a derivative thereof as an arbiter, Japanese Patent Laid- Oxadiazole compounds disclosed in Japanese Patent Application Laid-Open Nos. 1995-179394, 1995-278124, and 1995-228579, Stilbene derivatives, distyrylarylene derivatives, and the like disclosed in Japanese Patent Application Laid-Open (kokai) No. 1994-132080 Styryl derivatives disclosed in JP-A-1994-88072 and the like, diolefin derivatives disclosed in JP-A-1994-100857 and JP-A-1994-207170, and the like; Fluorescent brightening agents such as benzooxazole compounds, benzothiazole compounds or benzoimidazole compounds; Bis (4-methylstyryl) benzene, distyrylbenzene, 1,4-bis (2-methylstyryl) benzene, Bis (2-methylstyryl) benzene, 1,4-bis (3-ethylstyryl) benzene, Methylstyryl) -2-ethylbenzene, and the like; Bis (4-methylstyryl) pyrazine, 2,5-bis (4-methylstyryl) pyrazine, 2,5- Bis [2- (4-biphenyl) vinyl] pyrazine such as bis (4-methoxystyryl) pyrazine, 2,5-bis [2- Distyrylpyrazine compounds, 1,4-phenylenedimethylidene, 4,4'-phenylenedimethylidyne, 2,5-xylenedimethylidyne, 2,6-naphthylenedimethylidyne, 1,4-biphenylene dimethyl (9,10-anthracenediyldimethylidine) or 4,4 '- (2,2-di-t-butylphenylvinyl) biphenyl , Dimethylidine compounds such as 4,4 '- (2,2-diphenylvinyl) biphenyl and derivatives thereof, silane disclosed in Japanese Patent Application Laid-Open No. 1994-49079 or Japanese Patent Application Laid-Open No. 1994-293778 Silanamine derivatives, Japanese Patent Application Laid-Open No. 1994-279322 or Japanese Patent Laid-Open Publication No. 1994-279323 Oxadiazole derivatives disclosed in Japanese Patent Laid-Open Publication No. 1994-109264, Japanese Patent Laid-Open Publication No. 1994-206865 and the like, an anthracene compound disclosed in Japanese Patent Oxynate derivatives disclosed in JP-A-1994-145146 and the like, tetraphenylbutadiene compounds disclosed in JP-A-1992-96990 and the like, organic trifunctional compounds disclosed in JP-A-1991-296595, A coumarin derivative disclosed in JP-A-1990-191694, a perylene derivative disclosed in JP-A-1990-196885, a naphthalene derivative disclosed in JP-A-1990-255789, Phthaloperynone derivatives disclosed in JP-A No. 1990-289676 or JP-A No. 1990-88689 or a derivative of phthaloperynone derivatives disclosed in JP-A No. 1990-25029 Styrylamine derivatives disclosed in, for example, Japanese Patent Laid-open Publication No. 2 (1990) can also be used as electron-accepting organic compounds contained in the low refractive layer. In addition, the electron injection layer may be formed using a material such as LiF or CsF.

The hole blocking layer is a layer which can prevent the injected holes from entering the electron injecting electrode layer through the light emitting layer to improve the lifetime and efficiency of the device. If necessary, the hole blocking layer can be formed using a known material, As shown in FIG.

The hole injecting layer or the hole transporting layer may include, for example, an electron donating organic compound. Examples of the electron donating organic compound include N, N ', N'-tetraphenyl-4,4'-diaminophenyl, N, N'- N, N ', N'-tetra-p-tolyl-4,4'-diaminobiphenyl, Phenyl, N, N'-di (4-methoxyphenyl) -4,4'-diaminobiphenyl, N, N'- (N, N ', N'-tetraphenyl-4,4'-diaminodiphenyl ether, 4,4'-bis (diphenylamino) quadriphenyl] 4-N, N-diphenylaminostilbene, N-phenylcarbazole, 1,1-bis (4-methoxy- Bis (4-dimethylamino-2-methylphenyl) phenylmethanesulfonate, 1,1-bis (4-di- N, N, N-tri (p-tolyl) amine, 4- (di-p- tolylamino) -4 ' N ', N'-tetraphenyl-4,4'-diaminobis N-phenylcarbazole, 4,4'-bis [N- (1-naphthyl) -N-phenylamino] biphenyl, Phenylamino] biphenyl, 4,4'-bis [N- (3-acenaphthenyl) -N (2-naphthyl) Phenylamino] biphenyl, 1,5-bis [N- (1-naphthyl) -N-phenylamino] naphthalene, 4,4'- Bis [N- (2-phenanthryl) -biphenylphenylamino] biphenyl, 4,4'-bis [N- N-phenylamino] biphenyl, 4,4'-bis [N- (2-pyrenyl) - N-phenylamino] biphenyl, 4,4'-bis [N- (1-choronenyl) - N-phenylamino] biphenyl), 2,6-bis (di-p-tolylamino) naphthalene, 2,6-bis (1-naphthyl) amino] naphthalene, 2,6-bis [N- (1-naphthyl) Bis [N, N-di (2-naphthyl) amino] terphenyl, 4,4'-bis { Bis [N, N-di- (2-naphthyl) amino] fluorene or 4,4'-bis (N, N-di-p-tolylamino) terphenyl and bis (N-1-naphthyl) (N-2-naphthyl) amine and the like are exemplified. It is not.

The hole injecting layer or the hole transporting layer may be formed by dispersing the organic compound in the polymer, or by using a polymer derived from the organic compound. Furthermore, hole-transporting non-conjugated polymers such as π-conjugated polymers and poly (N-vinylcarbazole) such as polyparaphenylenevinylene and derivatives thereof, σ conjugated polymers of polysilane, and the like can also be used have.

The hole injection layer may be formed by using a metal phthalocyanine such as copper phthalocyanine, a nonmetal phthalocyanine, a carbon film and an electrically conductive polymer such as polyaniline, or by reacting the arylamine compound with an Lewis acid using the arylamine compound as an oxidizing agent You may.

The organic layer may be formed in various structures including the above layers. For example, the organic layer may be formed, for example, in a form in which a light emitting layer and an electron transporting layer are sequentially formed from a hole injecting electrode layer, a form in which a light emitting layer, an electron transporting layer and an electron injecting layer are formed, a mode in which a hole transporting layer, A mode in which a hole transporting layer, a hole transporting layer, a hole transporting layer, a light emitting layer, a hole blocking layer and an electron transporting layer are formed, a mode in which a hole injecting layer, a hole transporting layer, a light emitting layer, a hole blocking layer and an electron transporting layer are formed, A hole injecting layer, a hole transporting layer, a light emitting layer, an electron transporting layer, and an electron injecting layer, but the present invention is not limited thereto. As mentioned above, if necessary, the organic layer may have a structure including two or more light emitting layers.

The organic light emitting device may further include a flat layer formed on the upper portion of the quantum dot, for example, between the quantum dot and the first electrode layer when necessary.

Such a flat layer provides a surface on which an electrode layer can be formed, and can realize better light extraction efficiency through interaction with quantum dots and the like. For example, the flat layer may have a refractive index equivalent to that of the adjacent electrode layers, and may have a refractive index of, for example, about 1.8 to 3.5 or 2.2 to 3.0. Such a flat layer can be formed using, for example, a material capable of forming a binder layer having a high refractive index from among the above-described materials for the binder layer.

The flat layer, which may exist on the binder layer or the quantum dot including the quantum dot, may have a smaller projected area than the first electrode layer formed on the upper part. The binder layer or the flat layer may have a smaller projected area than the base layer. The term " projected area " in this specification refers to an area of projection of an object to be recognized when the organic light emitting element or the above-mentioned substrate layer is observed from above or below the normal direction of its surface, for example, Layer, a flat layer, or an electrode layer. Therefore, even if the surface area of the binder layer, the flat layer, or the like is formed in a concavo-convex shape or the like, the actual surface area is larger than that of the electrode layer, It is interpreted to have a smaller projected area than the electrode layer if it is smaller than the recognized area when observed.

The binder layer or the flat layer may exist in various forms as long as the projected area is smaller than the base layer and the projected area is smaller than the electrode layer. For example, the binder layer or the flat layer 201 may be formed only on the portion of the base layer 101 except for the rim of the base layer 101 as shown in Fig. 2, or may be formed on the rim of the base layer 101 as shown in Fig. 201 may remain in some remaining form.

Fig. 4 is a view showing, by way of example, a case where the binder layer or the flat layer 201 of Fig. 2 is observed from above. 4, the area A of the electrode layer 103, that is, the projected area A of the electrode layer 103, which is recognized when viewed from above, is smaller than the projected area A of the binder layer or the flat layer 201 located therebelow (B). The ratio (A / B) of the projected area A of the electrode layer 103 to the projected area B of the binder layer or the flat layer 201 is 1.04 or more, 1.06 or more, 1.08 or more, 1.1 or more Or 1.15 or more. If the projected area of the binder layer or the flat layer is smaller than the projected area of the electrode layer, it is possible to realize a structure in which the binder layer or the flat layer is not exposed to the outside as described later, Is not particularly limited. Considering a typical production environment, the upper limit of the ratio A / B may be, for example, about 2.0, about 1.5, about 1.4, about 1.3, or about 1.25. The electrode layer may be formed on the base layer on which the binder layer or the flat layer is not formed. The electrode layer may be formed in contact with the base layer, or may include additional elements between the base layer and the base layer. With this structure, a structure in which the binder layer or the flat layer is not exposed to the outside can be realized.

For example, as shown in FIG. 4, the electrode layer may be formed up to a region including regions deviating from all peripheral portions of the binder layer or the flat layer when observed from above. In this case, for example, when a plurality of binder layers or flat layers 201 are present on the base layer as shown in FIG. 3, at least one binder layer or flat layer among the binder layer or the flat layer 201, for example, , The electrode layer 103 may be formed at least on the region including the region where the organic layer exists in the binder layer or the entirety of the peripheral region of the flat layer. For example, if an organic layer is formed on the binder layer or the flat layer existing on the right and left edges of the structure of FIG. 3, the structure of FIG. 3 extends to the left and right sides, The structure may be changed so that the electrode layer is formed up to an area out of all peripheral regions of the binder layer or the flat layer. When a sealing structure described later is attached to an electrode layer having no binder layer or a flat layer formed therebelow in the above structure, a structure in which the binder layer or the flat layer is not exposed to the outside can be formed. As a result, it is possible to prevent the binder layer or the flat layer from becoming a route through which water, oxygen or the like penetrates from the outside, and to stably secure the sealing structure, the adhesion of the electrode layer and the base layer, or the attachment of the external power source and the electrode layer, It is possible to maintain the surface hardness of the outer portion of the honeycomb structured body at an excellent level.

The adjustment of the projected area can be carried out, for example, by forming an electrode layer with a projected area larger than that of the binder layer or the flat layer in the vapor deposition or sputtering process for forming the electrode layer. If necessary, The patterning may be performed by removing the portion.

The organic light emitting element may be present in an appropriate encapsulation structure for blocking external moisture or oxygen. That is, the organic light emitting diode may further include a sealing structure for protecting the second electrode layer and the organic layer. The sealing structure may be a can, such as a glass can or a metal can, or may be a film covering the entire surface of the organic layer.

5 shows a configuration in which a sealing structure 501 of a can structure such as a glass can or a metal can is additionally included as the sealing structure 501 for protecting the sequentially formed second electrode layer 105 and the organic layer 104, . As shown in Fig. 5, the sealing structure 501 may be attached to the electrode layer 103 by, for example, an adhesive. When the binder layer or the flat layer 201 is present, the sealing structure may be adhered to the electrode layer 103 where the binder layer or the flat layer 201 is not present, for example, at the bottom. For example, as shown in Fig. 5, the sealing structure 501 may be adhered to the electrode layer 103 existing on the terminal rim of the base layer 101 with an adhesive. In this way, the protection effect through the sealing structure can be maximized.

The sealing structure may be, for example, a film covering the entire surface of the organic layer and the second electrode layer. FIG. 6 exemplarily shows a film-like encapsulation structure 501 covering the entire surface of the organic layer 104 and the second electrode layer 105. For example, the film-shaped encapsulation structure 501 is formed by covering the entire surface of the organic layer 104 and the second electrode layer 105 as shown in Fig. 6, and forming the binder layer or the flat layer 201 and the first transparent electrode layer 103 And the upper second substrate 601 are bonded to each other. As the second substrate 601, for example, a glass substrate, a metal substrate, a polymer film, a barrier layer, or the like can be exemplified. The film-shaped encapsulation structure may be formed by applying a liquid material which is cured by irradiation with heat or ultraviolet (UV), such as epoxy resin, and curing it, or by using the epoxy resin or the like, And the upper substrate may be laminated using an adhesive sheet or the like.

The encapsulation structure may include, if necessary, a metal oxide such as calcium oxide or beryllium oxide, a moisture absorbent such as a metal halide such as calcium chloride or phosphorous pentoxide, or a getter material. The moisture adsorbent or getter material may be contained in, for example, a film-type sealing structure or may exist at a predetermined position of the sealing structure of the can structure. The encapsulation structure may further include a barrier film, a conductive film, and the like.

In the case where a binder layer or a flat layer exists in the organic light emitting element, for example, as shown in Fig. 5 or 6, the sealing structure may be a structure in which a binder layer or a flat layer 201, (Not shown). Accordingly, a sealing structure in which the binder layer or the flat layer is not exposed to the outside can be realized. The sealing structure may be, for example, a structure in which the entire surface of the binder layer or the flat layer is surrounded by the base layer, the electrode layer and / or the sealing structure, or the sealing structure formed by including the base layer, the electrode layer and / Which is enclosed by the insulating layer and is not exposed to the outside. The sealing structure may include the base layer, the electrode layer, and the sealing structure, and may also include other elements, for example, an electrode layer and / or an encapsulation structure, so long as the sealing layer is formed so as not to be exposed to the outside. For example, a conductive material or an intermediate layer may be formed. For example, in FIG. 5 or 6, another element may exist at a portion where the base layer 101 and the electrode layer 103 are in contact with each other or at a portion where the first electrode layer 103 and the sealing structure 501 are in contact with each other. Examples of the other elements include an organic material, an inorganic material, an organic-inorganic hybrid material, an insulating layer or an auxiliary electrode layer, and the like, which are low in moisture permeability.

The present application also relates to the use of such organic light emitting devices. The organic light emitting device may be a backlight of a liquid crystal display (LCD), a light source such as a lighting device, various sensors, a printer, a copying machine, a vehicle instrument light source, a traffic light, a display, A display, a decoration, or a variety of lights. In one example, the present application relates to a lighting device comprising the organic light-emitting device. In the case where the organic light emitting device is applied to the illumination device or other use, the other components constituting the device or the like and the constitution method of the device are not particularly limited. As long as the organic light emitting device is used, Any of the materials or methods may be employed.

In the present application, it is possible to provide an active layer of an organic light emitting device, for example, a light emitting layer, or an element having excellent light emitting efficiency through interaction between light generated in the light emitting layer and a quantum dot.

1 is a view showing an exemplary organic light emitting device.
FIGS. 2 to 4 are views showing only the substrate layer, the first electrode layer, the scattering layer, and the heat dissipation diffusion layer region in the organic light emitting device.
5 and 6 are views showing an exemplary organic light emitting device.

Hereinafter, the organic light emitting device will be described in detail with reference to examples and comparative examples, but the scope of the organic light emitting device is not limited by the following embodiments.

Example  One.

A sol-gel coating solution was prepared by dispersing about 1 g of a quantum dot (CdSe / CdZnS) (average particle diameter: about 4 nm to 7 nm) synthesized in 10 g of tetramethoxysilane in a well-known manner. Subsequently, the prepared coating solution was coated on a glass substrate, and the sol-gel reaction was allowed to proceed to form a binder layer in which quantum dots were dispersed therein. Thereafter, the formed layer was irradiated with a laser to remove a part of the binder layer so that the position of the remaining binder layer corresponded to the light emitting region of the organic layer to be subsequently formed. After the removal, a hole injecting electrode layer including ITO (Indium Tin Oxide) was formed on the entire surface of the glass substrate by a known sputtering method. Subsequently, a solution containing an alpha -NPD (N, N'-Di- [(1-naphthyl) -N, N'- diphenyl] -1,1'- biphenyl) -4,4'- (4,4 ', 4 "-tris (N-carbazolyl) -triphenylamine (TCTA): Firpic, TCTA: Fir6) were successively formed on the light- (Al) electrode layer as an electron injecting reflective electrode was formed on the electron transporting layer by a vacuum evaporation method to manufacture a device. The electron transporting layer was formed of 4 ', 4 "-tris (N-carbazolyl) -triphenylamine . Subsequently, an encapsulation structure was attached to the device in a glove box in an Ar gas atmosphere to manufacture an apparatus. Then, the device was taken out into the air to measure voltage-current characteristics, luminance and efficiency at a current density of 3 mAcm -2 in the integrating hemisphere. Meanwhile, the refractive index is a value measured at a wavelength of about 550 nm using an ellipsometer manufactured by Nanoview.

Comparative Example  One.

An organic light emitting device was prepared in the same manner as in Example 1, except that the binder layer was not formed.

The results of the performance evaluation of the above Examples and Comparative Examples are shown in Table 1 below. The evaluation of absolute quantum efficiency in the following Table 1 was carried out in a known manner.

The driving voltage (V) Absolute Quantum Efficiency (%) Example 1 2.7 48.1 Comparative Example 1 2.8 30.6

101: base layer 102: quantum dot
103: first electrode layer 104: organic layer
105: second electrode layer 106: binder layer
201: a binder layer or a flat layer
501: sealing structure 601: second substrate

Claims (12)

A base layer; Quantum dots present on the base layer; And a first electrode layer on the quantum dot; An organic layer formed on the first electrode layer and including a light emitting layer; And a second electrode layer, wherein a wavelength range of light generated in the organic layer is in a range of 380 nm to 780 nm, and the average particle size of the quantum dots is such that the quantum dots interact with electromagnetic waves generated in the organic layer, And a binder layer is present between the base layer and the first electrode layer, the quantum dots are contained in the binder layer, and the binder layer has a thickness of 550 nm A refractive index with respect to a wavelength is within a range of 1.8 to 3.5, and the binder layer contains 0.1 to 20 wt% of the quantum dot. delete The organic light-emitting device according to claim 1, wherein the quantum dot is formed of at least one material selected from the group consisting of a group II-VI material, a group III-VI material, and a group IV material. The organic light emitting device according to claim 1, wherein the quantum dot has a core / shell structure. The method of claim 4, wherein the quantum dots of the core / cell structure are selected from the group consisting of CdSe / CdZnS, CdTe / CdSe, CdSe / ZnTe, CdSe / ZnS, InP / ZnSe, InP / ZnS, InP / ZnTe, CdSe / ZnSe, InP / the organic light emitting device / GaAs, PbTe / PbS, CuInS2 / ZnS, Co / CdSe, Zn / ZnO, Ag / TiO 2, Ag / SiO 2, Au / Pb, Au / Pt or Ru / Pt. delete The organic light-emitting device according to claim 1, wherein the binder layer has a refractive index of 2.2 to 3.0 at a wavelength of 550 nm. The method according to claim 1, wherein the projected area of the binder layer is smaller than the projected area of the first electrode layer, and the first electrode layer is formed on both the upper portion of the binder layer and the upper portion of the base layer on which the binder layer is not formed Organic light emitting device. The organic light emitting device according to claim 8, further comprising a sealing structure for protecting the organic layer and the second electrode layer, wherein the sealing structure is attached to an upper portion of the first electrode layer on which a binder layer is not formed. The organic light emitting device according to claim 9, wherein the sealing structure is a glass can or a metal can. The organic light emitting diode according to claim 9, wherein the sealing structure is a film covering the entire surface of the organic layer and the second electrode layer. A lighting device comprising the organic light-emitting device of claim 1.

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